Edibility of sport fishes in the Ottawa River near Chalk River Laboratories

International Nuclear Information System (INIS)

Lee, D.R.; Chaput, T.; Miller, A.; Wills, C.A.

2013-01-01

To address the question of edibility of fish in the Ottawa River near Chalk River Laboratories (CRL), 123 game fish were collected for analysis from four locations: Mackey and Rolphton (45 km and 35 km upstream of Chalk River Laboratories (CRL), respectively), the Sandspit (Pointe au Bapteme) and Cotnam Island (1.6 km and 45 km downstream of CRL, respectively). Twenty-six to thirty-six game fish were collected at each location in 2007 and samples of flesh or bone were analyzed. Trap nets were used to collect only the fish required, allowing release of management-sensitive species. The focus was on walleye (Sander vitreus) because they are abundant and popular among anglers. A few northern pike (Esox lucius) and a smaller number of smallmouth bass (Micropterus dolomieui) were also collected at three of the four sites. Samples of the fish were analyzed for cesium-137 ( 137 Cs), strontium-90 ( 90 Sr), mercury (Hg), and selected organo-chlorine compounds. Concentrations of 137 Cs in the flesh and 90 Sr in the bones of sport fish were low and similar at all four locations and appear to reflect the global residuals from nuclear weapons testing (primarily in the 1960's) as opposed to releases from CRL. Possible explanations are: 1) Reductions in radionuclide releases from CRL in recent decades and 2) Relatively large foraging ranges of sport fish. Mercury concentrations were elevated in fishes in the Ottawa River and were significantly higher at the Sandspit and Rolphton than at Mackey and Cotnam Island (p<0.001). Mercury concentrations from the four sites are comparable to concentrations in other Ontario and Quebec lakes. It is advisable therefore, that consumers follow the fish consumption guidelines issued by provincial authorities when eating fish from the Ottawa River. Organo-chlorine compounds were not detected in walleye; however, they were detected in all eight of the pike collected at Cotnam Island. The highest organo-chlorine concentrations were measured in two

An overview of the waste characterization program at Chalk River Nuclear Laboratories

International Nuclear Information System (INIS)

Csullog, G.W.; Hardy, D.G.

1990-05-01

A comprehensive Waste Characterization Program (WCP) is in place at Chalk River Laboratories to support disposal projects. The WCP is responsible for: 1) specifying the manifests for waste shipments; 2) developing and maintaining central databases for waste inventories and analytical data; and 3) developing the technologies and procedures to characterize the radiological and the physical/chemical properties of wastes. WCP work is being performed under the umbrella of a newly developed waste management Quality Assurance (QA) program. This paper gives an overview of the WCP with an emphasis on the requirements for determining radionuclide inventories in wastes, for implementing record-keeping systems, and for maintaining a QA program for disposal operations

Radiocarbon dating with the Chalk River MP Tandem accelerator

International Nuclear Information System (INIS)

Ball, G.C.; Andrews, H.R.; Brown, R.M.; Burn, N.; Davies, W.G.; Imahori, Y.; Milton, J.C.D.

1981-01-01

During the past three years an automated radiocarbon dating system based on the MP Tandem accelerator has been developed for the analysis of 14 C in groundwater samples from the nuclear waste disposal research program and other small samples of scientific interest. At the present time 14 C/ 12 C ratio measurements can be determined with an accuracy of about 5% and the system background levels (approx. 35000 to 45000 years) are totally determined by sample and/or ion source contamination. Our goal has been to develop a dedicated reliable system for routine analysis that will produce accurate results with a minimum expenditure of human resources and accelerator beam time. Improvements required to operate the tandem accelerator as a quantitative tool have also benefited the rest of the experimental nuclear physics program. The early evolution of the dating facility was described previously. This paper is a brief report of the current status at Chalk River

Field burial results and SIMS analysis of the Chalk River glass blocks

International Nuclear Information System (INIS)

Tait, J.C.; Hocking, W.H.; Betteridge, J.S.; Bart, G.

1986-01-01

In 1959, 25 2-kg hemispherical blocks of aluminosilicate glass, each containing ∼90 MBq/g of mixed fission products, were buried in a sandy soil aquifer in the waste management area at the Chalk River Nuclear Laboratories. A second set of blocks, containing ∼260 MBq/g mixed fission products, was buried in 1960. One block from each test was retrieved in 1978 to undergo chemical and surface analysis. This report reviews the migration of the 90 Sr and 137 Cs plume in the soil and presents the results of SIMS depth profiling of the surface of a glass block. (author)

Initial field measurements on the Chalk River superconducting cyclotron

International Nuclear Information System (INIS)

Ormrod, J.H.; Chan, K.C.; Hill, J.H.

1980-12-01

The midplane magnetic field of the Chalk River superconducting cyclotron has been mapped in detail over the full operating range of 2.5 to 5 tesla. The field measuring apparatus is described and results given include measurements of the field stability, reproducibility and harmonic content. (author)

Isotope hydrology of the Chalk River Laboratories site, Ontario, Canada

Science.gov (United States)

Peterman, Zell; Neymark, Leonid; King-Sharp, K.J.; Gascoyne, Mel

2016-01-01

This paper presents results of hydrochemical and isotopic analyses of groundwater (fracture water) and porewater, and physical property and water content measurements of bedrock core at the Chalk River Laboratories (CRL) site in Ontario. Density and water contents were determined and water-loss porosity values were calculated for core samples. Average and standard deviations of density and water-loss porosity of 50 core samples from four boreholes are 2.73 ± 12 g/cc and 1.32 ± 1.24 percent. Respective median values are 2.68 and 0.83 indicating a positive skewness in the distributions. Groundwater samples from four deep boreholes were analyzed for strontium (87Sr/86Sr) and uranium (234U/238U) isotope ratios. Oxygen and hydrogen isotope analyses and selected solute concentrations determined by CRL are included for comparison. Groundwater from borehole CRG-1 in a zone between approximately +60 and −240 m elevation is relatively depleted in δ18O and δ2H perhaps reflecting a slug of water recharged during colder climatic conditions. Porewater was extracted from core samples by centrifugation and analyzed for major dissolved ions and for strontium and uranium isotopes. On average, the extracted water contains 15 times larger concentration of solutes than the groundwater. 234U/238U and correlation of 87Sr/86Sr with Rb/Sr values indicate that the porewater may be substantially older than the groundwater. Results of this study show that the Precambrian gneisses at Chalk River are similar in physical properties and hydrochemical aspects to crystalline rocks being considered for the construction of nuclear waste repositories in other regions.

Field test of wireless sensor network in the nuclear environment

International Nuclear Information System (INIS)

Li, L.; Wang, Q.; Bari, A.; Deng, C.; Chen, D.; Jiang, J.; Alexander, Q.; Sur, B.

2014-01-01

Wireless sensor networks (WSNs) are appealing options for the health monitoring of nuclear power plants due to their low cost and flexibility. Before they can be used in highly regulated nuclear environments, their reliability in the nuclear environment and compatibility with existing devices have to be assessed. In situ electromagnetic interference tests, wireless signal propagation tests, and nuclear radiation hardness tests conducted on candidate WSN systems at AECL Chalk River Labs are presented. The results are favourable to WSN in nuclear applications. (author)

Field test of wireless sensor network in the nuclear environment

Energy Technology Data Exchange (ETDEWEB)

Li, L., E-mail: lil@aecl.ca [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Wang, Q.; Bari, A. [Univ. of Western Ontario, London, Ontario (Canada); Deng, C.; Chen, D. [Univ. of Electronic Science and Technology of China, Chengdu, Sichuan (China); Jiang, J. [Univ. of Western Ontario, London, Ontario (Canada); Alexander, Q.; Sur, B. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

2014-06-15

Wireless sensor networks (WSNs) are appealing options for the health monitoring of nuclear power plants due to their low cost and flexibility. Before they can be used in highly regulated nuclear environments, their reliability in the nuclear environment and compatibility with existing devices have to be assessed. In situ electromagnetic interference tests, wireless signal propagation tests, and nuclear radiation hardness tests conducted on candidate WSN systems at AECL Chalk River Labs are presented. The results are favourable to WSN in nuclear applications. (author)

Mortality study of Canadian military personnel exposed to radiation: atomic test blasts and Chalk River nuclear reactor clean-ups, 1950's

International Nuclear Information System (INIS)

Raman, S.; Dulberg, C.S.; Spasoff, R.A.

1984-08-01

This report describes a historical cohort study of the group of Canadian military personnel exposed to radiation in the 1950s at atomic bomb test blasts in the U.S. and Australia, and at clean-up operations at the Chalk River Nuclear Laboratories. Overall and cause-specific mortality in the exposed group was compared to that of the control cohort of unexposed military personnel, matched on age, service, rank and trade. Analyses indicated no elevation in the exposed cohort, in overall or cause-specific mortality due to diseases associated with radiation. Since this study was restricted to an investigation of mortality, we must stress that we cannot generalize these results or conclusions to current morbidity experienced by the exposed cohort

Measurements with the Chalk River Calorimeters

International Nuclear Information System (INIS)

Boyd, A.W.

1970-01-01

The Chalk River calorimeters were designed to measure the absorbed dose rate in reactors in materials such as graphite, polyethylene and beryllium in the range 0.01-1 Wg -1 . To eliminate heaters in the sample they were made to operate adiabatically, or more accurately quasi-adiabatically since there is no heater on the jacket. Both the sample and jacket temperatures are recorded from the time of insertion in the reactor flux and the absorbed dose rate is calculated from these data. The advantages of this type of calorimeter are the ease of construction and the absence of a sample heater. The disadvantage is that dose rates below ~ 10 mWg -1 cannot be determined accurately

ACE - an algebraic compiler and encoder for the Chalk River datatron computer

International Nuclear Information System (INIS)

Kennedy, J.M.; Okazaki, E.A.; Millican, M.

1960-03-01

ACE is a program written for the Chalk River Datatron (Burroughs 205) Computer to enable the machine to compile a program for solving a problem from instructions supplied by the user in a notation related much more closely to algebra than to the machine's own code. (author)

WIMS-CRNL: A user's manual for the Chalk River version of WIMS

International Nuclear Information System (INIS)

Donnelly, J.V.

1986-01-01

This report describes the preparation of the input for WIMS-CRNL, the Chalk River version of the WIMS lattice code. Also included are notes on the operation of the code, contents of the associated libraries, and the relation of WIMS-CRNL to other versions of the code

The new Chalk River AMS ion source, sample changer and external sample magazine

International Nuclear Information System (INIS)

Koslowsky, V.T.; Bray, N.; Imahori, Y.; Andrews, H.R.; Davies, W.G.

1997-01-01

A new sample magazine, sample changer and ion source have been developed and are in routine use at Chalk River. The system features a readily accessible 40-sample magazine at ground potential that is external to the ion source and high-voltage cage. The samples are held in an inert atmosphere and can be individually examined or removed; they can be exchanged en masse as a complete magazine concurrent with an AMS measurement. On-line sample changing is done with a pneumatic rabbit transfer system employing two stages of differential pumping. At Chalk River this is routinely performed across a 200 kV potential. Sample positioning is precise, and hundreds of 36 Cl and 129 I samples have been measured over a period of several days without interruption or alteration of ion source operating conditions. (author)

Reactor loops at Chalk River

International Nuclear Information System (INIS)

Sochaski, R.O.

1962-07-01

This report describes broadly the nine in-reactor loops, and their components, located in and around the NRX and NRU reactors at Chalk River. First an introduction and general description is given of the loops and their function, supplemented with a table outlining some loop specifications and nine simplified flow sheets, one for each individual loop. The report then proceeds to classify each loop into two categories, the 'main loop circuit' and the 'auxiliary circuit', and descriptions are given of each circuit's components in turn. These components, in part, are comprised of the main loop pumps, the test section, loop heaters, loop coolers, delayed-neutron monitors, surge tank, Dowtherm coolers, loop piping. Here again photographs, drawings and tables are included to provide a clearer understanding of the descriptive literature and to include, in tables, some specifications of the more important components in each loop. (author)

Management of legacy spent nuclear fuel wastes at the Chalk River Laboratories: operating experience and progress towards waste remediation

International Nuclear Information System (INIS)

Cox, D.S.; Bainbridge, I.B.; Greenfield, K.R.

2006-01-01

AECL has been managing and storing a diversity of spent nuclear fuel, arising from operations at its Chalk River Laboratories (CRL) site over more than 50 years. A subset of about 22 tonnes of research reactor fuels, primarily metallic uranium, have been identified as a high priority for remediation, based on monitoring and inspection that has determined that these fuels and their storage containers are corroding. This paper describes the Fuel Packaging and Storage (FPS) project, which AECL has launched to retrieve these fuels from current storage, and to emplace them in a new above-ground dry storage system, as a prerequisite step to decommissioning some of the early-design waste storage structures at CRL. The retrieved fuels will be packaged in a new storage container, and subjected to a cold vacuum drying process that will remove moisture, and thereby reduce the extent of future corrosion and degradation. The FPS project will enable improved interim storage to be implemented for legacy fuels at CRL, until a decision is made on the ultimate disposition of legacy fuels in Canada. (author)

Use of borehole-geophysical logs and hydrologic tests to characterize crystalline rock for nuclear-waste storage, Whiteshell Nuclear Research Establishment, Manitoba, and Chalk River Nuclear Laboratory, Ontario, Canada

International Nuclear Information System (INIS)

Davison, C.C.

1982-12-01

A number of borehole methods were used in the investigation of crystalline rocks at Whiteshell Nuclear Research Establishment and Chalk River Nuclear Laboratory in Canada. The selection of a crystalline-rock mass for the storage of nuclear waste likely will require the drilling and testing of a number of deep investigative boreholes in the rock mass. Although coring of at least one hole in each new area is essential, methods for making in-situ geophysical and hydrologic measurements can substitute for widespread coring and result in significant savings in time and money. Borehole-geophysical logging techniques permit the lateral extrapolation of data from a core hole. Log response is related to rock type, alteration, and the location and character of fractures. The geophysical logs that particularly are useful for these purposes are the acoustic televiewer and acoustic waveform, neutron and gamma, resistivity, temperature, and caliper. The acoustic-televiewer log of the borehole wall can provide high resolution data on the orientation and apparent width of fractures. In situ hydraulic tests of single fractures or fracture zones isolated by packers provide quantitative information on permeability, extent, and interconnection. The computer analysis of digitized acoustic waveforms has identified a part of the waveform that has amplitude variations related to permeabilities measured in the boreholes by packer tests. 38 refs., 37 figs., 4 tabs

US team measurements during the June 1987 experimental HT release at the Chalk River Nuclear Laboratories, Ontario, Canada

International Nuclear Information System (INIS)

Jalbert, R.A.; Murphy, C.E.

1988-01-01

In June 1987, an experiment was performed at the Chalk River Nuclear Laboratories in Ontario, Canada, to study the oxidation of HT in the environment. The experiment involved a 30-minute release of 100 Ci of HT to the atmosphere at an elevation of one meter. The HTOHT ratios were shown to slowly increase downwind (/approximately/4 /times/ 10/sup /minus/5/ at 50 meters to almost 10/sup /minus/3 at 400 meters) as conversion of HT takes place. For several days after the release, HTO concentrations in the atmosphere remained elevated. Freeze-dried water from vegetation samples was found to be very low in HTO immediately after the release suggesting a very low direct uptake of HTO in air by vegetation. The tritiated water concentration increased during the first day, peaking during the second day (about 400 to 600 pCiml of water at 50 meters from the source) and decreasing by the end of the second day. The organically bound tritium continued to accumulate during the period following exposure (about 10 pCigm dry weight at 50 meters after two days). 4 refs., 6 figs., 2 tabs

Comments on nuclear reactor safety in Ontario

International Nuclear Information System (INIS)

1987-08-01

The Chalk River Technicians and Technologists Union representing 500 technical employees at the Chalk River Nuclear Laboratories of AECL submit comments on nuclear reactor safety to the Ontario Nuclear Safety Review. Issues identified by the Review Commissioner are addressed from the perspective of both a labour organization and experience in the nuclear R and D field. In general, Local 1568 believes Ontario's CANDU nuclear reactors are not only safe but also essential to the continued economic prosperity of the province

U.S. team measurements during the June 1987 experimental HT release at the Chalk River Nuclear Laboratories, Ontario, Canada

International Nuclear Information System (INIS)

Jalbert, R.A.; Murphy, C.E.

1988-01-01

In June 1987, an experiment was performed at the Chalk River Nuclear Laboratories in Ontario, Canada, to study the oxidation of HT in the environment. The experiment involved a 30-minute release of 3.54 TBq (95.7 Ci) of HT to the atmosphere at an elevation of one meter. The HTO/HT ratios were shown to slowly increase downwind (-- 4 x 10/sup -5/ at 50 meters to almost 10/sup -3/ at 400 meters) as conversion of HT takes place. For several days after the release, HTO concentrations in the atmosphere remained elevated. Freeze-dried water from vegetation samples was found to be very low in HTO immediately after the release suggesting a very low direct uptake of HTO in air by vegetation. The free-HTO concentration in vegetation increased during the first day, peaking during the second day (about 1.5 - 3.0 x 10/sup 4/ Bq/L at 50 meters from the source) and decreasing by the end of the second day. The organically bound tritium continued to accumulate during the period following exposure (about 400 Bq/kg dry weight at 50 meters after two days)

Response of invertebrates from the hyporheic zone of chalk rivers to eutrophication and land use.

Science.gov (United States)

Pacioglu, Octavian; Moldovan, Oana Teodora

2016-03-01

Whereas the response of lotic benthic macroinvertebrates to different environmental stressors is a widespread practice nowadays in assessing the water and habitat quality, the use of hyporheic zone invertebrates is still in its infancy. In this study, classification and regression trees analysis were employed in order to assess the ecological requirements and the potential as bioindicators for the hyporheic zone invertebrates inhabiting four lowland chalk rivers (south England) with contrasting eutrophication levels (based on surface nitrate concentrations) and magnitude of land use (based on percentage of fine sediments load and median interstitial space). Samples of fauna, water and sediment were sampled twice, during low (summer) and high (winter) groundwater level, at depths of 20 and 35 cm. Certain groups of invertebrates (Glossosomatidae and Psychomyiidae caddisflies, and riffle beetles) proved to be good indicators of rural catchments, moderately eutrophic and with high fine sediment load. A diverse community dominated by microcrustaceans (copepods and ostracods) were found as good indicators of highly eutrophic urban streams, with moderate-high fine sediment load. However, the use of other taxonomic groups (e.g. chironomids, oligochaetes, nematodes, water mites and the amphipod Gammarus pulex), very widespread in the hyporheic zone of all sampled rivers, is of limited use because of their high tolerance to the analysed stressors. We recommend the use of certain taxonomic groups (comprising both meiofauna and macroinvertebrates) dwelling in the chalk hyporheic zone as indicators of eutrophication and colmation and, along with routine benthic sampling protocols, for a more comprehensive water and habitat quality assessment of chalk rivers.

Causes of death among long-term employees of Chalk River Laboratories, 1966-1989

International Nuclear Information System (INIS)

Werner, M.M.; Myers, D.K.

1990-11-01

Data on mortality among long-term employees of Chalk River Laboratories to 1989 December 31 are reported. The 1988 Hare report, entitled The Safety of Ontario's Nuclear Power Reactors, noted that there had been a steady rise in standardized mortality ratios (SMR) for cancer among these employees in the last three successive five-year periods from 1971-75 to 1981-85. None of the SMRs was significantly different from unity; however, the apparent trend could be indicative of the development of latent cancers. The present report was prepared to see if that increasing trend in cancer SMRs continued. In the years 1986-89, the SMR for cancer among long-term male employees was exceptionally low. The wide fluctuations seen in our data over time are likely anomalies arising from the small size of the study group rather than problems arising from radiation exposures on site

Hydrogeochemical processes affecting the migration of radionuclides in a fluvial sand aquifer at the Chalk River Nuclear Laboratories

International Nuclear Information System (INIS)

Jackson, R.E.; Inch, K.J.

1980-01-01

In the mid-1950's two experimental disposals of liquid radioactive waste containing about 700 curries of strontium-90 and cesium-137 were made into pits in sandy ground at one of the disposal areas at Chalk River Nuclear Laboratories. Since then, the wastes have migrated into two nearby aquifers and have chromatographically separated into strontium-90 and cesium-137 plumes moving at velocities less than that of the transporting groundwater. Analysis of radioactively contaminated aquifer sediments showed that most of the strontium-90 is exchangeably adsorbed, primarily to feldspars and layer silicates (mainly biotite); the rest is either specifically adsorbed to iron (III) and perhaps manganese (IV) oxhydroxides or fixed to unknown sinks. Less than one half of adsorbed cesium-137 is exchangeable with 0.5 m calcium chloride; the high levels of cesium-137 adsorption and fixation are probably due to its reaction with micaceous minerals. Complexation of strontium-90 and cesium-137 does not appear to be an important factor affecting their transport or adsorption. In studies of groundwater quality or pollution, dissolved oxygen and sulfide should be measured in addition to the redox potential since it allows independent assessment of the redox levels. The latter were found to affect the mobility of multivalent transition metals and nonmetals. (DN)

AECL'S approach to managing long term liabilities at Chalk River Laboratories. Annex II

International Nuclear Information System (INIS)

Audet, M.C.

2006-01-01

Chalk River Laboratories (CRL) is a large nuclear research and development/ industrial site operated by Atomic Energy of Canada Limited (AECL). Construction of the site started in 1944, and it now includes over 100 buildings/facilities operating in various nuclear fields. A well developed decommissioning programme exists at CRL, with progress being made on decommissioning older redundant buildings, in parallel with ongoing site operations and development. The decommissioning programme is predicated on the assumption that the current nuclear operations will continue over a 100 year operating period, but with a decline towards the end of the period. Although decommissioning and remediation work will be carried out throughout the operational period, residual levels of activity remaining in a few areas will require institutional control (IC) for an assumed period of 300 years. The intention is to complete all necessary active remediation work before the start of the IC period and thereafter rely only on passive means to reduce residual contamination to levels that do not require IC measures. The latter include environmental monitoring, active and passive controls to prevent intrusion, and management controls to prohibit access or development. A formal information and records management programme at CRL has been initiated. (author)

Field studies of radionuclide transport at the Chalk River Laboratories

International Nuclear Information System (INIS)

Champ, D.R.; Killey, R.W.D.; Moltyaner, G.L.

1991-01-01

In this paper the authors summarize the results of: in situ field column experiments to study the transport behaviour of several long-lived radionuclides, 4 natural gradient non-reactive radiotracer injection experiments at the Chalk River Laboratories (CRL) Twin Lake Tracer Test Site, and a model validation study that used data for 90 Sr from two well-defined contaminated groundwater flow systems at CRL. The paper also describes a current re-evaluation of radionuclide release and transport from a 1960 experimental burial (in a CRL sand aquifer) of glass blocks containing fission and activation products. (J.P.N.)

The Chalk River Tritium Extraction Plant

International Nuclear Information System (INIS)

Holtslander, W.J.; Harrison, T.E.; Spagnolo, D.A.

1990-01-01

The Chalk River Tritium Extraction Plant for removal of tritium from heavy water is described. Tritium is present in the heavy water from research reactors in the form of DTO at a concentration in the range of 1-35 Ci/kg. It is removed by a combination of catalytic exchange to transfer the tritium from DTO to DT, followed by cryogenic distillation to separate and concentrate the tritium to T 2 . The tritium product is reacted with titanium and packaged for transportation and storage as titanium tritide. The plant processes heavy water at a rate of 25 kg/h and removes 80% of the tritium and 90% of the protium per pass. Catalytic exchange is carried out in the liquid phase using a proprietary wetproofed catalyst. The plant serves two roles in the Canadian fusion program: it produces pure tritium for use in fusion research and development, and it demonstrates on an industrial scale many of the tritium technologies that are common to the tritium systems in fusion reactors (author)

The Chalk River Tritium Extraction Plant

Energy Technology Data Exchange (ETDEWEB)

Holtslander, W J; Harrison, T E; Spagnolo, D A

1990-07-01

The Chalk River Tritium Extraction Plant for removal of tritium from heavy water is described. Tritium is present in the heavy water from research reactors in the form of DTO at a concentration in the range of 1-35 Ci/kg. It is removed by a combination of catalytic exchange to transfer the tritium from DTO to DT, followed by cryogenic distillation to separate and concentrate the tritium to T{sub 2}. The tritium product is reacted with titanium and packaged for transportation and storage as titanium tritide. The plant processes heavy water at a rate of 25 kg/h and removes 80% of the tritium and 90% of the protium per pass. Catalytic exchange is carried out in the liquid phase using a proprietary wetproofed catalyst. The plant serves two roles in the Canadian fusion program: it produces pure tritium for use in fusion research and development, and it demonstrates on an industrial scale many of the tritium technologies that are common to the tritium systems in fusion reactors (author)

Regional transport of radioxenon released from the Chalk River Laboratories medical isotope facility

International Nuclear Information System (INIS)

Christine Johnson; Steven Biegalski

2015-01-01

An examination of proposed sampling sites near Chalk River Laboratories in Ontario, Canada is performed by considering the regional transport of radioxenon using atmospheric dispersion modeling. The local geography is considered, as are the local meteorological conditions during the summer months. In particular the impacts of predicted conditions on the imprinting of atmospheric radioxenon into the subsurface are considered and weighed against site proximity, geography, and geology. (author)

Effluent and environmental monitoring of Chalk River Laboratories

Energy Technology Data Exchange (ETDEWEB)

Pilgrim, T.; De Waele, C.; Gallagher, C. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

2014-07-01

Atomic Energy of Canada Limited's (AECL's) Environmental Protection Program has been gathering environmental monitoring data at its Chalk River Laboratories (CRL) for over 60 years. The comprehensive effluent and environmental monitoring program at CRL consists of more than 600 sampling locations, including the Ottawa River, with approximately 60,000 analyses performed on air and liquid effluent parameters each year. Monitoring for a variety of radiological and non-radiological parameters is regularly conducted on various media, including ambient air, foodstuff (e.g. milk, fish, garden produce, large game, and farm animals), groundwater, Ottawa River water and other surface water on and off-site. The purpose of the monitoring program is to verify that past and current radiological and non-radiological emissions derived from AECL operations and activities, such as process water effluent into the Ottawa River, are below regulatory limits and demonstrate that CRL operations do not negatively affect the quality of water on or leaving the site. In fact, ongoing program reports demonstrate that radiological emissions are well below regulatory limits and have been declining for the past five years, and that non-radiological contaminants do not negatively affect the quality of water on and off the site. Two updated Canadian Standards Association (CSA) standards for Effluent and Environmental monitoring have come into effect and have resulted in some changes to the AECL Program. This presentation will discuss effluent and surface water monitoring results, the observed trends, the changes triggered by the CSA standards, and a path forward for the future. (author)

Atmospherically dispersed radiocarbon at the Chalk River Laboratories

International Nuclear Information System (INIS)

Milton, G.M.; Brown, R.M.; Repta, C.J.W.; Selkirk, C.J.

1996-01-01

A small percentage of the total radiocarbon produced by the NRX and NRU experimental reactors at the Chalk River Laboratories has been vented from the main reactor stack and atmospherically dispersed across the site. Surveys conducted in 1982-83 and 1993-94 have shown that atmospheric levels more than 50 m from the stack are never greater than 600 Bq.kg -1 carbon above the natural background level, falling to near-global atmospheric levels at the site boundaries roughly 7 km away. A dispersion factor > 1.2 x 10 6 m 3 .s -1 at ∼ 0.75 km distance from the point of emission is calculated on the basis of recent in-stack monitoring. Analysis of growth rings in on-site trees has provided an opportunity to search for correlations of 14 C output summer power production and/or moderator losses. (author). 16 refs., 14 tabs., 11 figs

Trial coring in LLRW trenches at Chalk River

International Nuclear Information System (INIS)

Donders, R.E.; Killey, R.W.D.; Franklin, K.J.; Strobel, G.S.

1996-11-01

As part of a program to better characterize the low-hazard radioactive waste managed by AECL at Chalk River Laboratories, coring techniques in waste trenches are being assessed. Trial coring has demonstrated that sampling in waste regions is possible, and that boreholes can be placed through the waste trenches. Such coring provides a valuable information-gathering technique. Information available from trench coring includes: trench cover depth, waste region depth, waste compaction level, and detailed stratigraphic data; soil moisture content and facility drainage performance; borehole gamma logs that indicate radiation levels in the region of the borehole; biochemical conditions in the waste regions, vadose zone, and groundwater; site specific information relevant to contaminant migration modelling or remedial actions; information on contaminant releases and inventories. Boreholes through the trenches can also provide a means for early detection of potential contaminant releases. (author). 4 refs., 4 tabs., 4 figs

Deep waters : the Ottawa River and Canada's nuclear adventure

International Nuclear Information System (INIS)

Krenz, F.H.K.

2004-01-01

Deep Waters is an intimate account of the principal events and personalities involved in the successful development of the Canadian nuclear power system (CANDU), an achievement that is arguably one of Canada's greatest scientific and technical successes of the twentieth century. The author tells the stories of the people involved and the problems they faced and overcame and also relates the history of the development of the town of Deep River, built exclusively for the scientists and employees of the Chalk River Project and describes the impact of the Project on the traditional communities of the Ottawa Valley. Public understanding of nuclear power has remained confused, yet decisions about whether and how to use it are of vital importance to Canadians today - and will increase in importance as we seek to maintain our standard of living without doing irreparable damage to the environment around us. Deep Waters examines the issues involved in the use of nuclear power without over-emphasizing its positive aspects or avoiding its negative aspects.

Drivers of abundance and community composition of benthic macroinvertebrates in Ottawa River sediment near Chalk River Laboratories

Energy Technology Data Exchange (ETDEWEB)

Bond, M.J.; Rowan, D.; Silke, R.; Carr, J., E-mail: bondm@aecl.ca [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

2013-12-15

The Ottawa River has received effluent from Chalk River Laboratories (CRL) for more than 60 years. Some radionuclides and contaminants released in effluents are bound rapidly to particles and deposited in bottom sediments where they may be biologically available to benthic invertebrates and other aquatic biota. As part of a larger ecological assessment, we assess the potential impact of contaminated sediments in the vicinity of CRL on local benthic community structure. Using bivariate and multivariate approaches, we demonstrate that CRL operations have had little impact on the local benthic community. Despite elevated anthropogenic radionuclide activity concentrations in sediment near CRL's process outfall, the benthic community is no less abundant or diverse than what is observed upstream at background levels. The Ottawa River benthic invertebrate community is structured predominantly by natural physical and biological conditions in the sediment, specifically sediment water content and organic content. These natural habitat conditions have a stronger influence on macroinvertebrate communities than sediment contamination. (author)

Analysis of the Pelletron charging chain break in the Chalk River MP tandem accelerator

International Nuclear Information System (INIS)

Burn, N.; Greiner, B.F.; Coleman, C.E.

1980-11-01

On February 7, 1980 one of the three Pelletron charging chains in the Low Energy end of the Chalk River MP Tandem Accelerator broke during normal operation. The chains had been in use for 38 000 h at the time of the break. Tensile tests were carried out on pieces of the broken chain as well as unused pieces of chain. Several possible reasons for the chain break are suggested; ways of improving performance and reliability are proposed. (auth)

Status of the Chalk River superconducting heavy-ion cyclotron

International Nuclear Information System (INIS)

Ormrod, J.H.; Bigham, C.B.; Heighway, E.A.; Hoffmann, C.R.; Hulbert, J.A.; Schneider, H.R.

1982-01-01

The Chalk River four-sector K=520 superconducting cyclotron is designed to accelerate all ions from lithium (to 50 MeV/u) to uranium (to 10 MeV/u) using a 13 MV tandem Van de Graaff as injector. After an extended shutdown the magnet has been reassembled and field measurements resumed. During the shutdown a ground fault between the superconducting coil and its container was removed, the flutter poles were shimmed and the remaining trim rod holes were bored in them, the 104 trim rods with their holders were installed and the cryostat inner wall was modified to accept the radiofrequency accelerating structure. Experiments on the radiofrequency accelerating system, cryopumps, electrostatic deflector and superconducting windings for the magnetic channel are done in separate test chambers. Recent results and the status of all subsystems are given

Programme of research into the management and storage of radioactive waste. Single fracture experiment at Chalk River

International Nuclear Information System (INIS)

Bourke, P.J.

1984-01-01

A field experiment was carried out at Chalk river to measure the transport of bromine and strontium through a fracture in granite. Retardation of strontium transport by sorption onto the rock was also measured. Data was obtained for bromine but no useful data was obtained for strontium due to failure of the hydraulic equipment. (U.K.)

Foil changer for the Chalk River superconducting cyclotron

International Nuclear Information System (INIS)

Hoffmann, C.R.; Kilborn, R.I.; Mouris, J.E.; Proulx, D.R.; Weaver, J.F.

1985-01-01

Capture of an injected beam in the Chalk River superconducting cyclotron requires that a carbon stripping foil be accurately placed in a dee to intercept the incoming beam. Foil radial position must be precisely adjustable and foils must be easily replaced. A foil changing apparatus has been designed, built and tested to meet these requirements. The main components are a supply magazine, a transport system, and unloading and loading mechanisms. The magazine is on top of the cyclotron. It holds 300 foils and can be isolated from machine vacuum for refilling. Each foil is mounted on a stainless steel frame. A stainless steel roller chain fitted with 33 copper sleeves (shrouds) carries foils, one per shroud, down a dee stem to the midplane. A 12-bit absolute optical shaft encoder senses foil position. To replace a foil a shroud is positioned at the top of the cyclotron, a foil is removed, and another is transferred from the magazine to the empty shroud. Three stepping motors and associated electronics provide mechanical drive and are interfaced with a CAMAC control system

The Chalk River helium jet and skimmer system

International Nuclear Information System (INIS)

Schmeing, H.; Koslowsky, V.; Wightman, M.; Hardy, J.C.; MacDonald, J.A.; Faestermann, T.; Andrews, H.R.; Geiger, J.S.; Graham, R.L.

1976-01-01

A helium jet and skimmer system intended as an interface between a target location at the Chalk River tandem accelerator and the ion source of an on-line separator presently under construction has been developed. The system consists of a target chamber, a 125 cm long capillary, and a one stage skimmer chamber. The designs of the target and skimmer chambers allow one to vary a large number of independent flow and geometrical parameters with accurate reproducibility. Experiments with the β-delayed proton emitter 25 Si (tsub(1/2)=218 ms) produced in the reaction 24 Mg( 3 He,2n) 25 Si show that under optimized conditions about 75% of the reaction products leaving the target are transported to the skimmer. Of those, more than 90% pass through the skimmer orifice, which separates off 97.5% of the transport gas, helium. By introducing an additional helium flow across the skimming orifice the amount of helium separated off the transport jet can be increased to beyond 99.85%, leaving the high throughput of recoils unaffected. (Auth.)

Integrated waste plan for Chalk River Laboratories

International Nuclear Information System (INIS)

McClelland, P.; Bainbridge, I.

2011-01-01

The core missions for Chalk River Laboratories (CRL) will involve a complex suite of activities for decades to come, many of these activities resulting in production of some amount of wastes. In order to support the business of the Nuclear Laboratories there is a requirement to responsibly manage the wastes arising from these activities. Capability to develop waste stream pathway scenarios and be able to make informed strategic decisions regarding the various options for waste processing, storage and long-term management (i.e. e nabling facilities ) is necessary to discharge this responsibility in the most cost effective and sustainable manner. A holistic waste management plan integrated with the decommissioning, environmental remediation and operations programs is the desired result such that: - Waste inputs and timings are identified; - Timing of key decisions regarding enabling facilities is clearly identified; and - A defensible decision-making framework for enabling facilities is established, thereby ensuring value for Canadians. The quantities of wastes that require managing as part of the Nuclear Legacy Liabilities Program and AECL operations activities is in the range of 200,000 to 300,000 m 3 , with a yearly increase of several thousand m 3 . This volume can be classified into over thirty distinct waste streams having differing life cycle waste management pathways from generation to disposition. The time phasing of the waste management activities required for these wastes spans several decades and involves a complex array of processes and facilities. Several factors typical of wastes from the development of nuclear technology further complicate the situation. For example, there is considerable variation in the level of detail and format of waste records generated over several decades. Also, wastes were put into storage over several decades without knowledge or consideration of what the final disposition path will be. Prior to proceeding with any major new

Chalk Catchment Transit Time: Unresolved Issues

Energy Technology Data Exchange (ETDEWEB)

Darling, W. G.; Gooddy, D. C. [British Geological Survey, Crowmarsh Gifford, Wallingford, Oxfordshire (United Kingdom); Barker, J. A. [School of Civil Engineering and the Environment, University of Southampton, Southampton (United Kingdom); Robinson, M. [Centre for Ecology and Hydrology, Crowmarsh Gifford, Wallingford, Oxfordshire (United Kingdom)

2013-07-15

The mean transit time (MTT) of a catchment is the average residence time of water from rainfall to river outflow at the foot of the catchment. As such, MTT has important water quality as well as resource implications. Many catchments worldwide have been measured for MTT using environmental isotopes, yet the Chalk, an important aquifer in NW Europe, has received little attention in this regard. The catchment of the River Lambourn in southern England has been intermittently studied since the 1960s using isotopic methods. A tritium peak measured in the river during the 1970s indicates an apparent MTT of {approx}15 years, but the thick unsaturated zone (average {approx}50 m) of the catchment suggests that the MTT should be much greater because of the average downward movement through the Chalk of {approx}1 m/a consistently indicated by tritium and other tracers. Recent work in the catchment using SF{sub 6} as a residence time indicator has given groundwater ages in the narrow range 11-18 yrs, apparently supporting the river tritium data but in conflict with the unsaturated zone data even allowing for a moderate proportion of rapid bypass flow. The MTT of the catchment remains unresolved for the time being. (author)

Foil changer for the Chalk River superconducting cyclotron

International Nuclear Information System (INIS)

Hoffmann, C.R.; Kilborn, R.I.; Mouris, J.F.; Proulx, D.R.; Weaver, J.F.

1985-01-01

Capture of an injected beam in the Chalk River superconducting cyclotron requires that a carbon stripping foil be accurately placed in a dee to intercept the incoming beam. Foil radial position must be precisely adjustable and foils must be easily replaced. A foil changing apparatus has been designed, built and tested to meet these requirements. The main components are a supply magazine, a transport system, and unloading and loading mechanisms. The magazine is on top of the loading mechanisms. The magazine is on top of the cyclotron. It holds 300 foils and can be isolated from machine vacuum for refilling. Each foil is mounted on a stainless steel frame. A stainless steel roller chain fitted with 33 copper sleeves (shrouds) carries foils, one per shroud, down a dee stem to the midplane. A 12-bit absolute optical shaft encoder senses foil position. To replace a foil a shroud is positioned at the top of the cyclotron, a foil is removed, and another is transferred from the magazine to the empty shroud. Three stepping motors and associated electronics provide mechanical drive and are interfaced with a CAMAC control system

Electrostatic deflector development at the Chalk River superconducting cyclotron

International Nuclear Information System (INIS)

Diamond, W.T.; Mitchel, G.R.; Almeida, J.; Schmeing, H.

1991-01-01

An electrostatic deflector is used to extract heavy-ion beans from the Chalk River superconducting cyclotron. Deflector voltages up to 100 kV across a 7 m gap (143 kV/cm) are needed to extract the full range of beams that the cyclotron is designed to accelerate. This goal remains a challenge, but substantial progress has been made over the past year. Voltages over 90 kV have been reliably maintained over a 7.5 mm gap with a magnetic field of 3 T. Voltages of 74 kV have been used with a reduced gap of 4.75 mm (corresponding to a field greater than 150 kV/cm) to extract beams with magnetic fields up to 4.25 T. Major progress was achieved when the authors introduced a water-cooled, negative high-voltage electrode, and changed the sparking plates and the thin septum from molybdenum to stainless steel. Efforts are continuing to attain a field of at least 143 kV/cm over a gap of at least 6 mm width

Distribution of Linear Alkylbenzenes (LABs in Sediments of Sarawak and Sembulan Rivers, Malaysia

Directory of Open Access Journals (Sweden)

Sami Muhsen Magam

2012-01-01

Full Text Available The current study is one of the first studies evaluating the levels of linear alkylbenzenes (LABs in surface sediments of Sarawak and Sembulan rivers which are located in the east coast of Malaysia. The LABs, which are molecular tracers of sewage contamination, were measured in 15 surface sediment samples collected from these rivers. The samples were extracted, fractioned and analyzed by gas chromatography mass spectrometry (GC-MS. The findings revealed that the concentrations of ∑LABs ranged from 156.47 to 7386.19 ng/g dry weight (dw in the sediments of Sarawak River and from 643.18 to 5567.12 ng/g dw in the sediments of Sembulan River. The highest LABs levels were detected in the sediments collected from the sampling location SS9 in Sembulan River whereas the lowest levels were observed in the SS1 sampling location in Sarawak River. The I/E ratios (ratio of internal to external isomers of LABs for Sarawak River sediments ranged from 0.52 to 0.98 while for Sembulan River they fell within the range 0.87-1.79. The I/E ratio at the sampling station SS4 was much lower than the I/E ratios at the other stations, thus indicating that the wastewater discharged into Sarawak River from the areas surrounding station SS4 was poorly treated.

Purification and solidification of reactor wastes at a Canadian nuclear generating station

International Nuclear Information System (INIS)

Buckley, L.P.; Burt, D.A.

1981-01-01

The study aimed at development and demonstration of volume reduction and solidification of CANDU reactor wastes has been underway at Chalk River Nuclear Laboratories in the Province of Ontario, Canada. The study comprises membrane separation processes, evaporator appraisal and immobilization of concentrated wastes in bitumen. This paper discusses the development work with a wiped-film evaporator and the successful completion of demonstration tests at Douglas Point Nuclear Generating Station. Heavy water from the moderator system was purified and wastes arising from pump bowl decontamination were immobilized in bitumen with the wiped-film evaporator that was used in the development tests at Chalk River

Low-level radioactive river sediment particles originating from the Chalk river nuclear site carry a mixture of radionuclides and metals

Energy Technology Data Exchange (ETDEWEB)

Lind, Ole Christian; Cagno, Simone; Salbu, Brit [Norwegian University of Life Sciences - NMBU, Center of Excellence in Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Aas (Norway); Falkenberg, Gerald [Photon science, DESY, Hamburg (Germany); Janssens, Koen; Nuyts, Gert; Vanmeert, Frederik [AXIL, Department of Chemistry, University of Antwerpen (Belgium); Jaroszewicz, Jakub [Faculty of Materials Science and Engineering, Warsaw University of Technology, Warsaw (Poland); Priest, Nicholas D.; Audet, Marc [Nuclear Science Division, AECL Chalk River Laboratories (Canada)

2014-07-01

The Chalk River Laboratory of Atomic Energy of Canada Ltd., site is located on the Ottawa River approximately 200 km northwest of Ottawa, Canada. The site has two large research reactors: NRX, which operated from 1947 to 1991 and NRU, which continues to operate and is used to produce a significant fraction of the world's supply of medical isotopes. During the course of the operation of the NRX reactor small quantities of radioactive particles were discharged to the Ottawa River through a process sewer discharge pipe. These are now located in river bed sediments within a 0.08 km² area close to the discharge pipe. In the present study, selected particles were isolated from riverbed sediments. These were then characterized by environmental scanning electron microscopy with energy dispersive micro X-ray analysis (ESEM-EDX). This was undertaken to obtain information on particle size, structure and the distribution of elements across particle surfaces. Based on the results of ESEM-EDX, particles were selected for X-ray absorption nano-tomography analysis, which provides videos showing the 3D density distribution of the particles. Furthermore, 2D and 3D Synchrotron Radiation based X-ray techniques (micro-X-ray fluorescence; micro-XRF, micro-X-ray absorption near edge spectroscopy; micro-XANES and micro-X-ray diffraction; micro-XRD) with submicron resolution (beam size 0.5 μm) were employed to investigate the elemental and phase composition (micro-XRF/XRD) and oxidation states (micro-XANES) of matrix elements with high spatial resolution and sensitivity. Results show that the particles investigated so far varied according to: 1) <~40 μm diameter sized U fuel particles similar in structure to particles observed from Chernobyl and Krasnoyarsk-26 and 2) larger particles with diameters up to several hundred μm. The larger particles comprised a matrix of low density, sediment material with high density inclusions that contained a range of metals including Cu, Cr, As

Development of an Integrated Waste Plan for Chalk River Laboratories - 13376

International Nuclear Information System (INIS)

Jones, L.

2013-01-01

To further its Strategic Planning, the Atomic Energy of Canada Limited (AECL) required an effective approach to developing a fully integrated waste plan for its Chalk River Laboratories (CRL) site. Production of the first Integrated Waste Plan (IWP) for Chalk River was a substantial task involving representatives from each of the major internal stakeholders. Since then, a second revision has been produced and a third is underway. The IWP remains an Interim IWP until all gaps have been resolved and all pathways are at an acceptable level of detail. Full completion will involve a number of iterations, typically annually for up to six years. The end result of completing this process is a comprehensive document and supporting information that includes: - An Integrated Waste Plan document summarizing the entire waste management picture in one place; - Details of all the wastes required to be managed, including volume and timings by waste stream; - Detailed waste stream pathway maps for the whole life-cycle for each waste stream to be managed from pre-generation planning through to final disposition; and - Critical decision points, i.e. decisions that need to be made and timings by when they need to be made. A waste inventory has been constructed that serves as the master reference inventory of all waste that has been or is committed to be managed at CRL. In the past, only the waste that is in storage has been effectively captured, and future predictions of wastes requiring to be managed were not available in one place. The IWP has also provided a detailed baseline plan at the current level of refinement. Waste flow maps for all identified waste streams, for the full waste life cycle complete to disposition have been constructed. The maps identify areas requiring further development, and show the complexities and inter-relationships between waste streams. Knowledge of these inter-dependencies is necessary in order to perform effective options studies for enabling

Magnetic field related mechanical tolerances for the proposed Chalk River superconducting heavy-ion cyclotron

International Nuclear Information System (INIS)

Heighway, E.A.; Chaplin, K.R.

1977-11-01

A four sector azimuthally varying field cyclotron with superconducting main coils has been proposed as a heavy-ion post-accelerator for the Chalk River MP Tandem van de Graaff. The radial profile of the average axial field will be variable using movable steel trim rods. The field errors due to coil, trim rod and flutter pole imperfections are calculated. Those considered are errors in the axial field, first and second azimuthal harmonic axial fields, transverse field and first azimuthal harmonic transverse field. Such fields induce phase slip, axial or radial coherent oscillations and can result in axial or radial beam instability. The allowed imperfections (tolerances) required to retain stability and maintain acceptably small coherent oscillation amplitudes are calculated. (author)

Coincidence of needs in radiological and toxicological protection

International Nuclear Information System (INIS)

Osborne, R.V.

1988-01-01

Research needs for radiological protection and research programs that have evolved to meet these needs parallel closely those in the chemical toxicology field. The similarity of these needs is described as perceived from the radiological side. Further, the frame work for radiologically-related research, out lines of the research programs, and the development of the facilities at Chalk River Nuclear Labs were presented

Radiochemistry Lab Decommissioning and Dismantlement. AECL, Chalk River Labs, Ontario, Canada

International Nuclear Information System (INIS)

Kenny, Stephen

2008-01-01

Atomic Energy of Canada (AECL) was originally founded in the mid 1940's to perform research in radiation and nuclear areas under the Canadian Defense Department. In the mid 50's The Canadian government embarked on several research and development programs for the development of the Candu Reactor. AECL was initially built as a temporary site and is now faced with many redundant buildings. Prior to 2004 small amounts of Decommissioning work was in progress. Many reasons for deferring decommissioning activities were used with the predominant ones being: 1. Reduction in radiation doses to workers during the final dismantlement, 2. Development of a long-term solution for the management of radioactive wastes in Canada, 3. Financial constraints presented by the number of facilities shutdown that would require decommissioning funds and the absence of an approved funding strategy. This has led to the development of a comprehensive decommissioning plan that is all inclusive of AECL's current and legacy liabilities. Canada does not have a long-term disposal site; therefore waste minimization becomes the driving factor behind decontamination for decommissioning before and during dismantlement. This decommissioning job was a great learning experience for decommissioning and the associated contractors who worked on this project. Throughout the life of the project there was a constant focus on waste minimization. This focus was constantly in conflict with regulatory compliance primarily with respect to fire regulations and protecting the facility along with adjacent facilities during the decommissioning activities. Discrepancies in historical documents forced the project to treat every space as a contaminated space until proven differently. Decommissioning and dismantlement within an operating site adds to the complexity of the tasks especially when it is being conducted in the heart of the plant. This project was very successful with no lost time accidents in over one hundred

Evaluation of distribution and sources of sewage molecular marker (LABs) in selected rivers and estuaries of Peninsular Malaysia.

Science.gov (United States)

Magam, Sami M; Zakaria, Mohamad Pauzi; Halimoon, Normala; Aris, Ahmad Zaharin; Kannan, Narayanan; Masood, Najat; Mustafa, Shuhaimi; Alkhadher, Sadeq; Keshavarzifard, Mehrzad; Vaezzadeh, Vahab; Sani, Muhamad S A; Latif, Mohd Talib

2016-03-01

This is the first extensive report on linear alkylbenzenes (LABs) as sewage molecular markers in surface sediments collected from the Perlis, Kedah, Merbok, Prai, and Perak Rivers and Estuaries in the west of Peninsular Malaysia. Sediment samples were extracted, fractionated, and analyzed using gas chromatography mass spectrometry (GC-MS). The concentrations of total LABs ranged from 68 to 154 (Perlis River), 103 to 314 (Kedah River), 242 to 1062 (Merbok River), 1985 to 2910 (Prai River), and 217 to 329 ng g(-1) (Perak River) dry weight (dw). The highest levels of LABs were found at PI3 (Prai Estuary) due to the rapid industrialization and population growth in this region, while the lowest concentrations of LABs were found at PS1 (upstream of Perlis River). The LABs ratio of internal to external isomers (I/E) in this study ranged from 0.56 at KH1 (upstream of Kedah River) to 1.35 at MK3 (Merbok Estuary) indicating that the rivers receive raw sewage and primary treatment effluents in the study area. In general, the results of this paper highlighted the necessity of continuation of water treatment system improvement in Malaysia.

Nuclear magnetic resonance and sound velocity measurements of chalk saturated with magnesium rich brine

DEFF Research Database (Denmark)

Katika, Konstantina; Alam, Mohammad Monzurul; Fabricius, Ida Lykke

2013-01-01

The use of low field Nuclear Magnetic Resonance (NMR) to determine petrophysical properties of reservoirs has proved to be a good technique. Together with sonic and electrical resistivity measurements, NMR can contribute to illustrate the changes on chalk elasticity due to different pore water...... solutions of the same ionic strength. Saturation with a solution that contained divalent ions caused a major shift on the distribution of the relaxation time. The changes were probably due to precipitats forming extra internal surface in the sample. Sonic velocities were relatively low in the MgCl2 solution...

A Nuclear Scale System Based on LabVIEW

International Nuclear Information System (INIS)

Liu Shixing; Gu Qindong

2009-01-01

Nuclear mass scales measure the weight of materials which absorb and attenuate the nuclear radiation when the low energy γ-ray through it and is a non-contact continuous measurement device with simple structure and reliable operation. LabVIEW as a graphical programming language is a standard data acquisition and instrument control software. Based on the principle of nuclear mass scale measuring system, monitoring software for nuclear scale system is designed using LabVIEW programming environment. Software architecture mainly composed of three basic modules which include the monitoring software, databases and Web services. It achieves measurement data acquisition, status monitoring, and data management and has networking functions. (authors)

NRX and NRU reactor research facilities and irradiation and examination charges

International Nuclear Information System (INIS)

1960-08-01

This report details the irradiation and examination charges on the NRX and NRU reactors at the Chalk River Nuclear Labs. It describes the NRX and NRU research facilities available to external users. It describes the various experimental holes and loops available for research. It also outlines the method used to calculate the facilities charges and the procedure for applying to use the facilities as well as the billing procedures.

ChalkBoard: Mapping Functions to Polygons

Science.gov (United States)

Matlage, Kevin; Gill, Andy

ChalkBoard is a domain specific language for describing images. The ChalkBoard language is uncompromisingly functional and encourages the use of modern functional idioms. ChalkBoard uses off-the-shelf graphics cards to speed up rendering of functional descriptions. In this paper, we describe the design of the core ChalkBoard language, and the architecture of our static image generation accelerator.

Likely-clean concrete disposition at Chalk River Laboratories

International Nuclear Information System (INIS)

Betts, J.A.

2011-01-01

The vast majority of wastes produced at nuclear licensed sites are no different from wastes produced from other traditional industrial activities. Radiation and contamination control practices ensure that the small amounts of waste materials that contain a radiation and or contamination hazard are segregated and managed appropriately according to the level of hazard. Part of the segregation process involves additional clearance checks of wastes generated in areas where the potential to become radioactively contaminated exists, but is very small and contamination control practices are such that the wastes are believed to be 'likely-clean'. This important clearance step helps to ensure that radioactive contamination is not inadvertently released during disposition of inactive waste materials. Clearance methods for bagged likely-clean wastes (i.e. small volumes of low density wastes) or discreet non-bagged items are well advanced. Clearance of bagged likely-clean wastes involves measuring small volumes of bagged material within purpose built highly sensitive bag monitors. For non-bagged items the outer surfaces are scanned to check for surface contamination using traditional hand-held contamination instrumentation. For certain very bulky and porous materials (such as waste concrete), these traditional clearance methods are impractical or not fully effective. As a somewhat porous (and dense) material, surface scanning cannot always be demonstrated to be conclusive. In order to effectively disposition likely-clean concrete, both the method of clearance (i.e. conversion from likely-clean to clean) and method of disposition have to be considered. Likely-clean concrete wastes have been produced at Chalk River Laboratories (CRL) from demolitions of buildings and structures, as well as small amounts from site maintenance activities. A final disposition method for this material that includes the secondary clearance check that changes the classification of this

Likely-clean concrete disposition at Chalk River Laboratories

Energy Technology Data Exchange (ETDEWEB)

Betts, J.A. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

2011-07-01

The vast majority of wastes produced at nuclear licensed sites are no different from wastes produced from other traditional industrial activities. Radiation and contamination control practices ensure that the small amounts of waste materials that contain a radiation and or contamination hazard are segregated and managed appropriately according to the level of hazard. Part of the segregation process involves additional clearance checks of wastes generated in areas where the potential to become radioactively contaminated exists, but is very small and contamination control practices are such that the wastes are believed to be 'likely-clean'. This important clearance step helps to ensure that radioactive contamination is not inadvertently released during disposition of inactive waste materials. Clearance methods for bagged likely-clean wastes (i.e. small volumes of low density wastes) or discreet non-bagged items are well advanced. Clearance of bagged likely-clean wastes involves measuring small volumes of bagged material within purpose built highly sensitive bag monitors. For non-bagged items the outer surfaces are scanned to check for surface contamination using traditional hand-held contamination instrumentation. For certain very bulky and porous materials (such as waste concrete), these traditional clearance methods are impractical or not fully effective. As a somewhat porous (and dense) material, surface scanning cannot always be demonstrated to be conclusive. In order to effectively disposition likely-clean concrete, both the method of clearance (i.e. conversion from likely-clean to clean) and method of disposition have to be considered. Likely-clean concrete wastes have been produced at Chalk River Laboratories (CRL) from demolitions of buildings and structures, as well as small amounts from site maintenance activities. A final disposition method for this material that includes the secondary clearance check that changes the classification of this

HTO and OBT activity concentrations in soil at the historical atmospheric HT release site (Chalk River Laboratories)

International Nuclear Information System (INIS)

Kim, S.B.; Bredlaw, M.; Korolevych, V.Y.

2012-01-01

Tritium is routinely released by the Chalk River Laboratories (CRL) nuclear facilities. Three International HT release experiments have been conducted at the CRL site in the past. The site has not been disturbed since the last historical atmospheric testing in 1994 and presents an opportunity to assess the retention of tritium in soil. This study is devoted to the measurement of HTO and OBT activity concentration profiles in the subsurface 25 cm of soil. In terms of soil HTO, there is no evidence from the past HT release experiments that HTO was retained. The HTO activity concentration in the soil pore water appears similar to concentrations found in background areas in Ontario. In contrast, OBT activity concentrations in soil at the same site were significantly higher than HTO activity concentrations in soil. Elevated OBT appears to reside in the top layer of the soil (0–5 cm). In addition, OBT activity concentrations in the top soil layer did not fluctuate much with season, again, quite in contrast with soil HTO. This result suggests that OBT activity concentrations retained the signature of the historical tritium releases. Highlights: ► At the historical HT release site, HTO and OBT activity concentrations in soil depths were investigated. ► Most organically bound tritium exists in the top layer of the soil. ► The results indicated that OBT activity concentrations can be reflective of historical tritium releases into the environment.

Chalk as a reservoir

DEFF Research Database (Denmark)

Fabricius, Ida Lykke

, and the best reservoir properties are typically found in mudstone intervals. Chalk mudstones vary a lot though. The best mudstones are purely calcitic, well sorted and may have been redeposited by traction currents. Other mudstones are rich in very fine grained silica, which takes up pore space and thus...... basin, so stylolite formation in the chalk is controlled by effective burial stress. The stylolites are zones of calcite dissolution and probably are the source of calcite for porefilling cementation which is typical in water zone chalk and also affect the reservoirs to different extent. The relatively...... have hardly any stylolites and can have porosity above 40% or even 50% and thus also have relatively high permeability. Such intervals have the problem though, that increasing effective stress caused by hydrocarbon production results in mechanical compaction and overall subsidence. Most other chalk...

Slope failure of chalk channel margins

DEFF Research Database (Denmark)

Gale, A.; Anderskouv, Kresten; Surlyk, Finn

2015-01-01

provide evidence for recurring margin collapse of a long-lived Campanian channel. Compressionally deformed and thrust chalk hardgrounds are correlated to thicker, non-cemented chalk beds that form a broad, gentle anticline. These chalks represent a slump complex with a roll-over anticline of expanded, non......-cemented chalk in the head region and a culmination of condensed hardgrounds in the toe region. Observations strongly suggest that the slumping represents collapse of a channel margin. Farther northwards, the contemporaneous succession shows evidence of small-scale penecontemporaneous normal faulting towards...

Analysis on functions of mobile nuclear emergency monitoring lab

International Nuclear Information System (INIS)

Lai Yongfang; Wang Yonghong; Gao Jing; Sun Jian

2012-01-01

According to the fundamental purpose and mission of nuclear emergency monitoring and based on technological aspects, this paper discusses and analyses the functions and basic requirements on equipment in mobile radiation measurement lab in nuclear emergency response. (authors)

Whiteshell labs closure: crisis or opportunity?

International Nuclear Information System (INIS)

Simpson, L.

2003-01-01

L. Simpson, Mayor, Local Government District of Pinawa, Manitoba, described the impacts and public concerns produced by a hastily planned and executed withdrawal of the primary employer from a dependent company town. The Whiteshell Laboratories of the Crown corporation Atomic Energy of Canada Limited (AECL) were established in Eastern Manitoba in 1963, and Pinawa was created 15 kilometres away. Located in a provincial park region, Pinawa has also become a popular holiday cottage area with 20 000 residents inside a 30-minute radius. In 1995, the AECL Reactor Safety Research Program was moved to Chalk River, and the Nuclear Waste Management Program (NWMP) was left in limbo. Commercial negotiations to go on operating business on the site broke down. The town of Pinawa, the major stakeholder, was kept at arm's length from all discussions. (author)

Nickel adsorption on chalk and calcite

DEFF Research Database (Denmark)

Belova, Dina Alexandrovna; Lakshtanov, Leonid; Carneiro, J.F.

2014-01-01

Nickel uptake from solution by two types of chalk and calcite was investigated in batch sorption studies. The goal was to understand the difference in sorption behavior between synthetic and biogenic calcite. Experiments at atmospheric partial pressure of CO2, in solutions equilibrated with calcite...... = - 1.12 on calcite and log KNi = - 0.43 and - 0.50 on the two chalk samples. The study confirms that synthetic calcite and chalk both take up nickel, but Ni binds more strongly on the biogenic calcite than on inorganically precipitated, synthetic powder, because of the presence of trace amounts...... of polysaccharides and clay nanoparticles on the chalk surface....

Compaction of microfossil and clay-rich chalk sediments

DEFF Research Database (Denmark)

Fabricius, Ida Lykke

2001-01-01

The aim of this study was to evaluate the role of microfossils and clay in the compaction of chalk facies sediments. To meet this aim, chalk sediments with varying micro texture were studied. The sediments have been tested uniaxially confined in a stainless-steel compaction cell. The sediments are......: 1) Pure carbonate chalk with mudstone texture from Stevns Klint (Denmark), 2) Relatively pure chalk sediments with varying content of microfossils from the Ontong Java Plateau (Western Pacific), 3) Clay-rich chalk and mixed sediments from the Caribbean. The tested samples were characterised...

The effect of divalent ions on the elasticity and pore collapse of chalk evaluated from compressional wave velocity and low-field Nuclear Magnetic Resonance (NMR)

DEFF Research Database (Denmark)

Katika, Konstantina; Addassi, Mouadh; Alam, Mohammad Monzurul

2015-01-01

The effects of divalent ions on the elasticity and the pore collapse of chalk were studied through rock-mechanical testing and low-field Nuclear Magnetic Resonance (NMR) measurements. Chalk samples saturated with deionized water and brines containing sodium, magnesium, calcium and sulfate ions were...... subjected to petrophysical experiments, rock mechanical testing and low-field NMR spectroscopy. Petrophysical characterization involving ultrasonic elastic wave velocities in unconfined conditions, porosity and permeability measurements, specific surface and carbonate content determination and backscatter...... electron microscopy of the materials were conducted prior to the experiments. The iso-frame model was used to predict the bulk moduli in dry and saturated conditions from the compressional modulus of water-saturated rocks. The effective stress coefficient, as introduced by Biot, was also determined from...

Open web system of Virtual labs for nuclear and applied physics

International Nuclear Information System (INIS)

Saldikov, I S; Afanasyev, V V; Petrov, V I; Ternovykh, M Yu

2017-01-01

An example of virtual lab work on unique experimental equipment is presented. The virtual lab work is software based on a model of real equipment. Virtual labs can be used for educational process in nuclear safety and analysis field. As an example it includes the virtual lab called “Experimental determination of the material parameter depending on the pitch of a uranium-water lattice”. This paper included general description of this lab. A description of a database on the support of laboratory work on unique experimental equipment which is included this work, its concept development are also presented. (paper)

Chalk effect on PVC cross-linking under irradiation

International Nuclear Information System (INIS)

Chudinova, V.V.; Guzeev, V.V.; Mozzhukhin, V.B.; Pomerantseva, Eh.G.; Nozrina, F.D.; Zhil'tsov, V.V.; Zubov, V.P.

1994-01-01

Effect of nonmodified and modified chalk on curing degree of polymer matrix was studied under-irradiation of PVC-compositions. Films of the compositions (100 mass part 7 PVC, 0-100 mas.part of chalk, 2.5 - lead sulfate, 1.5 - lead stearate and 0.3 - glycerin) were irradiated up to absorbed dose 0.1 MGy in an inert medium. Content of gel-fraction after boiling in THF was determined with use of IR spectroscopy. It was established, that intensive dehydrochlorination and polymer curing took place on chalk particle surface. Network fixed strongly chalk particles. However, chalk inhibited processes of dehydrochlorination and PVC curing, increasing amount of noncured PVC in polymer matrix

Nuclear pursuits: The scientific biography of Wilfrid Bennett Lewis

International Nuclear Information System (INIS)

Fawcett, R.

1994-01-01

The scientific life of Wilfrid Bennett Lewis. The biography covers Lewis's role in the development of radar, his tenure as the Chief Superintendent of the Telecommunications Research Establishment at Malvern through his heading of the then fledgling Canadian nuclear research facility in Chalk River, Ontario. Lewis's drive, intelligence, and remarkable organizational skills placed him at the forefront of Canada's nuclear program. His influence lead to a collaboration between Atomic Energy of Canada Limited and Ontario Hydro that ultimately resulted in the development of the CANDU reactor. His influence was also profound in the near by town of Deep River with one prime legacy being the W.B. Lewis Library. Lewis's bibliography is included in the biography

Contaminated groundwater characterization at the Chalk River Laboratories, Ontario, Canada

Energy Technology Data Exchange (ETDEWEB)

Schilk, A.J.; Robertson, D.E.; Thomas, C.W.; Lepel, E.A. [Pacific Northwest National Lab., Richland, WA (United States); Champ, D.R.; Killey, R.W.D.; Young, J.L.; Cooper, E.L. [Chalk River Labs., Chalk River, Ontario (Canada)

1993-03-01

The licensing requirements for the disposal of low-level radioactive waste (10 CFR 61) specify the performance objectives and technical requisites for federal and commercial land disposal facilities, the ultimate goal of which is to contain the buried wastes so that the general population is adequately protected from harmful exposure to any released radioactive materials. A major concern in the operation of existing and projected waste disposal sites is subterranean radionuclide transport by saturated or unsaturated flow, which could lead to the contamination of groundwater systems as well as uptake by the surrounding biosphere, thereby directly exposing the general public to such materials. Radionuclide transport in groundwater has been observed at numerous commercial and federal waste disposal sites [including several locations within the waste management area of Chalk River Laboratories (CRL)], yet the physico-chemical processes that lead to such migration are still not completely understood. In an attempt to assist in the characterization of these processes, an intensive study was initiated at CRL to identify and quantify the mobile radionuclide species originating from three separate disposal sites: (a) the Chemical Pit, which has received aqueous wastes containing various radioisotopes, acids, alkalis, complexing agents and salts since 1956, (b) the Reactor Pit, which has received low-level aqueous wastes from a reactor rod storage bay since 1956, and (c) the Waste Management Area C, a thirty-year-old series of trenches that contains contaminated solid wastes from CRL and various regional medical facilities. Water samples were drawn downgradient from each of the above sites and passed through a series of filters and ion-exchange resins to retain any particulate and dissolved or colloidal radionuclide species, which were subsequently identified and quantified via radiochemical separations and gamma spectroscopy. These groundwaters were also analyzed for anions

Canadian approach to nuclear power safety

International Nuclear Information System (INIS)

Atchison, R.J.; Boyd, F.C.; Domaratzki, Z.

1983-01-01

The development of the Canadian nuclear power safety philosophy and practice is traced from its early roots at the Chalk River Nuclear Laboratories to the licensing of the current generation of power reactors. Basic to the philosophy is a recognition that the licensee is primarily responsible for achieving a high standard safety. As a consequence, regulatory requirements have emphasized numerical safety goals and objectives and minimized specific design or operating rules. In this article the Canadian licensing process is described with a discussion of some of the difficulties encountered. Examples of specific licensing considerations for each phase of a project are included

Tritium behavior on a cultivated plot in the 1994 chronic HT release experiment at Chalk River

International Nuclear Information System (INIS)

Noguchi, H.; Yokoyama, S.; Kinouchi, N.; Murata, M.; Amano, H.; Atarashi, M.; Ichimasa, Y.; Ichimasa, M.

1995-01-01

The behavior of HT and HTO in air and surface soil has been studied extensively in the chronic HT release experiment carried out at Chalk River during the summer of 1994. HTO concentrations in air moisture and soil water collected in a cultivated plot showed similar time-variations, increasing rapidly during the first and second days and becoming gradual after the first 3-4 days. The air HTO concentration decreased during and following rainfall but recovered within a day. The rainfall reduced the HTO concentrations in ridge soil water but little in furrows. Time histories of HTO concentrations in air moisture and soil water suggest that the system was near steady-state within a continuous HT release period of 12 days, in spite of the presence of rain during the period. The air HTO concentrations on clear days showed diurnal cycles that were higher during daytime than at night. The experimental field had a very complex soil regime with respect to HT deposits. The deposits to soil surface varied depending on soil conditions. 12 refs., 5 figs

Pre-operational HTO/HT surveys in the vicinity of the Chalk River Laboratories tritium extraction plant

International Nuclear Information System (INIS)

Workman, W.J.G.; Brown, R.M.

1993-08-01

Surveys of the concentrations of HT and HTO in the atmosphere downwind of the Chalk River Laboratories reactor facilities were carried out in 1986 November, and in 1989 March, April and September under different conditions of air temperature, wind direction, and snow or vegetative cover. HT usually amounted to 1-5% of total tritium, but values up to 20% were observed, probably resulting from preferential removal of HTO. In all of the surveys, the greater persistence in the atmosphere of HT than of HTO was evident. The existing levels of HT are such that they will not be augmented significantly by chronic releases from the Tritium Extraction Plant (TEP) when it comes into operation. Hence, operation of the TEP will not facilitate studies of the environmental behaviour of chronically released HT. However, longer term studies of the distribution of HT from the existing facilities would be worthwhile. Soil and vegetation HTO levels in the study area are reported. Further studies of the distribution of tritium between the air, soil and vegetation in areas subjected to chronic exposure would be valuable

Chalk Formations as Natural Barriers towards Radionuclide Migration

DEFF Research Database (Denmark)

Pedersen, Walther Batsberg; Carlsen, Lars; Jensen, Bror Skytte

1985-01-01

A series of chalk samples from the cretaceous formation overlying the Erslev salt dome have been studied in order to establish permeabilities, porosities, dispersion-, diffusion-, and sorption characteristics of the chalk. The chalk was found to be porous (∊≈0.4), however, of rather low...

Radiation chemistry in the nuclear power reactor environment: from laboratory study to practical application

International Nuclear Information System (INIS)

Stuart, C.R.

1999-01-01

This paper discusses the work carried out at the Chalk River Nuclear Laboratories in underlying and applied radiation chemical research performed to optimise the processes occurring in the four aqueous systems in and around the core. The aqueous systems subject to radiolysis in CANDU reactors are Heat Transport System, Moderator, Liquid Zone Controls and End Shields.

Development of an Embedded Solar Tracking System with LabVIEW Motion Control

International Nuclear Information System (INIS)

Oh, Seung Jin; Hyun, Jun Ho; Oh, Won Jong; Kim, Yeong Min; Lee, Yoon Joon; Chun, Won Gee

2010-01-01

Motion control is a sub-field of automation, in which the position and/or velocity of machines are controlled using some type of device such as a hydraulic pump, linear actuator, or an electric motor. The motion control is widely used in the packaging, printing, textile, semiconductor production, and power plants. National Instruments LabVIEW is a graphical programming language that has its roots in automation control and data acquisition. Its graphical representation, similar to a process flow diagram, was created to provide an intuitive programming environment for scientist and engineers. Crystal River Nuclear Plant engineers developed automated testing system of nuclear plant control modules in an aging nuclear power plant using LabVIEW to improve performance and reliability and reduce cost. In this study, an embedded two-axis solar tracking system was developed using LabVIEW motion control module

U–Pb, Rb–Sr, and U-series isotope geochemistry of rocks and fracture minerals from the Chalk River Laboratories site, Grenville Province, Ontario, Canada

International Nuclear Information System (INIS)

Neymark, L.A.; Peterman, Z.E.; Moscati, R.J.; Thivierge, R.H.

2013-01-01

Highlights: • AECL evaluates Chalk River Laboratories site as potential nuclear waste repository. • Isotope-geochemical data for rocks and fracture minerals at CRL site are reported. • Zircons from gneiss and granite yielded U–Pb ages of 1472 ± 14 and 1045 ± 6 Ma. • WR Rb–Sr and Pb–Pb systems do not show substantial large-scale isotopic mobility. • U-series and REE data do not support oxidizing conditions at depth in the past 1 Ma. - Abstract: As part of the Geologic Waste Management Facility feasibility study, Atomic Energy of Canada Ltd. (AECL) is evaluating the suitability of the Chalk River Laboratories (CRL) site in Ontario, situated in crystalline rock of the southwestern Grenville Province, for the possible development of an underground repository for low- and intermediate-level nuclear waste. This paper presents petrographic and trace element analyses, U–Pb zircon dating results, and Rb–Sr, U–Pb and U-series isotopic analyses of gneissic drill core samples from the deep CRG-series characterization boreholes at the CRL site. The main rock types intersected in the boreholes include hornblende–biotite (±pyroxene) gneisses of granitic to granodioritic composition, leucocratic granitic gneisses with sparse mafic minerals, and garnet-bearing gneisses with variable amounts of biotite and/or hornblende. The trace element data for whole-rock samples plot in the fields of within-plate, syn-collision, and volcanic arc-type granites in discrimination diagrams used for the tectonic interpretation of granitic rocks. Zircons separated from biotite gneiss and metagranite samples yielded SHRIMP-RG U–Pb ages of 1472 ± 14 (2σ) and 1045 ± 6 Ma, respectively, in very good agreement with widespread Early Mesoproterozoic plutonic ages and Ottawan orogeny ages in the Central Gneiss Belt. The Rb–Sr, U–Pb, and Pb–Pb whole-rock errorchron apparent ages of most of the CRL gneiss samples are consistent with zircon U–Pb age and do not indicate

Adsorption Properties of Chalk Reservoir Materials

DEFF Research Database (Denmark)

Okhrimenko, Denis

/gas adsorption properties of synthetic calcium carbonate phases (calcite, vaterite and aragonite) with chalk, which is composed of biogenic calcite (>98%). In combination with data from nanotechniques, the results demonstrate the complexity of chalk behavior and the role of nanoscale clay particles. The results...

The Canadian approach to nuclear power safety

International Nuclear Information System (INIS)

Atchison, R.J.; Boyd, F.C.; Domaratski, Z.

1983-07-01

The development of the Canadian nuclear power safety philosophy and practice is traced from its early roots at the Chalk River Nuclear Laboratory to the licensing of the current generation of power reactors. Basic to the philosophy is a recognition that the primary responsibility for achieving a high standard of safety resides with the licensee. As a consequence, regulatory requirements have emphasized numerical safety goals and objectives and minimized specific design or operating rules. The Canadian licensing process is described along with a discussion of some of the difficulties encountered. Examples of specific licensing considerations for each phase of a project are included

Self Compacting Concrete with Chalk Filler

DEFF Research Database (Denmark)

Sørensen, Eigil V.

2007-01-01

Utilisation of Danish chalk filler has been investigated as a means to produce self compacting concrete (SCC) at lower strength levels for service in non aggressive environments. Stable SCC mixtures were prepared at chalk filler contents up to 60% by volume of binder to yield compressive strengths...

The Chalk River Nuclear Laboratories contingency plan -a brief description

International Nuclear Information System (INIS)

White, J.M.

1982-01-01

A brief description of the contingency plan which deals with both the on-site and off-site consequences of a serious nuclear accident is given. The off-site consequences of different size releases and the subsequent action taken by employees, radiation protection experts, municipal, Provincial and Federal authorities is described and the interaction of the various groups is discussed. (author)

Can we get a better knowledge on dissolution processes in chalk by using microfluidic chips?

Science.gov (United States)

Neuville, Amélie; Minde, Mona; Renaud, Louis; Vinningland, Jan Ludvig; Dysthe, Dag Kristian; Hiorth, Aksel

2017-04-01

mostly occurs at the surface of the sample. The reacting chalk surface is observed in situ by stereomicroscopy and by interferometry. The dissolution velocities are highly heterogeneous. To identify the mineral change of the surface, a posteriori measurements using field emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray spectroscopy (EDS). [1] Neuville et al, 2016, Xurography for microfluidics on a reactive solid, Lab on Chip, DOI: 10.1039/c6lc01253a

Nuclear waste management

International Nuclear Information System (INIS)

Wicks, G.G.; Ross, W.A.

1984-01-01

Papers from the Second International Symposium on Ceramics in Nuclear Waste Management, held during the American Ceramic Society's 85th Annual Meeting, comprise this eighth volume in the Advances in Ceramics series. The 81 papers included in this volume were compiled by George G. Wicks, of Savannah River Lab, and Wayne A. Ross, of Battelle, Pacific Northwest Labs

Nuclear Medicine at Berkeley Lab: From Pioneering Beginnings to Today (LBNL Summer Lecture Series)

International Nuclear Information System (INIS)

Budinger, Thomas

2006-01-01

Summer Lecture Series 2006: Thomas Budinger, head of Berkeley Lab's Center for Functional Imaging, discusses Berkeley Lab's rich history pioneering the field of nuclear medicine, from radioisotopes to medical imaging.

Field and numerical descriptions of fracture geometries and terminations in chalk containing chert layers and inclusions; implications for groundwater flow in Danish chalk aquifers

Science.gov (United States)

Seyum, S.

2017-12-01

This study is a description of the fracture distribution in laterally discontinuous chalk and chert layers, with an investigation on how fracture lengths and apertures vary as a function of applied stresses, material properties, and interface properties. Natural fractures intersect laterally extensive, discontinuous, chalk-chert material interfaces in 62 million-year old to 72 million-year old Chalk Group formations exposed at Stevns Klint, Denmark. Approximately one-third of Denmark's fresh water use is from chalk and limestone regional aquifers of the Chalk Group formations, where rock permeability is dominantly a function of open fracture connectivities. Fractured, centimeter- to decimeter-thick chert layers and inclusions (101 GPa elastic stiffness) are interlayered with fractured, meter-thick chalk layers (100 GPa elastic stiffness). Fractures are observed to terminate against and cross chalk-chert interfaces, affecting the vertical flow of water and pollutants between aquifers. The discontinuous and variably thin nature of chert layers at Stevns Klint effectively merges adjacent fracture-confining layers of chalk along discrete position intervals, resulting in lateral variability of fracture spacing. Finite element numerical models are designed to describe fracture interactions with stiff, chert inclusions of various shapes, thicknesses, widths, orientations, and interface friction and fracture toughness values. The models are two-dimensional with isotropic, continuous material in plane strain and uniformly applied remote principal stresses. These characteristics are chosen based on interpretations of the petrophysics of chalk and chert, the burial history of the rock, and the scale of investigation near fracture tips relative to grain sizes. The result are value ranges for relative stiffness contrasts, applied stresses, and material interface conditions that would cause fractures to cross, terminate at, or form along chalk-chert interfaces, with emphasis on

Adsorption of hydrocarbons in chalk reservoirs

Energy Technology Data Exchange (ETDEWEB)

Madsen, L.

1996-12-31

The present work is a study on the wettability of hydrocarbon bearing chalk reservoirs. Wettability is a major factor that influences flow, location and distribution of oil and water in the reservoir. The wettability of the hydrocarbon reservoirs depends on how and to what extent the organic compounds are adsorbed onto the surfaces of calcite, quartz and clay. Organic compounds such as carboxylic acids are found in formation waters from various hydrocarbon reservoirs and in crude oils. In the present investigation the wetting behaviour of chalk is studied by the adsorption of the carboxylic acids onto synthetic calcite, kaolinite, quartz, {alpha}-alumina, and chalk dispersed in an aqueous phase and an organic phase. In the aqueous phase the results clearly demonstrate the differences between the adsorption behaviour of benzoic acid and hexanoic acid onto the surfaces of oxide minerals and carbonates. With NaCl concentration of 0.1 M and with pH {approx_equal} 6 the maximum adsorption of benzoic acid decreases in the order: quartz, {alpha}-alumina, kaolinite. For synthetic calcite and chalk no detectable adsorption was obtaind. In the organic phase the order is reversed. The maximum adsorption of benzoic acid onto the different surfaces decreases in the order: synthetic calcite, chalk, kaolinite and quartz. Also a marked difference in adsorption behaviour between probes with different functional groups onto synthetic calcite from organic phase is observed. The maximum adsorption decreases in the order: benzoic acid, benzyl alcohol and benzylamine. (au) 54 refs.

Remote intelligent nuclear facility monitoring in LabVIEW

International Nuclear Information System (INIS)

Kucewicz, J.C.; Argo, P.E.; Caffrey, M.; Loveland, R.C.; McNeil, P.J.

1996-01-01

A prototype system implemented in LabVIEW for the intelligent monitoring of the movement of radioactive' material within a nuclear facility is presented. The system collects and analyzes radiation sensor and video data to identify suspicious movement of material within the facility. The facility system also transmits wavelet- compressed data to a remote system for concurrent monitoring. 2 refs., 2 figs

The use of borehole geophysical logs and hydrologic tests to characterize plutonic rock for nuclear fuel waste disposal

International Nuclear Information System (INIS)

Davison, C.C.

1984-05-01

The selection of an igneous rock body for the disposal of nuclear fuel waste will likely require the drilling and testing of a number of deep investigative boreholes in the rock body. Although coring of at least one hole at each Research Area will be essential, methods for making in situ geophysical and hydrological measurements can substitute for widespread coring and result in significant savings in time and money. A number of borehole methods have been applied to the investigation of plutonic rocks at Whiteshell Nuclear Research Establishment and Chalk River Nuclear Laboratories in Canada

Progress report, Physics Division, July 1 to September 30, 1976

International Nuclear Information System (INIS)

1976-10-01

Progress in the Physics Division, Chalk River Nuclear Laboratories, is reported for the period July 1 to September 30, 1976. Operation of the MP Tandem accelerator is described. Design highlights are provided for a proposed superconcucting cyclotron. Elastic and inelastic scattering experiments, many conducted in cooperation with other laboratories, are summarized. Activities of the Chalk River computation centre are also described. (O.T.)

To What Degree Thermal Cycles Affect Chalk Strength

DEFF Research Database (Denmark)

Livada, Tijana; Nermoen, Anders; Korsnes, Reidar Inger

triaxial cell experiments. For dry rock, no significant effects of temperature cycling was found on average tensile strength, however the range of the tensile failure stress is doubled for the samples exposed to 50 temperature cycles, as opposed to those to none. For water saturated cores, the temperature......Chalk reservoirs could potentially undergo destabilization as the result of repeated cold water injection into a hot reservoir during water flooding. Preliminary results of an ongoing study are presented in this paper, which compare the impact of temperature cycling on mechanical behavior on dry...... and water saturated chalk. Sixty disks of dry Kansas chalk exposed to different number of temperature cycles were tested for tensile strength using a Brazilian test. Changes in elastic properties as function of number of temperature cycles of the same chalk, but now saturated in water, were studied using...

Childhood leukemia around nuclear facilities

International Nuclear Information System (INIS)

1991-01-01

This Information Bulletin highlights the conclusion made from an Atomic Energy Control Board of Canada (AECB) study on the incidence of childhood leukemia near nuclear facilities. All of the locations with the nuclear facilities are located in Ontario, the nuclear generating stations at Pickering and Bruce; the uranium mines and mills in Elliot Lake; the uranium refining facility in Port Hope; and nuclear research facilities located at Chalk River plus the small nuclear power plant in Rolphton. Two conclusions are drawn from the study: 1) while the rate of childhood leukemias made be higher or lower than the provincial average, there is no statistical evidence that the difference is due to anything but the natural variation in the occurrence of the disease; and 2) the rate of occurrence of childhood leukemia around the Pickering nuclear power station was slightly greater than the Ontario average both before and after the plant opened, but this, too , could be due to the natural variation

Current status of the waste identification program at AECL's Chalk River Laboratories

International Nuclear Information System (INIS)

Csullog, G.W.; Edwards, N.W.; TerHuurne, M.A.

1998-01-01

The management of routine operating waste by Waste Management and Decommissioning (WM and D) at Atomic Energy of Canada Limited's (AECL) Chalk River Laboratories (CRL) is supported by the Waste Identification (WI) Program. The principal purpose of the WI Program is to minimize the cost and the effort associated with waste characterization and waste tracking, which are needed to optimize waste handling, storage and disposal. The major steps in the WI Program are: (1) identify and characterize the processes that generate the routine radioactive wastes accepted by WM and D - radioisotope production, radioisotope use, reactor operation, fuel fabrication, et cetera (2) identify and characterize the routine blocks of waste generated by each process or activity - the initial characterization is based on inference (process knowledge) (3) prepare customized, template data sheets for each routine waste block - templates contain information such as package type, waste material, waste type, solidifying agent, the average non-radiological contaminant inventory, the average radiological contaminant inventory, and the waste class (4) ensure generators 'use the right piece of paper with the right waste' when they transfer waste to WM and D - that is they use the correct template data sheets to transfer routine wastes, by: identifying and marking waste collection points in the generator's facility; ensuring that generators implement effective waste collection/segregation procedures; implementing standard procedures to transfer waste to WM and D; and, auditing waste collection and segregation within a generator's facility (5) determine any additional waste block characterization requirements (is anything needed beyond the original characterization by process knowledge?) This paper describes the WI Program, it provides an example of its implementation, and it summarizes the current status of its implementation for both CRL and non-CRL waste generators. (author)

Seismic architecture of the Chalk Group from onshore reflection data in eastern Denmark

DEFF Research Database (Denmark)

Moreau, Julien; Anderskouv, Kresten; Boldreel, Lars Ole

with the seismic stratigraphy. Several seismic facies are identified in the Chalk Group: the 'transparent' (white chalk), the stratified (marl-chalk alternations), the crudely stratified (flint-rich chalk) and the hummocky (bryozoan mounds). The units notably vary in thickness at a relatively small scale...... of the deformations appear to be restricted to the white chalk, whereas the stratified seismic facies are comparatively less disturbed. The origin of the structures observed in the white chalk can either be associated with the regional stress field or with differential diagenetic evolution between strata inducing...

Regional hardening of Upper Cretaceous Chalk in eastern England, UK: trace element and stable isotope patterns in the Upper Cenomanian and Turonian Chalk and their significance

Science.gov (United States)

Jeans, Christopher V.; Long, Dee; Hu, Xiu-Fang; Mortimore, Rory N.

2014-12-01

The regional hardening of the Late Cenomanian to Early Turonian Chalk of the Northern Province of eastern England has been investigated by examining the pattern of trace elements and stable carbon and oxygen isotopes in the bulk calcite of two extensive and stratigraphically adjacent units each 4 to 5 m thick of hard chalk in Lincolnshire and Yorkshire. These units are separated by a sequence, 0.3-1.3 m thick, of variegated marls and clayey marls. Modelling of the geochemistry of the hard chalk by comparison with the Standard Louth Chalk, combined with associated petrographic and geological evidence, indicates that (1) the hardening is due to the precipitation of a calcite cement, and (2) the regional and stratigraphical patterns of geochemical variation in the cement are largely independent of each other and have been maintained by the impermeable nature of the thin sequence of the clay-rich marls that separate them. Two phases of calcite cementation are recognised. The first phase was microbially influenced and did not lithify the chalk. It took place predominantly in oxic and suboxic conditions under considerable overpressure in which the Chalk pore fluids circulated within the units, driven by variations in compaction, temperature, pore fluid pressure and local tectonics. There is evidence in central and southern Lincolnshire of the loss of Sr and Mgenriched pore fluids to the south during an early part of this phase. The second phase of calcite precipitation was associated with the loss of overpressure in probably Late Cretaceous and in Cenozoic times as the result of fault movement in the basement penetrating the overlying Chalk and damaging the seal between the two chalk units. This greatly enhanced grain pressures, resulting in grain welding and pressure dissolution, causing lithification with the development of stylolites, marl seams, and brittle fractures. Associated with this loss of overpressure was the penetration of the chalk units by allochthonous

Nuclear fuels accounting interface: River Bend experience

International Nuclear Information System (INIS)

Barry, J.E.

1986-01-01

This presentation describes nuclear fuel accounting activities from the perspective of nuclear fuels management and its interfaces. Generally, Nuclear Fuels-River Bend Nuclear Group (RBNG) is involved on a day-by-day basis with nuclear fuel materials accounting in carrying out is procurement, contract administration, processing, and inventory management duties, including those associated with its special nuclear materials (SNM)-isotopics accountability oversight responsibilities as the Central Accountability Office for the River Bend Station. As much as possible, these duties are carried out in an integrated, interdependent manner. From these primary functions devolve Nuclear Fuels interfacing activities with fuel cost and tax accounting. Noting that nuclear fuel tax accounting support is of both an esoteric and intermittent nature, Nuclear Fuels-RBNG support of developments and applications associated with nuclear fuel cost accounting is stressed in this presentation

The design of virtual double-parameter nuclear spectrum acquisition system based on LabVIEW

International Nuclear Information System (INIS)

Liu Songqiu; Chen Chuan; Lei Wuhu

2001-01-01

This paper introduces the design of virtual double-parameter nuclear spectrum acquisition system based on LabVIEW and NI multifunction DAQ board, and the use of it to measure the double-parameter nuclear spectrum

Imaging the Danish Chalk Group with high resolution, 3-component seismics

Science.gov (United States)

Kammann, J.; Rasmussen, S. L.; Nielsen, L.; Malehmir, A.; Stemmerik, L.

2016-12-01

The Chalk Group in the Danish Basin forms important reservoirs to hydrocarbons as well as water resources, and it has been subject to several seismic studies to determine e.g. structural elements, deposition and burial history. This study focuses on the high quality seismic response of a survey acquired with an accelerated 45 kg weight drop and 3-component MEMS-based sensors and additional wireless vertical-type sensors. The 500 m long profile was acquired during one day close to a chalk quarry and chalk cliffs of the Stevns peninsula in eastern Denmark where the well-known K-T (Cretaceous-Tertiary) boundary and different chalk lithologies are well-exposed. With this simple and fast procedure we were able to achieve deep P-wave penetration to the base of the Chalk Group at about 900 m depth. Additionally, the CMP-processed seismic image of the vertical component stands out by its high resolution. Sedimentary features are imaged in the near-surface Danian, as well as in the deeper Maastrichtian and Upper Campanian parts of the Chalk Group. Integration with borehole data suggests that changes in composition, in particular clay content, correlate with changes in reflectivity of the seismic data set. While the pure chalk in the Maastrichtian deposits shows rather low reflectivity, succession enriched in clay appear to be more reflective. The integration of the mentioned methods gives the opportunity to connect changes in facies to the elastic response of the Chalk Group in its natural environmental conditions.

Current oil and gas production from North American Upper Cretaceous chalks

Science.gov (United States)

Scholle, Peter A.

1977-01-01

Production of oil and natural gas from North American chalks has increased significantly during the past five years, spurred by the prolific production from North Sea chalks, as well as by higher prices and improved production technology. Chalk reservoirs have been discovered in the Gulf Coast in the Austin Group, Saratoga and Annona Chalks, Ozan Formation, Selma Group, Monroe gas rock (an informal unit of Navarro age), and other Upper Cretaceous units. In the Western Interior, production has been obtained from the Cretaceous Niobrara and Greenhorn Formations. Significant, though subcommercial, discoveries of natural gas and gas condensate also have been made in the Upper Cretaceous Wyandot Formation on the Scotian Shelf of eastern Canada. All North American chalk units share a similar depositional and diagenetic history. The chalks consist primarily of whole and fragmented coccoliths with subordinate planktonic and benthonic Foraminifera, inoceramid prisms, oysters, and other skeletal grains. Most have between 10 and 35 percent HCl-insoluble residue, predominantly clay. Deposition was principally below wave base in tens to hundreds of meters of water. The diagenetic history of a chalk is critical in determining its reservoir potential. All chalk has a stable composition (low-Mg calcite) and very high primary porosity. With subsequent burial, mechanical and chemical (solution-transfer) compaction can reduce or completely eliminate pore space. The degree of loss of primary porosity in chalk sections is normally a direct function of the maximum depth to which it has been buried. Pore-water chemistry, pore-fluid pressures, and tectonic stresses also influence rates of cementation. Oil or gas reservoirs of North American chalk fall into three main groups: 1. Areas with thin overburden and significant primary porosity retention (for example, Niobrara Formation of Kansas and eastern Colorado). 2. Areas with thicker overburden but considerable fracturing. Here primary

Experience in handling concentrated tritium

International Nuclear Information System (INIS)

Holtslander, W.J.

1985-12-01

The notes describe the experience in handling concentrated tritium in the hydrogen form accumulated in the Chalk River Nuclear Laboratories Tritium Laboratory. The techniques of box operation, pumping systems, hydriding and dehydriding operations, and analysis of tritium are discussed. Information on the Chalk River Tritium Extraction Plant is included as a collection of reprints of papers presented at the Dayton Meeting on Tritium Technology, 1985 April 30 - May 2

Modelling flow and heat transfer through unsaturated chalk - Validation with experimental data from the ground surface to the aquifer

Science.gov (United States)

Thiéry, Dominique; Amraoui, Nadia; Noyer, Marie-Luce

2018-01-01

During the winter and spring of 2000-2001, large floods occurred in northern France (Somme River Basin) and southern England (Patcham area of Brighton) in valleys that are developed on Chalk outcrops. The floods durations were particularly long (more than 3 months in the Somme Basin) and caused significant damage in both countries. To improve the understanding of groundwater flooding in Chalk catchments, an experimental site was set up in the Hallue basin, which is located in the Somme River Basin (France). Unsaturated fractured chalk formation overlying the Chalk aquifer was monitored to understand its reaction to long and heavy rainfall events when it reaches a near saturation state. The water content and soil temperature were monitored to a depth of 8 m, and the matrix pressure was monitored down to the water table, 26.5 m below ground level. The monitoring extended over a 2.5-year period (2006-2008) under natural conditions and during two periods when heavy, artificial infiltration was induced. The objective of the paper is to describe a vertical numerical flow model based on Richards' equation using these data that was developed to simulate infiltrating rainwater flow from the ground surface to the saturated aquifer. The MARTHE computer code, which models the unsaturated-saturated continuum, was adapted to reproduce the monitored high saturation periods. Composite constitutive functions (hydraulic conductivity-saturation and pressure-saturation) that integrate the increase in hydraulic conductivity near saturation and extra available porosity resulting from fractures were introduced into the code. Using these composite constitutive functions, the model was able to accurately simulate the water contents and pressures at all depths over the entire monitored period, including the infiltration tests. The soil temperature was also accurately simulated at all depths, except during the infiltrations tests, which contributes to the model validation. The model was used

Chalk: composition, diagenesis and physical properties

DEFF Research Database (Denmark)

Fabricius, Ida Lykke

2007-01-01

Chalk is a sedimentary rock of unusually high homogeneity on the scale where physical properties are measured, but the properties fall in wide ranges. Chalk may thus be seen as the ideal starting point for a physical understanding of rocks in general. Properties as porosity, permeability, capillary...... involving clay, silica, and calcite are interlinked, but progress differently in different localities. This partly depends on primary sediment composition, including organic content, which may induce the formation of concretions by microbial action. The diagenetic processes also depend on water depth, rate...

Geochemical criteria for reservoir quality variations in chalk from the North Sea

International Nuclear Information System (INIS)

Kunzendorf, H.; Soerensen, P.

1989-12-01

The influence of chalk geochemistry on petrophysical parameters determining porosity and permeability is investigated. The central well TWB-8 and eastern marginal well E-lx of the North Sea Tyra gas field were chosen. Drill core sections of Upper Maastrichtian and Danian chalk were selected. Chemical data on chalk samples were gathered by using X-ray fluorescence and instrumental neutron activation. Geochemical data are compared with the well-logging results. Geophysical logging suggests that there is reduced porosity in the Danian reservoir units LDP and UDT in both wells. The chalk drill core samples from the section with reduced porosity also show a lower Ca content. A high Si content is observed in these samples and a number of trace elements in chalk show a similar distribution with depth. Reservoir porosity may be estimated from the Si content of chalk. Chalk permeability may also be elements Al, Fe and Sc show the same trends as that for Si. Diagenetic changes in chalk also include clay minerals. The gas zone in TWB-8 is characterized by low contents of Na and Cl, i.e. lower water saturation is indicated. Low concentrations of rare earths in all chalk samples show a shale-normalized pattern that is characteristic of marine sediments laid down under oxic conditions. Some changes that occur with depth in the Ce anomaly may indicate a slight change in the depositional environment. The content of manganese continuously decreases with depth, from Danian (about 2000 ppm) to Maastrichtian strata (less than 200 ppm). In this respect, no other chemical element in chalk correlates with Mn. There is no indication as to which mineral or mineral phase one is likely to find in the element. (AB) 14 tabs., 49 ills., 147 refs

Low field NMR surface relaxivity studies of chalk and argillaceous sandstones

DEFF Research Database (Denmark)

Katika, Konstantina; Fordsmand, Henrik; Fabricius, Ida Lykke

2017-01-01

the accuracy of predictions of petrophysical properties of various rocks with the use of NMR spectrometry. We perform laboratory transverse relaxation (T2) measurements on water saturated Gorm field chalk, Stevns Klint chalk, Solsort field greensand and Berea sandstone. These rocks are of particular interest...... field chalk and Solsort field greensand have higher ρ at higher Larmor frequency. By contrast, ρ of the purely calcitic Stevns chalk and quartzitic Berea sandstone proved not to be affected by the changes in frequency. T2 distributions at temperatures ranging from 10 °C to 60 °C provided comparison...

Model description of CHERPAC (Chalk River Environmental Research Pathways Analysis Code); results of testing with post-Chernobyl data from Finland

Energy Technology Data Exchange (ETDEWEB)

Peterson, S-R

1994-07-01

CHERPAC (Chalk River Environmental Research Pathways Analysis Code), a time-dependent code for assessing doses from accidental and routine releases of radionuclides, has been under development since 1987. A complete model description is provide here with equations, parameter values, assumptions and information on parameter distributions for uncertainty analysis. Concurrently, CHERPAC has been used to participate in the two internal model validation exercises BIOMOVS (BIOspheric MOdel Validation Study) and VAMP (VAlidation of Assessment Model Predictions, a co-ordinated research program of the International Atomic Energy Agency). CHERPAC has been tested for predictions of concentrations of {sup 137}Cs in foodstuffs, body burden and dose over time using data collected after the Chernobyl accident of 1986 April. CHERPAC`s results for the recent VAMP scenario for southern Finland are particularly accurate and should represent what the code can do under Canadian conditions. CHERPAC`s predictions are compared with the observations from Finland for four and one-half years after the accident as well as with the results of the other participating models from nine countries. (author). 18 refs., 23 figs., 2 appendices.

Model description of CHERPAC (Chalk River Environmental Research Pathways Analysis Code); results of testing with post-Chernobyl data from Finland

International Nuclear Information System (INIS)

Peterson, S-R.

1994-07-01

CHERPAC (Chalk River Environmental Research Pathways Analysis Code), a time-dependent code for assessing doses from accidental and routine releases of radionuclides, has been under development since 1987. A complete model description is provide here with equations, parameter values, assumptions and information on parameter distributions for uncertainty analysis. Concurrently, CHERPAC has been used to participate in the two internal model validation exercises BIOMOVS (BIOspheric MOdel Validation Study) and VAMP (VAlidation of Assessment Model Predictions, a co-ordinated research program of the International Atomic Energy Agency). CHERPAC has been tested for predictions of concentrations of 137 Cs in foodstuffs, body burden and dose over time using data collected after the Chernobyl accident of 1986 April. CHERPAC's results for the recent VAMP scenario for southern Finland are particularly accurate and should represent what the code can do under Canadian conditions. CHERPAC's predictions are compared with the observations from Finland for four and one-half years after the accident as well as with the results of the other participating models from nine countries. (author). 18 refs., 23 figs., 2 appendices

Effect of Fluid Dynamic Viscosity on the Strength of Chalk

DEFF Research Database (Denmark)

Hedegaard, K.; Fabricius, Ida Lykke

The mechanical strength of high porosity and weakly cemented chalk is affected by the fluid in the pores. In this study, the effect of the dynamic viscosity of non-polar fluids has been measured on outcrop chalk from Sigerslev Quarry, Stevns, Denmark. The outcome is that the measured strength...... of the chalk decreases with increasing dynamic viscosity. The proposed qualitative explanation is that pressure difference supports and enhances the generation of microscopic shear and tensile failures....

Influence of effective stress coefficient on mechanical failure of chalk

DEFF Research Database (Denmark)

Alam, Mohammad Monzurul; Fabricius, Ida Lykke; Hjuler, M.L.

2012-01-01

The Effective stress coefficient is a measure of how chalk grains are connected with each other. The stiffness of chalk may decrease if the amount of contact cements between the grains decreases, which may lead to an increase of the effective stress coefficient. We performed CO2 injection in chal...... precise failure strength of chalk during changed stress state and under the influence of chemically reactive fluids during production of hydrocarbon and geological storage CO2....

ZEEP: Canada's first nuclear reactor

Energy Technology Data Exchange (ETDEWEB)

Green, R.E.; Okazaki, A. [retired, Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

2015-09-15

In 1905 Albert Einstein published his historic paper on special relativity, which contained the equation E=mc 2. The significance of this mass-energy relationship became evident with the discovery of nuclear fission in 1939, when it was realized that large amounts of energy would be released in a fission chain reaction. Canadian scientists were involved in this field from the beginning and their efforts resulted in the startup in September 1945 of the ZEEP reactor at Chalk River, the first reactor to go critical outside the USA. In this paper we recall some of the events that led to the construction of ZEEP, and describe the role it played in the development of the Canadian nuclear energy program. (author)

H Canyon Processing In Correlation With FH Analytical Labs

International Nuclear Information System (INIS)

Weinheimer, E.

2012-01-01

Management of radioactive chemical waste can be a complicated business. H Canyon and F/H Analytical Labs are two facilities present at the Savannah River Site in Aiken, SC that are at the forefront. In fact H Canyon is the only large-scale radiochemical processing facility in the United States and this processing is only enhanced by the aid given from F/H Analytical Labs. As H Canyon processes incoming materials, F/H Labs provide support through a variety of chemical analyses. Necessary checks of the chemical makeup, processing, and accountability of the samples taken from H Canyon process tanks are performed at the labs along with further checks on waste leaving the canyon after processing. Used nuclear material taken in by the canyon is actually not waste. Only a small portion of the radioactive material itself is actually consumed in nuclear reactors. As a result various radioactive elements such as Uranium, Plutonium and Neptunium are commonly found in waste and may be useful to recover. Specific processing is needed to allow for separation of these products from the waste. This is H Canyon's specialty. Furthermore, H Canyon has the capacity to initiate the process for weapons-grade nuclear material to be converted into nuclear fuel. This is one of the main campaigns being set up for the fall of 2012. Once usable material is separated and purified of impurities such as fission products, it can be converted to an oxide and ultimately turned into commercial fuel. The processing of weapons-grade material for commercial fuel is important in the necessary disposition of plutonium. Another processing campaign to start in the fall in H Canyon involves the reprocessing of used nuclear fuel for disposal in improved containment units. The importance of this campaign involves the proper disposal of nuclear waste in order to ensure the safety and well-being of future generations and the environment. As processing proceeds in the fall, H Canyon will have a substantial

Temporal variability of micro-organic contaminants in lowland chalk catchments: New insights into contaminant sources and hydrological processes.

Science.gov (United States)

Manamsa, K; Lapworth, D J; Stuart, M E

2016-10-15

This paper explores the temporal variation of a broad suite of micro organic (MO) compounds within hydrologically linked compartments of a lowland Chalk catchment, the most important drinking water aquifer in the UK. It presents an assessment of results from relatively high frequency monitoring at a well-characterised site, including the type and concentrations of compounds detected and how they change under different hydrological conditions including exceptionally high groundwater levels and river flow conditions during 2014 and subsequent recovery. This study shows for the first time that within the Chalk groundwater there can be a greater diversity of the MOs compared to surface waters. Within the Chalk 26 different compounds were detected over the duration of the study compared to 17 in the surface water. Plasticisers (0.06-39μg/L) were found to dominate in the Chalk groundwater on 5 visits (38.4%) accounting for 14.5% of detections but contributing highest concentrations whilst other compounds dominated in the surface water. Trichloroethene and atrazine were among the most frequently detected compounds. The limit for the total pesticide concentration detected did not exceed EU/UK prescribed concentration values for drinking water. Emerging organic compounds such as caffeine, which currently do not have water quality limits, were also detected. The low numbers of compounds found within the hyporheic zone highlight the role of this transient interface in the attenuation and breakdown of the MOs, and provision of an important ecosystem service. Copyright © 2016 British Geological Survey, NERC. Published by Elsevier B.V. All rights reserved.

Early years of nuclear energy research in Canada

International Nuclear Information System (INIS)

Laurence, G.C.

1980-01-01

The first experimental attempts in Canada to obtain energy from uranium fission were carried out by the author in the Ottawa laboratories of the National Research Council from 1940 to 42. This program grew into a joint British-Canadian laboratory in Montreal. Work done at this laboratory, which moved to Chalk River in 1946, led to the construction of ZEEP (the first nuclear reactor to operate outside of the United States) NRX, and ultimately to the development of the CANDU power reactors. People involved in the work and events along the way are covered in detail. (LL)

Return on experience on nuclear accidents

International Nuclear Information System (INIS)

Barre, Bertrand

2015-09-01

After a presentation of the International Nuclear and radiological Events Scale (INES scale), of its levels and criteria, this article proposes brief recalls of some nuclear accidents which occurred in nuclear reactors: Chalk River in Canada (1952), Windscale in England (1957), the universal Canadian reactor (NRU in 1958), the SL1 reactor of the Idaho National Laboratory in the USA (1961), the Swiss Lucens reactor (1969), Saint-Laurent des Eaux in France (1969 and 1980). More detailed descriptions are then given for the Three Mile Island accident in 1979, the Chernobyl accident in 1986, and the Fukushima accident in 2011. The main causes of these accidents are identified: loss of control of chain reaction, cooling defect on a stopped reactor, cooling defect on an operated reactor. Some lessons are drawn from these facts, and some characteristics of the EPR are outlined with respect with problems encountered in these accidents

Uranium traps in the phosphate bearing sudr chalk, in northeastern sinai, Egypt

International Nuclear Information System (INIS)

Hussein, H.A.; El-Aassy, I.E.; Mahdy, M.A.; Dabbour, G.A.; Mansour, M.Gh.; Morsy, A.M.

1998-01-01

The maastrichtian sudr formation in northeastern sinai is composed of three members, the lower chalk, the middle phosphate and chart-bearing and the upper chalk members. Lemon yellow secondary uranium mineralization, distributed in the lower chalk member and in some phosphate beds from the middle phosphate member are observed. The XRD analyses of some samples from the uranium bearing chalk and the phosphate beds showed the presence of the secondary uranium minerals carnotite, bergenite and upalite. The mode of uranium occurrences could be interpreted as a result of the phosphatic beds decomposition and their subjection to later diagenetic processes. Uranium leaching circulation from phosphate rocks led to the liberation of uranium from the phosphates, and vanadium from the bituminous material and clay minerals. These migrated and were deposited locally and within the underlying chalk beds which acted as a lithologic trap

Change of Static and Dynamic Elastic Properties due to CO² Injection in North Sea Chalk

DEFF Research Database (Denmark)

Alam, Mohammad Monzurul; Hjuler, M.L.; Christensen, H.F.

2012-01-01

important in enhanced oil recovery by CO2 injection (CO2-EOR) in chalk as, chalk reservoirs are vulnerable to compaction under changed stress and pore fluid. From South Arne field, North Sea, we used Ekofisk Formation chalk having approximately 20% non-carbonate and Tor Formation chalk having less than 5...

Impact of supercritical CO2 injection on petrophysical and rock mechanics properties of chalk: an experimental study on chalk from South Arne field, North Sea

DEFF Research Database (Denmark)

Alam, Mohammad Monzurul; Hjuler, Morten Leth; Christensen, Helle Foged

2011-01-01

Changes in chalk due to EOR by injecting supercritical CO2 (CO2-EOR) can ideally be predicted by applying geophysical methods designed from laboratory-determined petrophysical and rock mechanics properties. A series of petrophysical and rock mechanics tests were performed on Ekofisk Formation...... and Tor Formation chalk of the South Arne field to reveal the changes in petrophysical and rock mechanics properties of chalk due to the injection of CO2 at supercritical state. An increase in porosity and decrease in specific surface was observed due to injection of supercritical CO2. This indicates...... as indicated by NMR T2 relaxation time was observed. Rock mechanics testing indicates that in 30% porosity chalk from the South Arne field, injection of supercritical CO2 has no significant effect on shear strength and compaction properties, while there is probably a slight decrease in stiffness properties...

Nuclear spectrometry data acquisition system based on LabVIEW

International Nuclear Information System (INIS)

Zhao Dan; Shen Li; Deng Lili; Zhou Sichun

2006-01-01

The whole process of designing nuclear spectrometry data acquisition system was particularized with LabVIEW and data acquisition board, based on virtual instrument technology. It can analyze the output of the radiation detector and give the height spectrum by the method of the continuous real-time data acquisition and the abstraction of pulse signal amplitude. The simple test shows that this system can meet the demand, and it can be easily expanded according to the situation. (authors)

Dissection of genetic architecture of grain chalk using NIR spectroscopy

Science.gov (United States)

Chalk is a major quality characteristic that causes grain breakage during milling and loss of crop value. In this study, we sought to elucidate the quantitatively inherited grain chalk trait in rice and to conduct genome-wide association mapping to identify SNPs and candidate genes associated with ...

New insight into the microtexture of chalks from NMR analysis

DEFF Research Database (Denmark)

Faÿ-Gomord, Ophélie; Soete, Jeroen; Katika, Konstantina

2016-01-01

An integrated petrographical and petrophysical study was carried out on a set of 35 outcrop chalk samples, covering a wide range of lithologies and textures. In this study various chalk rock-types have been characterized, in terms of microtextures and porous network, by integrating both geologica...

Change in Biot's effective stress coefficient of chalk during pore collapse

DEFF Research Database (Denmark)

Alam, M. Monzurul; Fabricius, Ida Lykke

2013-01-01

the grains could also change during elastic deformation of the grains in a rock mechanics test. Diagenetic change in grain contact cement of chalk can be compared with stress-induced change in the laboratory. The change in porosity is studied with reference to the change in effective stress on grain contacts...... and porosity reduces at a slower rate. We noticed that presence of non carbonates and hydrocarbon could increase σ'm. During rock mechanics test in the lab, with increased applied stress, σ'm increases, Biot's effective stress coefficient shows a decreasing trend, while a minor porosity reduction was observed......Biot's effective stress coefficient (α) is a measure of how well grains in the rocks are connected with each other. The amount of contact cements between the grains determines the stiffness of rocks. Change in grain contact occurs during natural diagenesis of sedimentary rock. Contact between...

Water in chalk reservoirs: 'friend or foe?'

International Nuclear Information System (INIS)

Hjuler, Morten Leth

2004-01-01

Most of the petroleum fields in the Norwegian sector of the North Sea are sandstone reservoirs; the oil and gas are trapped in different species of sandstone. But the Ekofisk Field is a chalk reservoir, which really challenges the operator companies. When oil is produced from chalk reservoirs, water usually gets in and the reservoir subsides. The subsidence may be expensive for the oil companies or be used to advantage by increasing the recovery rate. Since 60 per cent of the world's petroleum reserves are located in carbonate reservoirs, it is important to understand what happens as oil and gas are pumped out. Comprehensive studies at the Department of Petroleum Technology and Applied Geophysics at Stavanger University College in Norway show that the mechanical properties of chalk are considerably altered when the pores in the rock become saturated with oil/gas or water under different stress conditions. The processes are extremely complex. The article also maintains that the effects of injecting carbon dioxide from gas power plants into petroleum reservoirs should be carefully studied before this is done extensively

Rock physical aspects of CO{sub 2} injection in chalk

Energy Technology Data Exchange (ETDEWEB)

Alam, M.M.

2011-04-15

Impact of supercritical CO{sub 2} on the petrophysical and rock-mechanics properties of Ekofisk Formation and Tor Formation chalk from South Arne field, Danish North Sea, chalk was investigated. A series of laboratory experiments was performed on core material collected from the reservoir zone of the South Arne field in order to reveal the changes with respect to porosity, specific surface, pore stiffness, wettability, mineralogy and mechanical failure. In addition, a theoretical rock physical background was also established in order to be able to make sensible interpretation of laboratory data. Sound wave velocity was used as the central tool to study any change in petrophysical and rock mechanical properties. The main focus was to achieve a better understanding of effective stress coefficient (also known as Biot's coefficient); by means of which effective stress can be predicted more accurately. Independent theoretical studies were made on diagenesis, surface properties and stiffness of chalk and their relation with sonic velocity (or Biot's coefficient calculated from sonic velocity). The knowledge and experience from these studies was combined to achieve the main research objective of monitoring changes in hydrocarbon reservoirs in chalk due to CO{sub 2} injection. In order to understand the development of chalk from calcareous ooze and achieving pore stiffness, the diagenesis process of a sedimentary sequence from Kerguelen Plateau in the Indian Ocean was studied. The principal objective of the study was to explore how different porosity reduction mechanisms change the strength of these deep sea carbonate-rich sediments and how these mechanisms can be traced from the change in Biot's coefficient, alpha. In calcareous ooze, alpha was found close to one. Mechanical compaction reduces porosity, but only leads to a minor decrease in alpha. Recrystallization process renders particles smoother, but do not lead to reduction in alpha unless it gives

The balanced scorecard advantage: Driving strategic change into Canada's nuclear laboratory site operations

International Nuclear Information System (INIS)

Lafreniere, P.; Weeks, D.

2001-01-01

The challenges presented by the size, diversity, complexity and history of the Facilities and Nuclear Operations (FNO) Group at AECL's Chalk River Laboratories (CRL) required a change to the traditional management approach. As a result, a strategy was adopted that focused on integrating contemporary business practices such as process mapping, activity based management and use of the Balanced Scorecard methodology into the operational culture at CRL. In addition, revitalization of the performance management methods process was undertaken to provide a tool for assessment of business and individual performance. performance. (author)

Childhood leukemia around five nuclear facilities in Canada

International Nuclear Information System (INIS)

Elaguppillai, V.

1992-05-01

As a result of public concern over the incidence of leukemia around the Sellafield nuclear fuel reprocessing plant, the Canadian Atomic Energy Control Board commissioned a study to test for similar clustering around licensed nuclear facilities in Ontario. In this study the incidence and mortality of leukemia among children up to the age of 14 years born within a radius of about 25 km from five different types of facilities were compared to the provincial average. The facilities considered were the Pickering Nuclear Generating Station, the Bruce Nuclear Power Development, the uranium conversion facility at Port Hope, the uranium mine and mill facilities in Elliot Lake, and the Chalk River Laboratories. The ratio of observed to expected childhood leukemias was around unity at the 95 percent confidence level, indicating that the occurrence of the disease is not significantly different from the provincial average. The sample size is not large enough to distinguish between a change occurrence and a true excess or deficit. (table)

Process for treating oil-chalk

Energy Technology Data Exchange (ETDEWEB)

1925-10-20

A process for treating oil-chalk or similar oil-containing minerals is characterized in that the material is treated in a stream of air diluted with indifferent gases at a temperature of about 150/sup 0/ to 160/sup 0/C.

Trace elemental analysis of school chalk using energy dispersive X-ray florescence spectroscopy (ED-XRF)

International Nuclear Information System (INIS)

Maruthi, Y. A.; Das, N. Lakshmana; Ramprasad, S.; Ram, S. S.; Sudarshan, M.

2015-01-01

The present studies focus the quantitative analysis of elements in school chalk to ensure the safety of its use. The elements like Calcium (Ca), Aluminum (Al), Iron (Fe), Silicon (Si) and Chromium (Cr) were analyzed from settled chalk dust samples collected from five classrooms (CD-1) and also from another set of unused chalk samples collected from local market (CD-2) using Energy Dispersive X-Ray florescence(ED-XRF) spectroscopy. Presence of these elements in significant concentrations in school chalk confirmed that, it is an irritant and occupational hazard. It is suggested to use protective equipments like filtered mask for mouth, nose and chalk holders. This study also suggested using the advanced mode of techniques like Digital boards, marker boards and power point presentations to mitigate the occupational hazard for classroom chalk

Trace elemental analysis of school chalk using energy dispersive X-ray florescence spectroscopy (ED-XRF)

Energy Technology Data Exchange (ETDEWEB)

Maruthi, Y. A., E-mail: ymjournal2014@gmail.com [Associate professor, Dept of Environmental Studies, GITAM Institute of Science, GITAM University, Visakhapatnam, A.P (India); Das, N. Lakshmana, E-mail: nldas9@gmail.com [Professor, Dept of Physics, GITAM Institute of Science, GITAM University, Visakhapatnam, A.P (India); Ramprasad, S., E-mail: ramprasadsurakala@gmail.com [Research Scholar, Dept of Environmental science, GITAM Institute of Science, GITAM University, Visakhapatnam, A.P (India); Ram, S. S., E-mail: tracebio@gmail.com [Research Scholar, Dept of Trace element research, UGC-DAE Consortium Centre, Kolkata centre India (India); Sudarshan, M., E-mail: sude@alpha.iuc.res.in [Scientist-F, Dept of Trace element research, UGC-DAE Consortium Centre, Kolkata centre India (India)

2015-08-28

The present studies focus the quantitative analysis of elements in school chalk to ensure the safety of its use. The elements like Calcium (Ca), Aluminum (Al), Iron (Fe), Silicon (Si) and Chromium (Cr) were analyzed from settled chalk dust samples collected from five classrooms (CD-1) and also from another set of unused chalk samples collected from local market (CD-2) using Energy Dispersive X-Ray florescence(ED-XRF) spectroscopy. Presence of these elements in significant concentrations in school chalk confirmed that, it is an irritant and occupational hazard. It is suggested to use protective equipments like filtered mask for mouth, nose and chalk holders. This study also suggested using the advanced mode of techniques like Digital boards, marker boards and power point presentations to mitigate the occupational hazard for classroom chalk.

Nuclear spectrometry signal acquisition and processing system based on LabVIEW and C

International Nuclear Information System (INIS)

Chen Xiaojun; Fang Fang; Chen Mingchi; Jiang Zancheng; Wang Min

2008-01-01

The process of designing nuclear spectrometry signal acquisition and processing system based on virtual instrument technology is showed in this article. For the deficiency of LabVIEW in big data analyzing and processing, a method is presented in which C programmer is inserted and applied in signal smoothing, peak searching and area of the peak calculating. A complete nuclear spectrometry signal acquisition, processing and document management system is implemented. (authors)

The sedimentology of redeposited chalk

DEFF Research Database (Denmark)

Anderskouv, Kresten; Surlyk, Finn; Gale, Andy

Redeposited facies in the Upper Cretaceous Chalk Group constitute major hydrocarbon reservoirs in the North Sea Central Graben. Existing facies models are largely based on publications from the early 1980's dealing with core material from the Norwegian sector. However, the recognition, interpreta...

Twelve tips for the production of digital chalk-talk videos.

Science.gov (United States)

Rana, Jasmine; Besche, Henrike; Cockrill, Barbara

2017-06-01

Increasingly over the past decade, faculty in medical and graduate schools have received requests from digital millennial learners for concise faculty-made educational videos. At our institution, over the past couple of years alone, several hundred educational videos have been created by faculty who teach in a flipped-classroom setting of the pre-clinical medical school curriculum. Despite the appeal and potential learning benefits of digital chalk-talk videos first popularized by Khan Academy, we have observed that the conceptual and technological barriers for creating chalk-talk videos can be high for faculty. To this end, this tips article offers an easy-to-follow 12-step conceptual framework to guide at-home production of chalk-talk educational videos.

Chalk effect on PVC cross-linking under irradiation; Vliyanie mela na sshivanie PVKh pri obluchenii

Energy Technology Data Exchange (ETDEWEB)

Chudinova, V V; Guzeev, V V; Mozzhukhin, V B; Pomerantseva, Eh G; Nozrina, F D; Zhil` tsov, V V; Zubov, V P

1994-12-31

Effect of nonmodified and modified chalk on curing degree of polymer matrix was studied under-irradiation of PVC-compositions. Films of the compositions (100 mass part 7 PVC, 0-100 mas.part of chalk, 2.5 - lead sulfate, 1.5 - lead stearate and 0.3 - glycerin) were irradiated up to absorbed dose 0.1 MGy in an inert medium. Content of gel-fraction after boiling in THF was determined with use of IR spectroscopy. It was established, that intensive dehydrochlorination and polymer curing took place on chalk particle surface. Network fixed strongly chalk particles. However, chalk inhibited processes of dehydrochlorination and PVC curing, increasing amount of noncured PVC in polymer matrix.

Dual hydraulic behaviour of the Chalk in the Netherlands North Sea

NARCIS (Netherlands)

Verweij, H.

2006-01-01

Information on the sedimentary development, seismic stratigraphy and burial compaction of the Chalk Group in the Netherlands North Sea was combined with pressure data and basin modelling to investigate the hydraulic behaviour of the Chalk Group in the Central Graben and Schill Grund High. The

Westinghouse Savannah River Company (WSRC) approach to nuclear facility maintenance

International Nuclear Information System (INIS)

Harrison, D.W.

1991-01-01

The Savannah River Site (SRS) in South Carolina is a 300+ square mile facility owned by the US Department of Energy (DOE) and operated by Westinghouse Savannah River Company (WSRC), the prime contractor; Bechtel Savannah River, Incorporated (BSRI) is a major subcontractor. The site has used all of the five nuclear reactors and it has the necessary nuclear materials processing facilities, as well as waste management and research facilities. The site has produced materials for the US nuclear arsenal and various isotopes for use in space research and nuclear medicine for more than 30 years. In 1989, WSRC took over as prime contractor, replacing E.I. du Pont de Nemours and Company. At this time, a concentrated effort began to more closely align the operating standards of this site with those accepted by the commercial nuclear industry of the United States. Generally, this meant acceptance of standards of the Institute of Nuclear Power Operations (INPO) for nuclear-related facilities at the site. The subject of this paper is maintenance of nuclear facilities and, therefore, excludes discussion of the maintenance of non-nuclear facilities and equipment

Ekofisk chalk: core measurements, stochastic reconstruction, network modeling and simulation

Energy Technology Data Exchange (ETDEWEB)

Talukdar, Saifullah

2002-07-01

This dissertation deals with (1) experimental measurements on petrophysical, reservoir engineering and morphological properties of Ekofisk chalk, (2) numerical simulation of core flood experiments to analyze and improve relative permeability data, (3) stochastic reconstruction of chalk samples from limited morphological information, (4) extraction of pore space parameters from the reconstructed samples, development of network model using pore space information, and computation of petrophysical and reservoir engineering properties from network model, and (5) development of 2D and 3D idealized fractured reservoir models and verification of the applicability of several widely used conventional up scaling techniques in fractured reservoir simulation. Experiments have been conducted on eight Ekofisk chalk samples and porosity, absolute permeability, formation factor, and oil-water relative permeability, capillary pressure and resistivity index are measured at laboratory conditions. Mercury porosimetry data and backscatter scanning electron microscope images have also been acquired for the samples. A numerical simulation technique involving history matching of the production profiles is employed to improve the relative permeability curves and to analyze hysteresis of the Ekofisk chalk samples. The technique was found to be a powerful tool to supplement the uncertainties in experimental measurements. Porosity and correlation statistics obtained from backscatter scanning electron microscope images are used to reconstruct microstructures of chalk and particulate media. The reconstruction technique involves a simulated annealing algorithm, which can be constrained by an arbitrary number of morphological parameters. This flexibility of the algorithm is exploited to successfully reconstruct particulate media and chalk samples using more than one correlation functions. A technique based on conditional simulated annealing has been introduced for exact reproduction of vuggy

The effect of chalk on the finger-hold friction coefficient in rock climbing.

Science.gov (United States)

Amca, Arif Mithat; Vigouroux, Laurent; Aritan, Serdar; Berton, Eric

2012-11-01

The main purpose of this study was to examine the effect of chalk on the friction coefficient between climber's fingers and two different rock types (sandstone and limestone). The secondary purpose was to investigate the effects of humidity and temperature on the friction coefficient and on the influence of chalk. Eleven experienced climbers took part in this study and 42 test sessions were performed. Participants hung from holds which were fixed on a specially designed hang board. The inclination of the hang board was progressively increased until the climber's hand slipped from the holds. The angle of the hang board was simultaneously recorded by using a gyroscopic sensor and the friction coefficient was calculated at the moment of slip. The results showed that there was a significant positive effect of chalk on the coefficient of friction (+18.7% on limestone and +21.6% on sandstone). Moreover sandstone had a higher coefficient of friction than limestone (+15.6% without chalk, +18.4% with chalk). These results confirmed climbers' belief that chalk enhances friction. However, no correlation with humidity/temperature and friction coefficient was noted which suggested that additional parameters should be considered in order to understand the effects of climate on finger friction in rock climbing.

Advanced waterflooding in chalk reservoirs: Understanding of underlying mechanisms

DEFF Research Database (Denmark)

Zahid, Adeel; Sandersen, Sara Bülow; Stenby, Erling Halfdan

2011-01-01

Over the last decade, a number of studies have shown SO42−, Ca2+ and Mg2+ to be potential determining ions, which may be added to the injected brine for improving oil recovery during waterflooding in chalk reservoirs. However the understanding of the mechanism leading to an increase in oil recove...... of a microemulsion phase could be the possible reasons for the observed increase in oil recovery with sulfate ions at high temperature in chalk reservoirs besides the mechanism of the rock wettability alteration, which has been reported in most previous studies.......Over the last decade, a number of studies have shown SO42−, Ca2+ and Mg2+ to be potential determining ions, which may be added to the injected brine for improving oil recovery during waterflooding in chalk reservoirs. However the understanding of the mechanism leading to an increase in oil recovery...

Proceedings of the international conference on CANDU fuel

International Nuclear Information System (INIS)

Hastings, I.J.

1986-01-01

These proceedings contain full texts of all paper presented at the first International Conference on CANDU Fuel. The Conference was organized and hosted by the Chalk River Branch of the Canadian Nuclear Society and utilized Atomic Energy of Canada Limited's facilities at Chalk River Nuclear Laboratories. Previously, informal Fuel Information Meetings were used in Canada to allow the exchange of information and technology associated with CANDU. The Chalk River conference was the first open international forum devoted solely to CANDU and included representatives of overseas countries with current or potential CANDU programs, as well as Canadian participants. The keynote presentation was given by Dr. J.B. Slater, who noted the correlation between past successes in CANDU fuel cycle technology and the co-operation between researchers, fabricators and reactor owner/operators in all phases of the fuel cycle, and outlined the challenges facing the industry today. In the banquet address, Dr. R.E. Green described the newly restructured AECL Research Company and its mission which blends traditional R and D with commercial initiatives. Since this forum for fuel technology has proven to be valuable, a second International CANDU Fuel Conference is planned for the fall of 1989, again sponsored by the Canadian Nuclear Society

TASCC newsletter volume 8 no. 5

Energy Technology Data Exchange (ETDEWEB)

Thomson, L

1994-05-01

A newsletter produced by Chalk River`s Tandem Accelerator Superconducting Cyclotron Facility. Included in this May issue of TASCC is an update of the facility, a visit by the Nuclear Physics Technical Review Committee, sizing of meteors, Deep River Science Academy on TASCC projects and a listing of May`s experiments. 2 figs.

Persistent and emerging micro-organic contaminants in Chalk groundwater of England and France

International Nuclear Information System (INIS)

Lapworth, D.J.; Baran, N.; Stuart, M.E.; Manamsa, K.; Talbot, J.

2015-01-01

The Chalk aquifer of Northern Europe is an internationally important source of drinking water and sustains baseflow for surface water ecosystems. The areal distribution of microorganic (MO) contaminants, particularly non-regulated emerging MOs, in this aquifer is poorly understood. This study presents results from a reconnaissance survey of MOs in Chalk groundwater, including pharmaceuticals, personal care products and pesticides and their transformation products, conducted across the major Chalk aquifers of England and France. Data from a total of 345 sites collected during 2011 were included in this study to provide a representative baseline assessment of MO occurrence in groundwater. A suite of 42 MOs were analysed for at each site including industrial compounds (n = 16), pesticides (n = 14) and pharmaceuticals, personal care and lifestyle products (n = 12). Occurrence data is evaluated in relation to land use, aquifer exposure, well depth and depth to groundwater to provide an understanding of vulnerable groundwater settings. - Highlights: • Broad range of microorganics detected in Chalk groundwater in England and France. • Plasticisers, pesticides, BPA and THM detected at the highest concentrations. • Pesticides higher in outcrop Chalk, caffeine and BPA at concealed sites. • Occurrences show some relationship to land use, borehole depth and water level. - Broad screening reveals for the first time the extent of emerging microorganic pollution in Chalk groundwater sources across England and France

Dynamic simulation of a two-phase control absorber for neutron flux regulation in a nuclear reactor

International Nuclear Information System (INIS)

Plourde, J.A.; Lepp, R.M.

1979-08-01

A dynamic simulation of the two-phase control absorber being proposed for future Canadian nuclear power reactors has been developed at Chalk River Nuclear Laboratories. The model, implemented on a hybrid computer, was developed to study absorber dynamics at different circuit operating conditions and with different circuit configurations. The simulation is modular, with as much correspondence as possible between individual modules and the physical entities. The dynamics of several of the modules are described by partial differential equations, with space and time as independent variables. These are solved via the Continuous Space/Discrete Time technique. The simulation has been validated with data from the Two-Phase Absorber Experimental (TOPAX) Rig installed at the ZED-2 test reactor. (author)

Nuclear industry prospects: A Canadian perspective

International Nuclear Information System (INIS)

Morden, Reid

1995-01-01

Canada, with its proven, safe and versatile CANDU reactor is well poised for the second half-century of nuclear fission. Canada's nuclear pedigree goes back to the turn-of-the-century work of Ernest Rutherford in Montreal. This year, Canada's nuclear industry celebrates the 50th anniversary of the start-up of its first research reactor at Chalk River. Last year, the pioneering work of Bert ram Blockhouse in Physics was honoured with a Nobel Prize. Future international success for the nuclear industry, such as has been achieved here in Korea, depends on continued cooperative and collaborative team work between the public and private sectors, continued strong research and development backing by the government, and new strategic partnerships. The biggest challenge is financing for the emerging markets. The brightness or dimness of future prospects are relative to the intensity of the lessons learned from history. In Canada we have a fairly long nuclear pedigree, It goes back almost a century to 1898, when Ernest Rutherford set up a world centre at McGill University in Montreal for research into the structure of the atom and into radioactivity

Dynamic and static elastic moduli of North Sea and deep sea chalk

DEFF Research Database (Denmark)

Gommesen, Lars; Fabricius, Ida Lykke

2001-01-01

We have established an empirical relationship between the dynamic and the static mechanical properties of North Sea and deep sea chalk for a large porosity interval with respect to porosity, effective stress history and textural composition. The chalk investigated is from the Tor and Hod Formatio...

Progress report physics division, 1983 July 1 - December 31

International Nuclear Information System (INIS)

1984-02-01

This report summarizes work carried out during the last half of 1983 in the Physics Division of the Chalk River Nuclear Laboratories in the areas of superconducting cyclotron facility development, nuclear physics research, applied physics, solid state physics, and applied mathematics and computation

Savannah River Site nuclear materials management plan FY 2017-2031

Energy Technology Data Exchange (ETDEWEB)

Magoulas, V. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-06-22

The purpose of the Nuclear Materials Management Plan (herein referred to as “this Plan”) is to integrate and document the activities required to disposition the legacy and/or surplus Enriched Uranium (EU) and Plutonium (Pu) and other nuclear materials already stored or anticipated to be received by facilities at the Department of Energy (DOE) Savannah River Site (SRS) as well as the activities to support the DOE Tritium mission. It establishes a planning basis for EU and Pu processing operations in Environmental Management Operations (EMO) facilities through the end of their program missions and for the tritium through the National Nuclear Security Administration (NNSA) Defense Programs (DP) facilities. Its development is a joint effort among the Department of Energy - Savannah River (DOE-SR), DOE – Environmental Management (EM), NNSA Office of Material Management and Minimization (M3), NNSA Savannah River Field Office (SRFO), and the Management and Operations (M&O) contractor, Savannah River Nuclear Solutions, LLC (SRNS). Life-cycle program planning for Nuclear Materials Stabilization and Disposition and the Tritium Enterprise may use this Plan as a basis for the development of the nuclear materials disposition scope and schedule. This Plan assumes full funding to accomplish the required project and operations activities. It is recognized that some aspects of this Plan are pre decisional with regard to National Environmental Policy Act (NEPA); in such cases new NEPA actions will be required.

Probing the intrinsically oil-wet surfaces of pores in North Sea chalk at subpore resolution

DEFF Research Database (Denmark)

Hassenkam, Tue; Skovbjerg, Lone Lindbæk; Stipp, Susan Louise Svane

2009-01-01

been drilled in a water-bearing formation. At this site, the chalk has never seen oil, though at other locations, the same stratigraphic horizon with the same rock properties is known to be a productive oil reservoir. Thus the properties of the investigated particle surfaces are inherent to the chalk......Ultimate Oil recovery from chalk reservoirs is limited by many factors - including the grain size and the surface properties of the small mainly biogenic calcite particles that chalk is made off . Wettability, the tendency for water or oil to spread over a surface, of the particle surfaces is one...... of the controlling factors for the effectiveness of water flooding, one of the most common methods to improve oil recovery in Chalk reservoirs. Understanding surface wetting and its variability at scales smaller than the pore dimension will potentially provide clues for more effective oil production methods. We used...

Improved Oil Recovery in Chalk. Spontaneous Imbibition affected by Wettability, Rock Framework and Interfacial Tension

Energy Technology Data Exchange (ETDEWEB)

Milter, J.

1996-12-31

The author of this doctoral thesis aims to improve the oil recovery from fractured chalk reservoirs, i.e., maximize the area of swept zones and their displacement efficiencies. In order to identify an improved oil recovery method in chalk, it is necessary to study wettability of calcium carbonate and spontaneous imbibition potential. The thesis contains an investigation of thin films and wettability of single calcite surfaces. The results of thin film experiments are used to evaluate spontaneous imbibition experiments in different chalk types. The chalk types were described detailed enough to permit considering the influence of texture, pore size and pore throat size distributions, pore geometry, and surface roughness on wettability and spontaneous imbibition. Finally, impacts of interfacial tension by adding anionic and cationic surfactants to the imbibing water phase are studied at different wettabilities of a well known chalk material. 232 refs., 97 figs., 13 tabs.

Reactive transport modelling of groundwater chemistry in a chalk aquifer at the watershed scale.

Science.gov (United States)

Mangeret, A; De Windt, L; Crançon, P

2012-09-01

This study investigates thermodynamics and kinetics of water-rock interactions in a carbonate aquifer at the watershed scale. A reactive transport model is applied to the unconfined chalk aquifer of the Champagne Mounts (France), by considering both the chalk matrix and the interconnected fracture network. Major element concentrations and main chemical parameters calculated in groundwater and their evolution along flow lines are in fair agreement with field data. A relative homogeneity of the aquifer baseline chemistry is rapidly reached in terms of pH, alkalinity and Ca concentration since calcite equilibrium is achieved over the first metres of the vadose zone. However, incongruent chalk dissolution slowly releases Ba, Mg and Sr in groundwater. Introducing dilution effect by rainwater infiltration and a local occurrence of dolomite improves the agreement between modelling and field data. The dissolution of illite and opal-CT, controlling K and SiO(2) concentrations in the model, can be approximately tackled by classical kinetic rate laws, but not the incongruent chalk dissolution. An apparent kinetic rate has therefore been fitted on field data by inverse modelling: 1.5×10(-5) mol(chalk)L (-1) water year (-1). Sensitivity analysis indicates that the CO(2) partial pressure of the unsaturated zone is a critical parameter for modelling the baseline chemistry over the whole chalk aquifer. Copyright © 2012 Elsevier B.V. All rights reserved.

The surface reactivity of chalk (biogenic calcite) with hydrophilic and hydrophobic functional groups

Science.gov (United States)

Okhrimenko, D. V.; Dalby, K. N.; Skovbjerg, L. L.; Bovet, N.; Christensen, J. H.; Stipp, S. L. S.

2014-03-01

The surface properties of calcium carbonate minerals play an important role in a number of industrial and biological processes. Properties such as wettability and adsorption control liquid-solid interface behaviour and thus have a strong influence on processes such as biomineralisation, remediation of aquifers and oil recovery. We investigated how two model molecules of different polarity, namely water and ethanol, interact with reservoir and outcrop chalk samples and we compared their behaviour with that of pure, inorganically precipitated calcite. Thermodynamic quantities, such as the work of wetting, surface energy and isosteric adsorption enthalpy, were determined from vapour adsorption isotherms. The chalks were studied fresh and after extraction of organic residues that were originally present in these samples. The work of wetting correlates with the amount of organic matter present in the chalk samples but we observed a fundamental difference between the adsorption properties of chalk and pure, inorganically precipitated calcite toward the less polar, ethanol molecule. Further analysis of the chemical composition of the organic matter extracted from the chalk samples was made by gas chromatography (GC-MS). Monitoring surface composition by X-ray photoelectron spectroscopy (XPS) before and after extraction of the organic material, and with atomic force microscopy (AFM), showed that nanometer sized clay crystals observed on the chalk particle surfaces could be an important part of the reason for the differences. Removal of the extractable portion of the hydrocarbons liberates adsorption sites that have different wetting properties than the rest of the chalk and these have an energy distribution that is similar to clays. Thus, the results exemplify the complexity of biogenic calcite adsorption behaviour and demonstrate that chalk wetting in drinking water aquifers as well as oil reservoirs is controlled partly by the nanoparticles of clay that have grown on the

Seminar for labour on the objectives and work of CRNL May 29, 30, 31, 1972

International Nuclear Information System (INIS)

1972-01-01

The Seminar for Labour on the Objectives and Work of CRNL was held in Chalk River, Ontario, Canada on May 29-31, 1972. The main objective is to review the work and contributions of employees at Chalk River Nuclear Laboratories. Three specific matters communicated at the conference are: a full sense of pride in the achievements the employees have helped to bring about; a realization that CRNL has a long future ahead of it and though much as been accomplished, much more remains to be done; and, that Chalk River is a good place to work and there is a high regard for the safety of every employee. Not all aspects of work done at CRNL could be presented, however the selected samples cover a fairly large spectrum of the functions in the Laboratories. This document provides the opportunity to determine just how large and essential a role the employees and the Laboratory has played and will continue to play in Canadian and world wide affairs.

Biot Critical Frequency Applied to Description of Failure and Yield of Highly Porous Chalk with Different Pore Fluids

DEFF Research Database (Denmark)

Andreassen, Katrine Alling; Fabricius, Ida Lykke

2010-01-01

Injection of water into chalk hydrocarbon reservoirs has led to mechanical yield and failure. Laboratory experiments on chalk samples correspondingly show that the mechanical properties of porous chalk depend on pore fluid and temperature. In case of water-saturated samples, the concentration...... is controlled by solid-fluid friction. The reference frequency is thus a measure of this friction, and we propose that the fluid effect on mechanical properties of chalk may be the result of liquid-solid friction. We reviewed 622 published experiments on mechanical properties of porous chalk. The data include...... chalk samples that were tested at temperatures from 20 °C to 130 °C with the following pore fluids: fresh water, synthetic seawater, glycol, and oil of varying viscosity. The critical frequency is calculated for each experiment. For each specimen, we calculate the thickness to the slipping plane outside...

Progress report: Physical Sciences - TASCC Division, 1992 July 01 -December 31

Energy Technology Data Exchange (ETDEWEB)

Hardy, J C [ed.

1993-05-01

This report summarizes operations and research activities in the Nuclear Physics Branch and the TASCC Accelerators and Development Branch at Chalk River Laboratories during the last half of 1992. 27 figs., 10 tabs.

Progress report: Physical Sciences - TASCC Division, 1992 July 01 -December 31

International Nuclear Information System (INIS)

Hardy, J.C.

1993-05-01

This report summarizes operations and research activities in the Nuclear Physics Branch and the TASCC Accelerators and Development Branch at Chalk River Laboratories during the last half of 1992. 27 figs., 10 tabs

TASCC newsletter volume 8 no. 5

International Nuclear Information System (INIS)

Thomson, L.

1994-05-01

A newsletter produced by Chalk River's Tandem Accelerator Superconducting Cyclotron Facility. Included in this May issue of TASCC is an update of the facility, a visit by the Nuclear Physics Technical Review Committee, sizing of meteors, Deep River Science Academy on TASCC projects and a listing of May's experiments. 2 figs

Combining Chalk Talk with PowerPoint to Increase In-class Student Engagement

Directory of Open Access Journals (Sweden)

Swati Betharia

2016-11-01

Full Text Available In striving to attain a higher degree of in-class student engagement, and target a larger number of preferred student-learning styles, this case study describes a multimodal teaching approach. PowerPoint slides have gradually gained popularity over the more traditional chalk and talk lecture design. The student population in today’s age seeks more non-passive modes of information delivery. Numerous novel approaches to enhance active learning, such as flipped classroom and problem-based learning, have recently been explored. While working well for therapeutic and lab-based courses, these formats may not be best-suited for all basic science topics. The importance of basic science in a pharmacy curriculum is well emphasized in the 2016 ACPE Standards. To actively involve students in a pharmacology lecture on diuretics, a session was designed to combine the PowerPoint and chalk talk approaches. Students created 10 concept diagrams following an instructor, who explained each step in the process using a document camera. For visual learners, these diagrams provided a layered representation of the information, gradually increasing in complexity. For learners with a preference for the reading learning style, the information was also available in corresponding PowerPoint slides. Scores from pre- and post-session quizzes indicated a high level of concept understanding and recall (median 1 [IQR 0 – 2] vs 4 [IQR 3 – 5]; p<0.001. The student perception survey data reported higher in-class attention levels (76%, an appreciation for the utility of self-created concept diagrams (88%, and a call for additional sessions being presented in this format (73%. Targeting a variety of student learning styles by using the active development of concept diagrams, in addition to traditional PowerPoint slides, can promote student engagement and enhance content understanding.   Type: Case Study

THE STUDY OF TECHNOLOGICAL PROPERTIES OF PLASTISOLS BASED EMULSION PVC FILLED WITH CHALK GIDROFOBIZIROVANNYM

Directory of Open Access Journals (Sweden)

V. A. Sedykh

2014-01-01

Full Text Available Baby toys are made using the centrifugal molding plastisol based emulsion of polyvinyl chloride plasticized with dioctylphthalate. To reduce cost and decrease biotelemetry the dioctylphthalate on the surface of the product domestic toys than toys produced in China, there was a necessity of introduction of the filler is chalk from different manufacturers. By using a Brookfield vis-cometer PV-D was studied rheology of filled hydrophobized chalk PVC plastisols in storage conditions for up to 72 hours at temperatures of 14-20°C. It was found that the flow plastisols consistent with pseudo-plastic fluids. Given the flow rates of emulsion PVC plastisols filled to 35 % of the mass. hydrophobized chalk. The influence of the content of the plasticizer dioctylphthalate in a narrow interval (37,0 - 41,4 % of the mass. on the viscosity of polymer pastes and the kinetics of its changes during storage. Revealed a linear dependence of the viscosity of the filled hydrophobized chalk plastisols on the speed of rotation of the spindle of the viscometer and during storage. Given the rate of expansion changes the viscosity of the plastisols of the speed of rotation of the spindle of the viscometer, the rate of change in viscosity and calculation of the initial viscosity. Determined the stability of the dispersion hydrophobized chalk in a colloidal solution of PVC in dioctylphthalate during storage. We determined the variation of the content of chalk (ash with top and bottom layers plastisols height 8 cm after 24 hours storage. It is proved that the temperature of the preparation and storage of polymer pastes were determining factors in the regulation of such technological properties of PVC plastisols in the presence hydrophobized chalkas viscosity, stability of the dispersion of chalk and, consequently, the efficiency of distribution plastisols in the form of a centrifugal molding.

From ooze to sedimentary rock, the first diagenetic processes affecting the chalk of eastern Denmark

DEFF Research Database (Denmark)

Moreau, Julien; Boussaha, Myriam; Nielsen, Lars

processes operating in the chalk sediments at widely different scales into a single diagenetic model: At Stevns the chalk is affected by an extensive polygonal fault system which is expressed in onshore and offshore seismic profiles. Smaller scale contractional features like deformation bands (hairline...... strongly affect reservoir properties of the chalk both by establishing compartments and vertical connections. A better understanding of these reservoir modifications will be critical for improving the predictive capability of models describing the behaviour of drinking water and hydrocarbons hosted...

Caoxite-hydroxyapatite composition as consolidating material for the chalk stone from Basarabi-Murfatlar churches ensemble

Science.gov (United States)

Ion, Rodica-Mariana; Turcanu-Caruţiu, Daniela; Fierăscu, Radu-Claudiu; Fierăscu, Irina; Bunghez, Ioana-Raluca; Ion, Mihaela-Lucia; Teodorescu, Sofia; Vasilievici, Gabriel; Rădiţoiu, Valentin

2015-12-01

The development of new composition for surface conservation of some architectural monuments represents now an important research topic. The Basarabi-Murfatlar Ensemble, recognized as the first religious monument from mediaeval Dobrogea (Romania) (from 9th to 11th century), is one of the most impressive archaeological sites of Europe. This ensemble is built from amorphous calcium carbonate, very sensitive to humidity, frost, salts, etc. The aim of this paper is to test on chalk stone samples a new consolidant - hydroxyapatite (HAp) mixed with calcium oxalate trihydrate (caoxite) (COT). Some specific techniques for evaluation its impact on chalk stone surface are used, as follows: petrographical and physical-chemical techniques: SEM, OM, ICP-AES, TGA, FTIR and Raman spectroscopy, chromatic parameters changes, the accelerated weathering tests: heating, freeze-thaw, and their effects on porosity and capillary water uptake by the chalk surface. All these have been evaluated before and after treatment with COT-HAp, putting into evidence the effect of the new composition on the chalk stone surface. HAp induces COT stabilization, and their joint composition can bind weathered stone blocks providing a substantial reinforcement of chalk surface.

Nuclear engineering R ampersand D at the Savannah River Site

International Nuclear Information System (INIS)

Strosnider, D.R.; Ferrara, W.R.

1991-01-01

The Westinghouse Savannah River Company (WSRC) is the prime operating contractor for the US Department of Energy at the Savannah River Site (SRS), located near Aiken, South Carolina. One division of WSRC, the Savannah River Laboratory (SRL), has the primary responsibility for research and development, which includes supporting the safe and efficient operation of the SRS production reactors. Several Sections of SRL, as well as other organization in WSRC, pursue R ampersand D and oversight activities related to nuclear engineering. The Sections listed below are described in more detail in this document: (SRL) nuclear reactor technology and scientific computations department; (SRL) safety analysis and risk management department; (WSRC) new production reactor program; and (WSRC) environment, safety, health, and quality assurance division

Potential for isoproturon, atrazine and mecoprop to be degraded within a chalk aquifer system

Science.gov (United States)

Johnson, Andrew C.; White, Craig; Lal Bhardwaj, C.

2000-06-01

The potential for herbicide degradation in an unconfined chalk aquifer was examined by collecting and spiking fresh samples and incubating them in the laboratory. The microcosms were incubated at 20°C under aerobic conditions and spiked with either isoproturon, atrazine or mecoprop at a concentration of 100 μg/l. The samples were obtained from a single fieldsite within the Upper Chalk aquifer in Hampshire, UK. Groundwater samples required the presence of sterile chalk in a ratio of at least 1:13 to promote isoproturon degradation. An isoproturon degradation potential existed in the soil, and the chalk unsaturated and saturated zones. However, no degradation of isoproturon in the unsaturated zone was observed when a more appropriate simulation of in-situ moisture conditions was carried out. Apart from the soil, no potential for atrazine or mecoprop degradation could be detected in the same samples over a 200-day incubation. In a series of groundwater samples taken from different boreholes, 10-300 m apart, large differences in isoproturon degradation potential were observed. Removal rates for 100 μg/l isoproturon varied from 83-425 ng/day, but in some samples no degradation potential could be detected. The primary metabolite which could be distinguished from isoproturon degradation in chalk and groundwater was monodesmethyl-isoproturon. When a chalk groundwater sample was spiked with isoproturon at 0.9 μg/l, this was not degraded over a 300-day incubation period. Further experiments with fresh groundwater from a Triassic Sandstone site illustrated that groundwater bacteria could degrade isoproturon at the more realistic temperature of 10°C as well as at 20°C.

Risk assessment for nuclear processes at the Savannah River Site

International Nuclear Information System (INIS)

Durant, W.S.

1992-01-01

The Savannah River Site, one of the US Department of Energy's nuclear materials processing facilities, has for many years conducted risk-based safety analyses for the nuclear processes conducted at the facilities. This approach has allowed comparisons of risks to established criteria for acceptability. When the risk-based program was begun, it was evident that its success would depend upon having a compilation of data that was site specific. The decision was made to create a data bank of undesirable events that had occurred at the site's nuclear fuel reprocessing facilities. From this modest beginning, five data banks have been created for nuclear fuel reprocessing, waste management, nuclear fuel fabrication, tritium operations, and the Savannah River Technology Center. In addition to the primary purpose of providing a sound basis for risk-based safety analyses, these highly versatile data banks are routinely used for equipment breakdown histories, incident investigations, design studies, project justifications, reliability studies, process problem solving, training, and audits

Porosity and sonic velocity depth trends of Eocene chalk in Atlantic Ocean: Influence of effective stress and temperature

DEFF Research Database (Denmark)

Awedalkarim, Ahmed; Fabricius, Ida Lykke

2014-01-01

We aimed to relate changes in porosity and sonic velocity data, measured on water-saturated Eocene chalks from 36 Ocean Drilling Program drill sites in the Atlantic Ocean, to vertical effective stress and thermal maturity. We considered only chalk of Eocene age to avoid possible influence...... not show or at least it is difficult to define a clear pore-stiffening contact cementation trend as the Ontong Java Plateau chalk. Mechanical compaction is the principal cause of porosity reduction (at shallow depths) in the studied Eocene chalk, at least down to about 5MPa Terzaghi׳s effective stress...

The End of "Chalk and Talk"

Science.gov (United States)

Barlow, Tim

2012-01-01

"Chalk and talk" had been the staple pedagogical approach of my Science teaching practice since entering the profession. I felt that there was a great deal of information that I must impart to my students. My tried and tested way to deliver information to my students had always been simply to stand in front of them and tell it to them... So what…

Spatial analysis of Carbon-14 dynamics in a wetland ecosystem (Duke Swamp, Chalk River Laboratories, Canada)

International Nuclear Information System (INIS)

Yankovich, T.L.; King-Sharp, K.J.; Carr, J.; Robertson, E.; Killey, R.W.D.; Beresford, N.A.; Wood, M.D.

2014-01-01

A detailed survey was conducted to quantify the spatial distribution of 14 C in Sphagnum moss and underlying soil collected in Duke Swamp. This wetland environment receives 14 C via groundwater pathways from a historic radioactive Waste Management Area (WMA) on Atomic Energy Canada Limited (AECL)'s Chalk River Laboratories (CRL) site. Trends in 14 C specific activities were evaluated with distance from the sampling location with the maximum 14 C specific activity (DSS-35), which was situated adjacent to the WMA and close to an area of groundwater discharge. Based on a spatial evaluation of the data, an east-to-west 14 C gradient was found, due to the influence of the WMA on 14 C specific activities in the swamp. In addition, it was possible to identify two groups of sites, each showing significant exponential declines with distance from the groundwater source area. One of the groups showed relatively more elevated 14 C specific activities at a given distance from source, likely due to their proximity to the WMA, the location of the sub-surface plume originating from the WMA, the presence of marsh and swamp habitat types, which facilitated 14 C transport to the atmosphere, and possibly, 14 C air dispersion patterns along the eastern edge of the swamp. The other group, which had lower 14 C specific activities at a given distance from the groundwater source area, included locations that were more distant from the WMA and the sub-surface plume, and contained fen habitat, which is known to act as barrier to groundwater flow. The findings suggest that proximity to source, groundwater flow patterns and habitat physical characteristics can play an important role in the dynamics of 14 C being carried by discharging groundwater into terrestrial and wetland environments. - Highlights: • Groundwater represents an important source of volatile radionuclides to wetlands. • Habitat type influenced 14 C transport from sub-surface to surface environments. • C-14 specific

The Effect of Bacteria Penetration on Chalk Permeability

DEFF Research Database (Denmark)

Halim, Amalia Yunita; Shapiro, Alexander; Nielsen, Sidsel Marie

number of B. licheniformis was detected on the effluent compared with P. putida. However, in the experiment with B. licheniformis mainly spores were detected in the effluent. The core permeability decreased rapidly during injection of bacteria and a starvation period of 12 days did not allow......Bacteria selective plugging is one of the mechanisms through which microorganisms can be applied for enhanced oil recovery. Bacteria can plug the water-bearing zones of a reservoir, thus altering the flow paths and improving sweep efficiency. It is known that the bacteria can penetrate deeply...... into reservoirs, however, a complete understanding of the penetration behavior of bacteria is lacking, especially in chalk formations where the pore throat sizes are almost comparable with the sizes of bacteria vegetative cells. This study investigates the penetration of bacteria into chalk. Two bacteria types...

The leaching of radioactivity from highly radioactive glass blocks buried below the water table: fifteen years of results

International Nuclear Information System (INIS)

Merritt, W.F.

1976-03-01

The results from two test burials of high-level fission products incorporated into nepheline syenite glass indicate that the nuclear wastes from fuel processing for a 30,000 MWe nuclear power industry could be incorporated into such glass and stored beneath the water table in the waste management area of Chalk River Nuclear Laboratories (CRNL) without harm to the environment. (author)

Analysis of fine-dispersed chalk usage as mineral additive in the composition of sand aggrerate concrete

Directory of Open Access Journals (Sweden)

Светлана Николаевна Чепурная

2016-12-01

Full Text Available The research results of fine-disperse chalk addition on physical and mechanical properties of the cement stone and concrete are shown. It is determined that fine-disperse chalk addition in the binder composition increases the content of ultrafine particles. The chalk particles fill the pore space between the cement particles, increasing the packing density, which leads to a density increase, which consequently leads to improved physical and mechanical properties of the concrete: water tightness, cold resistance, corrosion resistance, crack resistance and other properties

Permeability, porosity, dispersion-, diffusion-, and sorption characteristics of chalk samples from Erslev, Mors, Denmark

International Nuclear Information System (INIS)

Carlsen, L.; Batsberg, W.; Skytte Jensen, B.; Bo, P.

1981-08-01

A series of chalk samples from the cretaceous formation overlying the Erslev salt dome have been studied in order to establish permeabilities, porosities, dispersion-, diffusion-, and sorption characteristics of the chalk, Predominantly the investigations have been carried out by application of a liquid chromatographic technique. The chalk was found to be porous (epsilon approximately 0.4), however, of rather low permeability (k approximately 10 -7 cm/sec). It was found that the material exhibits a retarding effect on the migration of cationic species as Cs + , Sr 2+ , Co 2+ , and Eu 3+ , whereas anionic species as Cl - and TcO - 4 move with the water front. The geochemical implications are discussed. (author)

Canadian development program for off-gas management in nuclear facilities

International Nuclear Information System (INIS)

Sridhar, T.S.

1983-01-01

The Canadian program for the development and evaluation of processes and technology for the separation and containment of radioactive species in off-gases is directed towards the following specific aspects: 1) assessment of available treatment technology and evaluation of future clean-up requirements; 2) development and engineering evaluation, under realistic conditions, of promising new processes that would be inherently simpler and safer; and 3) specification of off-gas emission control systems for future nuclear facilities based on the most favourable technology. The program is being carried out by Atomic Energy of Canada Limited in collaboration with the electrical utility, Ontario Hydro, and selected Canadian universities. A brief description is presented of methods for removing tritium and carbon-14 from the moderator systems of CANDU power reactors, methods for removing iodine from the off-gases of a molybdenum-99 production facility at the Chalk River Nuclear Laboratories, and procedures for monitoring the off-gas effluent composition in the Thorium Fuel Reprocessing Experiment (TFRE) facility at the Whiteshell Nuclear Research Establishment

Biot Critical Frequency Applied as Common Friction Factor for Chalk with Different Pore Fluids and Temperatures

DEFF Research Database (Denmark)

Andreassen, Katrine Alling; Fabricius, Ida Lykke

2010-01-01

Injection of water into chalk hydrocarbon reservoirs has lead to mechanical yield and failure. Laboratory experiments on chalk samples correspondingly show that the mechanical properties of porous chalk depend on pore fluid and temperature. Water has a significant softening effect on elastic...... and we propose that the fluid effect on mechanical properties of highly porous chalk may be the result of liquid‐solid friction. Applying a different strain or stress rate is influencing the rock strength and needs to be included. The resulting function is shown to relate to the material dependent...... and rate independent b-factor used when describing the time dependent mechanical properties of soft rock or soils. As a consequence it is then possible to further characterize the material constant from the porosity and permeability of the rock as well as from pore fluid density and viscosity which...

Progress report - Physical and Environmental Sciences - TASCC Division -1995 January 1 to June 30

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-08-01

Included in this progress report of the TASCC division at Chalk River Nuclear Laboratories is the research and development being carried out at this time and a listing of the relevant publications, reports. lectures and conference contributions. 15 tabs. 19 figs.

Progress report, Physics Division, April 1 to June 30, 1975

International Nuclear Information System (INIS)

1975-08-01

The operation and research purposes of the Chalk River MP tandem accelerator are described. Besides programs in nuclear and solid state physics, research is carried out on improved radiation detectors and mathematical support of on-going programs. (E.C.B.)

Progress report - Physical and Environmental Sciences - TASCC Division -1995 January 1 to June 30

International Nuclear Information System (INIS)

1995-08-01

Included in this progress report of the TASCC division at Chalk River Nuclear Laboratories is the research and development being carried out at this time and a listing of the relevant publications, reports. lectures and conference contributions. 15 tabs. 19 figs

Development of aluminosilicate and borosilicate glasses as matrices for CANDU high-level waste

International Nuclear Information System (INIS)

Strathdee, G.G.; McIntyre, N.S.; Taylor, P.

1979-01-01

This paper covers the results of analyses of two radioactive nepheline syenite glass blocks recovered from in-ground leaching experiments at the Chalk River Nuclear Laboratories. Current research on borosilicate glasses for immobilization of high-level waste is also described

Assessing inventories of past radioactive waste arisings at Chalk River Laboratories

International Nuclear Information System (INIS)

Csullog, G.W.; TerHuurne, M.A.; Miller, M.T.; Edwards, N.W.; Hulley, V.R.; McCann, D.J.

1998-01-01

Internationally, a great deal of progress has been made in improving the management of currently accumulating and anticipated future radioactive wastes. Progress includes improved waste collection, segregation, characterization and documentation in support of disposal facility licensing and operation. These improvements are not often very helpful for assessing the hazards of wastes collected prior to their implementation, since, internationally, historic radioactive wastes were not managed and documented according to today's methods. This paper provides an overview of Atomic Energy of Canada Limited's (AECL) unique approach to managing its currently accumulating, low-level radioactive wastes at Chalk River Laboratories (CRL) and it describes the novel method AECL-CRL has developed to assess its historic radioactive wastes. Instead of estimating the characteristics of current radioactive wastes on a package-by-package basis, process knowledge is used to infer the average characteristics of most wastes. This approach defers, and potentially avoids, the use of expensive analytical technologies to characterize wastes until a reasonable certainty is gained about their ultimate disposition (Canada does not yet have a licensed radioactive waste disposal facility). Once the ultimate disposition is decided, performance assessments determine if inference characterization is adequate or if additional characterization is required. This process should result in significant cost savings to AECL since expensive, resource-intensive, up-front characterization may not be required for low-impact wastes. In addition, as technological improvements take place, the unit cost of characterization usually declines, making it less expensive to perform any additional characterization for current radioactive wastes. The WIP-III data management system is used at CRL to 'warehouse' the average characteristics of current radioactive wastes. This paper describes how this 'warehouse of information

Nano sized clay detected on chalk particle surfaces

DEFF Research Database (Denmark)

Skovbjerg, Lone; Hassenkam, Tue; Makovicky, Emil

2012-01-01

that in calcite saturated water, both the polar and the nonpolar functional groups adhere to the nano sized clay particles but not to calcite. This is fundamentally important information for the development of conceptual and chemical models to explain wettability alterations in chalk reservoirs...

Marine macrofossil communities in the uppermost Maastrichtian chalk of Stevns Klint, Denmark

DEFF Research Database (Denmark)

Hansen, Thomas; Surlyk, Finn

2014-01-01

Three successive marine habitats and their benthic macrofossil communities have been recognised and assessed in the uppermost Maastrichtian chalk of Stevns Klint, Denmark. The mound-bedded lower Sigerslev Member was deposited below the photic zone under the influence of persistent, non-erosive bo......Three successive marine habitats and their benthic macrofossil communities have been recognised and assessed in the uppermost Maastrichtian chalk of Stevns Klint, Denmark. The mound-bedded lower Sigerslev Member was deposited below the photic zone under the influence of persistent, non...

TASCC newsletter volume 9 no. 1

International Nuclear Information System (INIS)

Thomson, L.

1995-01-01

A newsletter produced by Chalk River's Tandem Accelerator Superconducting Cyclotron Facility. Included in this January issue of TASCC is an update of the facility, news on distribution of Nuclear Physics News International, installation of the Penning trap mass spectrometer, workshop to be held in June on nuclear physics research, and a listing of January's experiments. 1 fig

The Independence of the Nuclear Regulator: Notes from the Canadian Experience

International Nuclear Information System (INIS)

MacKenzie, B.

2010-01-01

The firing of Linda Keen as president and chief executive Officer of the Canadian Nuclear Safety Commission provoked considerable debate within Canada and internationally about the independence of the canadian nuclear regulator. ms. Keen was dismissed from her position from her position at the height of the crisis over a world-wide shortage of medical isotopes caused by the shutdown of the research reactor in Chalk river, Ontario. Under the terms of its licence, the reactor was required to have cooling pumps connected to an emergency power supply as a backup in case of a power outage caused by an event such an earthquake. In november 2007, after it was discovered that the pumps were not connected, the reactor was shut down. As panic over the shortage of medical isotopes grew, the government took three extraordinary measures: first, it issued a directive; second, it introduced emergency legislation in Parliament; and finally, it fired Linda Keen as President of the Commission. This paper examines those three measures and whether they constituted an unwarranted interference with the independence of the Canadian nuclear regulator. (N.C.)

A web-based nuclear simulator using RELAP5 and LabVIEW

International Nuclear Information System (INIS)

Kim, K.D.; Rizwan-uddin

2007-01-01

A web-based nuclear reactor simulator has been developed using the best-estimate nuclear system analysis code RELAP5 as its engine, and LabVIEW for graphical user interface and web-casting. Simulator retains the accuracy of the best-estimate code. Results are displayed in user friendly graphical format. Color-coded nominal values are displayed along with the current status of different variables in tab activated windows. Some variables of interest are also shown as a function of time. All graphical outputs are displayed in web browsers making the simulator's front end independent of the operating system. The interactive simulation feature allows the users to simulate specific reactor transients - such as LOCA, scram, etc. - using a single click. Simulator's graphical output can be web-casted and is thus available to anybody with access to the web. Moreover, if permitted, the simulator can be operated remotely from another site connected to the server via the World Wide Web

Diagenetic Variations between Upper Cretaceous Outcrop and Deeply Buried Reservoir Chalks of the North Sea Area

DEFF Research Database (Denmark)

Hjuler, Morten Leth; Fabricius, Ida Lykke

2007-01-01

-particle connections and less altered particle shapes. The non-carbonate mineralogy of outcrop chalks is dominated by quartz, occasionally opal-CT and clinoptilolite, and the clay mineral smectite. In offshore chalks quartz still dominates, opal-CT has recrystallized into submicron-size quartz crystals and smectite...

Progress report, October 1 to December 31, 1959. Physics Division

International Nuclear Information System (INIS)

1959-01-01

This is a progress report of the Physics Division at Chalk River Nuclear Laboratories from October 1, to December 31, 1959. It describes the research in nuclear physics, general physics, theoretical physics and electronics. The research areas covered in this report include nuclear structure, the tandem accelerator, particle detector development, developments in electronics, neutron decay, beta ray spectrometer, fission studies, electronics development and neutron transport theory.

Large-signal, dynamic simulation of the slowpoke-3 nuclear heating reactor

International Nuclear Information System (INIS)

Tseng, C.M.; Lepp, R.M.

1983-07-01

A 2 MWt nuclear reactor, called SLOWPOKE-3, is being developed at the Chalk River Nuclear Laboratories (CRNL). This reactor, which is cooled by natural circulation, is designed to produce hot water for commercial space heating and perhaps generate some electricity in remote locations where the costs of alternate forms of energy are high. A large-signal, dynamic simulation of this reactor, without closed-loop control, was developed and implemented on a hybrid computer, using the basic equations of conservation of mass, energy and momentum. The natural circulation of downcomer flow in the pool was simulated using a special filter, capable of modelling various flow conditions. The simulation was then used to study the intermediate and long-term transient response of SLOWPOKE-3 to large disturbances, such as loss of heat sink, loss of regulation, daily load following, and overcooling of the reactor coolant. Results of the simulation show that none of these disturbances produce hazardous transients

REDNET: a distributed data acquisition system for a nuclear research reactor

International Nuclear Information System (INIS)

Shah, R.R.; Pensom, C.F.

1984-05-01

Experimental facilities such as those in the NRU nuclear research reactor at the Chalk River Nuclear Laboratories (CRNL) need a data acquisition system that combines high performance with flexibility. The REactor Data NETwork (REDNET) is a system being developed at CRNL that used distributed computer technology to meet demanding requirements. This paper describes the distributed architecture of REDNET, comprising 7 minicomputers, and presents an overview of the software configuration and data structures which have been designed to produce a versatile and interactive system that must gather and store data at rates ranging from 20 times a second to once every 30 minutes. Each experimenter is provided with a unique set of points that are referred to collectively, and manipulated together as a group. Facilities are provided to modify operating parameters for and view data values in a group without affecting other groups. Facilities incorporated for graceful degradation of REDNET and automatic recovery from failures are also described

Impact of nuclear power plants of the PWR-type on river water quality (case-report of the river Meuse)

International Nuclear Information System (INIS)

Masschelein, W.J.; Genot, J.

1982-01-01

Five years' experience with data of the TAILFER plant located 48 km downstream of the nuclear power site of CHOOZ is reported so as to provide guidelines for the examination of future nuclear cases. The factors considered are: the reduction in water flow and thermal impacts, the discharge of nuclear active effluents and the physico-chemical impact of enrichment in salts and suspended matter. Primary importance must be given to the proportion of the discharges in terms of added (instantaneous) volume activities. In the case of inland rivers the most active effluents, including the particular isotope tritium, are contained in a reduced volume (1400 m 3 /1000 MWe), and are best evacuated to other sites. Guidelines to check the river water quality are based on the measurement of 3H, total γ, and specifically, Co 60 , Cs 137 , Mn 54 , Co 58 , and Cs 134 . Flow measurement and river transfer modelling must be part of the study of the impact as illustrated by this case-report. (author)

Chalk porosity and sonic velocity versus burial depth

DEFF Research Database (Denmark)

Fabricius, Ida Lykke; Gommesen, Lars; Krogsbøll, Anette Susanne

2008-01-01

Seventy chalk samples from four formations in the overpressured Danish central North Sea have been analyzed to investigate how correlations of porosity and sonic velocity with burial depth are affected by varying mineralogy, fluid pressure, and early introduction of petroleum. The results show th...... for fluid pressure because the cementing ions originate from stylolites, which are mechanically similar to fractures. We find that cementation occurs over a relatively short depth interval.......Seventy chalk samples from four formations in the overpressured Danish central North Sea have been analyzed to investigate how correlations of porosity and sonic velocity with burial depth are affected by varying mineralogy, fluid pressure, and early introduction of petroleum. The results show...... that porosity and sonic velocity follow the most consistent depth trends when fluid pressure and pore-volume compressibility are considered. Quartz content up to 10% has no marked effect, but more than 5% clay causes lower porosity and velocity. The mineralogical effect differs between P-wave and shear velocity...

An investigation of the suitability of the Chalk River site to host a geologic waste management facility for CRL's low and intermediate level wastes

International Nuclear Information System (INIS)

Thompson, P.; Baumgartner, P.; Chan, T.; Kitson, C.; Kozak, E.; Man, A.; Martino, J.; Stroes-Gascoyne, S.; Beaton, D.; Sharp, K.; Thivierge, R.

2011-01-01

Atomic Energy of Canada Limited (AECL) is investigating the suitability of the Chalk River Laboratories (CRL) site for hosting a Geologic Waste Management Facility (GWMF) as part of the Nuclear Legacy Liabilities Program (NLLP) funded through Natural Resources Canada (NRCan). The GWMF is envisioned to be an underground engineered-geological repository consisting of shafts, access tunnels and emplacement caverns located at a nominal depth of 500 to 1000 m in the bedrock at the CRL site. A 5-year-long pre-project study was started in 2006 to assess the feasibility of the bedrock at the CRL site to host a GWMF. The pre-project feasibility study began with a review of various previous geological investigations performed in the bedrock at the CRL site. The 2006-2010 pre-project feasibility study involved exploring the geoscience and engineering characteristics of the bedrock to depths of over one kilometre at the CRL site through surface investigations and the drilling and testing of seven new deep characterization boreholes into the CRL bedrock. The collected information and interpretations were used to construct three-dimensional (3D) deterministic computer models of the geology of the bedrock at the CRL site and surrounding area and of the associated groundwater-flow regime. In order to technically assess the suitability of the CRL site, the GWMF feasibility study has conservatively assumed that all of the legacy and forecast Low and Intermediate Level Waste (LILW) at CRL would report to it. The 3D deterministic models were used within a preliminary performance and safety assessment model to assess the long-term safety of a hypothetical GWMF at the CRL site on the basis of future radionuclide and toxic substance releases. Other items important to a preliminary performance and safety assessment include an inventory of CRL's radioactive wastes and other contaminants that could be placed in the GWMF, the creation of the engineered waste emplacement rooms and

Seismic geomorphology and origin of diagenetic geobodies in the Upper Cretaceous Chalk of the North Sea Basin (Danish Central Graben)

DEFF Research Database (Denmark)

Smit, F. W. H.; van Buchem, F.S.P.; Holst, J.H.

2018-01-01

that the geobodies are of an open-system diagenetic origin caused by ascending basin fluids guided by faults and stratigraphic heterogeneities. Increased amounts of porosity-occluding cementation, contact cement and/or high-density/-velocity minerals caused an impedance contrast that can be mapped in seismic data...... failure, followed by local mechanical compaction of high-porous chalks, paired with 2) ascension of basinal diagenetic fluids along fault systems that locally triggered cementation of calcite and dolomite within the chalk, causing increased contact cements and/or reducing porosity. The migration pathway...... of the fluids is marked by the SCRs, which are the outlines of high-density bodies of chalk nested in highly porous chalks. This study thus provides new insights into the 3D relationship between fault systems, fluid migration and diagenesis in chalks, and has important applications for basin modeling...

Changes in Specific Surface as observed by NMR, caused by saturation of Chalk with porewater bearing divalent Ions

DEFF Research Database (Denmark)

Katika, Konstantina; Addassi, Mouadh; Alam, Mohammad Monzurul

2014-01-01

Nuclear Magnetic Resonance (NMR) spectrometry has proved to be a good technique for determining the petrophysical properties of reservoir rocks; such as porosity and pore size distribution. We investigated how pore water rich in divalent ions affect the NMR signal from chalk with two different de......-to-volume ratio of the pore space. The results of this work could benefit the ongoing study on the optimization of the water composition for Enhanced Oil Recovery (EOR) methods and shed light on how it can affect the mechanical and physical properties of the rock....

INMACS: Operating experience of a mature, computer-assisted control system for nuclear material inventory and criticality safety

International Nuclear Information System (INIS)

Ross, A.M.

1983-01-01

This paper describes the operating experience of INMACS, the Integrated Nuclear Material Accounting and Control System used in the Recycle Fuel Fabrication Laboratories at Chalk River. Since commissioning was completed in 1977, INMACS has checked and recorded approximately 3000 inventory-related transactions involved in fabricating thermal-recycle fuels of (U,Pu)0 2 and (Th,Pu)0 2 . No changes have been necessary to INMACS programs that are used by laboratory staff when moving or processing nuclear material. The various utility programs have allowed efficient management and surveillance of the INMACS data base. Hardware failures and the nuisance of system unavailability at the laboratory terminals have been minimized by regular preventative maintenance. The original efforts in the design and rigorous testing of programs have helped INMACS to be accepted enthusiastically by old and new staff of the laboratories. The work required for nuclear material inventory control is done efficiently and in an atmosphere of safety

AECL research programs in life sciences

International Nuclear Information System (INIS)

Marko, A.M.

1981-04-01

The present report summarizes the current research activities in life sciences in the Atomic Energy of Canada Limited-Research Company. The research is carried out at its two main research sites: the Chalk River Nuclear Laboratories and the Whiteshell Nuclear Research Establishment. The summaries cover the following areas of research: radiation biology, medical biophysics, epidemiology, environmental research and dosimetry. (author)

Progress report: Physics Division, 1982 April 1 - June 30

International Nuclear Information System (INIS)

1982-08-01

Nuclear physics studies that took place at Chalk River Nuclear Laboratories during the second quarter of 1982 are described, as well as work in solid state and theoretical physics. The MP Tandem accelerator was shut down to prepare for the installation of a superconducting cyclotron. Computer codes developed during the period and the operation of the computer facilities are described

Structural and Lithological Controls upon Fluid Migration within the Chalk and Upper Greensand Aquifers in the Chilterns and Lambourn Downs

OpenAIRE

Thompson, Sally

2002-01-01

The influence of lithological heterogeneities, structural discontinuities and discontinuity surface mineralisation upon groundwater migration within the Chalk and the Upper Greensand of southern England has been investigated. Lithological heterogeneities in the Chalk succession include marl seams, hardgrounds, tabular flints and nodular flints. Each of these heterogeneities has a lower intrinsic porosity and permeability than in the calcite rich chalk. The influence that each of these ...

Kolmanda aastatuhande piraadid / kommenteerinud Peter Chalk ja Gordan Van Hook

Index Scriptorium Estoniae

2009-01-01

Piraatlusest Somaalia piirkonnas ja rahvusvahelistest dokumentidest piraatluse vastu võitlemiseks 21. sajandil. Kommenteerivad uurimiskeskuse RAND Corporation vanempoliitanalüütik Peter Chalk ja transpordikompanii Maersk Line innovatsiooni ja arenduse vanemdirektor Gordan Van Hook

The transport and behaviour of isoproturon in unsaturated chalk cores

Science.gov (United States)

Besien, T. J.; Williams, R. J.; Johnson, A. C.

2000-04-01

A batch sorption study, a microcosm degradation study, and two separate column leaching studies were used to investigate the transport and fate of isoproturon in unsaturated chalk. The column leaching studies used undisturbed core material obtained from the field by dry percussion drilling. Each column leaching study used 25 cm long, 10 cm wide unsaturated chalk cores through which a pulse of isoproturon and bromide was eluted. The cores were set-up to simulate conditions in the unsaturated zone of the UK Chalk aquifer by applying a suction of 1 kPa (0.1 m H 2O) to the base of each column, and eluting at a rate corresponding to an average recharge rate through the unsaturated Chalk. A dye tracer indicated that the flow was through the matrix under these conditions. The results from the first column study showed high recovery rates for both isoproturon (73-92%) and bromide (93-96%), and that isoproturon was retarded by a factor of about 1.23 relative to bromide. In the second column study, two of the four columns were eluted with non-sterile groundwater in place of the sterile groundwater used on all other columns, and this study showed high recovery rates for bromide (85-92%) and lower recovery rates for isoproturon (66-79% — sterile groundwater, 48-61% — non-sterile groundwater). The enhanced degradation in the columns eluted with non-sterile groundwater indicated that groundwater microorganisms had increased the degradation rate within these columns. Overall, the reduced isoproturon recovery in the second column study was attributed to increased microbial degradation as a result of the longer study duration (162 vs. 105 days). The breakthrough curves (BTCs) for bromide had a characteristic convection-dispersion shape and were accurately simulated with the minimum of calibration using a simple convection-dispersion model (LEACHP). However, the isoproturon BTCs had an unusual shape and could not be accurately simulated.

Progress report - Physical and Environmental Sciences - TASCC Division -1995 July 1 to December 31

Energy Technology Data Exchange (ETDEWEB)

Hardy, J C [ed.

1996-05-01

Included in this progress report of the TASCC division at Chalk River Nuclear Laboratories is the research and development being carried out at this time and a listing of the relevant publications, reports, lectures and conference contributions. The TASCC staff is also detailed. 8 tabs.,16 figs.

Progress report - Physical and Environmental Sciences - TASCC Division -1995 July 1 to December 31

International Nuclear Information System (INIS)

Hardy, J.C.

1996-05-01

Included in this progress report of the TASCC division at Chalk River Nuclear Laboratories is the research and development being carried out at this time and a listing of the relevant publications, reports, lectures and conference contributions. The TASCC staff is also detailed. 8 tabs.,16 figs

Fault zone processes in mechanically layered mudrock and chalk

Science.gov (United States)

Ferrill, David A.; Evans, Mark A.; McGinnis, Ronald N.; Morris, Alan P.; Smart, Kevin J.; Wigginton, Sarah S.; Gulliver, Kirk D. H.; Lehrmann, Daniel; de Zoeten, Erich; Sickmann, Zach

2017-04-01

A 1.5 km long natural cliff outcrop of nearly horizontal Eagle Ford Formation in south Texas exposes northwest and southeast dipping normal faults with displacements of 0.01-7 m cutting mudrock, chalk, limestone, and volcanic ash. These faults provide analogs for both natural and hydraulically-induced deformation in the productive Eagle Ford Formation - a major unconventional oil and gas reservoir in south Texas, U.S.A. - and other mechanically layered hydrocarbon reservoirs. Fault dips are steep to vertical through chalk and limestone beds, and moderate through mudrock and clay-rich ash, resulting in refracted fault profiles. Steeply dipping fault segments contain rhombohedral calcite veins that cross the fault zone obliquely, parallel to shear segments in mudrock. The vertical dimensions of the calcite veins correspond to the thickness of offset competent beds with which they are contiguous, and the slip parallel dimension is proportional to fault displacement. Failure surface characteristics, including mixed tensile and shear segments, indicate hybrid failure in chalk and limestone, whereas shear failure predominates in mudrock and ash beds - these changes in failure mode contribute to variation in fault dip. Slip on the shear segments caused dilation of the steeper hybrid segments. Tabular sheets of calcite grew by repeated fault slip, dilation, and cementation. Fluid inclusion and stable isotope geochemistry analyses of fault zone cements indicate episodic reactivation at 1.4-4.2 km depths. The results of these analyses document a dramatic bed-scale lithologic control on fault zone architecture that is directly relevant to the development of porosity and permeability anisotropy along faults.

Nuclear spectroscopic studies

International Nuclear Information System (INIS)

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1991-01-01

The Nuclear Physics group at the University of Tennessee, Knoxville is involved in several aspects of heavy-ion physics including both nuclear structure and reaction mechanisms. While our main emphasis is on experimental problems involving heavy-ion accelerators, we have maintained a strong collaboration with several theorists in order to best pursue the physics of our measurements. During the last year we have led experiments at the Holifield Heavy Ion Research Facility, the SuperHILAC at Berkeley, and Chalk River Tandem Accelerator. Also, we have joined a collaboration to study ultra-relativistic heavy ion physics and one of our group has spent all of 1987 at CERN to work on the WA80 experiment. Our experimental work is in four broad areas: (1) the structure of nuclei at high angular momentum, (2) heavy-ion induced transfer reactions, (3) the structure of nuclei far from stability, and (4) ultra-relativistic heavy-ion physics. These results will be described in this document in sections IIA, IIB, and IID, respectively. Areas (1), (3), and (4) concentrate on the structure of nuclear matter in extreme conditions of rotational motion, imbalance of neutrons and protons, or very high temperature and density. Area (2) pursues the transfer of nucleons to states with high angular momentum, both to learn about their structure and to understand the transfer of particles, energy and angular momentum in collisions between heavy ions. An important component of our program is the strong emphasis on the theoretical aspects of nuclear structure and reactions

Nuclear spectroscopic studies

International Nuclear Information System (INIS)

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1988-01-01

The Nuclear Physics group at the University of Tennessee, Knoxville is involved in several aspects of heavy-ion physics including both nuclear structure and reaction mechanisms. While our main emphasis is on experimental problems involving heavy-ion accelerators, we have maintained a strong collaboration with several theorists in order to best pursue the physics of our measurements. During the last year we have led experiments at the Holifield Heavy Ion Research Facility, the SuperHILAC at Berkeley, and Chalk River Tandem Accelerator. Also, we have joined a collaboration to study ultra-relativistic heavy ion physics and one of our group has spent all of 1987 at CERN to work on the WA80 experiment. Our experimental work is in four broad areas: (1) the structure of nuclei at high angular momentum, (2) heavy-ion induced transfer reactions, (3) the structure of nuclei far from stability, and (4) ultra-relativistic heavy-ion physics. These results will be described in this document in sections 2A, 2B, 2C, and 2D, respectively. Areas (1), (3), and (4) concentrate on the structure of nuclear matter in extreme conditions of rotational motion, imbalance of neutrons and protons or very high temperature and density. Area (2) pursues the transfer of nucleons to states with high angular momentum, both to learn about their structure and to understand the transfer of particles, energy and angular momentum in collisions between heavy ions. An important component of our program is the strong emphasis on the theoretical aspects of nuclear structure and reactions

Quantitative 1D saturation profiles on chalk by NMR

DEFF Research Database (Denmark)

Olsen, Dan; Topp, Simon; Stensgaard, Anders

1996-01-01

Quantitative one-dimensional saturation profiles showing the distribution of water and oil in chalk core samples are calculated from NMR measurements utilizing a 1D CSI spectroscopy pulse sequence. Saturation profiles may be acquired under conditions of fluid flow through the sample. Results reveal...

Nuclear research centres in the 21st century: An AECL perspective

International Nuclear Information System (INIS)

Fehrenbach, P.J.

2001-01-01

The nuclear energy programme of Canada started at Chalk River Laboratories with the setting up of Zero Energy Experimental Site in 1945. One of the early research reactors of Canada, the National Research Universal (NRU) continues to provide 70% of the world requirement of isotopes for medical and industrial applications. A CANDU prototype (208 MW(e)) came on line in 1967 and based on this concept, Canada has a large nuclear power programme. The role of nuclear research centres has evolved with time starting with strategic research in the initial phases through to implementation of technology, building and supporting industry, and carrying out advanced technology development. Most of these centres have important assets in terms of licensed sites, trained personnel, research reactors, shielded facilities and expertise for handling large quantities of radioactivity and high tech laboratories for advanced R and D. These centres would, therefore, continue to play an important role in emission free and economic energy generation, nuclear medicine, food irradiation and industrial applications. Nuclear research centres in different countries are at various stages of development and have many unique features. However, there are generic issues and much will be gained by developing a shared vision for the future and implementing programmes in a collaborative manner. (author)

Exploitation of the nuclear plant Asco and the benthic community of the river Ebro

International Nuclear Information System (INIS)

Esparza Martin

2015-01-01

The Ebro river passing through the town of Asco in the province of Tarragona, provides the necessary water for the operation of the nuclear plant. water of circulation flows and service components are returned completely to the river, or if operation of cooling towers, decreased in a small part. Evaporative losses account for approximately 1% of the total flow used for two nuclear groups. (Author)

An approach to the successful design of a minicomputer system for nuclear materials management

International Nuclear Information System (INIS)

Paul, R.N.; Anderson, L.L.

1978-08-01

A development laboratory to study nuclear fuel fabrication techniques is in operation at the Chalk River Nuclear Laboratories (CRNL). To assist operators in the management of nuclear materials in this laboratory, a minicomputer system (INMACS) has been designed and installed. INMACS is implemented on a PDP-11 with a RSTS/E operating system. A data base management package with on-line backup capability has been developed for this application. Fifteen man-years of effort have been spent on designing and building the system. This paper will discuss the philosophy and the design approach followed for the implementation of INMACS. Clear problem definition and careful system design, effective liaison with the users, detailed program specifications, proper co-ordination of the software development effort, and thorough testing of the integrated system, have all contributed to the achievement of the design goals. INMACS has been readily accepted by the users who were previously not conversant with computers. After eight months of operation, no program changes have been necessary and the system has been performing successfully as specified. (author)

Progress report April 1, to June 30, 1956. Physics Division

Energy Technology Data Exchange (ETDEWEB)

NONE

1956-07-01

This is a progress report of the Physics Division at Chalk River Nuclear Laboratories from April 1, to June 30, 1956. It describes the research in nuclear physics, general physics; theoretical physics and electronics. The research areas covered in this report include nuclear reactions, nuclear decay, neutron capture gamma ray spectra, NRX production of plutonium and its higher isotopes, slow neutron spectrometry, neutron diffraction, gamma ray crystal spectrometry, theory of binary fission and analysis of neutron scattering data.

Progress report April 1, to June 30, 1956. Physics Division

International Nuclear Information System (INIS)

1956-01-01

This is a progress report of the Physics Division at Chalk River Nuclear Laboratories from April 1, to June 30, 1956. It describes the research in nuclear physics, general physics; theoretical physics and electronics. The research areas covered in this report include nuclear reactions, nuclear decay, neutron capture gamma ray spectra, NRX production of plutonium and its higher isotopes, slow neutron spectrometry, neutron diffraction, gamma ray crystal spectrometry, theory of binary fission and analysis of neutron scattering data.

Benthic macrofauna variations and community structure in Cenomanian cyclic chalk-marl from Southerham Grey Pit, SE England

DEFF Research Database (Denmark)

Lauridsen, Bodil Wesenberg; Gale, A. S.; Surlyk, Finn

2009-01-01

Cenomanian chalk-marl couplets from England represent the 20 ka Milankovitch precession cycle. Fossil communities from both chalk and marl are identified to test if the orbital fluctuations and the associated changes in substrate lithology and climate exerted any control on the benthic macrofauna...

Acidity of sphagnum and its relation to chalk and mineral salts

Energy Technology Data Exchange (ETDEWEB)

Skene, M

1915-01-01

In addition to the criticism and elucidation of various other points, the chief conclusions which may be drawn from the preceding pages are: (1) There is a variation in acidity and in sensitiveness to chalk between the different species of sphagnum. (2) There is a correlation between degree of acidity and degree of sensitiveness. (3) The connection between the two is indirect, not direct. (4) The sphagna thrive in acid solutions: the injurious effect of chalk, and of alkalies in general, is due to the substitution of an alkaline for an acid reaction. (5) Mineral solutions are generally physiologically harmless, but may be ecologically harmful. (6) The sphagna do actually utilize in growth bases held absorbed by the acid compounds of the cell-walls.

The MAPLE-X concept dedicated to the production of radio-isotopes

International Nuclear Information System (INIS)

Heeds, W.

1985-06-01

MAPLE is a versatile new Canadian multi-purpose research reactor concept that meets the nuclear aspirations of developing countries. It is planned to convert the NRX reactor at Chalk River Nuclear Laboratories into MAPLE-X as a demonstration prototype of this concept and thereafter to dedicate its operation to the production of radio-isotopes. A description of MAPLE-X and details of molybdenum-99 production are given

Progress report: Physics Division, 1982 January 1 to March 1

International Nuclear Information System (INIS)

1982-05-01

The work of the Physics Division at Chalk River Nuclear Laboratories during the quarter is presented. Areas of interest include nuclear physics, neutron sources, the development of a superconducting cyclotron, high current proton accelerators and electron accelerators, diffraction studies and other solid state physics work in organic and inorganic substances, and computer codes. The operation of the MP tandem accelerator and the computer facilities is reviewed

Reservoir fracture mapping using microearthquakes: Austin chalk, Giddings field, TX and 76 field, Clinton Co., KY

Energy Technology Data Exchange (ETDEWEB)

Phillips, W.S.; Rutledge, J.T.; Gardner, T.L. [SPE, Richardson, TX (United States); Fairbanks, T.D.; Miller, M.E.; Schuessler, B.K. [Los Alamos National Lab., NM (United States)

1996-11-01

Patterns of microearthquakes detected downhole defined fracture orientation and extent in the Austin chalk, Giddings field, TX and the 76 field, Clinton Co., KY. We collected over 480 and 770 microearthquakes during hydraulic stimulation at two sites in the Austin chalk, and over 3200 during primary production in Clinton Co. Data were of high enough quality that 20%, 31% and 53% of the events could be located, respectively. Reflected waves constrained microearthquakes to the stimulated depths at the base of the Austin chalk. In plan view, microearthquakes defined elongate fracture zones extending from the stimulation wells parallel to the regional fracture trend. However, widths of the stimulated zones differed by a factor of five between the two Austin chalk sites, indicating a large difference in the population of ancillary fractures. Post-stimulation production was much higher from the wider zone. At Clinton Co., microearthquakes defined low-angle, reverse-fault fracture zones above and below a producing zone. Associations with depleted production intervals indicated the mapped fractures had been previously drained. Drilling showed that the fractures currently contain brine. The seismic behavior was consistent with poroelastic models that predicted slight increases in compressive stress above and below the drained volume.

Study of a conceptual nuclear energy center at Green River, Utah: water allocation issues

International Nuclear Information System (INIS)

Harper, N.J.

1982-04-01

According to preliminary studies, operation of a nine-reactor Nuclear Energy Center near Green River, Utah would require the acquisition of 126,630 acre-feet per year. Groundwater aquifers are a potential source of supply but do not present a viable option at this time due to insufficient data on aquifer characteristics. Surface supplies are available from the nearby Green and San Rafael Rivers, tributaries of the Colorado River, but are subject to important constraints. Because of these constraints, the demand for a dependable water supply for a Nuclear Energy Center could best be met by the acquisition of vested water rights from senior appropriators in either the Green or San Rafael Rivers. The Utah Water Code provides a set of procedures to accomplish such a transfer of water rights

A worker perspective on nuclear safety

International Nuclear Information System (INIS)

Pigeau, T.

2000-01-01

The majority of the 15,000 members of the Power Workers Union (PWU) are employed in electricity production at Ontario Power Generation's nuclear generating stations and in nuclear technology research at the Chalk River Laboratories of Atomic Energy of Canada Limited. Our members therefore have an obvious vested interest in any discussion related to their jobs. Workers in nuclear power plants have a clearly defined responsibility to ensure a safe working environment for themselves and their fellow workers. They have an overwhelming vested interest in ensuring that the plants are constructed, maintained, and operated safely. As will be detailed in the presentation to the CNS, all workers are required to learn and demonstrate knowledge of the hazards as an integral part of employment initiation and subsequent training. As their union, the PWU has a responsibility to ensure conditions of employment that not only permit workers to refuse work they perceive to be unsafe but require them to bring safety concerns forward for resolution to the satisfaction of both management and workers' representatives. The PWU has accomplished this through the development of workplace structures to ensure worker input is sought and acted on. The paper will describe the next steps required to improve workplace safety at Ontario Power Generation, which could be adapted to other facilities and workgroups. (author)

A preliminary study of synchrotron light sources for x-ray lithography

International Nuclear Information System (INIS)

Hoffmann, C.R.; Bigham, C.B.; Ebrahim, N.A.; Sawicki, J.A.; Taylor, T.

1989-02-01

A preliminary study of synchrotron light sources has been made, primarily oriented toward x-ray lithography. X-ray lithography is being pursued vigorously in several countries, with a goal of manufacturing high-density computer chips (0.25 μm feature sizes), and may attain commercial success in the next decade. Many other applications of soft x-rays appear worthy of investigation as well. The study group visited synchrotron radiation facilities and had discussions with members of the synchrotron radiation community, particularly Canadians. It concluded that accelerator technology for a conventional synchrotron light source appropriate for x-ray lithography is well established and is consistent with skills and experience at Chalk River Nuclear Laboratories. Compact superconducting systems are being developed also. Their technical requirements overlap with capabilities at Chalk River. (32 refs)

Reprocessing of nuclear fuels at the Savannah River Plant

International Nuclear Information System (INIS)

Gray, L.W.

1986-01-01

For more than 30 years, the Savannah River Plant (SRP) has been a major supplier of nuclear materials such as plutonium-239 and tritium-3 for nuclear and thermonuclear weapons, plutonium-238 for space exploration, and isotopes of americium, curium, and californium for use in the nuclear research community. SRP is a complete nuclear park, providing most of the processes in the nuclear fuel cycle. Key processes involve fabrication and cladding of the nuclear fuel, target, and control assemblies; rework of heavy water for use as reactor moderator; reactor loading, operation, and unloading; chemical recovery of the reactor transmutation products and spent fuels; and management of the gaseous, liquid, and solid nuclear and chemical wastes; plus a host of support operations. The site's history and the key processes from fabrication of reactor fuels and targets to finishing of virgin plutonium for use in the nuclear weapons complex are reviewed. Emphasis has been given to the chemistry of the recovery and purification of weapons grade plutonium from irradiated reactor targets

Nuclear incident monitor criticality alarm instrument for the Savannah River Site: Technical manual

International Nuclear Information System (INIS)

Jenkins, J.B.

1996-01-01

The Savannah River Site is a Department of Energy facility. The facility stores, processes, and works with fissionable material at a number of locations. Technical standards and US Department of Energy orders, require these locations to be monitored by criticality alarm systems under certain circumstances. The Savannah River Site calls such instruments Nuclear Incident Monitors or NIMs. The Sole purpose of the Nuclear Incident Monitor is to provide an immediate evacuation signal in the case of an accidental criticality in order to minimize personnel exposure to radiation. The new unit is the third generation Nuclear Incident Monitor at the Savannah River Site. The second generation unit was developed in 1979. It was designed to eliminate vacuum-tube circuits, and was the first solid state NIM at SRS. The major design objectives of the second generation NIM were to improve reliability and reduce maintenance costs. Ten prototype units have been built and tested. This report describes the design of the new NIM and the testing that took place to verify its acceptability

Wettability of Chalk and Argillaceous Sandstones Assessed from T1/T2 Ratio

DEFF Research Database (Denmark)

Katika, Konstantina; Saidian, M.; Fabricius, Ida Lykke

ratio can quantify the affinity between the rock and wetting pore fluid. The affinity is a measure directly linked to wettability. In order to investigate the T2-shortening, we performed T1-T2 NMR experiments on different samples of chalk, Berea sandstone, and chloritic greensand, saturated either...... with water, oil or oil/water at irreducible water saturation. The T1/T2 ratio obtained from T1-T2 maps reflects the T2-shortening. We compare the T1/T2 ratio for the same type of rock, saturated with different fluids. The chalk shows high affinity for water, Berea sandstone has no clear preference for oil...

Outlet from the condenser of nuclear power plant Krsko into Sava river

International Nuclear Information System (INIS)

Rek, Z.

1990-01-01

Paper deals with hot water outflow from condenser of the Nuclear power plant Krsko into river Sava. We are interested in temperature and velocity field along the river. Boundary-domain integral method is used to solve a system of conservative equations. As a result, the time development of the velocity and temperature field at nodes of discrete model is obtained. (author)

Stable isotopes

International Nuclear Information System (INIS)

Evans, D.K.

1986-01-01

Seventy-five percent of the world's stable isotope supply comes from one producer, Oak Ridge Nuclear Laboratory (ORNL) in the US. Canadian concern is that foreign needs will be met only after domestic needs, thus creating a shortage of stable isotopes in Canada. This article describes the present situation in Canada (availability and cost) of stable isotopes, the isotope enrichment techniques, and related research programs at Chalk River Nuclear Laboratories (CRNL)

Survey of physics research with a high duty cycle electron accelerator

International Nuclear Information System (INIS)

Bartholomew, G.A.; Earle, E.D.; Knowles, J.W.; Lone, M.A.

1981-02-01

The opportunities for nuclear physics research afforded by a CW electron linac with nominal energy 100 MeV and beam current >= 100 μA equipped with a bremsstrahlung monochromator and reaction product coincidence facilities are outlined. It is proposed that a program toward realization of an accelerator meeting these requirements and with provision for eventual extension to higher energies be undertaken at the Chalk River Nuclear Laboratories. (author)

Trace elements in fish from the Savannah River near Savannah River Nuclear Plant

International Nuclear Information System (INIS)

Koli, A.K.; Whitmore, R.

1983-01-01

A survey of trace element residues in fish from the Savannah River near Savannah River Nuclear Plant was undertaken in 1982. Fish muscle tissue was incubated by the wet digestion method. Fifteen trace elements were determined by flame atomic absorption spectrophotometry analysis of the digests. It was found that As, Se, Mg, Hg, Ca, Zn, and Fe levels were relatively higher than Pb, Cd, Ni, Co, Cr, and Mn in all fish species. In addition, in all fish species it seems that Pb, Cd, Ni, Co, Cr, and Mn levels were relatively higher than Cs and Cu. Cs and Cu levels were negligible in all fish species analyzed. Trace element levels found in these fish species were not high enough to render them dangerous for human consumption. (author)

Guide to Savannah River Laboratory Analytical Services Group

Energy Technology Data Exchange (ETDEWEB)

1990-04-01

The mission of the Analytical Services Group (ASG) is to provide analytical support for Savannah River Laboratory Research and Development Programs using onsite and offsite analytical labs as resources. A second mission is to provide Savannah River Site (SRS) operations with analytical support for nonroutine material characterization or special chemical analyses. The ASG provides backup support for the SRS process control labs as necessary.

Guide to Savannah River Laboratory Analytical Services Group

International Nuclear Information System (INIS)

1990-04-01

The mission of the Analytical Services Group (ASG) is to provide analytical support for Savannah River Laboratory Research and Development Programs using onsite and offsite analytical labs as resources. A second mission is to provide Savannah River Site (SRS) operations with analytical support for nonroutine material characterization or special chemical analyses. The ASG provides backup support for the SRS process control labs as necessary

Effect of fluid-solid friction on the stiffness of chalk

DEFF Research Database (Denmark)

Alam, Mohammad Monzurul; Nguh Akam, Hosea; Fabricius, Ida Lykke

2011-01-01

Chalks behave weaker at water saturated condition. We studied this softening effect as a function of Biot’s frequency ratio, which is a ratio between measured ultrasonic wave frequency and Biot critical frequency, fc. Kinematic viscosity of fluid and permeability of rock determines fc. We observe...

Burial diagenesis of deep sea chalk as reflected in Biot's coefficient

DEFF Research Database (Denmark)

Fabricius, Ida Lykke; Alam, Mohammad Monzurul

2013-01-01

to limestone as burial increases and porosity decreases. The porosity decrease is accompanied by an increasing velocity to elastic waves, and consequently a decreasing Biot's coefficient, as estimated from velocity and density of core samples. When the effective burial stress is normalized to total horizontal....... In the ooze, we find that the natural compaction causes an increasing stress on grain contact area, indicating that the ooze particles become strongly strained. In the chalk section, contact cement is probably the reason why particles become less strained as porosity declines. In the limestone, stress...... on particles apparently is low and not correlated with porosity, probably because the pore-filling cementation in this interval causes Biot's coefficient to decline as burial increases. Limestone from the water zone of the North sea Chalk Group follows the same stress trend as deep sea limestone. These results...

Inelastic Scattering of Neutrons in Solids and Liquids. V. II. Proceedings of the Symposium on Inelastic Scattering of Neurons in Solids and Liquids

Energy Technology Data Exchange (ETDEWEB)

NONE

1963-01-15

The Chalk River Symposium on Inelastic Scattering of Neutrons in Solids and Liquids was the International Atomic Energy Agency's second symposium held on this subject. The previous one was held in 1960 in Vienna and the very first international meeting in this field took place in 1957 in Stockholm. At the Stockholm meeting only 11 papers from six countries were presented; this was the very beginning of a rapidly developing new branch of physics. At the Vienna Symposium there were 50 papers from 12 countries. At Chalk River 67 papers from 13 countries and three international organizations, the European Atomic Energy Community, the Joint Institute for Nuclear Research and the International Atomic Energy Agency, were presented and discussed. In several other countries, either research in this field has already begun or preparations to start it are under way. This is an indication that the interest in using inelastic scattering of neutrons as a method to study the internal dynamics of solids, liquids and molecules is continuously increasing. On the other hand, a deeper knowledge of the dynamic properties of moderators plays an important role in the understanding of the process of thermalization of neutrons. The latter study is of special importance in promoting advances in nuclear reactor technology. In the light of these developments the International Atomic Energy Agency, with the co-sponsorship of the United Nations Educational, Scientific and Cultural Organization, organized the Symposium at Chalk River from 10 to 14 September 1962 on the generous invitation of the Government of Canada and Atomic Energy of Canada Limited.

Capillary fringe and tritium and nitrogen tracing history in the Senonian chalk of Champagne

International Nuclear Information System (INIS)

Ballif, J.L.

1998-01-01

In the middle of Champagne-Ardenne area, a chalky zone is located, directly on top of which lies the soil and in which the water table is relatively close the soil; which allows for capillary direction to the surface horizons and the renewal of water reserve. After the presentation of the hydrological characteristics, the total porosity of chalk, the pores distribution, the capillary attraction is shown by the hydrological comportment of the soil and the upper part of the unsaturated zone of chalk. In the homogeneous rock, the tritium and nitrogen transfers reveal the historical tracks. (authors)

Managing Injected Water Composition To Improve Oil Recovery: A Case Study of North Sea Chalk Reservoirs

DEFF Research Database (Denmark)

Zahid, Adeel; Shapiro, Alexander; Stenby, Erling Halfdan

2012-01-01

of the temperature dependence of the oil recovery indicated that the interaction of the ions contained in brine with the rock cannot be the only determining mechanism of enhanced recovery. We observed no substitution of Ca2+ ions with Mg2+ ions at high temperatures for both rocks. Not only the injection brine......In recent years, many core displacement experiments of oil by seawater performed on chalk rock samples have reported SO42–, Ca2+, and Mg2+ as potential determining ions for improving oil recovery. Most of these studies were carried out with outcrop chalk core plugs. The objective of this study...... is to investigate the potential of the advanced waterflooding process by carrying out experiments with reservoir chalk samples. The study results in a better understanding of the mechanisms involved in increasing the oil recovery with potential determining ions. We carried out waterflooding instead of spontaneous...

Waveform analysis of crosshole GPR data collected in heterogeneous chalk deposits

DEFF Research Database (Denmark)

Keskinen, Johanna; Nielsen, Lars; Zibar, Majken Caroline Looms

2014-01-01

Chalks are important reservoirs for groundwater production onshore Denmark and for hydrocarbons in the North Sea Basin. Therefore this rock type is studied extensively with geological and geophysical methods. Ground-penetrating radar (GPR) tomography is used to characterize fine-scale reservoir...

Geologic feasibility of selected chalk-bearing sequences within the conterminous United States with regard to siting of radioactive-waste repositories

International Nuclear Information System (INIS)

Gonzales, S.

1975-11-01

Various geologic and hydrologic parameters are evaluated in relation to assessing the potential for repository storage of high-level radioactive wastes within several stratigraphic sequences dominated by chalks and chalky limestones. The former lithology is defined as a carbonate rock consisting mainly of very fine-grained particles of micritic calcite. Although chalks also contain coarser-grained particles such as shells of fossil foraminifera and non-calcitic minerals like quartz, most contain more than 90 percent micritic material. The latter represents broken fossil coccolith plates. The chalk-dominated formations discussed are exposed and underlie two different physiographic provinces which nevertheless display a general similarity in both being regions of extensive plains. The Niobrara Formation occurs mainly within the Great Plains province, while the Austin Chalk of Texas and the Selma Group of Alabama and Mississippi are located in the western and eastern Gulf Coastal Plain, respectively. The preliminary assessment is that chalk-bearing sequences show some promise and are deserving of added consideration and evaluation. Containment for hundreds of thousands of years would seem possible given certain assumptions. The most promising units from the three studied are the Niobrara Formation and Selma Group. Regional and local conditions make the Austin more suspect

Influence of clay and silica on permeability and capillary entry pressure of chalk reservoirs in the North Sea

DEFF Research Database (Denmark)

Røgen, Birte; Fabricius, Ida Lykke

2002-01-01

specific surface area. Fifty-nine Tor and Ekofisk Formation chalk samples from five North Sea chalk reservoirs were investigated. All contain quartz and clay minerals, most commonly kaolinite and smectite, with trace amounts of illite. The contents of calcite and quartz are inversely correlated and both......)): calcite between 0.5 and 3.5, quartz about 5, kaolinite about 15, and smectite about 60....

Electroosmotic dewatering of chalk sludge, iron hydroxide sludge, wet fly ash and biomass

Energy Technology Data Exchange (ETDEWEB)

Hansen, H.K.; Kristensen, I.V.; Ottosen, L.M.; Villumsen, A. [Dept. of Geology and Geotechnical Engineering, The Technical Univ. of Denmark, Lyngby (Denmark)

2001-07-01

Electroosmotic dewatering has been tested in laboratory cells for 4 different porous materials: chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge from enzyme production. In all cases it was possible to remove water when passing electric DC current through the material. Casagrande's coefficients for the three materials where determined at different water contents. In the electroosmotic experiments shown in this work chalk can be dewatered from 40% to 79% DM (dry matter), fly ash from 75 to 82% DM, iron hydroxide sludge from 2.7 to 19% DM and biomass from 3 to 33% DM. The process was not optimised indicating that higher dry matter contents could be achieved. (orig.)

Nuclear Material Processing at the Savannah River Site

International Nuclear Information System (INIS)

Severynse, T.F.

1998-07-01

Plutonium production for national defense began at Savannah River in the mid-1950s, following construction of production reactors and separations facilities. Following the successful completion of its production mission, the site's nuclear material processing facilities continue to operate to perform stabilization of excess materials and potentially support the disposition of these materials. A number of restoration and productivity improvement projects implemented in the 1980s, totaling nearly a billion dollars, have resulted in these facilities representing the most modern and only remaining operating large-scale processing facilities in the DOE Complex. Together with the Site's extensive nuclear infrastructure, and integrated waste management system, SRS is the only DOE site with the capability and mission of ongoing processing operations

Groundwater conversion areas in chalk in the southern Frankish Alps

International Nuclear Information System (INIS)

Pfaff, T.

1987-01-01

In order to collect hydro-geological data, chalk water marking was done and/or interpreted, water balances were produced, the contents tritium, oxygen 18, calcium, magnesium and the groundwater temperatures and electrolytic conductivity of the groundwater were examined and the dry weather drainage of individual sources was analysed. (orig./PW) [de

Studies of reactor waste conditioning and disposal at CRNL

International Nuclear Information System (INIS)

Beamer, N.V.; Bourne, W.T.; Buckely, L.P.; Pettipas, W.H.; Burrill, K.A.; Dixon, D.F.; Charlesworth, D.H.

1982-09-01

This report is a compilation of five papers presented at the Second Annual Meeting of the Canadian Nuclear Society in Ottawa, 1981 June. These papers describe recent progress in studies being conducted at the Chalk River Nuclear Laboratories related to the permanent disposal of low-and intermediate-level wastes arising in the Canadian nuclear industry. The principal topics discussed include waste processing by incineration, ultrafiltration and reverse osmosis, immobilization in bitumen and glass, and also the strategy for disposal of the conditioned wastes

High resolution microgravity investigations for the detection and characterisation of subsidence associated with abandoned, coal, chalk and salt mines

Energy Technology Data Exchange (ETDEWEB)

Styles, P.; Toon, S.; Branston, M.; England, R. [Keele Univ., Applied And Environmental Geophysics Group, School of Physical and Geographical Sciences (United Kingdom); Thomas, E.; Mcgrath, R. [Geotechnology, Neath (United Kingdom)

2005-07-01

The closure and decay of industrial activity involving mining has scarred the landscape of urban areas and geo-hazards posed by subsurface cavities are ubiquitous throughout Europe. Features of concern consist of natural solution cavities (e.g. swallow holes and sinkholes in limestone gypsum and chalk) and man-made cavities (mine workings, shafts) in a great variety of post mining environments, including coal, salt, gypsum, anhydrite, tin and chalk. These problems restrict land utilisation, hinder regeneration, pose a threat to life, seriously damage property and services and blight property values. This paper outlines the application of microgravity techniques to characterise abandoned mining hazard in case studies from Coal, Chalk and Salt Mining environments in the UK. (authors)

High resolution microgravity investigations for the detection and characterisation of subsidence associated with abandoned, coal, chalk and salt mines

International Nuclear Information System (INIS)

Styles, P.; Toon, S.; Branston, M.; England, R.; Thomas, E.; Mcgrath, R.

2005-01-01

The closure and decay of industrial activity involving mining has scarred the landscape of urban areas and geo-hazards posed by subsurface cavities are ubiquitous throughout Europe. Features of concern consist of natural solution cavities (e.g. swallow holes and sinkholes in limestone gypsum and chalk) and man-made cavities (mine workings, shafts) in a great variety of post mining environments, including coal, salt, gypsum, anhydrite, tin and chalk. These problems restrict land utilisation, hinder regeneration, pose a threat to life, seriously damage property and services and blight property values. This paper outlines the application of microgravity techniques to characterise abandoned mining hazard in case studies from Coal, Chalk and Salt Mining environments in the UK. (authors)

A prototype NDT inspection data bank

International Nuclear Information System (INIS)

Wells, N.S.

1978-01-01

Existing reliability data banks provide information on items with catastrophic failure modes. However, many system components in a nuclear generating station, e.g., the steam generators, have a time-dependent degradation failure mode. Non-destructive tests associated with this failure mode require a different data base to permit predictive estimates of the component service life and performance. A data base suitable for this failure mode is presently being tested at Chalk River Nuclear Laboratories. (author)

Identifying evidence of climate change impact on extreme events in permeable chalk catchments

Science.gov (United States)

Butler, A. P.; Nubert, S.

2009-12-01

The permeable chalk catchments of southern England are vital for the economy and well being of the UK. Not only important as a water resource, their freely draining soils support intensive agricultural production, and the rolling downs and chalk streams provide important habitants for many protected plant and animal species. Consequently, there are concerns about the potential impact of climate change on such catchments, particularly in relation to groundwater recharge. Of major concern are possible changes in extreme events, such as groundwater floods and droughts, as any increase in the frequency and/or severity of these has important consequences for water resources, ecological systems and local infrastructure. Studies of climate change impact on extreme events for such catchments have indicated that, under medium and high emissions scenarios, droughts are likely to become more severe whilst floods less so. However, given the uncertainties in such predictions and the inherent variability in historic data, producing definitive evidence of changes in flood/drought frequency/severity poses a significant challenge. Thus, there is a need for specific extreme event statistics that can be used as indicators of actual climate change in streamflow and groundwater level observations. Identifying such indicators that are sufficiently robust requires catchments with long historic time series data. One such catchment is the River Lavant, an intermittent chalk stream in West Sussex, UK. Located within this catchment is Chilgrove House, the site of the UK’s longest groundwater monitoring well (with a continuous record of water level observations of varying frequency dating back to 1836). Using a variety of meteorological datasets, the behaviour of the catchment has been modelled, from 1855 to present, using a 'leaky aquifer' conceptual model. Model calibration was based on observed daily streamflow, at a gauging station just outside the town of Chichester, from 1970. Long

Advanced LabVIEW Labs

International Nuclear Information System (INIS)

Jones, Eric D.

1999-01-01

In the world of computer-based data acquisition and control, the graphical interface program LabVIEW from National Instruments is so ubiquitous that in many ways it has almost become the laboratory standard. To date, there have been approximately fifteen books concerning LabVIEW, but Professor Essick's treatise takes on a completely different tack than all of the previous discussions. In the more standard treatments of the ways and wherefores of LabVIEW such as LabVIEW Graphical Programming: Practical Applications in Instrumentation and Control by Gary W. Johnson (McGraw Hill, NY 1997), the emphasis has been instructing the reader how to program LabVIEW to create a Virtual Instrument (VI) on the computer for interfacing to a particular instruments. LabVIEW is written in ''G'' a graphical programming language developed by National Instruments. In the past the emphasis has been on training the experimenter to learn ''G''. Without going into details here, ''G'' incorporates the usual loops, arithmetic expressions, etc., found in many programming languages, but in an icon (graphical) environment. The net result being that LabVIEW contains all of the standard methods needed for interfacing to instruments, data acquisition, data analysis, graphics, and also methodology to incorporate programs written in other languages into LabVIEW. Historically, according to Professor Essick, he developed a series of experiments for an upper division laboratory course for computer-based instrumentation. His observation was that while many students had the necessary background in computer programming languages, there were students who had virtually no concept about writing a computer program let alone a computer- based interfacing program. Thus the beginnings of a concept for not only teaching computer- based instrumentation techniques, but aiso a method for the beginner to experience writing a com- puter program. Professor Essick saw LabVIEW as the ''perfect environment in which to

The main achievements of the 'Systematic approach for nuclear knowledge transfer and preservation in Romania' project

International Nuclear Information System (INIS)

Balaceanu, V.; Constantin, M.; Apostol, M.

2009-01-01

The objective of this paper is to highlight the main results of the Contract No. 13971/RO which was performed in the frame of the IAEA Coordinated Research Program (CRP) on 'Comparative Analysis of Methods and Tools for Nuclear Knowledge Preservation'. The title of the Romanian project was 'Systematic approach for Nuclear Knowledge Transfer and Preservation in Romania'. The partners which were involved in this Program: Bulgaria (Kozloduy NPP and Technical University of Sofia), Canada (Chalk River Laboratories, AECL), Jordan (Water Authority of Jordan), the Philippines (Philippines Nuclear Research Institute), Romania (Institute for Nuclear Research), the Russian Federation (Inter DCM. Corp., a subsidiary of RRC Kurchatov Institute) and the European Commission (Institute of Energy, DG Joint Research). Among the main results obtained in this work we must specify the development of an INR short/medium strategy concerning the professional knowledge management, based on an assessment of the status of the knowledge transfer and preservation. This documentation was made using some adequate tools like a specific questionnaire for highlighting the experts' motivation for transferring their knowledge and an appropriate method for the knowledge loss risk assessment. Therewith, we mention our participation in the developing of an IAEA TEC-DOC concerning the problem of nuclear knowledge transfer and preservation. (authors)

Detection of defects in logs using computer assisted tomography (CAT) scanning

International Nuclear Information System (INIS)

Tonner, P.D.; Lupton, L.R.

1985-01-01

The Chalk River Nuclear Laboratories of AECL have performed a preliminary feasibility study on the applicability of computer assisted tomographic techniques to detect the internal structure of logs. Cross sections of three logs have been obtained using a medical CAT scanner. The results show that knots, rot and growth rings are easily recognized in both dry and wet logs

Progress report - Physical and Environmental Sciences - Physics Division, 1995 January 1 to December 31

International Nuclear Information System (INIS)

Harvey, M.

1996-05-01

This document is a Progress Report for the Physical and Environmental Sciences, Physics Division, for the period 1995 January 1 to December 31, at the Chalk River nuclear Labs. The condensed matter science group continued to operate a multi-faceted program involving collaborative basic and applied research with external scientists in the fields of materials science, physics, chemistry and biology. The Applied Neutron Diffraction for Industry (And) program gained strength with ever wider applications for the nuclear, aerospace, and manufacturing programs. Steps continued towards making neutron scattering facilities at NRU reactor more user friendly. The neutrino physics group, as part of the Sudbury Neutrino Observatory (SNO) Institute, collaborating with scientists from Canada, USA and UK. The accelerator physics group spent considerable effort working with materials and fuels scientists to show the value of accelerators as an out-reactor source of radiation. Specific research activities have included the demonstration of laser plasma deposition of diamond coating, which has potential application for high-wear components in reactors, and the study for a Free Electron Laser upgrade for the IMPELA accelerator. As a result of funding reduction all programs of the Division were dissolved as of 1997 March 31

Progress report - Physical and Environmental Sciences - Physics Division, 1995 January 1 to December 31

Energy Technology Data Exchange (ETDEWEB)

Harvey, M. (ed.)

1996-05-01

This document is a Progress Report for the Physical and Environmental Sciences, Physics Division, for the period 1995 January 1 to December 31, at the Chalk River nuclear Labs. The condensed matter science group continued to operate a multi-faceted program involving collaborative basic and applied research with external scientists in the fields of materials science, physics, chemistry and biology. The Applied Neutron Diffraction for Industry (And) program gained strength with ever wider applications for the nuclear, aerospace, and manufacturing programs. Steps continued towards making neutron scattering facilities at NRU reactor more user friendly. The neutrino physics group, as part of the Sudbury Neutrino Observatory (SNO) Institute, collaborating with scientists from Canada, USA and UK. The accelerator physics group spent considerable effort working with materials and fuels scientists to show the value of accelerators as an out-reactor source of radiation. Specific research activities have included the demonstration of laser plasma deposition of diamond coating, which has potential application for high-wear components in reactors, and the study for a Free Electron Laser upgrade for the IMPELA accelerator. As a result of funding reduction all programs of the Division were dissolved as of 1997 March 31.

Approaches at KAIST NICIE Lab to quantifying situation awareness in nuclear power plant MCRs

International Nuclear Information System (INIS)

Seong, Poong-Hyun; Yim, Ho-Bin; Kim, Man-Cheol; Ha, Jun-Su; Lee, Hyun-Chul; Lee, Seung-Woo

2013-01-01

Situation awareness (SA) continues to receive a considerable amount of attention from the ergonomics community. But, techniques to measure SA have normally used expert judgment or a self-rating method so far. One of the problems of these techniques is inconsistency of results. So, empirical and analytical studies on an objective and quantitative SA measurement methods have been carried out at Nuclear I and C and Information Engineering Lab (NICIE Lab) in Korea Advanced Institute of Science and Technology (KAIST). Empirical studies are based on physical and cognitive human behaviors, whereas analytical studies are mainly based on Bayesian inference. Eye movement signals and verbal protocol analysis were used for empirical approaches to obtain objective measures. FIR and SAE measures showed feasibility of an eye-tracking method for robust application. TSA score based on a verbal protocol analysis also showed its possibility of team SA (TSA) quantification. Bayesian inference was used for analytical approaches of SA quantification. The analytical quantification method was further expanded to consider some of the important human properties, and a SA modelling tool called ‘CoRSAGE, ver01” was developed. (author)

The Jefferson Lab Trigger Supervisor System

International Nuclear Information System (INIS)

Ed Jastrzembsi; David Abbott; Graham Heyes; R.W. MacLeod; Carl Timmer; Elliott Wolin

2000-01-01

We discuss the design and performance of a Trigger Supervisor System for use in nuclear physics experiments at Jefferson Lab. We also discuss the enhanced features of a new Trigger Supervisor Module now under construction

Controls on Cementation in a Chalk Reservoir

DEFF Research Database (Denmark)

Meireles, Leonardo Teixeira Pinto; Hussein, A.; Welch, M.J.

In this study, we identify different controls on cementation in a chalk reservoir. Biot’s coefficient, a measure of cementation, stiffness and strength in porous rocks, is calculated from logging data (bulk density and sonic Pwave velocity). We show that Biot’s coefficient is correlated...... to the water saturation of the Kraka reservoir and is partly controlled by its stratigraphic sub-units. While the direct causal relationship between Biot’s coefficient and water saturation cannot be extended for Biot’s coefficient and porosity, a correlation is also identified between the two, implying...

Discussing spent nuclear fuel in high school classrooms: addressing public fears through early education

International Nuclear Information System (INIS)

Winkel, S.; Sullivan, J.; Jones, S.; Sullivan, K.; Hyland, B.; Pencer, J.; Colton, A.

2013-01-01

The Inreach program combines the Deep River Science Academy (DRSA) 'learning through research' approach with state of the art communication technology to bring scientific research to high school classrooms. The Inreach program follows the DRSA teaching model where a university student tutor works on a research project with scientific staff at AECL's Chalk River Laboratories. Participating high school classes are located across Canada. The high school students learn about the ongoing research activities via weekly web conferences. In order to engage the students and encourage participation in the conferences, themed exercises linked to the research project are provided to the students. The DRSA's Inreach program uses a cost-effective internet technology to reach a wide audience, in an interactive setting, without anyone leaving their desks or offices. An example Inreach research project is presented here: an investigation of the potential of the Canadian supercritical water cooled reactor (SCWR) concept to burn transuranic elements (Np, Pu, Am, Cm) to reduce the impact of used nuclear fuel. During this project a university student worked with AECL (Atomic Energy of Canada Limited) researchers on technical aspects of the project, and high school students followed their progress and learned about the composition, hazards, and disposition options for used nuclear fuel. Previous projects included the effects of tritium on cellular viability and neutron diffraction measurement of residual stresses in automobile engines

Groundwater recharge dynamics in unsaturated fractured chalk: a case study

Science.gov (United States)

Cherubini, Claudia; Pastore, Nicola; Giasi, Concetta I.; Allegretti, Nicolaetta M.

2016-04-01

The heterogeneity of the unsaturated zone controls its hydraulic response to rainfall and the extent to which pollutants are delayed or attenuated before reaching groundwater. It plays therefore a very important role in the recharge of aquifers and the transfer of pollutants because of the presence of temporary storage zones and preferential flows. A better knowledge of the physical processes in the unsaturated zone would allow an improved assessment of the natural recharge in a heterogeneous aquifer and of its vulnerability to surface-applied pollution. The case study regards the role of the thick unsaturated zone of the Cretaceous chalk aquifer in Picardy (North of France) that controls the hydraulic response to rainfall. In the North Paris Basin, much of the recharge must pass through a regional chalk bed that is composed of a porous matrix with embedded fractures. Different types of conceptual models have been formulated to explain infiltration and recharge processes in the unsaturated fractured rock. The present study analyses the episodic recharge in fractured Chalk aquifer using the kinematic diffusion theory to predict water table fluctuation in response to rainfall. From an analysis of the data, there is the evidence of 1) a seasonal behavior characterized by a constant increase in the water level during the winter/spring period and a recession period, 2) a series of episodic behaviors during the summer/autumn. Kinematic diffusion models are useful for predict preferential fluxes and dynamic conditions. The presented approach conceptualizes the unsaturated flow as a combination of 1) diffusive flow refers to the idealized portion of the pore space of the medium within the flow rate is driven essentially by local gradient of potential; 2) preferential flow by which water moves across macroscopic distances through conduits of macropore length.

The Jefferson Lab Trigger Supervisor System

International Nuclear Information System (INIS)

Jastrzembski, E.; Abbott, D.J.; Heyes, W.G.; MacLeod, R.W.; Timmer, C.; Wolin, E.

1999-01-01

The authors discuss the design and performance of a Trigger Supervisor System for use in nuclear physics experiments at Jefferson Lab. They also discuss the enhanced features of a new Trigger Supervisor Module now under construction

78 FR 79709 - Duke Energy Florida, Inc., Crystal River Unit 3 Nuclear Generating Plant Post-Shutdown...

Science.gov (United States)

2013-12-31

... NUCLEAR REGULATORY COMMISSION [Docket No. 50-302; NRC-2013-0283] Duke Energy Florida, Inc., Crystal River Unit 3 Nuclear Generating Plant Post-Shutdown Decommissioning Activities Report AGENCY: Nuclear Regulatory Commission (NRC). ACTION: Notice of receipt; availability; public meeting; and request...

An accident involving transport of radioactive materials, Canada 1994 March

Energy Technology Data Exchange (ETDEWEB)

Keeling, F; Dunn, L E.G. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada)

1996-12-31

AECL-Chalk River Laboratories (CRL) located at Chalk River, Ontario, routinely ships radioisotopes in bulk to Nordion International Inc. in Kanata, Ontario. On 1994 March 22, an AECL vehicle carrying three packages containing radioisotopes collided with a tractor trailer carrying steel, approximately 15 km east of the Chalk River Laboratories. The AECL-CRL emergency response plan was activated. A series of post-accident meetings were held to evaluate the effectiveness of the plan and to address any identified deficiencies. AECL-CRL is continuing to work towards addressing the identified deficiencies. (author). 2 figs.

An accident involving transport of radioactive materials, Canada 1994 March

International Nuclear Information System (INIS)

Keeling, F.; Dunn, L.E.G.

1995-01-01

AECL-Chalk River Laboratories (CRL) located at Chalk River, Ontario, routinely ships radioisotopes in bulk to Nordion International Inc. in Kanata, Ontario. On 1994 March 22, an AECL vehicle carrying three packages containing radioisotopes collided with a tractor trailer carrying steel, approximately 15 km east of the Chalk River Laboratories. The AECL-CRL emergency response plan was activated. A series of post-accident meetings were held to evaluate the effectiveness of the plan and to address any identified deficiencies. AECL-CRL is continuing to work towards addressing the identified deficiencies. (author). 2 figs

Congress moves to reorganize Department of Energy labs

International Nuclear Information System (INIS)

Hanson, D.J.

1993-01-01

Two bills that would transform the missions and practices of the Department of Energy's research laboratories are moving forward in both branches of Congress. Each of the two is crafted to improve cooperative research between DOE and private industry, but the House bill goes further by making fundamental changes in lab administration. H.R. 1432 provides a clear statement of purpose for the labs. The eight missions outlined in the bill are as follows: Enhance the nation's understanding of energy production and use, with a goal of reducing reliance on imported sources of fuels; Advance nuclear science and technology for national security purposes; Assist with dismantlement of nuclear weapons and work to curb nuclear arms proliferation; Conduct fundamental research in energy-related science and technology; Assist in development of technologies for disposal of hazardous wastes, particularly nuclear waste; Work with private industry to develop generic green technologies; Conduct technology-transfer activities; and Work to improve the quality of science, math, and engineering education in the U.S

U.S./Russian lab-to-lab materials protection, control and accounting program efforts at the Institute of Inorganic Materials

International Nuclear Information System (INIS)

Ruhter, W.D.; Kositsyn, V.; Rudenko, V.; Siskind, B.; Bieber, A.; Hoida, H.; Augustson; Ehinger, M.; Smith, B.W.

1996-01-01

The All-Russian Scientific Research Institute of Inorganic Materials (VNIINM) performs research in nuclear power reactor fuel,m spent fuel reprocessing and waste management, materials science of fissionable and reactor structural materials, metallurgy, superconducting materials, and analytical sciences. VNIINM supports the Ministry of Atomic Energy of the Russian Federation (MINATOM) in technologies for fabrication and processing of nuclear fuel. As a participant in the U. S./Russian Lab-to-Lab nuclear materials protection, control and accounting (MPC ampersand A) program, VNIINM is providing evaluation, certification, and implementation of measurement methods for such materials. In 1966, VNIINM will be working with Brookhaven staff in developing and documenting material control and accounting requirements for nuclear materials in bulk form, Livermore and Los Alamos staff in testing and evaluating gamma-ray spectrometry methods for bulk materials, Los Alamos staff in test and evaluation of neutron-coincidence counting techniques, Oak Ridge staff in accounting of bulk materials with process instrumentation, and Pacific Northwest staff on automating VNIINM's coulometric titration system. In addition, VNIINM will develop a computerized accounting system for nuclear material within VNIINM and heir storage facility. This paper describes the status of this work and anticipated progress in 1996

Full-waveform inversion of cross-hole GPR data collected in a strongly heterogeneous chalk reservoir analogue with sharp permittivity and conductivity contrasts

DEFF Research Database (Denmark)

Keskinen, Johanna; Zibar, Majken Caroline Looms; Moreau, Julien

2014-01-01

Chalk sediments form an important reservoir for groundwater onshore and for hydrocarbons in the Danish sector of the North Sea. Cross-hole Ground-penetrating radar (GPR) tomography is an efficient method to investigate subtle porosity variations in the chalk. Traditional ray-based inversion...

Accelerator breeder: a viable option for the production of nuclear fuels

International Nuclear Information System (INIS)

Grand, P.

1983-01-01

Despite the growing pains of the US nuclear power industry, our dependence on nuclear energy for the production of electricity and possibly process heat is likely to increase dramatically over the next few deacades. This statement dismisses fusion as being entirely too speculative to be practical within that time frame. Sometime, between the years 2000 and 2050, fissile material will be in short supply whether it is to fuel existing LWR's or to provide initial fuel inventory for FBR's. The accelerator breeder could produce the fuel shortfall predicted to occur during the first half of the 21st century. The accelerator breeder offers the only practical means today of producing, or breeding, large quantities of fissile fuel from fertile materials, albeit at high cost. Studies performed over the last few years at Chalk River Laboratory and at Brookhaven National Laboratory have demonstrated that the accelerator breeder is practical, technically feasible with state-of-the-art technology, and is economically competitive with any other proposed synthetic means of fissile fuel production. This paper gives the parameters of a nearly optimized accelerator-breeder system, then discusses the development needs, and the economics and institutional problems that this breeding concept faces

Design and implementation progress of multi-purpose simulator for nuclear research reactor using LabVIEW

International Nuclear Information System (INIS)

Arafa, Amany Abdel Aziz; Saleh, Hassan Ibrahim; Ashoub, Nagieb

2015-01-01

This paper illustrates the neutronic and thermal hydraulic models that were implemented in the nuclear research reactor simulator based on LabVIEW. It also describes the system and transient analysis of the simulator that takes into consideration the temperature effects and poisoning. This simulator is designed to be a multi-purpose in which the operator could understand the effects of the input parameters on the reactor. A designer can study different solutions for virtual reactor accident scenarios. The main features of the simulator are the flexibility to design and maintain the interface and the ability to redesign and remodel the reactor core engine. The developed reactor simulator permits to acquire hands-on the experience of the physics and technology of nuclear reactors including reactivity control, thermodynamics, technology design and safety system design. This simulator can be easily customizable and upgradable and new opportunities for collaboration between academic groups could be conducted.

Design and implementation progress of multi-purpose simulator for nuclear research reactor using LabVIEW

Energy Technology Data Exchange (ETDEWEB)

Arafa, Amany Abdel Aziz; Saleh, Hassan Ibrahim [Atomic Energy Authority, Cairo (Egypt). Radiation Engineering Dept.; Ashoub, Nagieb [Atomic Energy Authority, Cairo (Egypt). Nuclear Research Center

2015-11-15

This paper illustrates the neutronic and thermal hydraulic models that were implemented in the nuclear research reactor simulator based on LabVIEW. It also describes the system and transient analysis of the simulator that takes into consideration the temperature effects and poisoning. This simulator is designed to be a multi-purpose in which the operator could understand the effects of the input parameters on the reactor. A designer can study different solutions for virtual reactor accident scenarios. The main features of the simulator are the flexibility to design and maintain the interface and the ability to redesign and remodel the reactor core engine. The developed reactor simulator permits to acquire hands-on the experience of the physics and technology of nuclear reactors including reactivity control, thermodynamics, technology design and safety system design. This simulator can be easily customizable and upgradable and new opportunities for collaboration between academic groups could be conducted.

Tracking selenium in the Chalk aquifer of northern France: Sr isotope constraints

International Nuclear Information System (INIS)

Cary, L.; Benabderraziq, H.; Elkhattabi, J.; Gourcy, L.; Parmentier, M.; Picot, J.; Khaska, M.; Laurent, A.; Négrel, Ph.

2014-01-01

Highlights: • We report the chemistry of the Chalk groundwater affected by Se contamination. • Strontium isotopes were used to identify the groundwater bodies and their mixings. • The spatial and temporal Se variability is mainly linked to the presence of Se-rich clays. • Saturation or desaturation of Se-rich clays control Se mobility. - Abstract: Groundwater at the southern and eastern edges of France’s Paris Basin has a selenium content that at times exceeds the European Framework Directive’s drinking-water limit value of 10 μg/L. To better understand the dynamics of the Chalk groundwater being tapped to supply the city of Lille and the Se origins, we used a combination of geochemical and isotopic tools. Strontium isotopes, coupled with Ca/Sr, Mg/Sr and Se/Sr ratios, were used to identify the main groundwater bodies and their mixings, with the Mg/Sr and Se/Sr ratios constraining a ternary system. Groundwater in the agricultural aquifer-recharge zone represents a first end-member and displays the youngest water ages of the catchment along with the highest Sr isotopic signature (0.70842) and low Se contents. Anaerobic groundwater constitutes a second major end-member affected by water-rock interactions over a long residence time, with the lowest Sr isotopic signature (0.70789) and the lowest Se content, its low SF6 content confirming the contribution of old water. Se-rich groundwater containing up to 30 μg/L of Se represents a third major end-member, with an intermediate Sr isotopic ratio (0.70826), and is mainly constrained by the clayey Se-rich formation overlying the Chalk aquifer. The spatial and temporal Se variability in the groundwater is clearly linked to the presence of this formation identified as Tertiary and also to the hydrological conditions; saturation of the Se-rich clays by oxygenated groundwater enhances Se mobility and also Sr adsorption onto the clays. This multi-tool study including Sr isotopes successfully identified the Se

Measurement of organ doses from external γ-radiation in the environment of a nuclear research laboratory

International Nuclear Information System (INIS)

Jones, A.R.

1978-06-01

Thermoluminescent dosimeters (TLD) are used to monitor the γ-ray exposure in the environment at the Chalk River Nuclear Laboratories. To relate the exposure to the doses absorbed by humans in this environment a set of measurements has been made of the doses at various sites within a phantom, placed out-of-doors, while measuring the exposure simultaneously. The measurements have been made with sensitized LiF-TLD's for exposures lasting several months in order to obtain adequate accuracy at the low exposure rates (5 - 50 μR/h) encountered. The exposure was measured with TLD's placed one metre from the ground and on four sides of the phantom and two metres away. Measurements made of the internal radioactivity of the phantom showed that this contributed less than 0.2 μR/h to the TLD's lodged within the phantom

Improvements MOIRA system for application to nuclear sites Spanish river

International Nuclear Information System (INIS)

Gallego Diaz, E.; Iglesias Ferrer, R.; Dvorzhak, A.; Hofman, D.

2011-01-01

Possible consequences of a nuclear accident must have radioactive contamination in the medium and long-term freshwater aquatic systems. Faced with this problem, it is essential to have a realistic assessment of the radiological impact, ecological, social and economic potential management strategies, to take the best decisions rationally. MOIRA is a system of decision support developed in the course of the European Framework Programmes with participation of the UPM, which has been improved and adapted to Spanish nuclear sites in recent years in the context ISIDRO Project, sponsored by the Council Nuclear, with the participation of CIEMAT and UPM. The paper focuses on these advances, primarily related to complex hydraulic systems such as rivers Tajo, Ebro and Jucar, which are located several Spanish plants.

Strength and Biot's coefficient for high-porosity oil- or water-saturated chalk

DEFF Research Database (Denmark)

Andreassen, Katrine Alling

. The Biot coefficient states the degree of cementation or how the pore pressure contributes to the strain resulting from an external load for a porous material. It is here calculated from dynamic measurements and correlated with the strength of outcrop chalk characterized by the onset of pore collapse...... during hydrostatic loading. The hypothesis is that the Biot coefficient and the theory of poroelasticity may cover the fluid effect by including the increased fluid bulk modulus from oil to water. A high number of test results for both oil- and water-saturated high-porosity outcrop chalk show correlation......In the petroleum industry it is relevant to know the Biot coefficient for establishing the effective stresses present in both the overburden and for the reservoir interval. When depleting a reservoir it is important to estimate the settlement through the strain imposed by the effective stress. Also...

Upper Cretaceous chalk facies and depositional history recorded in the Mona-1 core, Mona Ridge, Danish North Sea

Directory of Open Access Journals (Sweden)

Finn Surlyk

2011-12-01

Full Text Available The 331 m long core from the Mona-1 well in the Danish North Sea spans almost the entire Upper Cretaceous Chalk Group but only about 10% of Late Cretaceous time is represented. The succession comprises 14 facies representing pelagic deposition, turbidity flow, and mass-transport processes, including mudflow, debris flow, and slumping. Pelagic deposits vary mainly in terms of the concentration of siliciclastic material, the trace-fossil assemblage, and the presence or ab¬sence of primary sedimentary structures. Pelagic sedimentation was probably punctuated by the deposition of thin turbidites, and the resultant deposits were thoroughly bioturbated if deposited during normal oxygenation at the sea floor. Periodic benthic dysoxia resulted in the preservation of primary structures, as represented by laminated chalk which consists of thin pelagic laminae alternating with thin turbidites. In addition to the thin turbidites in the laminated chalk, four dif¬ferent turbidite facies are interpreted as representing high- to low-energy flows. Clast-supported chalk conglomerates have previously not been differentiated from other turbidites, but are here interpreted to be directly related to the down-slope evolution of debris flows. Debris flows are rep¬resented by matrix-supported conglomerates, which form one of the most common facies in the succession. High-concentration, gravity-driven suspension flows passed into dilute visco-plastic flows during the final stages of deposition and resulted in the deposition of structureless chalks. Limited shear deformation produced distinct quasi-facies from which the precursor facies can be deduced, whereas intense or continued shear deformation produced a shear-banded quasi-facies from which the precursor facies cannot be deduced in all cases. A series of major slump packages (14–18 in total are interpreted, forming over 40% of the succession; debrites appear to be the most common precursor facies involved in

Nonproliferation impacts assessment for the management of the Savannah River Site aluminum-based spent nuclear fuel

International Nuclear Information System (INIS)

1998-12-01

On May 13, 1996, the US established a new, 10-year policy to accept and manage foreign research reactor spent nuclear fuel containing uranium enriched in the US. The goal of this policy is to reduce civilian commerce in weapons-usable highly enriched uranium (HEU), thereby reducing the risk of nuclear weapons proliferation. Two key disposition options under consideration for managing this fuel include conventional reprocessing and new treatment and packaging technologies. The Record of Decision specified that, while evaluating the reprocessing option, ''DOE will commission or conduct an independent study of the nonproliferation and other (e.g., cost and timing) implications of chemical separation of spent nuclear fuel from foreign research reactors.'' DOE's Office of Arms Control and Nonproliferation conducted this study consistent with the aforementioned Record of Decision. This report addresses the nonproliferation implications of the technologies under consideration for managing aluminum-based spent nuclear fuel at the Savannah River Site. Because the same technology options are being considered for the foreign research reactor and the other aluminum-based spent nuclear fuels discussed in Section ES.1, this report addresses the nonproliferation implications of managing all the Savannah River Site aluminum-based spent nuclear fuel, not just the foreign research reactor spent nuclear fuel. The combination of the environmental impact information contained in the draft EIS, public comment in response to the draft EIS, and the nonproliferation information contained in this report will enable the Department to make a sound decision regarding how to manage all aluminum-based spent nuclear fuel at the Savannah River Site

A recommended program of tritium monitoring research and development

International Nuclear Information System (INIS)

Nickerson, S.B.; Gerdingh, R.F.; Penfold, K.

1982-10-01

This report presents recommendations for programs of research and development in tritium monitoring instrumentation. These recommendations, if implemented, will offer Canadian industry the opportunity to develop marketable instruments. The major recommendations are to assist in the development and promotion of two Chalk River Nuclear Laboratories' monitors and an Ontario Hydro monitor, and to support research and development of a surface monitor

Cw RFQ development

International Nuclear Information System (INIS)

Schriber, S.O.

1985-01-01

A review of research and development related to fabricating and operating radio-frequency quadrupole (RFQ) structures at 100% duty cycle [continuous wave (cw)] is presented, with emphasis on work at the Los Alamos National Laboratory, the Chalk River Nuclear Laboratories, and the University of Frankfurt. Activities in other areas that have an impact on operating cw RFQ systems will be highlighted. 27 refs

Exploitation of the nuclear plant Asco and the benthic community of the river Ebro; Explotacion de la central nuclear Asco y la comunidad bentonica del rio Ebro

Energy Technology Data Exchange (ETDEWEB)

Esparza Martin

2015-07-01

The Ebro river passing through the town of Asco in the province of Tarragona, provides the necessary water for the operation of the nuclear plant. water of circulation flows and service components are returned completely to the river, or if operation of cooling towers, decreased in a small part. Evaporative losses account for approximately 1% of the total flow used for two nuclear groups. (Author)

Comparison of balance of tritium activity in waste water from nuclear power plants and at selected monitoring sites in the Vltava River, Elbe River and Jihlava (Dyje) River catchments in the Czech Republic.

Science.gov (United States)

Hanslík, Eduard; Marešová, Diana; Juranová, Eva; Sedlářová, Barbora

2017-12-01

During the routine operation, nuclear power plants discharge waste water containing a certain amount of radioactivity, whose main component is the artificial radionuclide tritium. The amounts of tritium released into the environment are kept within the legal requirements, which minimize the noxious effects of radioactivity, but the activity concentration is well measurable in surface water of the recipient. This study compares amount of tritium activity in waste water from nuclear power plants and the tritium activity detected at selected relevant sites of surface water quality monitoring. The situation is assessed in the catchment of the Vltava and Elbe Rivers, affected by the Temelín Nuclear Power Plant as well as in the Jihlava River catchment (the Danube River catchment respectively), where the waste water of the Dukovany Nuclear Power Plant is discharged. The results show a good agreement of the amount of released tritium stated by the power plant operator and the tritium amount detected in the surface water and highlighted the importance of a robust independent monitoring of tritium discharged from a nuclear power plant which could be carried out by water management authorities. The outputs of independent monitoring allow validating the values reported by a polluter and expand opportunities of using tritium as e.g. tracer. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental Study of Bacterial Penetration into Chalk Rock: Mechanisms and Effect on Permeability

DEFF Research Database (Denmark)

Halim, Amalia Yunita; Shapiro, Alexander; Eliasson Lantz, Anna

2014-01-01

Bacterial selective plugging is one of the mechanisms through which microorganisms can be applied for enhanced oil recovery, as bacteria can plug the water-swept zones of a reservoir, thus altering the flow paths and improving sweep efficiency. However, complete understanding of the penetration...... behavior of bacteria is lacking, especially in chalk formations where characteristic pore throat sizes are comparable with the sizes of bacterial cells. In this study, two bacterial strains, Bacillus licheniformis 421 (spore-forming) and Pseudomonas putida K12 (non-spore forming) were used to investigate...... the penetration of bacteria into chalk and its effect on permeability reduction. The core plugs were produced from Stevns Klint outcrop with low permeability (2–4 mD) and with pore sizes comparable to bacterial sizes. Both types of bacteria were able to penetrate and to be transported through the cores to some...

The remote handling of canisters containing nuclear waste in glass at the Savannah River Plant

International Nuclear Information System (INIS)

Callan, J.E.

1986-01-01

The Defense Waste Processing Facility (DWPF) is a complete production area being constructed at the Savannah River Plant for the immobilization of nuclear waste in glass. The remote handling of canisters filled with nuclear waste in glass is an essential part of the process of the DWPF at the Savannah River Plant. The canisters are filled with nuclear waste containing up to 235,000 curies of radioactivity. Handling and movement of these canisters must be accomplished remotely since they radiate up to 5000 R/h. Within the Vitrification Building during filling, cleaning, and sealing, canisters are moved using standard cranes and trolleys and a specially designed grapple. During transportation to the Glass Waste Storage Building, a one-of-a-kind, specially designed Shielded Canister Transporter (SCT) is used. 8 figs

The use of Hewlett Packard minicomputers for data acquisition and data analysis in heat exchanger research and development

International Nuclear Information System (INIS)

Lepp, R.M.; Mastorakos, J.; Shaw, J.D.; Tromp, J.H.

1984-07-01

Failures in heat exchange equipment are usually caused by vibration-induced fatigue or fretting wear, or by corrosion. The need for high reliability and performance of this equipment, particularly in nuclear power plants, has resulted in research and development programs on heat exchangers at the Chalk River Nuclear Laboratories. Much of this work has been experimental, requiring the use of computer-based data acquisition/analysis systems. The way in which we have satisfied these needs using equipment supplied by Hewlett-Packard is described

Geologic models and evaluation of undiscovered conventional and continuous oil and gas resources: Upper Cretaceous Austin Chalk

Science.gov (United States)

Pearson, Krystal

2012-01-01

The Upper Cretaceous Austin Chalk forms a low-permeability, onshore Gulf of Mexico reservoir that produces oil and gas from major fractures oriented parallel to the underlying Lower Cretaceous shelf edge. Horizontal drilling links these fracture systems to create an interconnected network that drains the reservoir. Field and well locations along the production trend are controlled by fracture networks. Highly fractured chalk is present along both regional and local fault zones. Fractures are also genetically linked to movement of the underlying Jurassic Louann Salt with tensile fractures forming downdip of salt-related structures creating the most effective reservoirs. Undiscovered accumulations should also be associated with structure-controlled fracture systems because much of the Austin that overlies the Lower Cretaceous shelf edge remains unexplored. The Upper Cretaceous Eagle Ford Shale is the primary source rock for Austin Chalk hydrocarbons. This transgressive marine shale varies in thickness and lithology across the study area and contains both oil- and gas-prone kerogen. The Eagle Ford began generating oil and gas in the early Miocene, and vertical migration through fractures was sufficient to charge the Austin reservoirs.

U.S./Russian lab-to-lab materials protection, control and accounting program efforts at the Institute of Inorganic Materials. Revision 1

International Nuclear Information System (INIS)

Ruhter, W.D.; Kositsyn, V.; Rudenko, V.; Siskind, B.; Bieber, A.; Hoida, Hiroshi; Augustson, R.; Ehinger, M.; Smith, B.W.

1996-01-01

The All-Russian Scientific Research Institute of Inorganic Materials (VNIINM) performs research in nuclear power reactor fuel, spent fuel reprocessing and waste management, materials science of fissionable and reactor structural materials, metallurgy, superconducting materials, and analytical sciences. VNIINM supports the Ministry of Atomic Energy of the Russian Federation (MINATOM) in technologies for fabrication and processing of nuclear fuel. As a participant in the US/Russian Lab-to-Lab nuclear materials protection, control and accounting (MPC and A) program, VNIINM is providing support for measurements of nuclear materials in bulk forms by developing specifications, test and evaluation, certification, and implementation of measurement methods for such materials. In 1996, VNIINM will be working with Brookhaven staff in developing and documenting material control and accounting requirements for nuclear materials in bulk form, Livermore and Los Alamos staff in testing and evaluating gamma-ray spectrometry methods for bulk materials, Los Alamos staff in test and evaluation of neutron-coincidence counting techniques, Oak Ridge staff in accounting of bulk materials with process instrumentation, and Pacific Northwest staff on automating VNIINM's coulometric titration system. In addition, VNIINM will develop a computerized accounting system for nuclear material within VNIINM and their storage facility. The paper will describe the status of this work and anticipated progress in 1996

Controls on Cementation in a Chalk Reservoir

DEFF Research Database (Denmark)

Meireles, Leonardo Teixeira Pinto; Hussein, A.; Welch, M.J.

2017-01-01

In this study, we identify different controls on cementation in a chalk reservoir. Biot’s coefficient, a measure of cementation, stiffness and strength in porous rocks, is calculated from logging data (bulk density and sonic Pwave velocity). We show that Biot’s coefficient is correlated...... that some degree of pore filling cementation occurred in Kraka (Alam, 2010). Lack of correlation between Biot’s coefficient and Gamma Ray (GR) indicates that the small amount of clay present is generally located in the pore space, thus not contributing to frame stiffness. While there was no compositional...... control on cementation via clay, we could infer that stratigraphy impacts on the diagenetic process....

Stylolites, porosity, depositional texture, and silicates in chalk facies sediments:Ontong Java Plateau - Gorm and Tyra fields, North Sea

OpenAIRE

Fabricius, Ida Lykke; Borre, Mai K.

2007-01-01

Comparison of chalk on the Ontong Java Plateau and chalk in the Central North Sea indicates that, whereas pressure dissolution is controlled by effective burial stress, pore-filling cementation is controlled by temperature. Effective burial stress is caused by the weight of all overlying water and sediments as counteracted by the pressure in the pore fluid, so the regional overpressure in the Central North Sea is one reason why the two localities have different relationships between temperatu...

Discussing spent nuclear fuel in high school classrooms: addressing public fears through early education

Energy Technology Data Exchange (ETDEWEB)

Winkel, S. [Deep River Science Academy, 20 Forest Ave. P.O. Box 600, Deep River, Ontario K0J 1P0 (Canada); Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario, K0J 1J0 (Canada); Sullivan, J.; Jones, S.; Sullivan, K. [Deep River Science Academy, 20 Forest Ave. P.O. Box 600, Deep River, Ontario K0J 1P0 (Canada); Hyland, B.; Pencer, J.; Colton, A. [Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario, K0J 1J0 (Canada)

2013-07-01

The Inreach program combines the Deep River Science Academy (DRSA) 'learning through research' approach with state of the art communication technology to bring scientific research to high school classrooms. The Inreach program follows the DRSA teaching model where a university student tutor works on a research project with scientific staff at AECL's Chalk River Laboratories. Participating high school classes are located across Canada. The high school students learn about the ongoing research activities via weekly web conferences. In order to engage the students and encourage participation in the conferences, themed exercises linked to the research project are provided to the students. The DRSA's Inreach program uses a cost-effective internet technology to reach a wide audience, in an interactive setting, without anyone leaving their desks or offices. An example Inreach research project is presented here: an investigation of the potential of the Canadian supercritical water cooled reactor (SCWR) concept to burn transuranic elements (Np, Pu, Am, Cm) to reduce the impact of used nuclear fuel. During this project a university student worked with AECL (Atomic Energy of Canada Limited) researchers on technical aspects of the project, and high school students followed their progress and learned about the composition, hazards, and disposition options for used nuclear fuel. Previous projects included the effects of tritium on cellular viability and neutron diffraction measurement of residual stresses in automobile engines.

Gamma radiation scanning of nuclear waste storage tile holes

International Nuclear Information System (INIS)

Das, A.; Yue, S.; Sur, B.; Johnston, J.; Gaudet, M.; Wright, M.; Burton, N.

2010-01-01

Nuclear waste management facilities at Chalk River Laboratories use below-ground 'tile holes' to store solid waste from various activities such as medical radioisotope production. A silicon PIN (p-type-intrinsic-n-type semiconductor) diode based gamma radiation scanning system has been developed and used to profile the gamma radiation fields along the depth of waste storage tile holes by deploying the sensor into verification tubes adjacent to the tile holes themselves. The radiation field measurements were consistent with expected radiation fields in the tile holes based on administrative knowledge of the radioactive contents and their corresponding decay rates. Such measurements allow non-invasive verification of tile hole contents and provide input to the assessment of radiological risk associated with removal of the waste. Using this detector system, radioactive waste that has decayed to very low levels may be identified based on the radiation profile. This information will support planning for possible transfer of this waste to a licensed waste storage facility designed for low level waste, thus freeing storage space for possible tile hole re-use for more highly radioactive waste. (author)

Environmental isotope studies related to groundwater flow and saline encroachment in the chalk aquifer of Lincolnshire, England

International Nuclear Information System (INIS)

Lloyd, J.W.; Howard, K.W.F.

1978-01-01

The isotopes of tritium and carbon are used to study part of the North Lincolnshire Chalk aquifer in England. The tritium data support the view that the aquifer is a thin fissure system and indicate that some changes in flow direction have occurred due to recent abstraction. The data are also consistent with other chemical data in elucidating groundwater entering the Chalk from deeper aquifers. Carbon isotopes are used to distinguish between saline water bodies and suggest that saline water was entrapped within the aquifer in the Eemian and Flandrian stages of the Pleistocene. (orig.) [de

Progress report chemistry and materials division 1984 January 1 - June 30

International Nuclear Information System (INIS)

1984-08-01

During the first half of 1984 work in the Chemistry and Materials Division of Chalk River Nuclear Laboratories concentrated on studies of ion penetration phenomena, surface phenomena, radiation damage, radiochemical analysis, recycle fuel analysis, gamma spectrometry, mass spectrometry of fuels and moderators, analysis of hydrogen in zirconium alloys, burnup analysis, radiolysis, hydrogen isotope separation, hydrogen adsorption, zirconium corrosion, and metal physics studies of zirconium

SLOWPOKE

International Nuclear Information System (INIS)

Law, Charles.

1979-01-01

The SLOWPOKE (Safe Low Power Critical Experiment) reactor was developed by AECL at Whiteshell and Chalk River between 1968 and 1970. It is a neutron-producing reactor of low power with minimal fuel, shielding, and cooling requirements and intrinsic safety. Four Canadian universities and one German one have acquired SLOWPOKE reactors for neutron activation analyses and for student research in nuclear engineering and reactor physics. (LL)

Standard criteria for disposal of liquid radioactive wastes from nuclear power plants into surface waters (river systems)

International Nuclear Information System (INIS)

Pisarev, V.V.; Tsybizov, I.S.

1976-01-01

Radioactive products discharge into natural water streams results in the necessity to regulate nuclear power plant discharges to ensure radiation safety (RS) for population using a river and surrounding river territory. To ensure RS it is necessary to set scientific-founded standards of permissible discharge level of liquid radioactive wastes (LRW) from nuclear power plant assuring observance of hygienic requirements for surface water puring. Volume of permissible LRW discharge into river systems must be set both with provision for concrete physical-geographycal conditions, specficity of utilizing the river and river valley and social-economical peculiarities of crtical population groups. The value of permissible LRW discharge into river systems is determined by three criterion groups: radiological, ecological and hydrological ones. By means of radiological group the internal and external irradiation doses for the whole body and its separate organs are set and RS of population is determined. Ecological criteria include a number of parameters (coefficients of accumulation, distribution and transition) determining quantitative ratios between radioactive element contents in water and separate links of biological chains: soil/water, fish/water, vegetables/water and others. Hydrological criteria determine the degree of waste dilution in rivers, control radioactive contamination of flood-lands areas and in common with ecological criteria determine radionuclide contents in soil and food products. A method of determining average annual values of LRW dilution in river waters is presented [ru

Results of detailed ground geophysical surveys for locating and differentiating waste structures in waste management area 'A' at Chalk River Laboratories, Ontario

International Nuclear Information System (INIS)

Tomsons, D.K.; Street, P.J.; Lodha, G.S.

1999-01-01

Waste Management Area 'A' (WMA 'A'), located in the outer area of the Chalk River Laboratories (CRL) was in use as a waste burial site from 1946 to 1955. Waste management structures include debris-filled trenches, concrete bunkers and miscellaneous contaminated solid materials, and ditches and pits used for liquid dispersal. In order to update historical records, it was proposed to conduct detailed ground geophysical surveys to define the locations of waste management structures in WMA 'A', assist in planning of the drilling and sampling program to provide ground truth for the geophysics investigation and to predict the nature and locations of unknown/undefined shallow structures. A detailed ground geophysical survey grid was established with a total of 127 grid lines, oriented NNE and spaced one metre apart. The geophysical surveys were carried out during August and September, 1996. The combination of geophysical tools used included the Geonics EM61 metal detector, the GSM-19 magnetometer/gradiometer and a RAMAC high frequency ground penetrating radar system. The geophysical surveys were successful in identifying waste management structures and in characterizing to some extent, the composition of the waste. The geophysical surveys are able to determine the presence of most of the known waste management structures, especially in the western and central portions of the grid which contain the majority of the metallic waste. The eastern portion of the grid has a completely different geophysical character. While historical records show that trenches were dug, they are far less evident in the geophysical record. There is clear evidence for a trench running between lines 30E and 63E at 70 m. There are indications from the radar survey of other trench-like structures in the eastern portion. EM61 data clearly show that there is far less metallic debris in the eastern portion. The geophysical surveys were also successful in identifying previously unknown locations of waste

Investigated Miscible CO2 Flooding for Enhancing Oil Recovery in Wettability Altered Chalk and Sandstone Rocks

Energy Technology Data Exchange (ETDEWEB)

Tabrizy, Vahid Alipour

2012-07-01

The thesis addresses oil recovery by miscible CO2 flooding from modified sandstone and chalk rocks. Calcite mineral surface is modified with stearic acid (SA) and asphaltene, and the silicate mineral surfaces are modified with N,N-dimethyldodecylamine (NN-DMDA) and asphaltene. The stability of adsorbed polar components in presence of SO4 2- and Mg2 + ions is also investigated. Recovery from sandstone cores is consistently lower than that from chalk cores saturated with the same oil and flooded with CO2 at all miscible flooding conditions. This may be due to the larger permeability contrasts in sandstone cores, which promote the fingering phenomenon. Miscible CO2 flooding for chalk and sandstone cores with distilled water, as initial water saturation, shows also lower oil recovery than cores saturated with different ions. At higher miscible flooding conditions, higher oil recovery is obtained. However, presence of light components (such as C1 or C3) in oil reduced the recovery. Oil recovery in presence of methane (C1) is lower than that in presence of methane and propane (C1/C3). A ternary diagram was constructed in order to understand the CO2 flooding mechanism(s) at the different flooding conditions and in presence of light components. The side effect of the flooding with CO2 is the probability for asphaltene deposition. An approach based on solubility parameter in the liquid, is used to assess the risk for asphaltene deposition during CO2 miscible flooding. The light components (C1/C3) and higher flooding conditions enhanced the risk for asphaltene instability. It is also shown higher amount of asphaltene deposition in chalk cores than that in sandstone cores at similar miscibility conditions.(au)

Upper Cretaceous chalk facies and depositional history recorded in the Mona-1 core, Mona Ridge, Danish North Sea: Plate 1

Directory of Open Access Journals (Sweden)

Surlyk, Finn

2011-12-01

Full Text Available The 331 m long core from the Mona-1 well in the Danish North Sea spans almost the entire Upper Cretaceous Chalk Group but only about 10% of Late Cretaceous time is represented. The succession comprises 14 facies representing pelagic deposition, turbidity flow, and mass-transport processes, including mudflow, debris flow, and slumping. Pelagic deposits vary mainly in terms of the concentration of siliciclastic material, the trace-fossil assemblage, and the presence or ab¬sence of primary sedimentary structures. Pelagic sedimentation was probably punctuated by the deposition of thin turbidites, and the resultant deposits were thoroughly bioturbated if deposited during normal oxygenation at the sea floor. Periodic benthic dysoxia resulted in the preservation of primary structures, as represented by laminated chalk which consists of thin pelagic laminae alternating with thin turbidites. In addition to the thin turbidites in the laminated chalk, four dif¬ferent turbidite facies are interpreted as representing high- to low-energy flows. Clast-supported chalk conglomerates have previously not been differentiated from other turbidites, but are here interpreted to be directly related to the down-slope evolution of debris flows. Debris flows are rep¬resented by matrix-supported conglomerates, which form one of the most common facies in the succession. High-concentration, gravity-driven suspension flows passed into dilute visco-plastic flows during the final stages of deposition and resulted in the deposition of structureless chalks. Limited shear deformation produced distinct quasi-facies from which the precursor facies can be deduced, whereas intense or continued shear deformation produced a shear-banded quasi-facies from which the precursor facies cannot be deduced in all cases. A series of major slump packages (14–18 in total are interpreted, forming over 40% of the succession; debrites appear to be the most common precursor facies involved in

How burial diagenesis of chalk sediments controls sonic velocity and porosity

DEFF Research Database (Denmark)

Fabricius, Ida Lykke

2003-01-01

Based on P-wave velocity and density data, a new elastic model for chalk sediments is established. The model allows the construction of a series of isoframe (IF) curves, each representing a constant part of the mineral phase contributing to the solid frame. The IF curves can be related to the pro......Based on P-wave velocity and density data, a new elastic model for chalk sediments is established. The model allows the construction of a series of isoframe (IF) curves, each representing a constant part of the mineral phase contributing to the solid frame. The IF curves can be related.......1 or higher. Upon burial, the sediments lose porosity by mechanical compaction, and concurrently, the calcite particles recrystallize into progressively more equant shapes. High compaction rates may keep the particles in relative motion, whereas low compaction rates allow the formation of contact cement...... this process testifies to the absence of chemical compaction by calcite-calcite pressure dissolution, as well as to the porosity-preserving effect of contact cementation. At sufficient burial stress, the presence of stylolites indicates that pressure dissolution takes place between calcite., and silicates...

Nuclear structure studies in highly neutron-deficient (114,116)Xe

Science.gov (United States)

Degraaf, James Hendrick

Lifetimes of nuclear states in 114Xe and 116Xe were measured for the first time; these nuclei represent the most neutron-deficient isotopes of xenon for which lifetimes have now been measured. The fusion-evaporation reactions 58Ni(60Ni, 2p)116Xe at 223 MeV beam energy and 58Ni(58Ni, 2p)114Xe at 215 MeV beam energy were used. Lifetimes were measured using the Recoil Distance Method (RDM) with the 8π gamma-ray spectrometer at Chalk River Laboratories. The new measurements of the B(E2;2+/to 0+) strength in these nuclei, coupled with the recent measurements for heavier xenon isotopes, are well described within the framework of the O(6) symmetry limit of the Interacting Boson Approximation. The octupole nature of the negative parity side-band was also studied, and the lifetime measurements indicate a change from a K/approx 3 structure in heavier xenon isotopes to a K/approx 0,/ 1 structure in 114Xe.

Quick, Easy, and Economic Mineralogical Studies of Flooded Chalk for EOR Experiments Using Raman Spectroscopy

Directory of Open Access Journals (Sweden)

Laura Borromeo

2018-05-01

Full Text Available Understanding the chalk-fluid interactions and the associated mineralogical and mechanical alterations on a sub-micron scale are major goals in Enhanced Oil Recovery. Mechanical strength, porosity, and permeability of chalk are linked to mineral dissolution that occurs during brine injections, and affect the reservoir potential. This paper presents a novel “single grain” methodology to recognize the varieties of carbonates in rocks and loose sediments: Raman spectroscopy is a non-destructive, quick, and user-friendly technique representing a powerful tool to identify minerals down to 1 µm. An innovative working technique for oil exploration is proposed, as the mineralogy of micron-sized crystals grown in two flooded chalk samples (Liége, Belgium was successfully investigated by Raman spectroscopy. The drilled chalk cores were flooded with MgCl2 for ca. 1.5 (Long Term Test and 3 years (Ultra Long Term Test under North Sea reservoir conditions (Long Term Test: 130 °C, 1 PV/day, 9.3 MPa effective stress; Ultra Long Term Test: 130 °C, varying between 1–3 PV/day, 10.4 MPa effective stress. Raman spectroscopy was able to identify the presence of recrystallized magnesite along the core of the Long Term Test up to 4 cm from the injection surface, down to the crystal size of 1–2 µm. In the Ultra Long Term Test core, the growth of MgCO3 affected nearly the entire core (7 cm. In both samples, no dolomite or high-magnesium calcite secondary growth could be detected when analysing 557 and 90 Raman spectra on the Long and Ultra Long Term Test, respectively. This study can offer Raman spectroscopy as a breakthrough tool in petroleum exploration of unconventional reservoirs, due to its quickness, spatial resolution, and non-destructive acquisition of data. These characteristics would encourage its use coupled with electron microscopes and energy dispersive systems or even electron microprobe studies.

Principle and methodology of nuclear power plant site selection. Application to radiocobalt cycle in the Rhone river

International Nuclear Information System (INIS)

Georges, J.

1987-01-01

In a first bibliographic part, after some generalities on radioactivity and nuclear power, general principles of radiation protection and national and international regulations are presented. The methodology of the radioecological study involved in site selection is developed. In a second more experimental part, the processing of radiocobalt gamma radioactivity measurement in water, fishes, plants and Rhone river sediments demonstrates the influence of age and geographical situation of the nuclear power stations located along the river. A laboratory experiment of cobalt 60 transfer from chironomes larvae to carp is carried out. Comparison with the results of other laboratory experiments makes it possible to propose an experimental model of cobalt transfer within a fresh water ecosystem; radioactivity levels calculated for various compartments seem to be consistent with the Rhone river levels [fr

Savannah River Plant's Accountability Inventory Management System (AIMS) (Nuclear materials inventory control)

International Nuclear Information System (INIS)

Croom, R.G.

1976-06-01

The Accountability Inventory Management System (AIMS) is a new computer inventory control system for nuclear materials at the Savannah River Plant, Aiken, South Carolina. The system has two major components, inventory files and system parameter files. AIMS, part of the overall safeguards program, maintains an up-to-date record of nuclear material by location, produces reports required by ERDA in addition to onplant reports, and is capable of a wide range of response to changing input/output requirements through use of user-prepared parameter cards, as opposed to basic system reprogramming

Protective clothing use at the Savannah River Plant Nuclear Facility

International Nuclear Information System (INIS)

Cabbil, C.C.

1987-01-01

The mission of the Savannah River Plant in producing nuclear materials does pose some unique protective clothing and equipment requirements not usually seen in the general industry. In addition to protection from the chemicals and physical agents encountered, radioactive hazards must also be managed. This paper describes the protective clothing and respiratory protection used at SRP, and focuses particularly on the development of a new plastic suit. 5 refs., 7 figs., 3 tabs

Assessing the contribution of the main aquifer of Loire basin to the river discharge during low flow

International Nuclear Information System (INIS)

Monteil, C.

2011-01-01

The evolution of the Loire river low flows is a key issue for various uses such as water supply, irrigation or industrial needs. Power production is a major activity in the Loire basin with four nuclear power plants using the river water for the cooling system. To estimate the evolution of long term in-stream low flow distribution, it is necessary to have a good estimate of the contribution of a complex aquifer system to the river discharge. Three main overlaying aquifer units covering an area of 38000 km 2 are considered: Beauce Limestones (Oligocene), Chalks (Seno-Turonian) and Sands (Cenomanian). A distributed hydrogeological model (Eau-Dyssee) is implemented with the coupling of five modules: surface water budget, watershed routing, river routing, unsaturated zone transfer, and groundwater flow. The model is calibrated over a 10-yr period, validated over another 10-yr period, and then a test simulation is run over 35 years. A hybrid fitting methodology, based on an automated inverse method and a trial-error one, has been developed for the fitting of the Beauce aquifer unit. The other units are calibrated by trial and error. The fitted model simulates properly both discharges and piezometric heads over the whole domain, with a global RMSE between simulated and observed piezometric heads of 2.86 m, and all Nash efficiency at the Loire discharge gauging stations over 0.9. The fitted model has then been used to quantify the hydro-system mass balance at different time scales. Mean aquifer contribution to Loire river discharge during low flow between 1975 and 2008 is estimated at 15 m 3 /s. First results of simulations under four different climate change projections indicate an averaged decrease of these contributions reaching 8 to 50% in 2100. (author)

Mechanical and chemical processes affecting the chalk during burial, insights from combined reflection seismics, well data and field work

DEFF Research Database (Denmark)

Moreau, Julien; Boussaha, Myriam; Thibault, Nicolas Rudolph

2014-01-01

and cores analyses, respectively.However, few sites allow to combine all the different scale of observation for chalk diagenesis. Onshore and offshore high resolution seismics, two fully cored >350 m wells with wireline logging tools and very high quality exposures from a coastal cliff and a quarry form...... works have been performed with astronomical calibration based on stable isotope stratigraphy, wireline logs as well as several palaeontological proxies and detailed sedimentological analysis. Since a couple of decades, a specific kind of fractures has been described in the Chalk of Denmark, the so...

Nuclear power : exploding the myths

International Nuclear Information System (INIS)

Edwards, G.

2001-01-01

A critique of the Canadian government's unaccountability in terms of nuclear decisions was presented. The federal government has spent more than $13 billion building dozens of nuclear facilities, and spreading Canadian nuclear technology to India, Pakistan, Taiwan, Korea, Argentina and Romania. The author argued that this was done without any public consultation or public debate. In addition, the federal government announced in 1996 that it will play a role in nuclear disarmament and would accept tonnes of leftover plutonium from dismantled nuclear warheads to be used as fuel in CANDU reactors. Samples of weapons plutonium fuels from Russia and the United States are currently being tested in a reactor at Chalk River, Ontario. In addition, China received a $1.5 billion loan from the Treasury of Canada to help finance a CANDU reactor. It was the largest loan in Canadian history, yet had no procedure to obtain taxpayer's permission. Turkey was promised an equal amount if it would build a CANDU reactor. Despite this activity, the nuclear industry is in a dying state. No reactors have been ordered in North America for the past 25 years and there are no future prospects. Nuclear expansion has also ground to a halt in western Europe, Germany, Sweden, Switzerland and France. The author discussed the association of nuclear energy with nuclear weapons and dispelled the myth that the nuclear energy programs have nothing to do with nuclear weapons. He also dispelled the myth that plutonium extracted from dismantled warheads can be destroyed by burning it as fuel in civilian reactors. The author emphasized that nuclear warheads are rendered useless when their plutonium cores are removed, but there is no method for destroying the plutonium, which constitutes a serious danger. The third myth which he dispelled was that nuclear power can significantly reduce greenhouse gas emissions. Studies show that each dollar invested in energy efficiency saves 5 to 7 times as much carbon

Design basis for creep of zirconium alloy components in a fast neutron flux

International Nuclear Information System (INIS)

Ross-Ross, P.A.; Fidleris, V.

1975-01-01

The chalk River Nuclear Laboratory's experience with the creep of zirconium alloys in a neutron flux is described. Fast neutron flux changes the creep behaviour of zirconium alloys and new design criteria for in-reactor applications are needed. From experimental results empirical relations describing the effects of neutron flux, stress, temperature, time and anisotropy on creep rate were established. The relations are applied to the design of pressure tubes. (author)

Design basis for creep of zirconium alloy components in a fast neutron flux

International Nuclear Information System (INIS)

Ross-Ross, P.A.; Fidleris, V.

1974-01-01

The Chalk River Nuclear Laboratory's experience with the creep of zirconium alloys in a neutron flux is described. Fast neutron flux changes the creep behavior of zirconium alloys and new design criteria for in-reactor applications are needed. From experimental results empirical relations describing the effects of neutron flux, stress, temperature, time, and anisotropy on creep rate were established. The relations are applied to the design of pressure tubes. (author)

Future Scientific Opportunities At Jefferson Lab

International Nuclear Information System (INIS)

Thomas, Anthony

2007-01-01

Nuclear physics requires at least one major facility world-wide which is capable of fully exploiting the properties of the electro-weak force to investigate precisely the structure of strongly interacting systems. At its current maximum energy of 6 GeV Jefferson Lab has provided a wealth of important information on the structure of nucleons and nuclei. However, the plans to double the energy over the next seven years promise to open new frontiers in nuclear and particle physics. We briefly describe the plans for the 12 GeV Upgrade and the associated physics opportunities.

TASCC newsletter volume 10 no. 1

International Nuclear Information System (INIS)

Thomson, L.

1996-01-01

A newsletter produced by Chalk River's Tandem Accelerator Superconducting Cyclotron Facility. Included in this January issue of TASCC is an update of the facility, letters of support to the government for research to continue at Chalk River Laboratories, home page on the Internet, collaboration on Vsystem with the Hahn-Meitner Institute and a listing of January's experiments. 1 fig

History repeats: a personal reminiscence

Energy Technology Data Exchange (ETDEWEB)

Rogers, J.T. [AECL Board of Directors, R and D Advisory Panel (Canada); Carleton Univ., Dept. of Mechanical and Aerospace Engineering, Ottawa, Ontario (Canada)

2011-09-15

The decision of the federal government to split Atomic Energy of Canada Ltd. into a privately owned CANDU technology company and a publicly owned Nuclear Laboratory has resulted in the purchase by SNC-Lavalin of the AECL's Sheridan Park operations, now called Candu Energy, and the reorganization of Chalk River operations as a national Nuclear Laboratory. This is the third time in my experience in the nuclear field in Canada that a successful nuclear organization with which I have been associated has been significantly disrupted by forces or circumstances outside its control. The other two experiences are briefly described in the article. (author)

Elasticity and electrical resistivity of chalk and greensand during water flooding with selective ions

DEFF Research Database (Denmark)

Katika, Konstantina; Alam, Mohammad Monzurul; Alexeev, Artem

2018-01-01

is water-wet after flooding. Greensand remained mixed wet throughout the experiments. Electrical resistivity data are in agreement with this interpretation. The electrical resistivity data during flooding revealed that the formation brine is not fully replaced by the injected water in both chalk......Water flooding with selective ions has in some cases lead to increased oil recovery. We investigate the physical processes on a pore scale that are responsible for changes in petrophysical and mechanical properties of four oil-bearing chalk and four oil-bearing greensand samples caused by flooding...... with brines containing varying amounts of dissolved NaCl, Na2SO4, MgCl2 and MgSO4. Ultrasonic P-wave velocity and AC resistivity measurements were performed prior to, during and after flow through experiments in order to identify and quantify the processes related to water flooding with selective ions. Low...

Origin of channel systems in the Upper Cretaceous chalk group of the Paris Basin

DEFF Research Database (Denmark)

Esmerode, E. V.; Surlyk, Finn

2009-01-01

the presence of at least two distinct intra-chalk discordant reflections: a Top Santonian and a Mid-Campanian reflection. These reflections are in places associated with up to 120-m-deep channel-like structures trending preferentially N-S and NW-SE. The Mid-Campanian reflection is also sporadically associated...... with a massive secondary dolomite layer, the thicknesses of which may reach 110 m. Diagenesis does not seem to account for the formation of the discordant reflections, as there is neither a one-to-one relationship between the dolomite and discordant reflections, nor are there signs of systematic collapse...... is suggested due to the uninterrupted deep-marine chalk facies below and above both unconformities, and the unrealistically large sea-level drop of more than 200 m, which would be necessary for subaerial exposure of the central Paris Basin during the Campanian. The channels are oriented parallel to the margins...

Integrated seismic analysis of the Chalk Group in eastern Denmark—Implications for estimates of maximum palaeo-burial in southwest Scandinavia

DEFF Research Database (Denmark)

Nielsen, Lars; Boldreel, Lars Ole; Hansen, Thomas Mejer

2011-01-01

Group. The sonic velocities are consistent with the overall seismic layering, although they show additional fine-scale layering. Integration of gamma and sonic log with porosity data shows that seismic velocity is sensitive to clay content. In intervals near boundaries of the refraction model, moderate......The origin of the topography of southwest Scandinavia is subject to discussion. Analysis of borehole seismic velocity has formed the basis for interpretation of several hundred metres of Neogene uplift in parts of Denmark.Here, refraction seismic data constrain a 7.5km long P-wave velocity model...... of the Chalk Group below the Stevns peninsula, eastern part of the Danish Basin. The model contains four layers in the ~860m thick Chalk Group with mean velocities of 2.2km/s, 2.4km/s, 3.1km/s, and 3.9–4.3km/s. Sonic and gamma wireline log data from two cored boreholes represent the upper ~450m of the Chalk...

DOE Lab-to-Lab MPC ampersand A workshop for cooperative tasks with Russian institutes: Focus on critical assemblies and item facilities

International Nuclear Information System (INIS)

Bieber, A.M. Jr.; Fishbone, L.G.; Kato, W.Y.; Lazareth, O.W.; Suda, S.C.; Garcia, D.; Haga, R.

1995-01-01

Seventeen Russian scientists and engineers representing five different institutes participated in a Workshop on material control and accounting as part of the US-Russian Lab-to-Lab Cooperative Program in Nuclear Materials Protection, Control, and Accounting (MPC ampersand A). In addition to presentations and discussions, the Workshop included an exercise at Brookhaven National Laboratory (BNL) and demonstrations at the Zero Power Physics Reactor (critical-assembly facility) of Argonne National Laboratory-West (ANL-W). The Workshop particularly emphasized procedures for physical inventory-taking at critical assemblies and item facilities, with associated supporting techniques and methods. By learning these topics and applying the methods and experience at their own institutes, the Russian scientists and engineers will be able to determine and verify nuclear material inventories based on sound procedures, including measurements. This will constitute a significant enhancement to MPC ampersand A at the Russian institutes

Three Online Neutron Beam Experiments Based on the iLab Shared Architecture

Directory of Open Access Journals (Sweden)

Yakov Ostrocsky

2011-02-01

Full Text Available Students at MIT have traditionally executed certain experiments in the containment building of the MIT nuclear reactor as part of courses in Nuclear Engineering and the third year laboratory course for Physics majors. A joint team of faculty and research staff from the MIT Nuclear Reactor Laboratory (MIT-NRL and MIT’s Center for Educational Computing Initiatives have implemented online versions of three classic experiments; (a a determination of MIT reactor coolant temperature through measurement of thermal neutron velocity, (b a demonstration of the DeBroglie relationship of the kinetic energy and momentum of thermal neutrons and study of Bragg diffraction through a single copper crystal at various orientations, and (c a measurement of beam depletion using a variety of shielding filters. These online experiments were implemented using the LabVIEW® virtual instrumentation package and the interactive version of the iLab Shared Architecture (ISA. Initial assessment of the online experiments indicates that they achieve comparable educational outcomes to traditional versions of the labs executed in the reactor containment building.

NucLab Marcoule. A laboratory facility dedicated to support dismantling operations

International Nuclear Information System (INIS)

Dugne, O.; Houssin, A.; Pierre, D.; Bec-Espitalier, L.

2013-06-01

Formerly dedicated to plutonium production support, NucLab was renovated to perform a wide range of analyses for dismantling, plant operation and process development activities mainly on Marcoule site but also outside (Veurey, Fontenay aux Roses). The Laboratory is under a CEA AREVA partnership as a CEA entity operated by AREVA employees. It provides services to several industrial operators (nuclear process and power plant) in the fields of analytical chemistry, radioactivity measurements, in situ nuclear measurements, decontamination processes and industrial chemistry processes, waste treatments to meet the following analysis requirements. NucLab today is able to support research, production and dismantling activities in all part of dismantling operations. (authors)

Socioeconomic impacts: study of a conceptual nuclear energy center at Green River, Utah

International Nuclear Information System (INIS)

Weaver, R.; Taylor, J.; Burnett, K.; Greenberg, B.

1982-02-01

This document constitutes a segment of a feasibility study investigating the ramifications of constructing a nuclear energy center (NEC) in an arid western region. In this phase of the study, the impacts on socioeconomic conditions in the surrounding communities and possible ways of financing and mitigating these impacts were examined. The general conclusion reached is that the socioeconomic impacts of a nuclear energy center in the Green River area of Southeastern Utah would not impose an absolute bar to NEC development. The economy of the NEC impact area would be substantially transformed by the NEC. In particular, Green River city itself would change from its current status as a relatively stable rural economy with an agricultural, mining, and recreation base to a major city with over 20,000 permanent relatively high income residents. The NEC, by itself, would provide a tax base more than adequate to finance required expansion of public facilities and public human service provisions

Socioeconomic impacts: study of a conceptual nuclear energy center at Green River, Utah

Energy Technology Data Exchange (ETDEWEB)

Weaver, R.; Taylor, J.; Burnett, K.; Greenberg, B.

1982-02-01

This document constitutes a segment of a feasibility study investigating the ramifications of constructing a nuclear energy center (NEC) in an arid western region. In this phase of the study, the impacts on socioeconomic conditions in the surrounding communities and possible ways of financing and mitigating these impacts were examined. The general conclusion reached is that the socioeconomic impacts of a nuclear energy center in the Green River area of Southeastern Utah would not impose an absolute bar to NEC development. The economy of the NEC impact area would be substantially transformed by the NEC. In particular, Green River city itself would change from its current status as a relatively stable rural economy with an agricultural, mining, and recreation base to a major city with over 20,000 permanent relatively high income residents. The NEC, by itself, would provide a tax base more than adequate to finance required expansion of public facilities and public human service provisions.

Savannah River Site FY 1998 Spent Nuclear Fuel Interim Management Plan

International Nuclear Information System (INIS)

Dupont, M.E.

1998-01-01

This document has been prepared to present in one place the near and long-term plans for safe management of Savannah River Site (SRS) spent nuclear fuel inventories until final disposition has been identified and implemented. The activities described are consistent with FY 1998 Annual Operational Plan guidance and with the December 1997 SRS Accelerated Cleanup Plan update. Summarized are highlights, key decision dates, and baseline assumptions of this plan

Nuclear materials facility safety initiative

International Nuclear Information System (INIS)

Peddicord, K.L.; Nelson, P.; Roundhill, M.; Jardine, L.J.; Lazarev, L.; Moshkov, M.; Khromov, V.V.; Kruchkov, E.; Bolyatko, V.; Kazanskij, Yu.; Vorobeva, I.; Lash, T.R.; Newton, D.; Harris, B.

2000-01-01

Safety in any facility in the nuclear fuel cycle is a fundamental goal. However, it is recognized that, for example, should an accident occur in either the U.S. or Russia, the results could seriously delay joint activities to store and disposition weapons fissile materials in both countries. To address this, plans are underway jointly to develop a nuclear materials facility safety initiative. The focus of the initiative would be to share expertise which would lead in improvements in safety and safe practices in the nuclear fuel cycle.The program has two components. The first is a lab-to-lab initiative. The second involves university-to-university collaboration.The lab-to-lab and university-to-university programs will contribute to increased safety in facilities dealing with nuclear materials and related processes. These programs will support important bilateral initiatives, develop the next generation of scientists and engineers which will deal with these challenges, and foster the development of a safety culture

The target vacuum storage facility at iThemba LABS

Science.gov (United States)

Neveling, R.; Kheswa, N. Y.; Papka, P.

2018-05-01

A number of nuclear physics experiments at iThemba LABS require target foils that consist of specific isotopes of elements which are reactive in air. Not only is it important to prepare these targets in a suitable environment to prevent oxidation, but consideration should also be given to the long term storage and handling facilities of such targets. The target vacuum storage facility at iThemba LABS, as well as additional hardware necessary to transport and install the target foils in the experimental chamber, will be discussed.

Fluid substitution studies for North Sea chalk logging data

DEFF Research Database (Denmark)

Gommesen, Lars; Mavko, G.; Mukerji, T.

2002-01-01

We have tested the application of respectively the Kuster-Toksöz and the Gassmann theory as a tool for predicting pore fluid from the elastic properties of brine-saturated North Sea reservoir chalk. We confirm that the Kuster-Toksöz model predicts a larger fluid effect thant the Gassmann model......, and show that the Kuster-Toksöz model fails to predict the presence of hydrocarbons. The Gassmann prediction for the near and potentially invaded zone corresponds more closely to logging data, than the Gassmann prediction for the far, virgin zone. We hereby conclude that the Gassmann theory predicts...

Sedimentology of the Upper Maastrichtian chalk, Danish Central Graben. M-10X (Dan Field), E-5X (Tyra SE Field) facies and core logs

Energy Technology Data Exchange (ETDEWEB)

Ineson, J.R.

2004-07-01

Based on detailed logs presented here at 1:10, the cored Upper Maastrichtian succession of the M-10X (Dan Field) and E-5X (Tyra SE Field) wells in the southern Danish Central Graben is subdivided into eight lithofacies and five ichnofabrics. The dominant bioturbated or laminated chalk mudstones and subordinate sparse skeletal wackestones are largely the result of pelagic carbonate production, sedimented by suspension settling and small volume, low density turbidity currents. Evidence of winnowing/reduced sedimentation rates is yielded by rare incipient hardgrounds; a well-developed mature hardground profile is developed at the Cretaceous-Danian boundary (the ''Maastrichtian hardground''). Rare marl laminae are recorded and a discrete marly chalk bed associated with an interval of finegrained skeletal chalk wackestones near the top of the Maastrichtian is recognised in both wells. Comparison between the two wells demonstrates that the m-scale laminated-bioturbated chalk cycles described from the Dan Field area are both stratigraphically and areally restricted; this has implications for both cyclostratigraphic correlation and reconstruction of depositional environments and Late Maastrichtian evolution of the Danish Central Graben. (au)

A review of HTO evaporation studies at Chalk River Nuclear Laboratories

International Nuclear Information System (INIS)

Brown, R.M.; Barry, P.J.

1979-01-01

Results of the tritium evaporation and exchange studies on Perch Lake are discussed. A model is used to describe the tritium distribution in the atmospheric moisture above the lake. The model, however, underestimates the tritium content at heights above 5 m; such a discrepancy is attributed to the characteristics of the wind speed variation with height, by which vertical diffusion proceeds at somewhat greater rate than expected. Therefore, to represent the Perch Lake system adequately, a three-layer model is required, incorporating a thin laminar layer at the surface, a growing turbulent internal boundary layer and a third layer with high eddy diffusivity. Pan experiments have been used to determine the exponent n=(h-epsilon)/(1-h+Δepislon) of the equation describing the change in isotopic composition during evaporation. The agreement between the experimental and the theoretical values is good for high to middle relative humidities, but significant deviations are shown at low humidities. (author)

The nuclear design of the MAPLE-X10 reactor

International Nuclear Information System (INIS)

Heeds, W.; Lebenhaft, J.R.; Lee, A.G.; Carlson, P.A.; McIlvain, H.; Lidstone, R.F.

1995-01-01

AECL is currently building the 10-MW MAPLE-X10 reactor at the Chalk River Laboratories to operate as a dedicated producer of commercial-scale quantities of key medical and industrial radioisotopes and as a demonstration of the MAPLE reactor design. In support of the safety and licensing analyses, static physics calculations have been performed to determine the neutronic performance and safety characteristics of the MAPLE-X10 reactor. This report summarizes results from the static physics calculations for several core conditions prior to commencing radioisotope production. (author)

Study of a conceptual nuclear energy center at Green River, Utah: regional considerations

International Nuclear Information System (INIS)

1982-01-01

This document constitutes one segment of a feasibility study investigating the ramifications of constructing a nuclear energy center in an arid and remote Western region. This phase of the study discusses regional considerations involved in nuclear energy center development at Green River, Utah. Regional support for NEC development is assessed. In addition, possible regulatory constraints to NEC development are identified and analyzed. Possible resource allocation shortages resulting from NEC development are also considered. A comparison with a similar study on NEC development in the Southeastern United States is also included

Lessons learned from designing and commissioning a versatile data acquisiting system for an accelerator development facility

International Nuclear Information System (INIS)

Langlais, C.E.; Watkins, L.M.; Caissie, L.P.; Wachsmann, W.J.; Andison, C.E.

1977-01-01

Achieving reliable operation of digital equipment under extreme noise conditions presents special challenges to system designers. Experience with the design and operation of a data acquisition and control system for an accelerator development facility at the Chalk River Nuclear Laboratories is reviewed. It is concluded that, by adhering to a few rules in developing both the hardware and the software, satisfactory performance can be guaranteed. Methods of producing a reliable design are presented

Quality assurance and quality control procedures in river water radioecological monitoring

International Nuclear Information System (INIS)

Nalbandyan, A.; Stepanyan, A.

2006-01-01

For recent decades the issue of radioactive pollution of environmental components has acquired a global character as a result of nuclear weapon testing, accidents in NPPs, development of nuclear technologies and so on. A study object of this research is river water as it is known to be radionuclide transport and accumulation mediums and radioactive elements in river water are available as radioactive salts and mechanic and biological pollutants. Moreover, river water is widely used for various economic and commercial purposes and serves a drinking water supply source as well. The ongoing research is performed in the frame of a NATO/OSCE project 'South Caucasus River Monitoring'. The topicality of the problem dictates a necessity of getting credible and compatible results. For adequate radioactive pollution assessment, decisive are the application and keeping standard QA/QC procedures at all the stages of radioecological monitoring. In our research we apply the following ISO standard-based QA/QC procedures: sampling (emphasizing sample identification: sample collection site, date and method), sample transportation (keeping sample conservation and storing requirements), sample treatment and preparation in the lab, radiometric measurements of samples with regard for the time that past from sampling moment to analysis, control and calibration of analytic instruments, control analysis of samples. The obtained data are processed through standard statistic methods of QC to check measurement errors. Gamma-spectrometric measurements are maid using a Genie-2000 (Canberra) software that includes a separate program for measurement QC. The ultimate outcomes are arranged in special protocols (analysis and sampling tasks protocols, sampling task form, field measurement protocol, sample chain of custody form, sample analysis protocol) and compiled in appropriate databases

Qualification of Programmable Electronic System (PES) equipment based on international nuclear I and C standards

International Nuclear Information System (INIS)

De Grosbois, J.; Hepburn, G. A.; Olmstead, R.; Goble, W.; Kumar, V.

2006-01-01

Nuclear power plants (NPPs) are increasingly faced with the challenge of qualifying procured equipment, sub-components, and systems that contain digital programmed electronics for use in safety-related applications. Referred to as a 'programmable electronic system' (PES), such equipment typically contains both complex logic that is vulnerable to systematic design faults, and low voltage electronics hardware that is subject to random faults. Procured PES products or components are often only commercial grade, yet can offer reliable cost effective alternatives to custom-designed or nuclear qualified equipment, provided they can be shown to meet the quality assurance, functional safety, environmental, and reliability requirements of a particular application. The process of confirming this is referred to as application-specific product qualification (ASPQ) and can be challenging and costly. This paper provides an overview of an approach that has been developed at Atomic Energy Canada Limited (AECL) and successfully applied to PES equipment intended for use in domestic Candu R 6 nuclear power plants and special purpose reactors at Chalk River Laboratories. The approach has evolved over the past decade and has recently been adapted to be consistent with, and take advantage of new standards that are applicable to nuclear safety-related I and C systems. Also discussed are how recognized third-party safety-certifications of PES equipment to International Electrotechnical Commission (IEC) standards, and the assessment methods employed, may be used to reduce ASPQ effort. (authors)

International Intercomparison Exercise for Nuclear Accident Dosimetry at the DAF Using GODIVA-IV

Energy Technology Data Exchange (ETDEWEB)

Hickman, David [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hudson, Becka [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2016-12-15

The Nuclear Criticality Safety Program operated under the direction of Dr. Jerry McKamy completed the first NNSA Nuclear Accident Dosimetry exercise on May 27, 2016. Participants in the exercise were from Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Sandia National Laboratory (SNL), Savanah River Site (SRS), Pacific Northwest National Laboratory (PNNL), US Navy, the Atomic Weapons Establishment (United Kingdom) under the auspices of JOWOG 30, and the Institute for Radiological Protection and Nuclear Safety (France) by special invitation and NCSP memorandum of understanding. This exercise was the culmination of a series of Integral Experiment Requests (IER) that included the establishment of the Nuclear Criticality Experimental Research Center, (NCERC) the startup of the Godiva Reactor (IER-194), the establishment of a the Nuclear Accident Dosimetry Laboratory (NAD LAB) in Mercury, NV, and the determination of reference dosimetry values for the mixed neutron and photon radiation field of Godiva within NCERC.

Using Raman spectroscopic imaging for non-destructive analysis of filler distribution in chalk filled polypropylene

DEFF Research Database (Denmark)

Boros, Evelin; Porse, Peter Bak; Nielsen, Inga

2016-01-01

A feasibility study on using Raman spectral imaging for visualization and analysis of filler distribution in chalk filled poly-propylene samples has been carried out. The spectral images were acquired using a Raman spectrometer with 785 nm light source.Eight injection-molded samples with concentr...

Results of detailed ground geophysical surveys for locating and differentiating waste structures in waste management area 'A' at Chalk River Laboratories, Ontario

Energy Technology Data Exchange (ETDEWEB)

Tomsons, D.K.; Street, P.J.; Lodha, G.S

1999-07-01

Waste Management Area 'A' (WMA 'A'), located in the outer area of the Chalk River Laboratories (CRL) was in use as a waste burial site from 1946 to 1955. Waste management structures include debris-filled trenches, concrete bunkers and miscellaneous contaminated solid materials, and ditches and pits used for liquid dispersal. In order to update historical records, it was proposed to conduct detailed ground geophysical surveys to define the locations of waste management structures in WMA 'A', assist in planning of the drilling and sampling program to provide ground truth for the geophysics investigation and to predict the nature and locations of unknown/undefined shallow structures. A detailed ground geophysical survey grid was established with a total of 127 grid lines, oriented NNE and spaced one metre apart. The geophysical surveys were carried out during August and September, 1996. The combination of geophysical tools used included the Geonics EM61 metal detector, the GSM-19 magnetometer/gradiometer and a RAMAC high frequency ground penetrating radar system. The geophysical surveys were successful in identifying waste management structures and in characterizing to some extent, the composition of the waste. The geophysical surveys are able to determine the presence of most of the known waste management structures, especially in the western and central portions of the grid which contain the majority of the metallic waste. The eastern portion of the grid has a completely different geophysical character. While historical records show that trenches were dug, they are far less evident in the geophysical record. There is clear evidence for a trench running between lines 30E and 63E at 70 m. There are indications from the radar survey of other trench-like structures in the eastern portion. EM61 data clearly show that there is far less metallic debris in the eastern portion. The geophysical surveys were also successful in identifying

Aerobic degradation potential of the herbicides mecoprop, dichlorprop and bentazone in groundwater from chalk aquifers

DEFF Research Database (Denmark)

Levi, Suzi; Hybel, Anne-Marie; Bjerg, Poul Løgstrup

2011-01-01

The aerobic degradation potential of mecoprop, dichlorprop and bentazone was studied at concentration of 1 μg/L in laboratory batch experiments with groundwater from chalk aquifers. Within the incubation period of 129 days, 14C-mecoprop concentration decreased to 60-80% in the microcosms with gro...

Release and transport of artificial radionuclides from nuclear weapons related activities in the Ob River, Siberia over the course of the nuclear age

International Nuclear Information System (INIS)

Sayles, F.L.; Kenna, T.C.; Livingston, H.D.

1999-01-01

Studies of sediment cores from lakes on the flood plain of the Ob River, Siberia have been used to develop a history of the release, transport, and deposition of artificial radionuclides related to the development and testing of nuclear weapons over the duration of the nuclear age (∼1950 to the present) in this major Arctic river system. The Ob is of particular importance in this regard as two of the former Soviet Union's major weapons production plants, Mayak and Tomsk-7, and the Semipalatinsk test site are located within the Ob drainage basin. Accidents and intentional releases of radionuclides at both plants have been substantial, raising the issue of transport throughout this extensive river system as well as delivery to the Arctic Ocean. Our studies have included determining sediment profiles of 239,240 Pu, 137 Cs, and the natural nuclide 210 Pb and its parent 226 Ra in a number of cores from the Ob delta, as well as analysis of 239 Pu, 240 Pu, and 237 Np. The latter provide sensitive measures of the presence of non-fallout materials derived from weapons production activities

Web-based, Interactive, Nuclear Reactor Transient Analyzer using LabVIEW and RELAP5 (ATHENA)

International Nuclear Information System (INIS)

Kim, K. D.; Chung, B. D.; Rizwan-uddin

2006-01-01

In nuclear engineering, large system analysis codes such as RELAP5, TRAC-M, etc. play an important role in evaluating a reactor system behavior during a wide range of transient conditions. One limitation that restricts their use on a wider scale is that these codes often have a complicated I/O structure. This has motivated the development of GUI tools for best estimate codes, such as SNAP and ViSA, etc. In addition to a user interface, a greater degree of freedom in simulation and analyses of nuclear transient phenomena can be achieved if computer codes and their outputs are accessible from anywhere through the web. Such a web-based interactive interface can be very useful for geographically distributed groups when there is a need to share real-time data. Using mostly off-the-shelf technology, such a capability - a web-based transient analyzer based on a best-estimate code - has been developed. Specifically, the widely used best-estimate code RELAP5 is linked with a graphical interface. Moreover, a capability to web-cast is also available. This has been achieved by using the LabVIEW virtual instruments (VIs). In addition to the graphical display of the results, interactive control functions have also been added that allow operator's actions as well as, if permitted, by a distant user through the web

First commissioning results with the Grenoble test electron cyclotron resonance ion source at iThemba LABS

Energy Technology Data Exchange (ETDEWEB)

Thomae, R.; Conradie, J.; Delsink, H.; Du Plessis, H.; Fourie, D.; Klopp, M.; Kohler, I.; Lussi, C.; McAlister, R.; Ntshangase, S.; Sakildien, M. [iThemba LABS, P.O Box 722, Somerset West 7130 (South Africa); Hitz, D. [CEA/DRFMC, 17 Av. Des Martyrs, 38054, Grenoble Cedex 9 (France); Kuechler, D. [CERN, BE/ABP/HSL, 1211 Geneva 23 (Switzerland)

2012-02-15

iThemba Laboratory for Accelerator Based Science (iThemba LABS) is a multi-disciplinary accelerator facility. One of its main activities is the operation of a separated-sector cyclotron with a K-value of 200, which provides beams of various ion species. These beams are used for fundamental nuclear physics research in the intermediate energy region, radioisotope production, and medical physics applications. Due to the requirements of nuclear physics for new ion species and higher energies, the decision was made to install a copy of the so-called Grenoble test source (GTS) at iThemba LABS. In this paper, we will report on the experimental setup and the first results obtained with the GTS2 at iThemba LABS.

First commissioning results with the Grenoble test electron cyclotron resonance ion source at iThemba LABS

International Nuclear Information System (INIS)

Thomae, R.; Conradie, J.; Delsink, H.; Du Plessis, H.; Fourie, D.; Klopp, M.; Kohler, I.; Lussi, C.; McAlister, R.; Ntshangase, S.; Sakildien, M.; Hitz, D.; Kuechler, D.

2012-01-01

iThemba Laboratory for Accelerator Based Science (iThemba LABS) is a multi-disciplinary accelerator facility. One of its main activities is the operation of a separated-sector cyclotron with a K-value of 200, which provides beams of various ion species. These beams are used for fundamental nuclear physics research in the intermediate energy region, radioisotope production, and medical physics applications. Due to the requirements of nuclear physics for new ion species and higher energies, the decision was made to install a copy of the so-called Grenoble test source (GTS) at iThemba LABS. In this paper, we will report on the experimental setup and the first results obtained with the GTS2 at iThemba LABS.

A high-speed data acquisition system to measure low-level current from self-powered flux detectors in CANDU nuclear reactors

International Nuclear Information System (INIS)

Lawrence, C.B.; Hall, D.S.

1982-05-01

Self-powered flux detectors are used in CANDU nuclear power reactors to determine the spatial neutron flux distribution in the reactor core for use by both the reactor control and safety systems. To establish the dynamic response of different types of flux detectors, the Chalk River Nuclear Laboratories have an ongoing experimental irradiation program in the NRU research reactor for which a data acquistion system has been developed. The system described in this paper is used to measure the currents from the detectors both at a slow, regular logging interval, and at a rapid, adaptive rate following a reactor shutdown. Currents that range from 100 pA to 1 mA full scale can be measured from up to 38 detectors and stored at sampling rates of up to 20 samples per second. The dynamic characteristics of the detectors can be computed from the stored records. The data acquisition system comprises a DEC LSI-11/23 microcomputer, dual cartridge disks, floppy disks, a hard copy and a video display terminal. The RT-11 operating system is used and all application programs are written in FORTRAN

Guidelines for random excitation forces due to cross flow in steam generators

Energy Technology Data Exchange (ETDEWEB)

Taylor, C.E.; Pettigrew, M.J. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

1998-07-01

Random excitation forces can cause low-amplitude tube motion that will result in long-term fretting-wear or fatigue. To prevent these tube failures in steam generators and other heat exchangers, designers and trouble-shooters must have guidelines that incorporate random or turbulent fluid forces. Experiments designed to measure fluid forces have been carried out at Chalk River Laboratories and at other labs around the world. The data from these experiments have been studied and collated to determine suitable guidelines for random excitation forces. In this paper, a guideline for random excitation forces in single-phase cross flow is presented in the form of normalised spectra that are applicable to a wide range of flow conditions and tube frequencies. In particular, the experimental results used in this study were carried out over the full range of flow conditions found in a nuclear steam generator. The proposed guidelines are applicable to steam generators, condensers, reheaters and other shell-and-tube heat exchangers. They may be used for flow-induced vibration analysis of new or existing components, as input to vibration analysis computer codes and as specifications in procurement documents. (author)

Guidelines for random excitation forces due to cross flow in steam generators

International Nuclear Information System (INIS)

Taylor, C.E.; Pettigrew, M.J.

1998-01-01

Random excitation forces can cause low-amplitude tube motion that will result in long-term fretting-wear or fatigue. To prevent these tube failures in steam generators and other heat exchangers, designers and trouble-shooters must have guidelines that incorporate random or turbulent fluid forces. Experiments designed to measure fluid forces have been carried out at Chalk River Laboratories and at other labs around the world. The data from these experiments have been studied and collated to determine suitable guidelines for random excitation forces. In this paper, a guideline for random excitation forces in single-phase cross flow is presented in the form of normalised spectra that are applicable to a wide range of flow conditions and tube frequencies. In particular, the experimental results used in this study were carried out over the full range of flow conditions found in a nuclear steam generator. The proposed guidelines are applicable to steam generators, condensers, reheaters and other shell-and-tube heat exchangers. They may be used for flow-induced vibration analysis of new or existing components, as input to vibration analysis computer codes and as specifications in procurement documents. (author)

Flux distribution measurements in the Bruce B Unit 6 reactor using a transportable traveling flux detector system

International Nuclear Information System (INIS)

Leung, T.C.; Drewell, N.H.; Hall, D.S.; Lopez, A.M.

1987-01-01

A transportable traveling flux detector (TFD) system for use in power reactors has been developed and tested at Chalk River Nuclear Labs. in Canada. It consists of a miniature fission chamber, a motor drive mechanism, a computerized control unit, and a data acquisition subsystem. The TFD system was initially designed for the in situ calibration of fixed self-powered detectors in operating power reactors and for flux measurements to verify reactor physics calculations. However, this system can also be used as a general diagnostic tool for the investigation of apparent detector failures and flux anomalies and to determine the movement of reactor internal components. This paper describes the first successful use of the computerized TFD system in an operating Canada deuterium uranium (CANDU) power reactor and the results obtained from the flux distribution measurements. An attempt is made to correlate minima in the flux profile with the locations of fuel channels so that future measurements can be used to determine the sag of the channels. Twenty-seven in-core flux detector assemblies in the 855-MW (electric) Unit 6 reactor of the Ontario Hydro Bruce B Generating Station were scanned

Full-Length High-Temperature Severe Fuel Damage Test No. 5: Final safety analysis

International Nuclear Information System (INIS)

Lanning, D.D.; Lombardo, N.J.; Panisko, F.E.

1993-09-01

This report presents the final safety analysis for the preparation, conduct, and post-test discharge operation for the Full-Length High Temperature Experiment-5 (FLHT-5) to be conducted in the L-24 position of the National Research Universal (NRU) Reactor at Chalk River Nuclear Laboratories (CRNL), Ontario, Canada. The test is sponsored by an international group organized by the US Nuclear Regulatory Commission. The test is designed and conducted by staff from Pacific Northwest Laboratory with CRNL staff support. The test will study the consequences of loss-of-coolant and the progression of severe fuel damage

TASCC newsletter volume 7 no. 2

International Nuclear Information System (INIS)

Thomson, L.

1993-02-01

A newsletter produced by Chalk River's Tandem Accelerator Superconducting Cyclotron Facility. Included in this February issue are notices on upcoming visits to TASCC by the Nuclear and Particle Physics Advisory Panel and a visit by the Deputy Minister of Industry, Science and Technology. The future of TASCC employees being of concern, a notice of terminations at AECL, none yet to TASCC. A facility report and the operating record plus a listing of experiments conducted in February

Trace element content of precipitation in a remote area

International Nuclear Information System (INIS)

Merritt, W.F.

1976-01-01

Rain and snow, sampled over a period of 18 months at Chalk River Nuclear Laboratories, were analysed for 40 elements by thermal neutron activation analysis. Correlation analysis revealed that the elements detected could be divided into groups of similar behaviour. Storm tracks for the events sampled were obtained, but only generalizations as to the probable origin of the trace elements could be made. Deuterium content of the samples was not correlated with levels of trace elements. (author)

Water movements in the unsaturated zone and recharge of the aquifer in the Champagne Chalk (France): Isotopic and chemical approaches

International Nuclear Information System (INIS)

Vachier, P.; Dever, L.; Fontes, J.C.

1987-01-01

Water from the unsaturated zone in the chalk, obtained from porous plugs, was subjected to chemical and isotope analyses over a three-year period. Tensiometric and volumetric water content measurements were carried out at the same time. The results obtained make it possible to establish an outline of the hydrodynamics of this porous, fissured chalk medium. Matrix porosity was 0.42 while fissure porosity was in the region of 0.01. The tritium and nitrate concentrations in the water fix the mean residence time in the 20-metre unsaturated zone at about 30 years. The isotope profiles ( 18 O and 3 H) and their downward displacements make it possible to estimate the mean annual recharge into the unconfined groundwater in the chalk (200 to 300 mm, depending on plant cover). The vertical movement of the solution in the porous matrix is dominated by the piston effect. Variations in 18 O concentration can be correlated with local climatic fluctuations. The recharge period runs from November to March, with summer rainfall playing no part. A comparison of 2 H and 18 O concentrations shows that even winter rainfall is partially removed by evaporation. (author). 17 refs, 11 figs, 1 tab

Investigation of spore forming bacterial flooding for enhanced oil recovery in a North Sea chalk Reservoir

DEFF Research Database (Denmark)

Halim, Amalia Yunita; Nielsen, Sidsel Marie; Eliasson Lantz, Anna

2015-01-01

Little has been done to study microbial enhanced oil recovery (MEOR) in chalk reservoirs. The present study focuses on core flooding experiments designed to see microbial plugging and its effect on oil recovery. A pressure tapped core holder was used for this purpose. A spore forming bacteria...... Bacillus licheniformis 421 was used as it was shown to be a good candidate in a previous study. Bacterial spore can penetrate deeper into the chalk rock, squeezing through the pore throats. Our results showed that injection of B. licheniformis 421 as a tertiary oil recovery method, in the residual oil...... saturation state, was able to produce additionally 1.0-2.3% original oil in place (OOIP) in homogeneous cores and 6.9-8.8% OOIP in heterogeneous cores. In addition, the pressure gradient was much higher in the heterogeneous cores, which confirms that bacterial selective plugging plays an important role...

COMPARISON OF THE TRADITIONAL CHALK AND BOARD LECTURE SYSTEM VERSUS POWER POINT PRESENTATION AS A TEACHING TECHNIQUE FOR TEACHING GROSS ANATOMY TO THE FIRST PROFESSIONAL MEDICAL STUDENTS

OpenAIRE

Nusrat; Abdul

2015-01-01

Traditionally and conventionally, gross anatomy is taught by lectures and cadaveric dissection and the lectures are taken with chalk and board (C&B) or chalk and talk method in, India. But there is always a debate over the most effective method of lecture delivery. AIM : The aim of this study was to compare the role and effecti...

Estimation of groundwater recharge to chalk and sandstone aquifers using simple soil models

Science.gov (United States)

Ragab, R.; Finch, J.; Harding, R.

1997-03-01

On the assumption that the water draining below the root zone is potentially available for groundwater recharge, two current UK methods for estimating annual groundwater recharge have been compared with a new soil model using data from four sites under permanent grass in the UK: two sites representative of the Chalk aquifer at Bridgest Farm (Hampshire) and Fleam Dyke (Cambridgeshire), and two sites on the Triassic sandstone at Bicton College (Devon) and Bacon Hall (Shropshire). A Four Root Layers Model (FRLM), the Penman-Grindley model and the UK Meteorological Office Rainfall and Evaporation Calculation System (MORECS) were used. The new soil model was run with potential evaporation as input both from the MORECS and from the Penman-Monteith equation. The models were run for the Chalk sites both with and without a bypass flow of 15% of rainfall. Bypass was not considered for the sandstone sites. The performance of the models was tested against neutron probes measurements of soil moisture deficits. In addition, the annual groundwater recharge estimated from the models was compared with the published values obtained from the 'zero flux plane' method. Generally, the Penman-Grindley model was more successful in predicting the time for soil to return to its field capacity than in predicting the magnitude of the soil moisture deficit. The annual groundwater recharge was predicted with reasonable accuracy. The MORECS relatively tended to overestimate the soil moisture deficits and to delay the time at which the soil returns to its field capacity. The consequences were underestimates of annual groundwater recharge, owing either to the higher values of potential evaporation calculated from the MORECS or tothe high available water capacity values associated with the soils under consideration. The new soil model (FRLM) predicts the soil moisture deficits successfully and hence is reliable in estimating the annual groundwater recharge. The model is capable of doing this with

A LabVIEW®-based software for the control of the AUTORAD platform. A fully automated multisequential flow injection analysis Lab-on-Valve (MSFIA-LOV) system for radiochemical analysis

International Nuclear Information System (INIS)

Barbesi, Donato; Vilas, Victor Vicente; Millet, Sylvain; Sandow, Miguel; Colle, Jean-Yves; Heras, Laura Aldave de las

2017-01-01

A LabVIEW®-based software for the control of the fully automated multi-sequential flow injection analysis Lab-on-Valve (MSFIA-LOV) platform AutoRAD performing radiochemical analysis is described. The analytical platform interfaces an Arduino®-based device triggering multiple detectors providing a flexible and fit for purpose choice of detection systems. The different analytical devices are interfaced to the PC running LabVIEW®VI software using USB and RS232 interfaces, both for sending commands and receiving confirmation or error responses. The AUTORAD platform has been successfully applied for the chemical separation and determination of Sr, an important fission product pertinent to nuclear waste. (author)

A LabVIEW®-based software for the control of the AUTORAD platform: a fully automated multisequential flow injection analysis Lab-on-Valve (MSFIA-LOV) system for radiochemical analysis.

Science.gov (United States)

Barbesi, Donato; Vicente Vilas, Víctor; Millet, Sylvain; Sandow, Miguel; Colle, Jean-Yves; Aldave de Las Heras, Laura

2017-01-01

A LabVIEW ® -based software for the control of the fully automated multi-sequential flow injection analysis Lab-on-Valve (MSFIA-LOV) platform AutoRAD performing radiochemical analysis is described. The analytical platform interfaces an Arduino ® -based device triggering multiple detectors providing a flexible and fit for purpose choice of detection systems. The different analytical devices are interfaced to the PC running LabVIEW ® VI software using USB and RS232 interfaces, both for sending commands and receiving confirmation or error responses. The AUTORAD platform has been successfully applied for the chemical separation and determination of Sr, an important fission product pertinent to nuclear waste.

Measuring and Modeling the Displacement of Connate Water in Chalk Core Plugs during Water Injection

DEFF Research Database (Denmark)

Korsbech, Uffe C C; Aage, Helle Karina; Andersen, Bertel Lohmann

2006-01-01

and forms a mixed water bank with almost 100% connate water in the front behind which a gradual transition to pure injection water occurs. This result underpins log interpretations from waterflooded chalk reservoirs. An ad hoc model was set up by use of the results, and the process was examined...

Deep saltwater in Chalk of North-West Europe: origin, interface characteristics and development over geological time

DEFF Research Database (Denmark)

Bonnesen, Ellen Prip; Larsen, F.; Sonnenborg, T.O.

2009-01-01

High-concentration saltwaters occur in many places in the regional Chalk aquifers of North-West Europe; to investigate deep occurrences, profiles of interstitial porewater chemistry have been studied from three 250-450m deep cores drilled in the eastern parts of Zealand, Denmark. At the studied...

Savannah River Site Spent Nuclear Fuel Management Final Environmental Impact Statement

Energy Technology Data Exchange (ETDEWEB)

N/A

2000-04-14

The proposed DOE action considered in this environmental impact statement (EIS) is to implement appropriate processes for the safe and efficient management of spent nuclear fuel and targets at the Savannah River Site (SRS) in Aiken County, South Carolina, including placing these materials in forms suitable for ultimate disposition. Options to treat, package, and store this material are discussed. The material included in this EIS consists of approximately 68 metric tons heavy metal (MTHM) of spent nuclear fuel 20 MTHM of aluminum-based spent nuclear fuel at SRS, as much as 28 MTHM of aluminum-clad spent nuclear fuel from foreign and domestic research reactors to be shipped to SRS through 2035, and 20 MTHM of stainless-steel or zirconium-clad spent nuclear fuel and some Americium/Curium Targets stored at SRS. Alternatives considered in this EIS encompass a range of new packaging, new processing, and conventional processing technologies, as well as the No Action Alternative. A preferred alternative is identified in which DOE would prepare about 97% by volume (about 60% by mass) of the aluminum-based fuel for disposition using a melt and dilute treatment process. The remaining 3% by volume (about 40% by mass) would be managed using chemical separation. Impacts are assessed primarily in the areas of water resources, air resources, public and worker health, waste management, socioeconomic, and cumulative impacts.

Clinch River Breeder Reactor Plant: a building block in nuclear technology

International Nuclear Information System (INIS)

McCormack, M.

1979-01-01

Interest in breeder reactors dates from the Manhatten Project to the present effort to build the Clinch River Liquid Metal Fast Breeder Reactor (LMFBR) demonstration plant. Seven breeder-type reactors which were built during this time are described and their technological progress assessed. The Clinch River Breeder Reactor Project (CRBRP) has been designed to demonstrate that it can be licensed, can operate on a large power grid, and can provide industry with important experience. As the next logical step in LMFBR development, the project has suffered repeated cancellation efforts with only minor modifications to its schedule. Controversies have developed over the timing of a large-scale demonstration plant, the risks of proliferation, economics, and other problems. Among the innovative developments adopted for the CRBRP is a higher thermal efficiency potential, the type of development which Senator McCormack feels justifies continuing the project. He argues that the nuclear power program can and should be revitalized by continuing the CRBRP

Clinch River Breeder Reactor Plant: a building block in nuclear technology

Energy Technology Data Exchange (ETDEWEB)

McCormack, M.

1979-01-01

Interest in breeder reactors dates from the Manhatten Project to the present effort to build the Clinch River Liquid Metal Fast Breeder Reactor (LMFBR) demonstration plant. Seven breeder-type reactors which were built during this time are described and their technological progress assessed. The Clinch River Breeder Reactor Project (CRBRP) has been designed to demonstrate that it can be licensed, can operate on a large power grid, and can provide industry with important experience. As the next logical step in LMFBR development, the project has suffered repeated cancellation efforts with only minor modifications to its schedule. Controversies have developed over the timing of a large-scale demonstration plant, the risks of proliferation, economics, and other problems. Among the innovative developments adopted for the CRBRP is a higher thermal efficiency potential, the type of development which Senator McCormack feels justifies continuing the project. He argues that the nuclear power program can and should be revitalized by continuing the CRBRP.

Understanding Fluid Flow during Tectonic Reactivation: An Example from the Flamborough Head Chalk Outcrop (UK

Directory of Open Access Journals (Sweden)

O. Faÿ-Gomord

2018-01-01

Full Text Available Flamborough Head chalks are located at the extremities of E-W and N-S trending fault systems along the Yorkshire coast (UK. Rock deformation is expressed in Selwicks Bay where a normal fault is exposed along with a high density of calcite veins. The fault mineralization is tested using geochemistry. Crosscutting relationships are used to differentiate between three vein generations: a network of parallel veins that are oriented perpendicular to stratigraphy (Group I, hydraulic breccia with typical jigsaw puzzle structure (Group II, and a third generation of calcite veins crosscutting the two previous generations (Group III. Geochemical analyses revealed that all three generations possess the same chemical signature and must reflect successive pulses from the same mineralizing fluid source. Strontium isotope analyses showed that the veins have elevated 87Sr/86Sr ratios, that is, up to 7.110, while ratios of the chalk matrix equal 7.707. The latter value is in agreement with the signature of Late Cretaceous seawater. Consequently, the source of the fluid is external, reflecting an open system. The radiogenic Sr-isotope ratios, combined with low iron concentration, suggest that fluids migrated through sandy deposits. Fluid inclusion salinities range from 0 to 12 eq. wt% NaCl equiv. with a dominance of very low salinity inclusions, reflecting a meteoric signal. This leads to a model where meteoric fluids stored in an underlying confined sandstone aquifer were remobilized. The wide range of salinities could result from mixing of the meteoric fluid with some more saline fluids present in the rock sequence or from the dissolution of salts in the subsurface. In addition to the understanding of the local paragenetic evolution of the veining in Flamborough Head chalks, this study offers an insight into the way how fluid flows and mineralizes along fault zones.

Radiocarbon dispersion around Canadian nuclear facilities

International Nuclear Information System (INIS)

Milton, G.M.; Kramer, S.J.; Brown, R.M.; Repta, C.J.W.; King, K.J.; Rao, R.R.

1995-01-01

Canadian deuterium uranium (CANDU) pressurized heavy-water reactors produce 14 C by neutron activation of trace quantities of nitrogen in annular gas and reactor components ( 14 N(n,p) 14 C), and from 17 O in the heavy water moderator by ( 17 O(n,α) 14 C). The radiocarbon produced in the moderator is removed on ion exchange resins incorporated in the water purification systems; however, a much smaller gaseous portion is vented from reactor stacks at activity levels considerably below 1% of permissible derived emission limits. Early measurements of the carbon speciation indicated that >90% of the 14 C emitted was in the form of CO 2 .We conducted surveys of the atmospheric dispersion of 14 CO 2 at the Chalk River Laboratories and at the Pickering Nuclear Generating Station. We analyzed air, vegetation, soils and tree rings to add to the historical record of 14 C emissions at these sites, and to gain an understanding of the relative importance of the various carbon pools that act as sources/sinks within the total 14 C budget. Better model parameters than those currently available for calculating the dose to the critical group can be obtained in this manner. Global dose estimates may require the development of techniques for estimating emissions occurring outside the growing season. (author)

Law enforcement tools available at the Savannah River Site

Energy Technology Data Exchange (ETDEWEB)

Hofstetter, K.J.

2000-03-29

A number of nuclear technologies developed and applied at the Savannah River Site in support of nuclear weapons material production and environmental remediation can be applied to problems in law enforcement. Techniques and equipment for high-sensitivity analyses of samples are available to identify and quantify trace elements and establish origins and histories of forensic evidence removed from crime scenes. While some of theses capabilities are available at local crime laboratories, state-of-the-art equipment and breakthroughs in analytical techniques are continually being developed at DOE laboratories. Extensive experience with the handling of radioactive samples at the DOE labs minimizes the chances of cross-contamination of evidence received from law enforcement. In addition to high-sensitivity analyses, many of the field techniques developed for use in a nuclear facility can assist law enforcement personnel in detecting illicit materials and operations, in retrieving of pertinent evidence and in surveying crime scenes. Some of these tools include chemical sniffers, hand-held detectors, thermal imaging, etc. In addition, mobile laboratories can be deployed to a crime scene to provide field screening of potential evidence. A variety of portable sensors can be deployed on vehicle, aerial, surface or submersible platforms to assist in the location of pertinent evidence or illicit operations. Several specific nuclear technologies available to law enforcement and their potential uses are discussed.

Law enforcement tools available at the Savannah River Site

International Nuclear Information System (INIS)

Hofstetter, K.J.; Beals, D.M.; Halverson, J.E.; Villa-Aleman, E.; Hayes, D.W.

2001-01-01

A number of nuclear technologies developed and applied at the Savannah River Site in support of nuclear weapons material production and environmental remediation can be applied to problems in law enforcement. Techniques and equipment for high-sensitivity analyses of samples are available to identify and quantify trace elements and establish origins and histories of forensic evidence removed from crime scenes. While some of these capabilities are available at local crime laboratories, state-of-the-art equipment and breakthroughs in analytical techniques are continually being developed at DOE laboratories. Extensive experience with the handling of radioactive samples at the DOE labs minimizes the chances of cross-contamination of evidence received from law enforcement. In addition to high-sensitivity analyses, many of the field techniques developed for use in a nuclear facility can assist law enforcement personnel in detecting illicit materials and operations, in retrieving of pertinent evidence and in surveying crime sciences. Some of these tools include chemical sniffers, hand-held detectors, thermal imaging, etc. In addition, mobile laboratories can be deployed to a crime scene to provide field screening of potential evidence. A variety of portable sensors can be deployed on vehicle, aerial, surface of submersible platforms to assist in the location of pertinent evidence or illicit operations. Several specific nuclear technologies available to law enforcement and their potential uses are discussed. (author)

Frequency spectrum analysis of 252Cf neutron source based on LabVIEW

International Nuclear Information System (INIS)

Mi Deling; Li Pengcheng

2011-01-01

The frequency spectrum analysis of 252 Cf Neutron source is an extremely important method in nuclear stochastic signal processing. Focused on the special '0' and '1' structure of neutron pulse series, this paper proposes a fast-correlation algorithm to improve the computational rate of the spectrum analysis system. And the multi-core processor technology is employed as well as multi-threaded programming techniques of LabVIEW to construct frequency spectrum analysis system of 252 Cf neutron source based on LabVIEW. It not only obtains the auto-correlation and cross correlation results, but also auto-power spectrum,cross-power spectrum and ratio of spectral density. The results show that: analysis tools based on LabVIEW improve the fast auto-correlation and cross correlation code operating efficiency about by 25% to 35%, also verify the feasibility of using LabVIEW for spectrum analysis. (authors)

Application of probabilistic risk assessment to nuclear fuel reprocessing at the Savannah River Plant

International Nuclear Information System (INIS)

Durant, W.S.

1980-01-01

The Savannah River Laboratory has developed an integrated risk assessment methodology that has been applied to systems in the nuclear fuel reprocessing facilities at the Savannah River Plant. The methodology can be applied to several types of design and operational problems. Basically, the analysis is subdivided into individual modules that can be either utilized separately or integrated into an overall risk analysis. Computer codes and computer data banks are utilized extensively to minimize the manual effort. The flow of information begins with a definition of the system to be analyzed followed by an evaluation of sources of fault information, storage of this information in data banks, design analysis and data treatment, risk calculations, and end product options

LABORATORY INVESTIGATIONS OF SILICATE MUD CONTAMINATION WITH CALCIUM

Directory of Open Access Journals (Sweden)

Nediljka Gaurina-Međimurec

2004-12-01

Full Text Available The silicate-based drilling fluid is a low solids KCl/polymer system with the addition of soluble sodium or potassium silicate to enhance inhibition and wellbore stability. Silicate-based drilling fluids exhibit remarkable shale and chalk stabilizing properties, resulting in gauge hole and the formation of firm cuttings when drilling reactive shales and soft chalks. Silicates protect shales by in-situ gellation when exposed to the neutral pore fluid and precipitation, which occurs on contact with divalent ions present at the surface of the shale. Also, silicates prevent the dispersion and washouts when drilling soft chalk by reacting with the Ca2+ ions present on chalk surfaces of cutting and wellbore to form a protective film. The silicate-based drilling fluid can be used during drilling hole section through shale interbeded anhydrite formations because of its superior shale stabilizing characteristics. However, drilling through the anhydrite can decrease the silicate concentration and change rheological and filtration fluid properties. So, the critical concentration of calcium ions should be investigated by lab tests. This paper details the mechanism of shale inhibition using silicate-based drilling fluid, and presents results of lab tests conducted to ascertain the effect of Ca2+ ions on silicate level in the fluid and the fluid properties.

Macrophytes control on a stretch of the Ebro River flowing through the Asco Nuclear Power Plant

International Nuclear Information System (INIS)

Munte Clua, L.; Fernandez Alentorn, E.; Beltran Grau, A.

2010-01-01

The objective of this paper is to evaluate the time evolution of the different macrophytes populations in the stretch of the Ebro River between the town of Flix and the Asco Nuclear Power Plant, and the effects observed by the programmed flood for their control.

Advanced HVAC modeling with FemLab/Simulink/MatLab

NARCIS (Netherlands)

Schijndel, van A.W.M.

2003-01-01

The combined MatLab toolboxes FemLab and Simulink are evaluated as solvers for HVAC problems based on partial differential equations (PDEs). The FemLab software is designed to simulate systems of coupled PDEs, 1-D, 2-D or 3-D, nonlinear and time dependent. In order to show how the program works, a

Linear alkylbenzenes in riverine runoff of the Pearl River Delta (China) and their application as anthropogenic molecular markers in coastal environments

International Nuclear Information System (INIS)

Ni Honggang; Lu Fenghui; Wang Jizhong; Guan Yufeng; Luo Xianlin; Zeng, Eddy Y.

2008-01-01

The average concentrations of ΣLABs (sum of C 10 -C 13 -LABs) in runoff samples collected from the eight major riverine outlets of the Pearl River Delta (PRD) of China ranged from 1.4 to 6124 ng/L in the dissolved phase and from 0.01 to 11.4 μg/g dry weight in the particulate phase during March 2005-February 2006. The annual riverine flux of ΣLABs from the PRD to the coastal ocean was estimated at approximately 14 tons/yr. The inventories of ΣLABs in agricultural lands of Guangdong Province ranged from 313 to 1825 kg/yr. The early and late rice fields were the major sink of LABs, accounting for approximately 68% of total LABs inventory in agricultural lands. The social-economically estimated annual discharge of LABs from household detergents in the PRD was ∼696 tons/yr, more than an order of magnitude higher than that estimated from field measurements (about 14 tons/yr), which was attributed to several factors. - Occurrence of LABs in riverine runoff of the Pearl River Delta (China) was examined

Design of digital trapezoidal shaping filter based on LabVIEW

International Nuclear Information System (INIS)

Liu Yujuan; Qin Guoxiu; Yang Zhihui; Zhang Xiaodong

2013-01-01

It describes the design of a digital trapezoidal shaping filter to nuclear signals based on LabVIEW. A method of optimizing the trapezoidal shaping filter's parameters was presented and tested, and the test results of the effect of shaping filter algorithm were studied. (authors)

Objectives of research activities in Biology Branch, Chalk River Nuclear Laboratories, 1976

International Nuclear Information System (INIS)

1977-03-01

The primary responsibility assigned to the Biology Branch within the framework of CRNL has been an active engagement in basic research related to the assessment of radiation hazards, particularly those to be expected after exposure to relatively low doses of radiation delivered at low dose-rates. The present group is characterized by a broad interest in the entire chain of events by which the initial radiation-induced changes in the living cell are translated into biological effects, with a special focus of attention on the mechanisms by which the initial damage can be largely repaired and by which the risks to man are modified under different circumstances. The basic concepts in radiation biology and risk estimates are reviewed in the light of recent literature on these topics. The current and proposed research activities of the Biology Branch are described. General and specific recommendations for future activities are given. (author)

Probabilistic evaluation of risks associated with aviation, road, railway and river traffic adjacent to nuclear power plants in France

International Nuclear Information System (INIS)

Procaccia, H.; Gobert, T.

1978-01-01

Electricite de France has developed a methodology to calculate the potential impact of risks to a nuclear power plant subsequent to an accident occurring on transportation networks in the vicinity of a nuclear site. Risks entailed in aviation, and in road, rail, and river traffic have been estimated. This methodology has been applied to all sites planned in France

Follow-up of CRNL employees involved in the NRX reactor clean-up

International Nuclear Information System (INIS)

Werner, M.M.; Myers, D.K.; Morrison, D.P.

1982-07-01

Data available to date on the mortality of continuing and retired employees of the Chalk River Nuclear Laboratories are consistent with the Σhealthy workerΣ effect that has been observed in similar studies at other nuclear facilities. Because of an accident at the NRX research reactor in December 1952, the reactor was largely dismantled and rebuilt in 1953-54. These operations involved appreciable radiation exposures to a number of employees. The follow-up of the 850 on-site AECL staff involved in the clean-up has indicated that there were no unusual patterns in the mortality of this group when compared with those of the general population of Ontario

The Canadian development program for conditioning CANDU reactor wastes for disposal

International Nuclear Information System (INIS)

Charlesworth, D.H.; Bourns, W.T.; Buckley, L.P.

1978-07-01

Currently, radioactive wastes arising from the operation of Canadian nuclear reactors are placed in interim storage in concrete containment structures except for gaseous and liquid wastes containing small amounts of radioactivity which are dispersed. With the objective of replacing storage by permanent disposal, a program is underway to develop and demonstrate an integrated process for converting all reactor wastes to a stable, leach-resistant form which will immobilize the radionuclides in the waste repository. The major tool for this development is a Waste Treatment Centre, now being constructed at Chalk River Nuclear Laboratories, which will combine reverse-osmosis, incineration, evaporation and bituminizing processes. (author)

Savannah River Site, spent nuclear fuel management, draft environmental impact statement

International Nuclear Information System (INIS)

1998-12-01

The management of spent nuclear fuel (SNF) has been an integral part of the mission of the Savannah River Site (SRS) for more than 40 years. Until the early 1990s, SNF management consisted primarily of short-term onsite storage and reprocessing in the SRS chemical separation facilities to produce strategic nuclear materials. With the end of the Cold War, the US Department of Energy (DOE) decided to phase out reprocessing of SNF for the production of nuclear weapons materials. Therefore, the management strategy for this fuel has shifted from short-term storage and reprocessing for the recovery of highly-enriched uranium and transuranic isotopes to stabilization, when necessary, and interim storage pending final disposition that includes preparing aluminum-based SNF for placement in a geologic repository. In addition to the fuel already onsite, the SRS will receive SNF from foreign research reactors until 2009 and from domestic research reactors until, potentially, 2035. As a result, the safe and efficient management of SNF will continue to be an important SRS mission. This EIS evaluates the potential environmental impacts of DOE's proposed plans for management SNF assigned to SRS

Life-history strategies as a tool to identify conservation constraints: A case-study on ants in chalk grasslands

NARCIS (Netherlands)

Noordwijk, C.G.E.; Boer, P.; Mabelis, A.A.; Verberk, W.C.E.P.; Siepel, H.

2012-01-01

Species’ life-history traits underlie species–environment relationships. Therefore, analysis of species traits, combined into life-history strategies, can be used to identify key factors shaping the local species composition. This is demonstrated in a case-study on ants in chalk grasslands. We

Vision Lab

Data.gov (United States)

Federal Laboratory Consortium — The Vision Lab personnel perform research, development, testing and evaluation of eye protection and vision performance. The lab maintains and continues to develop...

Evaluation of nuclear facility decommissioning projects. Project summary report, Elk River Reactor

International Nuclear Information System (INIS)

Miller, R.L.; Adams, J.A.

1982-12-01

This report summarizes information concerning the decommissioning of the Elk River Reactor. Decommissioning data from available documents were input into a computerized data-handling system in a manner that permits specific information to be readily retrieved. The information is in a form that assists the Nuclear Regulatory Commission in its assessment of decommissioning alternatives and ALARA methods for future decommissionings projects. Samples of computer reports are included in the report. Decommissioning of other reactors, including NRC reference decommissioning studies, will be described in similar reports

Long term reliability analysis of standby diesel generators

International Nuclear Information System (INIS)

Winfield, D.J.

1988-01-01

The long term reliability of 11 diesel generators of 125 to 250 kV A size has been analysed from 26 years of data base information on individual diesel service as standby power supplies for the Chalk River research reactor facilities. Failure to start on demand and failure to run data is presented and failure by diesel subsystem and multiple failures are also analysed. A brief comparison is made with reliability studies of larger diesel generator units used for standby power service in nuclear power plants. (author)

Durability aspects of high-performance concretes for a waste repository. Appendix 3: Canada

International Nuclear Information System (INIS)

Philipose, K.E.

2001-01-01

The IRUS facility for the disposal of low level radioactive waste at the Chalk River Nuclear Laboratories in Ontario, Canada relies on the durability of concrete for the required 500 years of service life. A research programme based on laboratory testing to design a durable concrete and assess its long-term behaviour was initiated in 1988. This appendix discusses the methodology to assess the long-term behaviour of concrete, and some initial observations. Longevity predictions for concrete formulations based on diffusion testing are also presented

Opening address

International Nuclear Information System (INIS)

Levesque, R.J.A.

1990-01-01

The Canadian Atomic Energy Control Board (AECB) has funded, and continues to fund, research into genetic effects of radiation. Of particular note is the continuation of studies into the apparent excess of leukemia in children in the area around the Bruce Nuclear Power Development, and the apparent deficit of leukemia in children around the Chalk River Laboratories, neither of which appears to be statistically significant. The sponsorship of meetings such as this is another way in which the AECB supports research into radiation effects. (L.L.)

The measurement of natural uranium in urine by fluorometry

International Nuclear Information System (INIS)

Kramer, G.H.; Johnson, J.R.; Green, W.

1984-02-01

The fluorometric method of measuring natural uranium in urine that is currently used by the Bioassay Laboratory at Chalk River Nuclear Laboratories has been tested, optimized and documented. The method, which measures the fluorescence of uranium in a fused sodium fluoride pellet, has been shown to be quench independent and is routinely used to measure uranium concentrations in the range of 1 μg/L to 90 μg/L. The fluorimeter has a dynamic range of 0.2 μg/L to 200 μg/L

Uranium-phosphate relationship in phosphated chalks of the Mons and Picardie Bassins

Energy Technology Data Exchange (ETDEWEB)

Quinif, Y; Charlet, J M; Dupuis, C; Robaszynski, F [Faculte Polytechnique de Mons (Belgium)

1981-11-30

The lithological and geochemical conditions relative to the ''Senonian'' phosphatic chalks are relatively simple in the Basins of Mons (Belgium) and of Picardy (France). Their characteristics permit us to study chiefly the uranium-phosphate relation. It appears a very good linear correlation between the phosphate and the uranium. The coefficient U/P/sub 2/O/sub 5/ remains a constant from the bottom to the top of the same section, but changes in space for synchronic formations (lateral variation of geochemical facies) and in time for two separated basins.

Mechanisms for surface contamination of soils and bottom sediments in the Shagan River zone within former Semipalatinsk Nuclear Test Site.

Science.gov (United States)

Aidarkhanov, A O; Lukashenko, S N; Lyakhova, O N; Subbotin, S B; Yakovenko, Yu Yu; Genova, S V; Aidarkhanova, A K

2013-10-01

The Shagan River is the only surface watercourse within the former Semipalatinsk Test Site (STS). Research in the valley of the Shagan River was carried out to study the possible migration of artificial radionuclides with surface waters over considerable distances, with the possibility these radionuclides may have entered the Irtysh River. The investigations revealed that radioactive contamination of soil was primarily caused by the first underground nuclear test with soil outburst conducted at the "Balapan" site in Borehole 1004. The surface nuclear tests carried out at the "Experimental Field" site and global fallout made insignificant contributions to contamination. The most polluted is the area in the immediate vicinity of the "Atomic" Lake crater. Contamination at the site is spatial. The total area of contamination is limited to 10-12 km from the crater piles. The ratio of plutonium isotopes was useful to determine the source of soil contamination. There was virtual absence of artificial radionuclide migration with surface waters, and possible cross-border transfer of radionuclides with the waters of Shagan and Irtysh rivers was not confirmed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Sister Lab Program Prospective Partner Nuclear Profile: Malaysia

International Nuclear Information System (INIS)

Bissani, M; Tyson, S

2006-01-01

The Malaysian Deputy Prime Minister Tun Dr Ismail Abdul Rahman suggested in the early 1970s that Malaysia should have a role in the development of nuclear science and technology for peaceful purposes. Accordingly, the Center for the Application of Nuclear Energy (CRANE) was established, with a focus on the development of a scientific and technical pool critical to a national nuclear power program. The Malaysian Cabinet next established the Tun Ismail Atomic Research Center (TIARC) under the Ministry of Science, Technology and the Environment on 19 September 1972, at a site in Bangi, about 35 km south of Kuala Lampur. On 28 June 1982, the PUSPATI reactor, a 1-MW TRIGA MK-II research reactor, first reached criticality. On 10 August 1994, TIARC was officially renamed as the Malaysian Institute for Nuclear Technology Research (MINT). In addition to radioisotope production and neutron radiography conducted at the PUSPATI research reactor, MINT also supports numerous programs employing nuclear technology for medicine, agriculture and industry, and has been involved in both bilateral and multilateral technical cooperation to extend its capabilities. As an energy exporting country, Malaysia has felt little incentive to develop a nuclear energy program, and high level opposition within the government discouraged it further. A recent statement by Malaysia's Science, Technology and Innovation Minister supported this view, indicating that only a near-catastrophic jump in world oil prices might change the government's view. However, the rate at which Malaysia is using its natural gas and oil reserves is expected to force it to reassess the role of nuclear energy in the near future. In addition, the government does intend to construct a radioactive waste repository to dispose of naturally occurring radioactive materials (extracted during tin mining, in particular). Also, Malaysia's growing economy could encourage expansion in Malaysia's existing nuclear-applications programs

Designing inquiry learning spaces for online labs in the Go-Lab platform

NARCIS (Netherlands)

de Jong, Ton; Gillet, Dennis; Sotiriou, Sofoklis; Agogi, Ellinogermaniki; Zacharia, Zacharias

2015-01-01

The Go-Lab project (http://www.go-lab-project.eu/) aims to enable the integration of online labs through inquiry-based learning approaches into science classrooms. Through the use of an advanced plug and play technological solution the Go-Lab project opens up remote science laboratories, data

Tilting oil-water contact in the chalk of Tyra Field as interpreted from capillary pressure data

DEFF Research Database (Denmark)

Fabricius, Ida Lykke; Rana, M.A.

2010-01-01

The Tyra Field in the central North Sea is located in Palaeogene and Upper Cretaceous chalk. It contains a natural gas zone underlain by an oil leg. Based on analysis of logs and core data from ten wells drilled prior to the field being put into production, normalized water saturation depth-trend...... inequilibriumin the aquifer following tectonic tilting....

The Use of Hydrograph Analysis and Impulse Response Functions to Improve Understanding of Groundwater Flooding: A Case Study from the Chalk Aquifer, United Kingdom.

Science.gov (United States)

Ascott, M.; Bloomfield, J.; Macdonald, D.; Marchant, B.; McKenzie, A.

2017-12-01

The Cretaceous Chalk, the most important aquifer in the United Kingdom (UK) for public water supply, underlies many large cities in southern and eastern England including parts of London, however, it is prone to groundwater flooding. We have developed a new approach to analyse the spatio-temporal extent of groundwater flooding using statistical analysis of groundwater level hydrographs and impulse response functions (IRFs) applied to a major Chalk groundwater flooding event in the UK during winter 2013/14. Using monthly groundwater levels for 26 boreholes in the Chalk and a new standardised index for groundwater flooding, we have: estimated standardised series; grouped them using k-means cluster analysis; and, cross-correlated the cluster centroids with the Standardised Precipitation Index accumulated over time intervals between 1 and 60 months. This analysis reveals two spatially coherent groups of standardised hydrographs which respond to precipitation over different timescales. We estimate IRF models of the groundwater level response to effective precipitation for three boreholes in each group. The IRF models support the SPI analysis showing different response functions between the two groups. If we apply identical effective precipitation inputs to each of the IRF models we see differences between the hydrographs from each group. It is proposed that these differences are due to the intrinsic, hydrogeological properties of the Chalk and of overlying relatively low permeability superficial deposits. Consequently, it is concluded that the overarching controls on groundwater flood response are a complex combination of antecedent conditions, rainfall and catchment hydrogeological properties. These controls should be taken into consideration when anticipating and managing future groundwater flood events.

Draft environmental impact statement. River Bend Nuclear Power Station, Unit 1

International Nuclear Information System (INIS)

Anon.

1980-01-01

Federal financing of an undivided ownership interest of River Bend Nuclear Power Station Unit 1 on a 3293-acre site near St. Francisville, Louisiana is proposed in a supplement to the final environmental impact statement of September 1974. The facility would consist of a boiling-water reactor that would produce a maximum of 2894 megawatts (MW) of electrical power. A design level of 3015 MW of electric power could be realized at some time in the future. Exhaust steam would be cooled by mechanical cooling towers using makeup water obtained from and discharged to the Mississippi River. Power generated by the unit would be transmitted via three lines totaling 140 circuit miles traversing portions of the parishes of West Feliciana, East Feliciana, East Baton Rouge, West Baton Rouge, Pointe Coupee, and Iberville. The unit would help the applicant meet the power needs of rural electric consumers in the region, and the applicant would contribute significanlty to area tax base and employment rolls during the life of the unit. Construction related activities would disturb 700 forested acres on the site and 1156 acres along the transmission routes. Of the 60 cubic feet per second (cfs) taken from the river, 48 cfs would evaporate during the cooling process and 12 cfs would return to the river with dissolved solids concentrations increased by 500%. The terrace aquifer would be dewatered for 16 months in order to lower the water table at the building site, and Grants Bayou would be transformed from a lentic to a lotic habitat during this period. Fogging and icing due to evaporation and drift from the cooling towers would increase slightly. During the construction period, farming, hunting, and fishing on the site would be suspended, and the social infractructure would be stressed due to the influx of a maximum of 2200 workers

Nuclear technology and beekeeping industry: much more than atoms and bees; Tecnologia nuclear y apicultura: mucho mas que atomos y abejas

Energy Technology Data Exchange (ETDEWEB)

Rapisarda, Vicenzo M; Hussein, Ana M [Comision Nacional de Energia Atomica, Ezeiza (Argentina). Dept. de Aplicaciones Tecnologicas y Agropecuarias

2002-06-01

Argentine beekeeping industry is the first honey world exporter and the third honey world producer. At the present work, the authors try to show why nuclear technology is one of the best tools for beekeepers to reach health and quality standards required by national and international organisations. Irradiation from Cobalt 60 aim to fight against American foul brood, European foul brood and Chalk brood, besides it is such a good mechanism to degradate acaricides residuals in wax which were used in order to kill Varroa jacobsoni Oud. During the last 30 years, studies have demonstrated honey bees are wonderful sentinel species which represent an incomparable help to nuclear activity through environmental monitoring. Nuclear energy, health care, commercial affairs and environment meet together at Ezeiza Atomic Center, where many developments have been done and new projects are carried out. (author)

The Turnover Process at Chalk River Laboratories from Operations to Decommissioning

International Nuclear Information System (INIS)

Pottelberg, Paul; Tremblay, Roger

2016-01-01

Canadian Nuclear Laboratories (CNL) has 200 facilities that account for approximately 2 million square feet of building space. Currently there are 23 facilities undergoing various stages of Decommissioning. An additional 30 facilities are scheduled to be turned over to Decommissioning in 2016. CNL is currently restructuring to transition to a Government Owned/Contractor Operated (GoCo) organization and there will be a focus to accelerate the Decommissioning of legacy facilities on site. In the past, facilities were shutdown and left in various configurations with limited documentation or limited staff knowledge of the status of the facility at the start of Decommissioning. Recently, guidelines have been developed to ensure that any facility being turned over is put into a proper and documented safe shutdown configuration. This paper will look at CNL's process for turnover of facilities from Operations to Decommissioning and identify some of the key Lessons Learned. The turnover of nuclear facilities, administrative and support buildings, components or areas from Operations to Decommissioning needs to be documented and managed to ensure Health, Safety, Security and Environmental (HSSE) risks are identified, eliminated or effectively controlled. At CNL, the turnover document Table of Contents is: Introduction and Purpose; Facility Boundaries; Known Deficiencies; Facility Status; Shutdown Status; Hazards; System/Equipment; Drawings/Maps/Records; Significant Environmental Aspects (SEAs); Interface; and other Transfer Documentation. The transfer documentation specifically covers: - Defined boundaries of the facility, building, component or area at the time of turnover; - Identification of all deficiencies associated with the facility, building, component or area and the person, after turnover, who will be responsible for correcting them; - Confirmation of the status of the facility, building, component or area at the time of turnover with respect to: - The status

Chernobyl nuclear accident hydrologic analysis and emergency evaluation of radionuclide distributions in the Dnieper River, Ukraine, during the 1993 summer flood

International Nuclear Information System (INIS)

Voitsekhovitch, O.V.; Zheleznyak, M.J.

1994-06-01

This report describes joint activities of Program 7.1.F, ''Radionuclide Transport in Water and Soil Systems,'' of the USA/Commonwealth of Independent States (CIS) Joint Coordinating Committee of Civilian Nuclear Reactor Safety to study the hydrogeochemical behavior of radionuclides released to the Pripyat and Dnieper rivers from the Chernobyl Nuclear Power Plant in Ukraine. These joint activities included rapid evaluation of radionuclide distributions in the Pripyat and Dnieper river system and field data evaluation and modeling for the 1993 summer flood to assist the Ukrainian government in their emergency response during the flood. In July-August 1993, heavy rainfall over the Pripyat River Catchment in Belarus and Ukraine caused severe flooding, significantly raising 90 Sr concentrations in the river. Near the Chernobyl area, the maximum 90 Sr concentration in the Pripyat River reached 20--25 PCi/L in early August; near the Pripyat River mouth, the concentration rose to 35 pCi/L. The peak 90 Sr concentration in the Kiev Reservoir (a major source of drinking water for Kiev) was 12 pCi/L. Based on these measured radionuclide levels, additional modeling results and the assumption of water purification in a water treatment station, 90 Sr concentrations in Kiev's drinking water were estimated to be less than 8 pCi/L. Unlike 90 Sr, 137 Cs concentrations in the Pripyat River during the flood did not rise significantly to the pre-flood levels. Estimated 137 Cs concentrations for the Kiev drinking water were two orders of magnitude lower than the drinking water standard of 500 pCi/L for 137 Cs

Overview of the spent nuclear fuel storage facilities at the Savannah River Site

International Nuclear Information System (INIS)

Conatser, E.R.; Thomas, J.E.

2000-01-01

The May 1996 Record of Decision on a Proposed Nuclear Weapons Nonproliferation Policy concerning Foreign Research Reactor Spent Nuclear Fuel initiated a 13 year campaign renewing a policy to support the return of spent nuclear fuel containing uranium of U.S. origin from foreign research reactors to the United States. As of December 1999, over 22% of the approximately 13,000 spent nuclear fuel assemblies from participating countries have been returned to the Savannah River Site (SRS). These ∼2650 assemblies are currently stored in two dedicated SRS wet storage facilities. One is the Receiving Basin for Off-site Fuels (RBOF) and the other as L-Basin. RBOF, built in the early 60's to support the 'Atoms for Peace' program, has been receiving off-site fuel for over 35 years. RBOF has received approximately 1950 casks since startup and has the capability of handling all of the casks currently used in the FRR program. However, RBOF is 90% filled to capacity and is not capable of storing all of the fuel to be received in the program. L-Basin was originally used as temporary storage for materials irradiated in SRS's L-Reactor. New storage racks and other modifications were completed in 1996 that improved water quality and allowed the L-Basin to receive, handle and store spent nuclear fuel assemblies and components from off-site. The first foreign cask was received into the L-Area in April 1997 and approximately 105 foreign and domestic casks have been received since that time. This paper provides an overview of activities related to fuel receipt and storage in both the Receiving Basin for Off-site Fuels (RBOF) and L-Basin facilities. It will illustrate each step of the fuel receipt program from arrival of casks at SRS through cask unloading and decontamination. It will follow the fuel handling process, from fuel unloading, through the cropping and bundling stages, and final placement in the wet storage rack. Decontamination methods and equipment will be explained to show

Overview of the spent nuclear fuel storage facilities at the Savannah River Site

International Nuclear Information System (INIS)

Thomas, Jay

1999-01-01

The May 1996 Record of Decision on a Proposed Nuclear Weapons Nonproliferation Policy concerning Foreign Research Reactor Spent Nuclear Fuel initiated a 13 year campaign renewing a policy to support the return of spent nuclear fuel containing uranium of U.S.-origin from foreign research reactors to the United States. As of July 1999, over 18% of the approximately 13,000 spent nuclear fuel assemblies from participating countries have been returned to the Savannah River Site (SRS). These 2400 assemblies are currently stored in two dedicated SRS wet storage facilities. One is the Receiving Basin for Off-site Fuels (RBOF) and the other as L-Basin. RBOF, built in the early 60's to support the 'Atoms for Peace' program, has been receiving off-site fuel for over 35 years. RBOF has received approximately 1950 casks since startup and has the capability of handling all of the casks currently used in the FRR program. However, RBOF is 90% filled to capacity and is not capable of storing all of the fuel to be received in the program. L-Basin was originally used as temporary storage for materials irradiated in SRS's L-Reactor. New storage racks and other modifications were completed in 1996 that improved water quality and allowed L-Basin to receive, handle and store spent nuclear fuel assemblies and components from off-site. The first foreign cask was received into L-Area in April 1997 and approximately 86 foreign and domestic casks have been received since that time. This paper provides an overview of activities related to fuel receipt and storage in both the Receiving Basin for Off-site Fuels (RBOF) and L-Basin facilities. It will illustrate each step of the fuel receipt program from arrival of casks at SRS through cask unloading and decontamination. It will follow the fuel handling process, from fuel unloading, through the cropping and bundling stages, and final placement in the wet storage rack. Decontamination methods and equipment will be explained to show how the empty

Overview of the spent nuclear fuel storage facilities at the Savannah River Site

Energy Technology Data Exchange (ETDEWEB)

Conatser, E.R.; Thomas, J.E. [Westinghouse Savannah River Company, Aiken, SC 29808 (United States)

2000-07-01

The May 1996 Record of Decision on a Proposed Nuclear Weapons Nonproliferation Policy concerning Foreign Research Reactor Spent Nuclear Fuel initiated a 13 year campaign renewing a policy to support the return of spent nuclear fuel containing uranium of U.S. origin from foreign research reactors to the United States. As of December 1999, over 22% of the approximately 13,000 spent nuclear fuel assemblies from participating countries have been returned to the Savannah River Site (SRS). These {approx}2650 assemblies are currently stored in two dedicated SRS wet storage facilities. One is the Receiving Basin for Off-site Fuels (RBOF) and the other as L-Basin. RBOF, built in the early 60's to support the 'Atoms for Peace' program, has been receiving off-site fuel for over 35 years. RBOF has received approximately 1950 casks since startup and has the capability of handling all of the casks currently used in the FRR program. However, RBOF is 90% filled to capacity and is not capable of storing all of the fuel to be received in the program. L-Basin was originally used as temporary storage for materials irradiated in SRS's L-Reactor. New storage racks and other modifications were completed in 1996 that improved water quality and allowed the L-Basin to receive, handle and store spent nuclear fuel assemblies and components from off-site. The first foreign cask was received into the L-Area in April 1997 and approximately 105 foreign and domestic casks have been received since that time. This paper provides an overview of activities related to fuel receipt and storage in both the Receiving Basin for Off-site Fuels (RBOF) and L-Basin facilities. It will illustrate each step of the fuel receipt program from arrival of casks at SRS through cask unloading and decontamination. It will follow the fuel handling process, from fuel unloading, through the cropping and bundling stages, and final placement in the wet storage rack. Decontamination methods and equipment

Isolation and identification of indigenous lactic acid bacteria from North Sumatra river buffalo milk

OpenAIRE

Heni Rizqiati; Cece Sumantr; Ronny Rachman Noor; E. Damayanthi; E. I. Rianti

2015-01-01

Buffalo milk is a source of various lactic acid bacteria (LAB) which is potential as culture starter as well as the probiotic. This study was conducted to isolate and identify LAB from indigenous North Sumatra river buffalo milk. Lactic acid bacteria was isolated and grown in medium De Man Rogosa Sharpe Agar (MRSA). The isolation was conducted to obtain pure isolate. The identification of LAB was studied in terms of morphology, physiology, biochemistry and survival on low pH. Morphology test...

Decontamination flowsheet development for a waste oil containing mixed radioactive contaminants

International Nuclear Information System (INIS)

Vijayan, S.; Buckley, L.P.

1993-01-01

The majority of waste oils contaminated with both radioactive and hazardous components are generated in nuclear power plant, research lab. and uranium-refinery operations. The waste oils are complex, requiring a detailed examination of the waste management strategies and technology options. It may appear that incineration offers a total solution, but this may not be true in all cases. An alternative approach is to decontaminate the waste oils to very low contaminant levels, so that the treated oils can be reused, burned as fuel in boilers, or disposed of by commercial incineration. This paper presents selected experimental data and evaluation results gathered during the development of a decontamination flowsheet for a specific waste oil stores at Chalk River Labs. (CRL). The waste oil contains varying amounts of lube oils, grease, paint, water, particulates, sludge, light chloro- and fluoro-solvents, polychlorinated biphenyls (PCB), complexing chemicals, uranium, chromium, iron, arsenic and manganese. To achieve safe management of this radioactive and hazardous waste, several treatment and disposal methods were screened. Key experiments were performed at the laboratory-scale to confirm and select the most appropriate waste-management scheme based on technical, environmental and economic criteria. The waste-oil-decontamination flowsheet uses a combination of unit operations, including prefiltration, acid scrubbing, and aqueous-leachage treatment by precipitation, microfiltration, filter pressing and carbon adsorption. The decontaminated oil containing open-quotes de minimisclose quotes levels of contaminants will undergo chemical destruction of PCBs and final disposal by incineration. The recovered uranium will be recycled to a uranium milling process

Innovations in STEM education: the Go-Lab federation of online labs

NARCIS (Netherlands)

de Jong, Anthonius J.M.; Sotiriou, Sofoklis; Gillet, Dennis

2014-01-01

The Go-Lab federation of online labs opens up virtual laboratories (simulation), remote laboratories (real equipment accessible at distance) and data sets from physical laboratory experiments (together called “online labs”) for large-scale use in education. In this way, Go-Lab enables inquiry-based

Human Resources Development for Rooppur Nuclear Power Programme in Bangladesh

International Nuclear Information System (INIS)

Hossain, Md. Kabir

2014-01-01

Conclusions: • Bangladesh faces a huge challenge in implementing the Rooppur NPP and its total nuclear power; • A preliminary assessment has been chalked out a plan to find out methods that can be applied to find out our gaps and then fill them up; • Bangladesh seeks cooperation from the Russian Federation in the form assistance package like National training courses, Seminar/Workshop, Expert Mission/Review and other form of bilateral arrangements in establishing infrastructure for “Rooppur NPP” building;

Jefferson Lab, a status report

International Nuclear Information System (INIS)

Dunham, B.M.

1996-01-01

Thomas Jefferson National Accelerator Facility (Jefferson Lab; formerly known as CEBAF), operates a 4 GeV, 200 microA continuous wave (CW) electron accelerator that re-circulates the beam five times through two superconducting 400 MeV linacs. Electrons can be extracted from any of the five recirculation passes and beam can be simultaneously delivered to the three experimental halls. As the commissioning stage nears completion, the accelerator is becoming a fully operational machine. Experiments in Hall C have been underway since November 1995 with beam powers of over 300 kW at various energies. Hall A has received beam for spectrometer commissioning, while Hall B is expected to receive its first beam in the fall of 1996. Accelerator availability of greater than 70% during physics runs and excellent beam quality have contributed to making Jefferson Lab a world class laboratory for accelerator-based electromagnetic nuclear physics. With the high performance of the superconducting RF cavities, machine upgrades to 6 GeV, and eventually 8 to 10 GeV are now in the planning stages. Operational and commissioning details concerning all aspects of the machine will be discussed

Jefferson Lab, a status report

International Nuclear Information System (INIS)

Dunham, B.M.

1996-01-01

Thomas Jefferson National Accelerator Facility (Jefferson Lab; formerly known as CEBAF), operates a 4 GeV, 200 μA continuous wave (CW) electron accelerator that re-circulates the beam five times through two superconducting 400 MeV linacs. Electrons can be extracted from any of the five recirculation passes and beam can be simultaneously delivered to the three experimental halls. As the commissioning stage nears completion, the accelerator is becoming a fully operational machine. Experiments in Hall C have been underway since November 1995 with beam powers of over 300 kW at various energies. Hall A has received beam for spectrometer commissioning, while Hall B is expected to receive its first beam in the fall of 1996. Accelerator availability of greater than 70% during physics runs and excellent beam quality have contributed to making Jefferson Lab a world class laboratory for accelerator-based electromagnetic nuclear physics. With the high performance of the superconducting RF cavities, machine upgrades to 6 GeV, and eventually 8 to 10 GeV are now in the planning stages. Operational and commissioning details concerning all aspects of the machine will be discussed. (author)

Full-length fuel rod behavior under severe accident conditions

International Nuclear Information System (INIS)

Lombardo, N.J.; Lanning, D.D.; Panisko, F.E.

1992-12-01

This document presents an assessment of the severe accident phenomena observed from four Full-Length High-Temperature (FLHT) tests that were performed by the Pacific Northwest Laboratory (PNL) in the National Research Universal (NRU) reactor at Chalk River, Ontario, Canada. These tests were conducted for the US Nuclear Regulatory Commission (NRC) as part of the Severe Accident Research Program. The objectives of the test were to simulate conditions and provide information on the behavior of full-length fuel rods during hypothetical, small-break, loss-of-coolant severe accidents, in commercial light water reactors

Report of activities no. l9, 1984

International Nuclear Information System (INIS)

1984-01-01

The accelerators at the Laboratoire de physique nucleaire are no longer used for fundamental nuclear research, but have found a new role in studies of solid state physics, microelectronics, biochemistry, and applied physics. Accelerators at TRIUMF, CERN, Chalk River and other locations are being used for more fundamental studies in lepton production, instrumentation, and particle physics. Another major project is the development of a data acquisitions system for an 8-pi spectrometer. The theoretical physics group is working in the areas of nucleon-nucleon diffusion in the quark model, gauge theory, and the skyrmion model

Design, development and safety assessment of the IRUS repository for disposal of low-level radioactive waste

International Nuclear Information System (INIS)

Hardy, D.G.; Philipose, K.E.; Jarvis, R.G.

1988-01-01

This paper reports on a program underway at the Chalk River Nuclear Laboratories (CRNL) to proceed from the current practice of storage of low-level radioactive wastes (LLRW) to permanent disposal. The strategy involved is to sort the LLRW into broad categories based on the duration of their hazard and to match each category to an appropriate disposal technology. Initially, work is concentrating on the development of a belowground vault, labeled as the intrusion-resistant underground structure (IRUS), suitable for wastes with a hazardous lifetime of 500 years or less

Conceptual design of a two-phase flow absorber system for neutron flux regulation in a CANDU-PHW-1250 reactor

International Nuclear Information System (INIS)

Lepp, R.M.; Moeck, E.O.

1979-07-01

A two-phase absorber control (TOPAC) system has been under development at the Chalk River Nuclear Laboratories to meet the need for improved spatial neutron flux control for future CANDU power reactors. Aspects of the conceptual design study presented in this paper include system controllability, in-reactor noise sensitiity, the effect of equipment malfunctions on plant operation, and a comparison with competing systems. The TOPAC system is shown to be a viable alternative to existing and future neutron flux regulating systems based on liquid H 2 O zone compartments. (auth)

Internal radioactive contamination in selected groups of CRNL employees

International Nuclear Information System (INIS)

Evans, D.W.S.

1975-10-01

This report details the development and execution of a 30 month program designed to characterize the magnitude and distribution of internal radioactive contaminaton amongst selected groups of employees at Chalk River Nuclear Laboratories, using a shadow shield whole-body counter. The results show that the levels of contamination in these employees are very low, and no contaminant was present in amounts exceeding 10% of the maximum permissible body burden, with the exception of a medically administered radionuclide (selenium-75). Details of the time course of some of the body burdens are also furnished. (author)

Movement of radionuclides from river to ground water in vicinity of location for nuclear power plant

International Nuclear Information System (INIS)

Knezevic, Lj.; Lazic, S.; Vukovic, Z.

1984-01-01

The possibility of ground water contamination caused by radionuclide from river water to which liquid effluents were released from a nuclear power station was estimated using one-dimensional transport model. This model is suitable for a homogeneous medium and takes into account hydraulic convection and dispersion as well as physical-chemical retardation for the various radionuclides. (author)

Towards an improved lithostratigraphic subdivision of the chalk group in the Netherlands North Sea area - A seismic stratigraphic approach

NARCIS (Netherlands)

Molen, A.S. van der; Wong, Th.E.

2007-01-01

In the Netherlands North Sea area, the Chalk Group has thus far been subdivided into the Cenomanian Texel Formation, the Turonian to Maastrichtian Ommelanden Formation and the Danian Ekofisk Formation. This paper describes the attempt to arrive at a more detailed lithostratigraphic subdivision for

Application of nuclear techniques to the measurement of rock density and transport of solid particles suspended in rivers

International Nuclear Information System (INIS)

Seddiki, A.

1984-10-01

In order to better understand hydron phenomens in semi-arid regions characterized by torrential rains, we measured solid particles suspended to dums and in rivers. We also determined the density profile of a drilling and density of saline solutions. We designed an automatic nuclear gauge used for measuring the concentration of particles suspended to rivers. The installation, calibration and operations of a LABEN gauge were done in BENI SLIMANE on the 27th and 28th of February, 1984. The first results we obtained were received on the 24th of April, 1984

Beyond Classroom, Lab, Studio and Field

Science.gov (United States)

Waller, J. L.; Brey, J. A.; DeMuynck, E.; Weglarz, T. C.

2017-12-01

When the arts work in tandem with the sciences, the insights of these disciplines can be easily shared and teaching and learning are enriched. Our shared experiences in classroom/lab/studio instruction and in art and science based exhibitions reward all involved. Our individual disciplines cover a wide range of content- Art, Biology, Geography, Geology- yet we connect on aspects that link to the others'. We easily move from lab to studio and back again as we teach—as do our students as they learn! Art and science education can take place outside labs and studios through study abroad, international workshops, museum or gallery spaces, and in forums like the National Academies' programs. We can reach our neighbors at local public gatherings, nature centers and libraries. Our reach is extended in printed publications and in conferences. We will describe some of our activities listed above, with special focus on exhibitions: "Layers: Places in Peril"; "small problems, BIG TROUBLE" and the in-progress "River Bookends: Headwaters, Delta and the Volume of Stories In Between". Through these, learning and edification take place between the show and gallery visitors and is extended via class visits and related assignments, field trips for child and adult learners, interviews, films and panel presentations. These exhibitions offer the important opportunities for exhibit- participating scientists to find common ground with each other about their varied work. We will highlight a recent collaborative show opening a new university-based environmental research center and the rewarding activities there with art and science students and professors. We will talk about the learning enhancement added through a project that brought together a physical geography and a painting class. We will explore how students shared the form and content of their research projects with each other and then, became the educators through paintings and text of their geoscience topics on gallery walls.

Polarized Source Performance and Developments at Jefferson Lab

International Nuclear Information System (INIS)

Matt Poelker; P. Adderley; J. Clark; A. Day; Joseph Grames; J. Hansknecht; P. Hartmann; R. Kazimi; P. Rutt; Charles Sinclair; M. Steigerwald

2000-01-01

The polarized photoinjector at Jefferson Lab continues to provide high average current, high polarization, high quality beam to nuclear physics Users in as many as three endstations simultaneously. Long lifetime operation has been obtained from two identical polarized guns. A new high power mode locked Ti-sapphire laser has been constructed to enhance the effective operating lifetime of the photoinjector. Efforts to enhance beam polarization and reduced helicity correlated beam systematic effects are underway

Progress report - Physical and Environmental Sciences - Physics Division, 1996 January 1 to December 31

International Nuclear Information System (INIS)

Powell, B.M.

1997-04-01

This document is the last Progress Report for the Neutron and Condensed Matter Science Branch, at Chalk River Labs of Atomic Energy of Canada Limited. The materials science program continued to include measurements of stress as a major component, but the determination of phase diagrams for specific alloys was also a prominent activity. Studies were made of two types of unusual magnetic materials. The magnetic properties of several oxide pyrochlore were investigated and spin waves were measured in the magnetic semiconductor, chalcopyrite. The crystal structures of the deuterated anti fluorite were determined and the reorientation of the ammonium ion was refined in detail. Differential scanning calorimetry measurements were used to investigate whether spontaneous phase separation into chiral domains occurs for mixtures of DPPC of opposite chirality. A new Neutron Velocity Selector was commissioned

Progress report - Physical and Environmental Sciences - Physics Division, 1996 January 1 to December 31

Energy Technology Data Exchange (ETDEWEB)

Powell, B.M. (ed.)

1997-04-01

This document is the last Progress Report for the Neutron and Condensed Matter Science Branch, at Chalk River Labs of Atomic Energy of Canada Limited. The materials science program continued to include measurements of stress as a major component, but the determination of phase diagrams for specific alloys was also a prominent activity. Studies were made of two types of unusual magnetic materials. The magnetic properties of several oxide pyrochlore were investigated and spin waves were measured in the magnetic semiconductor, chalcopyrite. The crystal structures of the deuterated anti fluorite were determined and the reorientation of the ammonium ion was refined in detail. Differential scanning calorimetry measurements were used to investigate whether spontaneous phase separation into chiral domains occurs for mixtures of DPPC of opposite chirality. A new Neutron Velocity Selector was commissioned.

Nuclear power plant analyzer

International Nuclear Information System (INIS)

Stritar, A.

1986-01-01

The development of Nuclear Power Plant Analyzers in USA is described. There are two different types of Analyzers under development in USA, the forst in Idaho and Los Alamos national Lab, the second in brookhaven National lab. That one is described in detail. The computer hardware and the mathematical models of the reactor vessel thermalhydraulics are described. (author)

Investigation of Lecturer's Chalk by x-ray Florescence and Fast Neutron Activation Techniques

International Nuclear Information System (INIS)

Hassan, M.F.

2011-01-01

Different samples of lecturer's chalk were studied, using X-ray florescence (XRF) and Fast Neutron Activation Analysis (FNAA) techniques to ensure the safety of its use. The K (X-rays) and the gamma-rays were measured, using Si(Li) and high-purity germanium (HPGe) spectrometers to detect and determine qualitatively and quantitatively the constituents of the studied samples. The concentrations of the elements (Ca and small traces of Al, Fe, Mg and Si) were measured and their presence was confirmed by gamma-ray, lifetime and/or XRF measurements.

PD Lab

NARCIS (Netherlands)

Bilow, Marcel; Entrop, Alexis Gerardus; Lichtenberg, Jos; Stoutjesdijk, Pieter

2015-01-01

PD Lab explores the applications of building sector related product development. PD lab investigates and tests digital production technologies like CNC milled wood connections. It will also act as a platform in its wider meaning to investigate the effects and influences of file to factory

The future supply of molybdenum-99

International Nuclear Information System (INIS)

Rojas-Burke, J.

1995-01-01

Since 1991, nuclear medicine physicians across the United States and much of the world have relied entirely on one 38-year-old nuclear reactor in Canada for the production of 99 Mo, the isotope used in 99m Tc generators. This situation came about quietly in the 1980s as alternate suppliers dropped out of the market, leaving Nordion International Inc. in Kanata, Ontario as the major supplier in the world. While Nordion has managed to maintain a steady supply of the essential material to radiopharmaceutical makers, a series of reactor failures and labor disputes have come close to halting production several times at the facilities that produce isotopes for Nordion in Chalk River, Ontario. 1 fig., 1 tab

FOREWORD: Jefferson Lab: A Long Decade of Physics

Science.gov (United States)

Montgomery, Hugh

2011-04-01

Jefferson Lab Jefferson Lab was created in 1984 and started operating in about 1996. 2011 is an appropriate time to try to take a look at the results that have appeared, what has been learned, and what has been exciting for our scientific community. Rather than attempt to construct a coherent view with a single author or at least a small number, we have, instead, invited small groups of people who have been intimately involved in the work itself to make contributions. These people are accelerator experts, experimentalists and theorists, staff and users. We have, in the main, sought reviews of the actual sub-fields. The primary exception is the first paper, which sets the scene as it was, in one person's view, at the beginning of Jefferson Lab. In reviewing the material as it appeared, I was impressed by the breadth of the material. Major advances are documented from form factors to structure functions, from spectroscopy to physics beyond the standard model of nuclear and particle physics. Recognition of the part played by spin, the helicities of the beams, the polarizations of the targets, and the polarizations of final state particles, is inescapable. Access to the weak interaction amplitudes through measurements of the parity violating asymmetries has led to quantification of the strange content of the nucleon and the neutron radius of lead, and to measurements of the electroweak mixing angle. Lattice QCD calculations flourished and are setting the platform for understanding of the spectroscopy of baryons and mesons. But the star of the game was the accelerator. Its performance enabled the physics and also the use of the technology to generate a powerful free electron laser. These important pieces of Jefferson Lab physics are given their place. As the third Director of Jefferson Lab, and on behalf of the other physicists and others presently associated with the lab, I would like to express my admiration and gratitude for the efforts of the directors, chief

Jefferson Lab: A Long Decade of Physics

International Nuclear Information System (INIS)

Montgomery, Hugh

2011-01-01

Jefferson Lab was created in 1984 and started operating in about 1996. 2011 is an appropriate time to try to take a look at the results that have appeared, what has been learned, and what has been exciting for our scientific community. Rather than attempt to construct a coherent view with a single author or at least a small number, we have, instead, invited small groups of people who have been intimately involved in the work itself to make contributions. These people are accelerator experts, experimentalists and theorists, staff and users. We have, in the main, sought reviews of the actual sub-fields. The primary exception is the first paper, which sets the scene as it was, in one person's view, at the beginning of Jefferson Lab. In reviewing the material as it appeared, I was impressed by the breadth of the material. Major advances are documented from form factors to structure functions, from spectroscopy to physics beyond the standard model of nuclear and particle physics. Recognition of the part played by spin, the helicities of the beams, the polarizations of the targets, and the polarizations of final state particles, is inescapable. Access to the weak interaction amplitudes through measurements of the parity violating asymmetries has led to quantification of the strange content of the nucleon and the neutron radius of lead, and to measurements of the electroweak mixing angle. Lattice QCD calculations flourished and are setting the platform for understanding of the spectroscopy of baryons and mesons. But the star of the game was the accelerator. Its performance enabled the physics and also the use of the technology to generate a powerful free electron laser. These important pieces of Jefferson Lab physics are given their place. As the third Director of Jefferson Lab, and on behalf of the other physicists and others presently associated with the lab, I would like to express my admiration and gratitude for the efforts of the directors, chief scientists

Towards an improved lithostratigraphic subdivision of the Chalk Group in the Netherlands North Sea area – A seismic stratigraphic approach

NARCIS (Netherlands)

Molen, A.S. van der; Wong, Th.E.

In the Netherlands North Sea area, the Chalk Group has thus far been subdivided into the Cenomanian Texel Formation, the Turonian to MaastrichtianOmmelanden Formation and the Danian Ekofisk Formation. This paper describes the attempt to arrive at a more detailed lithostratigraphicsubdivision for

Kinematic Labs with Mobile Devices

Science.gov (United States)

Kinser, Jason M.

2015-07-01

This book provides 13 labs spanning the common topics in the first semester of university-level physics. Each lab is designed to use only the student's smartphone, laptop and items easily found in big-box stores or a hobby shop. Each lab contains theory, set-up instructions and basic analysis techniques. All of these labs can be performed outside of the traditional university lab setting and initial costs averaging less than 8 per student, per lab.

Teachers' Perspectives on Online Virtual Labs vs. Hands-On Labs in High School Science

Science.gov (United States)

Bohr, Teresa M.

This study of online science teachers' opinions addressed the use of virtual labs in online courses. A growing number of schools use virtual labs that must meet mandated laboratory standards to ensure they provide learning experiences comparable to hands-on labs, which are an integral part of science curricula. The purpose of this qualitative case study was to examine teachers' perceptions of the quality and effectiveness of high school virtual labs. The theoretical foundation was constructivism, as labs provide student-centered activities for problem solving, inquiry, and exploration of phenomena. The research questions focused on experienced teachers' perceptions of the quality of virtual vs. hands-on labs. Data were collected through survey questions derived from the lab objectives of The Next Generation Science Standards . Eighteen teachers rated the degree of importance of each objective and also rated how they felt virtual labs met these objectives; these ratings were reported using descriptive statistics. Responses to open-ended questions were few and served to illustrate the numerical results. Many teachers stated that virtual labs are valuable supplements but could not completely replace hands-on experiences. Studies on the quality and effectiveness of high school virtual labs are limited despite widespread use. Comprehensive studies will ensure that online students have equal access to quality labs. School districts need to define lab requirements, and colleges need to specify the lab experience they require. This study has potential to inspire positive social change by assisting science educators, including those in the local school district, in evaluating and selecting courseware designed to promote higher order thinking skills, real-world problem solving, and development of strong inquiry skills, thereby improving science instruction for all high school students.

Thermal pollution of rivers and reservoirs by discharges of heated water from thermal and nuclear power plants

International Nuclear Information System (INIS)

Makarov, I.

1974-12-01

The problems are discussed of the thermal pollution of rivers and water reservoirs by discharges of heated water from thermal and nuclear power plants. The problems concerned are quantitative and qualitative changes in biocenoses, the disturbance or extinction of flora and fauna, physiological changes in organisms and changes in the hydrochemical regime. (Z.M.)

Assessment of the National Research Universal Reactor Proposed New Stack Sampling Probe Location for Compliance with ANSI/HPS N13.1-1999

Energy Technology Data Exchange (ETDEWEB)

Glissmeyer, John A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Antonio, Ernest J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Flaherty, Julia E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-02-29

This document reports on a series of tests conducted to assess the proposed air sampling location for the National Research Universal reactor (NRU) complex exhaust stack, located in Chalk River, Ontario, Canada, with respect to the applicable criteria regarding the placement of an air sampling probe. Due to the age of the equipment in the existing monitoring system, and the increasing difficulty in acquiring replacement parts to maintain this equipment, a more up-to-date system is planned to replace the current effluent monitoring system, and a new monitoring location has been proposed. The new sampling probe should be located within the exhaust stack according to the criteria established by the American National Standards Institute/Health Physics Society (ANSI/HPS) N13.1-1999, Sampling and Monitoring Releases of Airborne Radioactive Substances from the Stack and Ducts of Nuclear Facilities. These criteria address the capability of the sampling probe to extract a sample that represents the effluent stream. The internal Pacific Northwest National Laboratory (PNNL) project for this task was 65167, Atomic Energy Canada Ltd. Chalk River Effluent Duct Flow Qualification. The testing described in this document was guided by the Test Plan: Testing of the NRU Stack Air Sampling Position (TP-STMON-032).

Construction and engineering report for advanced nuclear fuel development facility

International Nuclear Information System (INIS)

Cho, S. W.; Park, J. S.; Kwon, S.J.; Lee, K. W.; Kim, I. J.; Yu, C. H.

2003-09-01

The design and construction of the fuel technology development facility was aimed to accommodate general nuclear fuel research and development for the HANARO fuel fabrication and advanced fuel researches. 1. Building size and room function 1) Building total area : approx. 3,618m 2 , basement 1st floor, ground 3th floor 2) Room function : basement floor(machine room, electrical room, radioactive waste tank room), 1st floor(research reactor fuel fabrication facility, pyroprocess lab., metal fuel lab., nondestructive lab., pellet processing lab., access control room, sintering lab., etc), 2nd floor(thermal properties measurement lab., pellet characterization lab., powder analysis lab., microstructure analysis lab., etc), 3rd floor(AHU and ACU Room) 2. Special facility equipment 1) Environmental pollution protection equipment : ACU(2sets), 2) Emergency operating system : diesel generator(1set), 3) Nuclear material handle, storage and transport system : overhead crane(3sets), monorail hoist(1set), jib crane(2sets), tank(1set) 4) Air conditioning unit facility : AHU(3sets), packaged air conditioning unit(5sets), 5) Automatic control system and fire protection system : central control equipment(1set), lon device(1set), fire hose cabinet(3sets), fire pump(3sets) etc

Status report on US-Russian laboratory-to-laboratory cooperation in nuclear materials protection, control and accounting

International Nuclear Information System (INIS)

Mullen, M.

1996-01-01

In April 1994, a new program of cooperation on nuclear materials protection, control, and accounting (MPC and A) was initiated between (1) the US Department of Energy and its laboratories and (2) nuclear institutes and enterprises of the Russian Federation. The program is called the Laboratory-to-Laboratory Nuclear Materials Protection, Control, and Accounting Program (Lab-to-Lab MPC and A Program); it is one of several, complementary US-Russian MPC and A programs. The purpose of the Lab-to-Lab MPC and A Program is to accelerate progress toward a goal that is vital to the national security interests of both countries: reducing the risk of nuclear weapons proliferation by strengthening MPC and A systems. In its first two years, the program has made significant progress and has expanded to include many additional Russian participants. It has also fostered a spirit of mutual understanding, partnership, and respect between US and Russian nuclear specialists, which has paved the way for advances in other MPC and A and nuclear security cooperative efforts. This paper reviews the current status of the program. In addition to summarizing the background and objectives of the program, the paper describes highlights of recent work and outlines future directions for Lab-to-Lab MPC and A cooperation

OpenLabNotes

DEFF Research Database (Denmark)

List, Markus; Franz, Michael; Tan, Qihua

2015-01-01

be advantageous if an ELN was Integrated with a laboratory information management system to allow for a comprehensive documentation of experimental work including the location of samples that were used in a particular experiment. Here, we present OpenLabNotes, which adds state-of-the-art ELN capabilities to Open......LabFramework, a powerful and flexible laboratory information management system. In contrast to comparable solutions, it allows to protect the intellectual property of its users by offering data protection with digital signatures. OpenLabNotes effectively Closes the gap between research documentation and sample management......, thus making Open-Lab Framework more attractive for laboratories that seek to increase productivity through electronic data management....

Electroosmotic dewatering of chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge

DEFF Research Database (Denmark)

Hansen, H.K.; Christensen, Iben Vernegren; Ottosen, Lisbeth M.

2003-01-01

. Casagrande's coefficients were determined for the four materials at different water contents. The experiments in this work showed that chalk could be dewatered from 40% to 79% DM (dry matter), fly ash from 75 to 82% DM, iron hydroxide sludge from 2.7 to 19% DM and biomass from 3 to 33% DM by electroosmosis....... The process was not optimised indicating that higher dry matter contents could be achieved by electroosmosis. It was possible to relate Casagrande's coefficient directly to the electroosmotic coefficient obtained by dewatering experiments....

A comparative study on real lab and simulation lab in communication engineering from students' perspectives

Science.gov (United States)

Balakrishnan, B.; Woods, P. C.

2013-05-01

Over the years, rapid development in computer technology has engendered simulation-based laboratory (lab) in addition to the traditional hands-on (physical) lab. Many higher education institutions adopt simulation lab, replacing some existing physical lab experiments. The creation of new systems for conducting engineering lab activities has raised concerns among educators on the merits and shortcomings of both physical and simulation labs; at the same time, many arguments have been raised on the differences of both labs. Investigating the effectiveness of both labs is complicated, as there are multiple factors that should be considered. In view of this challenge, a study on students' perspectives on their experience related to key aspects on engineering laboratory exercise was conducted. In this study, the Visual Auditory Read and Kinetic model was utilised to measure the students' cognitive styles. The investigation was done through a survey among participants from Multimedia University, Malaysia. The findings revealed that there are significant differences for most of the aspects in physical and simulation labs.

Digital computer control on Canadian nuclear power plants -experience to date and the future outlook

International Nuclear Information System (INIS)

Pearson, A.

1977-10-01

This paper discusses the performance of the digital computer control system at Pickering through the years 1973 to 1976. This evaluation is based on a study of the Pickering Generating Station operating records. The paper goes on to explore future computer architectures and the advantages that could accrue from a distributed system approach. Also outlined are the steps being taken to develop these ideas further in the context of two Chalk River projects - REDNET, an advanced data acquisition system being installed to process information from engineering experiments in NRX and NRU reactors, and CRIP, a prototype communications network using cable television technology. (author)

Muon tomography with momentum measurements for fast detection of nuclear materials at ports of entry

Energy Technology Data Exchange (ETDEWEB)

Erlandson, A.; Anghel, V. [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Armitage, J. [Carleton Univ., Physics Dept., Ottawa, Ontario (Canada); and others

2015-03-15

Muon tomography uses naturally occurring high energy cosmic ray particles called muons to statistically reconstruct 3D images of targets analogously to techniques widely used in medical physics. The Cosmic Ray Inspection and Passive Tomography (CRIPT) detector is a Canadian initiative that has demonstrated that the concept of tomography can be applied to cargo using cosmic ray muons. The unique aspect of the CRIPT detector is its use of muon momentum information which decreases the scanning time required to reconstruct an image. The CRIPT detector is currently operating at Atomic Energy of Canada Limited's (AECL) Chalk River Laboratories. (author)

Muon tomography with momentum measurements for fast detection of nuclear materials at ports of entry

International Nuclear Information System (INIS)

Erlandson, A.; Anghel, V.; Armitage, J.

2015-01-01

Muon tomography uses naturally occurring high energy cosmic ray particles called muons to statistically reconstruct 3D images of targets analogously to techniques widely used in medical physics. The Cosmic Ray Inspection and Passive Tomography (CRIPT) detector is a Canadian initiative that has demonstrated that the concept of tomography can be applied to cargo using cosmic ray muons. The unique aspect of the CRIPT detector is its use of muon momentum information which decreases the scanning time required to reconstruct an image. The CRIPT detector is currently operating at Atomic Energy of Canada Limited's (AECL) Chalk River Laboratories. (author)

Muon tomography with momentum measurements for fast detection of nuclear materials at ports of entry

International Nuclear Information System (INIS)

Erlandson, A.; Anghel, V.; Armitage, J.

2014-01-01

Muon tomography uses naturally occurring high energy cosmic ray particles called muons to statistically reconstruct 3D images of targets analogously to techniques widely used in medical physics. The Cosmic Ray Inspection and Passive Tomography (CRIPT) detector is a Canadian initiative that has demonstrated that the concept of tomography can be applied to cargo using cosmic ray muons. The unique aspect of the CRIPT detector is its use of muon momentum information which decreases the scanning time required to reconstruct an image. The CRIPT detector is currently operating at Atomic Energy of Canada Limited's (AECL) Chalk River Laboratories. (author)

Muon tomography with momentum measurements for fast detection of nuclear materials at ports of entry

Energy Technology Data Exchange (ETDEWEB)

Erlandson, A.; Anghel, V. [Atomic Energy of Canada Limited, Chalk River, ON (Canada); Armitage, J. [Carleton Univ., Physics Dept., Ottawa, ON (Canada); and others

2014-07-01

Muon tomography uses naturally occurring high energy cosmic ray particles called muons to statistically reconstruct 3D images of targets analogously to techniques widely used in medical physics. The Cosmic Ray Inspection and Passive Tomography (CRIPT) detector is a Canadian initiative that has demonstrated that the concept of tomography can be applied to cargo using cosmic ray muons. The unique aspect of the CRIPT detector is its use of muon momentum information which decreases the scanning time required to reconstruct an image. The CRIPT detector is currently operating at Atomic Energy of Canada Limited's (AECL) Chalk River Laboratories. (author)

Chemical speciation of radionuclides in contaminant plumes at the Chalk River Nuclear Laboratories

International Nuclear Information System (INIS)

Champ, D.R.

1986-01-01

Experimental disposals of liquid and glassified wastes directly into the sands of the Perch Lake basin, Ontario, Canada, have resulted in the formation of well-defined subsurface contaminant plumes in the groundwater flow system. Using large volume water sampling techniques we have detected low concentrations of several long-lived radionuclides including isotopes of Pu, Am, Cm, Tc, I, Sr and Cs. The particulate and ionic speciation results from these studies support the conclusions of previous laboratory column studies that transport of radionuclides, particularly Cs and Pu, on particulates and/or colloids could be a significant mobilization mechanism in groundwater flow systems. We also propose, based on a comparison of the plume data with previous detailed studies on 60 Co that complexation reactions with natural as well as synthetic organic ligands can yield mobile anionic species of the actinides and lanthanides. Further detailed studies will be required to support this postulate. (author)

X-ray measurement of residual stress in metals at Chalk River Nuclear Laboratories

International Nuclear Information System (INIS)

Winegar, J.E.

1980-06-01

X-ray diffraction is used at CRNL to measure residual stress in metals. This report summarizes the basic principles of stress measurement, and reviews factors affecting accuracy of measurement. The technique and equipment described were developed at CRNL to give reliable measurements. Accuracy of measurement is achieved by using fixed-count step-scanning and by computer analysis of intensity data using a cubic spline curve smoothing routine. Specific reference is made to the measurement of residual stress in Inconel-600 and Incoloy-800 boiler tubing. Because it measures stress in thin surface layers, the X-ray method can also be used to measure the depth profile of stresses. As there are no standardized procedures for measuring residual stress, this report will be useful both to those unfamiliar with the measurement of residual stress and to those already making such measurements in other laboratories. (auth)

Purification and solidification of reactor wastes at a Canadian nuclear generating station

International Nuclear Information System (INIS)

Buckley, L.P.; Burt, D.A.

1981-06-01

Chalk River Nuclear Laboratories are developing methods to condition power reactor wastes and to immobilize their radionuclides. Evaporation alone and combined with bituminization has been an important part of the program. After testing at the laboratories a 0.5 m 2 wiped-film evaporator was sent to the Douglas Point Nuclear Generating Station (220 MWe) to demonstrate its suitability to handle typical reactor liquid wastes. Two specific tasks undertaken with the wiped-film evaporator were successfully completed. The first was purification of contaminated heavy water which had leaked from the moderator circuit. The heavy water is normally recovered, cleaned by filters and ion-exchange resin and then upgraded by electrolysis. Cleaning the heavy water with the wiped-film evaporator produced better quality water for upgrading than had been achieved by any previous method and at much lower operating cost. The second task was to concentrate and immobilize a decontamination waste. The waste was generated from the decontamination of pump bowls used in the primary heat transport circuit. The simultaneous addition of the liquid waste and bitumen emulsion to the wiped-film evaporator produced a solid containing 30 wt% waste solids in a bitumen matrix. The volume reduction achieved was 16:1 based on the volumes of initial liquid waste and the final product generated. The quantity sent to storage was 20 times less than had the waste been immobilized in a cement matrix. The successful demonstration has resulted in a proposal to install a wiped-film evaporator at the station to clean heavy water and immobilize decontamination wastes. (author)

Virtual Reality Lab Assistant

Science.gov (United States)

Saha, Hrishikesh; Palmer, Timothy A.

1996-01-01

Virtual Reality Lab Assistant (VRLA) demonstration model is aligned for engineering and material science experiments to be performed by undergraduate and graduate students in the course as a pre-lab simulation experience. This will help students to get a preview of how to use the lab equipment and run experiments without using the lab hardware/software equipment. The quality of the time available for laboratory experiments can be significantly improved through the use of virtual reality technology.

Charpy V, an application in Mat lab

International Nuclear Information System (INIS)

Castillo M, J.A.; Torres V, M.

2003-01-01

The obtained results with the system Charpy V V 1 designed in Mat lab for the estimate of parameters of three mathematical models are shown. The adjustment of data is used to determine the fracture energy, the lateral expansion and the percentage of ductility of steels coming from the reactor vessels of Laguna Verde, Veracruz. The data come from test tubes type Charpy V of irradiated material and not irradiated. To verify our results they were compared with those obtained by General Electric of data coming from the Laguna Verde nuclear power plant. (Author)

Teaching aids for nuclear chemistry

International Nuclear Information System (INIS)

Atwood, C.H.

1994-01-01

This paper provides teachers with a set of resources to use in teaching modern nuclear chemistry in their classrooms. Included in the resources are references to recent articles on nuclear science, some preprints and abstracts of articles, ideas of where to go for help, lab experiments, and a videotape of simulated nuclear reactions

Compaction monitoring in the Ekofisk area Chalk Fields

International Nuclear Information System (INIS)

Menghini, M.L.

1989-01-01

In late Nov. 1984, the subsidence phenomenon was recognized in the Ekofisk field. To determine the magnitude and areal extent of the formation compaction, a program for measuring compaction with electric logging tools was initiated. Initial time-lapse surveys performed with cased-hole neutron tools indicated that reservoir compaction was occurring, but the accuracy of the determination of compaction rate was low. In addition to the cased-hole neutron survey, radioactive markers and a gamma ray (GR) detection tool were used to determine compaction rate in the reservoir more accurately and to determine whether compaction was occurring in the overburden. A program for implanting radioactive-marker bullets and subsequent monitoring with a four-detector GR tool was implemented. There are currently 13 wells equipped with radioactive markers in the compaction monitoring program. Compaction monitoring accuracy using the four-detector GR tool was found to depend on wellbore geometry, completion design, and radioactive-marker placement. This paper gives the results of the program to date and describes the operational procedures and analysis techniques used for compaction monitoring in the greater Ekofisk area chalk fields

Uranium series geochemistry in aquifers: quantification of transport mechanisms of uranium and daughter products: the chalk aquifer (Champagne, France)

International Nuclear Information System (INIS)

Hubert, A.

2005-09-01

With the increase of contaminant flux of radionuclides in surface environment (soil, river, aquifer...), there is a need to understand and model the processes that control the distribution of uranium and its daughter products during transport within aquifers. We have used U-series disequilibria as an analogue for the transport of uranium and its daughter products in aquifer to understand such mechanisms. The measurements of uranium ( 234 U et 238 U), thorium ( 230 Th et 232 Th), 226 Ra and 222 Rn isotopes in the solid and liquid phases of the chalk aquifer in Champagne (East of France) allows us to understand the processes responsible for fractionation within the uranium decay chain. Fractionations are induced by physical and chemical properties of the elements (leaching, adsorption) but also by radioactive properties (recoil effect during α-decay). For the first time a comprehensive sampling of the solid phase has been performed, allowing quantifying mechanisms responsible for the long term evolution of the aquifer. A non steady state 1D model has been developed which takes into account leaching, adsorption processes as well as radioactive filiation and α-recoil effect. Retardation coefficients have been calculated for uranium, thorium and radium. The aquifer is characterised by a double porosity, and the contribution of fracture and matrix porosity on the water/rock interaction processes has been estimated. (author)

View graph presentations of the sixth DOE industry/university/lab forum on robotics for environmental restoration and waste management

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-10-01

The mission of the Robotics Technology Development Program involves the following: develop robotic systems where justified by safety, cost, and/or efficiency arguments; integrate the best talent from National Labs, industry, and universities in focused teams addressing complex-wide problems; and involve customers in the identification and development of needs driven technologies. This presentation focuses on five areas. They are: radioactive tank waste remediation (Richland); mixed waste characterization, treatment, and disposal (Idaho Falls); decontamination and decommissioning (Morgantown); landfill stabilization (Savannah River); and contaminant plumes containment and remediation (Savannah River).

View graph presentations of the sixth DOE industry/university/lab forum on robotics for environmental restoration and waste management

International Nuclear Information System (INIS)

1995-10-01

The mission of the Robotics Technology Development Program involves the following: develop robotic systems where justified by safety, cost, and/or efficiency arguments; integrate the best talent from National Labs, industry, and universities in focused teams addressing complex-wide problems; and involve customers in the identification and development of needs driven technologies. This presentation focuses on five areas. They are: radioactive tank waste remediation (Richland); mixed waste characterization, treatment, and disposal (Idaho Falls); decontamination and decommissioning (Morgantown); landfill stabilization (Savannah River); and contaminant plumes containment and remediation (Savannah River)

Nuclear technology and beekeeping industry: much more than atoms and bees

International Nuclear Information System (INIS)

Rapisarda, Vicenzo M.; Hussein, Ana M.

2002-01-01

Argentine beekeeping industry is the first honey world exporter and the third honey world producer. At the present work, the authors try to show why nuclear technology is one of the best tools for beekeepers to reach health and quality standards required by national and international organisations. Irradiation from Cobalt 60 aim to fight against American foul brood, European foul brood and Chalk brood, besides it is such a good mechanism to degradate acaricides residuals in wax which were used in order to kill Varroa jacobsoni Oud. During the last 30 years, studies have demonstrated honey bees are wonderful sentinel species which represent an incomparable help to nuclear activity through environmental monitoring. Nuclear energy, health care, commercial affairs and environment meet together at Ezeiza Atomic Center, where many developments have been done and new projects are carried out. (author)

LabVIEW 8 student edition

CERN Document Server

Bishop, Robert H

2007-01-01

For courses in Measurement and Instrumentation, Electrical Engineering lab, and Physics and Chemistry lab. This revised printing has been updated to include new LabVIEW 8.2 Student Edition. National Instruments' LabVIEW is the defacto industry standard for test, measurement, and automation software solutions. With the Student Edition of LabVIEW, students can design graphical programming solutions to their classroom problems and laboratory experiments with software that delivers the graphical programming capabilites of the LabVIEW professional version. . The Student Edition is also compatible with all National Instruments data acquisition and instrument control hardware. Note: The LabVIEW Student Edition is available to students, faculty, and staff for personal educational use only. It is not intended for research, institutional, or commercial use. For more information about these licensing options, please visit the National Instruments website at (http:www.ni.com/academic/)

Five Decades of Achievement, Future Challenges in Focus at Ceremony Marking IAEA Labs Anniversary

International Nuclear Information System (INIS)

2012-01-01

Full text: In the 50 years since they opened, the IAEA's laboratories in Seibersdorf have improved the lives of millions of people through work using sophisticated scientific techniques, IAEA Director General Yukiya Amano said today at a ceremony to mark the anniversary. Work at the labs has made a difference in controlling animal diseases in more than 30 countries in Africa and Asia, and contributed to the development of hardier and more nutritious crops such as barley that can grow in the High Andes of Peru. Scientists at the labs have helped communities identify the best sources of underground water and ensure that this scarce resource is used effectively. They have worked on safe ways to preserve food, and provided vital technical support for cancer treatment and other medical uses of nuclear technology. New challenges abound in the present and the future, Director General Amano said. ''Member States want us to do more in almost all areas of nuclear applications. This includes climate-smart agriculture, with priority on helping countries to adapt to climate change while improving food security. It includes improving preparedness for responding to nuclear emergencies and especially for dealing with radiological contamination in food and agriculture.'' The Director General also said the IAEA would contribute more to controlling mosquitoes that transmit malaria by using techniques that, together with pest control programmes, have helped control other insects. IAEA scientists at the eight nuclear applications laboratories and the safeguards laboratories carry out research and development and provide technical services to the IAEA's 158 Member States. The labs also regularly host fellows and scientific visitors, with more than 2 000 benefiting from this opportunity to learn in the past 50 years. (IAEA)

Status Report and Research Plan for Cables Harvested from Crystal River Unit 3 Nuclear Generating Plant

Energy Technology Data Exchange (ETDEWEB)

Fifield, Leonard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-09-20

Harvested cables from operating or decommissioned nuclear power plants present an important opportunity to validate models, understanding material aging behavior, and validate characterization techniques. Crystal River Unit 3 Nuclear Generating Plant is a pressurized water reactor that was licensed to operate from 1976 to 2013. Cable segments were harvested and made available to the Light Water Reactor Sustainability research program through the Electric Power Research Institute. Information on the locations and circuits within the reactor from whence the cable segments came, cable construction, sourcing and installation information, and photographs of the cable locations prior to harvesting were provided. The cable variations provided represent six of the ten most common cable insulations in the nuclear industry and experienced service usage for periods from 15 to 42 years. Subsequently, these cables constitute a valuable asset for research to understand aging behavior and measurement of nuclear cables. Received cables harvested from Crystal River Unit 3 Nuclear Generating Plant consist of low voltage, insulated conductor surrounded by jackets in lengths from 24 to 100 feet each. Cable materials will primarily be used to investigate aging under simultaneous thermal and gamma radiation exposure. Each cable insulation and jacket material will be characterized in its as-received condition, including determination of the temperatures associated with endothermic transitions in the material using differential scanning calorimetry and dynamic mechanical analysis. Temperatures for additional thermal exposure aging will be selected following the thermal analysis to avoid transitions in accelerated laboratory aging that do not occur in field conditions. Aging temperatures above thermal transitions may also be targeted to investigate the potential for artifacts in lifetime prediction from rapid accelerated aging. Total gamma doses and dose rates targeted for each material

Study of a conceptual nuclear energy center at Green River, Utah: licensing considerations

International Nuclear Information System (INIS)

Dowdle, M.; Russell, R.; Zillman, D.

1982-04-01

This report examines the laws governing the location of a 9-unit nuclear energy center (NEC) near Green River, Utah. The time frame being considered for development of the conceptual NEC is from 1995 to 2013. Accordingly, the report is forced to speculate about some aspects of the plant, its site and its construction. Most of the report examines existing legal requirements for constructing an NEC. Where pertinent, changes in the law are discussed that would affect an NEC that is to be licensed in one or two decades. In general, no insurmountable legal problems exist that would prevent an NEC from being licensed at the Green River location. Several legal requirements pose significant concerns and would have to be faced before an NEC could be built. Among the major legal constraints are radiation protection, regulatory approval of financing, access to water, and local zoning restrictions. Two other constraints that involve legal matters are the wisdom of standardization of the units and the responsibility of the NEC builder to correct socio-economic impacts on the local area

TASCC newsletter volume 9 no. 6

Energy Technology Data Exchange (ETDEWEB)

Thomson, L

1995-06-01

A newsletter produced by Chalk River`s Tandem Accelerator Superconducting Cyclotron Facility. Included in this June issue of TASCC is an update of the facility, TASCC workshop on international success and a listing of Junes`s experiments. 1 fig.

Technical evaluation of RETS-required reports for Crystal River Nuclear Generating Plant, Unit 3, for 1983

International Nuclear Information System (INIS)

Magleby, E.H.; Young, T.E.

1985-01-01

A review was performed on the reports required by Federal regulations and the plant-specific Radiological Effluent Technical Specifications (RETS) for operations conducted at Florida Power Corporation's Crystal River Nuclear Plant, Unit 3, during 1983. The three periodic reports reviewed were (1) the Effluent and Waste Disposal Semiannual Report, January 1-June 30, 1983, (2) the Effluent and Waste Disposal Semiannual Report, July 1-December 31, 1983, and (3) the Annual Environmental Operating Report, Radiological, 1983. The principal review guidelines were the plant's specific RETS and NRC guidance given in NUREG-0133, ''Preparation of Radiological Effluent Technical Specifications for Nuclear Power Plants.'' The Licensee's submitted reports were found to be reasonably complete and consistent with the review guidelines

CRL research reactor diesel generator reliability study 1960 - 1992

International Nuclear Information System (INIS)

Winfield, D.J.; McCauley, G.M.

1994-07-01

A data base has been provided for the Chalk River Laboratories (CRL) research reactor diesel generator reliability, for use in risk assessment studies of CRL research reactors. Data from 1960 to end of 1992 have been collected, representing 358 diesel generator years of experience. The data is used to provide failure-to-start probabilities and failure-to-run rates. Data is also classified according to subsystem failures, multiple failures and common cause failures. Comparisons with other recent studies of nuclear power plant diesel generator reliability have been made. This revision updates the 1989 September report. (author). 14 refs., 13 tabs., 10 figs

Vibrational motions in rotating nuclei studied by Coulomb excitations

Energy Technology Data Exchange (ETDEWEB)

Shimizu, Yoshifumi R [Kyushu Univ., Fukuoka (Japan). Dept. of Physics

1998-03-01

As is well-known Coulomb excitation is an excellent tool to study the nuclear collective motions. Especially the vibrational excitations in rotating nuclei, which are rather difficult to access by usual heavy-ion fusion reactions, can be investigated in detail. Combined with the famous 8{pi}-Spectrometer, which was one of the best {gamma}-ray detector and had discovered some of superdeformed bands, such Coulomb excitation experiments had been carried out at Chalk River laboratory just before it`s shutdown of physics division. In this meeting some of the experimental data are presented and compared with the results of theoretical investigations. (author)

Computer-aided control system design

International Nuclear Information System (INIS)

Lebenhaft, J.R.

1986-01-01

Control systems are typically implemented using conventional PID controllers, which are then tuned manually during plant commissioning to compensate for interactions between feedback loops. As plants increase in size and complexity, such controllers can fail to provide adequate process regulations. Multivariable methods can be utilized to overcome these limitations. At the Chalk River Nuclear Laboratories, modern control systems are designed and analyzed with the aid of MVPACK, a system of computer programs that appears to the user like a high-level calculator. The software package solves complicated control problems, and provides useful insight into the dynamic response and stability of multivariable systems

Measurement of enriched uranium and uranium-aluminum fuel materials with the AWCC

International Nuclear Information System (INIS)

Krick, M.S.; Menlove, H.O.; Zick, J.; Ikonomou, P.

1985-05-01

The active well coincidence counter (AWCC) was calibrated at the Chalk River Nuclear Laboratories (CRNL) for the assay of 93%-enriched fuel materials in three categories: (1) uranium-aluminum billets, (2) uranium-aluminum fuel elements, and (3) uranium metal pieces. The AWCC was a standard instrument supplied to the International Atomic Energy Agency under the International Safeguards Project Office Task A.51. Excellent agreement was obtained between the CRNL measurements and previous Los Alamos National Laboratory measurements on similar mockup fuel material. Calibration curves were obtained for each sample category. 2 refs., 8 figs., 15 tabs

Demise of Texas collider has made Europe's lab a magnet for scientists

CERN Multimedia

Siegfried, Tom

2004-01-01

Had U.S. politics and science meshed more favorably, physicists from around the world would now be flocking to Waxahachie. The defunct Superconducting Super Collider (SSC) should by now have been smashing atoms, but now Europe's top nuclear research lab offers a more picturesque world capital of physics that the prairie south of Dallas

Sister Lab Program Prospective Partner Nuclear Profile: Indonesia

International Nuclear Information System (INIS)

Bissani, M; Tyson, S

2006-01-01

Indonesia has participated in cooperative technical programs with the IAEA since 1957, and has cooperated with regional partners in all of the traditional areas where nuclear science is employed: in medicine, public health (such as insect control and eradication programs), agriculture (e.g. development of improved varieties of rice), and the gas and oil industries. Recently, Indonesia has contributed significantly to the Reduced Enrichment Research and Training Reactor (RERTR) Program by conducting experiments to confirm the feasibility of Mo-99 production using high-density low enriched uranium (LEU) fuel, a primary goal of the RERTR Program. Indonesia's first research reactor, the TRIGA Mark II at Bandung, began operation in 1964 at 250 kW and was subsequently upgraded in 1971 to 1 MW and further upgraded in 2000 to 2 MW. This reactor was joined by another TRIGA Mark II, the 100-kW Kartini-PPNY at Yogyakarta, in 1979, and by the 30-MW G.A. Siwabessy multipurpose reactor in Serpong, which achieved criticality in July 1983. A 10-MW radioisotope production reactor, to be called the RPI-10, also was proposed for construction at Serpong in the late 1990s, but the project apparently was not carried out. In the five decades since its nuclear research program began, Indonesia has trained a cadre of scientific and technical staff who not only operate and conduct research with the current facilities, but also represent the nucleus of a skilled labor pool to support development of a nuclear power program. Although Indonesia's previous on-again, off-again consideration of nuclear power has not gotten very far in the past, it now appears that Indonesia again is giving serious consideration to beginning a national nuclear energy program. In June 2006, Research and Technology Minister Kusmayanto Kadiman said that his ministry was currently putting the necessary procedures in place to speed up the project to acquire a nuclear power plant, indicating that, ''We will need around

Why x-ray chests

International Nuclear Information System (INIS)

Evans, D.W.S.

1979-06-01

In order to assess the validity of screening chest radiography at Chalk River Nuclear Laboratories, the yield of occult major disease and its significance to the afflicted employees have been examined over a ten year period. The study suggests that the incidence rate of occult disease which in retrospect proved to have been of major or life-threatening importance to the afflicted employee approximates 1 per 1000 population per annum. Major benefit accrued only to about 1 in 3 of these employees, the remainder gaining little more than that which would have followed treatment had their diseases presented symptomatically. These results are considered in relation to the health surveillance needs of a population generally and selectively exposed to diverse health hazards within the nuclear industry. (auth)

Software development for continuous-gas-flow AMS

International Nuclear Information System (INIS)

Reden, K.F. von; Roberts, M.L.; Jenkins, W.J.; Rosenheim, B.E.; McNichol, A.P.; Schneider, R.J.

2008-01-01

The National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) Facility at Woods Hole Oceanographic Institution is presently completing installation of a novel continuous-flow AMS system. A multi-year development of an AMS microwave gas ion source in collaboration with Atomic Energy Canada Limited (AECL), Chalk River, has preceded this final step of an implementation that is expected to add a new dimension to 14 C AMS. National Instruments, NIM, and CAMAC modules have been programmed with LabVIEW on a Windows XP platform to form the basis for data acquisition. In this paper we discuss possible applications and include simulations of expected data acquisition scenarios like real-time AMS analysis of chromatograms. Particular attention will have to be given to issues of synchronization between rapidly changing input amplitudes and signal processing cycles in hardware and software

Lab at Home: Hardware Kits for a Digital Design Lab

Science.gov (United States)

Oliver, J. P.; Haim, F.

2009-01-01

An innovative laboratory methodology for an introductory digital design course is presented. Instead of having traditional lab experiences, where students have to come to school classrooms, a "lab at home" concept is proposed. Students perform real experiments in their own homes, using hardware kits specially developed for this purpose. They…

Biogen water of the Irtysh river - the principal population health factor suffered from the nuclear test on the Semipalatinsk test site

International Nuclear Information System (INIS)

Inyushin, V.M.; Yurenkov, V.V.

2001-01-01

Authors notes, that Semipalatinsk test site activity together with other factors changes a water quality. The principal consequence of nuclear tests is build up in new cells by the 'pathogenous' water in plants, animals and human . 'Pathogenous water' is generating at steady changes of electronic strictures (spin performances) at ionizing radiation effect, radionuclides and other factors of nuclear explosions. These factors were did not known to a world-wide science. The second of very important phenomenon of nuclear explosions consequences at the Semipalatinsk test site is reduce of the hydro-plasma in the water sources the Irtysh River basin. This was proved with direct studies microcurrents density in the water as well as analysis of electronic and ionic structures with the plasma-graphic help. The water having the pathogenous memory - building up in the cells - reduces the immune status, negatively reflects on the vital functions, decreasing the resistance to unfavorable effects. It is offered for remediation of the 'pathogenous water' to use the bio-genized water as most adequate one to endogenous water of living cells. Mass usage of the bio-genized water takes out genetic consequences of nuclear explosions and increase of an immunity level. The 'Bio-genization' of the Irtysh River water is concludes a few stages

Labs not in a lab: A case study of instructor and student perceptions of an online biology lab class

Science.gov (United States)

Doiron, Jessica Boyce

Distance learning is not a new phenomenon but with the advancement in technology, the different ways of delivering an education have increased. Today, many universities and colleges offer their students the option of taking courses online instead of sitting in a classroom on campus. In general students like online classes because they allow for flexibility, the comfort of sitting at home, and the potential to save money. Even though there are advantages to taking online classes, many students and instructors still debate the effectiveness and quality of education in a distant learning environment. Many universities and colleges are receiving pressure from students to offer more and more classes online. Research argues for both the advantages and disadvantages of online classes and stresses the importance of colleges and universities weighing both sides before deciding to adopt an online class. Certain classes may not be suitable for online instruction and not all instructors are suitable to teach online classes. The literature also reveals that there is a need for more research on online biology lab classes. With the lack of information on online biology labs needed by science educators who face the increasing demand for online biology labs, this case study hopes to provide insight into the use of online biology lab classes and the how students and an instructor at a community college in Virginia perceive their online biology lab experience as well as the effectiveness of the online labs.

Stylolites, porosity, depositional texture, and silicates in chalk facies sediments

DEFF Research Database (Denmark)

Fabricius, Ida Lykke; Borre, Mai K.

2007-01-01

dissolution around 490 m below sea floor (bsf) corresponds to an interval of waning porosity-decline, and even the occurrence of proper stylolites from 830 m bsf is accompanied by only minor porosity reduction. Because opal is present, the pore-water is relatively rich in Si which through the formation of Ca......-silica complexes causes an apparent super-saturation of Ca and retards cementation. The onset of massive pore-filling cementation at 1100 m bsf may be controlled by the temperature-dependent transition from opal-CT to quartz. In the stylolite-bearing chalk of two wells in the Gorm and Tyra fields, the nannofossil...... matrix shows recrystallization but only minor pore-filling cement, whereas microfossils are cemented. Cementation in Gorm and Tyra is thus partial and has apparently not been retarded by opal-controlled pore-water. A possible explanation is that, due to the relatively high temperature, silica has...

PD Lab

Directory of Open Access Journals (Sweden)

Marcel Bilow

2015-08-01

Full Text Available PD Lab explores the applications of building sector related product development.  PD lab investigates and tests digital production technologies like CNC milled wood connections. It will also act as a platform in its wider meaning to investigate the effects and influences of file to factory production, to explore the potential in the field of sustainability, material use, logistics and the interaction of stakeholders within the chain of the building process.

MatLab Script and Functional Programming

Science.gov (United States)

Shaykhian, Gholam Ali

2007-01-01

MatLab Script and Functional Programming: MatLab is one of the most widely used very high level programming languages for scientific and engineering computations. It is very user-friendly and needs practically no formal programming knowledge. Presented here are MatLab programming aspects and not just the MatLab commands for scientists and engineers who do not have formal programming training and also have no significant time to spare for learning programming to solve their real world problems. Specifically provided are programs for visualization. The MatLab seminar covers the functional and script programming aspect of MatLab language. Specific expectations are: a) Recognize MatLab commands, script and function. b) Create, and run a MatLab function. c) Read, recognize, and describe MatLab syntax. d) Recognize decisions, loops and matrix operators. e) Evaluate scope among multiple files, and multiple functions within a file. f) Declare, define and use scalar variables, vectors and matrices.

Process-based modelling to evaluate simulated groundwater levels and frequencies in a Chalk catchment in south-western England

Science.gov (United States)

Brenner, Simon; Coxon, Gemma; Howden, Nicholas J. K.; Freer, Jim; Hartmann, Andreas

2018-02-01

Chalk aquifers are an important source of drinking water in the UK. Due to their properties, they are particularly vulnerable to groundwater-related hazards like floods and droughts. Understanding and predicting groundwater levels is therefore important for effective and safe water management. Chalk is known for its high porosity and, due to its dissolvability, exposed to karstification and strong subsurface heterogeneity. To cope with the karstic heterogeneity and limited data availability, specialised modelling approaches are required that balance model complexity and data availability. In this study, we present a novel approach to evaluate simulated groundwater level frequencies derived from a semi-distributed karst model that represents subsurface heterogeneity by distribution functions. Simulated groundwater storages are transferred into groundwater levels using evidence from different observations wells. Using a percentile approach we can assess the number of days exceeding or falling below selected groundwater level percentiles. Firstly, we evaluate the performance of the model when simulating groundwater level time series using a spilt sample test and parameter identifiability analysis. Secondly, we apply a split sample test to the simulated groundwater level percentiles to explore the performance in predicting groundwater level exceedances. We show that the model provides robust simulations of discharge and groundwater levels at three observation wells at a test site in a chalk-dominated catchment in south-western England. The second split sample test also indicates that the percentile approach is able to reliably predict groundwater level exceedances across all considered timescales up to their 75th percentile. However, when looking at the 90th percentile, it only provides acceptable predictions for long time periods and it fails when the 95th percentile of groundwater exceedance levels is considered. By modifying the historic forcings of our model

Exploring linear algebra labs and projects with Mathematica

CERN Document Server

Arangala, Crista

2014-01-01

Matrix Operations Lab 0: An Introduction to Mathematica Lab 1: Matrix Basics and Operations Lab 2: A Matrix Representation of Linear Systems Lab 3: Powers, Inverses, and Special Matrices Lab 4: Graph Theory and Adjacency Matrices Lab 5: Permutations and Determinants Lab 6: 4 x 4 Determinants and Beyond Project Set 1 Invertibility Lab 7: Singular or Nonsingular? Why Singularity Matters Lab 8: Mod It Out, Matrices with Entries in ZpLab 9: It's a Complex World Lab 10: Declaring Independence: Is It Linear? Project Set 2 Vector Spaces Lab 11: Vector Spaces and SubspacesLab 12: Basing It All on Just a Few Vectors Lab 13: Linear Transformations Lab 14: Eigenvalues and Eigenspaces Lab 15: Markov Chains, An Application of Eigenvalues Project Set 3 Orthogonality Lab 16: Inner Product Spaces Lab 17: The Geometry of Vector and Inner Product SpacesLab 18: Orthogonal Matrices, QR Decomposition, and Least Squares Regression Lab 19: Symmetric Matrices and Quadratic Forms Project Set 4 Matrix Decomposition with Applications L...

An MCNP parametric study of George C. Laurence's subcritical pile experiment

International Nuclear Information System (INIS)

Dranga, R.; Blomeley, L.; Carrington, R.

2014-01-01

In the early 1940s at the National Research Council (NRC) Laboratories in Ottawa, Canada, Dr. George Laurence conducted several experiments to determine if a sustained nuclear fission chain reaction in a carbon-uranium arrangement (or 'pile') was possible. Although Dr. Laurence did not achieve criticality, these pioneering experiments marked a significant historical event in nuclear science, and they provided a valuable reference for subsequent experiments that led to the design of Canada's first heavy-water reactors at the Chalk River Nuclear Laboratories. This paper summarizes the results of a recent collaborative project between Atomic Energy of Canada Limited and the Deep River Science Academy undertaken to numerically explore the experiments carried out at the NRC Laboratories by Dr. Laurence, while teaching high school students about nuclear science and technology. In this study, a modern Monte Carlo reactor physics code, MCNP6, was utilized to identify and study the key parameters impacting the subcritical pile's neutron multiplication factor (e.g., moderation, geometry, material impurities) and quantify their effect on the extent of subcriticality. The findings presented constitute the first endeavour to model, using a current computational reactor physics tool, the seminal experiment that provided the foundation of Canada's nuclear science and technology program. (author)

An MCNP parametric study of George C. Laurence's subcritical pile experiment

Energy Technology Data Exchange (ETDEWEB)

Dranga, R.; Blomeley, L., E-mail: ruxandra.dranga@cnl.ca [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Carrington, R. [McGill Univ., Dept. of Mathematics and Statistics, Montreal, Quebec (Canada)

2014-12-01

In the early 1940s at the National Research Council (NRC) Laboratories in Ottawa, Canada, Dr. George Laurence conducted several experiments to determine if a sustained nuclear fission chain reaction in a carbon-uranium arrangement (or 'pile') was possible. Although Dr. Laurence did not achieve criticality, these pioneering experiments marked a significant historical event in nuclear science, and they provided a valuable reference for subsequent experiments that led to the design of Canada's first heavy-water reactors at the Chalk River Nuclear Laboratories. This paper summarizes the results of a recent collaborative project between Atomic Energy of Canada Limited and the Deep River Science Academy undertaken to numerically explore the experiments carried out at the NRC Laboratories by Dr. Laurence, while teaching high school students about nuclear science and technology. In this study, a modern Monte Carlo reactor physics code, MCNP6, was utilized to identify and study the key parameters impacting the subcritical pile's neutron multiplication factor (e.g., moderation, geometry, material impurities) and quantify their effect on the extent of subcriticality. The findings presented constitute the first endeavour to model, using a current computational reactor physics tool, the seminal experiment that provided the foundation of Canada's nuclear science and technology program. (author)

TASCC newsletter volume 7 no. 11

Energy Technology Data Exchange (ETDEWEB)

Thomson, L

1993-11-01

A newsletter produced by Chalk River`s Tandem Accelerator Superconducting Cyclotron Facility. Included in this November issue of TASCC is an update of the facility, news of a purchase of phase-shifters and a listing of experiments run in November. 2 figs.

TASCC newsletter volume 7 no. 12

Energy Technology Data Exchange (ETDEWEB)

Thomson, L

1993-12-01

A newsletter produced by Chalk River`s Tandem Accelerator Superconducting Cyclotron Facility. Included in this December issue of TASCC is an update of the facility, a year end review by the director and a listing of experiments carried out in December. 3 figs.

TASCC newsletter volume 8 no. 7

Energy Technology Data Exchange (ETDEWEB)

Thomson, L

1994-07-01

A newsletter produced by Chalk River`s Tandem Accelerator Superconducting Cyclotron Facility. Included in this July issue of TASCC is an update of the facility,news on TASCC personnel, results of a coulomb-excitation and a listing of July`s experiments. 4 figs.

TASCC newsletter volume 9 no. 4

Energy Technology Data Exchange (ETDEWEB)

Thomson, L

1995-04-01

A newsletter produced by Chalk River`s Tandem Accelerator Superconducting Cyclotron Facility. Included in this April issue of TASCC is an update of the facility, analysis of Chernobyl samples, staff changes, Internet availability and a listing of April`s experiments. 1 fig.

TASCC newsletter volume 9 no. 12

Energy Technology Data Exchange (ETDEWEB)

Thomson, L

1995-12-01

A newsletter produced by Chalk River`s Tandem Accelerator Superconducting Cyclotron Facility. Included in this December issued of TASCC is an update of the facility, a year -end review of TASCC by the director and a listing of December`s experiments. 1 fig.

US-Russian laboratory-to-laboratory cooperation in nuclear materials protection, control, and accounting

International Nuclear Information System (INIS)

Mullen, M.; Augustson, R.; Horton, R.

1995-01-01

Under the guidance of the Department of Energy (DOE), six DOE laboratories have initiated a new program of cooperation with the Russian Federation's nuclear institutes. The purpose of the program is to accelerate progress toward a common goal shared by both the US and Russia--to reduce the risks of nuclear weapons proliferation, including such threats as theft, diversion, and unauthorized possession of nuclear materials, by strengthening systems of nuclear materials protection, control, and accounting. This new program is called the Laboratory-to-Laboratory Nuclear Materials Protection, Control, and Accounting (Lab-to-Lab MPC and A) Program. It is designed to complement other US-Russian MPC and A programs such as the government-to-government (Nunn-Lugar) programs. The Lab-to-Lab MPC and A program began in 1994 with pilot projects at two sites: Arzamas-16 and the Kurchitov Institute. This paper presents an overview of the Laboratory-to-Laboratory MPC and A Program. It describes the background and need for the program; the objectives and strategy; the participating US and Russian laboratories, institutes and enterprises; highlights of the technical work; and plans for the next several years

Upper Cretaceous chalk facies and depositional history recorded in the Mona-1 core, Mona Ridge

DEFF Research Database (Denmark)

Anderskouv, Kresten; Surlyk, Finn

2011-01-01

, including mudflow, debris flow, and slumping. Pelagic deposits vary mainly in terms of the concentration of siliciclastic material, the trace-fossil assemblage, and the presence or ab­sence of primary sedimentary structures. Pelagic sedimentation was probably punctuated by the deposition of thin turbidites...... slump packages (14–18 in total) are interpreted, forming over 40% of the succession; debrites appear to be the most common precursor facies involved in slumping. The vertical succession of facies records an earliest Cenomanian facies shift from dominantly siliciclastic to chalk deposition...

Trace fossils of a cyclic chalk-marl succession; the upper Maastrichtian Rørdal Member, Denmark

DEFF Research Database (Denmark)

Lauridsen, Bodil Wesenberg; Surlyk, Finn; Bromley, Richard Granville

2011-01-01

Trace fossils from an upper Maastrichtian cyclic chalk–marl succession, the Rørdal Member, exposed in the Rørdal quarry, Denmark, are analysed in order to test whether the changes in substrate lithology exerted any control over the ichnodiversity, tiering complexity, and density of the infauna...... in the visibility of traces between chalk and marl and not due to differences in ecological stress upon the endobenthic community of the two lithologies. The study thus provides an excellent example of how the effect of taphonomic factors may give a misleading and biased impression of apparent differences...

Improving the Quality of Lab Reports by Using Them as Lab Instructions

Science.gov (United States)

Haagen-Schuetzenhoefer, Claudia

2012-10-01

Lab exercises are quite popular in teaching science. Teachers have numerous goals in mind when teaching science laboratories. Nevertheless, empirical research draws a heterogeneous picture of the benefits of lab work. Research has shown that it does not necessarily contribute to the enhancement of practical abilities or content knowledge. Lab activities are frequently based on recipe-like, step-by-step instructions ("cookbook style"), which do not motivate students to engage cognitively. Consequently, students put the emphasis on "task completion" or "manipulating equipment."2

Learning from history: A case study in nuclear fuel

International Nuclear Information System (INIS)

Robertson, J.A.L.

1996-01-01

The award of the 1993 W.J. Kroll Zirconium Medal recognized the value of cooperative, multidisciplinary, applied research in tackling practical problems. This paper suggests that several other lessons relevant to the current debate on science-and-technology (S and T) policy can be drawn from experience a quarter of a century ago. It outlines how close cooperation among those involved with the fuel for the Canadian CANDU heavy-water reactors identified a problem, then proceeded to solve it expeditiously. This capability for a rapid response to an unforeseen problem was no accident, but arose out of the conditions that existed at the Chalk River Laboratory of Atomic Energy of Canada Limited (AECL) and a deliberate policy to maintain this capability even when the utility's power reactors were demonstrating excellent performance

Problems and solutions in application of IEEE standards at Savannah River Site, Department of Energy (DOE) nuclear facilities

International Nuclear Information System (INIS)

Lee, Y.S.; Bowers, T.L.; Chopra, B.J.; Thompson, T.T.; Zimmerman, E.W.

1993-01-01

The Department of Energy (DOE) Nuclear Material Production Facilities at the Savannah River Site (SRS) were designed, constructed, and placed into operation in the early 1950's, based on existing industry codes/standards, design criteria, analytical procedures. Since that time, DOE has developed Orders and Polices for the planning, design and construction of DOE Nuclear Reactor Facilities which invoke or reference commercial nuclear reactor codes and standards. The application of IEEE reactor design requirements such as Equipment Qualification, Seismic Qualification, Single Failure Criteria, and Separation Requirement, to non-reactor facilities has been a problem since the IEEE reactor criteria do not directly confirm to the needs of non-reactor facilities. SRS Systems Engineering is developing a methodology for the application of IEEE Standards to non-reactor facilities at SRS

Design basis flood for nuclear power plants on river sites

International Nuclear Information System (INIS)

1983-01-01

The Guide presents techniques for determining the design basis flood (DBF) to be used for siting nuclear power plants at or near non-tidal reaches of rivers and for protecting nuclear power plants against floods. Since flooding of a nuclear power plant can have repercussions on safety, the DBF is always chosen to have a very low probability of exceedance per annum. The DBF may result from one or more of the following causes: (1) Precipitation, snowmelt; (2) Failure of water control structures, either from seismic or hydrological causes or from faulty operation of these structures; (3) Channel obstruction such as landslide, ice effects, log or debris jams, and effects of vulcanism. Normally the DBF is not less than any recorded or historical flood occurrence. For flood evaluation two types of methods are discussed in this Guide: probabilistic and deterministic. Simple probabilistic methods to determine floods of such low exceedance probability have a great degree of uncertainty and are presented for use only during the site survey. However, the more sophisticated probabilistic methods, the so-called stochastic methods, may give an acceptable result, as outlined in this Guide. The preferred method of evaluating the component of the DBF due to precipitation, as described in this Guide, is the deterministic one, based on the concept of a limit to the probable maximum precipitation (PMP) and on the unit hydrograph technique. Dam failures may generate a flood substantially more severe than that due to precipitation. The methodology for evaluating these types of floods is therefore presented in this Guide. Making allowance for the possible simultaneous occurrence of two or more important flood-producing events is also discussed here. The Guide does not deal with floods caused by sabotage

Used nuclear materials at Savannah River Site: asset or waste?

International Nuclear Information System (INIS)

Magoulas, Virginia

2013-01-01

The nuclear industry, both in the commercial and the government sectors, has generated large quantities of material that span the spectrum of usefulness, from highly valuable ''assets'' to worthless ''wastes''. In many cases, the decision parameters are clear. Transuranic waste and high level waste, for example, have no value, and is either in a final disposition path today, or - in the case of high level waste - awaiting a policy decision about final disposition. Other materials, though discardable, have intrinsic scientific or market value that may be hidden by the complexity, hazard, or cost of recovery. An informed decision process should acknowledge the asset value, or lack of value, of the complete inventory of materials, and the structure necessary to implement the range of possible options. It is important that informed decisions are made about the asset value for the variety of nuclear materials available. For example, there is a significant quantity of spent fuel available for recycle (an estimated $4 billion value in the Savannah River Site's (SRS) L area alone); in fact, SRS has already blended down more than 300 metric tons of uranium for commercial reactor use. Over 34 metric tons of surplus plutonium is also on a path to be used as commercial fuel. There are other radiological materials that are routinely handled at the site in large quantities that should be viewed as strategically important and / or commercially viable. In some cases, these materials are irreplaceable domestically, and failure to consider their recovery could jeopardize our technological leadership or national defense. The inventories of nuclear materials at SRS that have been characterized as ''waste'' include isotopes of plutonium, uranium, americium, and helium. Although planning has been performed to establish the technical and regulatory bases for their discard and disposal, recovery of these materials is both economically attractive and in the national interest.

Reforming Cookbook Labs

Science.gov (United States)

Peters, Erin

2005-01-01

Deconstructing cookbook labs to require the students to be more thoughtful could break down perceived teacher barriers to inquiry learning. Simple steps that remove or disrupt the direct transfer of step-by-step procedures in cookbook labs make students think more critically about their process. Through trials in the author's middle school…

The Portuguese Contribution for lab2go - pt.lab2go

Directory of Open Access Journals (Sweden)

Maria Teresa Restivo

2013-01-01

Full Text Available Online experimentation provides innovative and valuable tools for use in academy, in high schools, in industry and in medical areas. It has also become a precious tool for educational and training purposes in any of those areas. Looking at online experimentation as a pure distance learning tool it represents a very efficient way of sharing hands-on capabilities, for example with developing countries. In Portugal a new consortium of online experimentation was created for fostering the national potential, using the Portuguese version of lab2go web platform, pt.lab2go. The authors pretend to demonstrate some of capabilities of the consortium in sharing online labs.

TASCC newsletter volume 8 no. 4

Energy Technology Data Exchange (ETDEWEB)

Thomson, L

1994-04-01

A newsletter produced by Chalk River`s Tandem Accelerator Superconducting Cyclotron Facility. Included in this April issue of TASCC is an update of the facility, news on the Penning-trap spectrometer, educators at CRL, AECB inspection and a listing of April`s experiments. 1 fig.

Diagenesis of silica-rich mounded chalk, the Coniacian Arnager Limestone, Denmark

DEFF Research Database (Denmark)

Buus Madsen, Heine; Stemmerik, Lars; Surlyk, Finn

2010-01-01

The Coniacian Arnager Limestone Formation is exposed on the Danish island of Bornholm in the Baltic Sea. It is composed of mound-bedded siliceous chalk, and X-ray diffraction and scanning electron microscopy indicate a content of 30-70% insoluble minerals, including authigenic opal-CT, quartz......, clinoptilolite, feldspars, calcite, dolomite, and barite. Opal-CT and clinoptilolite are the most common and constitute 16-53% and 2-9%, respectively. The content of insoluble minerals varies laterally bothwithinthemounds and inplanar beds, and the opal-CT content varies by up to 10% vertically. Themounds...... precipitation of opal-CT. The opal-CT formed at temperatures around 17°C, the precipitation lowered the silica activity and the Si/Al ratio of the pore water, resulting in precipitation of clinoptilolite, feldspar and smectite. Calcite formed synchronouslywith the latest clinoptilolite.Minoramounts of quartz...

LabVIEW Support at CERN

CERN Multimedia

HR Department

2010-01-01

Since the beginning of 2009, due to the CERN restructuring, LabVIEW support moved from the IT to the EN department, joining the Industrial Controls and Electronics Group (ICE). LabVIEW support has been merged with the Measurement, Test and Analysis (MTA) section which, using LabVIEW, has developed most of the measurement systems to qualify the LHC magnets and components over the past 10 years. The post mortem analysis for the LHC hardware commissioning has also been fully implemented using LabVIEW, customised into a framework, called RADE, for CERN needs. The MTA section has started with a proactive approach sharing its tools and experience with the CERN LabVIEW community. Its framework (RADE) for CERN integrated application development has been made available to the users. Courses on RADE have been integrated into the standard National Instruments training program at CERN. RADE and LabVIEW support were merged together in 2010 on a single email address:labview.support@cern.ch For more information please...

Size effect of added LaB6 particles on optical properties of LaB6/Polymer composites

International Nuclear Information System (INIS)

Yuan Yifei; Zhang Lin; Hu Lijie; Wang Wei; Min Guanghui

2011-01-01

Modified LaB 6 particles with sizes ranging from 50 nm to 400 nm were added into polymethyl methacrylate (PMMA) matrix in order to investigate the effect of added LaB 6 particles on optical properties of LaB 6 /PMMA composites. Method of in-situ polymerization was applied to prepare PMMA from raw material—methyl methacrylate (MMA), a process during which LaB 6 particles were dispersed in MMA. Ultraviolet–visible–near infrared (UV–vis–NIR) absorption spectrum was used to study optical properties of the as-prepared materials. The difference in particle size could apparently affect the composites' absorption of visible light around wavelength of 600 nm. Added LaB 6 particles with size of about 70 nm resulted in the best optical properties among these groups of composites. - Graphical abstract: 70 nm LaB 6 particles resulted in the best performance on absorption of VIS and NIR, which could not be apparently achieved by LaB 6 particles beyond nano-scale. Highlights: ► LaB 6 /PMMA composites were prepared using the method of in-situ polymerization. ► LaB 6 particles added in MMA prolonged the time needed for its pre-polymerization. ► Nanosized LaB 6 particles could obviously absorb much NIR but little VIS.

Importance of small fishes and invasive crayfish in otter Lutra lutra diet in an English chalk stream

OpenAIRE

Britton, J.R.; Berry, M.; Sewell, S.; Lees, C.; Reading, P.

2017-01-01

The diet composition of the European otter Lutra lutra was assessed using spraint analysis in the Hampshire Avon, a lowland chalk stream in Southern England, over an 18-month period. Small cyprinid fishes were the main prey item taken in all seasons, with bullhead Cottus gobio and stone loach Barbatula barbatula also important; there were relatively few larger fishes of interest to fisheries found. There were significant seasonal differences in diet composition by season, with signal crayfish...

Socio-economic impacts of nuclear generating stations: Crystal River Unit 3 case study

International Nuclear Information System (INIS)

Bergmann, P.A.

1982-07-01

This report documents a case study of the socio-economic impacts of the construction and operation of the Crystal River Unit 3 nuclear power station. It is part of a major post-licensing study of the socio-economic impacts at twelve nuclear power stations. The case study covers the period beginning with the announcement of plans to construct the reactor and ending in the period 1980 to 1981. The case study deals with changes in the economy, population, settlement patterns and housing, local government and public services, social structure, and public response in the study area during the construction/operation of the reactor. A regional modeling approach is used to trace the impact of construction/operation on the local economy, labor market, and housing market. Emphasis in the study is on the attribution of socio-economic impacts to the reactor or other causal factors. As part of the study of local public response to the construction/operation of the reactor, the effects of the Three Mile Island accident are examined

Microbial Fluid-Rock Interactions in Chalk Samples and Salinity Factor in Divalent Ca2+ ions Release for Microbial Enhanced Oil Recovery Purposes

DEFF Research Database (Denmark)

Jimoh, Ismaila Adetunji; Rudyk, Svetlana Nikolayevna; Søgaard, Erik Gydesen

2011-01-01

In this study, laboratory experiments were performed on chalk samples from Danish sector of the North Sea to study microbial fluid-rock interactions with carbonate rock and to evaluate the dissolution of rock matrix (CaCO3). Result showed that the average concentration of Ca2+ ions after microbia...

Wind River Watershed Restoration Project, Segment II, 2000-2002 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Bair, Brian; Olegario, Anthony; Powers, Paul

2002-06-01

This document represents work conducted as part of the Wind River Watershed Restoration Project during its second year of funding through the Bonneville Power Administration (BPA). The project is a comprehensive effort involving public and private entities seeking to restore water quality and fishery resources in the basin through cooperative actions. Project elements include coordination, watershed assessment, restoration, monitoring, and education. Entities involved with implementing project components are the Underwood Conservation District (UCD), USDA Forest Service (USFS), U.S. Geological Survey - Columbia River Research Lab (USGS-CRRL), and WA Department of Fish & Wildlife (WDFW).

TELECOM LAB

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IT-CS-TEL Section

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Balancing the risks: the NRU reactor and the isotope crisis in Canada

International Nuclear Information System (INIS)

Morrison, B.; Meneley, D.

2008-01-01

The extended shutdown of the NRU reactor at Chalk River at the end of 2007 caused a critical shortage of medical radioisotopes in Canada and the world, led to a unique meeting of Canada's Parliament to pass emergency legislation, and cost the President of the Canadian Nuclear Safety Commission her job. This paper, based on the public record, reviews these events from the perspective of the balance of risk between the safety of the NRU reactor and the impact of a shortage of isotopes. This leads to important questions about the mandate, independence and flexibility of the nuclear regulator, relations between the regulator, the government, and the licensee, and the government's overall management of risks. We argue that the government approaches individual risks in isolation and needs a mechanism to deal with multiple risks. (author)

Monitoring and assessment of radionuclide discharges from Temelín Nuclear Power Plant into the Vltava River (Czech Republic).