It's what's inside that counts: egg contaminant concentrations are influenced by estimates of egg density, egg volume, and fresh egg mass.

Science.gov (United States)

Herzog, Mark P; Ackerman, Joshua T; Eagles-Smith, Collin A; Hartman, C Alex

2016-05-01

In egg contaminant studies, it is necessary to calculate egg contaminant concentrations on a fresh wet weight basis and this requires accurate estimates of egg density and egg volume. We show that the inclusion or exclusion of the eggshell can influence egg contaminant concentrations, and we provide estimates of egg density (both with and without the eggshell) and egg-shape coefficients (used to estimate egg volume from egg morphometrics) for American avocet (Recurvirostra americana), black-necked stilt (Himantopus mexicanus), and Forster's tern (Sterna forsteri). Egg densities (g/cm(3)) estimated for whole eggs (1.056 ± 0.003) were higher than egg densities estimated for egg contents (1.024 ± 0.001), and were 1.059 ± 0.001 and 1.025 ± 0.001 for avocets, 1.056 ± 0.001 and 1.023 ± 0.001 for stilts, and 1.053 ± 0.002 and 1.025 ± 0.002 for terns. The egg-shape coefficients for egg volume (K v ) and egg mass (K w ) also differed depending on whether the eggshell was included (K v  = 0.491 ± 0.001; K w  = 0.518 ± 0.001) or excluded (K v  = 0.493 ± 0.001; K w  = 0.505 ± 0.001), and varied among species. Although egg contaminant concentrations are rarely meant to include the eggshell, we show that the typical inclusion of the eggshell in egg density and egg volume estimates results in egg contaminant concentrations being underestimated by 6-13 %. Our results demonstrate that the inclusion of the eggshell significantly influences estimates of egg density, egg volume, and fresh egg mass, which leads to egg contaminant concentrations that are biased low. We suggest that egg contaminant concentrations be calculated on a fresh wet weight basis using only internal egg-content densities, volumes, and masses appropriate for the species. For the three waterbirds in our study, these corrected coefficients are 1.024 ± 0.001 for egg density, 0.493 ± 0.001 for K v , and 0.505 ± 0.001 for K w .

Comparative evaluations of surface contamination detectors calibration with radioactive sources - used in the Goiania accident, and standard sources

International Nuclear Information System (INIS)

Becker, P.H.B.; Marecha, M.H.H.

1997-01-01

The construction of Cs-137 standard flat sources for calibration of surface contamination detectors, used in the Goiania accident in 1987, is described and the procedures adopted are reported. At that time, standard sources were not available. Nowadays the Instituto de Radioprotecao e Dosimetria has standard sources acquired from Amersham which are used as calibration standards for surface contamination detectors. Comparative evaluations between the standard flat sources constructed for the accident and the calibrated ones are presented

Method of making stepped photographic density standards of radiographic photographs

International Nuclear Information System (INIS)

Borovin, I.V.; Kondina, M.A.

1987-01-01

In industrial radiography practice the need often arises for a prompt evaluation of the photographic density of an x-ray film. A method of making stepped photographic density standards for industrial radiography by contact printing from a negative is described. The method is intended for industrial radiation flaw detection laboratories not having specialized sensitometric equipment

Levels of concern for radioactive contaminations in soil according to soil protection standards

International Nuclear Information System (INIS)

Gellermann, R.; Barkowski, D.; Machtolf, M.

2016-01-01

In the paper the question is examined whether the established soil protection standards for carcinogenic substances are also applicable to the assessment of radioactive soil contamination. Referring to the methods applied in soil protection for evaluation of dose-effectrelations and estimations of carcinogenic risks as well as the calculation methods for test values in soil protection ''levels of concern'' for soil contamination by artificial radionuclides are derived. The values obtained are significantly larger than the values for unrestricted clearance of ground according to the German Radiation Protection Ordinance (StrlSchV). The thesis that soil is protected according to environmental standards provided that radiation protection requirements are met needs further checks but can be probably confirmed if the radiation protection requirements are clearly defined.

Comparison of Breast Density Between Synthesized Versus Standard Digital Mammography.

Science.gov (United States)

Haider, Irfanullah; Morgan, Matthew; McGow, Anna; Stein, Matthew; Rezvani, Maryam; Freer, Phoebe; Hu, Nan; Fajardo, Laurie; Winkler, Nicole

2018-06-12

To evaluate perceptual difference in breast density classification using synthesized mammography (SM) compared with standard or full-field digital mammography (FFDM) for screening. This institutional review board-approved, retrospective, multireader study evaluated breast density on 200 patients who underwent baseline screening mammogram during which both SM and FFDM were obtained contemporaneously from June 1, 2016, through November 30, 2016. Qualitative breast density was independently assigned by seven readers initially evaluating FFDM alone. Then, in a separate session, these same readers assigned breast density using synthetic views alone on the same 200 patients. The readers were again blinded to each other's assignment. Qualitative density assessment was based on BI-RADS fifth edition. Interreader agreement was evaluated with κ statistic using 95% confidence intervals. Testing for homogeneity in paired proportions was performed using McNemar's test with a level of significance of .05. For patients across the SM and standard 2-D data set, diagnostic testing with McNemar's test with P = 0.32 demonstrates that the minimal density transitions across FFDM and SM are not statistically significant density shifts. Taking clinical significance into account, only 8 of 200 (4%) patients had clinically significant transition (dense versus not dense). There was substantial interreader agreement with overall κ in FFDM of 0.71 (minimum 0.53, maximum 0.81) and overall SM κ average of 0.63 (minimum 0.56, maximum 0.87). Overall subjective breast density assignment by radiologists on SM is similar to density assignment on standard 2-D mammogram. Copyright © 2018 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Permeability response of oil-contaminated compacted clays

International Nuclear Information System (INIS)

Silvestri, V.; Mikhail, N.; Soulie, M.

1997-01-01

This paper presents the results of a laboratory investigation on the behavior of motor oil-contaminated, partially saturated compacted clays. For the study, both a natural clay and an artificially purified kaolinite, contaminated with 0 to 8% of motor oil, were firstly compacted following the ASTM standard procedure. Secondly, permeability tests were carried out in a triaxial cell on 10 cm-diameter compacted clay specimens. The results of the investigation indicate that increasing percentages of motor oil decrease both the optimum water content and the optimum dry density of the two clays. However, whereas the optimum water content on the average decreases by about 6% when the percentage contamination increases from 0 to 8%, the corresponding decrease in the optimum dry density is less than 3%. Even though the optimum dry density decreases as the percentage of oil increases from 0 to 8%, there is, however, a range in oil content varying between 2 and 4% for which the optimum dry density is slightly greater than that of the untreated soils. As far as the permeability tests are concerned, the results indicate that as the percentage of oil increases, the coefficient of permeability decreases substantially, especially for clay specimens which were initially compacted on the dry side of optimum

The development of the American National Standard 'control of radioactive surface contamination on materials equipment and facilities to be released for uncontrolled use'

International Nuclear Information System (INIS)

Shapiro, J.

1980-01-01

A new standard submitted by the Health Physics Society Standards Committee to the American National Standards Institute concerning radioactive surface contamination of materials and equipment is discussed. The chronological events in the development of this standard are given. The standard provides criteria for the release for uncontrolled use of materials, equipment and facilities contaminated or potentially contaminated with radioactivity. Permissible contamination limits are specified for: 1) long lived alpha emitters except natural uranium and thorium, 2) more hazardous beta-gamma emitters, 3) less hazardous beta-gamma emitters and 4) natural uranium and thorium. A contamination reference level of 1000 dpm/100 cm 2 for 90 Sr was set as the basis for assigning limits to radionuclides presenting an ingestion hazard and other radionuclides were grouped based on the values of their maximum permissible concentration (MPC) in water relative to 90 Sr. The contamination limit for 239 Pu was chosen as the basis for assigning limits based on MPC in air to radionuclides presenting an inhalation hazard; a value of 100 dpm/100 cm 2 was adopted in the standard. An upper limit of 5000 dpm/100 cm 2 for surface contamination was selected for the standard. (UK)

[New container of sample: role in the reduction of bacterial contamination of standard platelet units].

Science.gov (United States)

Fehri, S; Tazi, I; Loukhmass, L; Benchemsi, N

2006-12-01

Bacterial contamination of unstable blood products constitutes today the most frequent infectious risk transmitted by blood transfusion. Platelet concentrates are often incrimineted. As responsible germs are in general of cutaneous origin, a sample procedure with diversion of the first 20 ml during blood donation is studied. The aim of this study is to evaluate the results of this technique on bacterial contamination rate of standard platelet units prepared at the regional blood transfusion center in Casablanca. A comparative study of two types of sample pockets is made: 500 Standard Platelet concentrates (CPS) are prepared after collection using standard triple bags (Baxter) (group 1) and 560 pockets of CPS were prepared after collection using triple bags with Sample Diversion Pouch sampling system for elimination of the first 20 ml of donation (Macopharma and Terumo) (group 2). The skin was disinfected in two times with alcohol 70%. The bacteriological study was made in the two groups at the third day of conservation. Six CPS of group 1 were contaminated, of which five were staphylococci coagulase negative and one bacillus sp. Six CPS of group 2 were contaminated, of which five were staphylococci coagulase negative and one staphylococcus aureus. The bacteria isolated were those of cutaneous flora at 100%. Diversion of first 20 ml of blood donation results in a 16.6% reduction in bacterial contamination of CPS (P>0.05). The non-significant reduction in the prevalence of the bacterial infection of CP formulates the problem of the indication of the sampling devices with derivation of first 20 ml during blood collection.

Association of leukemia with radium groundwater contamination

International Nuclear Information System (INIS)

Lyman, G.H.; Lyman, C.G.; Johnson, W.

1985-01-01

Radiation exposure, including the ingestion of radium, has been causally associated with leukemia in man. Groundwater samples from 27 counties on or near Florida phosphate lands were found to exceed 5 pCi/L total radium in 12.4% of measurements. The incidence of leukemia was greater in those counties with high levels of radium contamination (greater than 10% of the samples contaminated) than in those with low levels of contamination. Rank correlation coefficients of .56 and .45 were observed between the radium contamination level and the incidence of total leukemia and acute myeloid leukemia, respectively. The standardized incidence density ratio for those in high-contamination counties was 1.5 for total leukemia and 2.0 for acute myeloid leukemia. Further investigation is necessary, however, before a causal relationship between groundwater radium content and human leukemia can be established

Assessment of chromium biostabilization in contaminated soils using standard leaching and sequential extraction techniques

International Nuclear Information System (INIS)

Papassiopi, Nymphodora; Kontoyianni, Athina; Vaxevanidou, Katerina; Xenidis, Anthimos

2009-01-01

The iron reducing microorganism Desulfuromonas palmitatis was evaluated as potential biostabilization agent for the remediation of chromate contaminated soils. D. palmitatis were used for the treatment of soil samples artificially contaminated with Cr(VI) at two levels, i.e. 200 and 500 mg kg -1 . The efficiency of the treatment was evaluated by applying several standard extraction techniques on the soil samples before and after treatment, such as the EN12457 standard leaching test, the US EPA 3060A alkaline digestion method and the BCR sequential extraction procedure. The water soluble chromium as evaluated with the EN leaching test, was found to decrease after the biostabilization treatment from 13 to less than 0.5 mg kg -1 and from 120 to 5.6 mg kg -1 for the soil samples contaminated with 200 and 500 mg Cr(VI) per kg soil respectively. The BCR sequential extraction scheme, although not providing accurate estimates about the initial chromium speciation in contaminated soils, proved to be a useful tool for monitoring the relative changes in element partitioning, as a consequence of the stabilization treatment. After bioreduction, the percentage of chromium retained in the two least soluble BCR fractions, i.e. the 'oxidizable' and 'residual' fractions, increased from 54 and 73% to more than 96% in both soils

The development of the American national standard, ''control of radioactive surface contamination on materials, equipment and facilities to be released for uncontrolled use''

International Nuclear Information System (INIS)

Shapiro, J.

1980-01-01

The American National Standard, Control of Radioactive Surface Contamination on Materials, Equipment and Facilities to be Released for Uncontrolled Use, was developed under the procedures of ANSI for ANSI Main Committee N13 (Radiation Protection) by a working group of the Health Physics Society Standards Committee. This standard provides criteria for the control of materials, equipment and facilities contaminated with radioactivity proposed to be released for uncontrolled use. Permissible contamination limits are specified as well as methods assessing the levels of contamination. This paper reviews the proceedings of the Subcommittee on Radioactive Surface Contamination, the comments received by reviewers of the standard, the resolution of the committee, and the bases for reaching the final limits, recommendations, and measurement procedures. (H.K.)

Complete release from regulatory control via the density of radioactive contamination of soil of the Chornobyl exclusion zone

International Nuclear Information System (INIS)

Bondarenko, Oleg; Fadeev, Mykhaylo; Kireev, Serhiy; Proskura, Mykola

2008-01-01

Full text: In this work a general procedure of establishment the criterion of complete release from regulatory control via the density of radioactive contamination of soil of alone areas of the Chornobyl exclusion zone is represented by the following three stages, namely: 1) Justification of the dose criterion of complete release by applying the fundamental approaches of regulating the prolonged exposure of the public on a basement of ICRP Publication No. 82; 2) Justification of a procedure for establishment of dose constraint through evaluation of the statistical distribution of a controlled radiation value through determination of the high boundary of the confidence interval; 3) Generalization of conversion coefficients (via the density of radioactive contamination of soil) and coverage coefficients for the dose forming factors of the public (inhalation intake of transuranium radionuclides both at natural and technogenic dust resuspension, peroral intake of 137 Cs and 90 Sr via food stuff, external exposure from 137 Cs); on a basis of these coefficients average doses and dose constraint of a critical group of the public are calculated. As it is shown in the work, the generalized criterion of complete release from regulatory control via the density of radioactive contamination of soil of the Chornobyl exclusion zone can be defined by dividing the recommended ICRP dose clearance level for situation of the post-accidental prolonged exposure of a critical group of the public, namely, 0.3 mSv·year -1 to the dose conversion coefficient (i.e. transfer from the superficial soil contamination of radioactivity to the dose constraint for the Chornobyl exclusion zone), namely, 12.9 μSv·year -1 /((kBq·M -2 ). Thus, a level of the density of radioactive contamination of soil, that provides the complete release from regulatory control makes 23.3 kBq·M -2 . For completion of the work on justification of the criterion of complete territory release in the conditions of

Spin contamination analogy, Kramers pairs symmetry and spin density representations at the 2-component unrestricted Hartree-Fock level of theory

KAUST Repository

Bučinský, Lukáš

2015-05-11

"Kramers pairs symmetry breaking" is evaluated at the 2-component (2c) Kramers unrestricted and/or general complex Hartree-Fock (GCHF) level of theory, and its analogy with "spin contamination" at the 1-component (1c) unrestricted Hartree-Fock (UHF) level of theory is emphasized. The GCHF "Kramers pairs symmetry breaking" evaluation is using the square of overlaps between the set of occupied spinorbitals with the projected set of Kramers pairs. In the same fashion, overlaps between α and β orbitals are used in the evaluation of "spin contamination" at the UHF level of theory. In this manner, UHF Š2 expectation value is made formally extended to the GCHF case. The directly evaluated GCHF expectation value of the Š2 operator is considered for completeness. It is found that the 2c GCHF Kramers pairs symmetry breaking has a very similar extent in comparison to the 1c UHF spin contamination. Thus higher excited states contributions to the 1c and 2c unrestricted wave functions of open shell systems have almost the same extent and physical consequences. Moreover, it is formally shown that a single determinant wave function in the restricted open shell Kramers case has the expectation value of K2 operator equal to the negative number of open shell electrons, while the eigenvalue of K2 for the series of simple systems (H, He, He*-triplet, Li and Li*-quartet) are found to be equal to minus the square of the number of open shell electrons. The concept of unpaired electron density is extended to the GCHF regime and compared to UHF and restricted open shell Hartree-Fock spin density. The "collinear" and "noncollinear" analogs of spin density at the GCHF level of theory are considered as well. Spin contamination and/or Kramers pairs symmetry breaking, spin populations and spin densities are considered for H2O+, Cl, HCl+, phenoxyl radical (C6H5O) as well as for Cu, Cu2+, Fe and the [OsCl5(1H-pyrazole)]- anion. The 1c and 2c unpaired electron density representation is found

Standard Practice for Sampling for Particulate Contamination by Tape Lift

CERN Document Server

American Society for Testing and Materials. Philadelphia

2006-01-01

1.1 This practice covers procedures for sampling surfaces to determine the presence of particulate contamination, 5 m and larger. The practice consists of the application of a pressure-sensitive tape to the surface followed by the removal of particulate contamination with the removal of the tape. The tape with the adhering particles is then mounted on counting slides. Counting and measuring of particles is done by standard techniques. 1.2 This practice describes the materials and equipment required to perform sampling of surfaces for particle counting and sizing. 1.3 The criteria for acceptance or rejection of a part for conformance to surface cleanliness level requirements shall be determined by the user and are not included in this practice. 1.4 This practice is for use on surfaces that are not damaged by the application of adhesive tape. The use of this practice on any surface of any material not previously tested or for which the susceptibility to damage is unknown is not recommended. In general, metal...

Technique for fabrication of gradual standards of radiographic image blachening density

International Nuclear Information System (INIS)

Borovin, I.V.; Kondina, M.A.

1987-01-01

The technique of fabrication of gradual standards of blackening density for industrial radiography by contact printing from a negative is described. The technique is designed for possibilities of industrial laboratoriesof radiation defectoscopy possessing no special-purpose sensitometric equipment

Reference sources for the calibration of surface contamination monitors - Beta-emitters (maximum beta energy greater than MeV) and alpha-emitters (International Standard Publication ISO 8769:1988)

International Nuclear Information System (INIS)

Stefanik, J.

2001-01-01

This International Standard specifies the characteristics of reference sources of radioactive surface contamination, traceable to national measurement standards, for the calibration of surface contamination monitors. This International Standard relates to alpha-emitters and to beta-emitters of maximum beta energy greater than 0,15 MeV. It does not describe the procedures involved in the use of these reference sources for the calibration of surface contamination monitors. Such procedures are specified in IEC Publication 325 and other documents. This International Standard specifies reference radiations for the calibration of surface contamination monitors which take the form of adequately characterized large area sources specified, without exception, in terms of activity and surface emission rate, the evaluation of these quantities being traceable to national standards

[Development of a software standardizing optical density with operation settings related to several limitations].

Science.gov (United States)

Tu, Xiao-Ming; Zhang, Zuo-Heng; Wan, Cheng; Zheng, Yu; Xu, Jin-Mei; Zhang, Yuan-Yuan; Luo, Jian-Ping; Wu, Hai-Wei

2012-12-01

To develop a software that can be used to standardize optical density to normalize the procedures and results of standardization in order to effectively solve several problems generated during standardization of in-direct ELISA results. The software was designed based on the I-STOD method with operation settings to solve the problems that one might encounter during the standardization. Matlab GUI was used as a tool for the development. The software was tested with the results of the detection of sera of persons from schistosomiasis japonica endemic areas. I-STOD V1.0 (WINDOWS XP/WIN 7, 0.5 GB) was successfully developed to standardize optical density. A serial of serum samples from schistosomiasis japonica endemic areas were used to examine the operational effects of I-STOD V1.0 software. The results indicated that the software successfully overcame several problems including reliability of standard curve, applicable scope of samples and determination of dilution for samples outside the scope, so that I-STOD was performed more conveniently and the results of standardization were more consistent. I-STOD V1.0 is a professional software based on I-STOD. It can be easily operated and can effectively standardize the testing results of in-direct ELISA.

Densities of Barrow's goldeneyes during winter in Prince William Sound, Alaska in relation to habitat, food, and history of oil contamination

Science.gov (United States)

Esler, Daniel N.; Bowman, Timothy D.; O'Clair, Charles E.; Dean, Thomas A.; McDonald, Lyman L.

2000-01-01

We evaluated variation in densities of Barrow's Goldeneyes (Bucephala islandica) during winter at 214 sites within oiled and unoiled study areas in Prince William Sound, Alaska in relation to physical habitat attributes, prey biomass, and history of habitat contamination by the 1989 Exxon Valdez oil spill. Using general linear model analyses, we found that goldeneye densities were positively associated with occurrence of a stream within 200 m, lack of exposure to wind and waves, and mixed (versus rocky) substrate. We speculate that these associations relate to habitat profitability via selection of beneficial attributes and avoidance of detrimental features. We also determined that biomass of blue mussels (Mytilus trossulus), the primary prey, was not related to Barrow's Goldeneye densities; we suggest that mussel standing stock exceeds predation demands in our study areas and, thus, does not dictate goldeneye distribution. After accounting for habitat effects, we detected no effect of history of oil contamination on Barrow's Goldeneye densities, suggesting that populations have recovered from the oil spill. Although other studies documented hydrocarbon exposure in Barrow's Goldeneyes through at least 1997, either the level of exposure did not affect populations via reductions in survival, or effects of oil exposure were offset by immigration.

Adiabatic density perturbations and matter generation from the minimal supersymmetric standard model.

Science.gov (United States)

Enqvist, Kari; Kasuya, Shinta; Mazumdar, Anupam

2003-03-07

We propose that the inflaton is coupled to ordinary matter only gravitationally and that it decays into a completely hidden sector. In this scenario both baryonic and dark matter originate from the decay of a flat direction of the minimal supersymmetric standard model, which is shown to generate the desired adiabatic perturbation spectrum via the curvaton mechanism. The requirement that the energy density along the flat direction dominates over the inflaton decay products fixes the flat direction almost uniquely. The present residual energy density in the hidden sector is typically shown to be small.

Development of a low cost, GPS-based upgrade to a standard handheld gamma detector for mapping environmental radioactive contamination

International Nuclear Information System (INIS)

Paridaens, J.

2006-01-01

A low cost extension to a standard handheld radiation monitor was developed, allowing one to perform outdoor georeferenced gamma measurements. It consists of a commercial wireless Bluetooth[reg] GPS receiver, a commercial RS-232 to Bluetooth[reg] converter combined with a standard Bluetooth[reg] enabled pocket personal computer (PPC). The system is intended for use in difficult to access areas, typically for foot campaigns. As the operator walks, a straightforward homemade visual basic program alternately reads GPS position and gamma dose rate into the PPC, creating a data log. This allows a single operator on foot to map between 50 and 200 ha of environmental radiation per day in very rugged areas, depending on the accessibility of the terrain and the detail required. On a test field with known contamination, a spatial precision of about 5-10 m was obtainable. The device was also used to reveal complex contamination patterns in the flooding zones of a radioactively contaminated small river

Development of a low cost, GPS-based upgrade to a standard handheld gamma detector for mapping environmental radioactive contamination.

Science.gov (United States)

Paridaens, J

2006-02-01

A low cost extension to a standard handheld radiation monitor was developed, allowing one to perform outdoor georeferenced gamma measurements. It consists of a commercial wireless Bluetooth GPS receiver, a commercial RS-232 to Bluetooth converter combined with a standard Bluetooth enabled pocket personal computer (PPC). The system is intended for use in difficult to access areas, typically for foot campaigns. As the operator walks, a straightforward homemade visual basic program alternately reads GPS position and gamma dose rate into the PPC, creating a data log. This allows a single operator on foot to map between 50 and 200 ha of environmental radiation per day in very rugged areas, depending on the accessibility of the terrain and the detail required. On a test field with known contamination, a spatial precision of about 5-10 m was obtainable. The device was also used to reveal complex contamination patterns in the flooding zones of a radioactively contaminated small river.

Development of a low cost, GPS-based upgrade to a standard handheld gamma detector for mapping environmental radioactive contamination

Energy Technology Data Exchange (ETDEWEB)

Paridaens, J. [Belgian Nuclear Research Centre, SCK.CEN, Boeretang 200, B2400 Mol (Belgium)]. E-mail: jparidae@sckcen.be

2006-02-15

A low cost extension to a standard handheld radiation monitor was developed, allowing one to perform outdoor georeferenced gamma measurements. It consists of a commercial wireless Bluetooth[reg] GPS receiver, a commercial RS-232 to Bluetooth[reg] converter combined with a standard Bluetooth[reg] enabled pocket personal computer (PPC). The system is intended for use in difficult to access areas, typically for foot campaigns. As the operator walks, a straightforward homemade visual basic program alternately reads GPS position and gamma dose rate into the PPC, creating a data log. This allows a single operator on foot to map between 50 and 200 ha of environmental radiation per day in very rugged areas, depending on the accessibility of the terrain and the detail required. On a test field with known contamination, a spatial precision of about 5-10 m was obtainable. The device was also used to reveal complex contamination patterns in the flooding zones of a radioactively contaminated small river.

An analysis of the impact of native oxide, surface contamination and material density on total electron yield in the absence of surface charging effects

Energy Technology Data Exchange (ETDEWEB)

Iida, Susumu, E-mail: susumu.iida@toshiba.co.jp [EUVL Infrastructure Development Center, Inc., 16-1 Onogawa, Tsukuba-shi, Ibaraki-ken, 305-8569 (Japan); Ohya, Kaoru [Institute of Technology and Science, The University of Tokushima, 2-1 Minamijyousanjima-cho,Tokushima, 770-8506 (Japan); Hirano, Ryoichi; Watanabe, Hidehiro [EUVL Infrastructure Development Center, Inc., 16-1 Onogawa, Tsukuba-shi, Ibaraki-ken, 305-8569 (Japan)

2016-10-30

Highlights: • Total electron yields were assessed in the absence of any surface charging effect. • Experimental and simulation results showed a low native oxide energy barrier. • The yield enhancement effect of a native oxide layer was confirmed. • The yield enhancement effect of a thin surface contamination layer was confirmed. • Deviations in the material density from the theoretical values were evaluated. - Abstract: The effects of the presence of a native oxide film or surface contamination as well as variations in material density on the total electron yield (TEY) of Ru and B{sub 4}C were assessed in the absence of any surface charging effect. The experimental results were analyzed using semi-empirical Monte Carlo simulations and demonstrated that a native oxide film increased the TEY, and that this effect varied with film thickness. These phenomena were explained based on the effect of the backscattered electrons (BSEs) at the interface between Ru and RuO{sub 2}, as well as the lower potential barrier of RuO{sub 2}. Deviations in the material density from the theoretical values were attributed to the film deposition procedure based on fitting simulated TEY curves to experimental results. In the case of B{sub 4}C, the TEY was enhanced by the presence of a 0.8-nm-thick surface contamination film consisting of oxygenated hydrocarbons. The effect of the low potential barrier of the contamination film was found to be significant, as the density of the B{sub 4}C was much lower than that of the Ru. Comparing the simulation parameters generated in the present work with Joy’s database, it was found that the model and the input parameters used in the simulations were sufficiently accurate.

Influence of orthopedic reinforced gloves versus double standard gloves on contamination events during small animal orthopedic surgery.

Science.gov (United States)

Hayes, Galina; Singh, Ameet; Gibson, Tom; Moens, Noel; Oblak, Michelle; Ogilvie, Adam; Reynolds, Debbie

2017-10-01

To determine the influence of orthopedic reinforced gloves on contamination events during small animal orthopedic surgery. Prospective randomized controlled trial SAMPLE POPULATION: Two hundred and thirty-seven pairs of orthopedic gloves (474 gloves) and 203 pairs of double standard gloves (812 gloves) worn during 193 orthopedic procedures. Primary and assistant surgeons were randomized to wear either orthopedic reinforced gloves or double gloves. Gloves were leak tested to identify perforations at the end of procedures. Perforations detected intraoperatively or postoperatively were recorded. A contamination event was defined as at least one perforation on either hand for orthopedic reinforced gloves, or a perforation of both the inner and outer glove on the same hand for double gloves. Baseline characteristics between the 2 intervention groups were similar. There was no difference in contamination events between the double-gloved and orthopedic gloved groups (OR = 0.95, 95% CI = 0.49-1.87, P = .89). The same percentage of contamination events (8% glove pairs used) occurred in the double gloved group (17 contamination events) and in the orthopedic gloved group (19 contamination events). The odds of a contamination event increased by 1.02 (95% CI 1.01-1.03, P contamination events in small animal orthopedic procedures. Surgeons reluctant to double glove due to perceptions of decreased dexterity and discomfort may safely opt for wearing orthopedic gloves, which may improve their compliance. © 2017 The American College of Veterinary Surgeons.

Standard Practice for Preparation of Aerospace Contamination Control Plans

CERN Document Server

American Society for Testing and Materials. Philadelphia

2009-01-01

1.1 This practice is intended to assist in the preparation of formal plans for contamination control, especially of aerospace critical surfaces. Requirements may be established at the systems level, either by the customer or the systems integrator, or at the subsystem level. Subsystem requirements may be imposed by the responsible subsystem supplier or they may be flowed down from the systems organization (4.7). The extent of detail and level of cleanliness required can vary with the particular application and type of hardware being built, but all aspects of contamination control must be included in a final plan. Therefore, each of the following elements must be considered for inclusion in a contamination control plan (CCP): 1.1.1 Cleanliness requirements for deliverable hardware addressing particulate, molecular, or biological contaminants or combination thereof. Specify contamination limits and any budget allocations. 1.1.2 Implementation plans to achieve, verify, and maintain the specified cleanliness re...

Comparison of the surface contamination of class A shielded containment gloves and a standard shielded containment - professional practices evaluation radiopharmacy Public assistance Marseille hospitals; Comparaison de la contamination de surface des gants d'une enceinte blindee de classe A et d'une enceinte blindee Standard - EPP radiopharmacie APHM

Energy Technology Data Exchange (ETDEWEB)

Lopez, V.; Giraud, F.; Pisano, P.; Guillet, B. [CHU Nord, Marseille, Service de radiopharmacie, 13 (France); CHU Timone, service de radiopharmacie, 13 - Marseille (France)

2010-07-01

Purpose: The pole of Pharmacy of 'Assistance Publique des Hopitaux de Marseille' initiated a process of evaluation of professional practice. The two functional units of radiopharmacy are involved by comparing the surface contamination of gloves of a class A cell and a standard shielded cell, both in class D premises. Conclusions: In a shielded Class A cell placed in class D premises, there is microbial contamination of gloves probably due to the introduction of not disinfected equipment. In a standard shielded cell where contamination is most important, gloves cleaning should be performed several times during the workday, at least every four hours with a surface bactericidal and fungicidal agent. (N.C.)

Thermal Expansion and Density Data of UO2 and Simulated Fuel for Standard Reference

International Nuclear Information System (INIS)

Yang, Jae Hwan; Na, S. H.; Lee, J. W.; Kang, K. H.

2010-01-01

Standard Reference Data (SRD) is the scientific, technical data whose reliability and accuracy are evaluated by scientist group. Since SRD has a great impact on the improvement of national competitiveness by stirring up technological innovation in every sector of industries, many countries are making great efforts on establishing SRD in various areas. Data center for nuclear fuel material in Korea Atomic Energy Research Institute plays a role to providing property data of nuclear fuel material at high temperature, pressure, and radiation which are essential for the safety evaluation of nuclear power. In this study, standardization of data on thermal expansion and density of UO 2 were carried out in the temperature range from 300 K to 3100 K via uncertainty evaluation of indirectly produced data. Besides, standardization of data on thermal expansion and density of simulated fuel were also done in the temperature range from 350 K to 1750 K via uncertainty evaluation of directly produced data

Direct contamination - seasonality

International Nuclear Information System (INIS)

Aarkrog, A.

1994-01-01

Direct contamination is the primary pathway to terrestrial vegetation in the first period after an activity release to the atmosphere. All radionuclides are able to be transferred via this pathway. Deposition, interception and retention are the three processes involved in direct contamination of crops. Wet deposition is more important than dry deposition in temperature regions. Resuspension and rainsplash both belong to secondary direct deposition and became evident for e.g. radiocaesium after the Chernobyl accident. Seasonality is the varying response to radioactive contamination of crops according to the time of the year when the contamination occurs. Shortlived radionuclides (as 131 I) and those that mainly enter the foodchain by direct contamination (e.g. 137 Cs) are especially important in this connection. In particular, the contamination of cereal crops is influenced by seasonality. As a result of seasonality the impact of the Chernobyl accident on the radioactive contamination of human diet was for the same deposition density higher in southern than in northern Europe. (orig.)

Standards and guidelines pertinent to the development of decommissioning criteria for sites contaminated with radioactive material

International Nuclear Information System (INIS)

Dickson, H.W.

1978-08-01

A review of existing health and safety standards and guidelines has been undertaken to assist in the development of criteria for the decontamination and decommissioning of property contaminated with radioactive material. During the early years of development of the nuclear program in the United States, a number of sites were used which became contaminated with radioactive material. Many of these sites are no longer useful for nuclear activities, and the U.S. DOE desires to develop criteria for the management of these sites for future uses. Radiation protection standards promulgated by ICRP, NCRP, and ANSI have been considered. Government regulations, from the Code of Federal Regulations and the legal codes of various states, as well as regulatory guidelines with specific application to decommissioning of nuclear facilities also have been reviewed. In addition, recommendations of other scientific organizations such as the National Academy of Sciences/National Research Council Advisory Committee on the Biological Effects of Ionizing Radiations and the United Nations Scientific Committee on the Effects of Atomic Radiation were considered. Finally, a few specific recommendations and discussions from current literature were included. 28 references

Soil contamination standards for protection of personnel

International Nuclear Information System (INIS)

Rittmann, P.D.

1998-01-01

The objective of this report is to recommend soil contamination levels that will ensure that radionuclide intakes by unprotected workers are likely to give internal doses below selected dose limits during the working year. The three internal dose limits are 1, 100, and 500 mrem per year. In addition, photon, beta, and alpha instrument readings are estimated for these soil concentration limits. Two exposure pathways are considered: the first is inhalation of resuspended dust and the second is ingestion of trace amounts of soil. In addition, radioactive decay and ingrowth of progeny during the year of exposure is included. External dose from the soil contamination is not included because monitoring and control of external exposures is carried out independently from internal exposures, which are the focus of this report. The methods used are similar to those used by Carbaugh and Bihl (1993) to set bioassay criteria for such workers

Soil contamination standards for protection of personnel

Energy Technology Data Exchange (ETDEWEB)

Rittmann, P.D.

1998-04-16

The objective of this report is to recommend soil contamination levels that will ensure that radionuclide intakes by unprotected workers are likely to give internal doses below selected dose limits during the working year. The three internal dose limits are 1, 100, and 500 mrem per year. In addition, photon, beta, and alpha instrument readings are estimated for these soil concentration limits. Two exposure pathways are considered: the first is inhalation of resuspended dust and the second is ingestion of trace amounts of soil. In addition, radioactive decay and ingrowth of progeny during the year of exposure is included. External dose from the soil contamination is not included because monitoring and control of external exposures is carried out independently from internal exposures, which are the focus of this report. The methods used are similar to those used by Carbaugh and Bihl (1993) to set bioassay criteria for such workers.

Determination of silicone rubber and low-density polyethylene diffusion and polymer/water partition coefficients for emerging contaminants.

Science.gov (United States)

Pintado-Herrera, Marina G; Lara-Martín, Pablo A; González-Mazo, Eduardo; Allan, Ian J

2016-09-01

There is a growing interest in assessing the concentration and distribution of new nonregulated organic compounds (emerging contaminants) in the environment. The measurement of freely dissolved concentrations using conventional approaches is challenging because of the low concentrations that may be encountered and their temporally variable emissions. Absorption-based passive sampling enables the estimation of freely dissolved concentrations of hydrophobic contaminants of emerging concern in water. In the present study, calibration was undertaken for 2 polymers, low-density polyethylene (LDPE) and silicone rubber for 11 fragrances, 5 endocrine-disrupting compounds, 7 ultraviolet (UV) filters, and 8 organophosphate flame retardant compounds. Batch experiments were performed to estimate contaminant diffusion coefficients in the polymers (Dp ), which in general decreased with increasing molecular weight. The values for fragrances, endocrine-disrupting compounds, and UV filters were in ranges similar to those previously reported for polycyclic aromatic hydrocarbons, but were 1 order of magnitude lower for organophosphate flame retardant compounds. Silicone rubber had higher Dp values than LDPE and was therefore selected for further experiments to calculate polymer/water partition coefficients (KPW ). The authors observed a positive correlation between log KPW and log octanol/water partition coefficient values. Field testing of silicone rubber passive samplers was undertaken though exposure in the River Alna (Norway) for an exposure time of 21 d to estimate freely dissolved concentration. Some fragrances and UV filters were predominant over other emerging and regulated contaminants, at levels up to 1600 ng L(-1) for galaxolide and 448 ng L(-1) for octocrylene. Environ Toxicol Chem 2016;35:2162-2172. © 2016 SETAC. © 2016 SETAC.

Comparison of PCR with Standard Method (MPN for detection of bacterial contamination in drinking water

Directory of Open Access Journals (Sweden)

Fatemeh Dehghan

2014-11-01

Full Text Available Background: Detection of bacterial contamination in drinking water by culture method is a time and cost consuming method and spends a few days depending on contamination degree. However, the people use the tap water during that time. Molecular methods are rapid and sensitive. In this study a rapid Multiplex PCR method was used for rapid analysis both coliform bacteria and E.coli, and probable detection of VBNC bacteria in drinking water, the experiments were performed in bacteriological lab of water and Wastewater Corporation in Markazi province. Material and Methods:Amplification of a fragment from each of lacZ and uidA genes in a Multiplex PCR was used for detection of coliforms. Eight samples was taken from Arak drinking water system including 36 samples of wells, 41 samples of water distribution network and 3 samples from water storages were examined by amplification of lacZ and uidA genes in a Multiplex PCR. Equivalently, the MPN test was applied as a standard method for all samples for comparison of results. Standard bacteria, pure bacteria isolated from positive MPN and CRM were examined by PCR and MPN method. Results: The result of most samples water network, water storages, and water well were same in both MPN and PCR method .The results of standard bacteria and pure cultures of bacteria isolated from positive MPN and CRM confirmed the PCR method. Five samples were positive in PCR but negative in MPN method. Duration time of PCR was decreased about 105 min by changing the PCR program and electrophoreses factors. Conclusion: The Multiplex PCR can detect coliform bacteria and E.coli synchronous in drinking water.

Biological processes influencing contaminant release from sediments

International Nuclear Information System (INIS)

Reible, D.D.

1996-01-01

The influence of biological processes, including bioturbation, on the mobility of contaminants in freshwater sediments is described. Effective mass coefficients are estimated for tubificid oligochaetes as a function of worm behavior and biomass density. The mass transfer coefficients were observed to be inversely proportional to water oxygen content and proportional to the square root of biomass density. The sediment reworking and contaminant release are contrasted with those of freshwater amphipods. The implications of these and other biological processes for contaminant release and i n-situ remediation of soils and sediments are summarized. 4 figs., 1 tab

9 CFR 113.28 - Detection of mycoplasma contamination.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of mycoplasma contamination... REQUIREMENTS Standard Procedures § 113.28 Detection of mycoplasma contamination. The heart infusion test, using... for mycoplasma contamination is prescribed in an applicable Standard Requirement or in the filed...

Solid phase speciation of arsenic by sequential extraction in standard reference materials and industrially contaminated soil samples

International Nuclear Information System (INIS)

Herreweghe, Samuel van; Swennen, Rudy; Vandecasteele, Carlo; Cappuyns, Valerie

2003-01-01

Leaching experiments, a mineralogical survey and larger samples are preferred when arsenic is present as discrete mineral phases. - Availability, mobility, (phyto)toxicity and potential risk of contaminants is strongly affected by the manner of appearance of elements, the so-called speciation. Operational fractionation methods like sequential extractions have been applied for a long time to determine the solid phase speciation of heavy metals since direct determination of specific chemical compounds can not always be easily achieved. The three-step sequential extraction scheme recommended by the BCR and two extraction schemes based on the phosphorus-like protocol proposed by Manful (1992, Occurrence and Ecochemical Behaviours of Arsenic in a Goldsmelter Impacted Area in Ghana, PhD dissertation, at the RUG) were applied to four standard reference materials (SRM) and to a batch of samples from industrially contaminated sites, heavily contaminated with arsenic and heavy metals. The SRM 2710 (Montana soil) was found to be the most useful reference material for metal (Mn, Cu, Zn, As, Cd and Pb) fractionation using the BCR sequential extraction procedure. Two sequential extraction schemes were developed and compared for arsenic with the aim to establish a better fractionation and recovery rate than the BCR-scheme for this element in the SRM samples. The major part of arsenic was released from the heavily contaminated samples after NaOH-extraction. Inferior extraction variability and recovery in the heavily contaminated samples compared to SRMs could be mainly contributed to subsample heterogeneity

Spatial and Temporal Characteristics of Insulator Contaminations Revealed by Daily Observations of Equivalent Salt Deposit Density

Directory of Open Access Journals (Sweden)

Ling Ruan

2015-01-01

Full Text Available The accurate estimation of deposits adhering on insulators is of great significance to prevent pollution flashovers which cause huge costs worldwide. Researchers have developed sensors using different technologies to monitor insulator contamination on a fine time scale. However, there is lack of analysis of these data to reveal spatial and temporal characteristics of insulator contamination, and as a result the scheduling of periodical maintenance of power facilities is highly dependent on personal experience. Owing to the deployment of novel sensors, daily Equivalent Salt Deposit Density (ESDD observations of over two years were collected and analyzed for the first time. Results from 16 sites distributed in four regions of Hubei demonstrated that spatial heterogeneity can be seen at both the fine and coarse geographical scales, suggesting that current polluted area maps are necessary but are not sufficient conditions to guide the maintenance of power facilities. Both the local emission and the regional air pollution condition exert evident influences on deposit accumulation. A relationship between ESDD and PM10 was revealed by using regression analysis, proving that air pollution exerts influence on pollution accumulations on insulators. Moreover, the seasonality of ESDD was discovered for the first time by means of time series analysis, which could help engineers select appropriate times to clean the contamination. Besides, the trend component shows that the ESDD increases in a negative exponential fashion with the accumulation date (ESDD = a − b × exp(−time at a long time scale in real environments.

Relations between sinkhole density and anthropogenic contaminants in selected carbonate aquifers in the eastern United States

Science.gov (United States)

Lindsey, Bruce D.; Katz, Brian G.; Berndt, Marian P.; Ardis, Ann F.; Skach, Kenneth A.

2009-01-01

-use groups, particularly for agricultural land-use areas where pesticide use would be expected to be higher and more uniform areally compared to urban and forested areas. Although areas with agricultural land use and a high sinkhole density were most vulnerable (median nitrate-N concentration was 3.7 mg/L, 11% of samples exceeded 10 mg/L, and had the highest frequencies of pesticide detection), areas with agricultural land use and low sinkhole density still were vulnerable to contamination (median nitrate-N concentration was 1.5 mg/L, 8% of samples exceeded 10 mg/L, and had some of the highest frequencies of detections of pesticides). This may be due in part to incomplete or missing data regarding karst features (such as buried sinkholes, low-permeability material in bottom of sinkholes) that do not show up at the scales used for regional mapping and to inconsistent methods among states in karst feature delineation.

SU-E-I-59: Investigation of the Usefulness of a Standard Deviation and Mammary Gland Density as Indexes for Mammogram Classification.

Science.gov (United States)

Takarabe, S; Yabuuchi, H; Morishita, J

2012-06-01

To investigate the usefulness of the standard deviation of pixel values in a whole mammary glands region and the percentage of a high- density mammary glands region to a whole mammary glands region as features for classification of mammograms into four categories based on the ACR BI-RADS breast composition. We used 36 digital mediolateral oblique view mammograms (18 patients) approved by our IRB. These images were classified into the four categories of breast compositions by an experienced breast radiologist and the results of the classification were regarded as a gold standard. First, a whole mammary region in a breast was divided into two regions such as a high-density mammary glands region and a low/iso-density mammary glands region by using a threshold value that was obtained from the pixel values corresponding to a pectoral muscle region. Then the percentage of a high-density mammary glands region to a whole mammary glands region was calculated. In addition, as a new method, the standard deviation of pixel values in a whole mammary glands region was calculated as an index based on the intermingling of mammary glands and fats. Finally, all mammograms were classified by using the combination of the percentage of a high-density mammary glands region and the standard deviation of each image. The agreement rates of the classification between our proposed method and gold standard was 86% (31/36). This result signified that our method has the potential to classify mammograms. The combination of the standard deviation of pixel values in a whole mammary glands region and the percentage of a high-density mammary glands region to a whole mammary glands region was available as features to classify mammograms based on the ACR BI- RADS breast composition. © 2012 American Association of Physicists in Medicine.

Levels of concern for radioactive contaminations in soil according to soil protection standards; Besorgniswerte fuer Radionuklide in Boeden nach bodenschutzrechtlichen Massstaeben

Energy Technology Data Exchange (ETDEWEB)

Gellermann, R. [Nuclear Control and Consulting GmbH, Braunschweig (Germany); Barkowski, D.; Machtolf, M. [IFUA-Projekt-GmbH Bielefeld (Germany)

2016-07-01

In the paper the question is examined whether the established soil protection standards for carcinogenic substances are also applicable to the assessment of radioactive soil contamination. Referring to the methods applied in soil protection for evaluation of dose-effectrelations and estimations of carcinogenic risks as well as the calculation methods for test values in soil protection ''levels of concern'' for soil contamination by artificial radionuclides are derived. The values obtained are significantly larger than the values for unrestricted clearance of ground according to the German Radiation Protection Ordinance (StrlSchV). The thesis that soil is protected according to environmental standards provided that radiation protection requirements are met needs further checks but can be probably confirmed if the radiation protection requirements are clearly defined.

Dispersion of Contaminants in Indoor Climate

DEFF Research Database (Denmark)

Heiselberg, Per

In rooms ventilated by mixing ventilation, in order to remove contaminants from the occupied zone, the goal of the air distribution system is to achieve a low and even concentration distribution in the room. The experiments showed that the contaminant distribution in a room always will depend...... on the location of the contamination source and in practice also on the supplied air flow rate and the contaminant density. The results showed that it is important for the removal of contaminants in a room that the ventilation system is working in the same direction as the existing buoyancy forces....

Standard Test Method for Sizing and Counting Particulate Contaminant In and On Clean Room Garments

CERN Document Server

American Society for Testing and Materials. Philadelphia

2000-01-01

1.1 This test method covers the determination of detachable particulate contaminant 5 m or larger, in and on the fabric of clean room garments. 1.2 This test method does not apply to nonporous fabrics such as Tyvek or Gortex. It only applies to fabrics that are porous such as cotton or polyester. 1.3 The values stated in SI units are to be regarded as the standard. The inch-pound values given in parentheses are for information only. 1.4 This test method provides not only the traditional optical microscopic analysis but also a size distribution and surface obscuration analysis for particles on a fine-textured membrane filter or in a tape lift sample. It utilizes transmitted illumination to render all particles darker than the background for gray level detection. Particles collected on opaque plates must be transferred to a suitable membrane filter. This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associat...

Plutonium-contaminated fragments at the Taranaki site at Maralinga

International Nuclear Information System (INIS)

Burns, P.A.; Cooper, M.B.; Duggleby, J.C.; Mika, J.F.; Williams, G.A.

1986-07-01

A detailed assessment is presented of the distribution of plutonium-contaminated fragments and sub-millimetre particles in the vicinity of the Taranaki site at the former U.K. Atomic Weapons Test Range at Maralinga in South Australia. The area which is contaminated with fragments has been divided into three general regions with the designations 'heavily contaminated', 'moderately contaminated' and 'plumes'. The average surface density, activity and estimated total number of fragments are presented for each region. Average surface densities of all fragments with americium-241 activities greater than 2 kBq are estimated to be 33, 7 and 2 m -2 for the 'heavily contaminated', 'moderately contaminated' and 'plumes' regions respectively. The total number of such fragments is estimated to be in excess of three million which accounts for a total plutonium activity of approximately 0.8 TBq. The implications of these results for a rehabilitation program are discussed

Modelling of contamination of surface atmosphere for deflation of Cesium-137 on contaminated territories

International Nuclear Information System (INIS)

Bogdanov, A.P.; Zhmura, G.M.

1994-01-01

Presence of Cesium 137 in near land air is caused at the contaminated territories by 'local' dusting and transport of the dust from the zone of strong contamination. For large distance is it caused by resuspension of radioactive dust from the surface in the given region. In accordance with the models of dusting round square sources based on Gauss statistical model of dissemination of admixtures in the atmosphere, the contaminated areas of european part of the former of USSR with the density of contamination over 1 Ci/km 2 with Cesium 137 were represented by 30 round square sources covering the main spots of contamination. The results of calculation of contamination of the atmosphere for several cities of Belarus, Russia and Ukraine, where there are the permanent points of observation for the content of radionuclides in the air, have shown that the proposed model of dusting sources describes the contamination of near land air with Cesium 137 reasonably well. 7 refs., 3 tabs

MODELING THE ANOMALY OF SURFACE NUMBER DENSITIES OF GALAXIES ON THE GALACTIC EXTINCTION MAP DUE TO THEIR FIR EMISSION CONTAMINATION

Energy Technology Data Exchange (ETDEWEB)

Kashiwagi, Toshiya; Suto, Yasushi; Taruya, Atsushi; Yahata, Kazuhiro [Department of Physics, The University of Tokyo, Tokyo 113-0033 (Japan); Kayo, Issha [Department of Physics, Toho University, Funabashi, Chiba 274-8510 (Japan); Nishimichi, Takahiro, E-mail: kashiwagi@utap.phys.s.u-tokyo.ac.jp [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8568 (Japan)

2015-02-01

The most widely used Galactic extinction map is constructed assuming that the observed far-infrared (FIR) fluxes come entirely from Galactic dust. According to the earlier suggestion by Yahata et al., we consider how FIR emission of galaxies affects the SFD map. We first compute the surface number density of Sloan Digital Sky Survey (SDSS) DR7 galaxies as a function of the r-band extinction, A {sub r,} {sub SFD}. We confirm that the surface densities of those galaxies positively correlate with A {sub r,} {sub SFD} for A {sub r,} {sub SFD} < 0.1, as first discovered by Yahata et al. for SDSS DR4 galaxies. Next we construct an analytical model to compute the surface density of galaxies, taking into account the contamination of their FIR emission. We adopt a log-normal probability distribution for the ratio of 100 μm and r-band luminosities of each galaxy, y ≡ (νL){sub 100} {sub μm}/(νL) {sub r}. Then we search for the mean and rms values of y that fit the observed anomaly, using the analytical model. The required values to reproduce the anomaly are roughly consistent with those measured from the stacking analysis of SDSS galaxies. Due to the limitation of our statistical modeling, we are not yet able to remove the FIR contamination of galaxies from the extinction map. Nevertheless, the agreement with the model prediction suggests that the FIR emission of galaxies is mainly responsible for the observed anomaly. Whereas the corresponding systematic error in the Galactic extinction map is 0.1-1 mmag, it is directly correlated with galaxy clustering and thus needs to be carefully examined in precision cosmology.

Prevention of airborne contamination and cross-contamination in germ-free mice by laminar flow

NARCIS (Netherlands)

Waaij, D. van der; Andres, A.H.

1971-01-01

The efficacy of horizontal and vertical laminar flow units (equipped with high-efficiency air filters) in the prevention of cross-contamination between cages and of contamination from outside has been demonstrated. With germ-free mice and using germ-free standard techniques for sterilization and for

Geotechnical properties of oil-contaminated Kuwaiti sand

Energy Technology Data Exchange (ETDEWEB)

Al-Sanad, H.A.; Eid, W.K.; Ismael, N.F. [Kuwait Univ., Safat (Kuwait). Dept. of Civil Engineering

1995-05-01

Large quantities of oil-contaminated sands resulted from exploded oil wells, burning oil fires, the destruction of oil storage tanks, and the formation of oil lakes in Kuwait at the end of the Gulf War. An extensive laboratory testing program was carried out to determine the geotechnical characteristics of this material. Testing included basic properties, compaction and permeability tests, and triaxial and consolidation tests on clean and contaminated sand at the same relative density. Contaminated specimens were prepared by mixing the sand with oil in the amount of 6% by weight or less to match field conditions. The influence of the type of oil, and relative density was also investigated by direct shear tests. The results indicated a small reduction in strength and permeability and an increase in compressibility due to contamination. The preferred method of disposal of this material is to use it as a stabilizing material for other projects such as road construction.

Geotechnical properties of oil-contaminated Kuwaiti sand

International Nuclear Information System (INIS)

Al-Sanad, H.A.; Eid, W.K.; Ismael, N.F.

1995-01-01

Large quantities of oil-contaminated sands resulted from exploded oil wells, burning oil fires, the destruction of oil storage tanks, and the formation of oil lakes in Kuwait at the end of the Gulf War. An extensive laboratory testing program was carried out to determine the geotechnical characteristics of this material. Testing included basic properties, compaction and permeability tests, and triaxial and consolidation tests on clean and contaminated sand at the same relative density. Contaminated specimens were prepared by mixing the sand with oil in the amount of 6% by weight or less to match field conditions. The influence of the type of oil, and relative density was also investigated by direct shear tests. The results indicated a small reduction in strength and permeability and an increase in compressibility due to contamination. The preferred method of disposal of this material is to use it as a stabilizing material for other projects such as road construction

Standard Test Method for Water Absorption, Bulk Density, Apparent Porosity, and Apparent Specific Gravity of Fired Whiteware Products

CERN Document Server

American Society for Testing and Materials. Philadelphia

2006-01-01

1.1 This test method covers procedures for determining water absorption, bulk density, apparent porosity, and apparent specific gravity of fired unglazed whiteware products. 1.2 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Measurement of Radioactive Contamination on Work Clothing of Workers Engaged in Decontamination Operations

Science.gov (United States)

Tsujimura, Norio; Yoshida, Tadayoshi; Hoshi, Katsuya

To rationally judge the necessity of the contamination screening measurements required in the decontamination work regulations, a field study of the surface contamination density on the clothing of the workers engaged in decontamination operations was performed. The clothing and footwear of 20 workers was analyzed by high-purity germanium (HPGe) gamma-ray spectroscopy. The maximum radiocesium activities (134Cs + 137Cs) observed were 3600, 1300, and 2100 Bq for the work clothing, gloves, and boots, respectively, and the derived surface contamination densities were below the regulatory limit of 40 Bq/cm2. The results of this field study suggest that the upper bounds of the surface contamination density on the work clothing, gloves, and boots are predictable from the maximum soil loading density on the surface of clothing and footwear and the radioactivity concentration in soil at the site.

[Effect of low-dose or standard-dose conjugated equine estrogen combined with different progesterone on bone density in menopause syndrome women].

Science.gov (United States)

Zuo, H L; Deng, Y; Wang, Y F; Gao, L L; Xue, W; Zhu, S Y; Ma, X; Sun, A J

2018-04-25

Objective: To explore the effect of low-dose or standard-dose conjugated equine estrogen (CEE) combined with natural progesterone or dydrogesterone on bone density in menopause syndrome women. Methods: Totally 123 patients with menopause syndrome were recruited and randomly assigned to 3 treatment groups: group A (low-dose CEE+progesterone) , group B (standard-dose CEE+progesterone) , group C (standard-dose CEE+dydrogesterone) . Using continuous sequential regimen, the duration of intervention was 12 cycles. The bone mineral density of lumbar 2-4 and neck of femur, the bone metabolic markers, the level of FSH and estradiol were examined just before the drug administration and 12 months after the beginning of experiment. Results: There were 107 cases completed the one year trial. (1) Bone density: after 12 cycles of treatment, there was no significant change in bone density in group A ( P> 0.05) ; lumbar vertebrae of group B and C increased significantly, at 3.0% and 2.1%respectively (all Pdensity of left femoral neck of group C significantly increased by 2.9% ( P= 0.029) . There was no significant difference among the treatment groups at the beginning of experiment ( P> 0.05) . (2) Bone metabolic markers: after 12 cycles of treatment, the levels of calcium, phosphorus, alkaline phosphatase, Ca/Cr decreased significantly, the difference were statistically significant (all P 0.05) . (3) Levels of FSH and estradiol: after 12 cycles of treatment, the levels of FSH in three groups were decreased significantly (all P 0.05) . Conclusions: Both low-dose and standard-dose menopause hormone therapy (MHT) could elevate the level of estradiol, reduce bone turnover, prevent bone loss of postmenopausal women effectively. The standard dose of MHT could also increase the density of vertebrae and femoral neck, and generate more clinical benefits.

Development of the automatic measuring system to survey the surface contamination on equipments

International Nuclear Information System (INIS)

Ishizuka, Akira; Matsumura, Hidekatsu; Nawa, Takao; Yamaguchi, Seiji; Yamada, Tadashi.

1980-01-01

The inspection of surface contamination carried out when things are taken out of the control areas in nuclear power stations requires considerable labor and time because it is carried out manually. In order to make the inspection of surface contamination more efficiently and to standardize it, the development of an automatic inspection apparatus was carried out. This apparatus inspects the surface contamination due to radio isotopes which do not emit α-ray, and the objects to be measured are the large things with definite forms, such as boards and pipes for scaffolding. The method of measuring β-ray with a gas flow counter was adopted for the apparatus in view of the good detection sensitivity, relatively simple shielding against background, and easy conversion to surface contamination density. The measuring system was composed of the gas flow counters and a rate meter. The outline of the apparatus made for trial is explained. As the result of the performance test, the lowest detection sensitivity was 1.29 x 10 -5 μCi/cm 2 at the moving speed of an object of 1 cm/sec. The detection sensitivity is improved by the flattening of the sensitivity distribution. The evaluation of the error, the reduction of measuring time and the prevention of contamination were also made. (Kako, I.)

FOREWORD: Special issue on density

Science.gov (United States)

Fujii, Kenichi

2004-04-01

This special issue on density was undertaken to provide readers with an overview of the present state of the density standards for solids, liquids and gases, as well as the technologies developed for measuring density. This issue also includes topics on the refractive index of gases and on techniques used for calibrating hydrometers so that almost all areas concerned with density standards are covered in four review articles and seven original articles, most of which describe current research being conducted at national metrology institutes (NMIs). A review article was invited from the Ruhr-Universität Bochum to highlight research on the magnetic suspension densimeters. In metrology, the determinations of the volume of a weight and the density of air are of primary importance in establishing a mass standard because the effect of the buoyancy force of air acting on the weight must be known accurately to determine the mass of the weight. A density standard has therefore been developed at many NMIs with a close relation to the mass standard. Hydrostatic weighing is widely used to measure the volume of a solid. The most conventional hydrostatic weighing method uses water as a primary density standard for measuring the volume of a solid. A brief history of the determination of the density of water is therefore given in a review article, as well as a recommended value for the density of water with a specified isotopic abundance. The most modern technique for hydrostatic weighing uses a solid density standard instead of water. For this purpose, optical interferometers for measuring the diameters of silicon spheres have been developed to convert the length standard into the volume standard with a small uncertainty. A review article is therefore dedicated to describing the state-of-the-art optical interferometers developed for silicon spheres. Relative combined standard uncertainties of several parts in 108 have been achieved today for measuring the volume and density of

A new improved protocol for in vitro intratubular dentinal bacterial contamination for antimicrobial endodontic tests: standardization and validation by confocal laser scanning microscopy

Directory of Open Access Journals (Sweden)

Flaviana Bombarda de ANDRADE

2015-01-01

Full Text Available Objectives To compare three methods of intratubular contamination that simulate endodontic infections using confocal laser scanning microscopy (CLSM. Material and Methods Two pre-existing models of dentinal contamination were used to induce intratubular infection (groups A and B. These methods were modified in an attempt to improve the model (group C. Among the modifications it may be included: specimen contamination for five days, ultrasonic bath with BHI broth after specimen sterilization, use of E. faecalis during the exponential growth phase, greater concentration of inoculum, and two cycles of centrifugation on alternate days with changes of culture media. All specimens were longitudinally sectioned and stained with of LIVE/DEAD® for 20 min. Specimens were assessed using CLSM, which provided images of the depth of viable bacterial proliferation inside the dentinal tubules. Additionally, three examiners used scores to classify the CLSM images according to the following parameters: homogeneity, density, and depth of the bacterial contamination inside the dentinal tubules. Kruskal-Wallis and Dunn’s tests were used to evaluate the live and dead cells rates, and the scores obtained. Results The contamination scores revealed higher contamination levels in group C when compared with groups A and B (p0.05. The volume of live cells in group C was higher than in groups A and B (p<0.05. Conclusion The new protocol for intratubular infection resulted in high and uniform patterns of bacterial contamination and higher cell viability in all specimens when compared with the current methods.

Measurement of radioactive contamination on work clothing of workers engaged in decontamination operations

International Nuclear Information System (INIS)

Tsujimura, Norio; Yoshida, Tadayoshi; Hoshi, Katsuya

2016-01-01

To rationally judge the necessity of the contamination screening measurements required in the decontamination work regulations, a field study of the surface contamination density on the clothing of the workers engaged in decontamination operations was performed. The clothing and footwear of 20 workers was analyzed by high-purity germanium (HPGe) gamma-ray spectroscopy. The maximum radiocesium activities ("1"3"4Cs + "1"3"7Cs) observed were 3600, 1300, and 2100 Bq for the work clothing, gloves, and boots, respectively, and the derived surface contamination densities were below the regulatory limit of 40 Bq/cm"2. The results of this field study suggest that the upper bounds of the surface contamination density on the work clothing, gloves, and boots are predictable from the maximum soil loading density on the surface of clothing and footwear and the radioactivity concentration in soil at the site. (author)

Relating groundwater and sediment chemistry to microbial characterization at a BTEX-contaminated site

International Nuclear Information System (INIS)

Pfiffner, S.M.; Palumbo, A.V.; McCarthy, J.F.; Gibson, T.

1996-01-01

The National Center for Manufacturing Science is investigating bioremediation of petroleum hydrocarbon at a site in Belleville, Michigan. As part of this study we examined the microbial communities to help elucidate biodegradative processes currently active at the site. We observed high densities of aerobic hydrocarbon degraders and denitrifiers in the less-contaminated sediments. Low densities of iron and sulfate reducers were measured in the same sediments. In contrast, the highly-contaminated sediments showed low densities of aerobic hydrocarbon degraders and denitrifiers and high densities of iron and sulfate reducers. Methanogens were also found in these highly-contaminated sediments. These contaminated sediments also showed a higher biomass, by phospholipid fatty acids, and greater ratios of phospholipid fatty acids which indicate stress within the microbial community. Aquifer chemistry analyses indicated that the more-contaminated area was more reduced and had lower sulfate than the less-contaminated area. These conditions suggest that the subsurface environment at the highly-contaminated area had progressed into sulfate reduction and methanogensis. The less-contaminated area, although less reduced, also appeared to be progressing into primarily iron- and sulfate-reducing microbial communities. The proposed treatment to stimulate bioremediation includes addition of oxygen and nitrate. Groundwater chemistry and microbial analyses revealed significant differences resulted from the injection of dissolved oxygen and nitrate in the subsurface. These differences included increases in pH and Eh and large decreases in BTEX, dissolved iron, and sulfate concentrations at the injection well

Treatment of contaminated waste plastics material

International Nuclear Information System (INIS)

Sims, J.; Hitchcock, J.W.

1984-01-01

Radioactive contaminated plastics material is treated by reducing it to uniform-sized debris and extruding it from a heated extruder into a sealed container in monolithic block form or as an in-fill matrix for other contaminated waste articles to create a substantially void-free sealed mass for disposal. Density adjusting fillers may be included. Extrusion may alternatively take place into a clean sealable plastics tube. (author)

Density of liquid Ti-6Al-4V

Directory of Open Access Journals (Sweden)

Schmon Alexander

2017-01-01

Full Text Available Ti-6Al-4V is due to its high strength-density ratio a commonly used alloy in aerospace industry applications. But liquid phase data are scarce as preventing contaminations of the reactive high temperature melt during the investigation process poses a challenge. The thermophysical quantity density is of special interest since it is necessary input parameter in modern numerical casting and solidification simulations. Liquid phase density of Ti-6Al-4V as function of temperature was determined employing a fast resistive pulse-heating technique based on the approach to avoid contaminations of the specimen by extremely reducing the experimental duration of the investigation process. Temperature dependent density of liquid Ti-6Al-4V was determined in a temperature range between 2050 K and 2590 K and is presented.

Decontamination of radioactively contaminated surfaces - Method for testing and assessing the ease of decontamination (International Standard Publication ISO 8690:1988)

International Nuclear Information System (INIS)

Stefanik, J.

2001-01-01

The specifications laid down in this International Standard apply to the testing of surfaces which may become contaminated by radioactive materials. Decontaminability data obtained using this test method are not applicable to technical systems where layers of contaminating materials are formed as a result of long-term application of higher temperatures and pressures (for example primary circuits of nuclear reactors). The purpose of the test is to assess the ease of decontamination of surfaces under laboratory conditions. In practical applications, it may be important to consider other qualities, such as chemical, mechanical and radiation resistance and long-term stability in the selection of the materials to be used. It should be recognized that further decontamination tests under simulated service conditions may be needed

Microbial environmental contamination in Italian dental clinics: A multicenter study yielding recommendations for standardized sampling methods and threshold values.

Science.gov (United States)

Pasquarella, Cesira; Veronesi, Licia; Napoli, Christian; Castiglia, Paolo; Liguori, Giorgio; Rizzetto, Rolando; Torre, Ida; Righi, Elena; Farruggia, Patrizia; Tesauro, Marina; Torregrossa, Maria V; Montagna, Maria T; Colucci, Maria E; Gallè, Francesca; Masia, Maria D; Strohmenger, Laura; Bergomi, Margherita; Tinteri, Carola; Panico, Manuela; Pennino, Francesca; Cannova, Lucia; Tanzi, Marialuisa

2012-03-15

A microbiological environmental investigation was carried out in ten dental clinics in Italy. Microbial contamination of water, air and surfaces was assessed in each clinic during the five working days, for one week per month, for a three-month period. Water and surfaces were sampled before and after clinical activity; air was sampled before, after, and during clinical activity. A wide variation was found in microbial environmental contamination, both within the participating clinics and for the different sampling times. Before clinical activity, microbial water contamination in tap water reached 51,200cfu/mL (colony forming units per milliliter), and that in Dental Unit Water Systems (DUWSs) reached 872,000cfu/mL. After clinical activity, there was a significant decrease in the Total Viable Count (TVC) in tap water and in DUWSs. Pseudomonas aeruginosa was found in 2.38% (7/294) of tap water samples and in 20.06% (59/294) of DUWS samples; Legionella spp. was found in 29.96% (89/297) of tap water samples and 15.82% (47/297) of DUWS samples, with no significant difference between pre- and post-clinical activity. Microbial air contamination was highest during dental treatments, and decreased significantly at the end of the working activity (p<0.05). The microbial buildup on surfaces increased significantly during the working hours. This study provides data for the establishment of standardized sampling methods, and threshold values for contamination monitoring in dentistry. Some very critical situations have been observed which require urgent intervention. Furthermore, the study emphasizes the need for research aimed at defining effective managing strategies for dental clinics. Copyright © 2012 Elsevier B.V. All rights reserved.

Surface contamination technology in decommissioning of nuclear fuel cycle

International Nuclear Information System (INIS)

Ishiguro, Hideharu

2012-01-01

Surface contamination measurement is the most basic technology in radiation control of the nuclear and radiation facilities. Loose surface contamination causes internal exposure through airborne contamination. Surface contamination measurement is recently more important in the waste management such as confirmation of decontamination factor, contamination survey of carried-out materials from radioactive control area, and application of clearance level. This report describes the base of surface contamination standards, meaning of contamination in decommissioning, relationship between clearance level and surface contamination, and current technology of surface contamination measurement. (author)

Review of soil contamination guidance

International Nuclear Information System (INIS)

Mueller, M.A.; Kennedy, W.E. Jr.; Soldat, J.K.

1981-08-01

A review of existing and proposed radioactive soil contamination standards and guidance was conducted for United Nuclear Corporation (UNC), Office of Surplus Facilities Management. Information was obtained from both government agencies and other sources during a literature survey. The more applicable standards were reviewed, evaluated, and summarized. Information pertaining to soil contamination for both facility operation and facility decommissioning was obtained from a variety of sources. These sources included: the Code of Federal Regulations, regulatory guides, the Federal Register, topical reports written by various government agencies, topical reports written by national laboratories, and publications from the American National Standards Institute (ANSI). It was difficult to directly compare the standards and guidance obtained from these sources since each was intended for a specific situation and different units or bases were used. However, most of the information reviewed was consistent with the philosophy of maintaining exposures at levels as low as reasonably achievable

On the intrinsic gettering in Cu-contaminated Cz-Si

International Nuclear Information System (INIS)

Schmalz, K.; Kirscht, F.G.; Babanskaja, I.; Kittler, M.; Richter, H.; Seifert, W.

1985-01-01

NAA, TEM, DLTS, and EBIC investigations of Cu-contaminated Cz-Si with an intrinsic-gettering procedure realized by a multistep heat treatment demonstrate the efficiency of intrinsic gettering concerning redistribution to volume defects for Cu-contamination up to 10 16 cm -3 . The Cu-precipitation at the surface can still be suppressed for such contamination due to volume defects. However, in this case the concentration of contamination induced deep level centers at the surface is independent of the volume defect density. Only for Cu-contamination of about 10 15 cm -3 the gettering effect is strong enough to prevent the introduction of contamination induced deep levels at the surface. (author)

9 CFR 113.30 - Detection of Salmonella contamination.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of Salmonella contamination... REQUIREMENTS Standard Procedures § 113.30 Detection of Salmonella contamination. The test for detection of Salmonella contamination provided in this section shall be conducted when such a test is prescribed in an...

9 CFR 113.32 - Detection of Brucella contamination.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of Brucella contamination... REQUIREMENTS Standard Procedures § 113.32 Detection of Brucella contamination. The test for detection of Brucella contamination provided in this section shall be conducted when such a test is prescribed in an...

Novel search algorithms for a mid-infrared spectral library of cotton contaminants.

Science.gov (United States)

Loudermilk, J Brian; Himmelsbach, David S; Barton, Franklin E; de Haseth, James A

2008-06-01

During harvest, a variety of plant based contaminants are collected along with cotton lint. The USDA previously created a mid-infrared, attenuated total reflection (ATR), Fourier transform infrared (FT-IR) spectral library of cotton contaminants for contaminant identification as the contaminants have negative impacts on yarn quality. This library has shown impressive identification rates for extremely similar cellulose based contaminants in cases where the library was representative of the samples searched. When spectra of contaminant samples from crops grown in different geographic locations, seasons, and conditions and measured with a different spectrometer and accessories were searched, identification rates for standard search algorithms decreased significantly. Six standard algorithms were examined: dot product, correlation, sum of absolute values of differences, sum of the square root of the absolute values of differences, sum of absolute values of differences of derivatives, and sum of squared differences of derivatives. Four categories of contaminants derived from cotton plants were considered: leaf, stem, seed coat, and hull. Experiments revealed that the performance of the standard search algorithms depended upon the category of sample being searched and that different algorithms provided complementary information about sample identity. These results indicated that choosing a single standard algorithm to search the library was not possible. Three voting scheme algorithms based on result frequency, result rank, category frequency, or a combination of these factors for the results returned by the standard algorithms were developed and tested for their capability to overcome the unpredictability of the standard algorithms' performances. The group voting scheme search was based on the number of spectra from each category of samples represented in the library returned in the top ten results of the standard algorithms. This group algorithm was able to identify

Soil contamination of plant surfaces from grazing and rainfall interactions

International Nuclear Information System (INIS)

Hinton, T.G.; Stoll, J.M.; Tobler, L.

1995-01-01

Contaminants often attach to soil particles, and their subsequent environmental transport is largely determined by processes that govern soil movement. We examined the influence of grazing intensity on soil contamination of pastures. Four different grazing densities of sheep were tested against an ungrazed control plot. Scandium concentrations were determined by neutron activation analysis and was used as a tracer of soil adhesion on vegetation. Soil loadings ( g soil kg -1 dry plant) increased 60% when grazing intensity was increased by a factor of four (p 0.003). Rain and wind removed soil from vegetation in the ungrazed control plots, but when grazing sheep were present, an increase in rain from 0.3 to 9.7 mm caused a 130% increase in soil contamination. Multiple regression was used to develop an equation that predicts soil loadings as a function of grazing density, rainfall and wind speed (p = 0.0001, r 2 = 0.78). The model predicts that if grazing management were to be used as a tool to reduce contaminant intake from inadvertent consumption of resuspended soil by grazing animals, grazing densities would have to be reduced 2.5 times to reduce soil loadings by 50%. (author)

Electrokinetic remediation of contaminated soils: An update

International Nuclear Information System (INIS)

Lindgren, E.R.; Kozak, M.W.; Mattson, E.D.

1992-01-01

Electrokinetic remediation of chromium contaminated soil has been demonstrated for unsaturated 50-100 mesh sand with 10% moisture by weight. The initial region of sand contaminated with 100 ppm w chromate ions was completely cleansed of contamination. After 22 hours of treatment, chromate was found near the anode and apparently migrated at a rate of at least 0.40 cm/hr with a pore water current density of 2.26mA/cm 2 . An analogous run was made using the same sand and FD and C Red No. 40 as the contaminant at a molar concentration equivalent to the 100 ppm w Cr run. The position of the migrating dye was monitored photographically. After similar treatment conditions, the visual dye concentration profile exhibited characteristics similar to the chromate. The migration rate of the dye was slower than the chromate but the qualitative similarity of behavior in an electric field suggests the dye is an analog for chromate ions. The slower migration rate of the dye is not unexpected because the dye molecule is larger than chromate. The use of dye as an analog for chromate greatly accelerates the experimentation process in unsaturated soil because destructive sampling is not required to monitor the contaminant location. Experiments were also conducted to determine the effect of soil heterogeneities on the electrokinetic processes. Unsaturated sands in size fractions of 50-100 mesh (medium) and 100-200 mesh (fine) were studied both individually and in layers. The dye migration rate was accelerated in the tine sand and slowed in the medium sand of the layered experiment when compared with the corresponding individual experiments. This discrepancy was explained by estimating the current density in each layer which was proportionally higher in the fine layer and lower in the medium layer. These preliminary experiments illustrate the significant dependence of electromigration rates on current density. (author)

Bone marrow-derived cells for cardiovascular cell therapy: an optimized GMP method based on low-density gradient improves cell purity and function.

Science.gov (United States)

Radrizzani, Marina; Lo Cicero, Viviana; Soncin, Sabrina; Bolis, Sara; Sürder, Daniel; Torre, Tiziano; Siclari, Francesco; Moccetti, Tiziano; Vassalli, Giuseppe; Turchetto, Lucia

2014-09-27

Cardiovascular cell therapy represents a promising field, with several approaches currently being tested. The advanced therapy medicinal product (ATMP) for the ongoing METHOD clinical study ("Bone marrow derived cell therapy in the stable phase of chronic ischemic heart disease") consists of fresh mononuclear cells (MNC) isolated from autologous bone marrow (BM) through density gradient centrifugation on standard Ficoll-Paque. Cells are tested for safety (sterility, endotoxin), identity/potency (cell count, CD45/CD34/CD133, viability) and purity (contaminant granulocytes and platelets). BM-MNC were isolated by density gradient centrifugation on Ficoll-Paque. The following process parameters were optimized throughout the study: gradient medium density; gradient centrifugation speed and duration; washing conditions. A new manufacturing method was set up, based on gradient centrifugation on low density Ficoll-Paque, followed by 2 washing steps, of which the second one at low speed. It led to significantly higher removal of contaminant granulocytes and platelets, improving product purity; the frequencies of CD34+ cells, CD133+ cells and functional hematopoietic and mesenchymal precursors were significantly increased. The methodological optimization described here resulted in a significant improvement of ATMP quality, a crucial issue to clinical applications in cardiovascular cell therapy.

Post-consumer contamination in high-density polyethylene (HDPE) milk bottles and the design of a bottle-to-bottle recycling process.

Science.gov (United States)

Welle, F

2005-10-01

Six hundred conventional recycled HDPE flake samples, which were recollected and sorted in the UK, were screened for post-consumer contamination levels. Each analysed sample consisted of 40-50 individual flakes so that the amount of analysed individual containers was in the range 24,000-30,000 post-consumer milk bottles. Predominant contaminants in hot-washed flake samples were unsaturated oligomers, which can be also be found in virgin high-density polyethylene (HDPE) pellet samples used for milk bottle production. In addition, the flavour compound limonene, the degradation product of antioxidant additives di-tert-butylphenol and low amounts of saturated oligomers were found in higher concentrations in the post-consumer samples in comparison with virgin HDPE. However, the overall concentrations in post-consumer recycled samples were similar to or lower than concentration ranges in comparison with virgin HDPE. Contamination with other HDPE untypical compounds was rare and was in most cases related to non-milk bottles, which are HDPE and on the high cleaning efficiency of the super-clean recycling process especially for highly volatile compounds, the recycling process investigated is suitable for recycled post-consumer HDPE bottles for direct food-contact applications. However, hand-picking after automatically sorting is recommended to decrease the amount of non-milk bottles. The conclusions for suitability are valid, provided that the migration testing of recyclate contains milk bottles up to 100% and that both shelf-life testing and sensorial testing of the products are successful, which are topics of further investigations.

Standard Practice for Design and Construction of Aerospace Cleanrooms and Contamination Controlled Areas

CERN Document Server

American Society for Testing and Materials. Philadelphia

2002-01-01

1.1 The purpose of this practice is to provide design and construction guidelines for contamination controlled facilities used in the assembly and integration of aerospace hardware. The guidelines herein are intended to ensure that the facilities, when used properly, will meet the cleanliness requirements of aerospace hardware and processes. The objective is to limit contamination due to the deposition of particulate and molecular contaminants on flight hardware surfaces. 1.2 One cleanliness classification of a facility is the airborne particle concentrations in accordance with ISO 14644-1 and 14644-2. Airborne particle concentrations in accordance with FED-STD-209E are included for reference. This simple classification is inadequate to describe a facility that will support the assembly and integration of spacecraft. The extended duration of hardware exposure during fabrication and testing, the sensitivity of the hardware to hydrocarbons and other molecular contaminants, and the changing requirements during ...

Critical Review on the Public Health Impact of Norovirus Contamination in Shellfish and the Environment: A UK Perspective.

Science.gov (United States)

Hassard, Francis; Sharp, Jasmine H; Taft, Helen; LeVay, Lewis; Harris, John P; McDonald, James E; Tuson, Karen; Wilson, James; Jones, David L; Malham, Shelagh K

2017-06-01

We review the risk of norovirus (NoV) infection to the human population from consumption of contaminated shellfish. From a UK perspective, risk is apportioned for different vectors of NoV infection within the population. NoV spreads mainly by person-to-person contact or via unsanitary food handling. NoV also enters the coastal zone via wastewater discharges resulting in contamination of shellfish waters. Typically, NoV persists in the marine environment for several days, with its presence strongly linked to human population density, wastewater discharge rate, and efficacy of wastewater treatment. Shellfish bioaccumulate NoV and current post-harvest depuration is inefficient in its removal. While NoV can be inactivated by cooking (e.g. mussels), consumption of contaminated raw shellfish (e.g. oysters) represents a risk to human health. Consumption of contaminated food accounts for 3-11% of NoV cases in the UK (~74,000 cases/year), of which 16% are attributable to oyster consumption (11,800 cases/year). However, environmental and human factors influencing NoV infectivity remain poorly understood. Lack of standard methods for accurate quantification of infective and non-infective (damaged) NoV particles represent a major barrier, hampering identification of an appropriate lower NoV contamination limit for shellfish. Future management strategies may include shellfish quality assessment (at point of harvest or at point of supply) or harvesting controls. However, poor understanding of NoV inactivation in shellfish and the environment currently limits accurate apportionment and risk assessment for NoV and hence the identification of appropriate shellfish or environmental quality standards.

Decommissioning standards

International Nuclear Information System (INIS)

Crofford, W.N.

1980-01-01

EPA has agreed to establish a series of environmental standards for the safe disposal of radioactive waste through participation in the Interagency Review Group on Nuclear Waste Management (IRG). One of the standards required under the IRG is the standard for decommissioning of radioactive contaminated sites, facilities, and materials. This standard is to be proposed by December 1980 and promulgated by December 1981. Several considerations are important in establishing these standards. This study includes discussions of some of these considerations and attempts to evaluate their relative importance. Items covered include: the form of the standards, timing for decommissioning, occupational radiation protection, costs and financial provisions. 4 refs

Rehabilitation of radioactive contaminated forests

International Nuclear Information System (INIS)

Panfilov, A.V.; Uspenskaya, E.Ju.

2002-01-01

As a result of radiation accidents and nuclear-weapon tests at the territory of the former USSR a part of the Forest Fund of 23 subjects of the Russian Federation has been contaminated by radionuclides. The contaminated forests, which are included in a structure of more than 130 forest management units (leskhozes) and more then 330 local forest management units, as a rule, are located in highly inhabited regions with traditionally intensive forestry management and high level of forest resources use. To provide radiologically safe forest management in the contaminated areas, the Federal Forest Service has developed and validated a special system of countermeasures. Use of this system makes it possible to diminish significantly the dose to personnel, to exclude the use of forest products with contamination exceeding radiological standards and to provide protection of the forest as a biogeochemical barrier to radionuclide migration from contaminated areas to human habitat. (author)

Investigation of type and density of bio-aerosols in air samples from educational hospital wards of Kerman city, 2014

Directory of Open Access Journals (Sweden)

Mohammad Malakootian

2016-10-01

Full Text Available Background: Bio-aerosols in the air of hospital wards have an important role in the development of infections. It is important to make quantitative and qualitative estimations of microorganisms in the air of these wards as an index for environmental hygiene applicable to different hospital wards. The aim of the study was to investigate degrees of diversity and density of bio-aerosols in the education hospitals of Kerman city. Methods: This study applied a descriptive-cross-sectional methodology in the second half of 2014 in the education hospitals of Kerman city, with bed capacity of over 300. As many as 200 samples were collected from the air in different wards of each hospital using the standard method of the National Occupational Health and Safety Institute. Following collection, samples were placed in an incubator for 48 hours and then bio-aerosol detections were made for and resulting data reported as colonies/m3. Results: Results indicated that maximum and minimum degrees of bacterial density were observed in operation rooms and in the intensive care unit (ICU of Shafa hospital. Furthermore, comparison showedthat the operating room at Afzalipour hospital had the lowest level of fungal contamination, while ICU at Bahonar hospital had the highest level of fungal contamination. The emitted fungi of Aspergillus and Penicillium along with the bacteria, staphylococci and Acinetobacter had greater frequencies. The means of bacterial density and fungal density were not equal across the studied hospitals and significant statistical, difference was observed between means of bacterial and fungal density (P ≤ 0.001. Conclusion: Amounts of bacterial and fungal density were greater than those proposed in the American Industrial Health State Conference in 73.3% of the wards in the educational hospitals of Kerman city sampled in this study. Therefore it is suggested that implementation of some, necessary measures for continuous monitoring, promotion of

CHEMICAL CONTAMINATION AND TOXICITY ASSOCIATED WITH A COASTAL GOLF COURSE COMPLEX

Science.gov (United States)

The increasing density of golf courses represents a potential source of contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to compare the concentrations of contaminants and toxicities of sedime...

Notification determining details of technical standards concerning transport of radioisotopes or goods contaminated by radioisotopes in works or enterprises

International Nuclear Information System (INIS)

1981-01-01

This rule is established under the provisions of the regulation for the execution of the law on the prevention of radiation injuries by radioisotopes. Terms are used in this rule for the same meanings as in the regulation. The limit of the concentration of radioisotopes in the goods contaminated by these isotopes which are not required to be sealed in containers defined by the Director General of the Science and Technology Agency is 1/10,000 of the value A 2 under the notification determining the details of technical standards concerning the transport of radioisotopes or the goods contaminated by radioisotopes outside works or enterprises. The application for the permission of transporting the goods which are highly difficult to be sealed in containers shall list names and addresses, the kinds, quantities, shapes and properties of the transported goods contaminated by radioisotopes, etc. The radiation dose rate of transported goods and vehicles under the regulation is 200 milli-rem an hour on the surfaces of these goods, vehicles and containers, and 10 milli-rem an hour at the distance of 1 meter from their surfaces. The permissible exposure dose of the persons engaging in transport is 1.5 rem a year. Dangerous goods, signs, and the application for the approval of special measures are specified, respectively. (Okada, K.)

An evaluation of contaminated estuarine sites using sediment quality guidelines and ecological assessment methodologies.

Science.gov (United States)

Fulton, M; Key, P; Wirth, E; Leight, A K; Daugomah, J; Bearden, D; Sivertsen, S; Scott, G

2006-10-01

Toxic contaminants may enter estuarine ecosystems through a variety of pathways. When sediment contaminant levels become sufficiently high, they may impact resident biota. One approach to predict sediment-associated toxicity in estuarine ecosystems involves the use of sediment quality guidelines (ERMs, ERLs) and site-specific contaminant chemistry while a second approach utilizes site-specific ecological sampling to assess impacts at the population or community level. The goal of this study was to utilize an integrated approach including chemical contaminant analysis, sediment quality guidelines and grass shrimp population monitoring to evaluate the impact of contaminants from industrial sources. Three impacted sites and one reference site were selected for study. Grass shrimp populations were sampled using a push-netting approach. Sediment samples were collected at each site and analyzed for metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and pesticides. Contaminant levels were then compared to sediment quality guidelines. In general, grass shrimp population densities at the sites decreased as the ERM quotients increased. Grass shrimp densities were significantly reduced at the impacted site that had an ERM exceedance for chromium and the highest Mean ERM quotient. Regression analysis indicated that sediment chromium concentrations were negatively correlated with grass shrimp density. Grass shrimp size was reduced at two sites with intermediate levels of contamination. These findings support the use of both sediment quality guidelines and site-specific population monitoring to evaluate the impacts of sediment-associated contaminants in estuarine systems.

Risk assessment methodology for evaluating releases of radioactively contaminated materials

International Nuclear Information System (INIS)

Chen, S.Y.

1993-01-01

Extensive decontamination and decommissioning (D ampersand D) activities are expected to be required in the near future in association with license termination of nuclear power facilities and cleanup efforts at the U.S. Department of Energy's (DOE's) weapons production facilities. In advance of these D ampersand D activities, it is becoming increasingly urgent that standards be established for the release of materials with residual radioactive contamination. The only standards for unrestricted release that currently exist address surface contamination. The methods used to justify those standards were developed some 20 yr ago and may not satisfy today's criteria. Furthermore, the basis of setting standards has moved away from the traditional open-quotes instrumentation-basedclose quotes concept toward a open-quotes risk-basedclose quotes approach. Therefore, as new release standards are developed, it will be necessary that risk assessment methodology consistent with modern concepts be incorporated into the process. This paper discusses recent developments in risk methodology and issues and concerns regarding the future development of standards for the release of radioactively contaminated materials

Natural uranium toxicology - evaluation of internal contamination in man

International Nuclear Information System (INIS)

Chalabreysse, J.

1968-01-01

After reminding the physical and chemical properties of natural uranium which might affect its toxicology, a comprehensive investigation upon natural uranium metabolism and toxicity and after applying occupational exposure standards to this particular poison, it has been determined, from accident reports and human experience reported in the related literature, a series of formulae obtained by theoretical mathematical development giving principles for internal contamination monitoring and disclosure by determining uranium in the urine of occupationally exposed individuals. An assay is performed to determine individual internal contamination according to the various contamination cases. The outlined purposes, mainly practical, required some options and extrapolations. The proposed formula allows a preliminary approach and also to determine shortly a contamination extent or to discuss the systematical urinalysis results as compared with individual radio-toxicology monitoring professional standards. (author) [fr

Comparative evaluations of surface contamination detectors calibration with radioactive sources - used in the Goiania accident, and standard sources; Estudo comparativo da calibracao dos monitores de contaminacao superficial com as fontes radiativas utilizadas durante o acidente de Goiania e com fontes padrao

Energy Technology Data Exchange (ETDEWEB)

Becker, P.H.B.; Marecha, M.H.H. [Instituto de Radioprotecao e Dosimetria (IRD), Rio de Janeiro, RJ (Brazil)

1997-12-31

The construction of Cs-137 standard flat sources for calibration of surface contamination detectors, used in the Goiania accident in 1987, is described and the procedures adopted are reported. At that time, standard sources were not available. Nowadays the Instituto de Radioprotecao e Dosimetria has standard sources acquired from Amersham which are used as calibration standards for surface contamination detectors. Comparative evaluations between the standard flat sources constructed for the accident and the calibrated ones are presented 6 refs., 1 fig., 4 tabs.; e-mail: pbecker at ird.gov.br; mhelena at ird. gov.br

Simultaneous Reduction in Noise and Cross-Contamination Artifacts for Dual-Energy X-Ray CT

Directory of Open Access Journals (Sweden)

Baojun Li

2013-01-01

Full Text Available Purpose. Dual-energy CT imaging tends to suffer from much lower signal-to-noise ratio than single-energy CT. In this paper, we propose an improved anticorrelated noise reduction (ACNR method without causing cross-contamination artifacts. Methods. The proposed algorithm diffuses both basis material density images (e.g., water and iodine at the same time using a novel correlated diffusion algorithm. The algorithm has been compared to the original ACNR algorithm in a contrast-enhanced, IRB-approved patient study. Material density accuracy and noise reduction are quantitatively evaluated by the percent density error and the percent noise reduction. Results. Both algorithms have significantly reduced the noises of basis material density images in all cases. The average percent noise reduction is 69.3% and 66.5% with the ACNR algorithm and the proposed algorithm, respectively. However, the ACNR algorithm alters the original material density by an average of 13% (or 2.18 mg/cc with a maximum of 58.7% (or 8.97 mg/cc in this study. This is evident in the water density images as massive cross-contaminations are seen in all five clinical cases. On the contrary, the proposed algorithm only changes the mean density by 2.4% (or 0.69 mg/cc with a maximum of 7.6% (or 1.31 mg/cc. The cross-contamination artifacts are significantly minimized or absent with the proposed algorithm. Conclusion. The proposed algorithm can significantly reduce image noise present in basis material density images from dual-energy CT imaging, with minimized cross-contaminations compared to the ACNR algorithm.

Investigations of the transport behavior of contaminants in fresh water/brine systems under consideration of density differences; Untersuchungen zum Transportverhalten von Schadstoffen in Suess- / Salzwassersystemen unter Beruecksichtigung von Dichteunterschieden

Energy Technology Data Exchange (ETDEWEB)

Larue, Juergen; Weyand, Torben; Mayer, Kim-Marisa

2016-10-15

This report contains a compilation of national and international experience gathered as part of a research project sponsored by the BMUB concerning the aspect of the transport behaviour of contaminants in freshwater/brine systems with consideration of density and viscosity differences. The fundamentals of modelling density-dependent flows are presented and a series of examples of the application with different codes and their uses with reference to real sites is described. Besides an overview of test cases for the verification of these codes, the further development of the instruments available to GRS and test calculations regarding their implementation are presented.

Treatment of chromium contaminated soil using bioremediation

Science.gov (United States)

Purwanti, Ipung Fitri; Putri, Tesya Paramita; Kurniawan, Setyo Budi

2017-11-01

Chromium contamination in soil occurs due to the disposal of chromium industrial wastewater or sludge that excess the quality standard. Chromium concentration in soil is ranged between 1 to 300 mg/kg while the maximum health standard is 2.5 mg/kg. Bioremediation is one of technology that could be used for remediating heavy metal contamination in soil. Bacteria have an ability to remove heavy metal from soil. One bacteria species that capable to remove chromium from soil is Bacillus subtilis. The aim of this research was to know the chromium removal percentage in contaminated soil by Bacillus subtilis. Artificial chromium contaminated soil was used by mixing 425gram sand and chromium trichloride solution. Concentration of chromium added into the spiked soil were 50, 75, and 100 mg/L. During 14 days, pH, soil temperature and soil moisture were tested. Initial and final number of bacterial colony and chromium concentration analysed. The result showed that the highest percentage of chromium removal was 11% at a chromium concentration of 75 mg/L

SEDIMENT CHEMICAL CONTAMINATION AND TOXICITY ASSOCIATED WITH A COASTAL GOLF COURSE COMPLEX.

Science.gov (United States)

The increasing density of golf courses represents a potential source of sediment contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to determine the concentrations of contaminants and toxicities...

Nano-TiO2-based photocatalytic disinfection of environmental surfaces contaminated by meticillin-resistant Staphylococcus aureus.

Science.gov (United States)

Petti, S; Messano, G A

2016-05-01

Traditional cleaning and disinfection methods are inefficient for complete decontamination of hospital surfaces from meticillin-resistant Staphylococcus aureus (MRSA). Additional methods, such as nano-TiO2-based photocatalytic disinfection (PCD), could be helpful. To evaluate anti-MRSA activity of PCD on polyvinyl chloride (PVC) surfaces in natural-like conditions. Two identical PVC surfaces were used, and nano-TiO2 was incorporated into one of them. The surfaces were contaminated with MRSA isolated from hospitalized patients using a mist sprayer to simulate the mode of environmental contamination caused by a carrier. MRSA cell density was assessed before contamination until 180min after contamination using Rodac plates. The differences between test and control surfaces in terms of MRSA density and log MRSA density reduction were assessed using parametric and non-parametric statistical tests. Five strains were tested, and each strain was tested five times. The highest median MRSA densities [46.3 and 43.1 colony-forming units (cfu)/cm(2) for control and test surfaces, respectively] were detected 45min after contamination. Median MRSA densities 180min after contamination were 10.1 and 0.7cfu/cm(2) for control and test surfaces, respectively (Pdisinfectant activity remained stable throughout the 25 testing occasions, despite between-test cleaning and disinfection. The anti-MRSA activity of PCD was compatible with the benchmark for surface hygiene in hospitals (surfaces. However, for clinical surfaces, PCD should be regarded as supplemental to conventional decontamination procedures, rather than an alternative. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Contamination of herbal medicinal products marketed in Kaduna ...

African Journals Online (AJOL)

The study aimed to evaluate the bacterial contamination of powdered herbal medicinal preparations sourced from identified herbal retail outlets in different parts of Kaduna metropolis. The assessments of the contamination of the herbal products were carried out using standard procedures: total aerobic bacterial plate count, ...

Aging effects on oil-contaminated Kuwaiti sand

International Nuclear Information System (INIS)

Al-Sanad, H.A.; Ismael, N.F.

1997-01-01

Large quantities of oil-contaminated sands resulted from the destruction of oil wells and the formation of oil lakes in Kuwait at the end of the Gulf Wa/r. A laboratory testing program was carried out to determine the geotechnical properties of this material and the effect of aging on their properties. Tests included direct shear, triaxial, and consolidation tests on clean and contaminated sand at the same relative density. The influence of aging was examined by testing uncontaminated sand after aging for one, three, and six months in natural environmental conditions. The results indicated increased strength and stiffness due to aging and a reduction of the oil content due to evaporation of volatile compounds. The factors that influence the depth of oil penetration in compacted sand columns were also examined including the type of oil, relative density, and the amount of fines

Estimating dermal transfer from PCB-contaminated porous surfaces.

Science.gov (United States)

Slayton, T M; Valberg, P A; Wait, A D

1998-06-01

Health risks posed by dermal contact with PCB-contaminated porous surfaces have not been directly demonstrated and are difficult to estimate indirectly. Surface contamination by organic compounds is commonly assessed by collecting wipe samples with hexane as the solvent. However, for porous surfaces, hexane wipe characterization is of limited direct use when estimating potential human exposure. Particularly for porous surfaces, the relationship between the amount of organic material collected by hexane and the amount actually picked up by, for example, a person's hand touch is unknown. To better mimic PCB pickup by casual hand contact with contaminated concrete surfaces, we used alternate solvents and wipe application methods that more closely mimic casual dermal contact. Our sampling results were compared to PCB pickup using hexane-wetted wipes and the standard rubbing protocol. Dry and oil-wetted samples, applied without rubbing, picked up less than 1% of the PCBs picked up by the standard hexane procedure; with rubbing, they picked up about 2%. Without rubbing, saline-wetted wipes picked up 2.5%; with rubbing, they picked up about 12%. While the nature of dermal contact with a contaminated surface cannot be perfectly reproduced with a wipe sample, our results with alternate wiping solvents and rubbing methods more closely mimic hand contact than the standard hexane wipe protocol. The relative pickup estimates presented in this paper can be used in conjunction with site-specific PCB hexane wipe results to estimate dermal pickup rates at sites with PCB-contaminated concrete.

Final report on CCM key comparison CCM.D-K2: Comparison of liquid density standards

Science.gov (United States)

Bettin, Horst; Jacques, Claude; Zelenka, Zoltán; Fujii, Ken-ichi; Kuramoto, Naoki; Chang, Kyung-Ho; Lee, Yong Jae; Becerra, Luis Omar; Domostroeva, Natalia

2013-01-01

The results are presented of the key comparison CCM.D-K2 that covered the density measurements of four liquids: the density of water at 20 °C, of pentadecane at 15 °C, 20 °C, 40 °C and 60°C, of tetrachloroethlyene at 5 °C and 20 °C and of a viscous oil at 20 °C. Seven national metrology institutes measured the densities at atmospheric pressure by hydrostatic weighing of solid density standards in the time interval from 27 April 2004 to 28 June 2004. Since the participants were asked not to include components for a possible drift or inhomogeneity of the liquid in their uncertainty budget, these uncertainty contributions are investigated for the final evaluation of the data. For this purpose, results of stability and homogeneity measurements of the pilot laboratory are used. The participants decided not to include a possible drift of the liquid's density since no significant drift could be detected, and the influence of the drift and its uncertainty are negligible. Similarly, the inhomogeneity of the water and pentadecane samples is not significant and has no influence on the evaluation. Thus, it was neglected. Only the inhomogeneities of tetrachloroethylene and of the viscous oil were significant. Consequently, they were included in the evaluation. With one or two exceptions, the results show good agreement among the participants. Only in the case of water are the results clearly discrepant. The key comparison reference values were calculated by the weighted mean (taking into account a small correlation between two participants) in the case of consistent results. Otherwise the Procedure B of Cox was used. The expanded uncertainties of all reference densities are below 1 × 10-5 in relative terms. This satisfies the needs of all customers who wish to calibrate or check liquid density measuring instruments such as oscillation-type density meters. The comparison fully supports the calibration measurement capabilities table in the BIPM key comparison database

Indexing contamination surveys

International Nuclear Information System (INIS)

Brown, R.L.

1998-01-01

The responsibility for safely managing the Tank Farms at Hanford belongs to Lockheed Martin Hanford Corporation which is part of the six company Project Hanford Management Team led by Fluor Daniel Hanford, Inc.. These Tank Farm Facilities contain numerous outdoor contamination areas which are surveyed at a periodicity consistent with the potential radiological conditions, occupancy, and risk of changes in radiological conditions. This document describes the survey documentation and data tracking method devised to track the results of contamination surveys this process is referred to as indexing. The indexing process takes a representative data set as an indicator for the contamination status of the facility. The data are further manipulated into a single value that can be tracked and trended using standard statistical methodology. To report meaningful data, the routine contamination surveys must be performed in a manner that allows the survey method and the data collection process to be recreated. Three key criteria are necessary to accomplish this goal: Accurate maps, consistent documentation, and consistent consolidation of data meeting these criteria provides data of sufficient quality to be tracked. Tracking of survey data is accomplished by converting the individual survey results into a weighted value, corrected for the actual number of survey points. This information can be compared over time using standard statistical analysis to identify trends. At the Tank Farms, the need to track and trend the facility's radiological status presents unique challenges. Many of these Tank Farm facilities date back to the second world war. The Tank Farm Facilities are exposed to weather extremes, plant and animal intrusion, as well as all of the normal challenges associated with handling radiological waste streams. Routine radiological surveys did not provide a radiological status adequate for continuing comparisons

Radioecological conditions in the towns, where the status of radioactive contamination zones will change

International Nuclear Information System (INIS)

Ageeva, T.N.; Shapsheeva, T.P.; Zajtsev, A.A.; Makarevich, I.A.

2015-01-01

The article presents data of changes in the density of soil contamination in settlements where in 2015 change of the status of contaminated areas is possible. Article contains analysis of monitoring of radioactive contamination of food from private farms, the results of radio ecological inspection conducted in 2013-2014. (authors)

Experimental study on source efficiencies for estimating surface contamination level

International Nuclear Information System (INIS)

Ichiji, Takeshi; Ogino, Haruyuki

2008-01-01

Source efficiency was measured experimentally for various materials, such as metals, nonmetals, flooring materials, sheet materials and other materials, contaminated by alpha and beta emitter radioactive nuclides. Five nuclides, 147 Pm, 60 Co, 137 Cs, 204 Tl and 90 Sr- 90 Y, were used as the beta emitters, and one nuclide 241 Am was used as the alpha emitter. The test samples were prepared by placing drops of the radioactive standardized solutions uniformly on the various materials using an automatic quantitative dispenser system from Musashi Engineering, Inc. After placing drops of the radioactive standardized solutions, the test materials were allowed to dry for more than 12 hours in a draft chamber with a hood. The radioactivity of each test material was about 30 Bq. Beta rays or alpha rays from the test materials were measured with a 2-pi gas flow proportional counter from Aloka Co., Ltd. The source efficiencies of the metals, nonmetals and sheet materials were higher than 0.5 in the case of contamination by the 137 Cs, 204 Tl and 90 Sr- 90 Y radioactive standardized solutions, higher than 0.4 in the case of contamination by the 60 Co radioactive standardized solution, and higher than 0.25 in the case of contamination by the alpha emitter the 241 Am radioactive standardized solution. These values were higher than those given in Japanese Industrial Standards (JIS) documents. In contrast, the source efficiencies of some permeable materials were lower than those given in JIS documents, because source efficiency varies depending on whether the materials or radioactive sources are wet or dry. This study provides basic data on source efficiency, which is useful for estimating the surface contamination level of materials. (author)

The recuperation of sulphuric acid out of contaminated solutions by electro electrodialysis

International Nuclear Information System (INIS)

Cattoir, S.

1997-05-01

The dismantling of a nuclear reactor results in large amounts of contaminated waste. The amount of waste is minimized by so-called decontamination processes. These decontamination processes result in decontaminated metal as well as contaminated effluents, containing acid and metal salts. Standard treatment of these effluents involves neutralisation of the acid using sodium hydroxide, resulting in the precipitation of hydroxides; and evaporation of the solvent. However, if the acid is extracted out of the decontamination effluents prior to neutralisation, this acid can be re-used in the decontamination process, substantially reducing the final waste. This report investigates the possibility of using Electro Electrodialysis (EED) for the extraction of 900 moles of sulphuric acid out of a 1 m 3 contaminated solution, containing 22 kg of ferrous, chromous, cerous and nickel ions and 1000 moles of sulphuric acid. EED removes acids out of acid/salts solutions, using an electrolyser equipped with an anionic membrane: the acid-anion is displaced by migration through the membrane while the proton is displaced by electrolysis. This report gives a full description of the technique, the lab-scale apparatus, the analyses involved in studying the technique on lab-scale or monitoring it on full scale, the choice of electrode and membrane and of process parameters such as temperature and current density. On lab scale, EED can displace 90% of the acid out of the acid/salt solution just described, at a current density as high as 0.14 A.cm -2 , at 50 degrees Celsius, if the cathode and the anode are of smoothed platina or of platinised titanium, and the anion selective membrane is the Neosepta AMH -membrane of Tokuyama. The study of EED still needs to be completed with a further study of metal deposition on the cathode, and a comparison of the technique to other (electro)membrane techniques

Emerging contaminants: Presentations at the 2009 Toxicology and Risk Assessment Conference

International Nuclear Information System (INIS)

Murnyak, George; Vandenberg, John; Yaroschak, Paul J.; Williams, Larry; Prabhakaran, Krishnan; Hinz, John

2011-01-01

A session entitled 'Emerging Contaminants' was held in April 2009 in Cincinnati, OH at the 2009 Toxicology and Risk Assessment Conference. The purpose of the session was to share information on both programmatic and technical aspects associated with emerging contaminants. Emerging contaminants are chemicals or materials that are characterized by a perceived or real threat to human health or environment, a lack of published health standards or an evolving standard. A contaminant may also be 'emerging' because of the discovery of a new source, a new pathway to humans, or a new detection method or technology. The session included five speakers representing the Department of Defense (DoD), the Environmental Protection Agency (EPA), and each of the military services. The DoD created the Emerging Contaminant Directorate to proactively address environmental, health, and safety concerns associated with emerging contaminants. This session described the scan-watch-action list process, impact assessment methodology, and integrated risk management concept that DoD has implemented to manage emerging contaminants. EPA presented emerging trends in health risk assessment. Researchers made technical presentations on the status of some emerging contaminates in the assessment process (i.e. manganese, RDX, and naphthalene).

Public views on drinking water standards as risk indicators.

Science.gov (United States)

Johnson, Branden B

2008-12-01

Government agencies often compare contaminant levels to standards and other regulatory benchmarks to convey relative risk to public audiences, as well as for enforcement. Yet we know little of how citizens interpret these risk indicators or factors influencing interpretations. Owners of private residential wells in New Jersey were surveyed by mail. A majority appreciated this comparison, trusted the standard, and could effectively compare the contaminant level to the standard. Most people who recalled that their own well water quality was unsatisfactory simply installed treatment systems. However, there was also a surprising amount of inability to tell whether pollution levels were better or worse than the standard, perhaps exacerbated by confusing institutional language to summarize the comparison (e.g., pollution "exceeds" or is "less than" the standard) and innumeracy. There was also substantial skepticism about the degree to which pollution levels below, or (to a lesser extent) above, the standard are harmless or harmful, respectively. Skepticism was variously due to distrust of standards, disbelief in thresholds for health effects, inability to accurately compare standards and contaminant levels, information processing, and demographics. Discontinuity in reactions below versus above the standard did not exist in the aggregate, and rarely among individuals, contrary to some previous findings. At identical standards and contaminant levels, familiar toxins (mercury, arsenic, lead) elicited higher risk ratings than less familiar ones. Given the wide institutional use of this risk indicator, further research on how to improve the design and use of this indicator, and consideration of alternatives, is warranted.

29 CFR 1910.19 - Special provisions for air contaminants.

Science.gov (United States)

2010-07-01

... 29 Labor 5 2010-07-01 2010-07-01 false Special provisions for air contaminants. 1910.19 Section 1910.19 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION... Standards § 1910.19 Special provisions for air contaminants. (a) Asbestos, tremolite, anthophyllite, and...

Proposal of traceability chain for direct measurements of radioactive contamination in Cuba

International Nuclear Information System (INIS)

Walwyn Salas, Gonzalo; Tamayo Garcia, Jose A.; Cornejo Diaz, Nestor

2008-01-01

The measurements of the radioactive surface contamination are common used to demonstrate the compliance with safety regulations at national level. It is mandatory that those measurements are traceable to national standards through the suitable calibration of the monitors used for survey. In Cuba, there is not a harmonized methodology for evaluation of contamination from direct measurements and no standardized calibration service for portable monitors is routinely provided to users. The Secondary Standard Dosimetry Laboratory of Cuba has recently established the calibration service of contamination monitors in terms of instrument efficiency using the reference sources of known emission rate per unit area in accordance with international normative ISO 8769. In the present paper, is proposed a traceable scheme of direct measurements of contamination that involve the calibration at the laboratory level using multi-source method and the evaluation of contaminations at user level in terms of activity per unit area. Some improvements from the previous single-source method of calibration are explained in order to support the advantages that offer the new chain for those measurements in the country. (author)

Microbial Contamination of Pastry Cream: Evidence from Iran

Directory of Open Access Journals (Sweden)

Mohamadreza Pajohi-alamoti

2016-07-01

Full Text Available Background & Aims of the Study: Given the importance of microbial contamination in creating food-borne diseases, this study was conducted to assess level of microbial contamination of pastry creams in Hamedan, Iran. Materials and Methods: Totally, 80 samples were randomly collected from the confectioneries and analyzed for microbial contamination according to Iranian national standard microbial tests. Results: Data indicated that 49 (61.2% samples were contaminated, mostly comprised of Coliforms (92.5%. Moreover, the infection was seen to be higher in jelly roll compared to puff pastry. Yeast contamination was about 82.5 percent, which could accelerate the decay of such products. However, yeast contamination of puff pastries was higher than jelly roll. The microbial contamination with Staphylococcus aureus, total viable count and molds were 57.5%, 35% and 37.5%; respectively. Conclusion: Nevertheless, Salmonella, Escherichia coli and Listeria monocytogenes were not found in any of the samples. Abundance of microbial contamination in the puff pastry samples might put consumer’s health at risk.

Plutonium contamination in the Maralinga Tjarutja lands

International Nuclear Information System (INIS)

Johnston, P.N.; Lokan, K.H.; Richardson, C.K.; Williams, G.A.

1989-08-01

Nuclear weapons trials conducted at Maralinga from 1960 to 1963 resulted in contamination of large areas of land with low levels of plutonium. Ground and aerial surveys and soil sampling conducted between 1984 and 1987 showed that this contamination extended beyond the boundaries of the area still controlled by the Commonwealth Government into the Maralinga Tjarutja lands. Levels of contamination beyond the boundaries of the former test range were found to be low, and were generally undetectable for all but the most sensitive measurement techniques. Soil sampling combined with long laboratory counting was initially used to define the trace levels but the contamination was found to be particulate with a surface density of particles too low for this to be a generally useful technique. The results are presented of in-situ gamma-ray spectrometry using a portable germanium (Ge) detector to measure contamination levels of plutonium to well below 1 kBq m -2 in the Maralinga Tjarutja lands to the north and north-west of the Maralinga test site. 8 refs., 10 figs., 10 tabs

Explosive Contamination from Substrate Surfaces: Differences and Similarities in Contamination Techniques Using RDX and C-4

Science.gov (United States)

Miller, C. J.; Yoder, T. S.

2010-06-01

Explosive trace detection equipment has been deployed to airports for more than a decade. During this time, the need for standardized procedures and calibrated trace amounts for ensuring that the systems are operating properly and detecting the correct explosive has been apparent but a standard representative of a fingerprint has been elusive. Standards are also necessary to evaluate instrumentation in the laboratories during development and prior to deployment to determine sample throughput, probability of detection, false positive/negative rates, ease of use by operator, mechanical and/or software problems that may be encountered, and other pertinent parameters that would result in the equipment being unusable during field operations. Since many laboratories do not have access to nor are allowed to handle explosives, the equipment is tested using techniques aimed at simulating the actual explosives fingerprint. This laboratory study focused on examining the similarities and differences in three different surface contamination techniques that are used to performance test explosive trace detection equipment in an attempt to determine how effective the techniques are at replicating actual field samples and to offer scenarios where each contamination technique is applicable. The three techniques used were dry transfer deposition of standard solutions using the Transportation Security Laboratory’s (TSL) patented dry transfer techniques (US patent 6470730), direct deposition of explosive standards onto substrates, and fingerprinting of actual explosives onto substrates. RDX was deposited on the surface of one of five substrates using one of the three different deposition techniques. The process was repeated for each substrate type using each contamination technique. The substrate types used were: 50% cotton/50% polyester as found in T-shirts, 100% cotton with a smooth surface such as that found in a cotton dress shirt, 100% cotton on a rough surface such as that

Local anthropogenic contamination affects the fecundity and reproductive success of an Arctic amphipod

NARCIS (Netherlands)

Bach, L.; Fischer, A.; Strand, J.

2010-01-01

This study investigates whether adaptation to life in contaminated Arctic areas carries a cost for the populations in terms of reduced fecundity and reproductive success. The benthic amphipod, Orchomenella pinguis occurs in huge densities in both clean and contaminated sites. O. pinguis was

Sensitivity to contamination of optical coatings

International Nuclear Information System (INIS)

Macleod, A.

1999-01-01

A simple theory is presented of the sensitivity to contamination of optical coatings, which permits prediction of performance degradation in the presence of small deposit s of absorbing material. Although a major objective is the ability to compare the sensitivities of different coating types, absolute values can be made possible by adopting a standard contamination layer consisting of a 1 Angstrom thickness of carbon. Results are quoted for a number of common thin-film coatings and filters and are sometimes surprising. The common high-reflectance coating is the quarterwave stack and, at its reference wavelength, it has very low sensitivity to contamination. Although minor constructional errors have little effect on the reflectance, they can seriously affect the contamination sensitivity. Further, the level of contamination determines the maximum reflectance it is possible to achieve, regardless of the number of layers in the coating. The admittance diagram helps in understanding the reasons for the very large variations in sensitivity between coatings with quite similar reflectance

Telemetry Standards, RCC Standard 106-17. Chapter 8. Digital Data Bus Acquisition Formatting Standard

Science.gov (United States)

2017-07-01

incorrect word count/message and illegal mode codes are not considered bus errors. 8.6.2 Source Signal The source of data is a signal conforming to...Telemetry Standards, RCC Standard 106-17 Chapter 8, July 2017 CHAPTER 8 Digital Data Bus Acquisition Formatting Standard Acronyms...check FCS frame check sequence HDDR high-density digital recording MIL-STD Military Standard msb most significant bit PCM pulse code modulation

Methodology for performing surveys for fixed contamination

International Nuclear Information System (INIS)

Durham, J.S.; Gardner, D.L.

1994-10-01

This report describes a methodology for performing instrument surveys for fixed contamination that can be used to support the release of material from radiological areas, including release to controlled areas and release from radiological control. The methodology, which is based on a fast scan survey and a series of statistical, fixed measurements, meets the requirements of the U.S. Department of Energy Radiological Control Manual (RadCon Manual) (DOE 1994) and DOE Order 5400.5 (DOE 1990) for surveys for fixed contamination and requires less time than a conventional scan survey. The confidence interval associated with the new methodology conforms to the draft national standard for surveys. The methodology that is presented applies only to surveys for fixed contamination. Surveys for removable contamination are not discussed, and the new methodology does not affect surveys for removable contamination

Bacteria associated with contamination of ready-to-eat (RTE ...

African Journals Online (AJOL)

The bacteria associated with contamination of ready-to-eat (RTE) cooked rice in Lagos, Nigeria were studied using standard microbiological methods. The objective of this study was to investigate the distribution of pathogenic bacteria recovered from RTE cooked rice in Lagos, assess bacteria load in the contaminated RTE ...

Concentration and toxicity of sea-surface contaminants in Puget Sound

Energy Technology Data Exchange (ETDEWEB)

Hardy, J.T.; Crecelius, E.A.; Kocan, R.

1986-04-01

The Marine Research Laboratory conducted studies during CY 1985 to evaluate the effects of sea-surface contamination on the reproductive success of a valued marine species. Microlayer and bulk water samples were collected from a rural bay, central Puget Sound, and three urban bays and analyzed for a number of metal and organic contaminants as well as for densities of neuston and plankton organisms. Fertilized neustonic eggs of sand sole (Psettichthys melanostictus) were exposed to the same microlayer samples during their first week of embryonic and larval development. Also, we evaluated the effects of microlayer extracts on the growth of trout cell cultures. Compared to rural sites, urban bays generally contained lower densities of neustonic flatfish eggs during the spawning season. Also, in contrast to the rural sites or the one central Puget Sound site, approximately half of the urban bay microlayer samples resulted in significant increases in embryo mortality (up to 100%), kyphosis (bent spine abnormalities) in hatched larvae, increased anaphase aberrations in developing embryos, and decreased trout cell growth. The toxic samples generally contained high concentrations of polycyclic aromatic and/or chlorinated hydrocarbons and/or potentially toxic metals. In some cases, concentrations of contaminants on the sea surface exceeded water-quality criteria by several orders of magnitude. Several samples of subsurface bulk water collected below highly contaminated surfaces showed no detectable contamination or toxicity.

Reineke’s stand density index: a quantitative and non-unitless measure of stand density

Science.gov (United States)

Curtis L. VanderSchaaf

2013-01-01

When used as a measure of relative density, Reineke’s stand density index (SDI) can be made unitless by relating the current SDI to a standard density but when used as a quantitative measure of stand density SDI is not unitless. Reineke’s SDI relates the current stand density to an equivalent number of trees per unit area in a stand with a quadratic mean diameter (Dq)...

Light Obscuration Particle Counter Fuel Contamination Limits

Science.gov (United States)

2015-10-08

two methods for measuring particulate contamination by gravimetric analysis: ASTM D2276 - Standard Test Method for Particulate Contaminant in Aviation...problems with the gravimetric methods is the poor repeatability and reproducibility of the methods , ASTM D2276 has a repeatability of 0.25 mg/L and...collected failing either the particle count or the gravimetric limit, 314 of which failed both methods . 245 false negatives were recorded where the

Groundwater arsenic contamination throughout China.

Science.gov (United States)

Rodríguez-Lado, Luis; Sun, Guifan; Berg, Michael; Zhang, Qiang; Xue, Hanbin; Zheng, Quanmei; Johnson, C Annette

2013-08-23

Arsenic-contaminated groundwater used for drinking in China is a health threat that was first recognized in the 1960s. However, because of the sheer size of the country, millions of groundwater wells remain to be tested in order to determine the magnitude of the problem. We developed a statistical risk model that classifies safe and unsafe areas with respect to geogenic arsenic contamination in China, using the threshold of 10 micrograms per liter, the World Health Organization guideline and current Chinese standard for drinking water. We estimate that 19.6 million people are at risk of being affected by the consumption of arsenic-contaminated groundwater. Although the results must be confirmed with additional field measurements, our risk model identifies numerous arsenic-affected areas and highlights the potential magnitude of this health threat in China.

The virialization density of peaks with general density profiles under spherical collapse

OpenAIRE

Rubin, Douglas; Loeb, Abraham

2013-01-01

We calculate the non-linear virialization density, $\\Delta_c$, of halos under spherical collapse from peaks with an arbitrary initial and final density profile. This is in contrast to the standard calculation of $\\Delta_c$ which assumes top-hat profiles. Given our formalism, the non-linear halo density can be calculated once the shape of the initial peak's density profile and the shape of the virialized halo's profile are provided. We solve for $\\Delta_c$ for halos in an Einstein de-Sitter an...

Remediation of lead-contaminated soils

International Nuclear Information System (INIS)

Peters, R.W.; Shem, L.

1992-01-01

Excavation and transport of soil contaminated with heavy metals has generally been the standard remediation technique for treatment of heavy-metal-contaminated soils. This approach is not a permanent solution; moreover, off-site shipment and disposal of contaminated soil involves high expense, liability, and appropriate regulatory approval. Recently, a number of other techniques have been investigated for treating such contaminated sites, including flotation, solidification/stabilization, vitrification, and chemical extraction. This paper reports the results of a laboratory investigation determining the efficiency of using chelating agents to extract lead from contaminated soils. Lead concentrations in the soils ranged from 500 to 10,000 mg/kg. Ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) were examined for their potential extractive capabilities. Concentrations of the chelating agents ranged from 0.01 to 0.10 M. The pH of the suspensions in which the extractions were performed ranged from 4 to 12. Results showed that the removal of lead using NTA and water was ph-dependent, whereas the removal of lead using EDTA was ph-insensitive. Maximum removals of lead were 68.7%,19.1%, and 7.3% using EDTA, NTA, and water, respectively (as compared with initial lead concentrations)

Clean-up criteria for remediation of contaminated soils

International Nuclear Information System (INIS)

Nguyen, H.D.; Wilson, J.R.; Sato, Chikashi

1997-01-01

'How clean is clean?' is a question commonly raised in the remediation of contaminated soils. To help with the answer, criteria are proposed to serve as guidelines for remedial actions and to define a clean-up level such that the remaining contaminant residuals in the soil will not violate the Drinking Water Standards (DWS). The equations for computing those criteria are developed from the principle of conservation of mass and are functions of the maximum concentration level in the water (MCL) and the sorption coefficient. A multiplier, ranging from 10 to 1000, is also factored into the soil standard equation to reflect the effectiveness of various remediation techniques. Maximum allowable concentration in the soil (MSCL) is presented for several contaminants which are being regulated at the present time. Future modifications are recommended for better estimates of the MSCLs as additional transport mechanisms are incorporated to account for other potentially dominant effects

A transportable system for radioactivity contaminated water treatment

International Nuclear Information System (INIS)

2013-01-01

Contaminated water treatment system called SARRY for retrieval and recovery of water in operation at the site of Fukushima Daiichi Nuclear Power Plant since August 2011 has been modified by compacting the system size to develop a mobile system SARRY-Aqua that can process Cs-contaminated water (one ton/hour) to the level of 10 Bq/kg. Installing the system in a small container with dimensions conforming to the international standards facilitates transportation by truck and enables the contaminated water treatment occurring in a variety of locations. (S. Ohno)

The Harvard Automated Processing Pipeline for Electroencephalography (HAPPE): Standardized Processing Software for Developmental and High-Artifact Data.

Science.gov (United States)

Gabard-Durnam, Laurel J; Mendez Leal, Adriana S; Wilkinson, Carol L; Levin, April R

2018-01-01

Electroenchephalography (EEG) recordings collected with developmental populations present particular challenges from a data processing perspective. These EEGs have a high degree of artifact contamination and often short recording lengths. As both sample sizes and EEG channel densities increase, traditional processing approaches like manual data rejection are becoming unsustainable. Moreover, such subjective approaches preclude standardized metrics of data quality, despite the heightened importance of such measures for EEGs with high rates of initial artifact contamination. There is presently a paucity of automated resources for processing these EEG data and no consistent reporting of data quality measures. To address these challenges, we propose the Harvard Automated Processing Pipeline for EEG (HAPPE) as a standardized, automated pipeline compatible with EEG recordings of variable lengths and artifact contamination levels, including high-artifact and short EEG recordings from young children or those with neurodevelopmental disorders. HAPPE processes event-related and resting-state EEG data from raw files through a series of filtering, artifact rejection, and re-referencing steps to processed EEG suitable for time-frequency-domain analyses. HAPPE also includes a post-processing report of data quality metrics to facilitate the evaluation and reporting of data quality in a standardized manner. Here, we describe each processing step in HAPPE, perform an example analysis with EEG files we have made freely available, and show that HAPPE outperforms seven alternative, widely-used processing approaches. HAPPE removes more artifact than all alternative approaches while simultaneously preserving greater or equivalent amounts of EEG signal in almost all instances. We also provide distributions of HAPPE's data quality metrics in an 867 file dataset as a reference distribution and in support of HAPPE's performance across EEG data with variable artifact contamination and

The Harvard Automated Processing Pipeline for Electroencephalography (HAPPE: Standardized Processing Software for Developmental and High-Artifact Data

Directory of Open Access Journals (Sweden)

Laurel J. Gabard-Durnam

2018-02-01

Full Text Available Electroenchephalography (EEG recordings collected with developmental populations present particular challenges from a data processing perspective. These EEGs have a high degree of artifact contamination and often short recording lengths. As both sample sizes and EEG channel densities increase, traditional processing approaches like manual data rejection are becoming unsustainable. Moreover, such subjective approaches preclude standardized metrics of data quality, despite the heightened importance of such measures for EEGs with high rates of initial artifact contamination. There is presently a paucity of automated resources for processing these EEG data and no consistent reporting of data quality measures. To address these challenges, we propose the Harvard Automated Processing Pipeline for EEG (HAPPE as a standardized, automated pipeline compatible with EEG recordings of variable lengths and artifact contamination levels, including high-artifact and short EEG recordings from young children or those with neurodevelopmental disorders. HAPPE processes event-related and resting-state EEG data from raw files through a series of filtering, artifact rejection, and re-referencing steps to processed EEG suitable for time-frequency-domain analyses. HAPPE also includes a post-processing report of data quality metrics to facilitate the evaluation and reporting of data quality in a standardized manner. Here, we describe each processing step in HAPPE, perform an example analysis with EEG files we have made freely available, and show that HAPPE outperforms seven alternative, widely-used processing approaches. HAPPE removes more artifact than all alternative approaches while simultaneously preserving greater or equivalent amounts of EEG signal in almost all instances. We also provide distributions of HAPPE's data quality metrics in an 867 file dataset as a reference distribution and in support of HAPPE's performance across EEG data with variable artifact

How historical copper contamination affects soil structure and mobilization and transport of colloids

DEFF Research Database (Denmark)

Paradelo, Marcos; Møldrup, Per; Holmstrup, Martin

between 0.01 to 0.43 pore volumes, with longer times for the most contaminated point, likely related with its higher soil density and lower air permeability. The copper pollution affected colloid and tracer transport in the soil columns. The release of colloids especially in the most contaminated points...

Postmortem validation of breast density using dual-energy mammography

Energy Technology Data Exchange (ETDEWEB)

Molloi, Sabee, E-mail: symolloi@uci.edu; Ducote, Justin L.; Ding, Huanjun; Feig, Stephen A. [Department of Radiological Sciences, University of California, Irvine, California 92697 (United States)

2014-08-15

Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dual energy mammography system. Glandular and adipose equivalent phantoms of uniform thickness were used to calibrate a dual energy basis decomposition algorithm. Dual energy decomposition was applied after scatter correction to calculate breast density. Breast density was also estimated using radiologist reader assessment, standard histogram thresholding and a fuzzy C-mean algorithm. Chemical analysis was used as the reference standard to assess the accuracy of different techniques to measure breast composition. Results: Breast density measurements using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean algorithm, and dual energy were in good agreement with the measured fibroglandular volume fraction using chemical analysis. The standard error estimates using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean, and dual energy were 9.9%, 8.6%, 7.2%, and 4.7%, respectively. Conclusions: The results indicate that dual energy mammography can be used to accurately measure breast density. The variability in breast density estimation using dual energy mammography was lower than reader assessment rankings, standard histogram thresholding, and fuzzy C-mean algorithm. Improved quantification of breast density is expected to further enhance its utility as a risk factor for breast cancer.

Postmortem validation of breast density using dual-energy mammography

International Nuclear Information System (INIS)

Molloi, Sabee; Ducote, Justin L.; Ding, Huanjun; Feig, Stephen A.

2014-01-01

Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dual energy mammography system. Glandular and adipose equivalent phantoms of uniform thickness were used to calibrate a dual energy basis decomposition algorithm. Dual energy decomposition was applied after scatter correction to calculate breast density. Breast density was also estimated using radiologist reader assessment, standard histogram thresholding and a fuzzy C-mean algorithm. Chemical analysis was used as the reference standard to assess the accuracy of different techniques to measure breast composition. Results: Breast density measurements using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean algorithm, and dual energy were in good agreement with the measured fibroglandular volume fraction using chemical analysis. The standard error estimates using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean, and dual energy were 9.9%, 8.6%, 7.2%, and 4.7%, respectively. Conclusions: The results indicate that dual energy mammography can be used to accurately measure breast density. The variability in breast density estimation using dual energy mammography was lower than reader assessment rankings, standard histogram thresholding, and fuzzy C-mean algorithm. Improved quantification of breast density is expected to further enhance its utility as a risk factor for breast cancer

Spin-adapted open-shell time-dependent density functional theory. II. Theory and pilot application.

Science.gov (United States)

Li, Zhendong; Liu, Wenjian; Zhang, Yong; Suo, Bingbing

2011-04-07

The excited states of open-shell systems calculated by unrestricted Kohn-Sham-based time-dependent density functional theory (U-TD-DFT) are often heavily spin-contaminated and hence meaningless. This is solved ultimately by the recently proposed spin-adapted time-dependent density functional theory (TD-DFT) (S-TD-DFT) [J. Chem. Phys. 133, 064106 (2010)]. Unlike the standard restricted open-shell Kohn-Sham-based TD-DFT (R-TD-DFT) which can only access the singlet-coupled single excitations, the S-TD-DFT can capture both the singlet- and triplet-coupled single excitations with the same computational effort as the U-TD-DFT. The performances of the three approaches (U-TD-DFT, R-TD-DFT, and S-TD-DFT) are compared for both the spin-conserving and spin-flip excitations of prototypical open-shell systems, the nitrogen (N(2)(+)) and naphthalene (C(10)H(8)(+)) cations. The results show that the S-TD-DFT gives rise to balanced descriptions of excited states of open-shell systems.

The European standard on planetary protection requirements.

Science.gov (United States)

Debus, André

2006-01-01

Since the beginning of solar system exploration, numerous spacecrafts have been sent towards others worlds, and one of the main goals of such missions is the search for extraterrestrial forms of life. It is known that, under certain conditions, some terrestrial entities are able to survive during cruises in space and that they may contaminate other planets (forward contamination). At another level, possible extraterrestrial life forms are unknown and their ability to contaminate the Earth's biosphere (back contamination) in the frame of sample return missions cannot be excluded. Article IX of the Outer Space Treaty (London/Washington, January 27, 1967) requires the preservation of planets and the Earth from contamination. All nations taking part in this Treaty must prevent forward and back contamination during missions exploring our solar system. Consequently, the United Nations (UN-COPUOS) has delegated COSPAR (Committee of Space Research) to take charge of planetary protection and, at present, all space-faring nations must comply with COSPAR policy and consequently with COSPAR planetary protection recommendations. Starting from these recommendations and the "CNES Planetary Protection Standard" document, a working group has been set up in the framework of the "European Cooperation for Space Standardization" (ECSS) to establish the main specifications for preventing cross-contamination between target bodies within the solar system and the Earth-moon system.

Rooftop runoff as a source of contamination: a review.

Science.gov (United States)

Lye, Dennis J

2009-10-15

Scientific reports concerning chemical and microbiological contaminant levels of rainwater runoff from rooftop collection in both urban and rural areas are reviewed. This alternative source of water has been documented to often contain substantial amounts of contaminants. Studies describing levels of heavy metal contamination specific to runoff from rooftop catchment areas containing exposed metal surfaces are discussed. Depending upon the intended use, scientific evidence is also accumulating that various treatments and disinfections will be required prior to release of roof-runoff water either into surface waters or for more direct consumer usage. For microbial contamination, current proposed standards and guidelines regarding this type of water source are shown to vary widely worldwide. Scientific literature reveals a lack of clarity regarding water quality guidelines and health related standards for certain types of rooftop runoff. Studies suggests that rainwater collection systems which are properly designed, maintained, and treated may provide a valuable supplement to existing water supplies by reducing demand on community water supplies/infrastructure costs, enhancing effective management of storm water runoff, and increasing restoration of underground reservoirs through controlled infiltration.

Radiation. Basics, influences, contamination situation, and countermeasures

International Nuclear Information System (INIS)

Baba, Mamoru; Nomura, Kiyoshi

2012-01-01

Fukushima Daiichi Nuclear Accident resulted in the contamination of a large area, and by now the situation of contamination and exposure has gradually clarified, and a lot of information has been being accumulated. Toward reconstruction of Fukushima prefecture from the current circumstance that the residents still live under continuing fear, this article discusses how to clarify the current situation and deal with the contamination, which the residents are concerned about. First, radiation, basic properties of radiation, and so on are introduced. Regarding the influence on human bodies, the mechanism and the degree of influence by radiation, especially on children, women, and pregnant women are explained. Next, regarding the measurements of radiation and radioactivity, the properties of measurement methods and the detectors are explained. Regarding the current situation of contamination and exposure, mainly addressing the area around Koriyama city, various topics are covered including: (1) situation of contamination and radiation monitoring, (2) countermeasures for radioactivity contamination, (3) internal exposure dose, (4) exposed dose from water and food, as well as (5) safety standards. (S.K.)

Relationship of Physical Parameters in Pb-Contaminated by Stabilization/Solidification Method

Directory of Open Access Journals (Sweden)

Ahmad Tajudin Saiful Azhar

2016-01-01

Full Text Available This research was performed to investigate the relationship between compressive strength, density and water absorption of Pb-contaminated soil treated by Ordinary Portland cement (OPC incorporated with sugarcane bagasse (SCB using the Stablisation/Solidification (S/S method. The SCB and OPC varying from 5% to 15% was added to stabilize and solidify the Pb-contaminated soil. The cylindrical samples were prepared and cured at room temperature for 28 days. Unconfined compression test, density test and water absorption test were conducted on these samples. The relationship between these variables were determined using simple statistical method by Analysis of Variance (ANOVA. Results indicate that there is a strong relationship between compressive strength and density with a regression coefficient of 77.4%. There is also a significant relationship between density and water absorption of approximately 70.7%. In addition, compressive strength and water absorption produced a strong relationship which is 73.6% of variability in strength development. In a nutshell, the strong relationship between these three variables represent the actual physical characteristics in S/S application.

Sequestration Coating Performance Requirements for Mitigation of Contamination from a Radiological Dispersion Device

International Nuclear Information System (INIS)

Drake, J.

2009-01-01

Immediate action would be necessary to minimize the effects of a radiological 'dirty bomb' detonation in a major city. After a dirty bomb has been detonated, vehicular and pedestrian traffic, as well as weather effects, would increase the spread of loose contamination, making control and recovery more difficult and costly. While contaminant migration and chemical binding into surface materials can be relatively rapid, the immediate treatment of surfaces with large quantities of an appropriate compound could alleviate much of the difficulty in decontamination. The EPA's National Homeland Security Research Center (NHSRC), in collaboration with ASTM International, is currently developing performance standards for materials which could be applied to exterior surfaces contaminated by an RDD to mitigate the spread and migration of radioactive contamination. These performance standards are being promulgated via an ASTM Standard Specification to be published by ASTM International. Test methods will be developed to determine if candidate coatings meet the performance requirements stipulated in the ASTM performance standard. These test methods will be adapted from existing standard methods, or will be devised through laboratory research. The final set of test methods will be codified in an ASTM or other standard test method. The principal market for products described in the ASTM performance standard would be federal, state and local government emergency responders and response planners, decontamination service providers and those whose interests include protection and recovery of real estate potentially at risk from radiological terrorism. (authors)

Radioactive contamination in monitors received for calibration

International Nuclear Information System (INIS)

Dias, Paulo S.; Santos, Gilvan C. dos; Brunelo, Maria Antonieta G.; Paula, Tiago C. de; Pires, Marina A.; Borges, Jose C.

2013-01-01

The Calibration Laboratory - LABCAL, from the Research Center for Metrology and Testing - METROBRAS, MRA Comercio de Instrumentos Eletronicos Ltda., began activities in October 2008 and, in August 2009, decided to establish a procedure for monitoring tests, external and internal, of all packages received from customers, containing instruments for calibration. The aim was to investigate possible contamination radioactive on these instruments. On July 2011, this procedure was extended to packagings of personal thermoluminescent dosemeters - TLD, received by the newly created Laboratory Laboratorio de Dosimetria Pessoal - LDP . In the monitoring procedure were used monitors with external probe, type pancake, MRA brand, models GP - 500 and MIR 7028. During the 37 months in which this investigation was conducted, were detected 42 cases of radioactive contamination, with the following characteristics: 1) just one case was personal dosimeter, TLD type; 2) just one case was not from a packing from nuclear medicine service - was from a mining company; 3) contamination occurred on packs and instruments, located and/or widespread; 4) contamination values ranged from slightly above the level of background radiation to about a thousand fold. Although METROBRAS has facilities for decontamination, in most cases, especially those of higher contamination, the procedure followed was to store the contaminated material in a room used for storage of radioactive sources. Periodically, each package and/or instrument was monitored, being released when the radiation level matched the background radiation. Every contamination detected, the client and/or owner of the instrument was informed. The Brazilian National Energy Commission - CNEN, was informed, during your public consultation for reviewing the standard for nuclear medicine services, held in mid-2012, having received from METROBRAS the statistical data available at the time. The high frequency of contamination detected and the high

Effects of combined sewer overflow and stormwater on indicator bacteria concentrations in the Tama River due to the high population density of Tokyo Metropolitan area.

Science.gov (United States)

Ham, Young-Sik; Kobori, Hiromi; Takasago, Masahisa

2009-05-01

The indicator bacteria (standard plate count, total coliform, and fecal coliform bacteria) concentrations have been investigated using six ambient habitats (population density, percent sewer penetration, stream flow rate (m(3)/sec), percent residential area, percent forest area and percent agricultural area) in the Tama River basin in Tokyo, Japan during June 2003 to January 2005. The downstream and tributary Tama River showed higher concentrations of TC and FC bacteria than the upstream waters, which exceeded an environmental quality standard for rivers and a bathing water quality criterion. It was estimated that combined sewer overflow (CSO) and stormwater effluents contributed -4-23% to the indicator bacteria concentrations of the Tama River. The results of multiple regression analyses show that the indicator bacteria concentrations of Tama River basin are significantly affected by population density. It is concluded that the Tama River received a significant bacterial contamination load originating from the anthropogenic source.

Evaluation of decontamination during dismantling of plutonium-contaminated glove boxes

International Nuclear Information System (INIS)

Kinugasa, Manabu; Taguchi, Seigi; Ohzeki, Satoru; Inoue, Yoshiaki; Kashima, Sadamitsu

1981-01-01

The dismantling work of plutonium-contaminated glove boxes was carried out. These glove boxes had been used for the R and D of plutonium-uranium mixed oxide fuel for 15 years. The work was carried out in a pressure-controlled greenhouse, and the contamination of air in the greenhouse was monitored continuously. In order to reduce the contamination of air during dismantling, the decontamination and fixation of loose contaminants on the surfaces of glove boxes were very important. The correlation between decontamination and the contamination of air regarding dismantling is reported in this paper. The surface contamination density of the glove boxes was measured utilizing the smear method before and after the decontamination, and the decontamination effects were estimated. The contamination of air during dismantling was continuously measured with a plutonium dust monitor. It was found that loose contamination exponentially decreased by the decontamination process. When the so-called wet glove boxes, which contained wet recovery and waste disposal apparatus, were dismantled, the contamination of air did not exceed 500 (MPC) a. However, the contamination of air exceeded 500 (MPC) a several times in the present work of dismantling the so-called dry glove boxes which had been used for the fabrication of plutonium-uranium mixed oxide pellets. (Kato, T.)

Transfer standard for the spectral density of relative intensity noise of optical fiber sources near 1550 nm

International Nuclear Information System (INIS)

Obarski, Gregory E.; Splett, Jolene D.

2001-01-01

We have developed a transfer standard for the spectral density of relative intensity noise (RIN) of optical fiber sources near 1550 nm. Amplified spontaneous emission (ASE) from an erbium-doped fiber amplifier (EDFA), when it is optically filtered over a narrow band (<5 nm), yields a stable RIN spectrum that is practically constant to several tens of gigahertz. The RIN is calculated from the power spectral density as measured with a calibrated optical spectrum analyzer. For a typical device it is -110 dB/Hz, with uncertainty ≤0.12 dB/Hz. The invariance of the RIN under attenuation yields a considerable dynamic range with respect to rf noise levels. Results are compared with those from a second method that uses a distributed-feedback laser (DFB) that has a Poisson-limited RIN. Application of each method to the same RIN measurement system yields frequency-dependent calibration functions that, when they are averaged, differ by ≤0.2 dB. [copyright] 2001 Optical Society of America

Cleaning, disinfection and sterilization of surface prion contamination.

Science.gov (United States)

McDonnell, G; Dehen, C; Perrin, A; Thomas, V; Igel-Egalon, A; Burke, P A; Deslys, J P; Comoy, E

2013-12-01

Prion contamination is a risk during device reprocessing, being difficult to remove and inactivate. Little is known of the combined effects of cleaning, disinfection and sterilization during a typical reprocessing cycle in clinical practice. To investigate the combination of cleaning, disinfection and/or sterilization on reducing the risk of surface prion contamination. In vivo test methods were used to study the impact of cleaning alone and cleaning combined with thermal disinfection and high- or low-temperature sterilization processes. A standardized test method, based on contamination of stainless steel wires with high titres of scrapie-infected brain homogenates, was used to determine infectivity reduction. Traditional chemical methods of surface decontamination against prions were confirmed to be effective, but extended steam sterilization was more variable. Steam sterilization alone reduced the risk of prion contamination under normal or extended exposure conditions, but did show significant variation. Thermal disinfection had no impact in these studies. Cleaning with certain defined formulations in combination with steam sterilization can be an effective prion decontamination process, in particular with alkaline formulations. Low-temperature, gaseous hydrogen peroxide sterilization was also confirmed to reduce infectivity in the presence and absence of cleaning. Prion decontamination is affected by the full reprocessing cycle used on contaminated surfaces. The correct use of defined cleaning, disinfection and sterilization methods as tested in this report in the scrapie infectivity assay can provide a standard precaution against prion contamination. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Reduction in Blood Culture Contamination Through Use of Initial Specimen Diversion Device.

Science.gov (United States)

Rupp, Mark E; Cavalieri, R Jennifer; Marolf, Cole; Lyden, Elizabeth

2017-07-15

Blood culture contamination is a clinically significant problem that results in patient harm and excess cost. In a prospective, controlled trial at an academic center Emergency Department, a device that diverts and sequesters the initial 1.5-2 mL portion of blood (which presumably carries contaminating skin cells and microbes) was tested against standard phlebotomy procedures in patients requiring blood cultures due to clinical suspicion of serious infection. In sum, 971 subjects granted informed consent and were enrolled resulting in 904 nonduplicative subjects with 1808 blood cultures. Blood culture contamination was significantly reduced through use of the initial specimen diversion device™ (ISDD) compared to standard procedure: (2/904 [0.22%] ISDD vs 16/904 [1.78%] standard practice, P = .001). Sensitivity was not compromised: true bacteremia was noted in 65/904 (7.2%) ISDD vs 69/904 (7.6%) standard procedure, P = .41. No needlestick injuries or potential bloodborne pathogen exposures were reported. The monthly rate of blood culture contamination for all nurse-drawn and phlebotomist-drawn blood cultures was modeled using Poisson regression to compare the 12-month intervention period to the 6 month before and after periods. Phlebotomists (used the ISDD) experienced a significant decrease in blood culture contamination while the nurses (did not use the ISDD) did not. In sum, 73% of phlebotomists completed a post-study anonymous survey and widespread user satisfaction was noted. Use of the ISDD was associated with a significant decrease in blood culture contamination in patients undergoing blood cultures in an Emergency Department setting. NCT02102087. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

Heavy metal accumulation in earthworms exposed to spatially variable soil contamination

NARCIS (Netherlands)

Marinussen, M.

1997-01-01

Ecotoxicity of contaminated soil is commonly tested in standard laboratory tests. Extrapolation of these data to the field scale is complicated due to considerable differences between conditions in laboratory tests and conditions in situ in contaminated soils. In this

Current Measures on Radioactive Contamination in Japan: A Policy Situation Analysis.

Science.gov (United States)

Gilmour, Stuart; Miyagawa, Shoji; Kasuga, Fumiko; Shibuya, Kenji

2016-01-01

The Great East Japan Earthquake on 11th March 2011 and the subsequent Fukushima Dai-ichi nuclear power plant disaster caused radioactive contamination in the surrounding environment. In the immediate aftermath of the accident the Government of Japan placed strict measures on radio-contamination of food, and enhanced radio-contamination monitoring activities. Japan is a pilot country in the WHO Foodborne Disease Burden Epidemiology Reference Group (FERG), and through this initiative has an opportunity to report on policy affecting chemicals and toxins in the food distribution network. Nuclear accidents are extremely rare, and a policy situation analysis of the Japanese government's response to the Fukushima Dai-ichi nuclear accident is a responsibility of Japanese scientists. This study aims to assess Japan government policies to reduce radio-contamination risk and to identify strategies to strengthen food policies to ensure the best possible response to possible future radiation accidents. We conducted a hand search of all publicly available policy documents issued by the Cabinet Office, the Food Safety Commission, the Ministry of Health, Labor and Welfare (MHLW), the Ministry of Agriculture, Forestry and Fishery (MAFF) and prefectural governments concerning food safety standards and changes to radiation and contamination standards since March 11th, 2011. We extracted information on food shipment and sales restrictions, allowable radio-contamination limits, monitoring activities and monitoring results. The standard for allowable radioactive cesium (Cs-134 and Cs-137) of 100 Bq/Kg in general food, 50 Bq/Kg in infant formula and all milk products, and 10 Bq/Kg in drinking water was enforced from April 2012 under the Food Sanitation Law, although a provisional standard on radio-contamination had been applied since the nuclear accident. Restrictions on the commercial sale and distribution of specific meat, vegetable and fish products were released for areas at risk of

Associative diazotrophic bacteria in grass roots and soils from heavy metal contaminated sites.

Science.gov (United States)

Moreira, Fátima M S; Lange, Anderson; Klauberg-Filho, Osmar; Siqueira, José O; Nóbrega, Rafaela S A; Lima, Adriana S

2008-12-01

This work aimed to evaluate density of associative diazotrophic bacteria populations in soil and grass root samples from heavy metal contaminated sites, and to characterize isolates from these populations, both, phenotypically (Zinc, Cadmium and NaCl tolerance in vitro, and protein profiles) and genotypically (16S rDNA sequencing), as compared to type strains of known diazotrophic species. Densities were evaluated by using NFb, Fam and JNFb media, commonly used for enrichment cultures of diazotrophic bacteria. Bacterial densities found in soil and grass root samples from contaminated sites were similar to those reported for agricultural soils. Azospirillum spp. isolates from contaminated sites and type strains from non-contaminated sites varied substantially in their in vitro tolerance to Zn+2 and Cd+2, being Cd+2 more toxic than Zn+2. Among the most tolerant isolates (UFLA 1S, 1R, S181, S34 and S22), some (1R, S34 and S22) were more tolerant to heavy metals than rhizobia from tropical and temperate soils. The majority of the isolates tolerant to heavy metals were also tolerant to salt stress as indicated by their ability to grow in solid medium supplemented with 30 g L(-1) NaCl. Five isolates exhibited high dissimilarity in protein profiles, and the 16S rDNA sequence analysis of two of them revealed new sequences for Azospirillum.

Effectiveness of a Novel Specimen Collection System in Reducing Blood Culture Contamination Rates.

Science.gov (United States)

Bell, Mary; Bogar, Catherine; Plante, Jessica; Rasmussen, Kristen; Winters, Sharon

2018-04-20

False-positive blood-culture results due to skin contamination of samples remain a persistent problem for health care providers. Our health system recognized that our rates of contamination across the 4 emergency department campuses were above the national average. A unique specimen collection system was implemented throughout the 4 emergency departments and became the mandatory way to collect adult blood cultures. The microbiology laboratory reported contamination rates weekly to manage potential problems; 7 months of data are presented here. There was an 82.8% reduction in false positives with the unique specimen collection system compared with the standard method (chi-squared test with Yates correction, 2-tailed, P = 0.0001). Based on the historical 3.52% rate of blood-culture contamination for our health facilities, 2.92 false positives were prevented for every 100 blood cultures drawn, resulting from adoption of the unique specimen collection system as the standard of care. This unique collection system can reduce the risk of blood culture contamination significantly and is designed to augment, rather than replace, the standard phlebotomy protocol already in use in most health care settings. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of past copper contamination and soil structure on copper leaching from soil

DEFF Research Database (Denmark)

Paradelo, M; Møldrup, Per; Arthur, Emmanuel

2013-01-01

Copper contamination affects biological, chemical, and physical soil properties and associated ecological functions. Changes in soil pore organization as a result of Cu contamination can dramatically affect flow and contaminant transport in polluted soils. This study assessed the influence of soil...... structure on the movement of water and Cu in a long-term polluted soil. Undisturbed soil cores collected along a Cu gradient (from about 20 to about 3800 mg Cu kg−1 soil) were scanned using X-ray computed tomography (CT). Leaching experiments were performed to analyze tracer transport, colloid leaching......, and dissolved organic carbon (DOC) and Cu losses. The 5% arrival time (t0.05) and apparent dispersivity (λapp) for tracer breakthrough were calculated by fitting the experimental data to a nonparametric, double-lognormal probability density function. Soil bulk density, which did not follow the Cu gradient...

Effects of microelements on soil nematode assemblages seven years after contaminating an agricultural field

NARCIS (Netherlands)

Nagy, P.; Bakonyi, G.; Bongers, A.M.T.; Kádár, I.; Fábián, M.; Kiss, I.

2004-01-01

Long-term effects of Cd, Cr, Cu, Se and Zn were studied 7 years after artificially contaminating plots of an agricultural field on a calcareous chernozem soil. Effects of three to four different contamination levels (originally 10, 30, 90 and 270 mg kg(-1)) were studied. Nematode density was

Comparing statistical tests for detecting soil contamination greater than background

International Nuclear Information System (INIS)

Hardin, J.W.; Gilbert, R.O.

1993-12-01

The Washington State Department of Ecology (WSDE) recently issued a report that provides guidance on statistical issues regarding investigation and cleanup of soil and groundwater contamination under the Model Toxics Control Act Cleanup Regulation. Included in the report are procedures for determining a background-based cleanup standard and for conducting a 3-step statistical test procedure to decide if a site is contaminated greater than the background standard. The guidance specifies that the State test should only be used if the background and site data are lognormally distributed. The guidance in WSDE allows for using alternative tests on a site-specific basis if prior approval is obtained from WSDE. This report presents the results of a Monte Carlo computer simulation study conducted to evaluate the performance of the State test and several alternative tests for various contamination scenarios (background and site data distributions). The primary test performance criteria are (1) the probability the test will indicate that a contaminated site is indeed contaminated, and (2) the probability that the test will indicate an uncontaminated site is contaminated. The simulation study was conducted assuming the background concentrations were from lognormal or Weibull distributions. The site data were drawn from distributions selected to represent various contamination scenarios. The statistical tests studied are the State test, t test, Satterthwaite's t test, five distribution-free tests, and several tandem tests (wherein two or more tests are conducted using the same data set)

ISO radiation protection standards

International Nuclear Information System (INIS)

Becker, K.; West, N.

1981-01-01

After a brief description of the International Organization for Standardization (ISO) and its Technical Committee (TC) 85 ''Nuclear Energy'', the work of its Sub-Committee (SC) 2 ''Radiation Protection'' is described in some detail. Several international standards on subjects closely related to radiation protection have already been published, for example ISO-361 (Basic radiation protection symbol), ISO-1757 (Photographic dosimeters), ISO-1758 and 1759 (Direct and indirect-reading pocket exposure meters), ISO-2889 (Sampling of airborne radioactive materials), ISO-4037 (X and gamma reference radiations for calibration) and ISO-4071 (Testing of exposure meters and dosimeters). TC 85/SC 2 has currently eight active Working Groups (WG) dealing with 14 standards projects, mostly in advanced stages, in such fields as neutron and beta reference radiations, and X and gamma radiations of high and low dose-rates and high energies for calibration purposes, reference radiations for surface contamination apparatus, ejection systems for gamma radiography apparatus, industrial and laboratory irradiators, lead shielding units, protective clothing, thermoluminescence dosemeters, radioelement gauges, and surface contamination and decontamination. (author)

Density meters utilizing ionizing radiation: definitions and test methods

International Nuclear Information System (INIS)

Anon.

1981-01-01

This standard is applicable to density meters utilizing ionizing radiation, designed for the measurement of the density of liquids, slurries or fluidized solids. The standard applies to transmission-type instruments only. Reference to compliance with this standard shall identify any deviations and the reasons for such deviations. Safety aspects are not included but should fulfill the requirements of all relevant internationally accepted standards

Density-density functionals and effective potentials in many-body electronic structure calculations

International Nuclear Information System (INIS)

Reboredo, Fernando A.; Kent, Paul R.

2008-01-01

We demonstrate the existence of different density-density functionals designed to retain selected properties of the many-body ground state in a non-interacting solution starting from the standard density functional theory ground state. We focus on diffusion quantum Monte Carlo applications that require trial wave functions with optimal Fermion nodes. The theory is extensible and can be used to understand current practices in several electronic structure methods within a generalized density functional framework. The theory justifies and stimulates the search of optimal empirical density functionals and effective potentials for accurate calculations of the properties of real materials, but also cautions on the limits of their applicability. The concepts are tested and validated with a near-analytic model.

Contamination of dried blood spots - an underestimated risk in newborn screening.

Science.gov (United States)

Winter, Theresa; Lange, Anja; Hannemann, Anke; Nauck, Matthias; Müller, Cornelia

2018-01-26

Newborn screening (NBS) is an established screening procedure in many countries worldwide, aiming at the early detection of inborn errors of metabolism. For decades, dried blood spots have been the standard specimen for NBS. The procedure of blood collection is well described and standardized and includes many critical pre-analytical steps. We examined the impact of contamination of some anticipated common substances on NBS results obtained from dry spot samples. This possible pre-analytical source of uncertainty has been poorly examined in the past. Capillary blood was obtained from 15 adult volunteers and applied to 10 screening filter papers per volunteer. Nine filter papers were contaminated without visible trace. The contaminants were baby diaper rash cream, baby wet wipes, disinfectant, liquid infant formula, liquid infant formula hypoallergenic (HA), ultrasonic gel, breast milk, feces, and urine. The differences between control and contaminated samples were evaluated for 45 NBS quantities. We estimated if the contaminations might lead to false-positive NBS results. Eight of nine investigated contaminants significantly altered NBS analyte concentrations and potentially caused false-positive screening outcomes. A contamination with feces was most influential, affecting 24 of 45 tested analytes followed by liquid infant formula (HA) and urine, affecting 19 and 13 of 45 analytes, respectively. A contamination of filter paper samples can have a substantial effect on the NBS results. Our results underline the importance of good pre-analytical training to make the staff aware of the threat and ensure reliable screening results.

Simulation–optimization model for groundwater contamination ...

Indian Academy of Sciences (India)

used techniques for groundwater remediation in which the contaminated groundwater is pumped ... ing the affected groundwater aquifer down to some drinking water standard. Several .... For simplicity, rectangular support domain is used in this study. Figure 1 ..... For PAT remediation system, decision variables include the.

Fungal contamination of produced wheat flour in West Azerbaijan, northwest of Iran

Directory of Open Access Journals (Sweden)

Jafar Asadzadeh

2014-09-01

Full Text Available Objective: To investigate fungal contamination of produced wheat flours in West Azarbaijan Province, located in the North West of Iran as wheat flour is one of the most important food and nutrient in the Iranians diet. Methods: This descriptive study was performed during March 2011 to April 2013 in flour mills of West Azerbaijan province. A total of 17 samples of produced wheat flour in Azerbaijan Province of Iran were tested for mold contamination based on Iran National Standard Method No. 2393. Results: Presence of molds in all collected 151 samples from flour factories of Azerbaijan Province were at the limit based on Iranian national standard. Conclusions: The obtained results showed that the process of flour production was hygienic quietly. Bread is staple ingredient of Iranian diet, and strict control on its processing of wheat flour, maintenance and distribution results nonpolluting or reduction of fungal contamination. Objective: To investigate fungal contamination of produced wheat flours in West Azarbaijan Province, located in the North West of Iran as wheat flour is one of the most important food and nutrient in the Iranians diet. Methods: This descriptive study was performed during March 2011 to April 2013 in flour mills of West Azerbaijan province. A total of 17 samples of produced wheat flour in Azerbaijan Province of Iran were tested for mold contamination based on Iran National Standard Method No. 2393. Results: Presence of molds in all collected 151 samples from flour factories of Azerbaijan Province were at the limit based on Iranian national standard. Conclusions: The obtained results showed that the process of flour production was hygienic quietly. Bread is staple ingredient of Iranian diet, and strict control on its processing of wheat flour, maintenance and distribution results nonpolluting or reduction of fungal contamination.

Measurement of residual radioactive surface contamination by 2-D laser heated TLD

International Nuclear Information System (INIS)

Jones, S.C.

1997-06-01

The feasibility of applying and adapting a two-dimensional laser heated thermoluminescence dosimetry system to the problem of surveying for radioactive surface contamination was studied. The system consists of a CO 2 laser-based reader and monolithic arrays of thin dosimeter elements. The arrays consist of 10,201 thermoluminescent phosphor elements of 40 micron thickness, covering a 900 cm 2 area. Array substrates are 125 micron thick polyimide sheets, enabling them to easily conform to regular surface shapes, especially for survey of surfaces that are inaccessible for standard survey instruments. The passive, integrating radiation detectors are sensitive to alpha and beta radiation at contamination levels below release guideline limits. Required contact times with potentially contaminated surfaces are under one hour to achieve detection of transuranic alpha emission at 100 dpm/100 cm 2 . Positional information obtained from array evaluation is useful for locating contamination zones. Unique capabilities of this system for survey of sites, facilities and material include measurement inside pipes and other geometrical configurations that prevent standard surveys, and below-surface measurement of alpha and beta emitters in contaminated soils. These applications imply a reduction of material that must be classified as radioactive waste by virtue of its possibility of contamination, and cost savings in soil sampling at contaminated sites

Contaminant analysis automation, an overview

International Nuclear Information System (INIS)

Hollen, R.; Ramos, O. Jr.

1996-01-01

To meet the environmental restoration and waste minimization goals of government and industry, several government laboratories, universities, and private companies have formed the Contaminant Analysis Automation (CAA) team. The goal of this consortium is to design and fabricate robotics systems that standardize and automate the hardware and software of the most common environmental chemical methods. In essence, the CAA team takes conventional, regulatory- approved (EPA Methods) chemical analysis processes and automates them. The automation consists of standard laboratory modules (SLMs) that perform the work in a much more efficient, accurate, and cost- effective manner

Toxicological benchmarks for screening potential contaminants of concern for effects on terrestrial plants

International Nuclear Information System (INIS)

Suter, G.W. II; Will, M.E.; Evans, C.

1993-09-01

One of the initial stages in ecological risk assessment for hazardous waste sites is the screening of contaminants to determine which of them are worthy of further consideration as ''contaminants of potential concern.'' This process is termed ''contaminant screening.'' It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 34 chemicals potentially associated with US Department of Energy (DOE) sites. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern. The purpose of this report is to present plant toxicity data and discuss their utility as benchmarks for determining the hazard to terrestrial plants caused by contaminants in soil. Benchmarks are provided for soils and solutions

[Legionella spp. contamination in indoor air: preliminary results of an Italian multicenter study].

Science.gov (United States)

Montagna, Maria Teresa; De Giglio, Osvalda; Napoli, Christian; Cannova, Lucia; Cristina, Maria Luisa; Deriu, Maria Grazia; Delia, Santi Antonino; Giuliano, Ada; Guida, Marco; Laganà, Pasqualina; Liguori, Giorgio; Mura, Ida; Pennino, Francesca; Rossini, Angelo; Tardivo, Stefano; Torre, Ida; Torregrossa, Maria Valeria; Villafrate, Maria Rosaria; Albertini, Roberto; Pasquarella, Cesira

2014-01-01

To propose a standardized protocol for the evaluation of Legionella contamination in air. A bathroom having a Legionella contamination in water >1,000 cfu/l was selected in 10 different healthcare facilities. Air contamination was assessed by active (Surface Air System, SAS) and passive (Index of Microbial Air, IMA) sampling for 8 hours, about 1 m away from the floor and 50 cm from the tap water. Two hundred liters of air were sampled by SAS every 12 min, after flushing water for 2 min. The IMA value was calculated as the mean value of colony forming units/16 plates exposed during sampling (2 plates/hour). Water contamination was evaluated at T0, after 4 and 8 hours, according to the standard methods. Air contamination by Legionella was found in three healthcare facilities (one with active and two with passive sampling), showing a concomitant tap water contamination (median=40,000; range 1,100-43,000 cfu/l). The remaining seven hospitals isolated Legionella spp. exclusively from water samples (median=8,000; range 1,200-70,000 cfu/l). Our data suggest that environmental Legionella contamination cannot be assessed only through the air sampling, even in the presence of an important water contamination.

Protein concentrate production from the biomass contaminated with radionuclides

International Nuclear Information System (INIS)

Nizhko, V.F.; Shinkarenko, M.P.; Polozhaj, V.V.; Krivchik, O.V.

1992-01-01

Coefficients of radionuclides accumulation are determined for traditional and rare forage crops grown on contaminated soils. It is shown that with low concentration of radionuclides in soil minimal level of contamination were found in the biomass of lupine (Lupinus luteus L.) and sainfoin (Onobrychis hybridus L.). Relatively high levels of contamination were found in comfrey (Symphytum asperum Lepech.) and bistort (Polygonum divaricatum L.). Comparatively low accumulation coefficients in case of higher density of soil contamination were observed for white and yellow sweetclovers (Melilotus albus Medik. and M. officinalis (L.) Desr.), while higher values of coefficients were found for bird's-foot trefoil (Lotus corniculatus L.), white clover (Trifolium repens L.) and alsike clover (t. hybridum L.). Biomass of white sweet-clover and alsike clover has been processed to produce leaf protein concentrate. It is shown that with biomass contamination of 1 kBq/kg and above conventional technology based on thermal precipitation of the protein does not provide production of pure product. More purified protein concentrates are obtained after two-stage processing of the biomass

DFT Study On Effects of CO2 Contamination in Non-Aqueous Li-Air Batteries

DEFF Research Database (Denmark)

Mekonnen, Yedilfana Setarge; Mýrdal, Jón Steinar Garðarsson; Vegge, Tejs

2013-01-01

Density Functional Theory (DFT) studies on the effects of carbon dioxide (CO2) contamination at the cathode of rechargeable non-aqueous Li-O2 batteries, where the insulating material Lithium peroxide (Li2O2) is the main discharge product. The Li2O2 growth mechanism and overpotentials are investig...... and result in an increased battery capacity. However, CO2 contamination on the Li2O2 surface confirms an asymmetric increase in the overpotentials; particularly the charging overvoltage exhibits sustantial increase, which would reduce the efficiency of the Li-air battery.......Density Functional Theory (DFT) studies on the effects of carbon dioxide (CO2) contamination at the cathode of rechargeable non-aqueous Li-O2 batteries, where the insulating material Lithium peroxide (Li2O2) is the main discharge product. The Li2O2 growth mechanism and overpotentials...

Transfer standard for the spectral density of relative intensity noise of optical fiber sources near 1550 nm

Energy Technology Data Exchange (ETDEWEB)

Obarski, Gregory E.; Splett, Jolene D.

2001-06-01

We have developed a transfer standard for the spectral density of relative intensity noise (RIN) of optical fiber sources near 1550 nm. Amplified spontaneous emission (ASE) from an erbium-doped fiber amplifier (EDFA), when it is optically filtered over a narrow band ({lt}5 nm), yields a stable RIN spectrum that is practically constant to several tens of gigahertz. The RIN is calculated from the power spectral density as measured with a calibrated optical spectrum analyzer. For a typical device it is {minus}110 dB/Hz, with uncertainty {le}0.12 dB/Hz. The invariance of the RIN under attenuation yields a considerable dynamic range with respect to rf noise levels. Results are compared with those from a second method that uses a distributed-feedback laser (DFB) that has a Poisson-limited RIN. Application of each method to the same RIN measurement system yields frequency-dependent calibration functions that, when they are averaged, differ by {le}0.2 dB. {copyright} 2001 Optical Society of America

Risk Assessment Approaches for Carcinogenic Food Contaminants

OpenAIRE

Gillespie, Zoe; Pulido, Olga; Vavasour, Elizabeth

2011-01-01

Health Canada has identified the need for a standardized department-wide approach for the risk assessment of carcinogens in foods (e.g., pesticides, food chemical contaminants, veterinary therapeutics). A standardized approach would better facilitate and inform risk management strategies for the control of human exposure to food sources of carcinogens. Within the post- market regulatory context, directly DNA-reactive carcinogens are of most concern because any exposure is theoretically assume...

49 CFR 192.381 - Service lines: Excess flow valve performance standards.

Science.gov (United States)

2010-10-01

... SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Customer... prior experience with contaminants in the gas stream, where these contaminants could be expected to...

[Regional features of food standards and health risks associated with chemical contamination of food].

Science.gov (United States)

Klepikov, O V; Khatuaev, R O; Istomin, A V; Rumyantseva, L A

In the article there are presented results of a study of the balance of food consumption by the population of the Voronezh region, the assessment of the level of contamination of food products and both carcinogenic and non-carcinogenic and public health risk caused by this contamination. There was evaluated the level of nutrition-dependent diseases. A special feature of this study is a comparative analysis of data obtained during the two five-year periods of 1995-1999 and 2010-2014, that permitted to reveal changes in food consumption, the dynamics of morbidity rate associated with the nutritional factor.

Newly developed standard reference materials for organic contaminant analysis

Energy Technology Data Exchange (ETDEWEB)

Poster, D.; Kucklick, J.; Schantz, M.; Porter, B.; Wise, S. [National Inst. of Stand. and Technol., Gaithersburg, MD (USA). Center for Anal. Chem.

2004-09-15

The National Institute of Standards and Technology (NIST) has issued a number of Standard Reference Materials (SRM) for specified analytes. The SRMs are biota and biological related materials, sediments and particle related SRMs. The certified compounds for analysis are polychlorinated biphenyls (PCB), polycylic aromatic hydrocarbons (PAH) and their nitro-analogues, chlorinated pesticides, methylmercury, organic tin compounds, fatty acids, polybrominated biphenyl ethers (PBDE). The authors report on origin of materials and analytic methods. (uke)

Natural uranium toxicology - evaluation of internal contamination in man; Toxicologie de l'uranium naturel - essai d'evaluation de la contamination interne chez l'homme

Energy Technology Data Exchange (ETDEWEB)

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

1968-07-01

After reminding the physical and chemical properties of natural uranium which might affect its toxicology, a comprehensive investigation upon natural uranium metabolism and toxicity and after applying occupational exposure standards to this particular poison, it has been determined, from accident reports and human experience reported in the related literature, a series of formulae obtained by theoretical mathematical development giving principles for internal contamination monitoring and disclosure by determining uranium in the urine of occupationally exposed individuals. An assay is performed to determine individual internal contamination according to the various contamination cases. The outlined purposes, mainly practical, required some options and extrapolations. The proposed formula allows a preliminary approach and also to determine shortly a contamination extent or to discuss the systematical urinalysis results as compared with individual radio-toxicology monitoring professional standards. (author) [French] Apres le rappel des caracteristiques physiques et des proprietes chimiques de l'uranium naturel pouvant avoir une influence sur sa toxicologie, l'etude detaillee de son metabolisme et de sa toxicite, puis l'application des normes professionnelles d'exposition au cas particulier de ce toxique, il est etabli, a partir des comptes rendus d'accidents et de l'experimentation humaine rapportes dans la litterature, une serie de formules obtenues par developpement mathematique theorique qui posent les principes de la surveillance et de la mise en evidence de la contamination interne par la recherche et le dosage de l'uranium dans les urines d'individus professionnellement exposes. Un essai d'evaluation de la contamination interne individuelle suivant les differents cas de contamination est effectue. Le formulaire propose permet de faire une premiere approximation et d'apprecier rapidement l'importance d'une contamination ou bien d'interpreter les resultats d

Structural-genetic approach to analysis and mapping of Chernobyl's radionuclide contamination field

International Nuclear Information System (INIS)

Proskura, N.I.; Bujkov, M.; Nagorsky, V.A.; Tepikin, V.; Poletaev, V.; Solyanke, E.G.; Shkvorets, O.Y.; Shestopalov, V.M.; Skvortsov, V.

1997-01-01

As a main tool for revealing and interpreting the internal structure of radionuclide contamination field, around the Chernobyl NPP the reliable and validated detailed scale maps of contamination densities could serve. Such maps should have, on the one hand, a high enough density of initial observation points (not less than 1 to 10 points per 1 sq.cm. of final map) and, on the other hand, a high representativeness of each observation point, i.e. reliability of presentation of its vicinity (0.1 to 1 sq.km). The available analytical data files of soil sampling in the exclusion zone conform neither to the first requirement, nor to the second one: real density of sampling does not exceed 0-2 to 0.5 points per 1 sq.m, and the representativeness of obtained results has a typical variation from medium values (in the neighbourhood of 0.1 to 1 sq.km) to 3 to 5 times

Bacterial contamination of traditional ice creams in Kermanshah in 2008

Directory of Open Access Journals (Sweden)

Sina Emami

2013-09-01

Full Text Available Background: Ice cream is a dairy product that is very popular during warm seasons. Ice cream can be contaminated with various microorganisms including pathogenic bacteria if hygienic procedures are not followed during preparation, distribution and preservation processes. This may put the health of people using ice cream at risk. Our study aimed to examine the bacterial contamination of traditional ice creams in Kermanshah city during 2008. Methods: During summer 2008, 80 samples of traditional ice creams were collected. The samples were examined according to the Iranian National Standard protocols for E. coli, Coliforms,  Salmonella,  Staphylococcus aureus and complete count of microorganisms. Results: Overall, 62 (77.5% samples had microbial contaminations more than the standard limit. Results showed 59 (73.75% and 54 (67.5 % of the samples contained a high number of microorganisms and coliform, respectively. Furthermore 30 (37.5% and 23 (28.75% of the samples were contaminated with E. coli and S. aureus, respectively. However, Salmonella spp. was not found in any of the ice cream samples. Conclusion: The traditional ice creams tested in Kermanshah were heavily contaminated with bacteria. It could be due to the inappropriate preparation and preservation procedures using unpasteurized milk and other materials.  Contaminations may also be induced by personals. So it is recommended to apply the hygienic procedures for preparation and preservation of ice cream including the use of pasteurized milk and other materials.

Current Measures on Radioactive Contamination in Japan: A Policy Situation Analysis.

Directory of Open Access Journals (Sweden)

Stuart Gilmour

Full Text Available The Great East Japan Earthquake on 11th March 2011 and the subsequent Fukushima Dai-ichi nuclear power plant disaster caused radioactive contamination in the surrounding environment. In the immediate aftermath of the accident the Government of Japan placed strict measures on radio-contamination of food, and enhanced radio-contamination monitoring activities. Japan is a pilot country in the WHO Foodborne Disease Burden Epidemiology Reference Group (FERG, and through this initiative has an opportunity to report on policy affecting chemicals and toxins in the food distribution network. Nuclear accidents are extremely rare, and a policy situation analysis of the Japanese government's response to the Fukushima Dai-ichi nuclear accident is a responsibility of Japanese scientists. This study aims to assess Japan government policies to reduce radio-contamination risk and to identify strategies to strengthen food policies to ensure the best possible response to possible future radiation accidents.We conducted a hand search of all publicly available policy documents issued by the Cabinet Office, the Food Safety Commission, the Ministry of Health, Labor and Welfare (MHLW, the Ministry of Agriculture, Forestry and Fishery (MAFF and prefectural governments concerning food safety standards and changes to radiation and contamination standards since March 11th, 2011. We extracted information on food shipment and sales restrictions, allowable radio-contamination limits, monitoring activities and monitoring results. The standard for allowable radioactive cesium (Cs-134 and Cs-137 of 100 Bq/Kg in general food, 50 Bq/Kg in infant formula and all milk products, and 10 Bq/Kg in drinking water was enforced from April 2012 under the Food Sanitation Law, although a provisional standard on radio-contamination had been applied since the nuclear accident. Restrictions on the commercial sale and distribution of specific meat, vegetable and fish products were released for

Polycyclic aromatic hydrocarbon contamination in stormwater detention pond sediments in coastal South Carolina.

Science.gov (United States)

Weinstein, John E; Crawford, Kevin D; Garner, Thomas R

2010-03-01

The purpose of this study was to characterize the polycyclic aromatic hydrocarbon (PAH) contamination in the sediments of stormwater detention ponds in coastal South Carolina. Levels of the sum of PAH analytes were significantly higher in the sediments of commercial ponds compared to that of reference, golf course, low-density residential, and high-density residential ponds. Isomer ratio analysis suggested that the predominant source of PAHs were pyrogenic; however, many ponds had a PAH signature consistent with mixed uncombusted and combusted PAH sources. PAH levels in these sediments could be modeled using both pond drainage area and pond surface area. These results demonstrate that the sediment from most commercial ponds, and a few residential and golf course ponds, were moderately contaminated with PAHs. PAH levels in these contaminated ponds exceeded between 42% and 75% of the ecological screening values for individual PAH analytes established by US EPA Region IV, suggesting that they may pose a toxicological risk to wildlife.

Density-functional theory for internal magnetic fields

Science.gov (United States)

Tellgren, Erik I.

2018-01-01

A density-functional theory is developed based on the Maxwell-Schrödinger equation with an internal magnetic field in addition to the external electromagnetic potentials. The basic variables of this theory are the electron density and the total magnetic field, which can equivalently be represented as a physical current density. Hence, the theory can be regarded as a physical current density-functional theory and an alternative to the paramagnetic current density-functional theory due to Vignale and Rasolt. The energy functional has strong enough convexity properties to allow a formulation that generalizes Lieb's convex analysis formulation of standard density-functional theory. Several variational principles as well as a Hohenberg-Kohn-like mapping between potentials and ground-state densities follow from the underlying convex structure. Moreover, the energy functional can be regarded as the result of a standard approximation technique (Moreau-Yosida regularization) applied to the conventional Schrödinger ground-state energy, which imposes limits on the maximum curvature of the energy (with respect to the magnetic field) and enables construction of a (Fréchet) differentiable universal density functional.

EG type radioactive calibration standards

International Nuclear Information System (INIS)

1980-01-01

EG standards are standards with a radioactive substance deposited as a solution on filtration paper and after drying sealed into a plastic disc or cylinder shaped casing. They serve the official testing of X-ray and gamma spectrometers and as test sources. The table shows the types of used radionuclides, nominal values of activity and total error of determination not exceeding +-4%. Activity of standards is calculated from the charge and the specific activity of standard solution used for the preparation of the standard. Tightness and surface contamination is measured for each standard. The manufacturer, UVVVR Praha, gives a guarantee for the given values of activity and total error of determination. (M.D.)

[Establishment of Assessment Method for Air Bacteria and Fungi Contamination].

Science.gov (United States)

Zhang, Hua-ling; Yao, Da-jun; Zhang, Yu; Fang, Zi-liang

2016-03-15

In this paper, in order to settle existing problems in the assessment of air bacteria and fungi contamination, the indoor and outdoor air bacteria and fungi filed concentrations by impact method and settlement method in existing documents were collected and analyzed, then the goodness of chi square was used to test whether these concentration data obeyed normal distribution at the significant level of α = 0.05, and combined with the 3σ principle of normal distribution and the current assessment standards, the suggested concentrations ranges of air microbial concentrations were determined. The research results could provide a reference for developing air bacteria and fungi contamination assessment standards in the future.

Radio-frequency slurry-density measurement for dredging pipelines

NARCIS (Netherlands)

van Eeten, M.J.C.

2011-01-01

Hydraulic dredgers make use of a density meter to measure the instantaneous density in the slurry transport pipeline, primarily for process control and production calculation. the current ‘golden’ standard for slurry density measurement is the radioactive density meter. It is based on a slurry

Standard Clock in primordial density perturbations and cosmic microwave background

International Nuclear Information System (INIS)

Chen, Xingang; Namjoo, Mohammad Hossein

2014-01-01

Standard Clocks in the primordial epoch leave a special type of features in the primordial perturbations, which can be used to directly measure the scale factor of the primordial universe as a function of time a(t), thus discriminating between inflation and alternatives. We have started to search for such signals in the Planck 2013 data using the key predictions of the Standard Clock. In this Letter, we summarize the key predictions of the Standard Clock and present an interesting candidate example in Planck 2013 data. Motivated by this candidate, we construct and compute full Standard Clock models and use the more complete prediction to make more extensive comparison with data. Although this candidate is not yet statistically significant, we use it to illustrate how Standard Clocks appear in Cosmic Microwave Background (CMB) and how they can be further tested by future data. We also use it to motivate more detailed theoretical model building

Smart density: A more accurate method of measuring rural residential density for health-related research.

Science.gov (United States)

Owens, Peter M; Titus-Ernstoff, Linda; Gibson, Lucinda; Beach, Michael L; Beauregard, Sandy; Dalton, Madeline A

2010-02-12

Studies involving the built environment have typically relied on US Census data to measure residential density. However, census geographic units are often unsuited to health-related research, especially in rural areas where development is clustered and discontinuous. We evaluated the accuracy of both standard census methods and alternative GIS-based methods to measure rural density. We compared residential density (units/acre) in 335 Vermont school neighborhoods using conventional census geographic units (tract, block group and block) with two GIS buffer measures: a 1-kilometer (km) circle around the school and a 1-km circle intersected with a 100-meter (m) road-network buffer. The accuracy of each method was validated against the actual residential density for each neighborhood based on the Vermont e911 database, which provides an exact geo-location for all residential structures in the state. Standard census measures underestimate residential density in rural areas. In addition, the degree of error is inconsistent so even the relative rank of neighborhood densities varies across census measures. Census measures explain only 61% to 66% of the variation in actual residential density. In contrast, GIS buffer measures explain approximately 90% of the variation. Combining a 1-km circle with a road-network buffer provides the closest approximation of actual residential density. Residential density based on census units can mask clusters of development in rural areas and distort associations between residential density and health-related behaviors and outcomes. GIS-defined buffers, including a 1-km circle and a road-network buffer, can be used in conjunction with census data to obtain a more accurate measure of residential density.

Smart density: a more accurate method of measuring rural residential density for health-related research

Directory of Open Access Journals (Sweden)

Gibson Lucinda

2010-02-01

Full Text Available Abstract Background Studies involving the built environment have typically relied on US Census data to measure residential density. However, census geographic units are often unsuited to health-related research, especially in rural areas where development is clustered and discontinuous. Objective We evaluated the accuracy of both standard census methods and alternative GIS-based methods to measure rural density. Methods We compared residential density (units/acre in 335 Vermont school neighborhoods using conventional census geographic units (tract, block group and block with two GIS buffer measures: a 1-kilometer (km circle around the school and a 1-km circle intersected with a 100-meter (m road-network buffer. The accuracy of each method was validated against the actual residential density for each neighborhood based on the Vermont e911 database, which provides an exact geo-location for all residential structures in the state. Results Standard census measures underestimate residential density in rural areas. In addition, the degree of error is inconsistent so even the relative rank of neighborhood densities varies across census measures. Census measures explain only 61% to 66% of the variation in actual residential density. In contrast, GIS buffer measures explain approximately 90% of the variation. Combining a 1-km circle with a road-network buffer provides the closest approximation of actual residential density. Conclusion Residential density based on census units can mask clusters of development in rural areas and distort associations between residential density and health-related behaviors and outcomes. GIS-defined buffers, including a 1-km circle and a road-network buffer, can be used in conjunction with census data to obtain a more accurate measure of residential density.

X-231B technology demonstration for in situ treatment of contaminated soil: Contaminant characterization and three dimensional spatial modeling

International Nuclear Information System (INIS)

West, O.R.; Siegrist, R.L.; Mitchell, T.J.; Pickering, D.A.; Muhr, C.A.; Greene, D.W.; Jenkins, R.A.

1993-11-01

Fine-textured soils and sediments contaminated by trichloroethylene (TCE) and other chlorinated organics present a serious environmental restoration challenge at US Department of Energy (DOE) sites. DOE and Martin Marietta Energy Systems, Inc. initiated a research and demonstration project at Oak Ridge National Laboratory. The goal of the project was to demonstrate a process for closure and environmental restoration of the X-231B Solid Waste Management Unit at the DOE Portsmouth Gaseous Diffusion Plant. The X-231B Unit was used from 1976 to 1983 as a land disposal site for waste oils and solvents. Silt and clay deposits beneath the unit were contaminated with volatile organic compounds and low levels of radioactive substances. The shallow groundwater was also contaminated, and some contaminants were at levels well above drinking water standards. This document begins with a summary of the subsurface physical and contaminant characteristics obtained from investigative studies conducted at the X-231B Unit prior to January 1992 (Sect. 2). This is then followed by a description of the sample collection and analysis methods used during the baseline sampling conducted in January 1992 (Sect. 3). The results of this sampling event were used to develop spatial models for VOC contaminant distribution within the X-231B Unit

Evaluation of microbial contamination of canine plasma eyedropper bottles following clinical use in canine patients.

Science.gov (United States)

Strauss, Rachel A; Genschel, Ulrike; Allbaugh, Rachel A; Sebbag, Lionel; Ben-Shlomo, Gil

2018-05-24

To investigate microbial contamination of canine plasma eye drops when used clinically and to compare the effect of two different eyedropper bottles on contamination rate. Forty-six bottles containing plasma were randomly dispensed for use on 42 dogs with ulcerative keratitis. Of these, 23 were standard eyedropper bottles and 23 were Novelia ® bottles designed to prevent contamination. After use for up to 2 weeks, samples for bacterial culture were obtained from a drop of plasma, the bottle tip, the plasma inside the bottle, and the corneal surface. Fungal culture was performed from a drop of plasma. The overall microbial contamination rate was 17.4% (8/46 bottles); however, only one bottle had growth from the plasma inside the bottle. There was a lower contamination rate of Novelia ® bottles (3/23 = 13.0%) compared to standard bottles (5/23 = 21.7%), but this difference was not statistically significant (P = .57). There were also no significant differences in contamination rate of bottles used greater than 7 days compared to less than or equal to 7 days, or in bottles used greater than 4 times daily compared to 4 times daily or less. Three corneal samples (6.5%) had bacterial growth, but none matched contamination from the bottles. Novelia ® bottles may decrease contamination of plasma eye drops used clinically. However, while microbial contamination of plasma bottles was documented, no clinically relevant complications were observed. This study supports safe use of plasma eye drops for up to 2 weeks when refrigerated and dispensed from either Novelia ® or standard eyedropper bottles. © 2018 American College of Veterinary Ophthalmologists.

Microplastic contamination of river beds significantly reduced by catchment-wide flooding

Science.gov (United States)

Hurley, Rachel; Woodward, Jamie; Rothwell, James J.

2018-04-01

Microplastic contamination of the oceans is one of the world's most pressing environmental concerns. The terrestrial component of the global microplastic budget is not well understood because sources, stores and fluxes are poorly quantified. We report catchment-wide patterns of microplastic contamination, classified by type, size and density, in channel bed sediments at 40 sites across urban, suburban and rural river catchments in northwest England. Microplastic contamination was pervasive on all river channel beds. We found multiple urban contamination hotspots with a maximum microplastic concentration of approximately 517,000 particles m-2. After a period of severe flooding in winter 2015/16, all sites were resampled. Microplastic concentrations had fallen at 28 sites and 18 saw a decrease of one order of magnitude. The flooding exported approximately 70% of the microplastic load stored on these river beds (equivalent to 0.85 ± 0.27 tonnes or 43 ± 14 billion particles) and eradicated microbead contamination at 7 sites. We conclude that microplastic contamination is efficiently flushed from river catchments during flooding.

Prospects for separating heavy metal from contaminated soil

International Nuclear Information System (INIS)

Langen, M.; Hoberg, H.; Hamacher, B.

1994-01-01

For decades, large quantities of organic and inorganic pollutants have been brought into the soil as a result of the industrial operations of smelting and coking plants. This paper reports on the prospects of separating heavy metals from soil contaminated by smelting and coking plants by means of a physical/chemical washing procedure. Besides the description of virgin soil characteristics, cleaning results and process parameters of calssification, density separation and flotation processes are presented. It is shown that heavy metal pollution of virgin soil can be reduced by the classical process stages of soil washing. The metal content of virgin soil are critically assessed whereby the limits of the physical-chimical washing process will also be entered into. Emphasis is placed on the significance of the determination of limiting values for inorganic contamination, especially for soil contaminated with both organic and inorganic pollution. (orig.) [de

Remediation of Diesel Fuel Contaminated Sandy Soil using Ultrasonic Waves

Directory of Open Access Journals (Sweden)

Wulandari P.S.

2010-01-01

Full Text Available Ultrasonic cleaning has been used in industry for some time, but the application of ultrasonic cleaning in contaminated soil is just recently received considerable attention, it is a very new technique, especially in Indonesia. An ultrasonic cleaner works mostly by energy released from the collapse of millions of microscopic cavitations near the dirty surface. This paper investigates the use of ultrasonic wave to enhance remediation of diesel fuel contaminated sandy soil considering the ultrasonic power, soil particle size, soil density, water flow rate, and duration of ultrasonic waves application.

Effects of chemical contamination on HDPE - thermo-mechanical and characterisation properties

International Nuclear Information System (INIS)

Ashraf, G.

2002-01-01

Studying the effects of chemical contamination on HDPE is an important precursor in recycling of plastic packaging and polymer reprocessing. This research involves and discusses the results of an in-depth investigation into the effects of chemically contaminating, using various acids, commercial grade high density polyethylene (HDPE) used commonly in packaging applications. An extensive formulation study was conducted and it became obvious that in some cases degradation had occurred to HDPE when chemically contaminated with particular functional group types. The functional groups in contaminated HDPE were successfully identified. A variety of analytical techniques such as Fourier transform Infra-red spectroscopy, X-ray Florescence, x-ray photo electron spectroscopy could identify compounds such as HCl acid, HNO/sub 3/ acid and other related contaminants. Some chemical additives had effects on the mechanical and thermal properties when added in the most appropriate concentration. The results have shown lower tensile modulus and strength tensile elongation, lower modular weight, melt flow index and crystallinity. The amount of contaminant concentration, the type of chemical functional groups used and the type of test selected to affect degradation are important factors in proving the effects of chemical contamination on HDPE in the melt state. (author)

Food contamination : lessons of Chernobyl

International Nuclear Information System (INIS)

Haque, F.

1987-01-01

This brief survey of radioactive contamination of food suggests at least four areas in which action needs to be taken so that we might be better prepared to respond to any possible future nuclear accident. More research is needed on the way that radiation enters the food chain, and the measures that can be taken to counter the health hazards posed by fallout. A second clear need is for a global radioactivity monitoring system. Third, international standards need to be established for methods of sampling, analysis and reporting of the radioactive levels in foods. Finally, an effort must be made to inform the public so it can distinguish between the real and the imaginary hazards posed by radioactively contaminated foods

Regulatory control in the rehabilitation of contaminated sites in Syria

International Nuclear Information System (INIS)

Shweikani, R.; Suman, H.

2002-01-01

The work described in this paper is concerning the regulatory control set by the Atomic Energy Commission of Syria (AECS) for the contaminated sites with Naturally Occurring Radioactive Materials (NORM) in the oil industries in the northeast of Syria. These sites lie in a desert region with poor population density and low occupancy. The decision was made to use the activity concentration of 226 Ra per unit mass as a measure to identify the need for cleanup. Two limits were set for this purpose so that contamination concentration above the higher limit is defined as waste that has to be excavated from the site, while contamination concentration between the two limits can be dealt with on site. Contamination concentration below the lower limit was looked at as acceptable. Remediation plan to transfer the contaminated soil, with radium concentration over the higher limit, to an engineered disposal pit was adopted. Proper stabilisation measures and environmental monitoring programme were requested by the AECS and considered as essential parts of the remediation plan. (author)

Toxicological Benchmarks for Screening Potential Contaminants of Concern for Effects on Terrestrial Plants

Energy Technology Data Exchange (ETDEWEB)

Suter, G.W. II

1993-01-01

One of the initial stages in ecological risk assessment for hazardous waste sites is screening contaminants to determine which of them are worthy of further consideration as contaminants of potential concern. This process is termed contaminant screening. It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 38 chemicals potentially associated with United States Department of Energy (DOE) sites. In addition, background information on the phytotoxicity and occurrence of the chemicals in soils is presented, and literature describing the experiments from which data were drawn for benchmark derivation is reviewed. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern.

1993 Proceedings volume 1--Contamination control; symposium on minienvironments; symposium on biocontamination control

International Nuclear Information System (INIS)

Anon.

1993-01-01

Volume 1 contains the proceedings from three symposia. Contamination Control includes the following topics: Atmospheric pressure ionization mass spectroscopy (APIMS) applications; APIMS development; contamination control in cleanroom air; defect reduction in semiconductor processes; contamination control in the aerospace industry; filtration of gases; ultrapure chemical and DI water; filtration of chemicals; wafer cleaning/trace contaminant effects; wafer cleaning techniques; detection of particles in UHP fluids; detection of surface particles; modeling contamination; detection of surface organics; modeling, particle transport, deposition, and removal; and detection of surface metallics. Symposium on Minienvironments includes the following: design of minienvironments; robotics and I/O transport; testing, methods, and standards. The Symposium on Biocontamination Control includes the following: microbial CC facility requirements in pharmaceutical, biological, and medical device manufacture; cleaning and disinfecting methods and devices for bio CC; biocontamination control devices, methodology, and standards, airborne and surface microbial monitoring methods and devices; and regulatory issues in bio CC--present and future. All papers within the scope of the Energy Data Base have been processed separately for inclusion on the data base

Technical Basis - Spent Nuclear Fuels (SNF) Project Radiation and Contamination Trending Program

International Nuclear Information System (INIS)

ELGIN, J.C.

2000-01-01

This report documents the technical basis for the Spent Nuclear Fuel (SNF) Program radiation and contamination trending program. The program consists of standardized radiation and contamination surveys of the KE Basin, radiation surveys of the KW basin, radiation surveys of the Cold Vacuum Drying Facility (CVD), and radiation surveys of the Canister Storage Building (CSB) with the associated tracking. This report also discusses the remainder of radiological areas within the SNFP that do not have standardized trending programs and the basis for not having this program in those areas

Development of a personalized dosimetric tool for radiation protection in case of internal contamination and targeted radiotherapy in nuclear medicine; Developpement d'un outil dosimetrique personnalise pour la radioprotection en contamination interne et la radiotherapie vectorisee en medecine nucleaire

Energy Technology Data Exchange (ETDEWEB)

Chiavassa, S

2005-12-15

Current internal dosimetric estimations are based on the M.I.R.D. formalism and used standard mathematical models. These standard models are often far from a given patient morphology and do not allow to perform patient-specific dosimetry. The aim of this study was to develop a personalized dosimetric tool, which takes into account real patient morphology, composition and densities. This tool, called O.E.D.I.P.E., a French acronym of Tool for the Evaluation of Personalized Internal Dose, is a user-friendly graphical interface. O.E.D.I.P.E. allows to create voxel-based patient-specific geometries and associates them with the M.C.N.P.X. Monte Carlo code. Radionuclide distribution and absorbed dose calculation can be performed at the organ and voxel scale. O.E.D.I.P.E. can be used in nuclear medicine for targeted radiotherapy and in radiation protection in case of internal contamination. (author)

Aflatoxin Contamination of Feed Materials in Qom Province, Iran

Directory of Open Access Journals (Sweden)

Mohammad Rezaei

2014-04-01

Full Text Available Background: Aflatoxins are fungal toxins which may be present in some foods and due to their negative health effects, represent a major concern for humans and food industries. In the present study, total aflatoxin contamination in products from eight feed materials production centers located in Qom City of Iran were evaluated by an ELISA technique in November 2012. Methods: A total of 40 feed samples were analyzed for total aflatoxin. The samples were collected randomly from eight feed materials production centers (C1-C8 located in Qom city. Samples were conditioned in sterile plastic container and kept at 4 ᵒC until analyses that were carried out in same day. Results: The total average of Aflatoxins concentration in samples were 1.83µg/kg. All samples demonstrated total aflatoxin levels lower than European Union standard and National Standard of Iran recommended limits. Conclusion: Considering the low values of aflatoxin contamination, maintaining vigilant preventive measures is recommended.These results do not preclude the need for continuing comprehensive studies for aflatoxin contamination.

SUPERCRITICAL FLUID EXTRACTION OF POLYCYCLIC AROMATIC HYDROCARBON MIXTURES FROM CONTAMINATED SOILS

Science.gov (United States)

Highly contaminated (with PAHs) topsoils were extracted with supercritical CO2 to determine the feasibility and mechanism of supercritical fluid extraction (SFE). Effect of SCF density, temperature, cosolvent type and amount, and of slurrying the soil with water were ...

An unusual and persistent contamination of drinking water by cutting oil.

Science.gov (United States)

Rella, R; Sturaro, A; Parvoli, G; Ferrara, D; Doretti, L

2003-02-01

Drinking water contamination by materials, such as cutting oil, used to set up pipelines is an uncommon but possible event. This paper describes the analytical procedures used to identify the components of that contaminant in drinking water. Volatile and semi-volatile chemical species, responsible for an unpleasant taste and odour, were recognised by solid phase microextraction and GC/MS techniques. Among the volatile compounds, the presence of xylenes, bornyl acetate and diphenyl ether was confirmed by certificate standards and quantified in the most contaminated samples.

MYCOTOXINS CONTAMINATION IN EDIBLE LAND SNAIL AT GRAZING PADDOCK ENVIRONMENT

Directory of Open Access Journals (Sweden)

Ime Ebenso

2013-02-01

Full Text Available Mycotoxins contamination of animal products is under reported. Juvenile edible land snails (Archachatina marginata were exposed as sentinels in bottomless metal drums for 1 week at abandoned, new and reference sites respectively at grazing paddock environment, to assess the presence of foodborne microbiological mycotoxins contamination during the dry season. Mycological analysis of A. marginata samples revealed high (p<0.05 contamination at all paddocks ranged from 1.2-1.3 x 105 cfu-g. Results revealed values that were found to be unacceptable by FAO/WHO standards. The presence of Aspergillus niger, A. fumigatus and Penicillum expansum were noted as potential toxicogenic mycoflora. Snails were tolerant to all levels of contamination with no clinical signs of infection or mortality. This finding could serve as basis for assessing pre-slaughter microbial contamination of livestock farm/field environment in order to establish data with comparative epidemiological value, which could highlight early warning signals of food safety risk and cross-contamination of mycotoxins in the food chain.

Assessing the Risk of Secondary Transfer Via Fingerprint Brush Contamination Using Enhanced Sensitivity DNA Analysis Methods.

Science.gov (United States)

Bolivar, Paula-Andrea; Tracey, Martin; McCord, Bruce

2016-01-01

Experiments were performed to determine the extent of cross-contamination of DNA resulting from secondary transfer due to fingerprint brushes used on multiple items of evidence. Analysis of both standard and low copy number (LCN) STR was performed. Two different procedures were used to enhance sensitivity, post-PCR cleanup and increased cycle number. Under standard STR typing procedures, some additional alleles were produced that were not present in the controls or blanks; however, there was insufficient data to include the contaminant donor as a contributor. Inclusion of the contaminant donor did occur for one sample using post-PCR cleanup. Detection of the contaminant donor occurred for every replicate of the 31 cycle amplifications; however, using LCN interpretation recommendations for consensus profiles, only one sample would include the contaminant donor. Our results indicate that detection of secondary transfer of DNA can occur through fingerprint brush contamination and is enhanced using LCN-DNA methods. © 2015 American Academy of Forensic Sciences.

Statistical density modification using local pattern matching

International Nuclear Information System (INIS)

Terwilliger, Thomas C.

2003-01-01

Statistical density modification can make use of local patterns of density found in protein structures to improve crystallographic phases. A method for improving crystallographic phases is presented that is based on the preferential occurrence of certain local patterns of electron density in macromolecular electron-density maps. The method focuses on the relationship between the value of electron density at a point in the map and the pattern of density surrounding this point. Patterns of density that can be superimposed by rotation about the central point are considered equivalent. Standard templates are created from experimental or model electron-density maps by clustering and averaging local patterns of electron density. The clustering is based on correlation coefficients after rotation to maximize the correlation. Experimental or model maps are also used to create histograms relating the value of electron density at the central point to the correlation coefficient of the density surrounding this point with each member of the set of standard patterns. These histograms are then used to estimate the electron density at each point in a new experimental electron-density map using the pattern of electron density at points surrounding that point and the correlation coefficient of this density to each of the set of standard templates, again after rotation to maximize the correlation. The method is strengthened by excluding any information from the point in question from both the templates and the local pattern of density in the calculation. A function based on the origin of the Patterson function is used to remove information about the electron density at the point in question from nearby electron density. This allows an estimation of the electron density at each point in a map, using only information from other points in the process. The resulting estimates of electron density are shown to have errors that are nearly independent of the errors in the original map using

Single-particle energies and density of states in density functional theory

Science.gov (United States)

van Aggelen, H.; Chan, G. K.-L.

2015-07-01

Time-dependent density functional theory (TD-DFT) is commonly used as the foundation to obtain neutral excited states and transition weights in DFT, but does not allow direct access to density of states and single-particle energies, i.e. ionisation energies and electron affinities. Here we show that by extending TD-DFT to a superfluid formulation, which involves operators that break particle-number symmetry, we can obtain the density of states and single-particle energies from the poles of an appropriate superfluid response function. The standard Kohn- Sham eigenvalues emerge as the adiabatic limit of the superfluid response under the assumption that the exchange- correlation functional has no dependence on the superfluid density. The Kohn- Sham eigenvalues can thus be interpreted as approximations to the ionisation energies and electron affinities. Beyond this approximation, the formalism provides an incentive for creating a new class of density functionals specifically targeted at accurate single-particle eigenvalues and bandgaps.

Bioremediation a potential approach for soil contaminated with polycyclic aromatic hydrocarbons: An Overview

OpenAIRE

Norzila Othman; Mohd Irwan Juki; Norhana Hussain; Suhaimi Abdul Talib

2011-01-01

Polycyclic aromatic hydrocarbons (PAHs) represent a group of priority pollutants which are present at high concentration in soils of many industrially contaminated sites. Standards and criteria for the remediation of soils contaminated with PAHs vary widely between countries. Bioremediation has gained preference as a technology for remediation contaminated sites as it is less expensive and more environmental friendly. Bioremediation utilizes microorganisms to degrade PAHs to less toxic compou...

EVALUATION OF TECHNOLOGIES FOR IN SITU CLEANUP OF DNAPL CONTAMINATED SITES

Science.gov (United States)

Ground water contamination by non-aqueous phase liquids poses one of the greatest remedial challenges in the field of environmental engineering. Denser-than-water non-aqueous phase liquids (DNAPLs) are especially problematic due to their low water solubility, high density, an...

Development of a personalized dosimetric tool for radiation protection in case of internal contamination and targeted radiotherapy in nuclear medicine; Developpement d'un outil dosimetrique personnalise pour la radioprotection en contamination interne et la radiotherapie vectorisee en medecine nucleaire

Energy Technology Data Exchange (ETDEWEB)

Chiavassa, S

2005-12-15

Current internal dosimetric estimations are based on the M.I.R.D. formalism and used standard mathematical models. These standard models are often far from a given patient morphology and do not allow to perform patient-specific dosimetry. The aim of this study was to develop a personalized dosimetric tool, which takes into account real patient morphology, composition and densities. This tool, called O.E.D.I.P.E., a French acronym of Tool for the Evaluation of Personalized Internal Dose, is a user-friendly graphical interface. O.E.D.I.P.E. allows to create voxel-based patient-specific geometries and associates them with the M.C.N.P.X. Monte Carlo code. Radionuclide distribution and absorbed dose calculation can be performed at the organ and voxel scale. O.E.D.I.P.E. can be used in nuclear medicine for targeted radiotherapy and in radiation protection in case of internal contamination. (author)

Remedial action standards for inactive uranium processing sites (40 cfr 192). Draft environmental impact statement

International Nuclear Information System (INIS)

1980-12-01

The Environmental Protection Agency is proposing standards for disposing of uranium mill tailings from inactive processing sites and for cleaning up contaminated open land and buildings. These standards were developed pursuant to the Uranium Mill Tailings Radiation Control Act of 1978 (Public Law 95-604). This Act requires EPA to promulgate standards to protect the environment and public health and safety from radioactive and nonradioactive hazards posed by uranium mill tailings at designated inactive processing sites. The Draft Environmental Impact Statement examines health, technical, cost, and other factors relevant to determining standards. The proposed standards for disposal of the tailings piles cover radon emissions from the tailings to the air, protection of surface and ground water from radioactive and nonradioactive contaminants, and the length of time the disposal system should provide a reasonable expectation of meeting these standards. The proposed cleanup standards limit indoor radon decay product concentrations and gamma radiation levels and the residual radium concentration of contaminated land after cleanup

Effect of mobile unidirectional air flow unit on microbial contamination of air in standard urologic procedures.

Science.gov (United States)

Ferretti, Stefania; Pasquarella, Cesira; Fornia, Samanta; Saccani, Elisa; Signorelli, Carlo; Vitali, Pietro; Sansebastiano, Giuliano Ezio

2009-12-01

Infection is one of the most feared complications of surgery. New instrumentation is being developed to reduce deposition of bacteria. We investigated 45 major surgical procedures (21 radical nephrectomies [RN] and 24 radical retropubic prostatectomies [RRP]) in our urology department during 2007. In about one-half of the interventions, an ultraclean air flow mobile (UAF) unit was used. Bacterial sedimentation was evaluated by nitrocellulose membranes placed on the instrument tray and by settle plates positioned at four points in the operating room. In 27 operations, an additional membrane was located near the incision. Bacterial counts on the nitrocellulose membranes during RN were 230 colony-forming units (cfu)/m(2)/h with the UAF unit and 2,254 cfu/m(2)/h without the unit (p = 0.001). During RRP, the values were 288 cfu/m(2)/h and 3,126 cfu/m(2)/h respectively (p = 0.001). The membrane placed near the incision during RN showed a microbial count of 1,235 cfu/m(2)/h with the UAF unit and 5,093 cfu/m(2)/h without the unit (p = 0.002); during RRP, the values were 1,845 cfu/m(2)/h and 3,790 cfu/m(2)/h, respectively (difference not significant). Bacterial contamination detected by settle plates during RN showed a mean value of 2,273 cfu/m(2)/h when the UAF unit was used and 2,054 cfu/m(2)/h without the unit; during RRP, the values were 2,332 cfu/m(2)/h and 2,629 cfu/m(2)/h with and without the UAF unit, respectively (NS). No statistically significant differences were detected in the clinical data registered in patients operated on under standard conditions and while the UAF unit was functioning. The UAF appears able to reduce microbial contamination at the operating table, reaching a bacterial number obtained in ultraclean operating theatres.

Density and surface tension of ionic liquids.

Science.gov (United States)

Kolbeck, C; Lehmann, J; Lovelock, K R J; Cremer, T; Paape, N; Wasserscheid, P; Fröba, A P; Maier, F; Steinrück, H-P

2010-12-30

We measured the density and surface tension of 9 bis[(trifluoromethyl)sulfonyl]imide ([Tf(2)N](-))-based and 12 1-methyl-3-octylimidazolium ([C(8)C(1)Im](+))-based ionic liquids (ILs) with the vibrating tube and the pendant drop method, respectively. This comprehensive set of ILs was chosen to probe the influence of the cations and anions on density and surface tension. When the alkyl chain length in the [C(n)C(1)Im][Tf(2)N] series (n = 1, 2, 4, 6, 8, 10, 12) is increased, a decrease in density is observed. The surface tension initially also decreases but reaches a plateau for alkyl chain lengths greater than n = 8. Functionalizing the alkyl chains with ethylene glycol groups results in a higher density as well as a higher surface tension. For the dependence of density and surface tension on the chemical nature of the anion, relations are only found for subgroups of the studied ILs. Density and surface tension values are discussed with respect to intermolecular interactions and surface composition as determined by angle-resolved X-ray photoelectron spectroscopy (ARXPS). The absence of nonvolatile surface-active contaminants was proven by ARXPS.

A Large and Pristine Sample of Standard Candles across the Milky Way: ∼100,000 Red Clump Stars with 3% Contamination

Science.gov (United States)

Ting, Yuan-Sen; Hawkins, Keith; Rix, Hans-Walter

2018-05-01

Core helium-burning red clump (RC) stars are excellent standard candles in the Milky Way. These stars may have more precise distance estimates from spectrophotometry than from Gaia parallaxes beyond 3 kpc. However, RC stars have values of T eff and {log}g that are very similar to some red giant branch (RGB) stars. Especially for low-resolution spectroscopic studies where T eff, {log}g, and [Fe/H] can only be estimated with limited precision, separating RC stars from RGB through established methods can incur ∼20% contamination. Recently, Hawkins et al. demonstrated that the additional information in single-epoch spectra, such as the C/N ratio, can be exploited to cleanly differentiate RC and RGB stars. In this second paper of the series, we establish a data-driven mapping from spectral flux space to independently determined asteroseismic parameters, the frequency and the period spacing. From this, we identify 210,371 RC stars from the publicly available LAMOST DR3 and APOGEE DR14 data, with ∼9% of contamination. We provide an RC sample of 92249 stars with a contamination of only ∼3%, by restricting the combined analysis to LAMOST stars with S/Npix ≥ 75. This demonstrates that high-signal-to-noise ratio (S/N), low-resolution spectra covering a broad wavelength range can identify RC samples at least as pristine as their high-resolution counterparts. As coming and ongoing surveys such as TESS, DESI, and LAMOST will continue to improve the overlapping training spectroscopic-asteroseismic sample, the method presented in this study provides an efficient and straightforward way to derive a vast yet pristine sample of RC stars to reveal the three-dimensional (3D) structure of the Milky Way.

Contamination and infection transmission in dental practice in ...

African Journals Online (AJOL)

most of dental clinics in Tanzania are a part of a hospital or health centre. So when one talks on the subject of contamination and infection transmission in ... emergencies or field work. Dust is a ... standard of cleanliness outlined above, control.

Toward a standard method for determination of waterborne radon

International Nuclear Information System (INIS)

Vitz, E.

1990-01-01

When the USEPA specifies the maximum contaminant level (MCL) for any contaminant, a standard method for analysis must be simultaneously stipulated. Promulgation of the proposed MCL and standard method for radon in drinking water is expected by early next year, but a six-month comment period and revision will precede final enactment. The standard method for radon in drinking water will probably specify that either the Lucas cell technique or liquid scintillation spectrometry be used. This paper reports results which support a standard method with the following features: samples should be collected by an explicitly stated technique to control degassing, in glass vials with or without scintillation cocktail, and possibly in duplicate; samples should be measured by liquid scintillation spectroscopy in a specified energy window', in a glass vial with particular types of cocktails; radium standards should be prepared with controlled quench levels and specified levels of carriers, but radium-free controls prepared by a specified method should be used in interlaboratory comparison studies

Automatic pellet density checking machine using vision technique

International Nuclear Information System (INIS)

Kumar, Suman; Raju, Y.S.; Raj Kumar, J.V.; Sairam, S.; Sheela; Hemantha Rao, G.V.S.

2012-01-01

Uranium di-oxide powder prepared through chemical process is converted to green pellets through the powder metallurgy route of precompaction and final compaction operations. These green pellets are kept in a molybdenum boat, which consists of a molybdenum base and a shroud. The boats are passed through the high temperature sintering furnaces to achieve required density of pellets. At present MIL standard 105 E is followed for measuring density of sintered pellets in the boat. As per AQL 2.5 of MIL standard, five pellets are collected from each boat, which contains approximately 800 nos of pellets. The densities of these collected pellets are measured. If anyone pellet density is less than the required value, the entire boat of pellets are rejected and sent back for dissolution for further processing. An Automatic Pellet Density Checking Machine (APDCM) was developed to salvage the acceptable density pellets from the rejected boat of pellets

Development of a standard data base for FBR core nuclear design. 10. Reevaluation of atomic number density of JOYO Mk-II core

Energy Technology Data Exchange (ETDEWEB)

Numata, Kazuyuki; Sato, Wakaei [Japan Nuclear Cycle Development Inst., Oarai, Ibaraki (Japan). Oarai Engineering Center; Ishikawa, Makoto; Arii, Yoshio [Nuclear Energy System Incorporation, Tokyo (Japan)

1999-07-01

The material composition of JOYO Mk-II core components in its initial core was reevaluated as a part of the effort for developing a standard data base for FBR core nuclear design. The special feature of the reevaluation is to treat the decay of Pu-241 isotope, so that the atomic number densities of Pu-241 and Am-241 in fuel assemblies can be exactly evaluated on the initial critical date, Nov. 22nd, 1982. Further, the atomic number densities of other core components were also evaluated to improve the analytical accuracy. Those include the control rods which were not so strictly evaluated in the past, and the dummy fuels and the neutron sources which were not treated in the analytical model so far. The results of the present reevaluation were as follows: (1) The changes of atomic number densities of the major nuclides such as Pu-239, U-235 and U-238 were about {+-}0.2 to 0.3%. On the other hand, the number density of Pu-241, which was the motivation of the present work, was reduced by 12%. From the fact, the number densities in the past analysis might be based on the isotope measurement of the manufacturing point of time without considering the decay of Pu-241. (2) As the other core components, the number densities of control rods and outer reflector-type A were largely improved. (author)

GIS-based Assessment of Arsenic Contamination of Water Supplies in Rural Areas of Rivash Town: Comparisons with National and WHO Standards

Directory of Open Access Journals (Sweden)

Hossein Alidadi

2017-01-01

Full Text Available Arsenic is one of the most hazardous elements in drinking water. Water contaminated with arsenic causes a variety of diseases in humans including cancer. The present study was conducted to survey Arsenic concentration in rural water resources in Rivash Twon, Kashmar, Iran. For the purposes of this cross-sectional study, 60 samples were collected from 10 underground drinking water supplies during the period from April to June, 2013. Samplings and sample preservation were performed according to standard methods. Measurements were performed via the VGA method using atomic absorption. Such water quality parameters as pH, TDS, EC, residual chlorine, and temperaturte were also measured to determine any relationships likely to exist between As concentration and the parameters measured. As levels were then compared with national and international standards. It was found that the average values of As concentration at the stations A, B, C, D, E, F, G, H, I, and J were 1.53±1.03, 1.30±1.07, 10.55±3.83, 11.21±5.01, 10.57±3.68, 2.34±0.73, 3.22±0.58, 9.89±3.57, 10.48±5.07, and 2.23±0.53 µg/L-1, respectively. As concentrations at five stations were found to be higher than the values recommended in WHO guidelines; the remaining stations revealed values below the national standard. While the differences between As level and the national standard were statistically significant (p

Measurement of loose powder density

International Nuclear Information System (INIS)

Akhtar, S.; Ali, A.; Haider, A.; Farooque, M.

2011-01-01

Powder metallurgy is a conventional technique for making engineering articles from powders. Main objective is to produce final products with the highest possible uniform density, which depends on the initial loose powder characteristics. Producing, handling, characterizing and compacting materials in loose powder form are part of the manufacturing processes. Density of loose metallic or ceramic powder is an important parameter for die design. Loose powder density is required for calculating the exact mass of powder to fill the die cavity for producing intended green density of the powder compact. To fulfill this requirement of powder metallurgical processing, a loose powder density meter as per ASTM standards is designed and fabricated for measurement of density. The density of free flowing metallic powders can be determined using Hall flow meter funnel and density cup of 25 cm/sup 3/ volume. Density of metal powders like cobalt, manganese, spherical bronze and pure iron is measured and results are obtained with 99.9% accuracy. (author)

Cadmium contamination in cereal-based diets and diet ingredients

International Nuclear Information System (INIS)

Siitonen, P.H.; Thompson, H.C. Jr.

1990-01-01

Cereal-based diet and/or diet ingredient cadmium levels were determined by graphite furnace AAS. Cadmium contamination was 88.3 and 447 ppb in two cereal-based diets, 44.6 and 48.9 ppb in two purified diets, and ranged from less than 1.1 to 22,900 ppb in the ingredients of one cereal-based diet. The major source of cadmium contamination was attributed to the calcium supplement used for diet formulation. Comparative analyses of two purified diet samples and one cereal-based diet by the National Institute of Standards and Technology (NIST, formerly the National Bureau of Standards) and the National Center for Toxicological Research (NCTR) gave virtually identical results for Cd. A comparative study of Cd levels determined by flame and furnace AAS was also made by the NCTR and the NIST

Long-term field phytoextraction of zinc/cadmium contaminated soil by Sedum plumbizincicola under different agronomic strategies.

Science.gov (United States)

Deng, Lin; Li, Zhu; Wang, Jie; Liu, Hongyan; Li, Na; Wu, Longhua; Hu, Pengjie; Luo, Yongming; Christie, Peter

2016-01-01

In two long-term field experiments the zinc (Zn)/cadmium (Cd) hyperaccumulator Sedum plumbizincicola (S. plumbizincicola) was examined to optimize the phytoextraction of metal contaminated soil by two agronomic strategies of intercropping with maize (Zea mays) and plant densities. Soil total Zn and Cd concentrations decreased markedly after long-term phytoextraction. But shoot biomass and Cd and Zn concentrations showed no significant difference with increasing remediation time. In the intercropping experiment the phytoremediation efficiency in the treatment "S. plumbizincicola intercropped with maize" was higher than in S. plumbizincicola monocropping, and Cd concentrations of corn were below the maximum national limit. In the plant density experiment the phytoremediation efficiency increased with increasing plant density and 440,000 plants ha(-1) gave the maximum rate. These results indicated that S. plumbizincicola at an appropriate planting density and intercropped with maize can achieve high remediation efficiency to contaminated soil without affecting the cereal crop productivity. This cropping system combines adequate agricultural production with soil heavy metal phytoextraction.

The Importance of Particle Size in Estimating Downwind Contamination from an RDD

International Nuclear Information System (INIS)

Bauer, T.

2007-01-01

There is general agreement that realistic quantities of radiological material released from a radiological dispersal device (RDD) will not travel more than hundred meters at toxic levels. Of greater concern in the case of such an incident is the size of the area contaminated with radiological particles. Remediation of contaminated areas will require either removal of the deposited articles or disposal of the contaminated materials. Contours of expected contaminated areas have been presented which extend more than 10 miles downwind of the release location. It would be impossible to remediate such a large area, so the likely response will be to permanently seal most of it off from further use. Not only are these radiation contours below levels of concern, the particle size assumed is unreasonably low, especially when the density of radioactive materials is considered. Using of appropriate RDD characterization and range of particle size, this presentation will show that expected contamination areas should be small enough to make remediation feasible.(author)

Bacterial contamination of groundwater in urban area of Karachi

International Nuclear Information System (INIS)

Zubair, A.; Rippey, B.

1999-01-01

Well-water samples (in=193) were collected from urban areas of five districts of Karachi during the period 1993 to 1995 to evaluate its bacteriological quality and their impact on city environment and morbidity patterns of inhabitants. Samples were analyzed by the standard method American Public Health Association. The bacteriological contamination level suggest that the groundwater of Chaahi is mainly affected by contamination of wastewater containing high levels of coliform and faecal coliform bacteria. This study points towards serious need to control the seepage from sewerage system and use of contaminated well-water should be discouraged to reduce the incidence of water-borne diseases in order to improve the quality of life and health. (author)

Current Status of Mycotoxin Contamination of Food Commodities in Zimbabwe

Directory of Open Access Journals (Sweden)

Nancy Nleya

2018-05-01

Full Text Available Agricultural products, especially cereal grains, serve as staple foods in sub-Saharan Africa. However, climatic conditions in this region can lead to contamination of these commodities by moulds, with subsequent production of mycotoxins posing health risks to both humans and animals. There is limited documentation on the occurrence of mycotoxins in sub-Saharan African countries, leading to the exposure of their populations to a wide variety of mycotoxins through consumption of contaminated foods. This review aims at highlighting the current status of mycotoxin contamination of food products in Zimbabwe and recommended strategies of reducing this problem. Zimbabwe is one of the African countries with very little information with regards to mycotoxin contamination of its food commodities, both on the market and at household levels. Even though evidence of multitoxin occurrence in some food commodities such as maize and other staple foods exist, available published research focuses only on Aspergillus and Fusarium mycotoxins, namely aflatoxins, deoxynivalenol (DON, trichothecenes, fumonisins, and zearalenone (ZEA. Occurrence of mycotoxins in the food chain has been mainly associated with poor agricultural practices. Analysis of mycotoxins has been done mainly using chromatographic and immunological methods. Zimbabwe has adopted European standards, but the legislation is quite flexible, with testing for mycotoxin contamination in food commodities being done voluntarily or upon request. Therefore, the country needs to tighten its legislation as well as adopt stricter standards that will improve the food safety and security of the masses.

Current Status of Mycotoxin Contamination of Food Commodities in Zimbabwe.

Science.gov (United States)

Nleya, Nancy; Adetunji, Modupeade Christianah; Mwanza, Mulunda

2018-05-03

Agricultural products, especially cereal grains, serve as staple foods in sub-Saharan Africa. However, climatic conditions in this region can lead to contamination of these commodities by moulds, with subsequent production of mycotoxins posing health risks to both humans and animals. There is limited documentation on the occurrence of mycotoxins in sub-Saharan African countries, leading to the exposure of their populations to a wide variety of mycotoxins through consumption of contaminated foods. This review aims at highlighting the current status of mycotoxin contamination of food products in Zimbabwe and recommended strategies of reducing this problem. Zimbabwe is one of the African countries with very little information with regards to mycotoxin contamination of its food commodities, both on the market and at household levels. Even though evidence of multitoxin occurrence in some food commodities such as maize and other staple foods exist, available published research focuses only on Aspergillus and Fusarium mycotoxins, namely aflatoxins, deoxynivalenol (DON), trichothecenes, fumonisins, and zearalenone (ZEA). Occurrence of mycotoxins in the food chain has been mainly associated with poor agricultural practices. Analysis of mycotoxins has been done mainly using chromatographic and immunological methods. Zimbabwe has adopted European standards, but the legislation is quite flexible, with testing for mycotoxin contamination in food commodities being done voluntarily or upon request. Therefore, the country needs to tighten its legislation as well as adopt stricter standards that will improve the food safety and security of the masses.

Public health risk assessment of groundwater contamination in Batman, Turkey.

Science.gov (United States)

Nalbantcilar, M Tahir; Pinarkara, Sukru Yavuz

2016-08-01

In this study, a comprehensive analysis of groundwater was performed to assess contamination and phenol content in Batman, Turkey, particularly in residential areas near agriculture, livestock and oil industry facilities. From these areas, where potentially contaminated groundwater used for drinking and irrigation threatens public health, 30 groundwater samples were collected and analyzed for heavy metal concentrations (Al, As, B, Ba, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, Li, Mg, Mn, Mo, Na, Ni, NO3, P, Pb, phenol, S, Sb, Se, SO4, Sr, U, and Zn). Compared with the standards of the Environmental Protection Agency, Al, Fe, and Mn concentrations in groundwater exceeded secondary drinking water regulations, NO3 concentrations were high for maximum contaminant levels, and As, Pb, and U concentrations exceeded maximum contaminant level goals in all samples. Ni, Sb, and Se concentrations also exceeded limits set by the Turkish Standards Institution. Nearly all samples revealed concentrations of Se, Sb, Hg, and phenol due to nearby petroleum refineries, oil storage plants, and agricultural and livestock areas. The results obtained from this study indicate that the groundwater in Batman contains elements in concentrations that approach or exceed limits and thus threatens public health with increased blood cholesterol, decreased blood sugar, and circulatory problems.

Natural uranium toxicology - evaluation of internal contamination in man; Toxicologie de l'uranium naturel - essai d'evaluation de la contamination interne chez l'homme

Energy Technology Data Exchange (ETDEWEB)

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

1968-07-01

After reminding the physical and chemical properties of natural uranium which might affect its toxicology, a comprehensive investigation upon natural uranium metabolism and toxicity and after applying occupational exposure standards to this particular poison, it has been determined, from accident reports and human experience reported in the related literature, a series of formulae obtained by theoretical mathematical development giving principles for internal contamination monitoring and disclosure by determining uranium in the urine of occupationally exposed individuals. An assay is performed to determine individual internal contamination according to the various contamination cases. The outlined purposes, mainly practical, required some options and extrapolations. The proposed formula allows a preliminary approach and also to determine shortly a contamination extent or to discuss the systematical urinalysis results as compared with individual radio-toxicology monitoring professional standards. (author) [French] Apres le rappel des caracteristiques physiques et des proprietes chimiques de l'uranium naturel pouvant avoir une influence sur sa toxicologie, l'etude detaillee de son metabolisme et de sa toxicite, puis l'application des normes professionnelles d'exposition au cas particulier de ce toxique, il est etabli, a partir des comptes rendus d'accidents et de l'experimentation humaine rapportes dans la litterature, une serie de formules obtenues par developpement mathematique theorique qui posent les principes de la surveillance et de la mise en evidence de la contamination interne par la recherche et le dosage de l'uranium dans les urines d'individus professionnellement exposes. Un essai d'evaluation de la contamination interne individuelle suivant les differents cas de contamination est effectue. Le formulaire propose permet de faire une premiere approximation et d'apprecier rapidement l'importance d

Quantitative risk assessment of drinking water contaminants

International Nuclear Information System (INIS)

Cothern, C.R.; Coniglio, W.A.; Marcus, W.L.

1986-01-01

The development of criteria and standards for the regulation of drinking water contaminants involves a variety of processes, one of which is risk estimation. This estimation process, called quantitative risk assessment, involves combining data on the occurrence of the contaminant in drinking water and its toxicity. The human exposure to a contaminant can be estimated from occurrence data. Usually the toxicity or number of health effects per concentration level is estimated from animal bioassay studies using the multistage model. For comparison, other models will be used including the Weibull, probit, logit and quadratic ones. Because exposure and toxicity data are generally incomplete, assumptions need to be made and this generally results in a wide range of certainty in the estimates. This range can be as wide as four to six orders of magnitude in the case of the volatile organic compounds in drinking water and a factor of four to five for estimation of risk due to radionuclides in drinking water. As examples of the differences encountered in risk assessment of drinking water contaminants, discussions are presented on benzene, lead, radon and alachlor. The lifetime population risk estimates for these contaminants are, respectively, in the ranges of: <1 - 3000, <1 - 8000, 2000-40,000 and <1 - 80. 11 references, 1 figure, 1 table

Dynamics of neurotic frustration of teenagers living in radioactive contaminated regions

International Nuclear Information System (INIS)

Obukhov, S.G.

1999-01-01

Clinical psycho pathologic and psychologic examination of 150 teenagers (236 boys and 274 girls) living in radioactive contaminated regions (contaminated density of cesium 137 was 1,5 - 22 Ci/km 2 ) was fulfilled for neurotic frustration dynamics determination. Neurotic disorders of various degrees (from subclinical ones to those clinically diagnosed) such as vegetative dysfunction and frustration of adaptation were revealed in 42% of the examined patients. Therapeutic and rehabilitation measures resulted in positive changes reflecting the psycho pathologic symptoms reduction and stabilisation of a psycho emotional and vegetative state

Monte Carlo study of voxel S factor dependence on tissue density and atomic composition

Energy Technology Data Exchange (ETDEWEB)

Amato, Ernesto, E-mail: eamato@unime.it [University of Messina, Department of Biomedical Sciences and of Morphologic and Functional Imaging, Section of Radiological Sciences, via Consolare Valeria, 1, I-98125 Messina (Italy); Italiano, Antonio [INFN – Istituto Nazionale di Fisica Nucleare, Gruppo Collegato di Messina (Italy); Baldari, Sergio [University of Messina, Department of Biomedical Sciences and of Morphologic and Functional Imaging, Section of Radiological Sciences, via Consolare Valeria, 1, I-98125 Messina (Italy)

2013-11-21

Voxel dosimetry is a common approach to the internal dosimetry of non-uniform activity distributions in nuclear medicine therapies with radiopharmaceuticals and in the estimation of the radiation hazard due to internal contamination of radionuclides. Aim of the present work is to extend our analytical approach for the calculation of voxel S factors to materials different from the soft tissue. We used a Monte Carlo simulation in GEANT4 of a voxelized region of each material in which the source of monoenergetic electrons or photons was uniformly distributed within the central voxel, and the energy deposition was scored over the surrounding 11×11×11 voxels. Voxel S factors were obtained for the following standard ICRP materials: Adipose tissue, Bone cortical, Brain, Lung, Muscle skeletal and Tissue soft with 1 g cm{sup −3} density. Moreover, we considered the standard ICRU materials: Bone compact and Muscle striated. Voxel S factors were represented as a function of the “normalized radius”, defined as the ratio between the source–target voxel distance and the voxel side. We found that voxel S factors and related analytical fit functions are mainly affected by the tissue density, while the material composition gives only a slight contribution to the difference between data series, which is negligible for practical purposes. Our results can help in broadening the dosimetric three-dimensional approach based on voxel S factors to other tissues where diagnostic and therapeutic radionuclides can be taken up and radiation can propagate.

Monte Carlo study of voxel S factor dependence on tissue density and atomic composition

International Nuclear Information System (INIS)

Amato, Ernesto; Italiano, Antonio; Baldari, Sergio

2013-01-01

Voxel dosimetry is a common approach to the internal dosimetry of non-uniform activity distributions in nuclear medicine therapies with radiopharmaceuticals and in the estimation of the radiation hazard due to internal contamination of radionuclides. Aim of the present work is to extend our analytical approach for the calculation of voxel S factors to materials different from the soft tissue. We used a Monte Carlo simulation in GEANT4 of a voxelized region of each material in which the source of monoenergetic electrons or photons was uniformly distributed within the central voxel, and the energy deposition was scored over the surrounding 11×11×11 voxels. Voxel S factors were obtained for the following standard ICRP materials: Adipose tissue, Bone cortical, Brain, Lung, Muscle skeletal and Tissue soft with 1 g cm −3 density. Moreover, we considered the standard ICRU materials: Bone compact and Muscle striated. Voxel S factors were represented as a function of the “normalized radius”, defined as the ratio between the source–target voxel distance and the voxel side. We found that voxel S factors and related analytical fit functions are mainly affected by the tissue density, while the material composition gives only a slight contribution to the difference between data series, which is negligible for practical purposes. Our results can help in broadening the dosimetric three-dimensional approach based on voxel S factors to other tissues where diagnostic and therapeutic radionuclides can be taken up and radiation can propagate

Impact of urban contamination of the La Paz River basin on thermotolerant coliform density and occurrence of multiple antibiotic resistant enteric pathogens in river water, irrigated soil and fresh vegetables.

Science.gov (United States)

Poma, Violeta; Mamani, Nataniel; Iñiguez, Volga

2016-01-01

La Paz River in Andean highlands is heavily polluted with urban run-off and further contaminates agricultural lowlands and downstream waters at the Amazon watershed. Agricultural produce at this region is the main source of vegetables for the major Andean cities of La Paz and El Alto. We conducted a 1 year study, to evaluate microbial quality parameters and occurrence of multiple enteropathogenic bacteria (Enterohemorrhagic E. coli-EHEC, Enteroinvasive E. coli or Shigella-EIEC/Shigella, Enteroaggregative E. coli-EAEC, Enteropathogenic E. coli-EPEC Enterotoxigenic E. coli-ETEC and Salmonella) and its resistance to 11 antibiotics. Four sampling locations were selected: a fresh mountain water reservoir (un-impacted, site 1) and downstream sites receiving wastewater discharges (impacted, sites 2-4). River water (sites 1-4, N = 48), and soil and vegetable samples (site 3, N = 24) were collected during dry (April-September) and rainy seasons (October-March). Throughout the study, thermotolerant coliform density values at impacted sites greatly exceeded the guidelines for recreational and agricultural water uses. Seasonal differences were found for thermotolerant coliform density during dry season in water samples nearby a populated and hospital compound area. In contrast to the un-impacted site, where none of the tested enteropathogens were found, 100 % of surface water, 83 % of soil and 67 % of vegetable samples at impacted sites, were contaminated with at least one enteropathogen, being ETEC and Salmonella the most frequently found. ETEC isolates displayed different patterns of toxin genes among sites. The occurrence of enteropathogens was associated with the thermotolerant coliform density. At impacted sites, multiple enteropathogens were frequently found during rainy season. Among isolated enteropathogens, 50 % were resistant to at least two antibiotics, with resistance to ampicillin, nalidixic acid, trimethoprim-sulfamethoxazole and tetracycline commonly

Hartree--Fock density matrix equation

International Nuclear Information System (INIS)

Cohen, L.; Frishberg, C.

1976-01-01

An equation for the Hartree--Fock density matrix is discussed and the possibility of solving this equation directly for the density matrix instead of solving the Hartree--Fock equation for orbitals is considered. Toward that end the density matrix is expanded in a finite basis to obtain the matrix representative equation. The closed shell case is considered. Two numerical schemes are developed and applied to a number of examples. One example is given where the standard orbital method does not converge while the method presented here does

Quality assurance measures and calibration of contamination meters at FAG-Kugelfischer

International Nuclear Information System (INIS)

Schloesser, H.

1992-01-01

The quality assurance measures taken in connection with the production of contamination meters according to the DIN 44801 standard are explained with regard to the individual components of such instruments, which include mechanical, electronic and detector elements. After the relevant calibration procedures have been described, the author proceeds to draw the reader's attention to potentials for error in measurements of surface contamination. (orig.) [de

Analysis of the photophysical properties of zearalenone using density functional theory

Science.gov (United States)

The intrinsic photophysical properties of the resorcylic acid moiety of zearalenone offer a convenient label free method to determine zearalenone levels in contaminated agricultural products. Density functional theory and steady-state fluorescence methods were applied to investigate the role of stru...

correlation between maximum dry density and cohesion of ...

African Journals Online (AJOL)

HOD

investigation on sandy soils to determine the correlation between relative density and compaction test parameter. Using twenty soil samples, they were able to develop correlations between relative density, coefficient of uniformity and maximum dry density. Khafaji [5] using standard proctor compaction method carried out an ...

Geological characterization of contaminated sites near the city of Horsens, Denmark

DEFF Research Database (Denmark)

Andersen, Theis Raaschou; Poulsen, Søren Erbs; Thomsen, Peter

characterization of three contaminated sites situated in urban and semi-urban areas around the city of Horsens in corporation with authorities. The existing data from the three field sites include lithological profiles from boreholes. In order to increase the data density, Electrical Resistivity Tomography (ERT...

Big bang nucleosynthesis - The standard model and alternatives

Science.gov (United States)

Schramm, David N.

1991-01-01

The standard homogeneous-isotropic calculation of the big bang cosmological model is reviewed, and alternate models are discussed. The standard model is shown to agree with the light element abundances for He-4, H-2, He-3, and Li-7 that are available. Improved observational data from recent LEP collider and SLC results are discussed. The data agree with the standard model in terms of the number of neutrinos, and provide improved information regarding neutron lifetimes. Alternate models are reviewed which describe different scenarios for decaying matter or quark-hadron induced inhomogeneities. The baryonic density relative to the critical density in the alternate models is similar to that of the standard model when they are made to fit the abundances. This reinforces the conclusion that the baryonic density relative to critical density is about 0.06, and also reinforces the need for both nonbaryonic dark matter and dark baryonic matter.

Where is New York State relative to cleanup standards for soils contaminated with radioactive materials

International Nuclear Information System (INIS)

Merges, P.J.

1995-01-01

In September 1993, New York State adopted a cleanup guideline for radioactively contaminated sites being remediated for unrestricted release. This paper reviews this cleanup guideline and discusses its implementation by Bureau of Radiation staff. A cleanup guideline (1) has been adopted by the State of New York which applies to residual radiological contamination on sites undergoing remediation for unrestricted use. The guideline is flexible and allows for alternative site cleanup approaches. The application of this guidance by radiation control program staff is discussed herein. There may be a need to revisit properties that were felt to be open-quotes cleanclose quotes previously - but fail to meet the new guidance

Toxicological benchmarks for screening potential contaminants of concern for effects on terrestrial plants. Environmental Restoration Program

Energy Technology Data Exchange (ETDEWEB)

Suter, G.W. II; Will, M.E.; Evans, C.

1993-09-01

One of the initial stages in ecological risk assessment for hazardous waste sites is the screening of contaminants to determine which of them are worthy of further consideration as ``contaminants of potential concern.`` This process is termed ``contaminant screening.`` It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 34 chemicals potentially associated with US Department of Energy (DOE) sites. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern. The purpose of this report is to present plant toxicity data and discuss their utility as benchmarks for determining the hazard to terrestrial plants caused by contaminants in soil. Benchmarks are provided for soils and solutions.

Atmospheric contamination

International Nuclear Information System (INIS)

Gruetter, Juerg

1997-01-01

It is about the levels of contamination in center America, the population's perception on the problem, effects of the atmospheric contamination, effects in the environment, causes of the atmospheric contamination, possibilities to reduce the atmospheric contamination and list of Roeco Swisscontac in atmospheric contamination

Understanding Contamination; Twenty Years of Simulating Radiological Contamination

Energy Technology Data Exchange (ETDEWEB)

Emily Snyder; John Drake; Ryan James

2012-02-01

A wide variety of simulated contamination methods have been developed by researchers to reproducibly test radiological decontamination methods. Some twenty years ago a method of non-radioactive contamination simulation was proposed at the Idaho National Laboratory (INL) that mimicked the character of radioactive cesium and zirconium contamination on stainless steel. It involved baking the contamination into the surface of the stainless steel in order to 'fix' it into a tenacious, tightly bound oxide layer. This type of contamination was particularly applicable to nuclear processing facilities (and nuclear reactors) where oxide growth and exchange of radioactive materials within the oxide layer became the predominant model for material/contaminant interaction. Additional simulation methods and their empirically derived basis (from a nuclear fuel reprocessing facility) are discussed. In the last ten years the INL, working with the Defense Advanced Research Projects Agency (DARPA) and the National Homeland Security Research Center (NHSRC), has continued to develop contamination simulation methodologies. The most notable of these newer methodologies was developed to compare the efficacy of different decontamination technologies against radiological dispersal device (RDD, 'dirty bomb') type of contamination. There are many different scenarios for how RDD contamination may be spread, but the most commonly used one at the INL involves the dispersal of an aqueous solution containing radioactive Cs-137. This method was chosen during the DARPA projects and has continued through the NHSRC series of decontamination trials and also gives a tenacious 'fixed' contamination. Much has been learned about the interaction of cesium contamination with building materials, particularly concrete, throughout these tests. The effects of porosity, cation-exchange capacity of the material and the amount of dirt and debris on the surface are very important factors

Innovative reactive barrier technologies for regional contaminated groundwater

NARCIS (Netherlands)

Merkel, P.; Weiβ, H.; Teutsch, G.; Rijnaarts, H.H.M.

2000-01-01

At many industrial sites inadequate waste disposal, leakages and war damages have led to severe groundwater contamination on a regional scale. Standard hydraulic groundwater remediation methods, such as pump-and-treat, in most cases do not lead to satisfactory results, due to the persistence of

Contaminant bacteria in traditional-packed honey

Directory of Open Access Journals (Sweden)

Hening Tjaturina Pramesti

2007-03-01

Full Text Available Honey may be contaminated by microorganisms during its harvesting, processing, and packaging. Honey selected for clinical purposes must safe, sterile, and contain antimicrobial activity, so it must be evaluated using laboratory testing. The aim of this descriptive laboratory study was to isolate and identify the bacterial contaminant in the traditional-packed honey dealing with the use of honey for medical purposes. the colony forming units of honey sample cultured on blood agar were counted using Stuart bacterial colony counter. The suspected bacterial colonies were isolated and identified based on cultural morphology characteristics. The isolates of suspected bacterial colonies were stained according to Gram and Klein method and then were examined by the biochemical reaction. The results showed that there were two contaminant bacteria. Gram-positive cocci which were presumptively identified as coagulase-negative Staphylococci and gram-positive rods which were presumptively identified as Bacillus subtilis. In conclusion, the contaminant bacteria were regarded as low pathogen bacteria. The subtilin enzyme of B subtilis may cause an allergic reaction and coagulase-negative Staphylococci, Staphylococcus epidermidis is also an opportunist pathogen. Inevitably, for medical purposes, traditional-packed honey must be well filtered, water content above 18%, and standardized sterilization without loss of an antibacterial activity or change in properties.

Effect of Particle-size Distribution on Chemical Washing Experiment of Uranium Contaminated Concrete

International Nuclear Information System (INIS)

Kim, Wan Suk; Kim, Gye Nam; Shon, Dong Bin; Park, Hye Min; Kim, Ki Hong; Lee, Kun Woo; Lee, Ki Won; Moon, Jei Kwon

2011-01-01

Taken down of nuclear institution was radioactive contaminated concrete over 70% of whole waste. Advanced countries have realized the importance of waste processing. Nuclear institutions keep a lot of radioactive contaminated concrete in internal waste storage. Therefore radioactive contaminated concrete disport to whole waste and reduce for self-processing standard concentration may be disposed of inexpensive more than radioactive waste storage. This study uses mechanical and thermal technology for a uranium contaminated concrete process in Korea Atomic Energy Research Institute's radioactive waste storage. Mechanical and thermal technologies are divided based on particle size. Each particles-sized concrete analyzed for uranium contamination using an MCA instrument. A chemical washing experiment was carried out

Suture, synthetic, or biologic in contaminated ventral hernia repair.

Science.gov (United States)

Bondre, Ioana L; Holihan, Julie L; Askenasy, Erik P; Greenberg, Jacob A; Keith, Jerrod N; Martindale, Robert G; Roth, J Scott; Liang, Mike K

2016-02-01

Data are lacking to support the choice between suture, synthetic mesh, or biologic matrix in contaminated ventral hernia repair (VHR). We hypothesize that in contaminated VHR, suture repair is associated with the lowest rate of surgical site infection (SSI). A multicenter database of all open VHR performed at from 2010-2011 was reviewed. All patients with follow-up of 1 mo and longer were included. The primary outcome was SSI as defined by the Centers for Disease Control and Prevention. The secondary outcome was hernia recurrence (assessed clinically or radiographically). Multivariate analysis (stepwise regression for SSI and Cox proportional hazard model for recurrence) was performed. A total of 761 VHR were reviewed for a median (range) follow-up of 15 (1-50) mo: there were 291(38%) suture, 303 (40%) low-density and/or mid-density synthetic mesh, and 167(22%) biologic matrix repair. On univariate analysis, there were differences in the three groups including ethnicity, ASA, body mass index, institution, diabetes, primary versus incisional hernia, wound class, hernia size, prior VHR, fascial release, skin flaps, and acute repair. The unadjusted outcomes for SSI (15.1%; 17.8%; 21.0%; P = 0.280) and recurrence (17.8%; 13.5%; 21.5%; P = 0.074) were not statistically different between groups. On multivariate analysis, biologic matrix was associated with a nonsignificant reduction in both SSI and recurrences, whereas synthetic mesh associated with fewer recurrences compared to suture (hazard ratio = 0.60; P = 0.015) and nonsignificant increase in SSI. Interval estimates favored biologic matrix repair in contaminated VHR; however, these results were not statistically significant. In the absence of higher level evidence, surgeons should carefully balance risk, cost, and benefits in managing contaminated ventral hernia repair. Copyright © 2016 Elsevier Inc. All rights reserved.

Assessing clustering strategies for Gaussian mixture filtering a subsurface contaminant model

KAUST Repository

Liu, Bo

2016-02-03

An ensemble-based Gaussian mixture (GM) filtering framework is studied in this paper in term of its dependence on the choice of the clustering method to construct the GM. In this approach, a number of particles sampled from the posterior distribution are first integrated forward with the dynamical model for forecasting. A GM representation of the forecast distribution is then constructed from the forecast particles. Once an observation becomes available, the forecast GM is updated according to Bayes’ rule. This leads to (i) a Kalman filter-like update of the particles, and (ii) a Particle filter-like update of their weights, generalizing the ensemble Kalman filter update to non-Gaussian distributions. We focus on investigating the impact of the clustering strategy on the behavior of the filter. Three different clustering methods for constructing the prior GM are considered: (i) a standard kernel density estimation, (ii) clustering with a specified mixture component size, and (iii) adaptive clustering (with a variable GM size). Numerical experiments are performed using a two-dimensional reactive contaminant transport model in which the contaminant concentration and the heterogenous hydraulic conductivity fields are estimated within a confined aquifer using solute concentration data. The experimental results suggest that the performance of the GM filter is sensitive to the choice of the GM model. In particular, increasing the size of the GM does not necessarily result in improved performances. In this respect, the best results are obtained with the proposed adaptive clustering scheme.

Geophysics Based Contaminant Mass Discharge Quantification Downgradient of a Landfill and a Former Pharmaceutical Factory

DEFF Research Database (Denmark)

Balbarini, Nicola; Rønde, Vinni Kampman; Maurya, Pradip

2018-01-01

Contaminant mass discharge is a commonly applied tool to evaluate the environmental impact of contaminated sites on water resources. At large contaminated sites with heterogeneous sources, such as landfills, the number of wells available is often not sufficient, leading to a high uncertainty...... of mass discharge estimates. In this study, we tackle the uncertainty of the contaminant mass discharge due to low sampling densities by interpolating limited water‐sample data with the support of surface Direct Current resistivity and Induced Polarization geophysical data. The method relies on finding...... a conceptual link between the bulk conductivity imaged from geophysics and the contaminant concentrations. We investigate the link between: 1) imaged bulk and electrical water conductivity, 2) water conductivity and conservative ionic species, 3) water conductivity and redox‐sensitive species, 4) water...

Impact of contamination on hydrogenated amorphous silicon thin films and solar cells

Energy Technology Data Exchange (ETDEWEB)

Woerdenweber, Jan

2011-09-26

This thesis deals with atmospheric contamination and cross-contamination of boron (single-chamber process) of the intrinsic absorber layer (i-layer) of p-i-n thin film solar cells based on hydrogenated amorphous silicon. The atmospheric contaminations were introduced by means of intentional leaks. Hereby, the focus is on the influence of contamination species (oxygen and nitrogen), quantity of contamination (leak flow), source of contamination (leaks at chamber wall or in the process gas pipe), and plasma power on the properties of solar cells. Thereby, the minimum requirements for the purity of vacuum and process gas as well as leak conditions of the recipient and gas pipe system have been determined. Additionally, deposition regimes were developed, where the incorporation of impurities is significantly suppressed. For standard processes critical levels of nitrogen and oxygen contamination are determined to be {proportional_to} 4 x 10{sup 18} cm{sup -3} and {proportional_to} 2 x 10{sup 19} cm{sup -3}, respectively, for a leak situated at the chamber wall. Above these concentrations the solar cell efficiency deteriorates. In literature, incorporation of oxygen and nitrogen in doping configuration is assumed to be the reason for the cell deterioration. This assumption is supported by additional material studies of contaminated absorber layers done in this work. The difference in critical concentration is due to the higher doping efficiency of nitrogen compared to that for oxygen. Nevertheless, applying an air leak the critical concentrations of O and N are reached almost simultaneously since the incorporation probability of oxygen is about one order of magnitude higher compared to that for nitrogen. Applying a leak in the process gas pipe the critical oxygen contamination level increases to {proportional_to} 2 x 10{sup 20} cm{sup -3} whereas the critical nitrogen level remains unchanged compared to a chamber wall leak. Applying a deposition regime with a very high

Effects of the proposed EPA groundwater standards on the Uranium Mill Tailings Remedial Action Project

International Nuclear Information System (INIS)

Titus, F.B.

1988-01-01

Potential groundwater contamination beneath the 24 tailings piles that are to be stabilized under the UMTRA Project was intended in early project plans to be minimized by placing disposal piles over thick stratigraphic sequences of tight (minimally permeable) formations, and by designing covers that contained low permeability soil/clay infiltration barriers. The court-ordered revision of the UMTRA groundwater standards by EPA (proposed standards of September 1987) include very low Maximum Concentration Limits (MCLs), which are based mostly on Primary Drinking Water Standards. EPA also mandates that the designs should control radioactivity and hazardous constituents...for up to one thousand years, to the extends reasonably achievable, and, in any case, for at least two hundred years.... In order to accommodate this stipulation, transport modeling of water and contaminants in both the vadose and saturated zones beneath the piles is run until steady state conditions are reached. The early decision to locate stabilized piles over tight formations now exacerbates the problem of complying with the standards, since the contaminants percolate to groundwater that moves only slowly through strata having low permeabilities. Innovative solutions have been evaluated that are aimed at further minimizing long-term infiltration, geochemically fixing contaminants in place before they reach groundwater, or otherwise minimizing contaminant flux

Toxicological benchmarks for screening potential contaminants of concern for effects on terrestrial plants: 1994 revision

International Nuclear Information System (INIS)

Will, M.E.; Suter, G.W. II.

1994-09-01

One of the initial stages in ecological risk assessment for hazardous waste sites is screening contaminants to determine which of them are worthy of further consideration as contaminants of potential concern. This process is termed contaminant screening. It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 38 chemicals potentially associated with United States Department of Energy (DOE) sites. In addition, background information on the phytotoxicity and occurrence of the chemicals in soils is presented, and literature describing the experiments from which data were drawn for benchmark derivation is reviewed. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern

Toxicological benchmarks for screening potential contaminants of concern for effects on terrestrial plants: 1994 revision

Energy Technology Data Exchange (ETDEWEB)

Will, M.E.; Suter, G.W. II

1994-09-01

One of the initial stages in ecological risk assessment for hazardous waste sites is screening contaminants to determine which of them are worthy of further consideration as contaminants of potential concern. This process is termed contaminant screening. It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 38 chemicals potentially associated with United States Department of Energy (DOE) sites. In addition, background information on the phytotoxicity and occurrence of the chemicals in soils is presented, and literature describing the experiments from which data were drawn for benchmark derivation is reviewed. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern.

Insulator Contamination Forecasting Based on Fractal Analysis of Leakage Current

Directory of Open Access Journals (Sweden)

Bing Luo

2012-07-01

Full Text Available In this paper, an artificial pollution test is carried out to study the leakage current of porcelain insulators. Fractal theory is adopted to extract the characteristics hidden in leakage current waveforms. Fractal dimensions of the leakage current for the security, forecast and danger zones are analyzed under four types of degrees of contamination. The mean value and the standard deviation of the fractal dimension in the forecast zone are calculated to characterize the differences. The analysis reveals large differences in the fractal dimension of leakage current under different contamination discharge stages and degrees. The experimental and calculation results suggest that the fractal dimension of a leakage current waveform can be used as a new indicator of the discharge process and contamination degree of insulators. The results provide new methods and valid indicators for forecasting contamination flashovers.

Satellite Contamination and Materials Outgassing Knowledge base

Science.gov (United States)

Minor, Jody L.; Kauffman, William J. (Technical Monitor)

2001-01-01

Satellite contamination continues to be a design problem that engineers must take into account when developing new satellites. To help with this issue, NASA's Space Environments and Effects (SEE) Program funded the development of the Satellite Contamination and Materials Outgassing Knowledge base. This engineering tool brings together in one location information about the outgassing properties of aerospace materials based upon ground-testing data, the effects of outgassing that has been observed during flight and measurements of the contamination environment by on-orbit instruments. The knowledge base contains information using the ASTM Standard E- 1559 and also consolidates data from missions using quartz-crystal microbalances (QCM's). The data contained in the knowledge base was shared with NASA by government agencies and industry in the US and international space agencies as well. The term 'knowledgebase' was used because so much information and capability was brought together in one comprehensive engineering design tool. It is the SEE Program's intent to continually add additional material contamination data as it becomes available - creating a dynamic tool whose value to the user is ever increasing. The SEE Program firmly believes that NASA, and ultimately the entire contamination user community, will greatly benefit from this new engineering tool and highly encourages the community to not only use the tool but add data to it as well.

Air Contamination Quantification by FTIR with Gas Cell

Science.gov (United States)

Freischlag, Jason

2017-01-01

Air quality is of utmost importance in environmental studies and has many industrial applications such as aviators grade breathing oxygen (ABO) for pilots and breathing air for fire fighters. Contamination is a major concern for these industries as identified in MIL-PRF-27210, CGA G-4.3, CGA G-7.1, and NFPA 1989. Fourier Transform Infrared Spectroscopy (FTIR) is a powerful tool that when combined with a gas cell has tremendous potential for gas contamination analysis. Current procedures focus mostly on GC-MS for contamination quantification. Introduction of this topic will be done through a comparison of the currently used deterministic methods for gas contamination with those of FTIR gas analysis. Certification of the mentioned standards through the ISOIEC 17065 certifying body A2LA will be addressed followed by an evaluation of quality information such as the determinations of linearity and the limits of detection and quantitation. Major interferences and issues arising from the use of the FTIR for accredited work with ABO and breathing air will be covered.

Predictors of Heavy Stethoscope Contamination Following a Physical Examination.

Science.gov (United States)

Tschopp, Clément; Schneider, Alexis; Longtin, Yves; Renzi, Gesuele; Schrenzel, Jacques; Pittet, Didier

2016-06-01

BACKGROUND The degree of bacterial contamination of stethoscopes can vary significantly following a physical examination. OBJECTIVE To conduct a prospective study to investigate the impact of various environmental and patient characteristics on stethoscope contamination. METHODS Following a standardized examination, the levels of bacterial contamination of 4 regions of the physicians' hands and 2 sections of the stethoscopes, and the presence of different pathogenic bacteria, were assessed. Predictors of heavy stethoscope contamination were identified through multivariate logistic regression. RESULTS In total, 392 surfaces were sampled following examination of 56 patients. The microorganisms most frequently recovered from hands and stethoscopes were Enterococcus spp. (29% and 20%, respectively) and Enterobacteriaceae (16% and 7%, respectively). Staphylococcus aureus (either methicillin susceptible or resistant), extended-spectrum β-lactamase-producing Enterobacteriaceae, and Acinetobacter baumannii were recovered from 4%-9% of the samples from either hands or stethoscopes. There was a correlation between the likelihood of recovering these pathogens from the stethoscopes vs from the physicians' hands (ρ=0.79; P=.04). The level of patient's skin contamination was an independent predictor of contamination of the stethoscope diaphragm (adjusted odds ratio [aOR], 1.001; P=.007) and tube (aOR, 1.001; P=.003). Male sex (aOR, 28.24; P=.01) and reception of a bed bath (aOR, 7.52; P=.048) were also independently associated with heavy tube contamination. CONCLUSIONS Stethoscope contamination following a single physical examination is not negligible and is associated with the level of contamination of the patient's skin. Prevention of pathogen dissemination is needed. Infect Control Hosp Epidemiol 2016;37:673-679.

106-17 Telemetry Standards Front Matter

Science.gov (United States)

2017-07-01

Frequency Division Multiplexing Telemetry Standards CHAPTER 4: Pulse Code Modulation Standards CHAPTER 5: Digitized Audio Telemetry Standard CHAPTER 6...Transfer Standard Chapter 9, Appendix 9-A Appendix I, Telemetry Attributes Transfer Standard Cover Sheet Chapter 9, Appendix 9-B Telemetry Standards...Derived Parameter Specification Chapter 9, Appendix 9-E Appendix Q, Extended Binary Golay Code Chapter 7, Appendix 7-A Appendix R, Low-Density Parity

Optimization of fodder rations for intensive development of cattle-breeding in an radioactive contaminated zone

International Nuclear Information System (INIS)

Stolyarov, G.V.

1999-01-01

It has been calculated some variants of the optimal structure of milk cow herd's fodder rations in a radioactive contaminated zone in dependence of the contamination density. Rations were balanced in primary nutritive including digestible protein. It has been determined their costs and specific radioactivity of cesium-137. These fodder rations can be recommended to the farms of the Gomel Region suffered from the Chernobyl nuclear power station explosion

Resistivity and self-potential tomography applied to groundwater remediation and contaminant plumes: Sandbox and field experiments

Science.gov (United States)

Mao, D.; Revil, A.; Hort, R. D.; Munakata-Marr, J.; Atekwana, E. A.; Kulessa, B.

2015-11-01

Geophysical methods can be used to remotely characterize contaminated sites and monitor in situ enhanced remediation processes. We have conducted one sandbox experiment and one contaminated field investigation to show the robustness of electrical resistivity tomography and self-potential (SP) tomography for these applications. In the sandbox experiment, we injected permanganate in a trichloroethylene (TCE)-contaminated environment under a constant hydraulic gradient. Inverted resistivity tomograms are able to track the evolution of the permanganate plume in agreement with visual observations made on the side of the tank. Self-potential measurements were also performed at the surface of the sandbox using non-polarizing Ag-AgCl electrodes. These data were inverted to obtain the source density distribution with and without the resistivity information. A compact horizontal dipole source located at the front of the plume was obtained from the inversion of these self-potential data. This current dipole may be related to the redox reaction occurring between TCE and permanganate and the strong concentration gradient at the front of the plume. We demonstrate that time-lapse self-potential signals can be used to track the kinetics of an advecting oxidizer plume with acceptable accuracy and, if needed, in real time, but are unable to completely resolve the shape of the plume. In the field investigation, a 3D resistivity tomography is used to characterize an organic contaminant plume (resistive domain) and an overlying zone of solid waste materials (conductive domain). After removing the influence of the streaming potential, the identified source current density had a magnitude of 0.5 A m-2. The strong source current density may be attributed to charge movement between the neighboring zones that encourage abiotic and microbially enhanced reduction and oxidation reactions. In both cases, the self-potential source current density is located in the area of strong resistivity

Small Bandwidth Asymptotics for Density-Weighted Average Derivatives

DEFF Research Database (Denmark)

Cattaneo, Matias D.; Crump, Richard K.; Jansson, Michael

This paper proposes (apparently) novel standard error formulas for the density-weighted average derivative estimator of Powell, Stock, and Stoker (1989). Asymptotic validity of the standard errors developed in this paper does not require the use of higher-order kernels and the standard errors...

Development of a personalized dosimetric tool for radiation protection in case of internal contamination and targeted radiotherapy in nuclear medicine

International Nuclear Information System (INIS)

Chiavassa, S.

2005-12-01

Current internal dosimetric estimations are based on the M.I.R.D. formalism and used standard mathematical models. These standard models are often far from a given patient morphology and do not allow to perform patient-specific dosimetry. The aim of this study was to develop a personalized dosimetric tool, which takes into account real patient morphology, composition and densities. This tool, called O.E.D.I.P.E., a French acronym of Tool for the Evaluation of Personalized Internal Dose, is a user-friendly graphical interface. O.E.D.I.P.E. allows to create voxel-based patient-specific geometries and associates them with the M.C.N.P.X. Monte Carlo code. Radionuclide distribution and absorbed dose calculation can be performed at the organ and voxel scale. O.E.D.I.P.E. can be used in nuclear medicine for targeted radiotherapy and in radiation protection in case of internal contamination. (author)

Density Distributions of Cyclotrimethylenetrinitramines (RDX)

International Nuclear Information System (INIS)

Hoffman, D M

2002-01-01

As part of the US Army Foreign Comparative Testing (FCT) program the density distributions of six samples of class 1 RDX were measured using the density gradient technique. This technique was used in an attempt to distinguish between RDX crystallized by a French manufacturer (designated insensitive or IRDX) from RDX manufactured at Holston Army Ammunition Plant (HAAP), the current source of RDX for Department of Defense (DoD). Two samples from different lots of French IRDX had an average density of 1.7958 ± 0.0008 g/cc. The theoretical density of a perfect RDX crystal is 1.806 g/cc. This yields 99.43% of the theoretical maximum density (TMD). For two HAAP RDX lots the average density was 1.786 ± 0.002 g/cc, only 98.89% TMD. Several other techniques were used for preliminary characterization of one lot of French IRDX and two lot of HAAP RDX. Light scattering, SEM and polarized optical microscopy (POM) showed that SNPE and Holston RDX had the appropriate particle size distribution for Class 1 RDX. High performance liquid chromatography showed quantities of HMX in HAAP RDX. French IRDX also showed a 1.1 C higher melting point compared to HAAP RDX in the differential scanning calorimetry (DSC) consistent with no melting point depression due to the HMX contaminant. A second part of the program involved characterization of Holston RDX recrystallized using the French process. After reprocessing the average density of the Holston RDX was increased to 1.7907 g/cc. Apparently HMX in RDX can act as a nucleating agent in the French RDX recrystallization process. The French IRDX contained no HMX, which is assumed to account for its higher density and narrower density distribution. Reprocessing of RDX from Holston improved the average density compared to the original Holston RDX, but the resulting HIRDX was not as dense as the original French IRDX. Recrystallized Holston IRDX crystals were much larger (3-500 (micro)m or more) then either the original class 1 HAAP RDX or French

Laboratory Evaluation of Light Obscuration Particle Counter Contamination Limits for Aviation Fuel

Science.gov (United States)

2015-11-01

assurance testing though conducting periodic fuel sampling for gravimetric analysis. The Army currently utilizes two methods for measuring particulate...contamination by gravimetric analysis: ASTM D2276 - Standard Test Method for Particulate Contaminant in Aviation Fuel by Line Sampling, and ASTM D5452...while filter effectiveness is checked every 30 days by gravimetric analysis (ASTM D2276). One of the problems with the gravimetric methods is the

Nitrification and nitrogen mineralization in agricultural soils contaminated by copper mining activities in Central Chile

OpenAIRE

Moya, Héctor; Verdejo, José; Yáñez, Carolina; Álvaro, Juan E.; Sauvé, Sébastien; Neaman, Alexander

2017-01-01

Microbiological bioassays of nitrification and nitrogen mineralization have been used for evaluation of soil quality on metal-contaminated soils. We evaluated the effectiveness of nitrification and nitrogen mineralization bioassays as quality indicators of soil degradation caused by metal contamination. We performed standard tests based on protocols of ISO 14238 (2012) and ISO 15685 (2012) on 90 soil samples collected from agricultural areas in central Chile that were historically contaminate...

Statistical considerations in practical contamination monitoring

International Nuclear Information System (INIS)

Brodsky, A.; Gallaghar, R.G.

1991-01-01

This paper reports on an examination of smear survey practices which indicates that many radiation safety programs are lacking in important aspects of contamination monitoring. In order to satisfy regulatory and potential litigatory requirements, smear surveys should include the measurement and recording of the flowing data: area of each smear and smear procedure (by reference); total counts on smear and counting procedure; total counts on appropriate blanks and description of blank; total counts on standard and specifications of standard; and all counting times. The rationale for these smear survey requirements is obtained by examining the formulation of the minimum detectable amount (MDA) on a smear

HFS-II hands and feet contamination monitor for α, β

International Nuclear Information System (INIS)

Du Xiangyang; Han Shuping; Wang Xiaodong; Fan Liya; Zhang Yong; Rao Xianming; Fang Jintu

1999-11-01

HFS-II Hands and Feet Contamination Monitor for α, β is a necessary device which monitors the entrance of controlling area of nuclear power plant and nuclear facility, and it consists of nuclear detector, nuclear electronic circuit, computer data processing and controlling divisions, input/output controlling etc. Physical indicators conform to the requirements of relative national standard GB8703-87 and department standard EJ/T586

Activities of HPS standards committee in environmental remediation

International Nuclear Information System (INIS)

Stencel, J.R.

1994-01-01

The Health Physics Society (HPS) develops American National Standards in the area of radiation protection using methods approved by the American National Standards Institute (ANSI). Two of its sections, Environmental Health Physics and Contamination Limits, have ongoing standards development which are important to some environmental remediation efforts. This paper describes the role of the HPS standards process and indicates particular standards under development which will be of interest to the reader. In addition, the authors solicit readers to participate in the voluntary standards process by either joining active working groups (WG) or suggesting appropriate and relevant topics which should be placed into the standards process

Remediation of contamination from radioactive material by the Fukushima Dai-ichi Nuclear Power Plant accident

International Nuclear Information System (INIS)

Inoue, Tadashi; Takahashi, Fumiaki; Morokuzu, Muneo

2011-01-01

The information on the environmental remediation of regional contamination in Chernobyl disaster is mentioned. The contaminated trash cannot be treated as an industrial waste on the legislation. There is no safety standard on the release of refuge. These arrangement on the legislation has been needed. (M.H.)

Transport of Aquatic Contaminant and Assessment of Radioecological Exposure with Spatial and Temporal Effects

Science.gov (United States)

Feng, Ying

1995-01-01

A comprehensive study of the radioecological exposure assessment for a contaminated aquatic ecosystem has been performed in this dissertation. The primary objectives of this research were to advance the understanding of radiation exposure in nature and to increase current capabilities for estimating aquatic radiation exposure with the consideration of spatial and temporal effect in nature. This was accomplished through the development of a two-dimensional aquatic exposure assessment framework and by applying the framework to the contaminated Chernobyl cooling lake (pond). This framework integrated spatial and temporal heterogeneity effects of contaminant concentration, abundance and distribution of ecosystem populations, spatial- and temporal-dependent (or density-dependent) radionuclide ingestion, and alternative food web structures. The exposure model was built on the population level to allow for the integration of density dependent population regulation into the exposure assessment. Plankton population dynamics have been integrated into the hydrodynamic-transport model to determine plankton biomass density changes and distributions. The distribution of contaminant in water was also calculated using a hydrodynamic-transport model. The significance of adding spatial and temporal effects, spatial and temporal related ecological functions, and hydrodynamics in the exposure assessment was illustrated through a series of case studies. The results suggested that the spatial and temporal heterogeneity effects of radioactive environments were substantial. Among the ecological functions considered, the food web structure was the most important contributor to the variations of fish exposure. The results obtained using a multiple prey food web structure differed by a factor of 20 from the equilibrium concentration, and by a factor of 2.5 from the concentration obtained using a single-prey food web. Impacts of changes in abundance and distribution of biomass on contaminant

Organization of internal contamination monitoring

International Nuclear Information System (INIS)

Badreddine, A.

1986-07-01

The nuclear energy takes a big part in the world's energy production. The nuclear techniques are used in most fields of life. Nevertheless the use of radioactive materials may cause prejudice to human beings by radiation contamination. The International Commission on Radiological Protection gives the general rules and regulations to avoid this danger. In the publication No. 30, the ICRP gives a metabolic model for the respiratory system and values of Annual Limit of Intake. The ALI for inhalation supposes a standard AMAD (Activity Median Aerodynamic Diameter) of 1 um. We have measured the AMAD in a laboratory under different conditions of functioning in order to show its variation. Then we have analysed the effect of this variation on the internal contamination monitoring. Thus we have calculated the Effective Committed Dose (ECD), the ALI, then the Derived Investigation Level (DIL) for different values of AMAD for Whole-Body Counting (WBC)

Survey of radioactive contamination for foodstuffs

International Nuclear Information System (INIS)

Lee, Wan No; Lee, Chang Wu; Choi, Geun Sik; Cho, Yeong Hyeon; Kang, Mun Ja; Cheong, Geun Ho; Kim, Hui Ryeong; Park, Du Won; Park, Hyo Guk; Kwak, Ji Yeon

2006-11-01

After the Chernobyl nuclear accident in 1986, a lot of countries including EU, Japan, USA are to strengthen survey of radioactive contamination for foodstuffs. Our country has also surveyed radioactive contamination of the imported foodstuffs and started to check continuously the radioactivity contamination of the open market foodstuffs since 2003. In this year, imported foodstuffs(130 samples) and domestic foodstuffs(10 samples) are analyzed to investigate the radioactive contamination. Sampled foodstuffs items are collected from the open markets; one group is the imported foodstuffs and the other group is the domestic foodstuffs producted around nuclear facilities and northeast of Sokcho city concerning recent situations. Samples are usually bought from traditional markets, mart, department store or the Internet. After pretreatments such as drying, ashing, and homogenization, all samples were analyzed by gamma spectrometer system for survey and assessment of radioactive contamination. The 131 I radionuclide isn't detected among all foodstuffs(imported and domestic). The 137 Cs radionuclide among the regulation radionuclides( 137 Cs, 13 4 C s, 131 I) of food code is only detected at the imported foodstuffs but its level is far below the maximum permitted level. For the improvement of measurement confidence, the developed analysis method is tested by the participation of the national and international intercomparison. The developed method based on test results and international standard would be used at radioactive analysis as well as an education of relative workers. It could be applied as the basis data for amending the analysis method of food code. It is technically supported for radioactive analysis of commercial company and the government including KFDA. Finally these results would be used to solve an ambiguous anxiety of a people for radiation exposure by foodstuffs intake and help the KFDA to manage systematically the radioactive contamination and to give

A robust standard deviation control chart

NARCIS (Netherlands)

Schoonhoven, M.; Does, R.J.M.M.

2012-01-01

This article studies the robustness of Phase I estimators for the standard deviation control chart. A Phase I estimator should be efficient in the absence of contaminations and resistant to disturbances. Most of the robust estimators proposed in the literature are robust against either diffuse

Natural matrix standards

International Nuclear Information System (INIS)

Bowen, V.T.

1976-01-01

Environmental radiochemistry needs, for use in analytical intercomparision and as standard reference materials, very large homogeneous samples of a variety of matrices, each naturally contaminated by a variety of longer-lived radionuclides, at several different ranges of concentrations. The reasons for this need are discussed, and the minimum assortment of matrices of radionuclides, and of concentrations is established. Sources of suitable materials are suggested, and the international approach to meeting this need is emphasized

Interrelationships among geotechnical and leaching properties of a cement-stabilized contaminated soil.

Science.gov (United States)

Kogbara, Reginald B

2017-01-28

Relationships among selected performance properties have been established using experimental data from a cement-stabilized mixed contaminated soil. The sandy soil was spiked with 3,000 mg/kg each of Cd, Cu, Pb, Ni and Zn, and 10,000 mg/kg of diesel. It was then treated with 5%, 10%, 15%, and 20% dosages of Portland cement. Different water contents were considered for lower dosage mixes. Selected geotechnical and leaching properties were determined on 28-day old samples. These include unconfined compressive strength (UCS), bulk density, porosity, hydraulic conductivity, leachate pH and granular leachability of contaminants. Interrelationships among these properties were deduced using the most reasonable best fits determined by specialized curve fitting software. Strong quadratic and log-linear relationships exist between hydraulic conductivity and UCS, with increasing binder and water contents, respectively. However, the strength of interrelationships between hydraulic conductivity and porosity, UCS and porosity, and UCS and bulk density varies with binder and water contents. Leachate pH and granular leachability of contaminants are best related to UCS and hydraulic conductivity by a power law and an exponential function, respectively. These results suggest how the accuracy of not-easily-measurable performance properties may be constrained from simpler ones. Comparisons with some published performance properties data support this.

Impurity screening in high density plasmas in tokamaks with a limiter configuration

International Nuclear Information System (INIS)

Ferro, C.; Zanino, R.

1992-01-01

Impurity screening in high density plasmas in tokamaks with a limiter configuration is investigated by means of a simple semi-analytical model. An iterative scheme is devised, in order to determine self-consistently the values of scrape-off layer thickness, edge electron density and temperature, and main plasma contamination parameter Z eff , as a function of given average electron density and temperature in the main plasma and given input power. The model is applied to the poloidal limiter case of the Frascati Tokamak Upgrade, and results are compared with experimental data. A reasonable agreement between the trends is found, emphasizing the importance of a high edge plasma density for obtaining a clean main plasma in limiter tokamaks. (orig.)

Field surveying of radionuclide contamination in forests

International Nuclear Information System (INIS)

Turunen, J.; Rantavaara, A.; Ammann, M.

2009-01-01

Field measurements of radionuclides after an accidental contamination of forests assume the capacity for identification of a number of nuclides in varying source geometries. The continuous redistribution of radionuclides in forests through natural processes implies a decrease of prevailing surface contamination of trees and an increase in activity density on the ground. Portable gamma spectrometers have long been based on Na(I) detectors which, due to their low energy resolution, are not the tool for analysis of contamination from accidental releases of fission and activation products in the first days or weeks after a deposition. Data of airborne radionuclides from the Chernobyl accident in April 1986 were used for demonstration of initial and later distribution of radionuclides as sources of air Kerma in forests. Forest model (FDMF, PV. 6.0) of the RODOS system was used for the assessment of time-dependent Kerma rate from different forest compartments. The results show the fast reduction of activities of short-lived nuclides and their contributions to the Kerma rate in the first weeks and months. The results also give an estimate for the time needed until a gamma spectrometer with a low energy resolution would give useful information about long-lived radioactivity on the forest floor. An example is given on a portable high resolution semiconductor spectrometer that has suitable characteristics for field surveying also during occurrence of a great number of radionuclides contributing to the gamma spectrum. The needs for further research of a recently deposited radionuclide contamination on forest vegetation and soil, and the efforts for improvement of portable radiation meters and their use in management planning and radioecological research on contaminated forests are discussed. (au)

Performance of Vetiver Grass (Vetiveria zizanioides for Phytoremediation of Contaminated Water

Directory of Open Access Journals (Sweden)

Syed Hasan Sharifah Nur Munirah

2017-01-01

Full Text Available In tolerance towards metal uptake, there is a need to evaluate the performance of vetiver grass for metal removal to reduce water impurity. This study was aimed to evaluate contaminant removal by vetiver grass at varying root length and plant density and determine the metal uptake in vetiver plant biomass. Pollutant uptake of vetiver grass was conducted in laboratory experiment and heavy metal analysis was done using acid digestion and Atomic Absorption Spectrometry. Findings indicated that the removal of heavy metal was decreased in seven days of the experiment where iron shows the highest percentage (96%; 0.42 ppm of removal due to iron is highly required for growth of vetiver grass. Removal rate of heavy metals in water by vetiver grass is ranked in the order of Fe>Zn>Pb>Mn>Cu. Results also demonstrated greater removal of heavy metals (Cu, Fe, Mn, Pb, Zn at greater root length and higher density of vetiver grass because it increased the surface area for metal absorption by plant root into vetiver plant from contaminated water. However, findings indicated that accumulation of heavy metals in plant biomass was higher in vetiver shoot than in root due to metal translocation from root to the shoot. Therefore, the findings have shown effective performance of vetiver grass for metal removal in the phytoremediation of contaminated water.

Implementation of GIS-DSS PRANA within sustainable rehabilitation of radioactive contaminated territories

International Nuclear Information System (INIS)

Yatsalo, B.

2003-01-01

Full text: Analysis of the current situation in contaminated farms and settlements of Bryansk region is based on the monitoring data and model estimates. Model assessments of agricultural produce contamination, doses to the local population, radiological risk and results of countermeasure (CM) implementation have been carried out with the use of PRANA GIS-DSS. Applied Geographic Information System (GIS) PRANA is a Decision Support System (DSS) for implementation within the rehabilitation of radioactive contaminated territories. PRANA has been introduced for practical use in Bryansk as a GIS-DSS system for monitoring networking support and countermeasure analysis. The main blocks of the PRANA DSS are: libraries of electronic maps, including different layers of vector maps of landuse for all contaminated districts of Bryansk region: Novozybkov, Klintsy, Gordeevsky, Krasnogorsky, Zlynkovsky and Klimovsky (more than 30000 polygons of vector electronic maps); databases (radioecological, ecological, economic, demographic and other monitoring data and model parameters, including attributive information of vector electronic maps); model blocks for assessing: contamination of agricultural production, external and internal doses to the local population, radiological risks and corresponding results of CMs implementation; evaluation of CMs effectiveness and decision-making support an protection of the population and rehabilitation of radioactive contaminated territories both on local and regional/district levels (from separate settlement/field up to group of settlements/farms and region as a whole). The following 'risk indices' are considered within decision-making an Risk Based Land Management (RBLM) with the use of PRANA DSS: surface density contamination of territory with radionuclides ( 137 Cs, 90 Sr); contamination of agricultural production (plant growing and animal husbandry, including farm and private production); external and internal doses to the local population

Nanofiltration vs. reverse osmosis for the removal of emerging organic contaminants in water reuse

KAUST Repository

Yangali-Quintanilla, Victor

2011-10-01

Reverse osmosis (RO) in existing water reuse facilities is a water industry standard. However, that approach may be questioned taking into consideration that "tight" NF can be equal or "better" than RO. NF can achieve the same removals of RO membranes when dealing with emerging organic contaminants (pharmaceuticals, pesticides, endocrine disruptors and others). Experiments using 18 emerging contaminants were performed using membranes NF200 and NF90 at bench-scale units, and for a more complete study, results of NF and RO pilot and full-scale experiments where compared to our experimental results. The removal results showed that NF can remove many emerging contaminants. The average removal by tight NF was 82% for neutral contaminants and 97% for ionic contaminants. The average removal by RO was 85% for neutral contaminants and 99% for ionic contaminants. Aquifer recharge and recovery (ARR) followed by NF can effectively remove emerging contaminants with removals over 90% when loose NF membranes are used.

Nanofiltration vs. reverse osmosis for the removal of emerging organic contaminants in water reuse

KAUST Repository

Yangali-Quintanilla, Victor

2011-01-01

Reverse osmosis (RO) in existing water reuse facilities is a water industry standard. However, that approach may be questioned taking into consideration that "tight" NF can be equal or "better" than RO. NF can achieve the same removals of RO membranes when dealing with emerging organic contaminants (pharmaceuticals, pesticides, endocrine disruptors and others). Experiments using 18 emerging contaminants were performed using membranes NF200 and NF90 at bench-scale units, and for a more complete study, results of NF and RO pilot and fullscale experiments where compared to our experimental results. The removal results showed that NF can remove many emerging contaminants. The average removal by tight NF was 82% for neutral contaminants and 97% for ionic contaminants. The average removal by RO was 85% for neutral contaminants and 99% for ionic contaminants. Aquifer recharge and recovery (ARR) followed by NF can effectively remove emerging contaminants with removals over 90% when loose NF membranes are used. © 2011 2011 Desalination Publications. All rights reserved.

Problems in assessing the risks of mixtures of contaminants in drinking water

International Nuclear Information System (INIS)

Vanderslice, R.R.; Orme, J.; Ohanian, E.V.; Sonich-Mullin, C.

1989-01-01

In conducting risk assessments on drinking water contaminants, the U.S. Environmental Protection Agency (EPA) attempts to evaluate all available toxicity data to develop Health Advisory (HA) and Maximum Contaminant Level Goal (MCLG) values. The EPA often has grappled with the issues surrounding the toxicity of chemical mixtures, including radioactive contaminants, nitrate/nitrite, and trihalomethanes (THMs). In evaluating the toxicity of chemical mixtures, the EPA's immediate concern is whether the individual HA values and MCLGs are protecting public health when multiple contaminants are present in drinking water. Potential toxic interactions between drinking water contaminants are difficult to predict because experimental studies are generally performed only at high doses relative to environmental levels. Although the contamination of drinking water involves mixtures of contaminants, drinking water regulations are generally based on an assessment of the risks of individual contaminants. This paper discusses three issues of major concern to the EPA: the synergistic effects of solvent mixtures, vehicle effects in laboratory studies, and setting standards for essential trace nutrients where the absorption and/or toxicity are affected by an individual's nutritional status or other dietary components. 12 references

Listeria monocytogenes contamination in dairy plants: evaluation of Listeria monocytogenes environmental contamination in two cheese-making plants using sheeps milk

Directory of Open Access Journals (Sweden)

Michela Ibba

2013-09-01

Full Text Available Listeria monocytogenes harbouring niches established in the processing plant support post-process contamination of dairy products made from pasteurised or thermised milk. The present study investigated L. monocytogenes environmental contamination in two sheep’s milk cheese-making plants. Persistence of contamination in the area at higher risk was also investigated. During a one-year survey 7 samplings were carried out in each dairy plant, along the production lines of Pecorino Romano and ricotta salata cheese. A total of 613 environmental samples collected from food contact and non-food contact surfaces were analysed according to ISO 11290-1:2005 standard method. Identification of the isolated strains was carried out by polymerase chain reaction. L. monocytogenes prevalence was 23.2% in dairy A and 13.1% in dairy B, respectively. The higher prevalence rate was found in the following areas: salting, products washing, packaging, ricotta salata storage and Pecorino Romano ripening rooms. L. monocytogenes was never found in the cheese-making area. The probability of observing samples positive for the presence of L. monocytogenes was asso- ciated with dairy plant, sampling area and the period of cheese-making (P<0.001. The greater persistence of contamination over time was observed in the washing, salting, and Pecorino Romano ripening areas. The control of persistent environmental contamination relies on the identification of L. monocytogenes niches within the processing environment and the prevention of harborage sites formation. The importance of strict cleaning and sanitising procedure in controlling L. monocytogenes environmental contamination is confirmed by the lower level of contamination observed after these procedures were correctly implemented.

Redox potential distribution of an organic-rich contaminated site obtained by the inversion of self-potential data

Science.gov (United States)

Abbas, M.; Jardani, A.; Soueid Ahmed, A.; Revil, A.; Brigaud, L.; Bégassat, Ph.; Dupont, J. P.

2017-11-01

Mapping the redox potential of shallow aquifers impacted by hydrocarbon contaminant plumes is important for the characterization and remediation of such contaminated sites. The redox potential of groundwater is indicative of the biodegradation of hydrocarbons and is important in delineating the shapes of contaminant plumes. The self-potential method was used to reconstruct the redox potential of groundwater associated with an organic-rich contaminant plume in northern France. The self-potential technique is a passive technique consisting in recording the electrical potential distribution at the surface of the Earth. A self-potential map is essentially the sum of two contributions, one associated with groundwater flow referred to as the electrokinetic component, and one associated with redox potential anomalies referred to as the electroredox component (thermoelectric and diffusion potentials are generally negligible). A groundwater flow model was first used to remove the electrokinetic component from the observed self-potential data. Then, a residual self-potential map was obtained. The source current density generating the residual self-potential signals is assumed to be associated with the position of the water table, an interface characterized by a change in both the electrical conductivity and the redox potential. The source current density was obtained through an inverse problem by minimizing a cost function including a data misfit contribution and a regularizer. This inversion algorithm allows the determination of the vertical and horizontal components of the source current density taking into account the electrical conductivity distribution of the saturated and non-saturated zones obtained independently by electrical resistivity tomography. The redox potential distribution was finally determined from the inverted residual source current density. A redox map was successfully built and the estimated redox potential values correlated well with in

[The dose estimation to the population as a result of radioactive contamination of the Semipalatinsk Test area].

Science.gov (United States)

Spiridonova, S I; Mukusheva, M K; Shubina, O A; Solomatin, V M; Epifanova, I E

2008-01-01

The results are presented from estimation of spatial distribution of 137Cs and 90Sr contamination densities in the areas of horses and sheep grazing within the Semipalatinsk Test Site. Dose burdens to various cohorts of the population living within the STS and consuming contaminated animal products are predicted. Doses of shepherds in the most contaminated pasture areas have been found to exceed the accepted limit (1 mSv/y). The conclusion is made about the need for further studies on the risk assessment of the STS population exposure above the accepted limits.

Regional radiation standards for population of Chelyabinsk region

International Nuclear Information System (INIS)

Kravtsova, Eh.M.; Zajtseva, Yh.A.; Panteleev, V.V.; Gavrilov, A.P.; Kolotygina, N.V.; Pudovkina, L.V.; Kravtsova, O.S.

1996-01-01

Regional radiation regulations for population exposures in Chelyabinsk region are developed which are to play the role of standard limits. The priority goal of setting standard level is to consolidate the achieved radioecological balance on the contaminated territories and to establish a mechanism of control over the activities of the facility and over the use of lands in restriction zone by the population

An Iterative Ensemble Kalman Filter with One-Step-Ahead Smoothing for State-Parameters Estimation of Contaminant Transport Models

KAUST Repository

Gharamti, M. E.; Ait-El-Fquih, Boujemaa; Hoteit, Ibrahim

2015-01-01

Numerical experiments are conducted with a two-dimensional synthetic subsurface transport model simulating the migration of a contaminant plume in a heterogenous aquifer domain. Contaminant concentration data are assimilated to estimate both the contaminant state and the hydraulic conductivity field. Assimilation runs are performed under imperfect modeling conditions and various observational scenarios. Simulation results suggest that the proposed scheme efficiently recovers both the contaminant state and the aquifer conductivity, providing more accurate estimates than the standard Joint and Dual EnKFs in all tested scenarios. Iterating on the update step of the new scheme further enhances the proposed filter’s behavior. In term of computational cost, the new Joint-EnKF is almost equivalent to that of the Dual-EnKF, but requires twice more model integrations than the standard Joint-EnKF.

High-Sensitivity Measurement of Density by Magnetic Levitation.

Science.gov (United States)

Nemiroski, Alex; Kumar, A A; Soh, Siowling; Harburg, Daniel V; Yu, Hai-Dong; Whitesides, George M

2016-03-01

This paper presents methods that use Magnetic Levitation (MagLev) to measure very small differences in density of solid diamagnetic objects suspended in a paramagnetic medium. Previous work in this field has shown that, while it is a convenient method, standard MagLev (i.e., where the direction of magnetization and gravitational force are parallel) cannot resolve differences in density mm) because (i) objects close in density prevent each other from reaching an equilibrium height due to hard contact and excluded volume, and (ii) using weaker magnets or reducing the magnetic susceptibility of the medium destabilizes the magnetic trap. The present work investigates the use of weak magnetic gradients parallel to the faces of the magnets as a means of increasing the sensitivity of MagLev without destabilization. Configuring the MagLev device in a rotated state (i.e., where the direction of magnetization and gravitational force are perpendicular) relative to the standard configuration enables simple measurements along the axes with the highest sensitivity to changes in density. Manipulating the distance of separation between the magnets or the lengths of the magnets (along the axis of measurement) enables the sensitivity to be tuned. These modifications enable an improvement in the resolution up to 100-fold over the standard configuration, and measurements with resolution down to 10(-6) g/cm(3). Three examples of characterizing the small differences in density among samples of materials having ostensibly indistinguishable densities-Nylon spheres, PMMA spheres, and drug spheres-demonstrate the applicability of rotated Maglev to measuring the density of small (0.1-1 mm) objects with high sensitivity. This capability will be useful in materials science, separations, and quality control of manufactured objects.

Long-term strategy of rehabilitation of Byelorussian territories contaminated by radionuclides

International Nuclear Information System (INIS)

Kenik, I.; Rolevich, I.; Gurachevsky, V.; Poplyko, I.; Ageets, V.

1999-01-01

Thus, by applying a combination of countermeasures on various technological stages of agricultural production, one can control the process of production and the use of agricultural products, ensuring the production of major foodstuffs in contaminated regions in quantities sufficient for the population living there and in accordance with the consumption standards, and also corresponding to the standards of ecological and radiation safety. The following works in agriculture will require investment by the state: selection of new varieties of agricultural crops and creation of new technologies; development of seed production in a way allowing to reduce the contamination of the final product with radionuclides; refinement of the maps showing contamination of arable land with 137 Cs and 90 Sr based on the constant monitoring; improvement of pastures and hay fields for the private livestock. The following works are needed to stabilize livestock production and ensure production of clean livestock products in contaminated areas: increase the volume of production for major products made of livestock; equip livestock farms with machinery; improve production of forage at the farms by enhancing the structure of fields sown with forage crops, achieving higher yields, introducing progressive methods of harvesting and storing of forage, introduction of mineral additives and biologically active substances. The realistic assessment of the radioactive situation and its forecast lead to the conclusion that the contaminated territory can be rehabilitated with the help of the combined application of the above mentioned organisational and special measures leading to the reduction of the individual dose to 1 mSv per year. (authors)

First Results from Contamination Monitoring with the WFC3 UVIS G280 Grism

Science.gov (United States)

Rothberg, B.; Pirzkal, N.; Baggett, S.

2011-11-01

The presence of contaminants within the optical light path of the instrument or telescope can alter photometric zeropoints and the observed flux levels of imaging and spectra, particularly at UV wavelengths. Regular monitoring of a spectro-photometric standard star using photometric filters has been used in the past to monitor the presence of contaminants and (when necessary) re-calibrate zeropoints. However, the use of the WFC3 UVIS Grism mode (G280 filter) may provide a more robust early alert detection system for the presence of contaminants, in particular, those that are photo-polymerized from the bright Earth. These contaminants may collect on surfaces in the optical light path of the telescope. The G280 grism is sensitive to light at wavelengths below the cutoff of the bluest UV filter (F218W). In this ISR, we present: 1) the first results from G280 monitoring for the period of 2010-November through 2011-August; 2) the discovery of an anomaly in the WCS header information of sub-array exposures; and 3) an outline for reducing standard G280 grism observations and the specialized case of observations obtained in sub-array mode.

Accurate polynomial expressions for the density and specific volume of seawater using the TEOS-10 standard

Science.gov (United States)

Roquet, F.; Madec, G.; McDougall, Trevor J.; Barker, Paul M.

2015-06-01

A new set of approximations to the standard TEOS-10 equation of state are presented. These follow a polynomial form, making it computationally efficient for use in numerical ocean models. Two versions are provided, the first being a fit of density for Boussinesq ocean models, and the second fitting specific volume which is more suitable for compressible models. Both versions are given as the sum of a vertical reference profile (6th-order polynomial) and an anomaly (52-term polynomial, cubic in pressure), with relative errors of ∼0.1% on the thermal expansion coefficients. A 75-term polynomial expression is also presented for computing specific volume, with a better accuracy than the existing TEOS-10 48-term rational approximation, especially regarding the sound speed, and it is suggested that this expression represents a valuable approximation of the TEOS-10 equation of state for hydrographic data analysis. In the last section, practical aspects about the implementation of TEOS-10 in ocean models are discussed.

The Cosmological Standard Model and Its Implications for Beyond the Standard Model of Particle Physics

CERN Multimedia

CERN. Geneva

2011-01-01

While the cosmological standard model has many notable successes, it assumes 95% of the mass-energy density of the universe is dark and of unknown nature, and there was an early stage of inflationary expansion driven by physics far beyond the range of the particle physics standard model. In the colloquium I will discuss potential particle-physics implications of the standard cosmological model.

Radiation risks to human health during air pollution from wildfires in contaminated zones

International Nuclear Information System (INIS)

Dvornik, A.A.

2016-01-01

The results of the investigation of radiation hazard of forest fires in the radioactive contaminated areas are presented in the article. Airborne concentration of Cs 137 produced by the combustion of forest fuel materials with different contamination density can exceed the permissible activity levels of Cs 137 in air. The emission containing radionuclides deposited on the fine aerosol fractions is particularly dangerous. Inhalation of radionuclides can generate additional internal doses both for fire-fighters, near the source of ignition, and for citizens, at a distance from the source. (authors)

Escherichia coli contamination of babies' food-serving utensils in a district of West Sumatra, Indonesia.

Science.gov (United States)

Kusuma, Aria; Eryando, Tris; Susanna, Dewi

2012-01-01

Contamination of baby's complementary food may occur with Escherichia coli from several sources including unclean utensils. We examined the relationship between socio-economic conditions, environmental factors, characteristics of food handlers and contamination of babies food-serving utensils with E. coli. The study was conducted in 21 villages of the Community Health Centre (CHC) Selayo in Indonesia. A cross-sectional design was used. A sample of 142 households, which had a 6-12 month-old baby on complementary food, was chosen randomly using midwives' registration books. Respondents were interviewed using a semi-structured questionnaire. Check-lists were used for observations. Standard laboratory methods were used for collection of specimen and confirmation of contamination with E. coli. More than half of the respondents (59.2%) used water that had high risk of contamination and 61.3% of the latrines did not meet the criteria of a healthy latrine. Waste management practices of nearly all respondents (97.9%) were below the standards set by the Ministry of Health. More than half of the respondents (68.3%) did not wash their hands with soap for 20 seconds and 52.1% did not use flowing water for washing hands. Majority of the respondents' hands (57%, 81/142) and 72.2% (104/142) of the eating utensils were found to be contaminated by E. coli. Contaminated hands of food handlers were more likely to contaminate the babies food-serving utensils (OR: 3.7; 95%CI: 1.62-8.46, p 0.002). Contamination of the hands of food handler was associated with contamination of babies food-serving utensils by E. coli. Hence, food handlers should be trained on proper hand washing methods.

Implementation guide of internal contamination control

International Nuclear Information System (INIS)

Balter, Henia; Savio, Eduardo; Souto, Beatriz

1994-01-01

A review of current methods of contamination control for radioisotopes 131I, 125I and 99mTc, periodic control of personnel exposed to radiation.Maximum permissible body burden (Mpbb) for each radionuclide,radiotoxicity as danger of internal contamination directly related with Let, type of radiation,Ali values for various radionuclides and external irradiation as an opposed factor.Effective half life,examples, 99mTc in urine,iodine in thyroid caption, 99m Tc absorption by skin and mouth. Procedure of control and calculation by measurement of urine samples in a gamma spectrometer. Iodine thyroid caption by monitoring of thyroid with a solid NaI(TI)scintillator taking as background radiation the activity of upper leg muscle. Standard solutions are prepared to fill a thyroid phantoms.Results must not be higher than Mpbb of corresponding radionuclide.Bibliography

Inventory assessment and determination of properties of dust contamination in the Shelter under-roof space

International Nuclear Information System (INIS)

Bogatov, S.A.

2000-01-01

Experimental results on study of radionuclide contamination of surfaces under the roof of Shelter have been analyzed. Values of 'loose' and fixed fuel contamination densities and aerodynamic diameters of dust particles capable of resuspension are obtained. Long term efficiency of dust suppression system under the Shelter roof has been estimated. On the base of retrospective analysis of the results, fuel dust inventory on the surfaces under the Shelter roof was evaluated. 14 refs., 5 tab., 3 figs

Algal tests with soil suspensions and elutriates: A comparative evaluation for PAH contaminated soils

DEFF Research Database (Denmark)

Baun, Anders; Justesen, Kasper Bo; Nyholm, Niels

2002-01-01

An algal growth inhibition test procedure with soil suspensions is proposed and evaluated for PAH-contaminated soil. The growth rate reduction of the standard freshwater green alga Pseudokirchneriella subcapitata (formerly known as Selenastrum capricornutum) was used as the toxicity endpoint......, and was quantified by measuring the fluorescence of solvent-extracted algal pigments. No growth rate reduction was detected for soil contents up to 20 g/l testing five non-contaminated Danish soils. Comparative testing with PAH-contaminated soil elutriates and soil suspensions showed that the suspensions had...

Passive sampling methods for contaminated sediments: State of the science for organic contaminants

Science.gov (United States)

Lydy, Michael J; Landrum, Peter F; Oen, Amy MP; Allinson, Mayumi; Smedes, Foppe; Harwood, Amanda D; Li, Huizhen; Maruya, Keith A; Liu, Jingfu

2014-01-01

This manuscript surveys the literature on passive sampler methods (PSMs) used in contaminated sediments to assess the chemical activity of organic contaminants. The chemical activity in turn dictates the reactivity and bioavailability of contaminants in sediment. Approaches to measure specific binding of compounds to sediment components, for example, amorphous carbon or specific types of reduced carbon, and the associated partition coefficients are difficult to determine, particularly for native sediment. Thus, the development of PSMs that represent the chemical activity of complex compound–sediment interactions, expressed as the freely dissolved contaminant concentration in porewater (Cfree), offer a better proxy for endpoints of concern, such as reactivity, bioaccumulation, and toxicity. Passive sampling methods have estimated Cfree using both kinetic and equilibrium operating modes and used various polymers as the sorbing phase, for example, polydimethylsiloxane, polyethylene, and polyoxymethylene in various configurations, such as sheets, coated fibers, or vials containing thin films. These PSMs have been applied in laboratory exposures and field deployments covering a variety of spatial and temporal scales. A wide range of calibration conditions exist in the literature to estimate Cfree, but consensus values have not been established. The most critical criteria are the partition coefficient between water and the polymer phase and the equilibrium status of the sampler. In addition, the PSM must not appreciably deplete Cfree in the porewater. Some of the future challenges include establishing a standard approach for PSM measurements, correcting for nonequilibrium conditions, establishing guidance for selection and implementation of PSMs, and translating and applying data collected by PSMs. Integr Environ Assess Manag 2014;10:167–178. © 2014 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of

New reclamation standards for oil and gas well sites and pipelines in the agricultural land reserve

International Nuclear Information System (INIS)

Jones, P.

1995-01-01

Reclamation standards are a necessity because of increasing density of oil and gas developments, and the number of wells which may be abandoned over the next few years. All petroleum industry users of land are subject to the Agricultural Land Commission Act and require the approval of the Commission. The new General Order 293/95 was discussed, the purpose of which is to streamline existing regulations and to clarify reclamation standards. The new standards are similar to requirements currently in place in northwestern Alberta because landforms, soils, and land there are similar to those that exist in the Peace River region of B.C. Adopting similar requirements also has the added benefit of providing consistency for the industry between adjacent jurisdictions. In essence, the official view is that petroleum developments are temporary activities as long as the land is restored to its original or better condition, and the disruption to farm operations is minimal. Major provisions of General Order 293/95 were reviewed. It was noted that site contamination and the disposal of wastes were not addressed in the General Order. The reason for this is that these matters fall under the jurisdiction of other government agencies. 7 refs

Anatomic-physiological schema of the gastrointestinal tract, to be taken in account in determining the levels of radioactive contamination; Schema anatomo-physiologique du tractus gastro-intestinal a prendre en consideration pour le calcul des niveaux de contamination Radioactive

Energy Technology Data Exchange (ETDEWEB)

Fabry, C [Commissariat a l' Energie Atomique, Cadarache, Association EURATOM-CEA, Niveaux de Contamination (France). Centre d' Etudes Nucleaires

1964-07-01

Anatomical and physiological data of the gastrointestinal tract of adults and children were summarized in a standard schema, to be used in calculating the levels of radioactive contamination, in the food chain. (author) [French] Cette note a pour objet de rassembler les donnees anatomiques et physiologiques du tractus gastrointestinal, chez l'adulte et chez l'enfant, et d'en deduire un schema standard qui puisse servir de base au calcul des niveaux de contamination de la chaine alimentaire par les substances radioactives. (auteur)

Suction/inspiration against resistance or standardized Mueller maneuver: a new breathing technique to improve contrast density within the pulmonary artery: a pilot CT study

Energy Technology Data Exchange (ETDEWEB)

Gutzeit, Andreas [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Hirslanden Hospital St. Anna, Institute of Radiology and Nuclear Medicine, Clinical Research Unit, Lucerne (Switzerland); Kantonsspital Winterthur, Department of Radiology, Winterthur (Switzerland); Froehlich, Johannes M.; Weymarn, Constantin von; Goyen, Matthias [Hirslanden Hospital St. Anna, Institute of Radiology and Nuclear Medicine, Clinical Research Unit, Lucerne (Switzerland); Waelti, Stephan [Cantonal Hospital St. Gallen, Department of Radiology and Nuclear Medicine, St. Gallen (Switzerland); Roos, Justus E. [Duke University Medical Center, Department of Radiology, Durham, NC (United States); Meissnitzer, Matthias; Hergan, Klaus [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Czell, David [Cantonal Hospital Winterthur, Department of Neurology, Winterthur (Switzerland); Reischauer, Carolin [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Hirslanden Hospital St. Anna, Institute of Radiology and Nuclear Medicine, Clinical Research Unit, Lucerne (Switzerland)

2015-11-15

Our aim was to prospectively investigate whether the recently introduced suction/inspiration against resistance breathing method leads to higher computed tomography (CT) contrast density in the pulmonary artery compared to standard breathing. The present study was approved by the Medical Ethics committee and all subjects gave written informed consent. Fifteen patients, each without suspicious lung emboli, were randomly assigned to four different groups with different breathing maneuvers (suction against resistance, Valsalva, inspiration, expiration) during routine CT. Contrast enhancement in the central and peripheral sections of the pulmonary artery were measured and compared with one another. Peripheral enhancement during suction yielded increased mean densities of 138.14 Hounsfield units (HU) (p = 0.001), compared to Valsalva and a mean density of 67.97 HU superior to inspiration (p = 0.075). Finally, suction in comparison to expiration resulted in a mean increase of 30.51 HU (p = 0.42). Central parts of pulmonary arteries presented significantly increased enhancement values (95.74 HU) for suction versus the Valsalva technique (p = 0.020), while all other mean densities were in favour of suction (versus inspiration: p = 0.201; versus expiration: p = 0.790) without reaching significance. Suction/Inspiration against resistance is a promising technique to improve contrast density within pulmonary vessels, especially in the peripheral parts, in comparison to other breathing maneuvers. (orig.)

Ionization Potentials of Chemical Warfare Agents and Related Compounds Determined with Density Functional Theory

National Research Council Canada - National Science Library

Wright, J

2000-01-01

...) agents at contaminated sites. Reported herein are theoretical ionization potentials for CW agents and their related compounds calculated using density functional theory at the B3LYP/6-311+G(2d,p) level of theory...

The recuperation of sulphuric acid out of contaminated solutions by electro electrodialysis; De recuperatie van zwavelzuur uit gecontamineerde oplossingen door elektro elektrodialyse

Energy Technology Data Exchange (ETDEWEB)

Cattoir, S

1997-05-01

The dismantling of a nuclear reactor results in large amounts of contaminated waste. The amount of waste is minimized by so-called decontamination processes. These decontamination processes result in decontaminated metal as well as contaminated effluents, containing acid and metal salts. Standard treatment of these effluents involves neutralisation of the acid using sodium hydroxide, resulting in the precipitation of hydroxides; and evaporation of the solvent. However, if the acid is extracted out of the decontamination effluents prior to neutralisation, this acid can be re-used in the decontamination process, substantially reducing the final waste. This report investigates the possibility of using Electro Electrodialysis (EED) for the extraction of 900 moles of sulphuric acid out of a 1 m{sup 3} contaminated solution, containing 22 kg of ferrous, chromous, cerous and nickel ions and 1000 moles of sulphuric acid. EED removes acids out of acid/salts solutions, using an electrolyser equipped with an anionic membrane: the acid-anion is displaced by migration through the membrane while the proton is displaced by electrolysis. This report gives a full description of the technique, the lab-scale apparatus, the analyses involved in studying the technique on lab-scale or monitoring it on full scale, the choice of electrode and membrane and of process parameters such as temperature and current density. On lab scale, EED can displace 90% of the acid out of the acid/salt solution just described, at a current density as high as 0.14 A.cm{sup -2}, at 50 degrees Celsius, if the cathode and the anode are of smoothed platina or of platinised titanium, and the anion selective membrane is the Neosepta AMH -membrane of Tokuyama. The study of EED still needs to be completed with a further study of metal deposition on the cathode, and a comparison of the technique to other (electro)membrane techniques.

Assessment of the bacterial contamination of hand air dryer in washrooms

OpenAIRE

Alharbi, Sulaiman Ali; Salmen, Saleh Hussein; Chinnathambi, Arunachalam; Alharbi, Naiyf S.; Zayed, M.E.; Al-Johny, Bassam O.; Wainwright, Milton

2016-01-01

The present study was carried out, using standard techniques, to identify and count the bacterial contamination of hand air dryers, used in washrooms. Bacteria were isolated from the air flow, outlet nozzle of warm air dryers in fifteen air dryers used in these washrooms. Bacteria were found to be relatively numerous in the air flows. Bacterially contaminated air was found to be emitted whenever a warm air dryer was running, even when not being used for hand drying. Our investigation shows th...

Rapid radiometric detection of microbial contamination using 14C-glucose and standard liquid scintillation counting system

International Nuclear Information System (INIS)

Joshi, S.H.; Kamble, S.B.; Pilkhwal, N.S.; Ramamoorthy, N.

1998-01-01

A simple and rapid method for detection of microbial contamination based on quantitation of 14 CO 2 released during metabolism of 14 C-Glucose by microorganisms is reported. Liquid scintillation counting system (LSCS) with a modified sample preparation method was utilised. The scintillator was impregnated on Whatman-1 paper on which 14 CO 2 evolved during metabolism could be absorbed. The important parameters of counting such as efficiency, position sensitivity and geometry as well as effect of NaOH quantity and of microbial load on detection period were studied. The efficiency of radioactivity assay was 18±2.8 %. Contamination of the order of 5-10 organism/ml of product could be detected in about 24 hours. (author)

Radiation contamination monitors

International Nuclear Information System (INIS)

Kato, Tsutomu; Iba, Hiroshi; Sato, Hiroshi

1999-01-01

To make sure of no contamination on people, used articles and working uniforms coming out of the radiation controlled area, nuclear power plants are equipped with radioactive contamination monitors. This paper outlines the basic specifications and advantages of our personnel surface contamination monitors to inspect whole-body surface contamination of people coming out, article surface contamination monitors to inspect the surface and inside contamination of used articles brought out, laundry monitors to inspect surface contamination of working uniforms used in the area before and after a wash, and whole-body counters to inspect and measure the internal contamination of a person out of the area. (author)

How to establish practical rules for the avoidance of contamination; Comment etablir des regles pratiques pour eviter la contamination

Energy Technology Data Exchange (ETDEWEB)

Duhamel, F.; Lavie, J.M. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1960-07-01

The international Commission for Radiation Protection has given, for the most common radioelements, the internal contamination standards corresponding to a permanent exposure to these risks. These standards, expressed in maximum permissible concentrations in air, cannot be used directly for defining regulations aiming at avoiding the respiration of large doses during a short time. That is why the authors of this report have established a basis of comparison for the radioelements using the idea of the maximum permissible intake quantity 'Q.M.I.' for a single dose. (author) [French] La Commission internationale de Protection contre les Radiations 'I.C.R.P.' a donne, pour les radioelements les plus courants, les normes de contamination interne correspondant a une exposition permanente a ces risques. Ces normes, exprimees en concentrations maximales admissibles dans l'air ne sont pas directement utilisables pour elaborer directement un reglement cherchant a eviter les inhalations importantes mais de courte duree. C'est pourquoi, les auteurs de ce rapport ont etabli une base de comparaison des radioelements en faisant appel a la notion de quantite maximale inhalable 'Q.M.I.' en une seule fois. (auteur)

How to establish practical rules for the avoidance of contamination; Comment etablir des regles pratiques pour eviter la contamination

Energy Technology Data Exchange (ETDEWEB)

Duhamel, F; Lavie, J M [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1960-07-01

The international Commission for Radiation Protection has given, for the most common radioelements, the internal contamination standards corresponding to a permanent exposure to these risks. These standards, expressed in maximum permissible concentrations in air, cannot be used directly for defining regulations aiming at avoiding the respiration of large doses during a short time. That is why the authors of this report have established a basis of comparison for the radioelements using the idea of the maximum permissible intake quantity 'Q.M.I.' for a single dose. (author) [French] La Commission internationale de Protection contre les Radiations 'I.C.R.P.' a donne, pour les radioelements les plus courants, les normes de contamination interne correspondant a une exposition permanente a ces risques. Ces normes, exprimees en concentrations maximales admissibles dans l'air ne sont pas directement utilisables pour elaborer directement un reglement cherchant a eviter les inhalations importantes mais de courte duree. C'est pourquoi, les auteurs de ce rapport ont etabli une base de comparaison des radioelements en faisant appel a la notion de quantite maximale inhalable 'Q.M.I.' en une seule fois. (auteur)

Impact of Some Ecological Factors on Fecal Contamination of Drinking Water by Diarrheagenic Antibiotic-Resistant Escherichia coli in Zagazig City, Egypt

Directory of Open Access Journals (Sweden)

Ahmed Elsadek Fakhr

2016-01-01

Full Text Available Fecal contamination of drinking water is a major health problem which accounts for many cases of diarrhea mainly in infants and foreigners. This contamination is a complex interaction of many parameters. Antibiotic resistance among bacterial isolates complicates the problem. The study was done to identify fecal contamination of drinking water by Diarrheagenic Antibiotic-Resistant Escherichia coli in Zagazig city and to trace reasons for such contamination, three hundred potable water samples were investigated for E. coli existence. Locations of E. coli positive samples were investigated in relation to population density, water source, and type of water pipe. Sixteen E. coli strains were isolated. Antibiotic sensitivity was done and enterotoxigenic, enteropathogenic, and enterohaemorrhagic virulence genes were investigated by PCR. Probability of fecal contamination correlated with higher population density, with increased distance from Zagazig water plant, and with asbestos cement water pipes. Resistance to at least one antimicrobial drug was found in all isolates. Virulence genes were detected in a rate of 26.27%, 13.13%, 20%, 6.67%, and 33.33% for LT, ST, stx1, stx2, and eae genes, respectively. This relatively high frequency of fecal contamination points towards the high risk of developing diarrhea by antibiotic resistant DEC in low socioeconomic communities particularly with old fashion distribution systems.

Role of subtyping in detecting Salmonella cross contamination in the laboratory.

LENUS (Irish Health Repository)

De Lappe, Niall

2009-01-01

BACKGROUND: With the exception of M. tuberculosis, little has been published on the problems of cross-contamination in bacteriology laboratories. We performed a retrospective analysis of subtyping data from the National Salmonella Reference Laboratory (Ireland) from 2000-2007 to identify likely incidents of laboratory cross contamination. METHODS: Serotyping and antimicrobial susceptibility testing was performed on all Salmonella isolates received in the NSRL. Phage typing was performed on all S. Typhimurium and S. Enteritidis isolates while multi-locus variance analysis (MLVA) was performed on selected S. Typhimurium isolates. Pulsed field gel electrophoresis (PFGE) using the PulseNet standard protocol was performed on selected isolates of various serovars. RESULTS: Twenty-three incidents involving fifty-six isolates were identified as likely to represent cross contamination. The probable sources of contamination identified were the laboratory positive control isolate (n = 13), other test isolates (n = 9) or proficiency test samples (n = 1). CONCLUSION: The scale of laboratory cross-contamination in bacteriology is most likely under recognized. Testing laboratories should be aware of the potential for cross-contamination, regularly review protocols to minimize its occurrence and consider it as a possibility when unexpected results are obtained.

Precision density measuring equipment: Design, selected examples

International Nuclear Information System (INIS)

Karasinski, T.; Patzelt, K.; Dieker, C.; Hansen, H.; Wenzl, H.; Schober, T.

1987-06-01

The report deals with solids density measurement using the pyknometer, the hydrostatic balance, or the floating specimen method. The mathematical relations are derived, and error sources are shown. A detailed description is given of a measuring set-up for measuring the density of solids and liquids. An error calculation is presented. After explaining the determination of density of a standard solid body, the report describes the density measurement of monocrystalline germanium, of niobium-tritide, Ni 3 Al, Ge-Si, and gallium arsenide, the determination of space-lattice expansion by hydrogen isotopes, and of the purity of H-D mixtures. (GG) [de

The Feasibility of Tree Coring as a Screening Tool for Selected Contaminants in the Subsurface

DEFF Research Database (Denmark)

Nielsen, Mette Algreen

Chemical release resulting from inadequate care in the handling and storage of compounds has ultimately led to a large number of contaminated sites worldwide. Frequently found contaminants in the terrestrial environment include BTEX (benzene, toluene, ethylbenzene, and xylenes), heavy metals, PAH...... sampling density. This, together with a relatively large soil volume represented by a tree core, has shown to reduce the risk of overlooking contaminated areas and is a valuable method for the identification of previously unknown source areas within a short time period....... (polycyclic aromatic hydrocarbons) and chlorinated solvents. The large number of contaminated sites has created a need for effective and reliable site investigations. In this PhD project the feasibility of tree coring as a screening tool for selected contaminants in the subsurface has been investigated...... to obtain more efficient site investigations. Trees have a natural ability to take up water and nutrients from the subsurface; consequently, contaminants can also enter the roots and be translocated to plant parts above ground where they will be absorbed, degraded or phytovolatilized depending...

Control of the surface radioactive contamination in the field of biological research

International Nuclear Information System (INIS)

Calvo, S.; Encina, A. de la; Gaspar, J.; Macias, M. T.; Sanchez, A.; Usera, F.

2012-01-01

The manipulation of unsealed sources in biomedical research involves significant risk of radioactive contamination. the aim of this study has been to analyze the radioactive contamination occurring in the field of biomedical research, assessing its magnitude, identifying the equipment that can be contaminated with higher probability and monitoring the evolution of the contaminations production taking into account the radioisotopes and the activities uses, and the radiation protection control applied. The data used for this study correspond to a very lengthy period of time and it have been collected in the radioactive facility, of the Centro Nacional de Biotecnologia (CSIC), a very large biological research centre that can be used perfectly as a reference for this area. The results obtained show a gradual and significant decrease in the incidence of the radioactive contamination. This is due to the optimization of radiation protection standards applied and the implementation or a systematic operational radiation protection program. (Author) 13 refs.

Parasitic Contamination in Commonly- Consumed Vegetables in Mazandaran Province, Northern Iran

Directory of Open Access Journals (Sweden)

Mehdi Sharif

2017-03-01

Full Text Available Background: Raw (fresh vegetables are an important ingredient of healthy diet. Many enteric bacterial, parasitic and viral pathogens could be transmitted by vegetables. Mazandaran province is located in northern Iran with a coastal area and extensive fields for vegetable cultivation. The current study is designed to evaluate the parasitic contamination of fresh vegetables. Methods: A total of 150 samples of fresh vegetables obtained from markets were examined for parasitic infections using standard methods. Results: Out of 104 samples (60.3% were contaminated with parasites. Parsley and radish with prevalence rates of 90% (18/20 and 39.1% (9/23 were the most and least contaminated vegetables. Free living larva and Trichostrongylus were the most and least common parasites in our results. Conclusion: It can be concluded that parasitological contamination of raw vegetables may be a health threat to consumers of such products.

Level density from realistic nuclear potentials

International Nuclear Information System (INIS)

Calboreanu, A.

2006-01-01

Nuclear level density of some nuclei is calculated using a realistic set of single particle states (sps). These states are derived from the parameterization of nuclear potentials that describe the observed sps over a large number of nuclei. This approach has the advantage that one can infer level density for nuclei that are inaccessible for a direct study, but are very important in astrophysical processes such as those close to the drip lines. Level densities at high excitation energies are very sensitive to the actual set of sps. The fact that the sps spectrum is finite has extraordinary consequences upon nuclear reaction yields due to the leveling-off of the level density at extremely high excitation energies wrongly attributed so far to other nuclear effects. Single-particle level density parameter a parameter is extracted by fitting the calculated densities to the standard Bethe formula

Breast density quantification with cone-beam CT: a post-mortem study

International Nuclear Information System (INIS)

Johnson, Travis; Ding, Huanjun; Le, Huy Q; Ducote, Justin L; Molloi, Sabee

2013-01-01

Forty post-mortem breasts were imaged with a flat-panel based cone-beam x-ray CT system at 50 kVp. The feasibility of breast density quantification has been investigated using standard histogram thresholding and an automatic segmentation method based on the fuzzy c-means algorithm (FCM). The breasts were chemically decomposed into water, lipid, and protein immediately after image acquisition was completed. The per cent fibroglandular volume (%FGV) from chemical analysis was used as the gold standard for breast density comparison. Both image-based segmentation techniques showed good precision in breast density quantification with high linear coefficients between the right and left breast of each pair. When comparing with the gold standard using %FGV from chemical analysis, Pearson's r-values were estimated to be 0.983 and 0.968 for the FCM clustering and the histogram thresholding techniques, respectively. The standard error of the estimate was also reduced from 3.92% to 2.45% by applying the automatic clustering technique. The results of the postmortem study suggested that breast tissue can be characterized in terms of water, lipid and protein contents with high accuracy by using chemical analysis, which offers a gold standard for breast density studies comparing different techniques. In the investigated image segmentation techniques, the FCM algorithm had high precision and accuracy in breast density quantification. In comparison to conventional histogram thresholding, it was more efficient and reduced inter-observer variation. (paper)

Anatomic-physiological schema of the gastrointestinal tract, to be taken in account in determining the levels of radioactive contamination; Schema anatomo-physiologique du tractus gastro-intestinal a prendre en consideration pour le calcul des niveaux de contamination Radioactive

Energy Technology Data Exchange (ETDEWEB)

Fabry, C. [Commissariat a l' Energie Atomique, Cadarache, Association EURATOM-CEA, Niveaux de Contamination (France). Centre d' Etudes Nucleaires

1964-07-01

Anatomical and physiological data of the gastrointestinal tract of adults and children were summarized in a standard schema, to be used in calculating the levels of radioactive contamination, in the food chain. (author) [French] Cette note a pour objet de rassembler les donnees anatomiques et physiologiques du tractus gastrointestinal, chez l'adulte et chez l'enfant, et d'en deduire un schema standard qui puisse servir de base au calcul des niveaux de contamination de la chaine alimentaire par les substances radioactives. (auteur)

40 CFR 141.61 - Maximum contaminant levels for organic contaminants.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Maximum contaminant levels for organic contaminants. 141.61 Section 141.61 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER... Regulations: Maximum Contaminant Levels and Maximum Residual Disinfectant Levels § 141.61 Maximum contaminant...

Experience of rehabilitation of territories contaminated during Chernobyl NPP accident in Ukraine

International Nuclear Information System (INIS)

Zeleznyak, M.

2003-01-01

Polessie. Dose loads for human were determined by intensity of cesium radionuclides entry in an organism through agricultural food chains. Cesium content in a ration is determined not only by the density of fallout, but also by ecological conditions, as type of soil, its water regime, and technologies of plant and animal products industries. Both the effective irradiation dose for inhabitants of contaminated areas consumed local foodstuffs, and the density of territory contamination were used as basic criterion of radiation danger. It has not allowed to concentrate material resources an the most critical objects. The specific feature of 'Chernobyl' radioactive fallout is the considerable heterogeneity of spatial distribution. The detail monitoring of soils and compiling of cartograms of contamination of all agricultural lands in a zone of emergency has been demanded. The most critical objects was appeared to be peat soils, pastures and hay-makings an flood lands; hay obtained on them was characterized by the high content 137 Cs even at a low density of radioactive contamination of soil -10-30 kBq*m -2 . Program of agricultural countermeasures implementation with aim of reduction of radioactive contamination of foodstuffs was elaborated and realized In Ukraine. The main share of population irradiation dose is formed in the initial 5-7 years after emergency. Natural processes (auto-rehabilitation) decreasing geochemical mobility of 137 Cs in a soil and its biological availability to plants play significant role in improvement of radiation situation in this period. The processes of an auto-rehabilitation led to decrease of 137 Cs transfer factors values to plants from 3 up to 30 times. Countermeasures application was most effective an pastures where TF decreased 2 - 14 times. The application of the fodder additives (ferrocines and natural sorbents - zeolites) permitted to decrease a level of cow milk contamination up to 2 - 10 times. Cow meat consumption causes about -20 % of

Reducing Organic Contamination in NASA JSC Astromaterial Curation Facility

Science.gov (United States)

Calaway, M. J.; Allen, C. C.; Allton, J. H.

2013-01-01

Future robotic and human spaceflight missions to the Moon, Mars, asteroids and comets will require handling and storing astromaterial samples with minimal inorganic and organic contamination to preserve the scientific integrity of each sample. Much was learned from the rigorous attempts to minimize and monitor organic contamination during Apollo, but it was not adequate for current analytical requirements; thus [1]. OSIRIS-REx, Hayabusa-2, and future Mars sample return will require better protocols for reducing organic contamination. Future isolation con-tainment systems for astromaterials, possibly nitrogen enriched gloveboxes, must be able to reduce organic and inorganic cross-contamination. In 2012, a baseline study established the current state of organic cleanliness in gloveboxes used by NASA JSC astromaterials curation labs that could be used as a benchmark for future mission designs [2, 3]. After standard ultra-pure water (UPW) cleaning, the majority of organic contaminates found were hydrocarbons, plasticizers, silicones, and solvents. Hydro-carbons loads (> C7) ranged from 1.9 to 11.8 ng/cm2 for TD-GC-MS wafer exposure analyses and 5.0 to 19.5 ng/L for TD-GC-MS adsorbent tube exposure. Plasticizers included peracetic acid sterilization were used in the atmospheric de-contamination (R) cabinets. Later, Lunar curation gloveboxes were degreased with a pressurized Freon 113 wash. Today, UPW has replaced Freon as the standard cleaning procedure, but does not have the degreasing solvency power of Freon. Future Cleaning Studies: Cleaning experiments are cur-rently being orchestrated to study how to degrease and reduce organics in a JSC curation glovebox lower than the established baseline. Several new chemicals in the industry have replaced traditional degreasing solvents such as Freon and others that are now federally restricted. However, these new suites of chemicals remain untested for lowering organics in curation gloveboxes. 3M's HFE-7100DL and Du

Development of bagless transfer system for standard waste boxes

International Nuclear Information System (INIS)

Presgrove, S.B.; Patel, K.

1991-01-01

At several DOE site, substantial volumes of Transuranic (TRU) waste has been handled on a daily basis. Usually, the waste has been transferred from the facilities to the Waste Isolation Pilot Plant (WIPP) or to an on site storage facility using the ''bag-out'' technique. This process begins in the most contaminated area by placing the waste in a strong plastic bag, twisting closed the neck of the bag, then taping the closed neck. This reduces the exposed TRU waste and the resulting contamination. However, even though that the contamination is reduced, it remains high enough to prevent direct transfer into the environment. In order to reduce the contamination to acceptable levels, the ''bag-out'' process is repeated until the outside contamination on the plastic bag is acceptable. This procedure has been affective, however, it also generates organic waste in the process. During the design of the Transuranic Waste Facility (TWF) at the Savannah River Site, a conceptual alternative was developed using the Standard Waste Box (SWB)

The long-term problems of contaminated land: Sources, impacts and countermeasures

International Nuclear Information System (INIS)

Baes, C.F. III.

1986-11-01

This report examines the various sources of radiological land contamination; its extent; its impacts on man, agriculture, and the environment; countermeasures for mitigating exposures; radiological standards; alternatives for achieving land decontamination and cleanup; and possible alternatives for utilizing the land. The major potential sources of extensive long-term land contamination with radionuclides, in order of decreasing extent, are nuclear war, detonation of a single nuclear weapon (e.g., a terrorist act), serious reactor accidents, and nonfission nuclear weapons accidents that disperse the nuclear fuels (termed ''broken arrows'')

Bacterial Contamination of Iranian Paper Currency and Their Antibiotic Resistance Patterns

Directory of Open Access Journals (Sweden)

Farzaneh Firoozeh

2017-11-01

Full Text Available Background: Paper currency is used in exchange for services, and thisis why the circulation of paper currency from person to person expandsmicroorganisms. Objectives:: Paper banknotes would be a vector for transmission of pathogenic microorganisms through handling. This study aimed to determine bacterial contamination of Iranian paper currencies in circulation and their antibiotic resistance patterns. Materials and Methods: In this study, 337 currency notes of different value were collected from markets, shops, restaurants, bus stations and banks in Kashan, Iran during April 2015 to March 2016. The currency notes transferred to microbiology laboratory and were tested for bacterial contamination using standard microbiological methods. Antibiotic resistance patterns of isolated bacteria were determined by disk diffusion method according to CLSI standards. The results and data were analyzed using descriptive statistics. Results: Of 337 currency notes, 262 (77.7% were identified with bacterial contamination. Bacteria isolated from currency notes were as follows: Bacillus spp 113 (43.1%, coagulase-negative Staphylococci 99 (37.7%, Escherichia coli 20 (7.6%, Enterococci species 14 (5.3%, Staphylococcus aureus 8 (3.1%, Klebsiella spp 4 (1.5%, Shigella species 2 (0.8%, Pseudomonas species 2 (0.8%. The most and least contaminated currency notes were 50000 and 500 Rials, respectively. The most resistance rates in gram negative rods were against nalidixicacid, and ampicillin. Also most resistance rates in Staphylococcus aureus, coagulase-negative Staphylococci and Enterococci species were against ampicillin, erythromycin and tetracycline. Conclusion: Our study revealed that the bacterial contamination among Iranian paper currency in circulation especially those obtained from certain sources including shops and bus stations is high and in most cases these bacterial isolates are antibiotic resistant strains.

Evaluation of macromolecular electron-density map quality using the correlation of local r.m.s. density

International Nuclear Information System (INIS)

Terwilliger, Thomas C.; Berendzen, Joel

1999-01-01

The correlation of local r.m.s. density is shown to be a good measure of the presence of distinct solvent and macromolecule regions in macromolecular electron-density maps. It has recently been shown that the standard deviation of local r.m.s. electron density is a good indicator of the presence of distinct regions of solvent and protein in macromolecular electron-density maps [Terwilliger & Berendzen (1999 ▶). Acta Cryst. D55, 501–505]. Here, it is demonstrated that a complementary measure, the correlation of local r.m.s. density in adjacent regions on the unit cell, is also a good measure of the presence of distinct solvent and protein regions. The correlation of local r.m.s. density is essentially a measure of how contiguous the solvent (and protein) regions are in the electron-density map. This statistic can be calculated in real space or in reciprocal space and has potential uses in evaluation of heavy-atom solutions in the MIR and MAD methods as well as for evaluation of trial phase sets in ab initio phasing procedures

Regulatory approaches to hydrocarbon contamination from underground storage tanks

International Nuclear Information System (INIS)

Daugherty, S.J.

1991-01-01

Action or lack of action by the appropriate regulatory agency is often the most important factor in determining remedial action or closure requirements for hydrocarbon contaminated sites. This paper reports that the diversity of regulatory criteria is well known statewide and well documented nationally. In California, the diversity of approaches is due to: that very lack of a clear understanding of the true impact of hydrocarbon contamination: lack of state or federal standards for soil cleanup, and state water quality objectives that are not always achievable; vagueness in the underground storage tank law; and the number and diversity of agencies enforcing the underground storage tank regulations

Standard Test Method for Contamination Outgassing Characteristics of Spacecraft Materials

CERN Document Server

American Society for Testing and Materials. Philadelphia

2009-01-01

1.1 This test method covers a technique for generating data to characterize the kinetics of the release of outgassing products from materials. This technique will determine both the total mass flux evolved by a material when exposed to a vacuum environment and the deposition of this flux on surfaces held at various specified temperatures. 1.2 This test method describes the test apparatus and related operating procedures for evaluating the total mass flux that is evolved from a material being subjected to temperatures that are between 298 and 398 K. Pressures external to the sample effusion cell are less than 7 × 10−3 Pa (5 × 10−5 torr). Deposition rates are measured during material outgassing tests. A test procedure for collecting data and a test method for processing and presenting the collected data are included. 1.3 This test method can be used to produce the data necessary to support mathematical models used for the prediction of molecular contaminant generation, migration, and deposition. 1.4 Al...

Standard Guide for Post-Deactivation Surveillance and Maintenance of Radiologically Contaminated Facilities

CERN Document Server

American Society for Testing and Materials. Philadelphia

2010-01-01

1.1 This guide outlines a method for developing a Surveillance and Maintenance (S&M) plan for inactive nuclear facilities. It describes the steps and activities necessary to prevent loss or release of radioactive or hazardous materials, and to minimize physical risks between the deactivation phase and the start of facility decontamination and decommissioning (D&D). 1.2 The primary concerns for S&M are related to (1) animal intrusion, (2) structural integrity degradation, (3) water in-leakage, (4) contamination migration, (5) unauthorized personnel entry, and (6) theft/intrusion. This document is intended to serve as a guide only, and is not intended to modify existing regulations.

Absolute Salinity, ''Density Salinity'' and the Reference-Composition Salinity Scale: present and future use in the seawater standard TEOS-10

Science.gov (United States)

Wright, D. G.; Pawlowicz, R.; McDougall, T. J.; Feistel, R.; Marion, G. M.

2011-01-01

Salinity plays a key role in the determination of the thermodynamic properties of seawater and the new TEOS-101 standard provides a consistent and effective approach to dealing with relationships between salinity and these thermodynamic properties. However, there are a number of practical issues that arise in the application of TEOS-10, both in terms of accuracy and scope, including its use in the reduction of field data and in numerical models. First, in the TEOS-10 formulation for IAPSO Standard Seawater, the Gibbs function takes the Reference Salinity as its salinity argument, denoted SR, which provides a measure of the mass fraction of dissolved material in solution based on the Reference Composition approximation for Standard Seawater. We discuss uncertainties in both the Reference Composition and the Reference-Composition Salinity Scale on which Reference Salinity is reported. The Reference Composition provides a much-needed fixed benchmark but modified reference states will inevitably be required to improve the representation of Standard Seawater for some studies. However, the Reference-Composition Salinity Scale should remain unaltered to provide a stable representation of salinity for use with the TEOS-10 Gibbs function and in climate change detection studies. Second, when composition anomalies are present in seawater, no single salinity variable can fully represent the influence of dissolved material on the thermodynamic properties of seawater. We consider three distinct representations of salinity that have been used in previous studies and discuss the connections and distinctions between them. One of these variables provides the most accurate representation of density possible as well as improvements over Reference Salinity for the determination of other thermodynamic properties. It is referred to as "Density Salinity" and is represented by the symbol SAdens; it stands out as the most appropriate representation of salinity for use in dynamical physical

Absolute Salinity, "Density Salinity" and the Reference-Composition Salinity Scale: present and future use in the seawater standard TEOS-10

Science.gov (United States)

Wright, D. G.; Pawlowicz, R.; McDougall, T. J.; Feistel, R.; Marion, G. M.

2010-08-01

Salinity plays a key role in the determination of the thermodynamic properties of seawater and the new TEOS-101 standard provides a consistent and effective approach to dealing with relationships between salinity and these thermodynamic properties. However, there are a number of practical issues that arise in the application of TEOS-10, both in terms of accuracy and scope, including its use in the reduction of field data and in numerical models. First, in the TEOS-10 formulation for IAPSO Standard Seawater, the Gibbs function takes the Reference Salinity as its salinity argument, denoted SR, which provides a measure of the mass fraction of dissolved material in solution based on the Reference Composition approximation for Standard Seawater. We discuss uncertainties in both the Reference Composition and the Reference-Composition Salinity Scale on which Reference Salinity is reported. The Reference Composition provides a much-needed fixed benchmark but modified reference states will inevitably be required to improve the representation of Standard Seawater for some studies. The Reference-Composition Salinity Scale should remain unaltered to provide a stable representation of salinity for use with the TEOS-10 Gibbs function and in climate change detection studies. Second, when composition anomalies are present in seawater, no single salinity variable can fully represent the influence of dissolved material on the thermodynamic properties of seawater. We consider three distinct representations of salinity that have been used in previous studies and discuss the connections and distinctions between them. One of these variables provides the most accurate representation of density possible as well as improvements over Reference Salinity for the determination of other thermodynamic properties. It is referred to as "Density Salinity" and is represented by the symbol SAdens; it stands out as the most appropriate representation of salinity for use in dynamical physical

Engineering the size and density of silicon agglomerates by controlling the initial surface carbonated contamination

Energy Technology Data Exchange (ETDEWEB)

Borowik, Ł., E-mail: Lukasz.Borowik@cea.fr [CEA, LETI, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Chevalier, N.; Mariolle, D.; Martinez, E.; Bertin, F.; Chabli, A.; Barbé, J.-C. [CEA, LETI, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)

2013-04-01

Actually, thermally induced thin-films dewetting silicon in the silicon-on-insulator is a way to obtain silicon agglomerates with a size and a density fixed by the silicon film thickness. In this paper we report a new method to monitor both the size and the density of the Si agglomerates thanks to the deposition of a carbon-like layer. We show that using a 5-nm thick layer of silicon and additional ≤1-nm carbonated layer; we obtain agglomerates sizes ranging from 35 nm to 60 nm with respectively an agglomerate density ranging from 38 μm{sup −2} to 18 μm{sup −2}. Additionally, for the case of strained silicon films an alternative dewetting mechanism can be induced by monitoring the chemical composition of the sample surface.

Legal standards concerning health and ecological implications of radioactively contaminated environments

International Nuclear Information System (INIS)

Dorian, T.F.

1991-01-01

The author decided to explore legal standards in this paper because they are to only norms but also representations or levels of requirements, excellence or attainment. They thus present a way to look at things, to measure them against others, and to set goals for them. In other words, legal standards, whether in legislation are a part of agency requirements, set goals for getting the job done and then can be used as measures about whether or not it is getting done right. When dealing with the multifaceted problems before us, it is important to put it into perspective. We need to look at it from many points of view but with a stable focus-just as one looks through a microscope or a telescope with different magnifications and fields of vision. To have a point of vie, however, both the experts and the general public need to have some way to judge issues. One way they can do so is to use legal standards

Bulk density calculations from prompt gamma ray yield

International Nuclear Information System (INIS)

Naqvi, A.A.; Nagadi, M.M.; Al-Amoudi, O.S.B.; Maslehuddin, M.

2006-01-01

Full text: The gamma ray yield from a Prompt Gamma ray Neutron Activation Analysis (PGNAA) setup is a linear function of element concentration and neutron flux in a the sample with constant bulk density. If the sample bulk density varies as well, then the element concentration and the neutron flux has a nonlinear correlation with the gamma ray yield [1]. The measurement of gamma ray yield non-linearity from samples and a standard can be used to estimate the bulk density of the samples. In this study the prompt gamma ray yield from Blast Furnace Slag, Fly Ash, Silica Fumes and Superpozz cements samples have been measured as a function of their calcium and silicon concentration using KFUPM accelerator-based PGNAA setup [2]. Due to different bulk densities of the blended cement samples, the measured gamma ray yields have nonlinear correlation with calcium and silicon concentration of the samples. The non-linearity in the yield was observed to increase with gamma rays energy and element concentration. The bulk densities of the cement samples were calculated from ratio of gamma ray yield from blended cement and that from a Portland cement standard. The calculated bulk densities have good agreement with the published data. The result of this study will be presented

Toxic fluoride and arsenic contaminated groundwater in the Lahore and Kasur districts, Punjab, Pakistan and possible contaminant sources

International Nuclear Information System (INIS)

Farooqi, Abida; Masuda, Harue; Firdous, Nousheen

2007-01-01

The present study is the first attempt to put forward possible sources of As, F - and SO 4 2- contaminated groundwater in the Kalalanwala area, Punjab, Pakistan. Five rainwater and 24 groundwater samples from three different depths were analyzed. Shallow groundwater from 24 to 27 m depth contained high F - (2.47-21.1 mg/L), while the groundwater samples from the deeper depth were free from fluoride contamination. All groundwater samples contained high As (32-1900 μg/L), in excess of WHO drinking water standards. The SO 4 2- ranges from 110 to 1550 mg/L. δ 34 S data indicate three sources for SO 4 2- air pollutants (5.5-5.7 per mille ), fertilizers (4.8 per mille ), and household waste (7.0 per mille ). Our important finding is the presence of SO 4 2- , As and F - in rainwater, indicating the contribution of these elements from air pollution. We propose that pollutants originate, in part, from coal combusted at brick factories and were mobilized promotionally by the alkaline nature of the local groundwater. - Simultaneous As and F - contamination of groundwater and possible pollutant sources are discussed

Microbial contamination of mobile phones in a health care setting in Alexandria, Egypt.

Science.gov (United States)

Selim, Heba Sayed; Abaza, Amani Farouk

2015-01-01

This study aimed at investigating the microbial contamination of mobile phones in a hospital setting. Swab samples were collected from 40 mobile phones of patients and health care workers at the Alexandria University Students' Hospital. They were tested for their bacterial contamination at the microbiology laboratory of the High Institute of Public Health. Quantification of bacteria was performed using both surface spread and pour plate methods. Isolated bacterial agents were identified using standard microbiological methods. Methicillin-resistant Staphylococcus aureus was identified by disk diffusion method described by Bauer and Kirby. Isolated Gram-negative bacilli were tested for being extended spectrum beta lactamase producers using the double disk diffusion method according to the Clinical and Laboratory Standards Institute recommendations. All of the tested mobile phones (100%) were contaminated with either single or mixed bacterial agents. The most prevalent bacterial contaminants were methicillin-resistant S. aureus and coagulase-negative staphylococci representing 53% and 50%, respectively. The mean bacterial count was 357 CFU/ml, while the median was 13 CFU/ml using the pour plate method. The corresponding figures were 2,192 and 1,720 organisms/phone using the surface spread method. Mobile phones usage in hospital settings poses a risk of transmission of a variety of bacterial agents including multidrug-resistant pathogens as methicillin-resistant S. aureus. The surface spread method is an easy and useful tool for detection and estimation of bacterial contamination of mobile phones.

Assessment of Microbial Contamination of Traditional Sweets in Yazd, Iran, in 2015

Directory of Open Access Journals (Sweden)

hamidreza nasehinia

2017-03-01

samples were tested in terms of such microorganisms as Enterobacteriaceae, Escherichia coli, yeasts, and molds, using the microbiological tests, which were based on the Iranian national standards.Results: According to the results, the prevalence rate of microbial contaminations was 33.8% (n=322. Furthermore, the “Pistachio Luz” and “Hajji Badam” had the highest (88.8% and lowest (0% prevalence rates of  microbial contamination, respectively. Additionally, the prevalence rate of contamination to Enterobacteriaceae, Escherichia coli, Molds, and Yeasts were 13.2%, 5%, 21.7%, and 11.4%, respectively. Conclusion: Given the high rate of microbial contamination in the traditional sweets, especially “Pistachio Luz”, offered in Yazd, more regulatory and monitoring measures should be taken in the production and distribution of these sweets. 

Dynamical Mass Measurements of Contaminated Galaxy Clusters Using Support Distribution Machines

Science.gov (United States)

Ntampaka, Michelle; Trac, Hy; Sutherland, Dougal; Fromenteau, Sebastien; Poczos, Barnabas; Schneider, Jeff

2018-01-01

We study dynamical mass measurements of galaxy clusters contaminated by interlopers and show that a modern machine learning (ML) algorithm can predict masses by better than a factor of two compared to a standard scaling relation approach. We create two mock catalogs from Multidark’s publicly available N-body MDPL1 simulation, one with perfect galaxy cluster membership infor- mation and the other where a simple cylindrical cut around the cluster center allows interlopers to contaminate the clusters. In the standard approach, we use a power-law scaling relation to infer cluster mass from galaxy line-of-sight (LOS) velocity dispersion. Assuming perfect membership knowledge, this unrealistic case produces a wide fractional mass error distribution, with a width E=0.87. Interlopers introduce additional scatter, significantly widening the error distribution further (E=2.13). We employ the support distribution machine (SDM) class of algorithms to learn from distributions of data to predict single values. Applied to distributions of galaxy observables such as LOS velocity and projected distance from the cluster center, SDM yields better than a factor-of-two improvement (E=0.67) for the contaminated case. Remarkably, SDM applied to contaminated clusters is better able to recover masses than even the scaling relation approach applied to uncon- taminated clusters. We show that the SDM method more accurately reproduces the cluster mass function, making it a valuable tool for employing cluster observations to evaluate cosmological models.

Measurement and removal of surface contamination

International Nuclear Information System (INIS)

Neider, M.; Tamberg, T.

1990-01-01

This is a critical reappraisal of the sampling factor which is important for indirect contamination measurement. The factor gives the radioactivity collected by means of a wipe sample as a fraction of the total loose radioactivity i.e. without firm adhesion. It is used in national and international standard specifications and stated, frequently with excessive conservatism, as 0.1. Secondly, the standard specifications for the testing and appraisal of surface materials in relation to their decontamination capacity and for testing the effect of decontamination agents hitherto bond and Co-60 and Cs-137 are to be expanded to include radioactive iodine, which is important in nuclear medicine. The selection of optimum surface materials will thus be put on an improved basis. (orig./DG) [de

Deuteron transverse densities in holographic QCD

Energy Technology Data Exchange (ETDEWEB)

Mondal, Chandan [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Indian Institute of Technology Kanpur, Department of Physics, Kanpur (India); Chakrabarti, Dipankar [Indian Institute of Technology Kanpur, Department of Physics, Kanpur (India); Zhao, Xingbo [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China)

2017-05-15

We investigate the transverse charge density in the longitudinally as well as transversely polarized deuteron using the recent empirical description of the deuteron electromagnetic form factors in the framework of holographic QCD. The predictions of the holographic QCD are compared with the results of a standard phenomenological parameterization. In addition, we evaluate GPDs and the gravitational form factors for the deuteron. The longitudinal momentum densities are also investigated in the transverse plane. (orig.)

Mitigating with macrophytes: submersed plants reduce the toxicity of pesticide-contaminated water to zooplankton.

Science.gov (United States)

Brogan, William R; Relyea, Rick A

2013-03-01

In ecotoxicology, appreciation is growing for the influence that ecological interactions have on the toxicity of contaminants, such as insecticides, to sensitive species. Most previous studies, however, have focused on factors that exacerbate insecticide effects on species, while factors that may mitigate these effects have been relatively ignored. In aquatic habitats, a small number of studies have shown that submersed macrophytes can remove some insecticides from the water column via sorption. Although examining sorption dynamics is important for understanding the environmental fate of insecticides, whether and to what extent macrophytes actually mitigate insecticide effects on aquatic species remains unknown. In the present study, the authors examined how much and how quickly several realistic densities of the macrophyte Elodea canadensis decreased the toxicity of the insecticide malathion to Daphnia magna, a keystone aquatic herbivore. To do this, the authors quantified Daphnia survival in outdoor test systems (0.95 L) exposed to a factorial combination of five Elodea densities crossed with five malathion concentrations. The authors discovered that malathion's lethality to Daphnia decreased with increasing Elodea density. Furthermore, the rate at which Elodea reduced malathion's toxicity in the water column increased with macrophyte density. These results provide strong evidence that submersed macrophytes can mitigate the ecological impacts of a popular insecticide and further support that ecological interactions can strongly influence contaminant environmental effects. Copyright © 2013 SETAC.

Toxicological benchmarks for screening potential contaminants of concern for effects on soil and litter invertebrates and heterotrophic process

International Nuclear Information System (INIS)

Will, M.E.; Suter, G.W. II.

1994-09-01

One of the initial stages in ecological risk assessments for hazardous waste sites is the screening of contaminants to determine which of them are worthy of further consideration as open-quotes contaminants of potential concern.close quotes This process is termed open-quotes contaminant screening.close quotes It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to soil- and litter-dwelling invertebrates, including earthworms, other micro- and macroinvertebrates, or heterotrophic bacteria and fungi. This report presents a standard method for deriving benchmarks for this purpose, sets of data concerning effects of chemicals in soil on invertebrates and soil microbial processes, and benchmarks for chemicals potentially associated with United States Department of Energy sites. In addition, literature describing the experiments from which data were drawn for benchmark derivation. Chemicals that are found in soil at concentrations exceeding both the benchmarks and the background concentration for the soil type should be considered contaminants of potential concern

Toxicological benchmarks for screening potential contaminants of concern for effects on soil and litter invertebrates and heterotrophic process

Energy Technology Data Exchange (ETDEWEB)

Will, M.E.; Suter, G.W. II

1994-09-01

One of the initial stages in ecological risk assessments for hazardous waste sites is the screening of contaminants to determine which of them are worthy of further consideration as {open_quotes}contaminants of potential concern.{close_quotes} This process is termed {open_quotes}contaminant screening.{close_quotes} It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to soil- and litter-dwelling invertebrates, including earthworms, other micro- and macroinvertebrates, or heterotrophic bacteria and fungi. This report presents a standard method for deriving benchmarks for this purpose, sets of data concerning effects of chemicals in soil on invertebrates and soil microbial processes, and benchmarks for chemicals potentially associated with United States Department of Energy sites. In addition, literature describing the experiments from which data were drawn for benchmark derivation. Chemicals that are found in soil at concentrations exceeding both the benchmarks and the background concentration for the soil type should be considered contaminants of potential concern.

Demonstration of New Technologies Required for the Treatment of Mixed Waste Contaminated with {ge}260 ppm Mercury

Energy Technology Data Exchange (ETDEWEB)

Morris, M.I.

2002-02-06

The Resource Conservation and Recovery Act (RCRA) defines several categories of mercury wastes, each of which has a defined technology or concentration-based treatment standard, or universal treatment standard (UTS). RCRA defines mercury hazardous wastes as any waste that has a TCLP value for mercury of 0.2 mg/L or greater. Three of these categories, all nonwastewaters, fall within the scope of this report on new technologies to treat mercury-contaminated wastes: wastes as elemental mercury; hazardous wastes with less than 260 mg/kg [parts per million (ppm)] mercury; and hazardous wastes with 260 ppm or more of mercury. While this report deals specifically with the last category--hazardous wastes with 260 ppm or more of mercury--the other two categories will be discussed briefly so that the full range of mercury treatment challenges can be understood. The treatment methods for these three categories are as follows: Waste as elemental mercury--RCRA identifies amalgamation (AMLGM) as the treatment standard for radioactive elemental mercury. However, radioactive mercury condensates from retorting (RMERC) processes also require amalgamation. In addition, incineration (IMERC) and RMERC processes that produce residues with >260 ppm of radioactive mercury contamination and that fail the RCRA toxicity characteristic leaching procedure (TCLP) limit for mercury (0.20 mg/L) require RMERC, followed by AMLGM of the condensate. Waste with <260 ppm mercury--No specific treatment method is specified for hazardous wastes containing <260 ppm. However, RCRA regulations require that such wastes (other than RMERC residues) that exceed a TCLP mercury concentration of 0.20 mg/L be treated by a suitable method to meet the TCLP limit for mercury of 0.025 mg/L. RMERC residues must meet the TCLP value of {ge}0.20 mg/L, or be stabilized and meet the {ge}0.025 mg/L limit. Waste with {ge}260 ppm mercury--For hazardous wastes with mercury contaminant concentrations {ge}260 ppm and RCRA

DEVELOPING STANDARDS FOR ASSESSING ENVIRONMENTAL CHEMICAL, PHYSICAL, AND BIOLOGICAL STRESSORS THROUGH ASTM COMMITTEE E47: A PAST FOUNDATION OF PROVEN STANDARDS, A FUTURE OF GREAT POTENTIAL AND OPPORTUNITY

Science.gov (United States)

Development of standards associated with assessing the bioavailability of contaminants in sediment will be used as a case study for how standards have been developed through Committee E47. In 1987, Committee E47 established Subcommittee E47.03 on Sediment Assessment and Toxicity....

Procedure for Uranium-Molybdenum Density Measurements and Porosity Determination

Energy Technology Data Exchange (ETDEWEB)

Prabhakaran, Ramprashad [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Devaraj, Arun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Joshi, Vineet V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lavender, Curt A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-08-13

The purpose of this document is to provide guidelines for preparing uranium-molybdenum (U-Mo) specimens, performing density measurements, and computing sample porosity. Typical specimens (solids) will be sheared to small rectangular foils, disks, or pieces of metal. A mass balance, solid density determination kit, and a liquid of known density will be used to determine the density of U-Mo specimens using the Archimedes principle. A standard test weight of known density would be used to verify proper operation of the system. By measuring the density of a U-Mo sample, it is possible to determine its porosity.

Facilities for treatment of radioactive contaminated water in nuclear power plants

International Nuclear Information System (INIS)

1981-02-01

The standard applies to processes applied in facilities for treatment of radioactive contaminated water in nuclear power plants with LWR- and HTR-type reactors. It does not apply to the treatment of concentrates obtained in the decontamination of water. (orig.) [de

Development of a standardized differential-reflective bioassay for microbial pathogens

Science.gov (United States)

Wilhelm, Jay; Auld, J. R. X.; Smith, James E.

2008-04-01

This research examines standardizing a method for the rapid/semi-automated identification of microbial contaminates. It introduces a method suited to test for food/water contamination, serology, urinalysis and saliva testing for any >1 micron sized molecule that can be effectively bound to an identifying marker with exclusivity. This optical biosensor method seeks to integrate the semi-manual distribution of a collected sample onto a "transparent" substrate array of binding sites that will then be applied to a standard optical data disk and run for analysis. The detection of most microbe species is possible in this platform because the relative scale is greater than the resolution of the standard-scale digital information on a standard CD or DVD. This paper explains the critical first stage in the advance of this detection concept. This work has concentrated on developing the necessary software component needed to perform highly sensitive small-scale recognition using the standard optical disk as a detection platform. Physical testing has made significant progress in demonstrating the ability to utilize a standard optical drive for the purposes of micro-scale detection through the exploitation of CIRC error correction. Testing has also shown a definable trend in the optimum scale and geometry of micro-arrayed attachment sites for the technology's concept to reach achievement.

The long-term problems of contaminated land: Sources, impacts and countermeasures

Energy Technology Data Exchange (ETDEWEB)

Baes, C.F. III

1986-11-01

This report examines the various sources of radiological land contamination; its extent; its impacts on man, agriculture, and the environment; countermeasures for mitigating exposures; radiological standards; alternatives for achieving land decontamination and cleanup; and possible alternatives for utilizing the land. The major potential sources of extensive long-term land contamination with radionuclides, in order of decreasing extent, are nuclear war, detonation of a single nuclear weapon (e.g., a terrorist act), serious reactor accidents, and nonfission nuclear weapons accidents that disperse the nuclear fuels (termed ''broken arrows'').

Analysis of legal arrangements concerning the control and monitoring of the contamination of soils, food products and commercial products in Belarus

International Nuclear Information System (INIS)

Bataille, C.; Crouail, P.

2005-01-01

After having recalled the management of emergency from April to May 1986, this report describes some aspects of the post-accident management in Soviet Union from June 1986 to 1991: dose limits and zoning, farming practices, consumption standards, commercialization standards. It describes the legal context implemented in Belarus from 1991 (two laws addressed the legal status of contaminated areas and the protection of people affected by the Chernobyl accident), and the evolutions since 1991 in terms of soil contamination and zoning, consumption and commercialization standards

Is the use of low-pressure pulsatile lavage for pressure ulcer management associated with environmental contamination with Acinetobacter baumannii?

Science.gov (United States)

Ho, Chester H; Johnson, Tova; Miklacic, Joan; Donskey, Curtis J

2009-10-01

Ho CH, Johnson T, Miklacic J, Donskey CJ. Is the use of low-pressure pulsatile lavage for pressure ulcer management associated with environmental contamination with Acinetobacter baumannii? To determine the extent of environmental contamination associated with low-pressure pulsatile lavage of stage III or IV pressure ulcers in patients with spinal cord injury (SCI) when routine infection control precautions are used for wounds colonized or infected with Acinetobacter baumannii. Prospective investigation in which pressure ulcer cultures and environmental cultures were obtained before and after low-pressure pulsatile lavage treatment, and before and after regular dressing changes. Environmental cultures included the patient's bedrail and settle plates placed 0.6, 1.5, and 2.4m from the wound to assess airborne spread of A. baumannii. SCI inpatient unit in a Department of Veterans Affairs Medical Center. Inpatients (N=15) with SCI receiving daily low-pressure pulsatile lavage treatment for stage III or IV pressure ulcers with standard dressing change, as well as regular dressing changes without low-pressure pulsatile lavage at other times of the day. Standard, regular dressing changes and dressing changes with low-pressure pulsatile lavage. Comparison of frequency of environmental contamination with A. baumannii associated with low-pressure pulsatile lavage versus regular dressing changes. Of the 15 SCI inpatients meeting inclusion criteria, 9 (60%) grew A. baumannii from their wounds. Of the 9 patients with wound cultures positive for A. baumannii, only 1 (11%) had environmental contamination with this organism after performance of low-pressure pulsatile lavage, and the same patient had environmental contamination after a standard dressing change. The antibiotic susceptibility patterns of the wound and environmental A. baumannii isolates were identical. Low-pressure pulsatile lavage using the infection control methods described is not associated with an increased

Ecotoxicological hazard assessment of hydrocarbon contaminated soils: A case study

International Nuclear Information System (INIS)

Roy, Y.; Pauwels, S.J.; Chasse, R.

1994-01-01

The Ecotoxicological Hazard Assessment (EHA) developed by the Quebec Ministry of Environment and Wildlife was used as part of the management scheme of contaminated soils from a former refinery. The study consists of assessing five types of soils (reference, heavily contaminated, slightly contaminated, thermally-treated, and biotreated) to determine their relative intrinsic hazard. During the exploratory activities a series of ten assessment endpoints where identified to support this typical EHA. During SOURCE characterization, the physicochemical make-up of the soils is described and the presence and concentrations of priority pollutants is determined. During FATE characterization, the potential for bioconcentration, mobility, and persistence of pollutants is determined. During EFFECTS characterization, the soils and their leachates are tested using standard terrestrial and aquatic bioassays. The data from the toxicological and analytical testing program are evaluated semi-quantitatively on the basis of a scoring system developed by consensus. The discussion will highlight how data are used within an EHA to streamline the decision-making process regarding the follow-up cleanup and disposal of contaminated soils

Correlates of Harlequin Duck densities during winter in Prince William Sound, Alaska

Science.gov (United States)

Esler, Daniel N.; Bowman, Timothy D.; Dean, T.A.; O'Clair, Charles E.; Jewett, S.C.; McDonald, L.L.

2000-01-01

We evaluated relationships of Harlequin Duck (Histrionicus histrionicus) densities to habitat attributes, history of habitat contamination by the 1989 Exxon Valdez oil spill, and prey biomass density and abundance during winters 1995-1997 in Prince William Sound, Alaska. Habitat features that explained variation in duck densities included distance to streams and reefs, degree of exposure to wind and wave action, and dominant substrate type. After accounting for these effects, densities were lower in oiled than unoiled areas, suggesting that population recovery from the oil spill was not complete, due either to lack of recovery from initial oil spill effects or continuing deleterious effects. Prey biomass density and abundance were not strongly related to duck densities after accounting for habitat and area effects. Traits of Harlequin Ducks that reflect their affiliation with naturally predictable winter habitats, such as strong site fidelity and intolerance of increased energy costs, may make their populations particularly vulnerable to chronic oil spill effects and slow to recover from population reductions, which may explain lower densities than expected on oiled areas nearly a decade following the oil spill.

Modeling bacterial contamination of fuel ethanol fermentation.

Science.gov (United States)

Bischoff, Kenneth M; Liu, Siqing; Leathers, Timothy D; Worthington, Ronald E; Rich, Joseph O

2009-05-01

The emergence of antibiotic-resistant bacteria may limit the effectiveness of antibiotics to treat bacterial contamination in fuel ethanol plants, and therefore, new antibacterial intervention methods and tools to test their application are needed. Using shake-flask cultures of Saccharomyces cerevisiae grown on saccharified corn mash and strains of lactic acid bacteria isolated from a dry-grind ethanol facility, a simple model to simulate bacterial contamination and infection was developed. Challenging the model with 10(8) CFU/mL Lactobacillus fermentum decreased ethanol yield by 27% and increased residual glucose from 6.2 to 45.5 g/L. The magnitude of the effect was proportional to the initial bacterial load, with 10(5) CFU/mL L. fermentum still producing an 8% decrease in ethanol and a 3.2-fold increase in residual glucose. Infection was also dependent on the bacterial species used to challenge the fermentation, as neither L. delbrueckii ATCC 4797 nor L. amylovorus 0315-7B produced a significant decrease in ethanol when inoculated at a density of 10(8) CFU/mL. In the shake-flask model, treatment with 2 microg/mL virginiamycin mitigated the infection when challenged with a susceptible strain of L. fermentum (MIC for virginiamycin model may find application in developing new antibacterial agents and management practices for use in controlling contamination in the fuel ethanol industry. Copyright 2008 Wiley Periodicals, Inc.

OPEN AIR DEMOLITION OF FACILITIES HIGHLY CONTAMINATED WITH PLUTONIUM

International Nuclear Information System (INIS)

LLOYD, E.R.

2007-01-01

The demolition of highly contaminated plutonium buildings usually is a long and expensive process that involves decontaminating the building to near free- release standards and then using conventional methods to remove the structure. It doesn't, however, have to be that way. Fluor has torn down buildings highly contaminated with plutonium without excessive decontamination. By removing the select source term and fixing the remaining contamination on the walls, ceilings, floors, and equipment surfaces; open-air demolition is not only feasible, but it can be done cheaper, better (safer), and faster. Open-air demolition techniques were used to demolish two highly contaminated buildings to slab-on-grade. These facilities on the Department of Energy's Hanford Site were located in, or very near, compounds of operating nuclear facilities that housed hundreds of people working on a daily basis. To keep the facilities operating and the personnel safe, the projects had to be creative in demolishing the structures. Several key techniques were used to control contamination and keep it within the confines of the demolition area: spraying fixatives before demolition; applying fixative and misting with a fine spray of water as the buildings were being taken down; and demolishing the buildings in a controlled and methodical manner. In addition, detailed air-dispersion modeling was done to establish necessary building and meteorological conditions and to confirm the adequacy of the proposed methods. Both demolition projects were accomplished without any spread of contamination outside the modest buffer areas established for contamination control. Furthermore, personnel exposure to radiological and physical hazards was significantly reduced by using heavy equipment rather than ''hands on'' techniques

Cumulative sum quality control for calibrated breast density measurements

International Nuclear Information System (INIS)

Heine, John J.; Cao Ke; Beam, Craig

2009-01-01

Purpose: Breast density is a significant breast cancer risk factor. Although various methods are used to estimate breast density, there is no standard measurement for this important factor. The authors are developing a breast density standardization method for use in full field digital mammography (FFDM). The approach calibrates for interpatient acquisition technique differences. The calibration produces a normalized breast density pixel value scale. The method relies on first generating a baseline (BL) calibration dataset, which required extensive phantom imaging. Standardizing prospective mammograms with calibration data generated in the past could introduce unanticipated error in the standardized output if the calibration dataset is no longer valid. Methods: Sample points from the BL calibration dataset were imaged approximately biweekly over an extended timeframe. These serial samples were used to evaluate the BL dataset reproducibility and quantify the serial calibration accuracy. The cumulative sum (Cusum) quality control method was used to evaluate the serial sampling. Results: There is considerable drift in the serial sample points from the BL calibration dataset that is x-ray beam dependent. Systematic deviation from the BL dataset caused significant calibration errors. This system drift was not captured with routine system quality control measures. Cusum analysis indicated that the drift is a sign of system wear and eventual x-ray tube failure. Conclusions: The BL calibration dataset must be monitored and periodically updated, when necessary, to account for sustained system variations to maintain the calibration accuracy.

Cumulative sum quality control for calibrated breast density measurements

Energy Technology Data Exchange (ETDEWEB)

Heine, John J.; Cao Ke; Beam, Craig [Cancer Prevention and Control Division, Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, Florida 33612 (United States); Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, 1603 W. Taylor St., Chicago, Illinois 60612 (United States)

2009-12-15

Purpose: Breast density is a significant breast cancer risk factor. Although various methods are used to estimate breast density, there is no standard measurement for this important factor. The authors are developing a breast density standardization method for use in full field digital mammography (FFDM). The approach calibrates for interpatient acquisition technique differences. The calibration produces a normalized breast density pixel value scale. The method relies on first generating a baseline (BL) calibration dataset, which required extensive phantom imaging. Standardizing prospective mammograms with calibration data generated in the past could introduce unanticipated error in the standardized output if the calibration dataset is no longer valid. Methods: Sample points from the BL calibration dataset were imaged approximately biweekly over an extended timeframe. These serial samples were used to evaluate the BL dataset reproducibility and quantify the serial calibration accuracy. The cumulative sum (Cusum) quality control method was used to evaluate the serial sampling. Results: There is considerable drift in the serial sample points from the BL calibration dataset that is x-ray beam dependent. Systematic deviation from the BL dataset caused significant calibration errors. This system drift was not captured with routine system quality control measures. Cusum analysis indicated that the drift is a sign of system wear and eventual x-ray tube failure. Conclusions: The BL calibration dataset must be monitored and periodically updated, when necessary, to account for sustained system variations to maintain the calibration accuracy.

How Clean Are Hotel Rooms? Part II: Examining the Concept of Cleanliness Standards.

Science.gov (United States)

Almanza, Barbara A; Kirsch, Katie; Kline, Sheryl Fried; Sirsat, Sujata; Stroia, Olivia; Choi, Jin Kyung; Neal, Jay

2015-01-01

Hotel room cleanliness is based on observation and not on microbial assessment even though recent reports suggest that infections may be acquired while staying in hotel rooms. Exploratory research in the first part of the authors' study was conducted to determine if contamination of hotel rooms occurs and whether visual assessments are accurate indicators of hotel room cleanliness. Data suggested the presence of microbial contamination that was not reflective of visual assessments. Unfortunately, no standards exist for interpreting microbiological data and other indicators of cleanliness in hotel rooms. The purpose of the second half of the authors' study was to examine cleanliness standards in other industries to see if they might suggest standards in hotels. Results of the authors' study indicate that standards from other related industries do not provide analogous criteria, but do provide suggestions for further research.

Evaluation of the Level of air Microbial Contamination in some ...

African Journals Online (AJOL)

The level of air microbial contamination in some teaching hospitals waste dump site in South Eastern Nigeria was evaluated using the standard microbiological techniques. Passive air sampling was performed using settle plates. The microbial load of the air around the hospitals waste dumpsite, showed high microbial load ...

Control System Radioactive Contamination in Food Samples in Poland

International Nuclear Information System (INIS)

Grabowski, D.; Kurowski, W.; Muszynski, W.; Rubel, B.; Smagala, G.; Swietochowska, J.

2001-01-01

Full text: The analyses of the level of radioactive contamination in food samples are carried out by the Service for Measurements of Radioactive Contamination (SMRC) in Poland. The Service was brought into existence in 1961. The Service comprises of a network of measurement stations and the Centre of Radioactive Contamination Measurements (CRCM). The duty of the Centre is being executed by the Central Laboratory for Radiological Protection (CLRP). The uniform methods of sampling are used in measurement stations. All important foodstuff: milk, meat, vegetables, fruit, cereals are controlled in the Service stations. The radiochemical and spectrometric methods are used to determine the activity of radioactive isotopes. The standard equipment of the measurement station is the measurement system type SAPOS-90 and multichannel analyser with scintillation or germanium detector. The structure of the Service, kinds of samples tested by each station, program of sampling in normal and during accident situation are presented in this paper. (author)

Pollution of soil and groundwater from infiltration of highly contaminated stormwater - a case study

DEFF Research Database (Denmark)

Mikkelsen, P.S.; Häfliger, M.; Ochs, M.

1997-01-01

and subsurface sediments and some even exceeded guidelines fixed to preserve the fertility of soil. However, the contamination decreased rapidly with depth. None of the measured metal concentrations in simulated soil solutions exceeded defined drinking water quality standards. Surprisingly, the surface......A surface and a sub-surface infiltration system that received runoff water from trafficked roads for several decades was dug up and the contamination with heavy metals, PAH and AOX was investigated. Most measured solid phase concentrations exceeded background concentrations in nearby surface soils...... contamination due to stormwater infiltration, but highlights that well absorbable contaminants readily available in urban stormwater runoff eventually build up in surface soils and sub-surface sediments to environmentally critical concentration levels. Thus, on the one hand stormwater infiltration systems may...

Removal of Microbial Contamination from Surface by Plasma

Science.gov (United States)

Feng, Xinxin; Liu, Hongxia; Shen, Zhenxing; Wang, Taobo

2018-01-01

Microbial contamination is closely associated with human and environmental health, they can be tested on food surfaces, medical devices, packing material and so on. In this paper the removal of the microbial contamination from surface using plasma treatment is investigated. The Escherichia coli (E. coli) has been chosen as a bio-indicator enabling to evaluate the effect of plasma assisted microbial inactivation. Oxygen gas was as the working gas. The plasma RF power, plasma exposition time, gas flow and the concentration of organic pollutant were varied in order to see the effect of the plasma treatment on the Gram-negative germ removal. After the treatment, the microbial abatement was evaluated by the standard plate count method. This proved a positive effect of the plasma treatment on Gram-negative germ removal. The kinetics and mathematical model of removal were studied after plasma treatment, and then the removing course of E. coli was analyzed. This work is meaningful for deepening our understanding of the fundamental scientific principles regarding microbial contamination from surface by plasma.

Antimicrobial Properties of Selected Copper Alloys on Staphylococcus aureus and Escherichia coli in Different Simulations of Environmental Conditions: With vs. without Organic Contamination.

Science.gov (United States)

Różańska, Anna; Chmielarczyk, Agnieszka; Romaniszyn, Dorota; Sroka-Oleksiak, Agnieszka; Bulanda, Małgorzata; Walkowicz, Monika; Osuch, Piotr; Knych, Tadeusz

2017-07-20

Background: Hospital equipment made from copper alloys can play an important role in complementing traditional methods of disinfection. Aims of the study: The aim of this study was to assess the dynamics of the antimicrobial properties of selected copper alloys in different simulations of environmental conditions (with organic contamination vs. without organic contamination), and to test alternatives to the currently used testing methods. Materials and Methods: A modification of Japanese standard JIS Z 2801 as well as Staphylococcus aureus (SA) and Escherichia coli (EC) suspended in NaCl vs. tryptic soy broth (TSB) were used in tests performed on seven commonly used copper alloys, copper, and stainless steel. Results: A much faster reduction of the bacterial suspension was observed for the inoculum prepared in NaCl than in TSB. A faster reduction for EC than for SA was observed in the inoculum prepared in NaCl. The opposite results were found for the inoculum based on TSB. A significant correlation between the copper concentration in the copper alloys and the time and degree of bacterial suspension reduction was only observed in the case of EC. Conclusions: This study confirmed the antimicrobial properties of copper alloys, and additionally showed that Staphylococcus aureus was more resistant than Escherichia coli in the variant of the experiment without organic contamination. However, even for SA, a total reduction of the bacterial inoculum's density took no longer than 2 h. Under conditions simulating organic contamination, all of the tested alloys were shown to have bactericidal or bacteriostatic properties, which was contrary to the results from stainless steel.

Radiation Safety Analysis In The NFEC For Assessing Possible Implementation Of The ICRP-60 Standard

International Nuclear Information System (INIS)

Yowono, I.

1998-01-01

Radiation safety analysis of the 3 facilities in the nuclear fuel element center (NFEC) for assessing possible implementation of the ICRP-60 standard has been done. The analysis has covered the radiation dose received by workers, dose rate in the working area, surface contamination level, air contamination level and the level of radioactive gas release to the environment. The analysis has been based on BATAN regulation and ICRP-60 standard. The result of the analysis has showed that the highest radiation dose received has been found to be only around 15% of the set value in the ICRP-60 standard and only 6% of the set value in the BATAN regulation. Thus the ICRP-60 as radiation safety standard could be implemented without changing the laboratory design

Unsaturated zone leaching models for assessing risk to groundwater of contaminated sites

DEFF Research Database (Denmark)

Troldborg, Mads; Binning, Philip John; Nielsen, Signe

2009-01-01

and aqueous phase contaminant transport equation. The equation has the same general form as the standard advection-diffusion equation for which many analytical solutions have been derived. Four new analytical solutions are developed using this approach: a three-dimensional solution accounting for infiltration......, lateral gas diffusion, sorption and degradation; a simple one-dimensional screening model, and two one-dimensional radial gas diffusion models for use in simulating volatile organic contaminant diffusion in unsaturated soils with an impermeable cover. The models show that both degradation and diffusion...

Lead isotope analyses of standard rock samples

International Nuclear Information System (INIS)

Koide, Yoshiyuki; Nakamura, Eizo

1990-01-01

New results on lead isotope compositions of standard rock samples and their analytical procedures are reported. Bromide form anion exchange chromatography technique was adopted for the chemical separation lead from rock samples. The lead contamination during whole analytical procedure was low enough to determine lead isotope composition of common natural rocks. Silica-gel activator method was applied for emission of lead ions in the mass spectrometer. Using the data reduction of 'unfractionated ratios', we obtained good reproducibility, precision and accuracy on lead isotope compositions of NBS SRM. Here we present new reliable lead isotope compositions of GSJ standard rock samples and USGS standard rock, BCR-1. (author)

High Efficiency, High Density Terrestrial Panel. [for solar cell modules

Science.gov (United States)

Wohlgemuth, J.; Wihl, M.; Rosenfield, T.

1979-01-01

Terrestrial panels were fabricated using rectangular cells. Packing densities in excess of 90% with panel conversion efficiencies greater than 13% were obtained. Higher density panels can be produced on a cost competitive basis with the standard salami panels.

Human islet viability and function is maintained during high density shipment in silicone rubber membrane vessels

Science.gov (United States)

Kitzmann, Jennifer P; Pepper, Andrew R; Lopez, Boris G; Pawlick, Rena; Kin, Tatsuya; O’Gorman, Doug; Mueller, Kathryn R; Gruessner, Angelika C; Avgoustiniatos, Efstathios S; Karatzas, Theodore; Szot, Greg L; Posselt, Andrew M; Stock, Peter G; Wilson, John R; Shapiro, AM; Papas, Klearchos K

2014-01-01

The shipment of human islets from processing centers to distant laboratories is beneficial for both research and clinical applications. The maintenance of islet viability and function in transit is critically important. Gas-permeable silicone rubber membrane (SRM) vessels reduce the risk of hypoxia-induced death or dysfunction during high-density islet culture or shipment. SRM vessels may offer additional advantages: they are cost-effective (fewer flasks, less labor needed), safer (lower contamination risk), and simpler (culture vessel can also be used for shipment). Human islets(IE) were isolated from two manufacturing centers and shipped in 10cm2 surface area SRM vessels in temperature and pressure controlled containers to a distant center following at least two days of culture (n = 6). Three conditions were examined: low density (LD), high density (HD), and a micro centrifuge tube negative control (NC). LD was designed to mimic the standard culture density for human islet preparations (200 IE/cm2), while HD was designed to have a 20-fold higher tissue density, which would enable the culture of an entire human isolation in 1–3 vessels. Upon receipt, islets were assessed for viability, measured by oxygen consumption rate normalized to DNA content (OCR/DNA), and quantity, measured by DNA, and, when possible, potency and function with dynamic glucose-stimulated insulin secretion (GSIS) measurements and transplants in immunodeficient B6 rag mice. Post-shipment OCR/DNA was not reduced in HD versus LD, and was substantially reduced in the NC condition. HD islets exhibited normal function post-shipment. Based on the data we conclude that entire islet isolations (up to 400,000 IE) may be shipped using a single, larger SRM vessel with no negative effect on viability and ex vivo and in vivo function. PMID:25131090

Removal of trace metal contaminants from potable water by electrocoagulation

Science.gov (United States)

Heffron, Joe; Marhefke, Matt; Mayer, Brooke K.

2016-06-01

This study investigated the effects of four operational and environmental variables on the removal of trace metal contaminants from drinking water by electrocoagulation (EC). Removal efficiencies for five metals (arsenic, cadmium, chromium, lead and nickel) were compared under varying combinations of electrode material, post-treatment, water composition and pH. Iron electrodes out-performed aluminum electrodes in removing chromium and arsenic. At pH 6.5, aluminum electrodes were slightly more effective at removing nickel and cadmium, while at pH 8.5, iron electrodes were more effective for these metals. Regardless of electrode, cadmium and nickel removal efficiencies were higher at pH 8.5 than at pH 6.5. Post-EC treatment using membrane filtration (0.45 μm) enhanced contaminant removal for all metals but nickel. With the exception of lead, all metals exhibited poorer removal efficiencies as the ionic strength of the background electrolyte increased, particularly in the very high-solids synthetic groundwaters. Residual aluminum concentrations were lowest at pH 6.5, while iron residuals were lowest in low ionic strength waters. Both aluminum and iron residuals required post-treatment filtration to meet drinking water standards. EC with post-treatment filtration appears to effectively remove trace metal contaminants to potable water standards, but both reactor and source water parameters critically impact removal efficiency.

Environmental contamination with Toxocara spp. eggs in public parks and playground sandpits of Greater Lisbon, Portugal.

NARCIS (Netherlands)

Otero, David; Alho, Ana M; Nijsse, Rolf; Roelfsema, Jeroen; Overgaauw, Paul; Madeira de Carvalho, Luís

2018-01-01

Toxocarosis is a zoonotic parasitic disease transmitted from companion animals to humans. Environmental contamination with Toxocara eggs is considered to be the main source of human infections. In Portugal, knowledge regarding the current situation, including density, distribution and environmental

Environmental contamination with Toxocara spp. eggs in public parks and playground sandpits of Greater Lisbon, Portugal

NARCIS (Netherlands)

Otero, David; Alho, Ana M.; Nijsse, Rolf; Roelfsema, Jeroen; Overgaauw, Paul; Madeira de Carvalho, Luís

2018-01-01

Toxocarosis is a zoonotic parasitic disease transmitted from companion animals to humans. Environmental contamination with Toxocara eggs is considered to be the main source of human infections. In Portugal, knowledge regarding the current situation, including density, distribution and environmental

Contaminant flow and transport simulation in cracked porous media using locally conservative schemes

KAUST Repository

Song, Pu

2012-10-25

The purpose of this paper is to analyze some features of contaminant flow passing through cracked porous medium, such as the influence of fracture network on the advection and diffusion of contaminant species, the impact of adsorption on the overall transport of contaminant wastes. In order to precisely describe the whole process, we firstly build the mathematical model to simulate this problem numerically. Taking into consideration of the characteristics of contaminant flow, we employ two partial differential equations to formulate the whole problem. One is flow equation; the other is reactive transport equation. The first equation is used to describe the total flow of contaminant wastes, which is based on Darcy law. The second one will characterize the adsorption, diffusion and convection behavior of contaminant species, which describes most features of contaminant flow we are interested in. After the construction of numerical model, we apply locally conservative and compatible algorithms to solve this mathematical model. Specifically, we apply Mixed Finite Element (MFE) method to the flow equation and Discontinuous Galerkin (DG) method for the transport equation. MFE has a good convergence rate and numerical accuracy for Darcy velocity. DG is more flexible and can be used to deal with irregular meshes, as well as little numerical diffusion. With these two numerical means, we investigate the sensitivity analysis of different features of contaminant flow in our model, such as diffusion, permeability and fracture density. In particular, we study K d values which represent the distribution of contaminant wastes between the solid and liquid phases. We also make omparisons of two different schemes and discuss the advantages of both methods. © 2012 Global Science Press.

Production of low oxygen contamination orthorhombic Ti-Al-Nb intermetallic foil

International Nuclear Information System (INIS)

Gill, S.C.; Peters, J.A.; Blatter, P.; Jaquet, J.C.; Morris, M.A.

1996-01-01

Aerospace industries continue the search for high performance materials, and recent years have seen rapid developments being made in the capabilities of Ti-Al based intermetallic alloys. Interest in these alloys is caused by their attractive combination of strength and density, but major drawbacks include brittleness at low temperature and sensitivity to interstitial contamination. Development of a relatively new class of alloys was stimulated in 1988 by the discovery of Banerjee et al. of a Ti-Al-Nb orthorhombic (O) phase based on the Ti 2 AlNb composition. Some important applications for these alloys require the use of foil ( 2 phase and leads to material embrittlement. ELIT (Extra Low Interstitial Transfer) pack-rolling, developed by Sulzer Innotec, offers a technique to avoid oxygen contamination

Standards for deuterium analysis requirements of heavy water plants (Preprint No. CA-1)

Energy Technology Data Exchange (ETDEWEB)

Rathi, B N; Gopalakrishnan, V T; Alphonse, K P; Pawar, P L; Sadhukhan, H K [Bhabha Atomic Research Centre, Bombay (India). Heavy Water Div.

1989-04-01

Accurate analysis of deuterium, covering the entire range, is of great importance in production of heavy water. Most of the methods for determination of deuterium in gas or liquid samples require appropriate standards. Since density of pure protium oxide and pure deuterium oxide has been determined very accurately by a large number of workers and density of mixtures of H{sub 2}O and D{sub 2}O follows a linear relation, it is possible to use accurate density determination for measurement of deuterium content. Float method for density measurements was improved further and used for the preparation of primary heavy water standards in high and low deuterium ranges. Heavy water plant laboratories require gas standards (ammonia synthesis gas matrix), in addition to low deuterium water standards, for calibration of mass spectrometers. SLAP (Standard Light Antarctic Precipitation, D/D+H = 89.02+-0.05ppm) and SMOW (Standard Mean Ocean Water, D/D+H =155.76+-0.05ppm) available from IAEA, Vienna, along with water practically free from deuterium, were used as standards to prepare secondary liquid standards. These secondary standards were subsequently reduced and mixed with pure nitrogen to obtain D/D+H standards in syngas matrix. (author). 8 refs., 2 figs.

Emerging Contaminants and Federal Facility Contaminants of Concern

Science.gov (United States)

This page links to fact sheets summarizing contaminants of concern and emerging contaminants that present unique issues and challenges to the environmental community in general and to FFRRO in particular.

Underwater Coatings for Contamination Control

International Nuclear Information System (INIS)

Julia L. Tripp; Kip Archibald; Ann-Marie Phillips; Joseph Campbell

2004-01-01

The Idaho National Engineering and Environmental Laboratory (INEEL) is deactivating several fuel storage basins. Airborne contamination is a concern when the sides of the basins are exposed and allowed to dry during water removal. One way of controlling this airborne contamination is to fix the contamination in place while the pool walls are still submerged. There are many underwater coatings available on the market that are used in marine, naval and other applications. A series of tests were run to determine whether the candidate underwater fixatives are easily applied and adhere well to the substrates (pool wall materials) found in INEEL fuel pools. The four pools considered included (1) Test Area North (TAN-607) with epoxy painted concrete walls; (2) Idaho Nuclear Technology and Engineering Center (INTEC) (CPP-603) with bare concrete walls; (3) Materials Test Reactor (MTR) Canal with stainless steel lined concrete walls; and (4) Power Burst Facility (PBF-620) with stainless steel lined concrete walls on the bottom and epoxy painted carbon steel lined walls on the upper portions. Therefore, the four materials chosen for testing included bare concrete, epoxy painted concrete, epoxy painted carbon steel, and stainless steel. The typical water temperature of the pools varies from 55 F to 80 F dependent on the pool and the season. These tests were done at room temperature. The following criteria were used during this evaluation. The underwater coating must: (1) Be easy to apply; (2) Adhere well to the four surfaces of interest; (3) Not change or have a negative impact on water chemistry or clarity; (4) Not be hazardous in final applied form; and (5) Be proven in other underwater applications. In addition, it is desirable for the coating to have a high pigment or high cross-link density to prevent radiation from penetrating. This paper will detail the testing completed and the test results. A proprietary two-part, underwater epoxy owned by S. G. Pinney and Associates

Performance of passive samplers for monitoring estuarine water column concentrations: 2. Emerging contaminants.

Science.gov (United States)

Perron, Monique M; Burgess, Robert M; Suuberg, Eric M; Cantwell, Mark G; Pennell, Kelly G

2013-10-01

Measuring dissolved concentrations of emerging contaminants, such as polybrominated diphenyl ethers (PBDEs) and triclosan, can be challenging due to their physicochemical properties resulting in low aqueous solubilities and association with particles. Passive sampling methods have been applied to assess dissolved concentrations in water and sediments primarily for legacy contaminants. Although the technology is applicable to some emerging contaminants, the use of passive samplers with emerging contaminants is limited. In the present study, the performance of 3 common passive samplers was evaluated for sampling PBDEs and triclosan. Passive sampling polymers included low-density polyethylene (PE) and polyoxymethylene (POM) sheets, and polydimethylsiloxane (PDMS)-coated solid-phase microextraction (SPME) fibers. Dissolved concentrations were calculated using measured sampler concentrations and laboratory-derived partition coefficients. Dissolved tri-, tetra-, and pentabrominated PBDE congeners were detected at several of the study sites at very low pg/L concentrations using PE and POM. Calculated dissolved water concentrations of triclosan ranged from 1.7 ng/L to 18 ng/L for POM and 8.8 ng/L to 13 ng/L for PE using performance reference compound equilibrium adjustments. Concentrations in SPME were not reported due to lack of detectable chemical in the PDMS polymer deployed. Although both PE and POM were found to effectively accumulate emerging contaminants from the water column, further research is needed to determine their utility as passive sampling devices for emerging contaminants. © 2013 SETAC.

Spin-adapted open-shell time-dependent density functional theory. III. An even better and simpler formulation.

Science.gov (United States)

Li, Zhendong; Liu, Wenjian

2011-11-21

The recently proposed spin-adapted time-dependent density functional theory (S-TD-DFT) [Z. Li and W. Liu, J. Chem. Phys. 133, 064106 (2010)] resolves the spin-contamination problem in describing singly excited states of high spin open-shell systems. It is an extension of the standard restricted open-shell Kohn-Sham-based TD-DFT which can only access those excited states due to singlet-coupled single excitations. It is also far superior over the unrestricted Kohn-Sham-based TD-DFT (U-TD-DFT) which suffers from severe spin contamination for those excited states due to triplet-coupled single excitations. Nonetheless, the accuracy of S-TD-DFT for high spin open-shell systems is still inferior to TD-DFT for well-behaved closed-shell systems. The reason can be traced back to the violation of the spin degeneracy conditions (SDC) by approximate exchange-correlation (XC) functionals. Noticing that spin-adapted random phase approximation (S-RPA) can indeed maintain the SDC by virtue of the Wigner-Eckart theorem, a hybrid ansatz combining the good of S-TD-DFT and S-RPA can immediately be envisaged. The resulting formalism, dubbed as X-TD-DFT, is free of spin contamination and can also be viewed as a S-RPA correction to the XC kernel of U-TD-DFT. Compared with S-TD-DFT, X-TD-DFT leads to much improved results for the low-lying excited states of, e.g., N(2)(+), yet with much reduced computational cost. Therefore, X-TD-DFT can be recommended for routine calculations of excited states of high spin open-shell systems.

Means to remove electrode contamination effect of Langmuir probe measurement in space

Energy Technology Data Exchange (ETDEWEB)

Oyama, K.-I.; Lee, C. H.; Fang, H. K.; Cheng, C. Z. [Plasma and Space Science Center, National Cheng Kung University, No.1 Ta-Hsueh Rd., Tainan 70101, Taiwan (China)

2012-05-15

Precaution to remove the serious effect of electrode contamination in Langmuir probe experiments has not been taken in many space measurements because the effect is either not understood or ignored. We stress here that one should pay extra attention to the electrode contamination effect to get accurate and reliable plasma measurements so that the long time effort for sounding rocket/satellite missions does not end in vain or becomes less fruitful. In this paper, we describe two main features of voltage-current characteristic curves associated with the contaminated Langmuir probe, which are predicted from the equivalent circuit model, which we proposed in 1970's. We then show that fast sweeping dc Langmuir probes can give reliable results in the steady state regime. The fast sweeping probe can also give reliable results in transient situations such as satellite moves through plasma bubble in the ionosphere where the electron density drastically changes. This fact was first confirmed in our laboratory experiment.

40 CFR 141.62 - Maximum contaminant levels for inorganic contaminants.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Maximum contaminant levels for inorganic contaminants. 141.62 Section 141.62 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Water Regulations: Maximum Contaminant Levels and Maximum Residual Disinfectant Levels § 141.62 Maximum...

Radioactive surface contamination monitors

International Nuclear Information System (INIS)

Aoyama, Kei; Minagoshi, Atsushi; Hasegawa, Toru

1994-01-01

To reduce radiation exposure and prevent contamination from spreading, each nuclear power plant has established a radiation controlled area. People and articles out of the controlled area are checked for the surface contamination of radioactive materials with surface contamination monitors. Fuji Electric has repeatedly improved these monitors on the basis of user's needs. This paper outlines typical of a surface contamination monitor, a personal surface contamination monitor, an article surface contamination monitor and a laundry monitor, and the whole-body counter of an internal contamination monitor. (author)

Simulating QCD at finite density

CERN Document Server

de Forcrand, Philippe

2009-01-01

In this review, I recall the nature and the inevitability of the "sign problem" which plagues attempts to simulate lattice QCD at finite baryon density. I present the main approaches used to circumvent the sign problem at small chemical potential. I sketch how one can predict analytically the severity of the sign problem, as well as the numerically accessible range of baryon densities. I review progress towards the determination of the pseudo-critical temperature T_c(mu), and towards the identification of a possible QCD critical point. Some promising advances with non-standard approaches are reviewed.

Plutonium contamination at Maralinga - dosimetry and clean-up criteria

International Nuclear Information System (INIS)

Cooper, M.B.; Martin, L.J.; O'Brien, R.S.; Williams, G.A.

1998-01-01

An area of South Australia remained contaminated following British nuclear weapons tests at Maralinga during 1955 - 1963. Of importance is the long-lived 239-Pu of which some 24 kg was explosively dispersed in several 'minor trials'. The extent, quantities and physical characteristics of the plutonium have been assessed and estimates of dose, dominated by the inhalation pathway in the critical group of Aborigines living a semi-traditional lifestyle, have been made for potential occupants. Rehabilitation of the most contaminated areas is underway, involving scraping of surface soil and burial at depth on site. Dosimetry, together with social and economic factors, underpins the setting of clean-up criteria in terms of activity concentrations averaged over large areas and permissible concentrations of contaminated particles. The possibility of intentional behaviour such as fragment scavenging has also influenced limits on particulate contamination.The standard for this intervention is that the annual committed dose, for any scenario involving permanent occupancy by semi-traditional Aborigines, will be less than 5 mSv. In fact, following the clean-up, annual doses are not expected to exceed 1 mSv for all realistic scenarios. The possibility of intentional behaviour, such as fragment scavenging, has led to limits on particulate contamination. Three plutonium-contaminated sites have been treated by soil-removal. At Taranaki, the most contaminated site, by limiting the activity of the remaining soil to below about 400 kBq/m2 of 239Pu, and by limiting occupancy factors to those typical of hunting activities in a particular location (0.8%), the dose criteria will be met. An area of about 1.5 km 2 has been treated by removal of surface soil at Taranaki. At the other two sites, with no occupancy constraints, more stringent soil-removal criteria have been applied

Ceiling personalized ventilation combined with desk fans for reduced direct and indirect cross-contamination and efficient use of office space

International Nuclear Information System (INIS)

Habchi, Carine; Ghali, Kamel; Ghaddar, Nesreen; Chakroun, Walid; Alotaibi, Sorour

2016-01-01

Highlights: • Cross-infection occurs by direct inhalation and contact of contaminated surfaces. • Mixing ventilation performance is degraded at reduced distance between occupants. • Ceiling personalized ventilation reduces significantly cross-contamination. • The optimized system induces large energy savings compared to mixing ventilation. • The optimized system improves the occupation density from 12 to 8 m 2 per occupant. - Abstract: Crowded offices with short distances separating workers’ stations increase the probability of respiratory cross-infection via two different paths. One path is the contaminant transmission through air by direct inhalation and the other is through the body contact of contaminated surfaces and walls. Mixed ventilation principles used today reduces the probability of cross contamination by increasing the distance between the stations challenging the efficient use of the space or by supplying more fresh air in the space which is energy inefficient. In this work, new cooling and ventilation configuration is studied by modeling using computational fluid dynamics with consideration of space occupancy density while providing good indoor air quality. The configuration considers a ceiling personalized ventilation system equipped with desk fans. The ability of the computational fluid dynamics model in computing the thermal, velocity and concentration fields was validated by experiments and published data. The main objective of the performed experiments was to ensure that the developed computational fluid dynamics model can capture the effect of the desk fan flow rate on particle behavior. The studied system is found to provide acceptable indoor air quality at shorter distance between the occupants compared to the mixing system at considerable energy savings. By optimizing the design of the proposed personalized ventilation system, the occupancy density in an office is enhanced to 8 m 2 per occupant compared to 12 m 2 per occupant for

Inverse modeling of the biodegradation of emerging organic contaminants in the soil-plant system

DEFF Research Database (Denmark)

Hurtado, Carlos; Trapp, Stefan; Bayona, Josep M.

2016-01-01

Understanding the processes involved in the uptake and accumulation of organic contaminants into plants is very important to assess the possible human risk associated with. Biodegradation of emerging contaminants in plants has been observed, but kinetical studies are rare. In this study, we analyse...... experimental data on the uptake of emerging organic contaminants into lettuce derived in a greenhouse experiment. Measured soil, root and leaf concentrations from four contaminants were selected within the applicability domain of a steady-state two-compartment standard plant uptake model: bisphenol A (BPA......), carbamazepine (CBZ), triclosan (TCS) and caffeine (CAF). The model overestimated concentrations in most cases, when no degradation rates in plants were entered. Subsequently, biodegradation rates were fitted so that the measured concentrations were met.Obtained degradation kinetics are in the order, BPA

FINDING STANDARD DEVIATION OF A FUZZY NUMBER

OpenAIRE

Fokrul Alom Mazarbhuiya

2017-01-01

Two probability laws can be root of a possibility law. Considering two probability densities over two disjoint ranges, we can define the fuzzy standard deviation of a fuzzy variable with the help of the standard deviation two random variables in two disjoint spaces.

Preliminary Study Contamination of Organochlorine Pesticide (Heptachlor) and Heavy Metal (Arsenic) in Shallow Groundwater Aquifer of Semarang Coastal Areas

Science.gov (United States)

Rochaddi, Baskoro; Adhi Suryono, Chrisna; Atmodjo, Warsito; Satriadi, Alfi

2018-02-01

The present study was conducted to assess the level of pesticide and heavy metal contamination in shallow aquifer of Semarang coastal areas. Results indicated that Heptachlor and Arsenic were detected in the water samples in the range 0.023-0.055 μg L-1 and 0,03-1,63 μg L-1, respectively. Compared to the standard limits of the organochlorine contents in the water sample by World Health Organization (WHO) limits and Indonesian Drinking and Domestic Water Quality Standard for Ground Water (IWQS), groundwater of Semarang Coastal Areas was contaminated with pesticide and heavy metal. This study has proven the presence of organochlorine and heavy metal contamination of some shallow aquifer supplies in the coastal areas of Semarang.

Best Practices to Limit Contamination of Donor Milk in a Milk Bank.

Science.gov (United States)

Froh, Elizabeth B; Vanderpool, Jill; Spatz, Diane L

2018-01-02

Human milk donated to a milk bank can become contaminated in a number of ways, but processes exist to eradicate pathogenic bacterial growth. Donor human milk may be cultured before or after pasteurization or both. The purpose of this article is to describe standard operations of the Mothers' Milk Bank of the Children's Hospital of Philadelphia, best practices to limit the bacterial contamination of donor human milk, and implications for future research. Copyright © 2018 AWHONN, the Association of Women’s Health, Obstetric and Neonatal Nurses. Published by Elsevier Inc. All rights reserved.

Relic abundance of WIMPs in non-standard cosmological scenarios

Energy Technology Data Exchange (ETDEWEB)

Yimingniyazi, W.

2007-08-06

In this thesis we study the relic density n{sub {chi}} of non--relativistic long--lived or stable particles {chi} in various non--standard cosmological scenarios. First, we discuss the relic density in the non--standard cosmological scenario in which the temperature is too low for the particles {chi} to achieve full chemical equilibrium. We also investigated the case where {chi} particles are non--thermally produced from the decay of heavier particles in addition to the usual thermal production. In low temperature scenario, we calculate the relic abundance starting from arbitrary initial temperatures T{sub 0} of the radiation--dominated epoch and derive approximate solutions for the temperature dependence of the relic density which can accurately reproduces numerical results when full thermal equilibrium is not achieved. If full equilibrium is reached, our ansatz no longer reproduces the correct temperature dependence of the {chi} number density. However, we can contrive a semi-analytic formula which gives the correct final relic density, to an accuracy of about 3% or better, for all cross sections and initial temperatures. We also derive the lower bound on the initial temperature T{sub 0}, assuming that the relic particle accounts for the dark matter energy density in the universe. The observed cold dark matter abundance constrains the initial temperature T{sub 0} {>=}m{sub {chi}}/23, where m{sub {chi}} is the mass of {chi}. Second, we discuss the {chi} density in the scenario where the the Hubble parameter is modified. Even in this case, an approximate formula similar to the standard one is found to be capable of predicting the final relic abundance correctly. Choosing the {chi} annihilation cross section such that the observed cold dark matter abundance is reproduced in standard cosmology, we constrain possible modifications of the expansion rate at T {proportional_to}m{sub {chi}}/20, well before Big Bang Nucleosynthesis. (orig.)

Relic abundance of WIMPs in non-standard cosmological scenarios

International Nuclear Information System (INIS)

Yimingniyazi, W.

2007-01-01

In this thesis we study the relic density n χ of non--relativistic long--lived or stable particles χ in various non--standard cosmological scenarios. First, we discuss the relic density in the non--standard cosmological scenario in which the temperature is too low for the particles χ to achieve full chemical equilibrium. We also investigated the case where χ particles are non--thermally produced from the decay of heavier particles in addition to the usual thermal production. In low temperature scenario, we calculate the relic abundance starting from arbitrary initial temperatures T 0 of the radiation--dominated epoch and derive approximate solutions for the temperature dependence of the relic density which can accurately reproduces numerical results when full thermal equilibrium is not achieved. If full equilibrium is reached, our ansatz no longer reproduces the correct temperature dependence of the χ number density. However, we can contrive a semi-analytic formula which gives the correct final relic density, to an accuracy of about 3% or better, for all cross sections and initial temperatures. We also derive the lower bound on the initial temperature T 0 , assuming that the relic particle accounts for the dark matter energy density in the universe. The observed cold dark matter abundance constrains the initial temperature T 0 ≥m χ /23, where m χ is the mass of χ. Second, we discuss the χ density in the scenario where the the Hubble parameter is modified. Even in this case, an approximate formula similar to the standard one is found to be capable of predicting the final relic abundance correctly. Choosing the χ annihilation cross section such that the observed cold dark matter abundance is reproduced in standard cosmology, we constrain possible modifications of the expansion rate at T ∝m χ /20, well before Big Bang Nucleosynthesis. (orig.)

Propellant Improvement Program. Volume 2. Iron Contamination Effect in HDA (High Density Acid)

Science.gov (United States)

Density Acid ( HDA ) and the effect of iron impurity level up to 100 parts per million as Fe2O3 on HDA heat transfer. Thirty tests were conducted using...resistance heated, circular, 6061T6 aluminum tubes. Results showed that normal nucleate boiling did not occur with either of the HDA compositions. The

Baseline risk assessment of ground water contamination at the uranium mill tailings site near Durango, Colorado

International Nuclear Information System (INIS)

1995-02-01

This risk assessment evaluates the possibility of health and environmental risks from contaminated ground water at the uranium mill tailings site near Durango, Colorado. The former uranium processing site's contaminated soil and material were removed and placed at a disposal site located in Body Canyon, Colorado, during 1986--1991 by the US Departments of Energy's Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating the nature and extent of ground water contamination at the site. This risk assessment follows an approach similar to that used by the US Environmental Protection Agency. The first step is to determine what site-related contaminants are found in ground water samples. The next step in the risk assessment is to determine how much of these contaminants people might ingest if they got their drinking water from a well on the site. In accordance with standard practice for this type of risk assessment, the highest contaminant concentrations from the most contaminated wells are used. The risk assessment then explains the possible health problems that could result from this amount of contamination

Baseline risk assessment of ground water contamination at the uranium mill tailings site near Durango, Colorado

Energy Technology Data Exchange (ETDEWEB)

1995-02-01

This risk assessment evaluates the possibility of health and environmental risks from contaminated ground water at the uranium mill tailings site near Durango, Colorado. The former uranium processing site`s contaminated soil and material were removed and placed at a disposal site located in Body Canyon, Colorado, during 1986--1991 by the US Departments of Energy`s Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating the nature and extent of ground water contamination at the site. This risk assessment follows an approach similar to that used by the US Environmental Protection Agency. The first step is to determine what site-related contaminants are found in ground water samples. The next step in the risk assessment is to determine how much of these contaminants people might ingest if they got their drinking water from a well on the site. In accordance with standard practice for this type of risk assessment, the highest contaminant concentrations from the most contaminated wells are used. The risk assessment then explains the possible health problems that could result from this amount of contamination.

Evaluation of the RSG-GAS Alpha-Beta Aerosol Contaminant Monitor Performance Under Reactor Operation Condition

International Nuclear Information System (INIS)

Hartoyo, Unggul; Setiawanto, Anto; Sumarno, Yulius

2000-01-01

Analysis to evaluate the RSG-GAS alpha-beta aerosol contaminant monitor performance was done. The high potential radiation working area such as in RSG-GAS is important to monitored for personal safety. Further it is necessary to assure that the system monitor is reliable enough under normal conditions as well as emergency condition. The method uses in this analysis are monitoring and comparing with the standard source. The standard course indicator and panel in main control room indicate that the result is 1 x 110 exp 9 Ci/m exp 3. Based on data monitor observation, the RSG-GAS alpha-beta aerosol contaminant monitor system under reactor operation condition has a good enough performance

Recommended reference materials for realization of physicochemical properties density

CERN Document Server

Herington, E F G

1976-01-01

This book first presents the nomenclature and units used in the determination of densities of liquids and solids, followed by a general description of the apparatus and the methods used in the measurement of density, with particular reference to the pycnometric, hydrostatic weighing, magnetic float, and temperature flotation methods. The use of water as a density reference material is then explained, focusing on the isotopic composition of Standard Mean Ocean Water (SMOW) and the absolute density of SMOW as a function of temperature. Problems due to the effect of pressure and dissolved gases o

Pyrolytic Treatment and Fertility Enhancement of Soils Contaminated with Heavy Hydrocarbons.

Science.gov (United States)

Vidonish, Julia E; Zygourakis, Kyriacos; Masiello, Caroline A; Gao, Xiaodong; Mathieu, Jacques; Alvarez, Pedro J J

2016-03-01

Pyrolysis of contaminated soils at 420 °C converted recalcitrant heavy hydrocarbons into "char" (a carbonaceous material similar to petroleum coke) and enhanced soil fertility. Pyrolytic treatment reduced total petroleum hydrocarbons (TPH) to below regulatory standards (typically hydrocarbons (PAHs) was not observed, with post-pyrolysis levels well below applicable standards. Plant growth studies showed a higher biomass production of Arabidopsis thaliana and Lactuca sativa (Simpson black-seeded lettuce) (80-900% heavier) in pyrolyzed soils than in contaminated or incinerated soils. Elemental analysis showed that pyrolyzed soils contained more carbon than incinerated soils (1.4-3.2% versus 0.3-0.4%). The stark color differences between pyrolyzed and incinerated soils suggest that the carbonaceous material produced via pyrolysis was dispersed in the form of a layer coating the soil particles. Overall, these results suggest that soil pyrolysis could be a viable thermal treatment to quickly remediate soils impacted by weathered oil while improving soil fertility, potentially enhancing revegetation.

Assessment of potential impacts of major groundwater contaminants to fall chinook salmon (Oncorhynchus tshawytscha) in the Hanford Reach, Columbia River

International Nuclear Information System (INIS)

Geist, D.R.; Poston, T.M.; Dauble, D.D.

1994-10-01

Past operations of Hanford Site facilities have contaminated the groundwater adjacent to the Hanford Reach of the Columbia River, Washington, with various chemical and radiological constituents. The groundwater is hydraulically connected to the river and contains concentrations of contaminants that sometimes exceed federal and/or state drinking water standards or standards for the protection of aquatic life. For example, concentrations of chromium in shoreline seeps and springs at most 100 Area operable units exceed concentrations found to be toxic to fish. Nitrate and tritium concentrations in shoreline seeps are generally below drinking water standards and concentrations potentially toxic to aquatic life, but nitrate concentrations may be high enough to synergistically interact with and exacerbate chromium toxicity. The Hanford Reach also supports the largest run of fall chinook salmon (Oncorhynchus tshawytscha) in the Columbia River Basin. Numbers of fall chinook salmon returning to the Hanford Reach have increased relative to other mainstem populations during the last 30 years. Groundwater discharge appears to occur near some salmon spawning areas, but contaminants are generally not detectable in surface water samples. The concentration and potential toxicity of contaminants in the interstitial waters of the substrate where fall chinook salmon embryogenesis occurs are presently unknown. New tools are required to characterize the extent of groundwater contaminant discharge to the Hanford Reach and to resolve uncertainties associated with assessment of potential impacts to fall chinook salmon

Microstructure and critical current density in high-Tc metal oxide superconductors

International Nuclear Information System (INIS)

Johnson, S.M.; Gusman, M.I.

1992-03-01

Superconductor powders in the U-Ba-Cu-O (YBCO) and Bi-Pb-Sr-Ca-Cu-O (BSCCO) systems were synthesized by freeze-drying. Powders were characterized, and processed into samples for evaluation of superconducting behavior. Freeze-drying is attractive because the powders have high purity, are homogeneous, have a small size and are active. YBCO powders can be sintered to high density at 890 degrees C. Many compositions, processing approaches and heat treatments were explored in an effort to understand relations between microstructure and critical density, and to improve the critical current density. Powders were also formed into sputtering targets for coating preparation at Stanford University. The highest critical current density achieved with the YBCO powders was ∼15,000 A/cm 2 at 4.2K and 0.5T using powders treated to prevent carbon contamination. The BSCCO materials with the highest critical current density, ∼30,000 A/cm 2 at the same conditions were formed by heat treating melted and quenched samples. All critical current density measurements were made by Stanford University, a subcontractor to this effort. Stanford University also prepared coatings by off-axis magnetron sputtering

Feasibility study to combine the evaluation of radiological and chemical-toxicological effects of old contaminated sites

International Nuclear Information System (INIS)

Jacob, P.; Proehl, G.

1997-01-01

The uranium mining regions of the German Federal States Saxony, Thuringia and Saxony-Anhalt are contaminated by radionuclides and by chemical substances. For both, ionizing radiations and chemicals, concepts and models exists to assess possible health effects for the population living in such areas. However, these assessment models were developed independently for both kinds of contaminants. Therefore, the 9 th Conference of the State Ministers for Environmental Protection have claimed that for the evaluation of contaminated sites the radiological and chemical contaminants should be integrated into a joint assessment. This feasibility study describes the state of the art of the concepts and models used for the evaluation of radiological and chemical contaminants. The similarities and differences of these evaluation methods are identified and discussed. Suggestions are made for an integrated assessment to standardize the evaluation of sites contaminated by radionuclides or chemicals. (orig.) [de

Contamination vs. Exposure

Science.gov (United States)

... into the environment can cause air, water, surfaces, soil, plants, buildings, people, or animals to become contaminated. ... water to remove contamination. This process is called decontamination. Try to avoid spreading contamination to parts of ...

Uses of ANSI/HPS N13.12-1999, "Surface and Volume Radioactivity Standards for Clearance" and Comparison with Existing Standards

Energy Technology Data Exchange (ETDEWEB)

Stansbury, Paul S.; Strom, Daniel J.

2001-04-30

In August of 1999, the American National Standards Institute (ANSI) approved a standard for clearance of materials contaminated with residual levels of radioactivity. "Clearance," as used in the standard, means the movement of material from the control of a regulatory agency to a use or disposition that has no further regulatory controls of any kind. The standard gives derived screening levels (DSLs) in Bq/g and Bq/cm2 for 50 radionuclides. Items or materials with residual surface and volume radioactivity levels below the DSLs can be cleared, that is, managed without regard to their residual radioactivity. Since federal agencies are to use voluntary, industry standards developed by the private sector whenever possible, the standard should play an important role in DOE's regulatory process. The thrust of this report is to explain the standard, make simple observations on its usefulness to DOE, and to explore uses of the standard within DOE facilities beyond the clearance of radioactive materials.

Working group 1A - basis for the standard-safety

International Nuclear Information System (INIS)

Whipple, C.

1993-01-01

This paper presents a summary of the progress made by working group 1A (Basis for the Safety Standard) during the Electric Power Research Institute's EPRI Workshop on the technical basis of EPA HLW Disposal Criteria, March 1993. This group discussed the semantics of terms within the standard 40 CFR Part 191, the implementation of this standard, the advanced notice of rulemaking, the issue of emitting carbon-14 through a gaseous pathway, the strategy of dealing with standards for contamination of drinking water and groundwater, the 100,000 year time frame, and the analysis of specific comments. The specific comments dealt with the cost effectiveness of the standard, the dose histogram for populations and individuals, groundwater definition and the underlying technology driver for this standard

Determination of mycroplasmic contamination by radiometric method

International Nuclear Information System (INIS)

Khashimova, Z.S.

2004-01-01

Full text: Some species of mycoplasmas are pathogenic for man, animals and plants. The problem of mycoplasmic contamination of cultivated cells used in biotechnology for producing of monoclonal antibodies and vaccines is very actual. The plasmatic membrane of mycoplasmas, which does not differ on its structural organization from a membrane of eucariotic cells, takes part in formation of strong surface antigens. Taking into account this fact, it has been investigated mycoplasmic contamination of several kinds of cotton seeds, myelome cells XAg8.653, and hybridoma cells producing monoclonal antibodies to cotton membrane proteins. Mycoplasmic contamination was determined by hybridization of DNA of investigated objects with recombinant plasmids containing mycoplasmas DNA fragments. DNA was isolated from 5 kinds of cotton seedling, cellular cultures and hybridomas according to standard protocols. DNA was denaturated, neutralized and a reaction mix was transferred to nitrocellulose filter. Than filters were hybridizated with universal plasmid sounds namely pMg16 and pAl32, which contained the mycoplasma genomic fragment. These sounds were constructed in the Institute of Cytology of Russian Academy of Science by Borhsenius S.N. at al. [1] and kindly given us for our work. pMg16 and pAl32 were preliminary marked by 32 P - ATP (nick - translation). Hybridization was carried out within night. Filters were washed and placed for radioautography at - 70 o C for 24h. Sensitivity of 32 P - labeled probes in reaction was 1ng of mycoplasmas DNA. It was shown, that only one kind of cotton seeds was not contaminated by mycoplasmas, and hybridoma and myeloma cells was not contaminated. Thus, the presence of mycoplasmas in different objects may be determined using DNA hybridization. This work was supported by the Center of Science and Technology RU (4F No 419)

Nuclear contamination of water resources

International Nuclear Information System (INIS)

1990-01-01

In the wake of the Chernobyl accident, the vulnerability of the water cycle to radionuclide contamination has been an issue of great concern. The impact of the event throughout Europe has been highly variable and wide-ranging, and has demonstrated the need to evaluate the potential risk to drinking water supplies, soilwater and the food chain. This book provides information on radiological standards as they exist at present, on the methods of monitoring, and on concepts in design to minimize risk and to highlight the possible consequences of a nuclear event. With contributions from engineers and scientists from eight countries, this book is a unique source of information about present radiological standards and monitoring requirements. It also includes comprehensive coverage of the effects on water resources of, and deals with the development of management strategies designed to cope with, a nuclear event. There are 19 papers all indexed separately. These are divided into sections -introduction, present radiological standards relating to drinking water, radiological monitoring requirements, the consequences of a nuclear event on water resources and water resource management strategy. The discussion at the end of each section is recorded. (author)

Radioactive contamination level of vehicles resulted from transporting fine rare-earth minerals by rail

International Nuclear Information System (INIS)

Han Kaichun; Yu Boyong; Gao Shengwei

1997-01-01

This paper presents monitoring results of radioactive contamination level of steel open wagon surface resulted from transporting fine rare-earth minerals. Under promising transport conditions (the packaging consists of two layers of plastic bags and two layers of plastic net sacks, each package contains 50 kg of minerals, each vehicle carries 60 t), the surface radioactivity (total α and total β) of 16 vehicles on two lines from Baotou to Wujiachuan (924 km) and from Baotou to Sankeshu (2236 km) was measured before loading, after unloading and washing, using α and β surface contamination detector. The results showed that the radioactive contamination level of the vehicle surface after unloading appeared significantly different. The contamination level of vehicle bases was higher than that of both sides, long distance vehicles was higher than that of short distance vehicles. The radioactive contamination level of vehicles surface after washing was below the standard limits, these vehicles can be used for ordinary goods transport

Assessing and minimizing contamination in time of flight based validation data

Science.gov (United States)

Lennox, Kristin P.; Rosenfield, Paul; Blair, Brenton; Kaplan, Alan; Ruz, Jaime; Glenn, Andrew; Wurtz, Ronald

2017-10-01

Time of flight experiments are the gold standard method for generating labeled training and testing data for the neutron/gamma pulse shape discrimination problem. As the popularity of supervised classification methods increases in this field, there will also be increasing reliance on time of flight data for algorithm development and evaluation. However, time of flight experiments are subject to various sources of contamination that lead to neutron and gamma pulses being mislabeled. Such labeling errors have a detrimental effect on classification algorithm training and testing, and should therefore be minimized. This paper presents a method for identifying minimally contaminated data sets from time of flight experiments and estimating the residual contamination rate. This method leverages statistical models describing neutron and gamma travel time distributions and is easily implemented using existing statistical software. The method produces a set of optimal intervals that balance the trade-off between interval size and nuisance particle contamination, and its use is demonstrated on a time of flight data set for Cf-252. The particular properties of the optimal intervals for the demonstration data are explored in detail.

Treatment of plutonium contaminations

International Nuclear Information System (INIS)

Lafuma, J.

1983-01-01

Three kinds of plutonium contaminations were considered: skin contamination; contaminated wounds; contamination by inhalation. The treatment of these contaminations was studied for insoluble (oxide and metal forms) and soluble plutonium (complexes). The use of DTPA and therapeutic problems encountered with stable plutonium complexes were analyzed. The new possibilities of internal decontamination using Puchel and LICAM were evaluated [fr

Contaminants in Liquid Organic Fertilizers Used for Agriculture in Japan.

Science.gov (United States)

Hai, Dao M; Qiu, Xuchun; Xu, Hai; Honda, Masato; Yabe, Mitsuyasu; Kadokami, Kiwao; Shimasaki, Yohei; Oshima, Yuji

2017-07-01

To provide an overview of anthropogenic contaminants in liquid organic fertilizers (LOFs), products from four biogas plants in Kyushu, Japan, were analyzed for a wide range of contaminants, including copper, cadmium, tributyltin (TBT), dibutyltin (DBT), perfluorooctane sulfonate, 952 semi-volatile organic compounds, and 89 antibiotics. The highest concentrations of copper (31.1 mg/L) and cadmium (0.08 mg/L) were found in LOFs from the Hita biogas plant. Only ofloxacin and sulfapyridine were detected in total 89 antibiotics screened. TBT, DBT, and perfluorooctane sulfonate were present at low concentrations in the LOFs from all four locations. Among the 952 semi-volatile organic compounds, 78 compounds were detected in at least one sample and were present at concentrations between 1.2 and 139.6 mg/L. On the basis of comparisons with previous studies and quality standards for the use of organic fertilizers, the concentrations of contaminants in the studied LOFs indicate that they might be safe for agricultural purposes.

A Non-Structural Investigation of VIX Risk Neutral Density

DEFF Research Database (Denmark)

Barletta, Andrea; Santucci de Magistris, Paolo; Violante, Francesco

We propose a non-structural pricing method to derive the risk-neutral density (RND) implied by options on the CBOE Volatility Index (VIX). The methodology is based on orthogonal polynomial expansions around a kernel density and yields the RND of the underlying asset without the need for a paramet......We propose a non-structural pricing method to derive the risk-neutral density (RND) implied by options on the CBOE Volatility Index (VIX). The methodology is based on orthogonal polynomial expansions around a kernel density and yields the RND of the underlying asset without the need...... for a parametric specification. The classic family of Laguerre expansions is extended to include the GIG and the generalized Weibull kernels, thus relaxing the conditions required on the tail decay rate of the RND to ensure convergence. We show that the proposed methodology yields an accurate approximation...... of the RND in a large variety of cases, also when the no-arbitrage and efficient option prices are contaminated by measurement errors. Our empirical investigation, based on a panel of traded VIX options, reveals some stylized facts on the RND of VIX. We find that a common stochastic factor drives the dynamic...

Reactive dispersive contaminant transport in coastal aquifers: Numerical simulation of a reactive Henry problem

KAUST Repository

Nick, H.M.

2013-02-01

The reactive mixing between seawater and terrestrial water in coastal aquifers influences the water quality of submarine groundwater discharge. While these waters come into contact at the seawater groundwater interface by density driven flow, their chemical components dilute and react through dispersion. A larger interface and wider mixing zone may provide favorable conditions for the natural attenuation of contaminant plumes. It has been claimed that the extent of this mixing is controlled by both, porous media properties and flow conditions. In this study, the interplay between dispersion and reactive processes in coastal aquifers is investigated by means of numerical experiments. Particularly, the impact of dispersion coefficients, the velocity field induced by density driven flow and chemical component reactivities on reactive transport in such aquifers is studied. To do this, a hybrid finite-element finite-volume method and a reactive simulator are coupled, and model accuracy and applicability are assessed. A simple redox reaction is considered to describe the degradation of a contaminant which requires mixing of the contaminated groundwater and the seawater containing the terminal electron acceptor. The resulting degradation is observed for different scenarios considering different magnitudes of dispersion and chemical reactivity. Three reactive transport regimes are found: reaction controlled, reaction-dispersion controlled and dispersion controlled. Computational results suggest that the chemical components\\' reactivity as well as dispersion coefficients play a significant role on controlling reactive mixing zones and extent of contaminant removal in coastal aquifers. Further, our results confirm that the dilution index is a better alternative to the second central spatial moment of a plume to describe the mixing of reactive solutes in coastal aquifers. © 2012 Elsevier B.V.

Control of bacterial contamination of washbasin taps and output water using Ecasol: a one-year study.

LENUS (Irish Health Repository)

Boyle, M A

2012-04-01

Contaminated washbasin taps and output water are an important source of bacteria that may cause nosocomial infection. A five-week pretreatment study of hot and cold water from 15 washbasin taps at Dublin Dental Hospital showed consistently heavy contamination by aerobic heterotrophic bacteria: mean bacterial counts of 482.5 [standard deviation (SD) 293] colony-forming units (cfu)\\/mL and 5022 (SD 4322) cfu\\/mL, respectively.

Postmortem validation of breast density using dual-energy mammography

OpenAIRE

Molloi, Sabee; Ducote, Justin L.; Ding, Huanjun; Feig, Stephen A.

2014-01-01

Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dua...

Adverse events associated with metal contamination of traditional chinese medicines in Korea: a clinical review.

Science.gov (United States)

Kim, Hyunah; Hughes, Peter J; Hawes, Emily M

2014-09-01

This study was performed to review studies carried out in Korea reporting toxic reactions to traditional Chinese medicines (TCMs) as a result of heavy metal contamination. PubMed (1966-August 2013) and International Pharmaceutical Abstracts (1965-August 2013) were searched using the medical subject heading terms of "Medicine, Chinese Traditional," "Medicine, Korean Traditional," "Medicine, Traditional," "Metals, Heavy," and "Drug Contamination". For Korean literature, Korea Med (http://www.koreamed.org), the Korean Medical Database (http://kmbase.medric.or.kr), National Discovery for Science Leaders (www.ndsl.kr), Research Information Sharing Service (http://www.riss.kr), and Google Scholar were searched using the terms "Chinese medicine," "Korean medicine," "herbal medicine," and "metallic contamination" in Korean. Bibliographies of case reports and case series, identified using secondary resources, were also utilized. Only literature describing cases or studies performed in Korea were included. Case reports identified clear issues with heavy metal, particularly lead, contamination of TCMs utilized in Korea. No international standardization guidelines for processing, manufacturing and marketing of herbal products exist. Unacceptably high levels of toxic metals can be present in TCM preparations. Health care providers and patients should be educated on the potential risks associated with TCMs. International advocacy for stricter standardization procedures for production of TCMs is warranted.

The effect of water contamination on the dew-point temperature scale realization with humidity generators

Science.gov (United States)

Vilbaste, M.; Heinonen, M.; Saks, O.; Leito, I.

2013-08-01

The purpose of this paper is to study the effect of contaminated water in the context of humidity generators. Investigation of different methods to determine the drop in dew-point temperature due to contamination and experiments on actual contamination rates are reported. Different methods for calculating the dew-point temperature effect from electrical conductivity and density measurements are studied with high-purity water and aqueous solutions of NaCl and LiCl. The outcomes of the calculation methods are compared with the results of direct humidity measurements. The results show that the often applied Raoult's law based calculation method is in good agreement with other methods. For studying actual contamination, water samples were kept in glass, plastic, copper and stainless-steel vessels for up to 13 months to investigate natural ionic and organic contamination in vessels with different wall materials. The amount of ionic contamination was found to be higher in copper and glass vessels than in stainless-steel and plastic vessels. The amount of organic contamination was found to be highest in the plastic vessel. In all the cases, however, the corresponding drop in dew-point temperature due to natural contamination was found to be below 0.1 mK. The largest rate of change of dew-point temperature was 26 µK/month. Thus, if proper cleanness is maintained in a humidity generator the effect of contamination of water in the saturator is insignificant compared with the major uncertainty components even in the most accurate generators today.

Frozen Soil Barrier. Subsurface Contaminants Focus Area. OST Reference No. 51

International Nuclear Information System (INIS)

1999-01-01

Problem: Hazardous and radioactive materials have historically been disposed of at the surface during operations at Department of Energy facilities. These contaminants have entered the subsurface, contaminating soils and groundwater resources. Remediation of these groundwater plumes using the baseline technology of pump and treat is expensive and takes a long time to complete. Containment of these groundwater plumes can be alternative or an addition to the remediation activities. Standard containment technologies include slurry walls, sheet piling, and grouting. These are permanent structures that once installed are difficult to remove. How It Works: Frozen Soil Barrier technology provides a containment alternative, with the key difference being that the barrier can be easily removed after a period of time, such as after the remediation or removal of the source is completed. Frozen Soil Barrier technology can be used to isolate and control the migration of underground radioactive or other hazardous contaminants subject to transport by groundwater flow. Frozen Soil Barrier technology consists of a series of subsurface heat transfer devices, known as thermoprobes, which are installed around a contaminant source and function to freeze the soil pore water. The barrier can easily be maintained in place until remediation or removal of the contaminants is complete, at which time the barrier is allowed to thaw.

A spectrum standardization approach for laser-induced breakdown spectroscopy measurements

Energy Technology Data Exchange (ETDEWEB)

Wang Zhe, E-mail: zhewang@mail.tsinghua.edu.cn; Li Lizhi; West, Logan; Li Zheng, E-mail: lz-dte@tsinghua.edu.cn; Ni Weidou

2012-02-15

This paper follows and completes a previous presentation of a spectrum normalization method for laser-induced breakdown spectroscopy (LIBS) measurements by converting the experimentally recorded line intensity at varying operational conditions to the intensity that would be obtained under a 'standard state' condition, characterized by a standard plasma temperature, electron number density, and total number density of the interested species. At first, for each laser shot and corresponding spectrum, the line intensities of the interested species are converted to the intensity at a fixed plasma temperature and electron number density, but with varying total number density. Under this state, if the influence of changing plasma morphology is neglected, the sum of multiple spectral line intensities for the measured element is proportional to the total number density of the specific element. Therefore, the fluctuation of the total number density, or the variation of ablation mass, can be compensated for by applying the proportional relationship. The application of this method to Cu in 29 brass alloy samples, showed an improvement over the commonly applied normalization method with regard to measurement precision and accuracy. The average relative standard deviation (RSD) value, average value of the error bar, R{sup 2}, root mean square error of prediction (RMSEP), and average value of the maximum relative error were: 5.29%, 0.68%, 0.98, 2.72%, 16.97%, respectively, while the above parameter values for normalization with the whole spectrum area were: 8.61%, 1.37%, 0.95, 3.28%, 29.19%, respectively. - Highlights: Black-Right-Pointing-Pointer Intensity converted into an ideal standard plasma state for uncertainty reduction. Black-Right-Pointing-Pointer Ablated mass fluctuations compensated by variation of sum of multiple intensities. Black-Right-Pointing-Pointer A spectrum standardization model established. Black-Right-Pointing-Pointer Results in both uncertainty

Prevalence and serotypes of Listeria monocytogenes contamination in Chinese beef processing plants.

Science.gov (United States)

Zhu, Lixian; Feng, Xiaohui; Zhang, Lihua; Zhu, Ruiliang; Luo, Xin

2012-06-01

The aim of this work was to study the epidemiology of Listeria spp., particularly Listeria monocytogenes, and to identify the serotypes present in contaminated samples from beef processing plants in China. A total of 439 samples were obtained from bovine feces, hides, and carcasses at three commercial processing plants. A standard protocol (ISO 11290-1) was followed to detect Listeria spp. and L. monocytogenes, and multiplex polymerase chain reaction was used to identify the various L. monocytogenes serotypes. The overall prevalences of Listeria spp. and L. monocytogenes were 65.6% and 26.4%, respectively, and the contamination was highest in the hide samples. The identified L. monocytogenes serotypes were 1/2c and 1/2a. The results of the current study indicate that Listeria spp. contamination is common in Chinese beef processing plants; specific measures should be taken to prevent and/or treat L. monocytogenes contamination of feces and hides in beef slaughter plants. Furthermore, because Listeria spp. contamination was found to be prevalent, it should, therefore, be studied further. The prevention of cases of sporadic listeriosis in China should also be addressed.

MATERIAL COMPOSITIONS AND NUMBER DENSITIES FOR NEUTRONICS CALCULATIONS

International Nuclear Information System (INIS)

D. A. Thomas

1996-01-01

The purpose of this analysis is to calculate the number densities and isotopic weight percentages of the standard materials to be used in the neutronics (criticality and radiation shielding) evaluations by the Waste Package Development Department. The objective of this analysis is to provide material number density information which can be referenced by future neutronics design analyses, such as for those supporting the Conceptual Design Report

Phytoextraction of Cd-contaminated soil by carambola (Averrhoa carambola) in field trials.

Science.gov (United States)

Li, J T; Liao, B; Dai, Z Y; Zhu, R; Shu, W S

2009-08-01

Use of metal-accumulating woody species to extract metals from heavy metal contaminated soil has received more attention. While considerable studies have focused on the phytoextraction potential of willow (Salix spp.) and poplar (Populus spp.), similar information is rare for other woody species. Carambola (Averrhoa carambola) is a high-biomass tree and has been identified as a new Cd-accumulating species. The present study aimed to evaluate the Cd phytoextraction potential of carambola under field condition. After growing in a slightly Cd-contaminated site for about 170 d, the carambola stand initiated by seed-seedling with high planting density (encoded with "HD-1yr") attained a high shoot biomass yield of 18.6 t ha(-1) and extracted 213 g Cdha(-1), resulting in a 1.6-fold higher Cd removal efficiency than that of a contrasting stand established by grafted-seedling with low planting density (5.3% vs. 2%). That is, "HD-1yr" would remove 50% of the total soil Cd with 13yr, assuming that the Cd removal efficiency would not change over time. Further, one crop of "HD-1yr" significantly decreased (63-69%) the Cd uptake by subsequent vegetables. Among the four carambola stands established using grafted-seedling, the 2-yr-old stand exhibited the highest annual Cd removal efficiency (3.7%), which was yet lower than that of "HD-1yr". These results suggested that phytoextraction of Cd by carambola (especially for "HD-1yr" stand) presented a feasible option to clean up agricultural soils slightly contaminated by Cd.

Contaminant Effects on California Bay–Delta Species and Human Health

Directory of Open Access Journals (Sweden)

Stephanie Fong

2016-12-01

Full Text Available doi: https://doi.org/10.15447/sfews.2016v14iss4art5Many contaminants in the California Bay–Delta (Bay–Delta exceed regulatory standards, affect aquatic species, and potentially affect human health. Recent studies provide multiple lines of evidence that contaminants affect species of concern in the Bay–Delta (e.g., the decline of several important fish species referred to as the “Pelagic Organism Decline” or POD. Contaminants occur as dynamic complex mixtures and exert effects at multiple levels of biological organization. Multiple chemicals impair processes at cellular and physiological levels (measured as growth, development, and behavior abnormalities, and when viability and reproductive output are affected, populations are affected. As an important example, the population decline of the endangered Delta Smelt (Hypomesus transpacificus is significantly associated with multiple stressors, including insecticide use. New analyses presented in this paper show significant correlations between pyrethroid use and declining abundance of POD fish species. Water sampled from the Bay–Delta causes multiple deleterious effects in fish, and Delta Smelt collected from the Bay–Delta exhibit contaminant effects. Fish prey items are also affected by contaminants; this may have an indirect effect on their populations. Co-occurrence with thermal changes or disease can exacerbate contaminant effects. Contaminants also pose threats to human health via consumption of fish and shellfish, drinking water, and contact recreation, in particular, mercury, cyanobacteria toxins, disinfection byproducts, pathogens, pesticides, and pharmaceuticals and personal care products. The role of contaminants in the decline of Bay–Delta species is difficult to accurately assess in a complex, dynamic system. However, tools and approaches are available to evaluate contaminant effects on Bay–Delta species, and separate the effects of multiple stressors. Integrated

Sampling Error in Relation to Cyst Nematode Population Density Estimation in Small Field Plots.

Science.gov (United States)

Župunski, Vesna; Jevtić, Radivoje; Jokić, Vesna Spasić; Župunski, Ljubica; Lalošević, Mirjana; Ćirić, Mihajlo; Ćurčić, Živko

2017-06-01

Cyst nematodes are serious plant-parasitic pests which could cause severe yield losses and extensive damage. Since there is still very little information about error of population density estimation in small field plots, this study contributes to the broad issue of population density assessment. It was shown that there was no significant difference between cyst counts of five or seven bulk samples taken per each 1-m 2 plot, if average cyst count per examined plot exceeds 75 cysts per 100 g of soil. Goodness of fit of data to probability distribution tested with χ 2 test confirmed a negative binomial distribution of cyst counts for 21 out of 23 plots. The recommended measure of sampling precision of 17% expressed through coefficient of variation ( cv ) was achieved if the plots of 1 m 2 contaminated with more than 90 cysts per 100 g of soil were sampled with 10-core bulk samples taken in five repetitions. If plots were contaminated with less than 75 cysts per 100 g of soil, 10-core bulk samples taken in seven repetitions gave cv higher than 23%. This study indicates that more attention should be paid on estimation of sampling error in experimental field plots to ensure more reliable estimation of population density of cyst nematodes.

Device for contaminating laboratory animals by inhalation of radioactive aerosols

International Nuclear Information System (INIS)

Lutz, M.; Rouvroy, H.

1966-01-01

The contamination enclosure is made up of a sphere to which are attached an aerosol generator, containers adapted to the animals to be used, and the atmospheric sampling system. The sphere is placed in a protective glove-box, the latter being itself protected by an introduction chamber fitted with locking access lids. A detailed description is given of the working principle. As an example, some results are given concerning the contamination of rats by a plutonium oxide aerosol: characteristics of the powder (mean diameter 0.50 μ - standard deviation: 1.4), examination and evolution of the atmospheric activity as a function of time, evaluation of the retention by the lungs by means of histological and autoradiographic examinations. (authors) [fr

In-situ protein determination to monitor contamination in a centrifugal partition chromatograph.

Science.gov (United States)

Bouiche, Feriel; Faure, Karine

2017-05-15

Centrifugal partition chromatography (CPC) works with biphasic liquid systems including aqueous two-phase systems. Metallic rotors are able to retain an aqueous stationary phase able to purify proteins. But the adhesion of proteins to solid surface may pose a cross-contamination risk during downstream processes. So it is of utmost importance to ensure the cleanliness of the equipment and detect possible protein contamination in a timely manner. Thereby, a direct method that allows the determination of the effective presence of proteins and the extent of contamination in the metallic CPC rotors was developed. This in-situ method is derived from the Amino Density Estimation by Colorimetric Assay (ADECA) which is based on the affinity of a dye, Coomassie Brillant Blue (CBB), with protonated N + groups of the proteins. In this paper, the ADECA method was developed dynamically, on a 25 mL stainless-steel rotor with various extents of protein contaminations using bovine serum albumin (BSA) as a fouling model. The eluted CBB dye was quantified and found to respond linearly to BSA contamination up to 70 mg injected. Limits of detection and quantification were recorded as 0.9 mg and 3.1 mg, respectively. While the non-specific interactions between the dye and the rotor cannot currently be neglected, this method allows for in situ determination of proteins contamination and should contribute to the development of CPC as a separation tool in protein purification processes. Copyright © 2017 Elsevier Inc. All rights reserved.

Optimized molecular resolution of cross-contamination alerts in clinical mycobacteriology laboratories

Directory of Open Access Journals (Sweden)

de Viedma Darío

2008-02-01

Full Text Available Abstract Background The phenomenon of misdiagnosing tuberculosis (TB by laboratory cross-contamination when culturing Mycobacterium tuberculosis (MTB has been widely reported and it has an obvious clinical, therapeutic and social impact. The final confirmation of a cross-contamination event requires the molecular identification of the same MTB strain cultured from both the potential source of the contamination and from the false-positive candidate. The molecular tool usually applied in this context is IS6110-RFLP which takes a long time to provide an answer, usually longer than is acceptable for microbiologists and clinicians to make decisions. Our purpose in this study is to evaluate a novel PCR-based method, MIRU-VNTR as an alternative to assure a rapid and optimized analysis of cross-contamination alerts. Results MIRU-VNTR was prospectively compared with IS6110-RFLP for clarifying 19 alerts of false positivity from other laboratories. MIRU-VNTR highly correlated with IS6110-RFLP, reduced the response time by 27 days and clarified six alerts unresolved by RFLP. Additionally, MIRU-VNTR revealed complex situations such as contamination events involving polyclonal isolates and a false-positive case due to the simultaneous cross-contamination from two independent sources. Conclusion Unlike standard RFLP-based genotyping, MIRU-VNTR i could help reduce the impact of a false positive diagnosis of TB, ii increased the number of events that could be solved and iii revealed the complexity of some cross-contamination events that could not be dissected by IS6110-RFLP.

New mechanism for generating density perturbations from inflation

International Nuclear Information System (INIS)

Dvali, Gia; Gruzinov, Andrei; Zaldarriaga, Matias

2004-01-01

We propose a new mechanism to generate density perturbations in inflationary models. Spatial fluctuations in the decay rate of the inflaton field to ordinary matter lead to fluctuations in the reheating temperature. We argue that in most realistic models of inflation the coupling of the inflaton to normal matter is determined by the vacuum expectation values of fields in the theory. If those fields are light during inflation (this is a generic situation in the minimal models of supersymmetric inflation) they will fluctuate leading to density perturbations through the proposed mechanism. We show that these fluctuations could easily dominate over the ones generated through the standard mechanism. The new scenario has several consequences for inflation model building and observations. The proposed mechanism allows us to generate the observed level of density perturbations with a much lower scale of inflation and thus generically predicts a smaller level of gravitational waves. The relation between the slope of the spectrum of the produced density perturbations and the potential of the inflaton field is different from the standard relations obtained in the context of slow roll inflation. Because the field responsible for the fluctuations is not the inflaton, it can have significantly larger self-couplings and thus density perturbations could be non-Gaussian. The non-Gaussianity can be large enough to be detectable by CMB and large scale structure observations

Absolute Salinity, ''Density Salinity'' and the Reference-Composition Salinity Scale: present and future use in the seawater standard TEOS-10

Directory of Open Access Journals (Sweden)

D. G. Wright

2011-01-01

Full Text Available Salinity plays a key role in the determination of the thermodynamic properties of seawater and the new TEOS-10¹ standard provides a consistent and effective approach to dealing with relationships between salinity and these thermodynamic properties. However, there are a number of practical issues that arise in the application of TEOS-10, both in terms of accuracy and scope, including its use in the reduction of field data and in numerical models.

First, in the TEOS-10 formulation for IAPSO Standard Seawater, the Gibbs function takes the Reference Salinity as its salinity argument, denoted S_R, which provides a measure of the mass fraction of dissolved material in solution based on the Reference Composition approximation for Standard Seawater. We discuss uncertainties in both the Reference Composition and the Reference-Composition Salinity Scale on which Reference Salinity is reported. The Reference Composition provides a much-needed fixed benchmark but modified reference states will inevitably be required to improve the representation of Standard Seawater for some studies. However, the Reference-Composition Salinity Scale should remain unaltered to provide a stable representation of salinity for use with the TEOS-10 Gibbs function and in climate change detection studies.

Second, when composition anomalies are present in seawater, no single salinity variable can fully represent the influence of dissolved material on the thermodynamic properties of seawater. We consider three distinct representations of salinity that have been used in previous studies and discuss the connections and distinctions between them. One of these variables provides the most accurate representation of density possible as well as improvements over Reference Salinity for the determination of other thermodynamic properties. It is referred to as "Density Salinity" and is represented by the symbol

Statistical density of nuclear excited states

Directory of Open Access Journals (Sweden)

V. M. Kolomietz

2015-10-01

Full Text Available A semi-classical approximation is applied to the calculations of single-particle and statistical level densities in excited nuclei. Landau's conception of quasi-particles with the nucleon effective mass m* < m is used. The approach provides the correct description of the continuum contribution to the level density for realistic finite-depth potentials. It is shown that the continuum states does not affect significantly the thermodynamic calculations for sufficiently small temperatures T ≤ 1 MeV but reduce strongly the results for the excitation energy at high temperatures. By use of standard Woods - Saxon potential and nucleon effective mass m* = 0.7m the A-dependency of the statistical level density parameter K was evaluated in a good qualitative agreement with experimental data.

Public health and regulatory concerns in the event of 131 milk contamination from fallout or a nuclear facility accident

International Nuclear Information System (INIS)

Davies, Sherwood

1978-01-01

Deposition of 131 I on pasture land in high density milk producing areas may result in large volumes of contaminated milk entering the food chain. The potential for radiation exposure of the population through milk may extend to relatively large areas. The magnitude of exposure through ingestion of milk may be 300 to 700 times greater than through inhalation. Measurable amounts of 131 I can be identified in milk within 12-24 hours after a contaminating event with peak milk concentrations occurring within a few days. Implementation of needed protective actions within a day following a contaminating event can minimize milk contamination and avoid unnecessary population exposure. Regulatory agencies should consider the potential for milk contamination, point of control, i.e., dairy farm-milk plant-man, time framework for initiating needed protective actions, effectiveness of control procedures, sampling and laboratory resources, interpretation of anomalous data and preplanned enforcement actions. (author)

German experience in recycling of contaminated scrap by melting

International Nuclear Information System (INIS)

Quade, U.

2003-01-01

Recycling of radioactively contaminated scrap to products for further application in the nuclear cycle is Germany as an economic alternative. It has been shown that recycling within the nuclear industry reduces the collective dose as well as the number of individuals who receive doses. In the future when decommissioning of NPP will increase, a high amount of slightly radioactive steel scrap has to be managed safely. Recycling will play an important role to keep as much of these materials within the nuclear cycle as economically possible. Siempelkamp supplies a broad range of products made of recycled material from the nuclear industry. Containers made of nodular cast iron for transport and storage of radwaste as well as containers made of concrete with iron granules additive to increase the density up to 4 g/cm 3 , are offered. Interim and final disposal volume, having consequences on costs, can be reduced when recycling is applied for slightly contaminated metallic scrap

Antimicrobial Properties of Selected Copper Alloys on Staphylococcus aureus and Escherichia coli in Different Simulations of Environmental Conditions: With vs. without Organic Contamination

Directory of Open Access Journals (Sweden)

Anna Różańska

2017-07-01

Full Text Available Background: Hospital equipment made from copper alloys can play an important role in complementing traditional methods of disinfection. Aims of the study: The aim of this study was to assess the dynamics of the antimicrobial properties of selected copper alloys in different simulations of environmental conditions (with organic contamination vs. without organic contamination, and to test alternatives to the currently used testing methods. Materials and Methods: A modification of Japanese standard JIS Z 2801 as well as Staphylococcus aureus (SA and Escherichia coli (EC suspended in NaCl vs. tryptic soy broth (TSB were used in tests performed on seven commonly used copper alloys, copper, and stainless steel. Results: A much faster reduction of the bacterial suspension was observed for the inoculum prepared in NaCl than in TSB. A faster reduction for EC than for SA was observed in the inoculum prepared in NaCl. The opposite results were found for the inoculum based on TSB. A significant correlation between the copper concentration in the copper alloys and the time and degree of bacterial suspension reduction was only observed in the case of EC. Conclusions: This study confirmed the antimicrobial properties of copper alloys, and additionally showed that Staphylococcus aureus was more resistant than Escherichia coli in the variant of the experiment without organic contamination. However, even for SA, a total reduction of the bacterial inoculum’s density took no longer than 2 h. Under conditions simulating organic contamination, all of the tested alloys were shown to have bactericidal or bacteriostatic properties, which was contrary to the results from stainless steel.

Living in highly dynamic polluted river floodplains, do contaminants contribute to population and community effects?

International Nuclear Information System (INIS)

Klok, Chris; Kraak, Michiel H.S.

2008-01-01

The aim of this paper was to collect evidence for the effects of contaminants on biota in a highly dynamic river Rhine floodplain. To this purpose we reviewed the results of circa 10 studies performed in this floodplain. The floodplain was contaminated with elevated levels of cadmium, copper, PAHs, and PCBs and high levels of zinc which were at some sites above legislative values. The results showed that the present contaminants were accumulated by the floodplain inhabiting organisms, but meanwhile population and community effects were ambiguous. Only for the mayfly Ephoron virgo clear effects were detected at the level of the single floodplain. The absence of clear population and community effects is puzzling since at lower contaminant concentrations adverse effects were detected in other environments. Factors that may mask toxic effects include flooding and food quality and quantity. We conclude that given the site specific conditions, being an open, eutrophic system with a highly dynamic flooding pattern, assessment of the contribution of toxicants to observed population density or biomass and community composition requires 1] an increase in number of replicates; 2] a larger scale of investigation and 3] comparison to stable systems with comparable contamination levels

Documenting the Effectiveness of Cosorption of Airborne Contaminants by a Field-Installed Active Desiccant System: Final Report - Phase 2D

Energy Technology Data Exchange (ETDEWEB)

Fischer, J

2003-01-23

The final report for Phase 1 of this research effort (ORNL/SUB/94-SV004/1) concluded that a significant market opportunity would exist for active desiccant systems if it could be demonstrated that they can remove a significant proportion of common airborne contaminants while simultaneously performing the primary function of dehumidifying a stream of outdoor air or recirculated building air. If the engineering community begins to follow the intent of ASHRAE Standard 62, now part of all major building codes, the outdoor air in many major cities may need to be pre-cleaned before it is introduced into occupied spaces. Common air contaminant cosorption capability would provide a solution to three important aspects of the ASHRAE 62-89 standard that have yet to be effectively addressed by heating, ventilation, and air-conditioning (HVAC) equipment manufacturers: (1) The ASHRAE standard defines acceptable outdoor air quality. If the outdoor air contains unacceptable levels of certain common outdoor air contaminants (e.g., sulfur dioxide, ozone), then the standard requires that these contaminants be removed from the outdoor air stream to reach compliance with the acceptable outdoor air quality guidelines. (2) Some engineers prefer to apply a filtration or prescriptive approach rather than a ventilation approach to solving indoor air quality problems. The ASHRAE standard recognizes this approach provided that the filtration technology exists to remove the gaseous contaminants encountered. The performance of current gaseous filtration technologies is not well documented, and they can be costly to maintain because the life of the filter is limited and the cost is high. Moreover, it is not easy to determine when the filters need changing. In such applications, an additional advantage provided by the active desiccant system would be that the same piece of equipment could control space humidity and provide filtration, even during unoccupied periods, if the active desiccant system

Cleanup of contaminated areas; La bonifica di aree contaminate

Energy Technology Data Exchange (ETDEWEB)

Beone, G; Carbone, A I; Zagaroli, M [ENEA - Dipartimento Protezione Ambientale e Salute dell' Uomo, Centro Ricerche Energia, Casaccia (Italy)

1989-01-15

The paper deals with the problem of contaminated areas cleanup, in order to eliminate every possible damage for man safety and environment and to site recovery for some utilization, The first step of cleanup operation is site characterization, that is followed by a pianificazion activity for a better definition of staff qualification, technology to be used, protection and prevention instruments for the risks due to contaminants handling. The second section describes the different remedial technologies for contaminated sites. Remedial technologies may be divided into on-site/off-site and in-situ treatments, according to whether materials (waste, soil, water) are moved to another location or not, respectively. Finally, it is outlined that contaminated areas cleanup is a typical multidisciplinary activity because very different competences are required. (author)

40 CFR 141.51 - Maximum contaminant level goals for inorganic contaminants.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Maximum contaminant level goals for inorganic contaminants. 141.51 Section 141.51 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Maximum Contaminant Level...

40 CFR 141.50 - Maximum contaminant level goals for organic contaminants.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Maximum contaminant level goals for organic contaminants. 141.50 Section 141.50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Maximum Contaminant Level...

40 CFR 141.52 - Maximum contaminant level goals for microbiological contaminants.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Maximum contaminant level goals for microbiological contaminants. 141.52 Section 141.52 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Maximum Contaminant Level...

Assessment of the environmental radioactive contamination levels by depleted uranium after NATO aggression on FR Yugoslavia

International Nuclear Information System (INIS)

Pavlovic, S.; Pavlovic, R.; Markovic, S; Plecas, I.

2001-01-01

During NATO aggression on FR Yugoslavia various ammunition have been used, some of them for the first time. Among others, 30 mm bullets with depleted uranium (DU) penetrators have been used. Radioactivity contamination surveys have started during the war due to indications that DU is used in cruise missiles. Besides that, there were a lot of radioactivity analysis of food, drinking water etc. Some of the obtained results are presented in this paper. Depleted uranium ammunition can permanently contaminate environment and so produce effects on population. Relation of the international radiation and environmental protection standards and contamination levels are discussed as well. (author)

Contamination analysis unit

International Nuclear Information System (INIS)

Gregg, H.R.; Meltzer, M.P.

1996-01-01

The portable Contamination Analysis Unit (CAU) measures trace quantities of surface contamination in real time. The detector head of the portable contamination analysis unit has an opening with an O-ring seal, one or more vacuum valves and a small mass spectrometer. With the valve closed, the mass spectrometer is evacuated with one or more pumps. The O-ring seal is placed against a surface to be tested and the vacuum valve is opened. Data is collected from the mass spectrometer and a portable computer provides contamination analysis. The CAU can be used to decontaminate and decommission hazardous and radioactive surfaces by measuring residual hazardous surface contamination, such as tritium and trace organics. It provides surface contamination data for research and development applications as well as real-time process control feedback for industrial cleaning operations and can be used to determine the readiness of a surface to accept bonding or coatings. 1 fig

Harvesting contaminants from liquid