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Sample records for radiatively active trace

  1. EVALUATION OF SIGNIFICANT ANTHROPOGENIC SOURCES OF RADIATIVELY IMPORTANT TRACE GASES

    The report is an initial evaluation of significant anthropogenic sources of radiatively important trace gases. missions of greenhouse gases from human activities--including fossil fuel combustion, industrial/agricultural activities, and transportation--contribute to the increasin...

  2. Trace element measurements with synchrotron radiation

    Hanson, A.L.; Kraner, H.W.; Jones, K.W.; Gordon, B.M.; Mills, R.E.

    1982-01-01

    Aspects of the application of synchrotron radiation to trace element determinations by x-ray fluorescence have been investigated using beams from the Cornell facility, CHESS. Fluoresced x rays were detected with a Si(Li) detector placed 4 cm from the target at 90 0 to the beam. Thick samples of NBS Standard Reference Materials were used to calibrate trace element sensitivity and estimate minimum detectable limits for this method

  3. Biological trace element measurements using synchrotron radiation

    Giauque, R.D.; Jaklevic, J.M.; Thompson, A.C.

    1985-07-01

    The feasibility of performing x-ray fluorescence trace element determinations at concentrations substantially below the ppM level for biological materials is demonstrated. Conditions for achieving optimum sensitivity were ascertained. Results achieved for five standard reference materials were, in most cases, in excellent agreement with listed values. Minimum detectable limits of 20 ppM were measured for most elements

  4. Trace element inhibition of phytase activity.

    Santos, T; Connolly, C; Murphy, R

    2015-02-01

    Nowadays, 70 % of global monogastric feeds contains an exogenous phytase. Phytase supplementation has enabled a more efficient utilisation of phytate phosphorous (P) and reduction of P pollution. Trace minerals, such as iron (Fe), zinc (Zn), copper (Cu) and manganese (Mn) are essential for maintaining health and immunity as well as being involved in animal growth, production and reproduction. Exogenous sources of phytase and trace elements are regularly supplemented to monogastric diets and usually combined in a premix. However, the possibility for negative interaction between individual components within the premix is high and is often overlooked. Therefore, this initial study focused on assessing the potential in vitro interaction between inorganic and organic chelated sources of Fe, Zn, Cu and Mn with three commercially available phytase preparations. Additionally, this study has investigated if the degree of enzyme inhibition was dependent of the type of chelated sources. A highly significant relationship between phytase inhibition, trace mineral type as well as mineral source and concentration, p phytases for Fe and Zn, as well as for Cu with E. coli and Aspergillus niger phytases. Different chelate trace mineral sources demonstrated diversifying abilities to inhibit exogenous phytase activity.

  5. Human activities affecting trace gases and climate

    Braatz, B.; Ebert, C.

    1990-01-01

    The Earth's climate has been in a constant state of change throughout geologic time due to natural perturbations in the global geobiosphere. However, various human activities have the potential to cause future global warming over a relatively short amount of time. These activities, which affect the Earth's climate by altering the concentrations of trace gases in the atmosphere, include energy consumption, particularly fossil-fuel consumption; industrial processes (production and use of chlorofluorocarbons, halons, and chlorocarbons, landfilling of wastes, and cement manufacture); changes in land use patterns, particularly deforestation and biomass burning; and agricultural practices (waste burning, fertilizer usage, rice production, and animal husbandry). Population growth is an important underlying factor affecting the level of growth in each activity. This paper describes how the human activities listed above contribute to atmospheric change, the current pattern of each activity, and how levels of each activity have changed since the early part of this century

  6. Radiation-activated sensor

    Nirschl, J.C.

    1976-01-01

    A sensing system is described for use in a remote location which detects electromagnetic radiation energy, the system being self-activating, turning itself automatically on and off, as a function of radiation intensity across the detector. In essence, when no radiation is present across the detector, the system will consume no power, the switches and MOSFET discriminator being essentially in an ''off'' position. Radiation across the detector provides a current to an input capacitance which when charged turns on the switch and the MOSFET discriminator. A switch driver produces an output pulse showing the presence of radiation; the system then shuts off awaiting the next radiation input. Since the sensor system uses virtually no power unless radiation is present, it is ideally suited for use in remote environments where battery power and size is a predominant consideration. 2 claims, 3 drawing figures

  7. A FORMALISM FOR COVARIANT POLARIZED RADIATIVE TRANSPORT BY RAY TRACING

    Gammie, Charles F.; Leung, Po Kin

    2012-01-01

    We write down a covariant formalism for polarized radiative transfer appropriate for ray tracing through a turbulent plasma. The polarized radiation field is represented by the polarization tensor (coherency matrix) N αβ ≡ (a α k a* β k ), where a k is a Fourier coefficient for the vector potential. Using Maxwell's equations, the Liouville-Vlasov equation, and the WKB approximation, we show that the transport equation in vacuo is k μ ∇ μ N αβ = 0. We show that this is equivalent to Broderick and Blandford's formalism based on invariant Stokes parameters and a rotation coefficient, and suggest a modification that may reduce truncation error in some situations. Finally, we write down several alternative approaches to integrating the transfer equation.

  8. Survey of chemical speciation of trace elements using synchrotron radiation

    Gordon, B.M.

    1985-01-01

    Information concerning the chemical state of trace elements in biological systems generally has not been available. Such information for toxic elements and metals in metalloproteins could prove extremely valuable in the elucidation of their metabolism and other biological processes. The shielding of core electrons by binding electrons affect the energy required for creating inner-shell holes. Furthermore, the molecular binding and the symmetry of the local environment of an atom affect the absorption spectrum in the neighborhood of the absorption edge. X-ray absorption near-edge structure (XANES) using synchrotron radiation excitation can be used to provide chemical speciation information for trace elements at concentrations as low as 10 ppM. The structure and position of the absorption curve in the region of an edge can yield vital data about the local structure and oxidation state of the trace element in question. Data are most easily interpreted by comparing the observed edge structure and position with those of model compounds of the element covering the entire range of possible oxidation states. Examples of such analyses are reviewed. 14 refs., 1 fig

  9. Application of synchrotron radiation to x-ray fluorescence analysis of trace elements

    Gordon, B.M.; Jones, K.W.; Hanson, A.L.

    1986-08-01

    The development of synchrotron radiation x-ray sources has provided the means to greatly extend the capabilities of x-ray fluorescence analysis for determinations of trace element concentrations. A brief description of synchrotron radiation properties provides a background for a discussion of the improved detection limits compared to existing x-ray fluorescence techniques. Calculated detection limits for x-ray microprobes with micrometer spatial resolutions are described and compared with experimental results beginning to appear from a number of laboratories. The current activities and future plans for a dedicated x-ray microprobe beam line at the National Synchrotron Light Source (NSLS) of Brookhaven National Laboratory are presented

  10. Trace elements in Australian opals using neutron activation analysis

    McOrist, G.D.; Fardy, J.J.

    1994-01-01

    Neutron activation analysis was used to determine the concentration of trace elements in 42 samples of black, grey and white opals taken from a number of recognised Australian field. The results were evaluated to determine if a relationship exited between trace element content and opal colour. (author) 12 refs.; 12 figs.; 3 tabs

  11. Probing Trace-elements in Bitumen by Neutron Activation Analysis

    Nahar, S.N.; Schmets, A.J.M.; Scarpas, Athanasios

    Trace elements and their concentrations play an important role in both chemical and physical properties of bitumen. Instrumental Neutron Activation Analysis (INAA) has been applied to determine the concentration of trace elements in bitumen. This method requires irradiation of the material with

  12. Potential interferences inherent in neutron-activation analysis of trace elements in biological materials

    Cornells, R.; Hoste, J.; Versieck, J.

    1982-01-01

    A comprehensive review is given of how neutron-activation analysis for trace elements in biological matrices can be jeopardized by radiation damage, by the impurities present in the packing material or by nuclear interferences of major elements. Systematic errors during the counting process and the quantitative interpretation of the γ-ray spectra should not be disregarded. (author)

  13. Radiation traces in exportation food samples of Parana State, Brazil

    Scheibel, Viviane

    2002-02-01

    This work deals with radioactive traces measurements in foodstuffs produced at the State of Parana, with large export rate and also of nutritious products of some regional trading companies. The measured foods were: sulfite treated sugar, tea, mint candy, soy in grain, soy crumb, gross soy oil, gum free oil and commercial refined soy oil. Six samples of each lot of the analyzed material were prepared, which represent a sampling with 90% of confidence. The samples were sealed in Marinelli beaker of 2.1 L completely filled and kept during 40 days until secular equilibrium was achieved. The counting time for each measure was of 48 hours. Measurements were carried out by gamma-ray spectrometry employing a HPGe detector with 10% of relative efficiency, coupled to standard nuclear electronics and a 8 l multichannel card. The acquisition of the data was accomplished with the software Maestro TM , version 3.2. The energy resolution of the 137 Cs 661.62 keV gamma line was 1.75 keV. The larger intensity gamma lines observed in the spectra were from the following radionuclides: 228 Ac, 208 Tl, 212 Pb of the 232 Th series, 214 Bi and 214 Pb from the 238 U series, 227 Ac from the 235 U series and 40 K. Activities and lower level of detection limits were calculated according to the International Agency of Atomic Energy norms.The detector efficiency was measured using a 152 Eu certified source and IAEA-375 and IAEA-326 certified reference materials. For most of the radionuclides it was possible only the measurement of the minimum activity detectable in the foodstuffs. Self-attenuation corrections were accomplished with support literature results. The most important activity observed was that of 40 K, whose value measured for soy in natura was 745.0 + - 9 .1 Bq/kg and for the crumb soy 1473 ± 15 Bq/kg.. he measured activities of the several analyzed foods were compatible with the values expected for non contaminated normal environmental samples, except for soy crumb, whose 40 K

  14. Trace elements in coloured opals using neutron activation analysis

    McOrist, G.D.; Smallwood, A.

    1995-01-01

    Neutron activation analysis was used to determine the concentration of trace elements in 50 samples of orange, yellow, honey, green, blue and pink opals as well as 18 samples of colourless opals taken from a number of recognised fields in Australia, Peru, Mexico and USA. The results were evaluated to determine the relationship between trace elements content and opal colour. (author). 10 refs., 10 figs., 3 tabs

  15. Polarization ray tracing in anisotropic optically active media. I. Algorithms

    McClain, S.C.; Hillman, L.W.; Chipman, R.A.

    1993-01-01

    Procedures for performing polarization ray tracing through birefringent media are presented in a form compatible with the standard methods of geometrical ray tracing. The birefringent materials treated include the following: anisotropic optically active materials such as quartz, non-optically active uniaxial materials such as calcite, and isotropic optically active materials such as mercury sulfide and organic liquids. Refraction and reflection algorithms are presented that compute both ray directions and wave directions. Methods for computing polarization modes, refractive indices, optical path lengths, and Fresnel transmission and reflection coefficients are also specified. A numerical example of these algorithms is given for analyzing the field of view of a quartz rotator. 37 refs., 3 figs

  16. Ray tracing of auroral Z mode radiation, AKR and auroral hiss

    Horne, R.B.; Jones, D.; Kimura, I.; Sawada, A.

    1990-01-01

    While observed frequency bandwidths of auroral Z mode radiation cannot be directly accounted for in terms of direct cyclotron maser instability generation, ray tracing in a hot plasma indicates that if the radiation near a plasma frequency lower than the gyrofrequency, the observed bandwidths are explainable in terms of upward propagation away from the earth. An auroral Z-mode generation mechanism is proposed involving mode conversion from O-mode auroral kilometric radiation (AKR) at the plasma frequency, as well as mode conversion from upgoing auroral hiss. Ray tracings in the O mode identify a possible AKR source region along L = 8.55. 11 refs

  17. Trace elements in coloured opals using neutron activation analysis

    McOrist, G.D.; Smallwood, A. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

    1996-12-31

    Neutron activation analysis (NAA) is a technique particularly suited to analysing opals since it is non-destructive and the silica matrix of opals is not prone to significant activation. It was used to determine the concentration of trace elements in 50 samples of orange, yellow, green, blue and pink opals as well as 18 samples of colourless opals taken from a number of recognised fields in Australia, Peru, Mexico and USA. The results were then evaluated to determine if a relationship existed between trace element content and opal colour. The mean concentration of most of the elements found in orange, yellow and colourless opals were similar with few exceptions. This indicated that, for these samples, colour is not related to the trace elements present. However, the trace element profile of the green, pink and blue opals was found to be significantly different with each colour having a much higher concentration of certain trace elements when compared with all other opals analysed. 7 refs.

  18. Trace elements in coloured opals using neutron activation analysis

    McOrist, G.D.; Smallwood, A.

    1996-01-01

    Neutron activation analysis (NAA) is a technique particularly suited to analysing opals since it is non-destructive and the silica matrix of opals is not prone to significant activation. It was used to determine the concentration of trace elements in 50 samples of orange, yellow, green, blue and pink opals as well as 18 samples of colourless opals taken from a number of recognised fields in Australia, Peru, Mexico and USA. The results were then evaluated to determine if a relationship existed between trace element content and opal colour. The mean concentration of most of the elements found in orange, yellow and colourless opals were similar with few exceptions. This indicated that, for these samples, colour is not related to the trace elements present. However, the trace element profile of the green, pink and blue opals was found to be significantly different with each colour having a much higher concentration of certain trace elements when compared with all other opals analysed. 7 refs

  19. Trace elements in coloured opals using neutron activation analysis

    McOrist, G D; Smallwood, A [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

    1997-12-31

    Neutron activation analysis (NAA) is a technique particularly suited to analysing opals since it is non-destructive and the silica matrix of opals is not prone to significant activation. It was used to determine the concentration of trace elements in 50 samples of orange, yellow, green, blue and pink opals as well as 18 samples of colourless opals taken from a number of recognised fields in Australia, Peru, Mexico and USA. The results were then evaluated to determine if a relationship existed between trace element content and opal colour. The mean concentration of most of the elements found in orange, yellow and colourless opals were similar with few exceptions. This indicated that, for these samples, colour is not related to the trace elements present. However, the trace element profile of the green, pink and blue opals was found to be significantly different with each colour having a much higher concentration of certain trace elements when compared with all other opals analysed. 7 refs.

  20. Radiation-induced decomposition of trace amounts of 17 β-estradiol in water

    Kimura, Atsushi; Taguchi, Mitsumasa; Arai, Hidehiko; Hiratsuka, Hiroshi; Namba, Hideki; Kojima, Takuji

    2004-01-01

    The radiation-induced decomposition of trace amounts of 17 β-estradiol (E2) in water was studied as a function of the dose of 60 Co γ-rays. The rate constant of the reaction of the OH radicals with E2 was estimated to be 1.6x10 10 mol dm -3 s -1 by a comparison with the known rate constant for the reaction with phenol. Both E2 and E2-equivalent concentrations were estimated by LC-MS and ELISA, and decreased with an increase in γ-rays dose. E2 (1.8 nmol dm -3 ) in water was degraded almost completely by irradiations up to 10 Gy. The estrogen activity of the same sample solution still remained at a dose of 10 Gy, but decreased at 30 Gy to the lower than the threshold level of contamination to induce some estrogenic effects on the environmental ecology

  1. Bejing synchrotron radiation TXRF facility and its applications on trace element study of cells

    Yuying, H.; Yingrong, W.; Limin, Z.; Guangcheng, L.; Wie, H.

    2000-01-01

    In this paper, Beijing synchrotron radiation TXRF facility and experimental method were described. The minimum detection limits of some elements were tested by using several kinds of standard reference materials. The feasibility of using TXRF in biomedical field is discussed. With this technique small intestine cells of both normal and radiated white mice were analyzed, and the elemental average contents of each single cell are also given. The results indicated that the contents of some trace elements for normal and radiated white mice are greatly different, which may be used to provide valuable reference for clinic medicine. On the other hand, the trace elements of cells of lung and cervix cancer before and after apoptosis were determined by SRTXRF and the changes of trace elements in these cells were discussed. (author)

  2. Effects of trace elements on urease activity in soils

    Tabatabai, M A

    1977-01-01

    Disposal of sewage sludges and effluents on agricultural land is becoming a widespread practice. Most sludge samples disposed on soils contain large quantities of various trace elements. Studies of 20 trace elements commonly found in sludge samples showed that they inhibit the activity of urease in soils and that their order of effectiveness as inhibitors of urease depends on the soil. When the trace elements were compared by using 5 ..mu..mol . g/sup -1/ soil, however, some of them showed the same order of effectiveness as urease inhibitors in the six soils studied i.e., for the monovalent and divalent ions. Ag/sup +/ greater than or equal to Hg/sup 2 +/ > Cu/sup 2 +/ > Cd/sup 2 +/ > Zn/sup 2 +/ > Sn/sup 2 +/ > Mn/sup 2 +/, and generally, Fe/sup 3 +/ > Fe/sup 2 +/ and Cu/sup 2 +/ > Cu/sup +/. Other trace element ions that inhibited urease were Ni/sup 2 +/, Co/sup 2 +/, Pb/sup 2 +/, Ba/sup 2 +/, As/sup 3 +/, B/sup 3 +/, Cr/sup 3 +/, Al/sup 3 +/, V/sup 4 +/, Se/sup 4 +/, and Mo/sup 6 +/. Of the trace element ions studied, only As/sup 5 +/ and W/sup 6 +/ did not inhibit urease activity in soils. Studies on the distribution of urease activity showed that it is concentrated in surface soils and decreases with depth. Urease activity was proportional to organic C distribution in each soil profile and was significantly correlated with organic C in the surface soils studied.

  3. Assessing radiation exposure of herbaceous plant species at the East-Ural Radioactive Trace

    Karimullina, Elina; Antonova, Elena; Pozolotina, Vera

    2013-01-01

    The East-Ural Radioactive Trace (EURT) is a result of the Mayak Production Association accident that occurred in 1957 in Russia. Radiological assessment improves the interpretation of biological effects of exposure to ionizing radiation. Therefore a modeling approach was used to estimate dose rates on Leonurus quinquelobatus, Silene latifolia, Stellaria graminea and Bromus inermis. Soil-to-organism transfer parameter values are delivered from empirical data of 90 Sr and 137 Cs soil and vegetative plant mass activity concentrations. External and internal whole-body dose rates were calculated using deterministic (The ERICA Tool-Tier 2 and R and D 128/SP1a) and probabilistic (The ERICA Tool-Tier 3) methods. The total dose rate for herbs was under 100 μGy h −1 at the most polluted site. The total absorbed dose rates increased 43–110 times (Tier 3) for different herbaceous plant species along the pollution gradient. Based on these data, it can be concluded that herbaceous plant populations currently exist under low-level chronic exposure at the EURT area. -- Highlights: • A modeling approach (The ERICA Tool-Tier 2, Tier 3 and R and D 128/SP1a) was used to estimate dose rates for herbs growing in the wild at the East-Ural Radioactive Trace. • The highest levels of anthropogenic radiation exposure were determined for herbs at Impact EURT sites. • Total absorbed dose rates increased 43–110 times (Tier 3) for different herbaceous plant species along the pollution gradient. • Total dose rate per plant organism for herbs is under 100 μGy h −1 at the most polluted site. Currently herbaceous plant populations exist under low-level chronic exposure at the EURT area

  4. Activities of Radiation Standard Section

    Kannan, A.; Rao, P.S.; Sachadev, R.N.; Shaha, V.V.; Sharma, D.; Srivastava, P.K.

    1992-01-01

    A brief account of the various facilities and services provided by the Radiation Standards Section (RSS) of the Bhabha Atomic Research Centre, Bombay is given. RSS maintains the primary and secondary standards of various parameters of radiation measurements. It ensures accurate radiological measurements as per international requirements, through periodic international intercomparisons of national standards. It also provides calibration services to various users of radiation sources and instruments. The activities of RSS are described under the headings: (1) Radiological Metrology Standards, (2) Radionuclide Standards, Neutron Metrology, (4) Instruments Calibration, (5) Non-ionizing Radiations, and (6) Instrumentation. (author). figs., tabs

  5. Fast voxel and polygon ray-tracing algorithms in intensity modulated radiation therapy treatment planning

    Fox, Christopher; Romeijn, H. Edwin; Dempsey, James F.

    2006-01-01

    We present work on combining three algorithms to improve ray-tracing efficiency in radiation therapy dose computation. The three algorithms include: An improved point-in-polygon algorithm, incremental voxel ray tracing algorithm, and stereographic projection of beamlets for voxel truncation. The point-in-polygon and incremental voxel ray-tracing algorithms have been used in computer graphics and nuclear medicine applications while the stereographic projection algorithm was developed by our group. These algorithms demonstrate significant improvements over the current standard algorithms in peer reviewed literature, i.e., the polygon and voxel ray-tracing algorithms of Siddon for voxel classification (point-in-polygon testing) and dose computation, respectively, and radius testing for voxel truncation. The presented polygon ray-tracing technique was tested on 10 intensity modulated radiation therapy (IMRT) treatment planning cases that required the classification of between 0.58 and 2.0 million voxels on a 2.5 mm isotropic dose grid into 1-4 targets and 5-14 structures represented as extruded polygons (a.k.a. Siddon prisms). Incremental voxel ray tracing and voxel truncation employing virtual stereographic projection was tested on the same IMRT treatment planning cases where voxel dose was required for 230-2400 beamlets using a finite-size pencil-beam algorithm. Between a 100 and 360 fold cpu time improvement over Siddon's method was observed for the polygon ray-tracing algorithm to perform classification of voxels for target and structure membership. Between a 2.6 and 3.1 fold reduction in cpu time over current algorithms was found for the implementation of incremental ray tracing. Additionally, voxel truncation via stereographic projection was observed to be 11-25 times faster than the radial-testing beamlet extent approach and was further improved 1.7-2.0 fold through point-classification using the method of translation over the cross product technique

  6. Neutron activation analysis of trace elements in biological tissue

    Velandia, J A; Perkons, A K

    1974-01-01

    Thermal Neutron Activation Analysis with Instrumental Ge(Li) Gamma Spectrometry was used to determine the amounts of more than 30 trace constituents in heart tissue of rats and kidney tissue of rabbits. The results were confirmed by a rapid ion-exchange group separation method in the initial stages of the experiments. The samples were exposed to thermal neutrons for periods between 3 minutes and 14 hours. Significant differences in the amounts and types of trace elements in the two different tissue types are apparent, however, are probably due to specific diets. Tables of relevant nuclear data, standard concentrations, radiochemical separation recoveries, and quantitative analytical results are presented. The ion-exchange group separation scheme and typical examples of the instrumental gamma ray spectra are shown. The techniques developed in this study are being used for a large scale constituent survey of various diseased and healthy human tissues.

  7. Chelatable trace zinc causes low, irreproducible KDAC8 activity.

    Toro, Tasha B; Edenfield, Samantha A; Hylton, Brandon J; Watt, Terry J

    2018-01-01

    Acetylation is an important regulatory mechanism in cells, and emphasis is being placed on identifying substrates and small molecule modulators of this post-translational modification. However, the reported in vitro activity of the lysine deacetylase KDAC8 is inconsistent across experimental setups, even with the same substrate, complicating progress in the field. We detected trace levels of zinc, a known inhibitor of KDAC8 when present in excess, even in high-quality buffer reagents, at concentrations that are sufficient to significantly inhibit the enzyme under common reaction conditions. We hypothesized that trace zinc in solution could account for the observed variability in KDAC8 activity. We demonstrate that addition of chelators, including BSA, EDTA, and citrate, and/or the use of a phosphate-based buffer instead of the more common tris-based buffer, eliminates the inhibition from low levels of zinc as well as the dependence of specific activity on enzyme concentration. This results in high KDAC8 activity that is consistent across buffer systems, even using low concentrations of enzyme. We report conditions that are suitable for several assays to increase both enzyme activity and reproducibility. Our results have significant implications for approaches used to identify substrates and small molecule modulators of KDAC8 and interpretation of existing data. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Trace elements and antibacterial activity in amniotic fluid.

    Honkonen, E; Näntö, V; Hyörä, H; Vuorinen, K; Erkkola, R

    1986-01-01

    Antibacterial activity and trace element concentrations in amniotic fluid (AF) were determined in a population of 39 pregnant women in the second half of gestation. Antibacterial activity in each AF was measured by a spectrophotometric micromethod after 18 h incubation at 37 degrees C using Escherichia coli K 12 as a reference bacterium. Concentrations of zinc, iron, copper, calcium, potassium and bromine were measured by particle-induced X-ray emission method and the zinc concentration was also measured by atomic absorption spectrophotometry. Phosphate concentration was determined by direct albumin adding method. In AFs with good antibacterial activity significantly lower concentrations of potassium and bromine were found when compared to AFs with lower antibacterial activity. Concentrations of zinc, iron, copper, calcium or phosphate did not correlate with antibacterial activity in AF.

  9. Neutron-activation analysis of trace elements in thyroids

    Boulyga, S.F.; Petri, H.; Kanash, N.V.; Malenchenko, A.F.

    1999-01-01

    Neutron activation analysis was used for routine measurement of trace elements in thyroids of inhabitants of Belarus as well as in thyroids of people operated for thyroid cancer. The method chosen allowed the analysis of 28 elements, among them essential and toxic ones, with a good accuracy. The results obtained showed significant differences in the elemental composition of thyroid from the different regions. The changes of elemental composition of thyroids of inhabitants of the Gomel region, where goiter is endemic, seem to be identical to those in the tumor tissue. (author)

  10. Neutron activation analysis of trace elements in IAEA reference materials

    Cheema, M.N.; Hasany, S.M.; Hanif, I.; Chaudhry, M.S.; Qureshi, I.H.

    1978-09-01

    Analytical Chemistry Group of Nuclear Chemistry Division at PINSTECH has been participating in IAEA Intercomparison programme of analytical quality control since 1972. So far fifteen samples of a variety of materials received from the Agency have been analyzed for different minor and trace elements. Mostly destructive and non-destructive neutron activation analysis techniques have been used for elemental analysis. In this report the description of the samples and the experimental procedures employed have been mentioned. The results of elemental analysis have been reported and compared with IAEA values which are based on the average computed from the results of different participating laboratories. (authors)

  11. Tracing salmon to their birthplace by activable tracer technique

    Shibuya, Masao

    1978-01-01

    Activable tracer technique was applied to trace the recurrent migration of white salmons, as a typical example of employing radioactivation analysis to the study of agricultural and marinefields. Europium was adopted because it is easy to use technically with less influence on fish body and easy to detect, and its remaining time is very long. Artificially hatched young white salmons were stocked in the Saibetsu River after being raised for a month with europium-containing feed. These stocked fish were labeled by fin-cutting method. Recurrent salmons (fin cutting-labeled fish) were then collected and dissected. The fishes were divided into otoliths, scales, flesh, internal organs, gills, bones, etc., and irradiated for 5 min in JRR-2 reactor of Japan Atomic Energy Research Institute. Europium was detected from the scales and otoliths of 3 to 4 year stocked adult fishes by γ-spectrometry of Eu. This proved the availability of activable tracer method for tracing the recurrent migration of salmons. (Kobatake, H.)

  12. Neutron activation analysis of trace elements in foodstuffs

    Schelenz, R.; Fischer, E.

    1976-05-01

    A neutron activation method for multielement determination in biological material was developed. The individual steps of the method include radiochemical processing as well as nondestructive techniques. In order to develop a high resolution gamma spectrometric method the indispensable assumptions were the application of Ge(Li)-semiconductor detectors, multi-channel pulse height analyzers and the use of electronic data evaluation with mini-computers for the automatic evaluation of complex gamma spectra. After radiochemical separation (RNAA) 33 elements can be determined in biological materials and by application of nondestructive, purely instrumental techniques (INAA) 25 elements. The time required for the analysis of 33 elements can be determined in biological materials and by application of nondestructive, purely instrumental techniques (INAA) 25 elements. The time required for the analysis of 33 elements is 4 days. The neutron activation method is used routinely for the determination of trace elements in foodstuffs and in the field of nutrition research. (orig.) [de

  13. Uncertainties in measuring trace amounts of cobalt and europium with low-flux neutron activation analysis

    Burnham Steven

    2017-01-01

    Full Text Available Neutron activation analysis is widely used for identification of elements and their quantities even in trace amounts in the samples of almost any type. The challenges in detecting trace amounts of particular elements are often associated with the neutron flux produced at the research reactors. Low-flux neutron activation analysis usually presents the biggest challenge when analyzing trace quantities of elements with lower magnitude of radiative capture cross-sections. In this paper, we present the methodology and the quantified uncertainties associated with the detection of trace amounts of cobalt and europium, using as an example concrete aggregates. Recent growing interest is in improving structural concrete (increasing its strength but reducing its activation in nuclear power plant environments. Aside from buildings, structural concrete is also used as a biological shield in nuclear power plant that become radioactive after exposure to neutron flux. Due to radiative capture interactions, artificial radionuclides are generated to high enough concentrations that classify concrete as low-level radioactive waste at the time of the plant's decommissioning. Disposal of this concrete adds to the expense of nuclear power plant financing and its construction. Three radionuclides, 60Co, 152Eu, and 154Eu, account for 99 % of total residual radioactivity of nuclear power plant decommissioned concrete. IAEA document RS-G-1.7, Application of the Concepts of Exclusion, Exemption, and Clearance, specifies clearance levels of radionuclides specific activities: a specific activity lower than 0.1 Bqg-1 for 60Co and 152Eu, and 154Eu allows for a concrete to be recycled after decommissioning of the nuclear power plant. Therefore, low-flux neutron activation analysis is used to test the detection limits of trace elements in samples of cement, coarse, and fine concrete aggregates. These samples are irradiated at the University of Utah's 100 kW TRIGA Reactor at

  14. Neutron activation analysis for bulk and trace elements in urine

    Cornelis, R.; Speecke, A.; Hoste, J.

    1975-01-01

    Problems in sampling urine for trace element analysis by neutron activation are systematically examined. Collection, storage, sample preparation and contamination hazards during irradiation are studied in detail. Three different sizes of urine samples are prepared for analysis, depending on the concentration and nuclear properties of the elements, and suitable multielement doped urine standards are used. As, Br, Ca, Cl, Co, Cr, Cs, Cu, Hg, I, K, Mg, Mn, Na, Rb, Se and Zn are determined. The extreme care given to sample collection, use of ''ultra-clean'' vials, and work in a dust-free room allows consistent values to be obtained over long periods of time. A literature review of the amounts of forty elements present in urine per day is also given

  15. Study of trace impurities in heroin by neutron activation analysis

    Zhang, Z.Y.; Yang, J.H.; Ouyang, H.; Li, Z.J.; Chai, Z.F.; Zhu, J.; Xi'an JiaoTong Univ., Shaanxi; Zhao, J.Z.; Yu, Z.S.; Wang, J.

    2004-01-01

    Sixty-two heroin samples were analyzed for their contents of 15 trace elements (Au, Ba, Br, Ca, Ce, Co, Cr, Fe, La, Na, Sb, Sc, Sm, Th, and Zn) by neutron activation analysis (NAA). Large variations of elemental concentrations between samples were found to possess statistical significance. Of all the elements calcium was the most abundant element, followed by zinc and sodium. The concentrations of Au, Ce, Co, La, Sb, Sc, Sm, and Th in all the samples were below 1 μg x g -1 . Classification of these heroin samples was achieved by the application of hierarchical cluster analysis. The results show that NAA can provide useful information on the origin of the illicit drugs. (author)

  16. Thermal radiation characteristics of nonisothermal cylindrical enclosures using a numerical ray tracing technique

    Baumeister, Joseph F.

    1990-01-01

    Analysis of energy emitted from simple or complex cavity designs can lead to intricate solutions due to nonuniform radiosity and irradiation within a cavity. A numerical ray tracing technique was applied to simulate radiation propagating within and from various cavity designs. To obtain the energy balance relationships between isothermal and nonisothermal cavity surfaces and space, the computer code NEVADA was utilized for its statistical technique applied to numerical ray tracing. The analysis method was validated by comparing results with known theoretical and limiting solutions, and the electrical resistance network method. In general, for nonisothermal cavities the performance (apparent emissivity) is a function of cylinder length-to-diameter ratio, surface emissivity, and cylinder surface temperatures. The extent of nonisothermal conditions in a cylindrical cavity significantly affects the overall cavity performance. Results are presented over a wide range of parametric variables for use as a possible design reference.

  17. Tracing How Normative Messages May Influence Physical Activity Intention.

    van Bavel, René; Esposito, Gabriele; Baranowski, Tom; Duch-Brown, Néstor

    2017-04-01

    Normative messages have been shown to increase intention to do physical activity. We traced how "positive" and "negative" normative messages influenced physical activity intention by comparing constructs of the model of goal-directed behavior with descriptive norms (MGDB + DNs) across control and treatment groups in an experiment. For this purpose, 16-24-year-old respondents (n = 1,200) in Bulgaria, Croatia, and Romania were asked about their age, sex, and levels of physical activity before being exposed to positive and negative normative messages and completing a questionnaire with MGDB + DNs scales. Different MGDB + DNs constructs were influenced by the normative messages: compared with the control, the negative message group showed stronger attitudes (p = .003) and the positive message group showed higher positive anticipated emotions (p = .005). The positive message's effect is consistent with the literature on conformity to social norms. The negative message's effect lends itself to interpretations based on social identity and deviance regulation theories.

  18. Trace concentrations of vitamin E protect radiation crosslinked UHMWPE from oxidative degradation.

    Kurtz, S M; Dumbleton, J; Siskey, R S; Wang, A; Manley, M

    2009-08-01

    The effect of very low concentrations of Vitamin E on the stability and mechanical behavior of UHMWPE remains unknown. We tested the hypothesis that the oxidation resistance of Vitamin E-blended UHMWPE would be influenced by trace doses of antioxidant, resin, and radiation treatment. Trace concentrations (Vitamin E) were blended separately with GUR 1020 and 1050 resins and molded into disks. From each disk, three groups of 10 mm thick blocks were machined: (1) no irradiation (control); (2) 30 kGy of gamma irradiation in nitrogen; and (3) 75 kGy of gamma irradiation in air. Specimens were subjected to three aging protocols: (a) no aging (control); (b) two weeks and (c) four weeks of accelerated aging in accordance with ASTM F 2003 (i.e., 70 degrees C and 5 atm oxygen). The minimum concentration of Vitamin E needed to stabilize UHMWPE during our accelerated tests depended upon the method of radiation processing. For the 30 and 75 kGy irradiated materials, the addition of 125 ppm or more Vitamin E was sufficient to maintain baseline mechanical and chemical properties through two weeks of accelerated aging. For these groups, the addition of 375 ppm or 500 ppm, respectively, was necessary to maintain baseline mechanical and chemical properties throughout the four-week accelerated aging period. UHMWPE resin molecular weight did not have an effect on oxidation behavior. The results of this experiment therefore supported our hypotheses that trace concentrations of Vitamin E, coupled with radiation treatment-but not resin grade-influence the mechanical and oxidative degradation behavior of UHMWPE.

  19. Neutron activation analysis of trace elements in foodstuffs

    Schelenz, R.; Bayat, I.; Fischer, E.

    1976-05-01

    For the determination of trace elements in foodstuffs with the aid of neutron activation analysis the separation of volatile radionuclides after digestion of the sample is of special interest for radiochemical processing. A distillation procedure was developed to give reproducable results, however optimal conditions were not found for all volatile radionuclides studied. The required selective separation of Br-82 from the distillate was best achieved by the application of an ion-exchange column-chromatography technique. The computer programs for the evaluation of complex gamma spectra have been developed further. The automatic peak search and peak area determination is based on a computer program using the correlation technique and carried out with a mini-computer coupled with a multi-channel gamma spectrometer. The results, which are presented in 3 earlier reports relating to this research program, reveal the advantages and disadvantages of the individual steps of the radiochemical separation scheme. Before neutron activation analysis can be introduced on a routine basis, some aspects of the radiochemical process remain to be tested; these studies will be published in a fourth and final report. (orig.) [de

  20. Radiation processing activities at OGFL

    Sarkar, Atish

    2014-01-01

    CONCAST group of Industries has set up the first Radiation Processing Plant in Eastern India as 'VIKIRAN' named as Organic Green Foods Ltd., situated at Dankuni (Durgapur Highway Express) 25 km away from central Kolkata on August 21, 2004. Shri Sanjay Sureka, Managing Director of Organic Green Foods Ltd., Kolkata belongs to the famous CONCAST Group of Industries operates the largest plant of West Bengal engaged in manufacturing of Steel Industry. The facility was aimed at improving the quality of healthcare products and devices as well as Laboratory, Spice, Herbal and Ayurvedic Products of large volumes on an industrial scale. The operation of VIKIRAN for the last ten years, has unambiguously proved that both the above objectives have been fully met and now radiation sterilization has emerged as an efficient and effective industrial process. The irradiator is a panoramic wet storage class-IV type. This Facility is designed for 1000 KCi activity of source and is suitable in medium and high dose range application. VIKIRAN offers radiation sterilization service to more than 100 manufacturers

  1. Neutron activation analysis of trace elements in rain water

    Luten, J.B.

    1977-01-01

    In this thesis the principles and practical aspects of activation analysis which are of direct importance in the analysis of rain water, are presented together with recent literature data on other techniques. Problems due to the storage of rain water samples are discussed. A multi-element method for the determination of trace elements in rain water by instrumental neutron activation analysis is described. Gamma ray spectrometry using Ge(Li) detectors offers the possibility to determine Na, Al, Cl, V, Mn, Co, Cu, Br and I in rain water samples of 2.5 ml after a 4-min irradiation in a thermal neutron flux of 5 x 10 13 n cm -2 s -1 . In residues of rain water samples of 100 ml, irradiated during 2 days in a thermal neutron flux of >5 x 10 13 n cm -2 s -1 Cr, Fe, Co, Zn and Sb can be determined after a cooling period of approximately 21 days. The detection limits are lower than those reported in previous investigations except for Cu. The precision is about 10% or better, except for Co, Cu and I. A routine method for the determination of bromine and iodine in rain water by n.a.a. is presented. The elements are isolated by isotope exchange between the irradiated sample and a solution of Br 2 or I 2 in CCl 4 . The method is not sensitive to the chemical species in which the halogen is present. Irradiation of solutions of iodine compounds in a high thermal neutron flux gives rise to the formation of iodate. Results of a further investigation of this phenomenon are given, as well as the determination of iodate in rain water by n.a.a. Iodate is separated by anion exchange. The combination of n.a.a. and solvent extraction is used for the determination of five trace elements (V, Co, Cu, Zn and In) in 10-ml rain water samples. For V, Co and Cu this method is more sensitive and reproducible than instrumental n.a.a. The results of the analysis of eleven sequential 30-ml samples from the beginning of the shower are presented as an illustration of possible applications of the

  2. Fast solar radiation pressure modelling with ray tracing and multiple reflections

    Li, Zhen; Ziebart, Marek; Bhattarai, Santosh; Harrison, David; Grey, Stuart

    2018-05-01

    Physics based SRP (Solar Radiation Pressure) models using ray tracing methods are powerful tools when modelling the forces on complex real world space vehicles. Currently high resolution (1 mm) ray tracing with secondary intersections is done on high performance computers at UCL (University College London). This study introduces the BVH (Bounding Volume Hierarchy) into the ray tracing approach for physics based SRP modelling and makes it possible to run high resolution analysis on personal computers. The ray tracer is both general and efficient enough to cope with the complex shape of satellites and multiple reflections (three or more, with no upper limit). In this study, the traditional ray tracing technique is introduced in the first place and then the BVH is integrated into the ray tracing. Four aspects of the ray tracer were tested for investigating the performance including runtime, accuracy, the effects of multiple reflections and the effects of pixel array resolution.Test results in runtime on GPS IIR and Galileo IOV (In Orbit Validation) satellites show that the BVH can make the force model computation 30-50 times faster. The ray tracer has an absolute accuracy of several nanonewtons by comparing the test results for spheres and planes with the analytical computations. The multiple reflection effects are investigated both in the intersection number and acceleration on GPS IIR, Galileo IOV and Sentinel-1 spacecraft. Considering the number of intersections, the 3rd reflection can capture 99.12 %, 99.14 % , and 91.34 % of the total reflections for GPS IIR, Galileo IOV satellite bus and the Sentinel-1 spacecraft respectively. In terms of the multiple reflection effects on the acceleration, the secondary reflection effect for Galileo IOV satellite and Sentinel-1 can reach 0.2 nm /s2 and 0.4 nm /s2 respectively. The error percentage in the accelerations magnitude results show that the 3rd reflection should be considered in order to make it less than 0.035 % . The

  3. Simultaneous speciation neutron activation analysis for trace elements

    Chatt, A.; Kiceniuk, J.W.; Menendez Sanchez, W.; Bottaro, C.

    2006-01-01

    Among the various forms of neutron activation technique being developed in our laboratory, much emphasis has been placed over the last ten years or so on the development of simultaneous speciation neutron activation analysis (SSNAA). This technique can now be used for the simultaneous determination of various species of a number of elements. Almost all speciation techniques consist of two steps. The first step involves the separation of species from the sample followed by the second step of element-specific detection. A number of characteristic features of NAA, which other techniques normally do not possess, can be advantageously exploited in SSNAA. For example, SSNAA can be used for: (i) multielement speciation with high specificity, (ii) speciation of chemically dissimilar elements such as Cd, Mn and Se, (iii) speciation of elements such as Cl, Br and I which are rather difficult to determine by most other techniques, etc. We have developed SSNAA methods for assaying various arsenic species, namely As(III), As(V), dimethyl arsonic acid (DMA), monomethylarsinic acid (MMA), arsenobetaine (AsB), organically bound arsenic (OBAs), and lipid-soluble arsenic (LSAs) in marine fish samples. We have extended these methods to include simultaneous determination of various species of As, Sb and Se in water. We have also developed SSNAA methods employing biochemical techniques for the simultaneous separation, preconcentration and characterization of metalloproteins and protein-bound trace element species of As, Br, Cd, Cu, Mn, Se, and Zn. We have developed methods for the simultaneous separation and characterization of organohalogen compounds in fish. An overview of the SSNAA methods being developed in our laboratory will be presented. (author)

  4. Preconcentration and Speciation of Trace Elements and Trace-Element Analogues of Radionuclides by Neutron Activation Analysis

    Chatt, A.

    1999-01-01

    We have developed a number of preconcentration neutron activation analysis (PNAA) methods in our laboratory for the determination of trace elements in a variety of complex sample matrices. We developed a number of cocrystallization and coprecipitation methods for the determination of trace elements in water samples. We developed several methods for the determination of I in foods and diets. We have developed a number of PNAA methods in our laboratory We determined As and Sb in geological materials and natural waters by coprecipitation with Se and Au in silicate rocks and ores by coprecipitation with Te followed by NAA. We developed an indirect NAA method for the determination of B in leachates of borosilicate glass. We have been interested in studying the speciation of Am, Tc, and Np in simulated vitrified groundwater leachates of high-level wastes under oxid and anoxic conditions using a number of techniques. We then used PNAA methods to study speciation of trace-element analogues of radionuclides. We have been able to apply biochemical techniques and NAA for the separation, preconcentration, and characterization of metalloprotein and protein-bound trace-element species in subcellular fractions of bovine kidneys. Lately, we have concentrated our efforts to develop chemical and biochemical methods in conjunction with NAA, NMR, and MS for the separation and identification of extractable organohalogens (EOX) in tissues of beluga whales, cod, and northern pink shrimp

  5. Hybrid Active-Passive Radiation Shielding System

    National Aeronautics and Space Administration — A radiation shielding system is proposed that integrates active magnetic fields with passive shielding materials. The objective is to increase the shielding...

  6. Trace element assessment of low-alloy and stainless steels with reference to gamma activity

    Goddard, A.J.H.; Macmahon, T.D.; Gamberini, D.; Taylor, J.M.; Duggan, F.

    1984-01-01

    In order to predict the long-lived gamma activities leading to radiation exposure during dismantling operations it is necessary to know the likely trace element content of the reactor vessel and internals. This work has been concerned with measuring the elements Ni, Nb, Mo, Co, Ag, Eu, Sm and Ho in steels, with particular reference to light-water reactors. Various steel samples have been provided by organizations in Europe. Analyses have been carried out principally by neutron activation analysis, but also by atomic absorption (AA), inductively coupled plasma (ICP) and secondary ion microprobe spectrometry (SIMS). Analyses for Ni, Mo and Co were straightforward and results agreed with analyses carried out elsewhere. A variety of techniques were employed for Nb; ICP was the most successful and results were confirmed using SIMS. In the case of Ag only flameless AA yielded results for all samples. The low concentration of rare earth elements required the development of a preliminary ion exchange technique. Low-alloy steels examined had Nb concentrations less than 10 ppm. Ag levels in the vicinity of 1 ppm were found in all steel samples, indicating that Ag may be the most significant element at long cooling times. Rare earth concentrations from this and other work indicate that these elements are unlikely to give gamma activities exceeding those of 60 Co, 59 Ni, sup(108m)Ag and 94 Nb activities. Illustrative gamma activity decay calculations using the Origen code are presented

  7. Radiation heat transfer model in a spent fuel pool by TRACE code

    Sanchez-Saez, F.; Carlos, S.; Villanueva, J.F.; Martorell, S.

    2014-01-01

    Nuclear policies have experienced an important change since Fukushima Daiichi nuclear plant accident and the safety of spent fuels has been in the spot issue among all the safety concerns. The work presented consists of the thermohydraulic simulation of spent fuel pool behavior after a loss of coolant throughout transfer channel with loss of cooling transient is produced. The simulation is done with the TRACE code. One of the most important variables that define the behavior of the pool is cladding temperature, which evolution depends on the heat emission. In this work convection and radiation heat transfer is considered. When both heat transfer models are considered, a clear delay in achieving the maximum peak cladding temperature (1477 K) is observed compared with the simulation in which only convection heat transfer is considered. (authors)

  8. Interfering line in trace analysis by X-ray spectrometry: Radiative auger satellites

    Maeda, Kuniko; Kawai, Jun.

    1994-01-01

    Strong characteristic X-ray lines (e.g. Kα and Kβ) are accompanied by broad low-energy satellites caused by the radiative Auger effect (RAE). In order to prove how the RAE satellites interfere the analysis of minor elements, low-energy side spectra of Ca and Ti Kβ, and Ca-Fe Kα were measured. The obtained RAE intensities are summarized together with published experimental and theoretical data. The integrated intensities of satellites due to K → MM, K → LM and K → LL RAE relative to that of Kα are determined to be of the order of 0.01-0.1%. This warns that the neglecting of the RAE satellites will introduce a serious error in trace analysis. (author)

  9. Activation of human immunodeficiency virus by radiation

    Beer, J.Z.; Zmudzka, B.Z.

    1991-01-01

    It was recently demonstrated that ultraviolet radiation (UVR) can induce the HIV promoter as well as activate the complete virus in cultured cells (Valerie et al., 1988). This and subsequent observations, reviewed in this article, suggest a possibility that radiation exposure may accelerate development of AIDS in HIV-infected individuals. They also indicate that studies on HIV activation by stressors, including radiation, may advance our understanding of some phenomena that follow HIV infection. (author)

  10. Radiation shielding activities at IDOM

    Ordóñez, César Hueso; Gurpegui, Unai Cano; Valiente, Yelko Chento; Poveda, Imanol Zamora, E-mail: cesar.hueso@idom.com [IDOM, Consulting, Engineering and Architecture, S.A.U, Vizcaya (Spain)

    2017-07-01

    When human activities have to be performed under ionising radiation environments the safety of the workers must be guaranteed. Usually three principles are used to accomplish with ALARA (As Low As Reasonably Achievable) requirements: the more distance between the source term and the worker, the better; the less time spent to arrange any task, the better; and, once the previous principles are optimized should the exposure of the workers continues being above the regulatory limits, shielding has to be implemented. Through this paper some different examples of IDOM's shielding design activities are presented. Beginning with the gamma collimators for the Jules Horowitz Reactor, nuclear fuel's behaviour researching facility, where the beam path crosses the reactor's containment walls and is steered up to a gamma detector where the fuel spectrum is analysed and where the beam has to be attenuated several orders of magnitude in a short distance. Later it is shown IDOM’s approach for the shielding of the Emergency Control Management Center of Asociación Nuclear Ascó-Vandellòs-II NPPs, a bunker designed to withstand severe accident conditions and to support the involved staff during 30 days, considering the outside radioactive cloud and the inside source term that filtering units become as they filter the incoming air. And finally, a general approach to this kind of problems is presented, since the study of the source term considering all the possible contributions, passing through the material selection and the thicknesses calculation until the optimization of the materials. (author)

  11. Radiation shielding activities at IDOM

    Ordóñez, César Hueso; Gurpegui, Unai Cano; Valiente, Yelko Chento; Poveda, Imanol Zamora

    2017-01-01

    When human activities have to be performed under ionising radiation environments the safety of the workers must be guaranteed. Usually three principles are used to accomplish with ALARA (As Low As Reasonably Achievable) requirements: the more distance between the source term and the worker, the better; the less time spent to arrange any task, the better; and, once the previous principles are optimized should the exposure of the workers continues being above the regulatory limits, shielding has to be implemented. Through this paper some different examples of IDOM's shielding design activities are presented. Beginning with the gamma collimators for the Jules Horowitz Reactor, nuclear fuel's behaviour researching facility, where the beam path crosses the reactor's containment walls and is steered up to a gamma detector where the fuel spectrum is analysed and where the beam has to be attenuated several orders of magnitude in a short distance. Later it is shown IDOM’s approach for the shielding of the Emergency Control Management Center of Asociación Nuclear Ascó-Vandellòs-II NPPs, a bunker designed to withstand severe accident conditions and to support the involved staff during 30 days, considering the outside radioactive cloud and the inside source term that filtering units become as they filter the incoming air. And finally, a general approach to this kind of problems is presented, since the study of the source term considering all the possible contributions, passing through the material selection and the thicknesses calculation until the optimization of the materials. (author)

  12. Radiation protection, 1975. Annual EPA review of radiation protection activities

    1976-06-01

    The EPA, under its Federal Guidance authorities, is responsible for advising the President on all matters pertaining to radiation and, through this mechanism, to provide guidance to other Federal agencies on radiation protection matters. Highlights are presented of significant radiation protection activities of all Federal agencies which were completed in 1975, or in which noteworthy progress was made during that period, and those events affecting members of the public. State or local activities are also presented where the effects of those events may be more far-reaching. At the Federal level significant strides have been made in reducing unnecessary radiation exposure through the efforts of the responsible agencies. These efforts have resulted in the promulgation of certain standards, criteria and guides. Improved control technologies in many areas make it feasible to reduce emissions at a reasonable cost to levels below current standards and guides. This report provides information on the significant activities leading to the establishment of the necessary controls for protection of public health and the environment. Radiation protection activities have been undertaken in other areas such as medical, occupational and consumer product radiation. In the context of radiation protection, ancillary activities are included in this report in order to present a comprehensive overview of the events that took place in 1975 that could have an effect on public health, either directly or indirectly. Reports of routine or continuing radiation protection operations may be found in publications of the sponsoring Federal agencies, as can more detailed information about activities reported in this document. A list of some of these reports is included

  13. The Possible Protective Role of Green Tea against Radiation induced Certain Biochemical and Trace Element Changes in Rats

    Hanna, M.M.A.

    2012-01-01

    The process of ionization occurring after radiation energy absorption in atoms and molecules of biological matter results in biochemical alterations, which cause damage to cellular elements. This damage is mediated through generation of reactive oxygen species (ROS) that in turn damage proteins, lipids, nucleic-acids and trace elements. They also can attack poly unsaturated fatty acids and initiate lipid peroxidation within the cell. So the present study was constructed in order to assess the role of green tea extract (GTE) (300 mg/kg) to overcome the hazards of ionizing radiation. The parameters studied in the current work were serum AST, ALT and ALP activities as well as serum levels of cholesterol, triglyceride, urea and creatinine. Liver and kidney glutathione (GSH), lipid peroxidation (TBARS) and metallothioneins (MTs) contents were also investigated. In addition, contents of some trace elements (Fe, Cu, Zn, Ca, Mg, Se and Mn) in liver, kidney, spleen and testis tissues as well as the content of these trace elements in green tea plant and green tea extract were also estimated. Vitamin E was selected and used at dose of 40 mg/kg as reference standard. Male Wistar albino rats (48) were used, weighing 120-150 g, divided into 6 groups, each consists of 8 rats: Group (1) → received saline for 28 days and served as normal group, Group (2) → received GTE once daily for 28 days, Group (3) → received vitamin E once daily for 28 days, Group 4 → received saline for 21 days then were exposed to 6.5 Gy single dose whole body gamma irradiation followed by receiving saline for 7 days later and served as irradiated control, Group (5) → received GTE once daily for 21 days, and then were exposed to single dose whole body gamma irradiation (6.5 Gy), followed by treatment with GTE 7 days later to be 28 days as group 2 and Group (6) → received vitamin E once daily for 21 days, and then were exposed to single dose whole body gamma irradiation (6.5 Gy), followed by

  14. Radiation protection activities and status in Asia

    Strohal, P.

    1993-01-01

    The status of radiation protection practices in Asian countries is monitored by different means, e.g. the IAEA technical cooperation activities, by an overall assessment of conditions in a country by RAPAT missions, and on the basis of data collected through various regional activities. The radiation protection situation in Asia is very heterogeneous. There is a group of countries with very well developed radiation protection practices and advanced in the application of the Basic Safety Standards, but the majority of Asian member states still need improvement, several lacking the necessary fundamental infrastructure for radiation protection

  15. Active Radiation Shield, Phase I

    National Aeronautics and Space Administration — DEC-Shield technology offers the means to generate electric power from cosmic radiation sources and fuse dissimilar systems and functionality into a structural...

  16. Neutron activation analysis of trace elements in Japanese hormesis cosmetics

    Furuta, E.; Nakahara, H.; Hatsukawa, Y.; Matsue, H.; Sakane, H.

    2008-01-01

    In Japan, cosmetics claiming hormesis effect are available through Internet. Although these cosmetics show the contents, they never mention the minor elements and radioactive sources. The existence of radioisotopes, however, was observed by measurements of the gamma-rays with a HPGe detector. In this study, in order to clarify the contents of trace elements, the hormesis cosmetics including radioactive sources were analyzed using INAA, PGAA and NAA with multiple gamma-ray detection (NAAMG). Nineteen elements were analyzed quantitatively in hormesis cosmetics by INAA, PGAA and NAAMG and 16 elements were detected qualitatively by SEM-EPMA. (author)

  17. Principle of neutron activation analysis and its use for determination of trace elements in sediment

    Verma, Rakesh

    2012-01-01

    Neutron Activation analysis (NAA) is a multi element analysis technique, often non-destructive in nature where approximately 75 elements can be measured with the detection limits ranging from 10 -6 to 10 -12 g of element in a sample. Typical sample sizes range from 1 mg to 1 g, however in principle much larger samples can be activated and the size is only limited by the capacity of the neutron irradiation facility. In NAA, a sample (solid or liquid or gas) is exposed to neutrons and radiations emitted by the radioactive products, formed during the nuclear reaction, are measured using a suitable detector. The energy of the emitted radiation is a characteristic of a radioisotope whereas the intensity of the emitted radiation is proportional to the mass of the analyte. NAA can be carried out by measurement of (i) prompt gamma rays emitted by compound nucleus, called prompt gamma ray NAA (PGNAA) and (ii) β rays emitted from radioactive product or delayed gamma rays emitted subsequent to β decay, called conventional NAA or simply NAA. PGNAA is an online measurement method. PGNAA is complementary to conventional NAA in terms of analyzing low Z elements. Conventional NAA is an offline method and is easy to perform. Depending upon the nature of matrix and analyte to be determined, three approaches are possible in NAA namely, (i) instrumental neutron activation analysis (INAA), (ii) radiochemical neutron activation analysis (RNAA), and (iii) chemical neutron activation analysis (CNAA). Quantification is accomplished by any of the three standardisation methodologies namely (i) absolute method (ii) relative method and (iii) single comparator method. The relative method is most precise and simple to perform. Natural processes responsible for the formation of bottom sediments can be altered by anthropogenic activities. Bottom sediments are a sink as well as a source of contaminants in the aquatic environment. Analysis of-sediments provides environmentally significant

  18. Concentration of 24 Trace Elements in Human Heart Tissue Determined by Neutron Activation Analysis

    Wester, P O

    1964-06-15

    By means of neutron-activation analysis, human heart tissue from autopsy of 20 victims of traumatic accidents has been investigated with respect to the concentration of 24 different trace elements. A recently developed ion-exchange technique combined with gamma spectrometry has been used, which permits simultaneous determination of a large number of trace elements. The following trace elements have been determined quantitatively: Ag, As, Au, Ba, Br; Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Pt, Rb, Sb, Se, Se, Sm, Zn, W. In some heart samples, Hf and Os were determined qualitatively. The mean and standard deviation are given for the elements Cu, Fe, Se and Zn, Since none of the other quantitatively determined trace elements were normally distributed, the median is given as the central value. When possible, comparisons with values from other investigations have been made. No marked differences in the trace-element concentrations with age or sex could be detected.

  19. Concentration of 24 Trace Elements in Human Heart Tissue Determined by Neutron Activation Analysis

    Wester, P.O.

    1964-06-01

    By means of neutron-activation analysis, human heart tissue from autopsy of 20 victims of traumatic accidents has been investigated with respect to the concentration of 24 different trace elements. A recently developed ion-exchange technique combined with gamma spectrometry has been used, which permits simultaneous determination of a large number of trace elements. The following trace elements have been determined quantitatively: Ag, As, Au, Ba, Br; Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Pt, Rb, Sb, Se, Se, Sm, Zn, W. In some heart samples, Hf and Os were determined qualitatively. The mean and standard deviation are given for the elements Cu, Fe, Se and Zn, Since none of the other quantitatively determined trace elements were normally distributed, the median is given as the central value. When possible, comparisons with values from other investigations have been made. No marked differences in the trace-element concentrations with age or sex could be detected

  20. Reduction of Radiation Exposure Using Dynamic Trace Digital Angiography and Spot Fluoroscopy During Adrenal Venous Sampling

    Morita, Satoru; Endo, Kenji; Suzaki, Shingo; Ishizaki, Umiko; Yamazaki, Hiroshi; Nishina, Yu; Sakai, Shuji

    2017-01-01

    PurposeTo compare radiation exposure of adrenal venous sampling (AVS) using dynamic trace digital angiography (DTDA) and spot fluoroscopy with that using conventional methods.Materials and MethodsAVS was performed in 11 patients using DTDA and spot fluoroscopy (Group A) and 11 patients using conventional digital subtraction angiography (DSA) with collimation (Group B). Radiation exposure and image quality of adrenal venography using a five-point scale were compared between the groups.ResultsThe acquisition dose–area product (DAP) using DTDA and fluoro-DAP using spot fluoroscopy in Group A were lower than those using conventional DSA (5.3 ± 3.7 vs. 29.1 ± 20.1 Gy cm"2, p < 0.001) and collimation (33.3 ± 22.9 vs. 59.1 ± 35.7 Gy cm"2, p = 0.088) in Group B. The total DAP in Group A was significantly lower than that in Group B (38.6 ± 25.9 vs. 88.2 ± 53.6 Gy cm"2, p = 0.006). The peak skin dose for patients and operator radiation exposure in Group A were significantly lower than those in Group B (403 ± 340 vs. 771 ± 416 mGy, p = 0.030, and 17.1 ± 14.8 vs. 36.6 ± 21.7 μSv, p = 0.013). The image quality of DTDA (4.4 ± 0.6) was significantly higher than that of digital angiography (3.8 ± 0.9, p = 0.011) and equivalent to that of DSA (4.3 ± 0.8, p = 0.651).ConclusionsRadiation exposure during AVS can be reduced by approximately half for both patients and operators by using DTDA and spot fluoroscopy without sacrificing image quality.

  1. Acceleration of radiative transfer model calculations for the retrieval of trace gases under cloudy conditions

    Efremenko, Dmitry S.; Loyola, Diego G.; Spurr, Robert J.D.; Doicu, Adrian

    2014-01-01

    In the independent pixel approximation (IPA), radiative transfer computations involving cloudy scenes require two separate calls to the radiative transfer model (RTM), one call for a clear sky scenario, the other for an atmosphere containing clouds. In this paper, clouds are considered as an optically homogeneous layer. We present two novel methods for RTM performance enhancement with particular application to trace gas retrievals under cloudy conditions. Both methods are based on reusing results from clear-sky RTM calculations to speed up corresponding calculations for the cloud-filled scenario. The first approach is numerically exact, and has been applied to the discrete-ordinate with matrix exponential (DOME) RTM. Results from the original clear sky computation can be saved in the memory and reused for the non-cloudy layers in the second computation. In addition, for the whole-atmosphere boundary-value approach to the determination of the intensity field, we can exploit a ’telescoping technique’ to reduce the dimensionality (and hence the computational effort for the solution) of the boundary value problem in the absence of Rayleigh scattering contributions for higher azimuthal components of the radiation field. The second approach is (for the cloudy scenario) to generate a spectral correction applied to the radiation field from a fast two-stream RTM. This correction is based on the use of principal-component analysis (PCA) applied to a given window of spectral optical property data, in order to exploit redundancy in the data and confine the number of full-stream multiple scatter computations to the first few EOFs (Empirical Orthogonal Functions) arising from the PCA. This method has been applied to the LIDORT RTM; although the method involves some approximation, it provides accuracy better than 0.2%, and a speed-up factor of approximately 2 compared with two calls of RTM. -- Highlights: • Reusing results from clear-sky computations for a model with a

  2. Reduction of Radiation Exposure Using Dynamic Trace Digital Angiography and Spot Fluoroscopy During Adrenal Venous Sampling

    Morita, Satoru, E-mail: i@imodey.com; Endo, Kenji; Suzaki, Shingo; Ishizaki, Umiko; Yamazaki, Hiroshi; Nishina, Yu; Sakai, Shuji [Tokyo Women’s Medical University Hospital, Department of Diagnostic Imaging and Nuclear Medicine (Radiology) (Japan)

    2017-05-15

    PurposeTo compare radiation exposure of adrenal venous sampling (AVS) using dynamic trace digital angiography (DTDA) and spot fluoroscopy with that using conventional methods.Materials and MethodsAVS was performed in 11 patients using DTDA and spot fluoroscopy (Group A) and 11 patients using conventional digital subtraction angiography (DSA) with collimation (Group B). Radiation exposure and image quality of adrenal venography using a five-point scale were compared between the groups.ResultsThe acquisition dose–area product (DAP) using DTDA and fluoro-DAP using spot fluoroscopy in Group A were lower than those using conventional DSA (5.3 ± 3.7 vs. 29.1 ± 20.1 Gy cm{sup 2}, p < 0.001) and collimation (33.3 ± 22.9 vs. 59.1 ± 35.7 Gy cm{sup 2}, p = 0.088) in Group B. The total DAP in Group A was significantly lower than that in Group B (38.6 ± 25.9 vs. 88.2 ± 53.6 Gy cm{sup 2}, p = 0.006). The peak skin dose for patients and operator radiation exposure in Group A were significantly lower than those in Group B (403 ± 340 vs. 771 ± 416 mGy, p = 0.030, and 17.1 ± 14.8 vs. 36.6 ± 21.7 μSv, p = 0.013). The image quality of DTDA (4.4 ± 0.6) was significantly higher than that of digital angiography (3.8 ± 0.9, p = 0.011) and equivalent to that of DSA (4.3 ± 0.8, p = 0.651).ConclusionsRadiation exposure during AVS can be reduced by approximately half for both patients and operators by using DTDA and spot fluoroscopy without sacrificing image quality.

  3. Retention of 32P activity interfering with the neutron activation analysis of trace elements in biosamples

    Sziklai-Laszlo, I.; Ordogh, M.

    1978-06-01

    Experiments were performed to eliminate the disturbing effect of 32 P when neutron activation analysis is used for the trace element analysis of biological materials. For this reason amorphous zirconium phosphate was selected and prepared by the authors. Retention factors better than 10 2 were obtained using conventional batch techniques. The retention of Cr, Sb, Sc, Zn, Rb, Co and Fe were investigated in nitric acid media, and it was found to be less than 5%. Bowen's kale, dry potato powder and animal bone were analyzed. Some numerical results are given and gamma spectra are shown. (T.G.)

  4. Application of emission CT on nano-robot radiation imaging tracing and isotope sign in nano-robot

    Wang Xuewu; Cheng Jianping; Kang Kejun

    2000-01-01

    Nano-technology has been a scientific and technical frontier with major trends foreseen in several disciplines. Nano-robot is the most remarkable imagination of the application of nano-technology. And it should be concerned of tracing technology along with nano-robot. The character of nano-robot is deeply analyzed, the development status of emission CT is integrated, and the application of emission CT on nano-robot radiation imaging tracing is discussed. The isotope sign of nano-robot is especially calculated and analyzed

  5. Trace elements in precious and common opals using neutron activation analysis

    McOrist, G.D.; Smallwood, A.

    1997-01-01

    Neutron activation analysis (NAA) was used to determine the concentration of trace elements in 44 precious and 52 common opals sampled from a number of recognised fields within Australia. The purpose of this study was to determine if precious and common opals of the same colour and location have the same or a different trace element profile. Similar numbers of black, white and grey samples were studied in each case. In most cases, common opals had a significantly higher concentration of certain trace elements when compared with precious opals. (author)

  6. Trace element evaluation of different varieties of chewing gum by radiochemical neutron activation analysis

    Zaidi, J.H.; Arif, M.; Fatima, I.; Ahmad, S.; Qureshi, I.H.

    2000-01-01

    Extensive use of chewing gums, by children in particular, entails the evaluation of trace element contents in them. Radiochemical neutron activation analysis (RNAA) was successfully employed to determine the concentration of 35 trace elements (essential, toxic and nonessential) in eight different brands of chewing gum generally consumed in Rawalpindi/Islamabad area. Comparison of trace element data of our work with literature has been presented. None of the elements detected in the brands of chewing gum examined was found to be present at a level representing a substantial contribution to the total dietary intake of the element. (author)

  7. Radiation processing activities in the Islamic Republic of Iran: ten years review

    Sohrabpour, M.

    1994-01-01

    The status of radiation technology in the Islamic Republic of Iran with emphasis on research and development activities is reviewed. Gamma Irradiation Centre as the first and pioneering institution of radiation technology in the country during the past few years has placed greater emphasis on research and development work in the areas of radiation effects on polymeric material, microbiology, food Irradiation, radiation physics and dosimetry, trace element analysis, and some engineering design and development projects. An account of the projects in different laboratories, their quality control tasks, cooperation with other institutions as well as recent publications of the Gamma Irradiation Centre (GIC) personnel is presented. (author). 18 refs., 1 fig

  8. Synchrotron radiation and precision mirror metrology with a long trace profiler

    Qian, S.; Takacs, P.Z.

    1997-08-01

    The Long Trace Profiler (LTP) is in use at several synchrotron radiation (SR) laboratories throughout the world and by a number of manufacturers who specialize in making grazing incidence mirrors for SR customers. Recent improvements in the design and operation of the LTP system have reduced the slope profile error bar to the level of 0.3 microradians RMS over measurement lengths of 0.5 meter. This corresponds to a height error bar on the order of 20 nanometers. This level of performance allows one to measure with confidence the shape of large cylinders and spheres that have kilometer radii of curvature in the axial direction. The LTP is versatile enough to make measurements of a mirror in the face up, sideways, and face down configurations. The authors will illustrate the versatility of the current version of the instrument, the LTP II, and present results from two new versions of the instrument: the in-situ LTP (ISLTP) and the Vertical Scan LTP (VSLTP). Both of them are based on the penta-prism LTP (ppLTP) principle with a stationary optical head and moving penta-prism. The ISLTP is designed to measure the distortion of high heat load mirrors during actual operation in SR beam lines. The VSLTP is designed to measure the complete 3-dimensional shape of x-ray telescope cylinder mirrors and mandrels in a vertical configuration. Scans are done both in the axial direction and in the azimuthal direction

  9. Miniature Active Space Radiation Dosimeter, Phase II

    National Aeronautics and Space Administration — Space Micro will extend our Phase I R&D to develop a family of miniature, active space radiation dosimeters/particle counters, with a focus on biological/manned...

  10. JAIF's teacher support activity on radiation education

    Kito, K.; Kudo, K.

    2016-01-01

    Japan Atomic Industrial Forum (JAIF) has been conducting science teacher support activities on radiation education since 2011, after the Fukushima NPP Accident, in cooperation with member organizations of the Japan Nuclear Human Resource Development Network (JN-HRD Net). (author)

  11. Determination of trace gold in rocks and minerals by neutron activation analysis

    Zhao Yunlong; Zhou Suqing; Liang Yutang

    1988-05-01

    The determination of trace gold in rocks and minerals by neutron activation analysis is described. Two methods are used for pre-separating and concentrating the trace gold in geological samples. one of the methods is that the samples are dissolved in aqua regia solution; activated carbon paper pulp filter is used for pre-separating and concentrating trace gold by dynamic adsorption method; then the activated carbon containing gold was ashed at 650 ∼ 700 deg c. The other method is that the samples are dissolved in aqua regia solution; the polyurethane foam plastic filled with activated carbon is used for pre-separating and concentrating trace gold by dynamic adsorption method; then the foam plastic containing gold was ashed at 650 deg c. The gold in ashes is determinated by neutron activation analysis. The detection limit is 0.004ng/g. The accuracy of the method is examined by gold in reference standard material. The results of this method are in good agreement with the recommended value. For analysis of the trace gold by the methods of instrumental neutron activation analysis and epithermal neutron activation analysis, the interference of 411.8 keV γ-ray from 153 Sm, 152 Eu and fission products of uranium and the correction methods are discussed

  12. Molecular requirements for radiation-activated recombination

    Stevens, Craig W.; Zeng Ming; Stamato, Thomas; Cerniglia, George

    1997-01-01

    Purpose/Objective: The major stumbling block to successful gene therapy today is poor gene transfer. We hypothesized that ionizing radiation might activate cellular recombination, and so improve stable gene transfer. We further hypothesized that known DNA-damage-repair proteins might also be important in radiation-activated recombination. Materials and Methods: The effect of irradiation on stable gene transfer efficiency was determined in human (A549 and 39F) and rodent (NIH/3T3) cell lines. Continuous low dose rate and multiple radiation fractions were also tested. Nuclear extracts were made and the effect of irradiation on inter-plasmid recombination/ligation determined. Multiple DNA damage-repair deficient cell lines were tested for radiation-activated recombination. Results: A significant radiation dose-dependent improvement in stable plasmid transfection (by as much as 1300 fold) is demonstrated in neoplastic and primary cells. An improvement in transient plasmid transfection is also seen, with as much as 85% of cells transiently expressing b-galactosidase (20-50 fold improvement). Stable transfection is only improved for linearized or nicked plasmids. Cells have improved gene transfer for at least 96 hours after irradiation. Both fractionated and continuous low dose rate irradiation are effective at improving stable gene transfer in mammalian cells, thus making relatively high radiation dose delivery clinically feasible. Inter-plasmid recombination is radiation dose dependent in nuclear extract assays, and the type of overhang (3', 5' or blunt end) significantly affects recombination efficiency and the type of product. The most common end-joining activity involves filling-in of the overhang followed by blunt end ligation. Adenovirus is a linear, double stranded DNA virus. We demonstrate that adenoviral infection efficiency is increased by irradiation. The duration of transgene expression is lengthened because the virus integrates with high efficiency (∼10

  13. Active learning of neuron morphology for accurate automated tracing of neurites

    Gala, Rohan; Chapeton, Julio; Jitesh, Jayant; Bhavsar, Chintan; Stepanyants, Armen

    2014-01-01

    Automating the process of neurite tracing from light microscopy stacks of images is essential for large-scale or high-throughput quantitative studies of neural circuits. While the general layout of labeled neurites can be captured by many automated tracing algorithms, it is often not possible to differentiate reliably between the processes belonging to different cells. The reason is that some neurites in the stack may appear broken due to imperfect labeling, while others may appear fused due to the limited resolution of optical microscopy. Trained neuroanatomists routinely resolve such topological ambiguities during manual tracing tasks by combining information about distances between branches, branch orientations, intensities, calibers, tortuosities, colors, as well as the presence of spines or boutons. Likewise, to evaluate different topological scenarios automatically, we developed a machine learning approach that combines many of the above mentioned features. A specifically designed confidence measure was used to actively train the algorithm during user-assisted tracing procedure. Active learning significantly reduces the training time and makes it possible to obtain less than 1% generalization error rates by providing few training examples. To evaluate the overall performance of the algorithm a number of image stacks were reconstructed automatically, as well as manually by several trained users, making it possible to compare the automated traces to the baseline inter-user variability. Several geometrical and topological features of the traces were selected for the comparisons. These features include the total trace length, the total numbers of branch and terminal points, the affinity of corresponding traces, and the distances between corresponding branch and terminal points. Our results show that when the density of labeled neurites is sufficiently low, automated traces are not significantly different from manual reconstructions obtained by trained users. PMID

  14. Active learning of neuron morphology for accurate automated tracing of neurites

    Rohan eGala

    2014-05-01

    Full Text Available Automating the process of neurite tracing from light microscopy stacks of images is essential for large-scale or high-throughput quantitative studies of neural circuits. While the general layout of labeled neurites can be captured by many automated tracing algorithms, it is often not possible to differentiate reliably between the processes belonging to different cells. The reason is that some neurites in the stack may appear broken due to imperfect labeling, while others may appear fused due to the limited resolution of optical microscopy. Trained neuroanatomists routinely resolve such topological ambiguities during manual tracing tasks by combining information about distances between branches, branch orientations, intensities, calibers, tortuosities, colors, as well as the presence of spines or boutons. Likewise, to evaluate different topological scenarios automatically, we developed a machine learning approach that combines many of the above mentioned features. A specifically designed confidence measure was used to actively train the algorithm during user-assisted tracing procedure. Active learning significantly reduces the training time and makes it possible to obtain less than 1% generalization error rates by providing few training examples. To evaluate the overall performance of the algorithm a number of image stacks were reconstructed automatically, as well as manually by several trained users, making it possible to compare the automated traces to the baseline inter-user variability. Several geometrical and topological features of the traces were selected for the comparisons. These features include the total trace length, the total numbers of branch and terminal points, the affinity of corresponding traces, and the distances between corresponding branch and terminal points. Our results show that when the density of labeled neurites is sufficiently low, automated traces are not significantly different from manual reconstructions obtained by

  15. Modeling UV Radiation Feedback from Massive Stars. I. Implementation of Adaptive Ray-tracing Method and Tests

    Kim, Jeong-Gyu; Kim, Woong-Tae; Ostriker, Eve C.; Skinner, M. Aaron

    2017-12-01

    We present an implementation of an adaptive ray-tracing (ART) module in the Athena hydrodynamics code that accurately and efficiently handles the radiative transfer involving multiple point sources on a three-dimensional Cartesian grid. We adopt a recently proposed parallel algorithm that uses nonblocking, asynchronous MPI communications to accelerate transport of rays across the computational domain. We validate our implementation through several standard test problems, including the propagation of radiation in vacuum and the expansions of various types of H II regions. Additionally, scaling tests show that the cost of a full ray trace per source remains comparable to that of the hydrodynamics update on up to ∼ {10}3 processors. To demonstrate application of our ART implementation, we perform a simulation of star cluster formation in a marginally bound, turbulent cloud, finding that its star formation efficiency is 12% when both radiation pressure forces and photoionization by UV radiation are treated. We directly compare the radiation forces computed from the ART scheme with those from the M 1 closure relation. Although the ART and M 1 schemes yield similar results on large scales, the latter is unable to resolve the radiation field accurately near individual point sources.

  16. Trace element determination in beauty products by k0-instrumental neutron activation analysis

    Sneyers, L.; Verheyen, L.; Vermaercke, P.; Bruggeman, M.

    2009-01-01

    A recent study on trace elements in beauty products and cosmetics sold on the Asian market has shown the presence of high levels of U, Th and rare earth elements in so called 'Hormesis cosmetics'. For the purpose of comparison, some more information about trace elements in European cosmetics would be useful. In this paper the results obtained using k 0 -standardised Instrumental Neutron Activation Analysis (k 0 -INAA) for more than 20 trace elements in 20 different beauty products collected from the European market are presented. We found traces of Ba, As and Sb which is in breach with European legislation. For some of the other elements like Cr and Co further speciation is needed in order to evaluate their presence in beauty products. (author)

  17. Activation analysis of trace metals in several kinds of tissues of even-toed ungulates

    Fukushima, M.; Tamate, H.; Sato, S.; Terui, S.; Mitsugashira, T.

    1999-01-01

    The normal concentration levels of trace metals in several kinds of tissues of even-toed ungulates have been determined by instrumental neutron activation analysis, photon activation analysis, and flame atomic absorption spectrometry. In the present work the concentrations of 13 elements (Ag, Br, Ca, Co, Cu, Fe, Mg, Mn, Mo, Na, Rb, Se, and Zn) were analyzed. (author)

  18. Storage and pre-neutron-activation-analysis treatment for trace-element analysis in urine

    Blotcky, A.J.; Rack, E.P.

    1985-01-01

    The problems regarding storage and pre-neutron-activation-analysis treatment for the elements aluminum, calcium, vanadium, selenium, copper, iodine, zinc, manganese, and magnesium in a urine matrix are reviewed. The type of collection and storage procedure and pre-neutron activation analysis treatment of urine depend on the specific trace element; that is, its inherent physical and chemical properties. Specifically polyethylene in teflon containers are the most suitable for general determinations. Whether any preservative is added would depend upon the stability of the trace element and its tendency for surface adsorption. Preferably, preservatives should contain no radioactivatable elements for maximum efficacy. Freeze drying or packing urine shipments under dry ice needs to be explored on an individual basis. Each pre- or post-neutron activation analysis treatment is specific and optimized for the trace element analyzed

  19. Activities of Moroccan Radiation Protection Association

    Choukri, A.

    2010-01-01

    Encourage activities and information exchange in the field of radiation protection and related areas; Assist in informing both the public and the professionals on the problems and requirements related to radiation protection for the protection of man and the environment; Promote professional training in radiation protection. The use of nuclear technology in medicine, agriculture and industry is very advanced in Morocco. This technological progress has been accompanied by fairly detailed legislation and significant involvement on the part of Morocco in international conventions and agreements

  20. Design of an electrochemically assisted radiation sensor for α-spectrometry of actinides traces in water

    Sanoit, Jacques de; Quang Tran, Thuan; Pomorski, Michal; Pierre, Sylvie; Mer-Calfati, Christine; Bergonzo, Philippe

    2013-01-01

    We describe a new approach for the detection and identification of actinides at low activity levels directly in aqueous solution. The measurement consists initially, in immobilizing alpha emitters in the form of insoluble hydroxides onto the entrance window of an immersed alpha particles detector. For this, a boron doped diamond detector window is negatively polarized to produce a basic layer on its surface by water decomposition. Actinides elements that are known to be very sensitive to hydrolysis are precipitated as solid hydroxides onto the entrance window of the sensor. Due to the absence of an air layer between the radioactive source and the detector, there is no need for vacuum during the alpha spectrometry measurement. After analysis, the detector can be easily cleaned by anodization in the aqueous medium to be reused at once. The minimum detectable activity concentration (MDA) of the system has been evaluated with 241 Am at 0.5 Bq/L for a 0.33 cm 2 area Si PIN diode. - Highlights: • The method allows to find trace of actinides in water. • The method allows direct α spectrometry of actinides in aqueous solutions. • Alpha spectrometry is performed without the use of a vacuum chamber. • Decontamination of the sensor before re-use is very fast and efficient. • Detection limit is lowered by concentration of actinides at the detector entrance window

  1. Analysis of traces at ORNL's new high-flux neutron activation laboratory

    Ricci, E.; Handley, T.H.; Dyer, F.F.

    1974-01-01

    The investigations are outlined, which are carried out in order to develop (preferably instrumental) methods for multielement analysis of various trace elements. For this reason a new High-Flux NAA Laboratory was constructed at ORNL's. A general review is given on the Laboratory, further some methods and applications are shown. In the field of comparator activation analysis comparative data are given on mercury determinations in various matrices, and on arsenic determination in grasshoppers. This later method was used to trace the transport of arsenic containing pesticides. Some data are given on absolute activation analysis of Na, Ci, Mn, Br, and Au, too. (K.A.)

  2. Cooling Active Region Loops Observed With SXT and TRACE

    Winebarger, Amy R.; Warren, Harry P.

    2005-01-01

    An Impulsive Heating Multiple Strand (IHMS) Model is able to reproduce the observational characteristics of EUV (~ 1 MK) active region loops. This model implies that some of the loops must reach temperatures where X-ray filters are sensitive (> 2.5 MK) before they cool to EUV temperatures. Hence, some bright EUV loops must be preceded by bright X-ray loops. Previous analysis of X-ray and EUV active region observations, however, have concluded that EUV loops are not preceded by X-ray loops. In...

  3. Trace element analysis of common salt using neutron activation analysis

    Usman, K.

    1993-01-01

    Instrumental Fast Neutron Activation Analysis (IFNAA) technique has been used in the qualitative and quantitative determination of the impurity elements in common salt. Samples of the different types of common salt processed in Nigeria and some of those imported into the country were used. The type A711 KAMAN neutron generator and a high-purity Germanium (HpGe) gamma spectrometer available at the Centre for Energy Research and Training, Ahmadu Bello University, Zaria has been used. The ORTEC ADCAM 100 Emulation Software (Maestro) was used in the qualitative measurement of the detected elements. The G.R.G Activation Analysis System by G. R. Gilmore, 1987, was used in the quantitative determination of the elements detected by relative method. Aluminium and arsenic were detected and measured

  4. Instrumental neutron activation analysis in environmental studies of trace elements

    Salmon, L.

    1975-06-01

    The application of a routine instrumental nuclear method is described in relation to environmental surveys and studies. A working rather than formal review is made of the techniques applied with particular reference to the data processing methods involved. The elements measured by instrumental activation analysis were: Ag, Al, As, Au, Ba, Br, Ca, Ce, Cl, Cd, Co, Cr, Cs, Cu, Fe, Hg, I, In, La, Mn, Na, Ni, Pb, Rb, Sb, Sc, Se, Th, Ti, U, V, W, Zn. (author)

  5. Natural radiation exposure modified by human activities

    Fujimoto, Kenzo

    1995-01-01

    We are now living in the radiation environment modified by our technology. It is usually called 'Technologically Enhanced Natural Radiation' and have been discussed in the UNSCEAR Reports as an important source of exposure. The terrestrial radionuclide concentrations as well as the intensity of cosmic rays are considered to have been constant after our ancestors came down from trees and started walking on their two feet. However, we have been changing our environment to be more comfortable for our life and consequently ambient radiation levels are nomore what used to be. In this paper exposures due to natural radiation modified by our following activities are discussed: housing, balneology, cave excursion, mountain climbing, skiing, swimming, smoking and usage of mineral water, well water, coal, natural gas, phosphate rocks and minerals. In the ICRP Publication No. 39, it is clearly mentioned that even natural radiation should be controlled as far as it is controllable. We have to pay more attention to our activities not to enhance the exposure due to unnecessary, avoidable radiation. (author)

  6. Radiation Education Activities | RadTown USA | | US EPA

    2018-03-12

    EPA's Radiation Education Activities are designed to help increase awareness and understanding of radiation concepts among middle and high school students. The activities introduce basic concepts of radiation, non-ionizing and ionizing radiation, radiation protection, radioactive atoms and radioactive decay.

  7. Trace elements determination in tungsten ores by neutron activation analysis

    Mireles Garcia, F.

    1991-01-01

    The kinetics approach of the leaching of industrial scheelite (CaWO 4 ) concentrates in hydrochloric acid media investigated under controlled acid concentration in leachates, reaction atmospheres and temperature conditions. Experiments show that the scheelite decomposition rate increases as the acid concentration in the leaching solution and temperature increase. The apparent activation energy for the scheelite acid decomposition process is estimated in the present study to be equal to 10.43 Kcal(mol) -1 . On the basis of the experimental results, it is proposed an equilibria competition mechanism as a function of the acid concentration which explains the peculiar behavior of the experimental systems at low temperatures. (Author)

  8. The use of synchrotron radiation for trace element analysis and element mapping by scanning X-ray fluorescence

    Davies, S.T.

    1983-01-01

    Synchrotron Radiation excited X-Ray Fluorescence is a potentially powerful tool for the routine quantitative chemical analysis of materials, with minimum detection limits typically of the order of a tenth of a ppm, and with the added advantages of simultaneous multi-element detection capability, spatial resolution on a micron scale, large signal to noise ratios and short analysis times. This paper presents a brief review of the use of Synchrotron Radiation in Trace Element Analysis and discusses the requirements for a microprobe for chemical analysis utilising SR. Data obtained at the Synchrotron Radiation Source, Daresbury Laboratory include XRF spectra of standard reference materials and an application of the technique to the study of ion implanted layers in semiconductors is outlined. (author)

  9. An Angiotensin II type 1 receptor activation switch patch revealed through Evolutionary Trace analysis

    Bonde, Marie Mi; Yao, Rong; Ma, Jian-Nong

    2010-01-01

    to be completely resolved. Evolutionary Trace (ET) analysis is a computational method, which identifies clusters of functionally important residues by integrating information on evolutionary important residue variations with receptor structure. Combined with known mutational data, ET predicted a patch of residues......) displayed phenotypes associated with changed activation state, such as increased agonist affinity or basal activity, promiscuous activation, or constitutive internalization highlighting the importance of testing different signaling pathways. We conclude that this evolutionary important patch mediates...

  10. The role of high-energy synchrotron radiation in biomedical trace element research

    Pounds, J.G.; Long, G.J.; Kwiatek, W.M.; Jones, K.W.; Gordon, B.M.; Hanson, A.L.

    1987-01-01

    This paper will present the results of an investigation of the distribution of essential elements in the normal hepatic lobule. the liver is the organ responsible for metabolism and storage of most trace elements. Although parenchymal hepatocytes are rather uniform histologically, morphometry, histochemistry, immunohistochemistry, and microdissection with microchemical investigations have revealed marked heterogeneity on a functional and biochemical level. Hepatocytes from the periportal and perivenous zones of the liver parrenchyma differ in oxidative energy metabolism, glucose uptake and output, unreagenesis, biotransformation, bile acid secretion, and palsma protein synthesis and secretion. Although trace elements are intimately involved in the regulation and maintenance of these functions, little is known regarding the heterogeneity of trace element localization of the liver parenchyma. Histochemical techniques for trace elements generally give high spatial resolution, but lack specificity and stoichiometry. Microdissection has been of marginal usefulness for trace element analyses due to the very small size of the dissected parenchyma. The characteristics of the high-energy x-ray microscope provide an effective approach for elucidating the trace element content of these small biological structures or regions. 5 refs., 1 fig., 1 tab

  11. Trace elements in Turkish tobacco determined by instrumental neutron activation analysis

    Guelovali, M.C.; Guenduez, G.

    1983-01-01

    The concentration of 20 trace elements in nine brands of Turkish cigarette tobacco and in a brand of pipe tobacco ash has been determined by instrumental neutron activation analysis. The percent transference of elements into smoke has been estimated from the amounts remaining in the ash. (author)

  12. Active fault traces along Bhuj Fault and Katrol Hill Fault, and ...

    face, passing through the alluvial-colluvial fan at location 2. The gentle warping of the surface was completely modified because of severe cultivation practice. Therefore, it was difficult to confirm it in field. To the south ... scarp has been modified by present day farming. At location 5 near Wandhay village, an active fault trace ...

  13. Application of neutron activation analysis to trace elements determinations in lung samples

    Rogero, S.O.

    1991-01-01

    The purpose of this work was to apply the instrumental neutron activation analysis method to determine trace elements in lung samples from smokers and non smokers. Samples of lung tissues and lymph nodes from pulmonary hilum analyzed were collected from autopsies by researchers from Faculdade de Medicina da USP. (author)

  14. Trace element concentrations in human bone using instrumental neutron activation analysis

    El-Amri, F.A.; El-Kabroun, M.A.R.

    1997-01-01

    Instrumental neutron activation analysis has been applied to analyze 23 bone samples obtained from Libyan patient aged (3-80) years for the study of the concentration levels of trace elements Ba, Br, Ca, Fe, Sr and Zn and their concentration patterns regarding to the age and sex of the patients. (author)

  15. Trace elements monitored with neutron activation analysis durig neurodegeneration in brains of mutant mice

    Kranda, Karel; Kučera, Jan; Bäurle, J.

    2006-01-01

    Roč. 269, č. 3 (2006), s. 555-559 ISSN 0236-5731 Institutional research plan: CEZ:AV0Z10480505 Keywords : trace elements * neutron activation analysis * brain neurodegeneration * mutant mice Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 0.509, year: 2006

  16. Characterization of elements in trace amounts in imperial topaz through neutron activation analysis

    Oliveira, Ester Figueiredo de; Sabioni, Antonio C. S.; Ferreira, Cesar M.

    2000-01-01

    This work deals with the mineral characterization of the elements in trace amounts of imperial topaz, original form Mina Capao da Lama, Ouro Preto, MG, Brazil, through the neutron activation analysis. Recent results have permitted to quantify Cr, Cs, Mn, Na, Ga, Sb and Au. The main goal of this study is the contribution to the mineral and gemological research of the imperial topaz

  17. Determination of trace elements in biological material by neutron activation analysis

    Tran Van, L.; Teherani, D.K.

    1989-01-01

    Eighteen trace elements in biological materials [grass (Imperata cylindrica), mimosa plant (Mimosa pudica), rice] by neutron activation method were determined. In the comparative analysis the content of the same element was different in each material, although they were collected at the same place and the same sampling method was applied. (author) 4 refs.; 1 fig.; 1 tab

  18. Polarization ray tracing in anisotropic optically active media. II. Theory and physics

    McClain, S.C.; Hillman, L.W.; Chipman, R.A.

    1993-01-01

    Refraction, reflection, and amplitude relations are derived that apply to polarization ray tracing in anisotropic, optically active media such as quartz. The constitutive relations for quartz are discussed. The refractive indices and polarization states associated with the two modes of propagation are derived as a function of wave direction. A procedure for refracting at any uniaxial or optically active interface is derived that computes both the ray direction and the wave direction. A method for computing the optical path length is given, and Fresnel transmission and ref lection equations are derived from boundary conditions on the electromagnetic fields. These ray-tracing formulas apply to uniaxial, optically active media and therefore encompass uniaxial, non-optically active materials and isotropic, optically active materials

  19. Essential trace elements in edible mushrooms by Neutron Activation Analysis

    Moura, Patricia L.C.; Maihara, Vera A.; Castro, Lilian P. de [Instituto de Pesquisa e Energetica e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: patricialandim@ig.com.br; vmaihara@ipen.br; lilian.Pavanelli@terra.com.br; Figueira, Rubens C.L. [Universidade Cruzeiro do Sul, Sao Paulo, SP (Brazil)]. E-mail: figueiraru@yahoo.com.br

    2007-07-01

    Mushrooms are excellent nutritional sources since they provide proteins, fibers and mineral, such as K, P, Fe. They have also been the focus of medical research. In Brazil mushrooms are not consumed in large quantities by the general population since people know little about the nutritional and medicinal benefits that mushrooms offer. Hence, this study intends to contribute to a better understanding of the essential element content in edible mushrooms, which are currently commercialized in Sao Paulo state. Br Fe, K, Na and Zn concentrations were determined by Instrumental Neutron Activation Analysis in the following mushroom species: Shitake (Lentinus edodes), Shimeji (Pleurotus ssp), Paris Champignon (Agaricus bisporus), Hiratake ( Pleurotus ssp) and Eringue (Pleurotus Eryngu. The mushroom samples were acquired from commercial establishments in the city of Sao Paulo and directly from the producers. Essential element contents in mushrooms varied between Br 0.03 to 4.1 mg/kg; Fe 20 to 267 mg/kg; K 1.2 to 5.3 g/kg, Na 10 to 582 mg/kg and Zn 60 to 120 mg/kg. The results confirm that mushrooms can be considered a good source of K, Fe and Zn. The low Na level is a good nutritional benefit for the consumer. (author)

  20. Trace elements evaluation of some medicinal herbs by instrumental neutron activation analysis

    Zaidi, J.H.; Fatima, I.; Qureshi, I.H.; Subhani, M.S.

    2004-01-01

    Instrumental neutron activation analysis has been used for the analysis of seven varieties of medicinal herbs generally used by the people of South Asian region. Twenty-one trace elements (essential, toxic and non-essential) were determined. This data should not only be helpful in establishing the base-line values in these medicinal herbs but also in correlating their role as therapeutic agents. A comparison of our data with literature values shows variation in trace element contents of same species of different origin which can be attributed to ecological and geographical variations to some extent; however an exact interpretation demands further extensive investigations. (orig.)

  1. Evaluation of Forensic DNA Traces When Propositions of Interest Relate to Activities

    Biedermann, Alex; Champod, Christophe; Jackson, Graham

    2016-01-01

    When forensic scientists evaluate and report on the probative strength of single DNA traces, they commonly rely on only one number, expressing the rarity of the DNA profile in the population of interest. This is so because the focus is on propositions regarding the source of the recovered trace...... demonstrated in day-to-day forensic practice and is also voiced in specialized literature. Yet many forensic scientists remain reluctant to assess their results given propositions that relate to different activities. Some scientists consider evaluations beyond the issue of source as being overly speculative...

  2. Trace element analysis of human blood serum by neutron activation analysis

    Nakahara, H.; Nagame, Y.; Yoshizawa, Y.; Oda, H.; Gotoh, S.; Murakami, Y.

    1979-01-01

    An attempt was made to determine if there is any correlation between trace element concentrations in human blood serum and some specific diseases. The serum samples of the patients suffering from cancer, Down syndrome, and Banti syndrome were analyzed by the neutron activation method and compared with the trace element concentrations observed among clinically healthy men. The cancer patients had concentrations in Rb, Mn, Fe, Co, Cu, Zn, Al and Se below normal. The Down syndrome patients were found to have similar deficiencies in Cr, Mn, Fe, Co, Zn, Cu and Sb. (author)

  3. Neutron activation studies of trace elements in tree rings

    Tout, R.E.; Gilboy, W.B.; Spyrou, N.M.

    1977-01-01

    The levels of twelve elements most of which are either considered essential to plant growth or have been detected in air filter samples in an air pollution survey have been monitored in three transverse sections of trees, two elms (ring-porous trees) and one cedar (a conifer). An irradiation time of 10 minutes and a waiting time of 1 minute were selected followed by a 10-minute count. The activated samples were placed on a specially shaped perspex disc situated on a 45-cm 3 Ge(Li) detector. The gamma-ray spectra were subsequently analysed on a 6600 computer, using the library program 'SAMPO' to which subroutines have been added for peak identification and for calculating the mass of elements present. All irradiations were carried out using a thermal neutron flux of 1.5x10 12 ncm -2 sec -1 . Two dimensional distributions of the elements around the tree rings of the section and radially from ring to ring, have been obtained to see if tree rings can be analysed for use as a record of historical pollution. Definite movement of most of these elements between the two main parts of the xylem has occured in all three trees. This makes it seem unlikely that any pollution products taken up from the atmosphere would be retained in the same ring in which they were originally accumulated. Exceptions may occur in the sapwood rings, where a few elements, especially Cl, show directional peaks which do not persist in the heartwood. (T.G.)

  4. Determination of trace elements in cigarette and tobacco by neutron activation analysis

    Nouchpramool, S.

    1988-01-01

    The objective of this work is to determine the concentration of 22 trace elements in cigarette and tobacco by instrumental neutron activation analysis in which multielements can be analyzed simultaneously with high sensitivity and reliability as well as easy and rapid. It is well known that, trace toxic elements with high concentration may be harmful for health of smokers. Since they might damage the respiratory system and might cause other diseases. The finding for this report can be used as the basis of further study on toxic of trace elements to the smoker. The results of this analysis show that the bromine content in all samples is significantly high, but the concentration of the other elements are varying from one to another. Bromine concentration might come from soil and/or smoked tobacco leaves with methyl bromide as fungicide

  5. Determination of trace impurities in iron-based alloy using neutron activation analysis

    Zaidi, J.H.; Waheed, S.; Ahmad, S.

    2000-01-01

    A radiochemical neutron activation analysis procedure has been developed and applied to investigate 40 major, minor, and trace impurities in iron-based alloy. A comparison of RNAA and INAA indicated a significant improvement in the detection limits. The extensive use of these alloys in the heavy mechanical industry, manufacturing of aircraft engines, nuclear applications, medical devices and chemical equipment requires their precise characterization. The concentration of iron in the iron-based alloy was found to be 86.7%, whereas Ca, Cr, K, Mg, Mn, V and W were the other constituents of the alloy, which constituted to around 12.89%. The rest of the elements were present in minor or trace levels. Most of the rare earth elements were also present in trace amounts. (orig.)

  6. The role of neutron activation analysis for trace elements characterization, analysis and certification in atmospheric particulates

    Rizzio, Enrico; Gallorini, Mario

    2002-01-01

    The Neutron Activation Analysis (NAA) owns these requirements and is universally accepted as one of the most reliable analytical tools for trace and ultratrace elements determination. Its use in trace elements atmospheric pollution related studies has been and is still extensive as can be demonstrate by several specific works and detailed reviews. In this work, the application of this nuclear technique, in solving a series of different analytical problems related to trace elements in air pollution processes is reported. Examples and results are given on the following topics: characterization of urban and rural airborne particulate samples; particles size distribution in the different inhalable and respirable fractions (PM10 and PM 2.5); certification of related Standard Reference Materials for data quality assurance. (author)

  7. Model of heat transfer by radiation in a pool of spent fuel by TRACE; Modelo de transmision de calor por radiacion en una piscina de combustible gastado mediante TRACE

    Sanchez-Saez, F.; Carlos Alberola, S.; Martorell Alsina, J. J.; Villanueva Lopez, J. F.

    2013-07-01

    The work involves the simulation thermal-hydraulic of a spent fuel pool to cause a transient loss of coolant with coolant loss through the transfer channel. The simulation performed with the Best Estimate TRACE code. To follow the evolution of behavior of the pool, a variable is important to follow the sheath temperature, whose evolution depends on the heat that gets broadcast. In this simulation was considered the transfer by convection and has been compared with the evolution of Variable considering convection plus radiation. The proposed radiation pattern RADGEN obtains code data for use in TRACE. With this model, obtains an evolution of the temperature in the transient pod less conservative.

  8. Evaluation of Circle Diameter by Distributed Tactile Information in Active Tracing

    Hiroyuki Nakamoto

    2013-01-01

    Full Text Available Active touch with voluntary movement on the surface of an object is important for human to obtain the local and detailed features on it. In addition, the active touch is considered to enhance the human spatial resolution. In order to improve dexterity performance of multifinger robotic hands, it is necessary to study an active touch method for robotic hands. In this paper, first, we define four requirements of a tactile sensor for active touch and design a distributed tactile sensor model, which can measure a distribution of compressive deformation. Second, we suggest a measurement process with the sensor model, a synthesis method of distributed deformations. In the experiments, a five-finger robotic hand with tactile sensors traces on the surface of cylindrical objects and evaluates the diameters. We confirm that the hand can obtain more information of the diameters by tracing the finger.

  9. Prompt radiation activation analysis, (1) Theoretical study

    EL Barouni, A. M.; Araddad, S. Y.; Mosbah, D. S.; Elfakhri, S. M.; Rateb, J. M.; Benghzail, M. A.

    2004-01-01

    The measurement of the prompt γ following neutron capture in the reaction has been extensively developed. In this method the gamma-ray intensity is depended only upon the radiative capture cross-section and not upon the half-life of the product nucleus. The prompt gamma-ray activation analysis method stems from the radiative capture process which results in the decay of the compound nucleus by the emission of characteristic gamma radiation, either as a single photon with kinetic energy equal to the excitation energy less the recoil energy or, more likely, by a cascade of two or more photons with the same energy. The equations and the computer program required to calculate the yield, the intensity and the K χ emission probability per disintegration, are given in this study.(author)

  10. Mapping of trace elements with photon microprobes: x-ray fluorescence with focussed synchrotron radiation

    Hanson, A.L.; Jones, K.W.; Gordon, B.M.; Pounds, J.G.; Rivers, M.L.; Schidlovsky, G.

    1985-04-01

    High energy electron synchrotron storage rings provide copious quantities of polarized photons that make possible the mapping of many trace elements with sensitivities at the parts per billion (ppB) level with spatial resolutions in the micrometer range. The brightness of the x-ray ring of the National Synchrotron Light Source (NSLS), presently being commissioned, will be five orders of magnitude larger than that of the bremsstrahlung spectrum of state-of-the-art rotating anode tubes. We will discuss mapping trace elements with a photon microprobe presently being constructed for use at the NSLS. This microprobe will have micrometer spatial resolution

  11. Radiation characteristics of water droplets in a fire-inspired environment: A Monte Carlo ray tracing study

    Wu, Bifen; Zhao, Xinyu

    2018-06-01

    The effects of radiation of water mists in a fire-inspired environment are numerically investigated for different complexities of radiative media in a three-dimensional cubic enclosure. A Monte Carlo ray tracing (MCRT) method is employed to solve the radiative transfer equation (RTE). The anisotropic scattering behaviors of water mists are modeled by a combination of the Mie theory and the Henyey-Greestein relation. A tabulation method considering the size and wavelength dependencies is established for water droplets, to reduce the computational cost associated with the evaluation of the nongray spectral properties of water mists. Validation and verification of the coupled MCRT solver are performed using a one-dimensional slab with gray gas in comparison with the analytical solutions. Parametric studies are then performed using a three-dimensional cubic box to examine radiation of two monodispersed and one polydispersed water mist systems. The tabulation method can reduce the computational cost by a factor of one hundred. Results obtained without any scattering model better conform with results obtained from the anisotropic model than the isotropic scattering model, when a highly directional emissive source is applied. For isotropic emissive sources, isotropic and anisotropic scattering models predict comparable results. The addition of different volume fractions of soot shows that soot may have a negative impact on the effectiveness of water mists in absorbing radiation when its volume fraction exceeds certain threshold.

  12. Determination of Gold Traces in 4th Century B.C. Silver Coins By Neutron Activation Analysis

    Ronen, Y.; Kubani, G.

    2004-01-01

    A method based on non-destructive neutron activation analysis was developed for measuring traces of gold in silver. This method requires a very small neutron source and, in this study, it was Am-Be of 5μCi. With a small neutron source, the equipment is not expensive and radiation protection problems are reduced. Our method was applied to ancient silver coins from the 4th-3rd centuries B.C. These coins were obols minted in Gaza and Yehud coins minted in Jerusalem. It was found that there is gold in all of them. Their relative gold content was found to be between 7*10 -3 and 8.9*10 - 3 with a relative accuracy of less than 7%. The gold content in silver coins can serve as a ''finger prints' for the origin of the silver

  13. The Determination Of Trace Element Levels In Diet By Neutron Activation Analysis

    Kukuh, Ratnawati; Djojosubroto, Harjoto

    2002-01-01

    Trace element levels in foodstuff are normally low. Although the levels are low, certain trace elements which are called essential trace elements have an important role in metabolism process. Deficiency or intoxication of essential trace elements may lead to abnormal health. In this study the levels of Zn, Fe, AI, Mn, and Co in diet samples were determined by neutron activation analysis, and then the daily intakes of these elements were estimated. The samples were prepared by duplicate diet method, representing those that were consumed by population from West, Central and East Java. Following the collection the respective samples were blended, then were freeze dried at-54 o c. The elemental quantification were performed by neutron activation analysis. The traceability of the determination was ensured using standard reference material NIST-SRM-1548a. The results show that the daily intake for Zn were 2.8-22.8 mg/day (reference value were 5- 40 mg/day), Fe were 3.1-26.5 mg/day (reference value were 6-40 mg/day), AI were 4,2-32.9 mg/day (reference value were 2-45 mg/day), Mn were 1.0-5,6 mg/day (reference value were 0.4-10,0 mg/day), and Co were 0,005-0,074 mg/day (reference value were 0.005 -1.8 mg/day

  14. Application of the neutron activation analysis method for determing trace elements in Brazilian food sample

    Maihara, V.A.; Vasconcellos, M.B.A.

    1988-01-01

    Recently there has been an increase of consciousness about the importance of trace elements in human health and disease as well as rising concern about food contamination. The development of sensitive, accurate and price methods is one of the most important of the knowledge of trace elements contents in foods and in biological samples. Neutron activation analysis is one of the most suitable tecniques because a great number of elements can be determined in concentrations in the range of μg/g to ng/g. The present work is a part of an AIEA Co-ordinated Research Programme on the applications of nuclear techniques for toxic elements in foodstuffs. Neutron activation analysis is applied to analysis of bread, milk powder and rice that are considered essential foods in the Brazilian diet. Some aspects of the activation analysis of biological matrices are discussed. (author) [pt

  15. Trace elements in high purity materials for advanced technology: contribution of neutron activation analysis and radioanalytical technique

    Gallorini, M.; Pietra, R.; Sabbioni, E.

    1991-01-01

    Neutron activation analysis and radioanalytical techniques have been employed to investigate problems related to trace elements and high purity technology materials. Applications of these techniques are overviewed: semiconductor technology as in the case of As and In ion implantation in high purity silicon; problems related to trace elements impurities in thermometric measurements; coating materials to prevent trace elements contamination in biological sampling and metals release from human prostheses. (author) 8 refs.; 2 figs.; 8 tabs

  16. Determination of trace elements in BCR single cell protein via destructive neutron activation analyses

    Tjioe, P.S.; Goeij, J.J.M. de; Nooijen, J.L.; Kroon, J.J.

    1978-10-01

    The amount of some trace elements in single cell protein (SCP), a product of BP Research Centre at Sunbury-at-Thames, England, was determined by neutron activation analysis. The SCP-samples were irradiated in the reactor of the Interuniversity Reactor Institute at Delft in a neutron flux of 1.0x10 13 n/cm 2 s for 12 hours. Samples of Bowen's Kale were used as reference material. After a decay of two or three days the samples were chemically destroyed, and the trace elements were separated. The quantity of the following elements was determined by measuring the γ-activity by means of a scintillation counter: antimony, cadmium, mercury, arsenic and selenium. The amounts of these elements in the SCP and in the reference material were tabled

  17. Study of the source term of radiation of the CDTN GE-PET trace 8 cyclotron with the MCNPX code

    Benavente C, J. A.; Lacerda, M. A. S.; Fonseca, T. C. F.; Da Silva, T. A. [Centro de Desenvolvimento da Tecnologia Nuclear / CNEN, Av. Pte. Antonio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais (Brazil); Vega C, H. R., E-mail: jhonnybenavente@gmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

    2015-10-15

    Full text: The knowledge of the neutron spectra in a PET cyclotron is important for the optimization of radiation protection of the workers and individuals of the public. The main objective of this work is to study the source term of radiation of the GE-PET trace 8 cyclotron of the Development Center of Nuclear Technology (CDTN/CNEN) using computer simulation by the Monte Carlo method. The MCNPX version 2.7 code was used to calculate the flux of neutrons produced from the interaction of the primary proton beam with the target body and other cyclotron components, during 18F production. The estimate of the source term and the corresponding radiation field was performed from the bombardment of a H{sub 2}{sup 18}O target with protons of 75 μA current and 16.5 MeV of energy. The values of the simulated fluxes were compared with those reported by the accelerator manufacturer (GE Health care Company). Results showed that the fluxes estimated with the MCNPX codes were about 70% lower than the reported by the manufacturer. The mean energies of the neutrons were also different of that reported by GE Health Care. It is recommended to investigate other cross sections data and the use of physical models of the code itself for a complete characterization of the source term of radiation. (Author)

  18. Synchrotron radiation TXRF and EDXRS on AP1 foils applied to the analysis of trace elements in metal alloys: a comparison

    Wobrauschek, P.; Pepponi, G.; Streli, C.; Zoeger, N.; Jokubonis, C.; Hegedues, F.; Falkenberg, G.

    2000-01-01

    Synchrotron radiation induced TXRF and conventional 45 o EDXRF using a film 150 nm thick have been exploited for the elemental analysis of traces in alloys used for the construction of reactor pressure vessels of nuclear power plants. The methods used achieve a very low background due to the total reflection phenomenon and the thin sample support. Synchrotron radiation was needed since there are no laboratory sources which can deliver a collimated beam of the energy needed to excite the K-shell of the Rare Earth Elements, allowing the achievement of minimum detection limits relevant for the proposed purpose (pg/g range). Moreover the linear polarization of synchrotron radiation combined with a side-looking detection manages to reduce the scattering due to the remaining matrix contained in the analyzed samples. Lowest detection limits for Nb and for some of the rare earth elements obtained with the two techniques are presented and the two approaches compared. Experiments have been carried out at Hasylab beamline L (bending magnet). For the TXRF experiments the beamline was equipped with a double reflector collimator, which acts as a collimator also as a high energy cut-off, and a multilayer for the monochromatization of the beam. For the measurements in the standard 45 o geometry the microfluorescence facility installed at the beamline was used. Chemical preparation of the sample included dissolution and separation by means of ionic exchange chromatography. Detection of traces of Niobium allows a retrospective fast neutron flux determination on nuclear reactor pressure vessels. Thus an indirect monitoring of the status of the vessel can be done analyzing small quantities of steel taken from the inner surface of the pressure vessel. Both the techniques are well suited to the analysis since they require a low amount of sample, important on one hand because of the limited disposal and on the other because of its high specific activity. Of interest is also the

  19. Swedish Radiation Protection Institute: information activities

    Persson, Lars

    2000-01-01

    The purpose of SSI's Information and PR Service is to broaden public awareness of radiation and radiation risks as well as to fulfill other performance goals. SSI achieves this through its advisory, educational and informative activities. SSI publishes two external magazines, Stralskyddsnytt and SSI News. Stralskyddsnytt - which is available in Swedish only - has a circulation of 2,000 and is published four times a year. SSI News - which is in English - is published twice a year and has a circulation of about 1,800. Another important channel of communication is the web site (www.ssi.se). Taking advantage of PUSH technology, SSI also distributes, by e-mail, press releases and other important information on radiation to radiation protection professionals in Sweden. SSI continuously monitors news by subscribing to a press clipping service. SSI Training is a commercial unit within the Information and PR Service. A policy for mass media contacts exists as well as a policy for internal communication. SSI has a graphic profile. SSI has a specialized research library. (author)

  20. Swedish radiation protection institute. Information activities

    Persson, Lars

    1999-01-01

    The purpose of SSI's information and PR Service is to broaden public awareness of radiation and radiation risks as well as to fulfil other performance goals. SSI achieves this through its advisory, educational and informative activities. SSI publishes two external magazines, Straalskyddsnytt and SSI News. Straalskyddsnytt - which is available in Swedish only - has a circulation of 2,400 and is published four times a year. SSI News - which is in English - is published twice a year and has a circulation of about 1,500. Another important channel of communication is the web site (www.ssi.se). Taking advantage of PUSH technology, SSi also distributes, by e-mail, press releases and other important information of radiation to radiation protection professionals in Sweden. SSI continuously monitors news by subscribing to a press clipping service. SSI Training is a commercial unit within the Information and PR Service. A policy for mass media contacts exists as well as a policy for internal communication. SSI has a graphic profile. SSI has a specialised research library. (au)

  1. Trace elemental composition of Nigerian coal measured by neutron activation analysis

    Ndiokwere, Ch.L.; Guinn, V.P.; Burtner, D.

    1983-01-01

    The instrumental neutron activation analysis (INAA) technique has been used to determine 17 major, minor and trace elements in samples of the three major sources of Nigerian coal. The NBS Standard Reference Material, Coal SRM 1632, was also analyzed, for the purpose of verifying the accuracy of the method. The concentrations of the major elements determined for the Nigerian coal were found to be much lower than the mean values of those reported for coal samples from other parts of the world. (author)

  2. Determination of trace elements in a cigarette paper by neutron activation analysis

    Abedinzadeh, Z.; Khalkhali, Zh.; Razeghi, M.; Parsa, B.

    The concentration of 19 trace elements in a cigarette paper (Zig-Zag Paper Company, France) which is used in making different brands of Iranian cigarettes, has been measured by neutron activation analysis, employing a high-resolution Ge(Li) detector. They include Na, K, Ca, Sc, Cr, Mn, Fe, Co, Zn, Br, Sr, Sb, Ba, Ce, Eu, Gd, Au, Hg, and Th. (author)

  3. Determination of trace element impurities in aspirin tablets by neutron activation analysis

    Iskander, F.Y.; Klein, D.E.; Bauer, T.L.

    1986-01-01

    Twenty-five trace and minor elements in five different Egyptian aspirin brands (Aspo, Askin, Aspocid, Aspeol and Rivo) were determined by instrumental neutron activation analysis. It was concluded that the concentration of As, Ba, Br, Co, Cr, Fe (except in Aspocid), Mg, Mn, Rb, Se, Sr and Zn in the Egyptian brands is below or within the concentration range reported for these elements in 16 American aspirin and aspirin-like brands. (author)

  4. Simultaneous speciation of trace elements using chemical separation and neutron activation

    Chatt, A.

    2003-01-01

    Speciation neutron activation analysis (SNAA) is a sophisticated analytical technique which can be developed for studying the simultaneous speciation of a number of elements in a variety of matrices. The advantages of SNAA are demonstrated with typical examples such as (i) arsenic speciation in sea foods and water, and simultaneous speciation of (ii) arsenic, antimony and selenium in water, (iii) chlorine, bromine and iodine in fish, (iv) lanthanides in simulated vitrified waste, and (v) trace elements bound to proteins. (author)

  5. Neutron activation analysis as applied to instrumental analysis of trace elements from seawater

    Boniforti, R.; Moauro, A.; Madaro, M.

    1983-01-01

    Particulate matter collected from the coastal area delimited by the mouth of the river Volturno and the Sabaudia lake has been analyzed by instrumental neutron activation analysis for its content of twenty-two trace elements. The results for surface water and bottom water are reported separately, thus evidencing the effect of sampling depth on the concentration of many elements. The necessity of accurately 'cleaning' the filters before use is stressed

  6. Trace element analysis at the Livermore pool-type reactor using neutron activation techniques

    Ragaini, R.C.; Ralston, R.; Garvis, D.

    1975-01-01

    The capabilities of trace element analysis at the Livermore Pool-Type Reactor (LPTR) using instrumental neutron activation analysis (INAA) are discussed. A description is given of the technology and the methods employed, including sample preparation, irradiation, and analysis. Applications of the INAA technique in past and current projects are described. A computer program, GAMANAL, has been used for nuclide identification and quantification. (U.S.)

  7. Determination of trace elements in chewing gum by neutron activation analysis

    Dietz, M.L.

    1990-01-01

    Six trace elements of nutritional or toxicological interest (Al, Ca, Cl, Mn, Na and Sr) were determined in three different brands of chewing gum by instrumental neutron activation analysis. For the particular brands of gum examined, none of the detected elements was found to be present at a level representing a substantial contribution to the total dietary intake of the element for an American adult. (author) 11 refs.; 3 tabs

  8. Trace element characterisation of New Zealand obsidian using neutron activation analysis

    Chidgey, R.Y.

    1982-01-01

    The aim of this study was to assess the suitability of neutron activation data for characterising New Zealand obsidian through the application of multivariate statistics. The trace element concentrations were corrected for flux variation. NAA has the advantage of permitting measurements of concentrations of many elements to a sensitivity of less than 1 ppm. Furthermore, effects caused by weathering or mineral inclusions will not bias the measurements

  9. A Novel Hybrid Model for Drawing Trace Reconstruction from Multichannel Surface Electromyographic Activity.

    Chen, Yumiao; Yang, Zhongliang

    2017-01-01

    Recently, several researchers have considered the problem of reconstruction of handwriting and other meaningful arm and hand movements from surface electromyography (sEMG). Although much progress has been made, several practical limitations may still affect the clinical applicability of sEMG-based techniques. In this paper, a novel three-step hybrid model of coordinate state transition, sEMG feature extraction and gene expression programming (GEP) prediction is proposed for reconstructing drawing traces of 12 basic one-stroke shapes from multichannel surface electromyography. Using a specially designed coordinate data acquisition system, we recorded the coordinate data of drawing traces collected in accordance with the time series while 7-channel EMG signals were recorded. As a widely-used time domain feature, Root Mean Square (RMS) was extracted with the analysis window. The preliminary reconstruction models can be established by GEP. Then, the original drawing traces can be approximated by a constructed prediction model. Applying the three-step hybrid model, we were able to convert seven channels of EMG activity recorded from the arm muscles into smooth reconstructions of drawing traces. The hybrid model can yield a mean accuracy of 74% in within-group design (one set of prediction models for all shapes) and 86% in between-group design (one separate set of prediction models for each shape), averaged for the reconstructed x and y coordinates. It can be concluded that it is feasible for the proposed three-step hybrid model to improve the reconstruction ability of drawing traces from sEMG.

  10. Determination of trace elements in seawater using Mg-scavenger as preconcentration agent, and neutron activation analysis

    Andersen, B.

    1986-01-01

    In order to determine trace elements in seawater, a preconsentration method based on coprecipitation on Mg(OH) 2 is presented. Different parameters influencing the carrying effects have been investigated using model solutions and radioactive tracers. The deposit and solution are separated by filtration. Filter with deposit is stored in quarts ampules for later determination of trace elements by means of neutron activation analysis

  11. Radiation effects on active pixel sensors (APS)

    Cohen, M.; David, J.P.

    1999-01-01

    Active pixel sensor (APS) is a new generation of image sensors which presents several advantages relatively to charge coupled devices (CCDs) particularly for space applications (APS requires only 1 voltage to operate which reduces considerably current consumption). Irradiation was performed using 60 Co gamma radiation at room temperature and at a dose rate of 150 Gy(Si)/h. 2 types of APS have been tested: photodiode-APS and photoMOS-APS. The results show that photoMOS-APS is more sensitive to radiation effects than photodiode-APS. Important parameters of image sensors like dark currents increase sharply with dose levels. Nevertheless photodiode-APS sensitivity is one hundred time lower than photoMOS-APS sensitivity

  12. Radiation protection activities around the CERN accelerators

    Fasso, A.

    1996-01-01

    In 1995 several operational circumstances required careful watching by the Radiation Protection Group. Most of these were linked with new or recently started CERN activities: for instance the increasing importance assumed by ISOLDE operation and the breakdowns encountered which have given rise to contamination of the target region and to activity releases. In the SPS ring, several difficulties were brought about by a toilsome installation of a new interlock system, while lead ion operation marked the end of the year, as usual, with higher radiation levels in the SPS experimental areas, despite the fact that existing shielding had been improved. Also at the end of the year, the increase of LEP beam energy to 68 GeV caused a rise of dose rate levels from synchrotron radiation. This was expected, but studies are still needed to assess the full implications for different aspects of radiation protection. On the other hand, the ageing of magnet coils and other equipment (insulators, cables, flexible pipes), aggravated by the high proton beam intensities, has resulted in an increasing frequency of failures (mainly water leaks) both at the PS and at the SPS. If the apparent trend is confirmed, difficulties could be expected in the future for two reasons: the shortage of specialized staff, some of them approaching the CERN dose limit of 15 mSv annually, who can be assigned to repair work; and the lack of spare parts to replace the damaged items. Luckily, the long cooling times following high intensity proton runs provided by the operation with heavy-ions and by the winter shutdown mitigate this situation

  13. Trace elements detection in whole food samples by Neutron Activation Analysis, k0-method

    Sathler, Márcia Maia; Menezes, Maria Ângela de Barros Correia; Salles, Paula Maria Borges de

    2017-01-01

    Inorganic elements, from natural and anthropogenic sources are present in foods in different concentrations. With the increase in anthropogenic activities, there was also a considerable increase in the emission of these elements in the environment, leading to the need of monitoring the elemental composition of foods available for consumption. Numerous techniques have been used to detect inorganic elements in biological and environmental matrices, always aiming at reaching lower detection limits in order to evaluate the trace element content in the sample. Neutron activation analysis (INAA), applying the k 0 -method, produces accurate and precise results without the need of chemical preparation of the samples – that could cause their contamination. This study evaluated the presence of inorganic elements in whole foods samples, mainly elements on trace levels. For this purpose, seven samples of different types of whole foods were irradiated in the TRIGA MARK I IPR-R1 research reactor - located at CDTN/CNEN, in Belo Horizonte, MG. It was possible to detect twenty two elements above the limit of detection in, at least, one of the samples analyzed. This study reaffirms the INAA, k 0 - method, as a safe and efficient technique for detecting trace elements in food samples. (author)

  14. Trace elements detection in whole food samples by Neutron Activation Analysis, k{sub 0}-method

    Sathler, Márcia Maia; Menezes, Maria Ângela de Barros Correia, E-mail: maia.sathler@gmail.com, E-mail: menezes@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Salles, Paula Maria Borges de, E-mail: pauladesalles@yahoo.com.br [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

    2017-07-01

    Inorganic elements, from natural and anthropogenic sources are present in foods in different concentrations. With the increase in anthropogenic activities, there was also a considerable increase in the emission of these elements in the environment, leading to the need of monitoring the elemental composition of foods available for consumption. Numerous techniques have been used to detect inorganic elements in biological and environmental matrices, always aiming at reaching lower detection limits in order to evaluate the trace element content in the sample. Neutron activation analysis (INAA), applying the k{sub 0}-method, produces accurate and precise results without the need of chemical preparation of the samples – that could cause their contamination. This study evaluated the presence of inorganic elements in whole foods samples, mainly elements on trace levels. For this purpose, seven samples of different types of whole foods were irradiated in the TRIGA MARK I IPR-R1 research reactor - located at CDTN/CNEN, in Belo Horizonte, MG. It was possible to detect twenty two elements above the limit of detection in, at least, one of the samples analyzed. This study reaffirms the INAA, k{sub 0} - method, as a safe and efficient technique for detecting trace elements in food samples. (author)

  15. Method to determine trace elements in water samples by neutron activation analysis

    Kueppers, G.; Erdtmann, G.

    1981-05-01

    For the determination of trace elements in water by neutron activation analysis irradiation porcedures and chemical separation procedures have been developed. Irradiation in melted quarz glass ampoules in the presence of a platinum wire (for recombination of the oxyhydrogen gas produced by radiolysis) proved successfull with different variants of the irradiation methods, as long irradiation periods without pressure build-up could be achieved. Possible falsifications of the analysis results were investigated in detail (losses by absorption on vessel walls etc.). The irradiated samples can be measured directly with a gamma ray spectrometer and from the radionuclides found the trace element contents may be calculated. More sensitive determinations are possible if the radionuclides are chemically separated. Procedures for removing the matrix activities, for the separation of the radionuclides in groups of elements and for the isolation of single elements have been developed. For especially sensitive determination of some elements selective separation procedures for antimony, cadmium, selenium, mercury and uranium have been developed. The analytical procedures described have been applied to trace element determinations in river water, glacier ice and water solutions from technical processes. (orig./RB) [de

  16. Determination of short-lived trace elements in environmental samples by neutron activation analysis

    Wardani, S.; Sihombing, E.; Hamzah, A.; Rochidi; Hery, P.S.; Hartaman, S.; Iman, J.

    1998-01-01

    Concentration of a short-lived trace elements in environmental samples were determined by neutron activation analysis, a counting loss often occur due to the high counting rate. A Pile-Up Rejecter (PUR) electric circuit was installed in counting a short-lived trace elements by a γ-ray spectrometer in order to correct a counting loss. The samples were irradiated for 30∼60 seconds at neutron flux of 3.5 x 10 12 n.cm -2 .s -1 , then the samples cooled for 120 second and counted for 180 second using this system. The nuclides concentration in the varieties environmental samples have a difference analysis result, was more accurate and precise, which the measured result would be 30 % more higher by PUR system than the result would be counted using a conventional γ-ray spectrometry method

  17. Trace elements in Turkish tobacco determined by instrumental neutron activation analysis

    Gulovali, M.C.

    1977-01-01

    This study was undertaken to determine the concentration of trace elements in nine different brands of Turkish cigarette tobacco, pipe tobacco and tobacco ash. Instrumental neutron activation analysis was employed, and a gamma-ray spectrometer consisting of 40 cm 3 Ge(Li) detector coupled to 1024 and 4096-channel analyzers were used. Samples were irradiated at a thermal neutron flux of about 10 13 cm -2 sec -1 . Concentrations of Na, K, Sc, Cr, Fe, Co, Zn, As, Se, Br, Rb, Sb, Cs, Ba, La, Ce, Eu, Hf, Hg and Th were determined in tobacco and ash; percent transference of these elements into ash were calculated. It was found out that trace elements in cigarette tobacco are left in the ash but only a small percentage is transferred into the smoke

  18. Radiochemical neutron activation analysis for trace elements of basic ingredients of pan

    Zaidi, J.H.; Arif, M.; Fatima, I; Qureshi, I.H.

    2002-01-01

    Extensive use of pan, by one-tenth of world's population, entails the evaluation of trace element contents in its ingredients. Radiochemical neutron activation analysis (RNAA) was developed and successfully employed to determine the concentration of 36 trace elements (essential, toxic and nonessential) in its four basic ingredients, leaf of betel pepper, betel nut, catechu and lime. The radiochemical separation methodology has significantly improved the detection limits of most of these elements due to suppression of Compton background. Base-line values of certain toxic and essential elements in these ingredients is provided. The daily intake of essential and toxic elements through pan was estimated and compared with the recommended values. The cumulative intake of Mn is four times higher than the recommended value and that of toxic elements is well below the tolerance limits. (author)

  19. Determination of trace elements by neutron activation analysis using dinonylnaphtalene sulfonic acid as a preconcentrating agent

    Yang, M.H.; Chen, P.Y.; Tseng, C.L.; Yeh, S.J.; Weng, P.S.

    1977-01-01

    Dinonylnaphthalene sulfonic acid (HD) has been used as a preconcentrating agent to enrich trace metal ions and to separate the interfering elements such as Na, K, Cl and Br, which normally exist in the natural aqueous systems. Experiments were performed by extracting the ions in the aqueous medium with HD in n-hexane and subsequently backextracted into a minimal volume of acid solution. Factors influencing the extraction efficiency of the ions of interest were investigated. The preconcentration technique has been successfully applied to the determination by neutron activation analysis of trace elements in natural water and biological materials. Both short-lived nuclides (Mg, Al, Ca, Mn) and long-lived nuclides (Sm, Eu, Zn, La, Cr, Sc, Fe, Co) in the ppb-level concentrations were determined. (T.G.)

  20. Effect of Trace Elements in Alcohol Beverages on the Type of Radiation-induced Cell Death

    Sohn, Jong Gi

    2010-01-01

    Developments of radioprotective agents are important issues for minimizing the troubles and the effective treatments in radiotherapy. But few agents are useful in clinical and practical fields. It was shown that trace elements in alcohol beverages might have radioprotective effect. In this study, the types of cell death of lymphocytes according to the commercial alcohol beverage was investigated. Normal healthy volunteers ingested distilled water, beer or soju containing 8.15 mg·dl -1 ethyl ahcohol, respectively. After 2 hours, their blood were sampled with their consents. Fraction of lymphocytes was isolated by density gradient method with Histopaque-1077 (Sigma) and irradiated with dose from 0.5 to 5 Gy. After 60 hour incubation, the cells were harvested and analysed by flow cytometry. Cell viability was decreased by dose dependent manner. Cell viability of beer group was reduced about 15% compared with control group. Apoptosis in soju group was reduced about 20% compared with control group. Apoptosis of beer and control groups are similar. Necrosis of soju group significantly increased about 35% compared with control group. Early apoptosis of beer group was increased compared with control group. Early apoptosis of soju group was decreased about 25% compared with control group. Late apoptosis of beer and control group was increased by dose dependent manner. Late apoptosis of soju group was increased about 20-30% compared with control group. Late apoptosis of soju was increased and the radioprotective effect of soju was minimal because late apoptosis induced the cell necrosis. In case of soju trace elements, total cell apoptosis was decreased about 20% and early cell apoptosis was remarkably low. In this case, mitotic cells death may be dominant mechanism. Therefore, trace elements in soju may not be effective radioprotective agents

  1. Utilization of synchrotron radiation for trace-element analyses in toxicology of metals

    Hanson, A.L.; Jones, K.W.; Kraner, H.W.; Gordon, B.M.; Chen, J.R.

    1983-01-01

    The use of SXRF will nicely complement other more widely used analytical techniques for trace elements. The experiments at CHESS showed minimum detectable limits for 1-mm thick organic matrices with monochromated photon beams to be on the order of 160 to 300 ppB for Ni to Sr with minimal structural damage to the material being irradiated. Extrapolations to operating conditions at the NSLS, with a facility designed for XRF, indicate the MDL limits of 10 to 100 ppB should be achievable. The utilization of wavelength dispersive detectors should gain an order of magnitude in sensitivity, but with trade-off of some flexibility in multielemental analyses

  2. Trace element determination in soft tissues of marine bivalves by activation analysis

    Fukushima, M.; Tamate, H.; Nakano, Y.

    2003-01-01

    Trace elements in soft tissues of marine bivalves were determined by neutron activation analysis (NAA) and photon activation analysis (PAA). Elemental levels of Ag, As, Br, Co, Cu, Fe, I, Mn, Ni, Rb, Se, and Zn in the organs of giant ezoscallos, rock oysters, and giant crams were obtained. The metal-bound proteins were extracted from the mantles and hepatopancreases of rock oysters. By irradiating the fraction obtained by HPLC gel chromatography, the possibility for the existence of an Ag bound protein in the mantles was found. (author)

  3. Addition of granular activated carbon and trace elements to favor volatile fatty acid consumption during anaerobic digestion of food waste.

    Capson-Tojo, Gabriel; Moscoviz, Roman; Ruiz, Diane; Santa-Catalina, Gaëlle; Trably, Eric; Rouez, Maxime; Crest, Marion; Steyer, Jean-Philippe; Bernet, Nicolas; Delgenès, Jean-Philippe; Escudié, Renaud

    2018-07-01

    The effect of supplementing granular activated carbon and trace elements on the anaerobic digestion performance of consecutive batch reactors treating food waste was investigated. The results from the first batch suggest that addition of activated carbon favored biomass acclimation, improving acetic acid consumption and enhancing methane production. Adding trace elements allowed a faster consumption of propionic acid. A second batch proved that a synergy existed when activated carbon and trace elements were supplemented simultaneously. The degradation kinetics of propionate oxidation were particularly improved, reducing significantly the batch duration and improving the average methane productivities. Addition of activated carbon favored the growth of archaea and syntrophic bacteria, suggesting that interactions between these microorganisms were enhanced. Interestingly, microbial analyses showed that hydrogenotrophic methanogens were predominant. This study shows for the first time that addition of granular activated carbon and trace elements may be a feasible solution to stabilize food waste anaerobic digestion. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Distribution of trace elements in whole blood of Syrian lymphomas patients using instrumental neutron activation analysis

    Bakir, M. A.; Serhil, A.; Mohammad, A.; Habil, K.

    2013-12-01

    In recent years, there had been much interest in the concentrations of trace metals occurring in human and animal tissues and in the manner in which these concentrations may alter in malignant and other diseases. Neutron activation analysis is consider one of several methods that have been described for the determination of trace elements in biological materials. This method possesses the sensitivity and specificity necessary for the estimation at the concentrations existing naturally in most tissues, particularly when only small samples are available for analysis. The purpose of this study was to compare blood concentrations of trace elements Co, Cr, Fe, Rb, Sc, Se, Th, and Zn of lymphomas Syrian patients with those of healthy volunteers. Also, determine the relationships between trace elements concentration and the histological type of lymphomas. The blood samples were collected from 39 healthy volunteers and 49 patients with histologically confirmed lymphomas (29 Hodgkin's HL and 20 non-Hodgkin's lymphomas NHL), and analyzed to obtain the concentration of the trace elements in blood. Then, comparison between the healthy volunteers and lymphomas patients (both HL and NHL) was made to elucidate differences of the concentration distributions of the elements in blood. However, statistical analysis using Student's t test revealed significantly high concentrations of Co, Cr, Sc, and Th in lymphoma patients. Whereas Fe and Rb were found significantly decreased in lymphomas patient comparing to control group. Increasing or decreasing concentrations of Se and Zn in lymphoma patients was found not significant. Comparison between the healthy volunteers and non-Hodgkin's lymphomas patients reveled that Co, Cr, Sc, and Th were significantly elevated whereas, Rb only one trace element was decreased and all change in concentrations (elevating or decreasing) of Se and Zn were not significant. Comparison between the healthy volunteers and Hodgkin

  5. A fast and efficient adaptive parallel ray tracing based model for thermally coupled surface radiation in casting and heat treatment processes

    Fainberg, J; Schaefer, W

    2015-01-01

    A new algorithm for heat exchange between thermally coupled diffusely radiating interfaces is presented, which can be applied for closed and half open transparent radiating cavities. Interfaces between opaque and transparent materials are automatically detected and subdivided into elementary radiation surfaces named tiles. Contrary to the classical view factor method, the fixed unit sphere area subdivision oriented along the normal tile direction is projected onto the surrounding radiation mesh and not vice versa. Then, the total incident radiating flux of the receiver is approximated as a direct sum of radiation intensities of representative “senders” with the same weight factor. A hierarchical scheme for the space angle subdivision is selected in order to minimize the total memory and the computational demands during thermal calculations. Direct visibility is tested by means of a voxel-based ray tracing method accelerated by means of the anisotropic Chebyshev distance method, which reuses the computational grid as a Chebyshev one. The ray tracing algorithm is fully parallelized using MPI and takes advantage of the balanced distribution of all available tiles among all CPU's. This approach allows tracing of each particular ray without any communication. The algorithm has been implemented in a commercial casting process simulation software. The accuracy and computational performance of the new radiation model for heat treatment, investment and ingot casting applications is illustrated using industrial examples. (paper)

  6. Determination of trace elements in airborne particulates by instrumental neutron activation analysis

    Jung, Yong Sam; Jung, Yung Joo; Jung, Eui Sik; Cho, Seung Yun

    1995-01-01

    Trace elements in airborne particulates were analyzed by instrumental neutron activation analysis(INAA) under the optimum analytical condition. Neutron irradiation for sample was done at the irradiation hole(neutron flux, 1 x 10 13 n/cm 2 s) of TRIGA MARK-III research reactor in the Korea Atomic Energy Research Institute. For the verification of the analytical method, NIST SRM-1648 and NIES CRM No.8 were chosen and analyzed. The accuracy and precision of the analysis of 40 and 24 trace elements in the samples were compared with the certified and reported values, respectively. The analytical method was found to be reliable enough when the analytical data of NIES sample were compared with those of different countries. In the analytical result of two or both of standard reference materials, relative standard deviation was within the 15% except a few elements and the relative error was within the 10%. We used this method to analyze 30 trace elements in airborne particulates collected with the high volume air sampler(PM-10) at two different locations and also confirmed the possibility to use this method as a routine monitoring tool to find out environmental pollution sources. 3 figs., 8 tabs., 19 refs. (Author)

  7. Trace Elements in Human Myocardial Infarction Determined by Neutron Activation Analysis

    Wester, P.O.

    1965-05-01

    By means of neutron activation analysis, injured and adjacent uninjured human heart tissue from 12 autopsy cases with myocardial infarction are investigated with respect to the concentration of 23 trace elements. The bulk elements K, Na and P are also determined. A recently developed ion-exchange technique, combined with subsequent y-spectrometry, is used. The following trace elements are determined: Ag, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Rb, Sb, Sc, Se, Sm, Zn and W. In the injured tissue compared to the uninjured, calculation on a wet weight basis showed a decrease in Co, Cs, K, Mo, P, Rb and Zn, and an increase in Br, Ca, Ce, La, Na, Sb and Sm. The differences in Ca, La, Mo, P and Zn are dependent on the age of the myocardial infarction, and the regression lines for these elements are given. The concentration of the trace elements in uninjured tissue from infarcted hearts is compared to the concentration of these elements in normal heart tissue, determined in a previous study. In the uninjured tissue from infarcted hearts a decrease is found in Cu and Mo, and an increase in As and Ce

  8. Trace Elements in Human Myocardial Infarction Determined by Neutron Activation Analysis

    Wester, P O

    1965-05-15

    By means of neutron activation analysis, injured and adjacent uninjured human heart tissue from 12 autopsy cases with myocardial infarction are investigated with respect to the concentration of 23 trace elements. The bulk elements K, Na and P are also determined. A recently developed ion-exchange technique, combined with subsequent y-spectrometry, is used. The following trace elements are determined: Ag, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Rb, Sb, Sc, Se, Sm, Zn and W. In the injured tissue compared to the uninjured, calculation on a wet weight basis showed a decrease in Co, Cs, K, Mo, P, Rb and Zn, and an increase in Br, Ca, Ce, La, Na, Sb and Sm. The differences in Ca, La, Mo, P and Zn are dependent on the age of the myocardial infarction, and the regression lines for these elements are given. The concentration of the trace elements in uninjured tissue from infarcted hearts is compared to the concentration of these elements in normal heart tissue, determined in a previous study. In the uninjured tissue from infarcted hearts a decrease is found in Cu and Mo, and an increase in As and Ce.

  9. Investigation of trace elements in Elbe water by means of instrumental neutron activation analysis

    Motamedi, K.

    1977-01-01

    Investigations of trace elements in Elbe water were carried out as a contribution to environmental research, hydrology, and geochemistry. The method applied - instrumental neutron activation analysis - is described, and problems connected with the course of analysis - sample taking, handling and preparation as well as optimization of in-pile irradiation and measurement by means of γ spectrometry - are discussed and presented one by one. The computer programme set up for automatic evaluation is described in more detail. This programme AKAN has a very general concept which makes it applicable for general use. The reliability of the evaluation procedure - monostandard method - and the reproducibility of the results are discussed. For the studies, samples were taken at different times, every time from 8 positions along a long section of the Elbe. The content of solids was analyzed; in a number of samples, this was done by separating suspended and dissolved materials. Up to 38 elements were analyzed, whose local and time-dependent concentration curves are given. The contents of some elements are compared with the few available data from literature. Correlation calculations indicate a similar behaviour of single element groups and yield information on the natural origin of the trace elements and on anthropogenic influence to be noticed in the trace element contents. (orig.) [de

  10. The effects of trace elements, cations, and environmental conditions on protocatechuate 3,4-dioxygenase activity

    Andréa Scaramal da Silva

    2013-04-01

    Full Text Available Phenanthracene is a highly toxic organic compound capable of contaminating water and soils, and biodegradation is an important tool for remediating polluted environments. This study aimed to evaluate the effects of trace elements, cations, and environmental conditions on the activity of the protocatechol 3,4-dioxygenase (P3,4O enzyme produced by the isolate Leifsonia sp. in cell-free and immobilized extracts. The isolate was grown in Luria Bertani broth medium (LB amended with 250 mg L-1 of phenanthrene. Various levels of pH (4.0-9.0, temperature (5-80 °C, time (0-90 min, trace elements (Cu2+, Hg2+ and Fe3+, and cations (Mg2+, Mn2+, K+ and NH4+ were tested to determine which conditions optimized enzyme activity. In general, the immobilized extract exhibited higher enzyme activity than the cell-free extract in the presence of trace elements and cations. Adding iron yielded the highest relative activity for both cell-free and immobilized extracts, with values of 16 and 99 %, respectively. Copper also increased enzyme activity for both cell-free and immobilized extracts, with values of 8 and 44 %, respectively. Enzyme activity in the phosphate buffer was high across a wide range of pH, reaching 80 % in the pH range between 6.5 and 8.0. The optimum temperatures for enzyme activity differed for cell-free and immobilized extracts, with maximum enzyme activity observed at 35 ºC for the cell-free extract and at 55 ºC for the immobilized extract. The cell-free extract of the P3,4O enzyme exhibited high activity only during the first 3 min of incubation, when it showed 50 % relative activity, and dropped to 0 % after 60 min of incubation. By contrast, activity in the immobilized extract was maintained during 90 min of incubation. This isolate has important characteristics for phenanthrene biodegradation, producing high quantities of the P3,4O enzyme that forms part of the most important pathway for PAH biodegradation.

  11. Semiautomatic imputation of activity travel diaries : use of global positioning system traces, prompted recall, and context-sensitive learning algorithms

    Moiseeva, A.; Jessurun, A.J.; Timmermans, H.J.P.; Stopher, P.

    2016-01-01

    Anastasia Moiseeva, Joran Jessurun and Harry Timmermans (2010), ‘Semiautomatic Imputation of Activity Travel Diaries: Use of Global Positioning System Traces, Prompted Recall, and Context-Sensitive Learning Algorithms’, Transportation Research Record: Journal of the Transportation Research Board,

  12. Radiation From Solar Activity | Radiation Protection | US EPA

    2017-08-07

    Solar flares, coronal mass ejections (CMEs) and geomagnetic storms from the sun can send extreme bursts of ionizing radiation and magnetic energy toward Earth. Some of this energy is in the form ionizing radiation and some of the energy is magnetic energy.

  13. Activation analysis of hair as an indicator of contamination of man by environmental trace element pollutants

    Ryabukhin, Yu.S.

    1976-10-01

    The burning of fossil fuel, discharges from metallurgical and chemical plants, the wide use of chemicals, and other human activities, result in releasing into the biosphere large quantities of elements which are found in relatively low concentrations in the human organism. The pollution of the biosphere by such trace elements, and in particular heavy metals, has reached such proportions that on the scale of significance of the factors causing the 'stressed' state of the environment of heavy metals occupy the second place and, according to forecasts, may in the future move on to the first. In the problem of pollution of the biosphere, man himself undoubtedly occupies the central position as a target. The pollution of air, soil and water, the contamination of micro-organisms, plants and animals are certainly growing into a serious threat and leading to heavy losses. However, it would be a real disaster if man himself became contaminated to levels giving rise to large scale harmful somatic or genetic effects. It is therefore an urgent problem today to determine the initial levels of trace elements in man and the extent of his contamination in areas where these elements are expected to show anomalous concentrations. Attention should be paid in the first place to those trace elements which probably play no physiological role, are particularly abundant in the environment, and have high toxicity (arsenic, mercury, lead, cadmium, etc.). Moreover, it should be born in mind that in anomalously high concentrations even the physiologically necessary trace elements (copper, zinc, manganese, fluorine, etc.) cause harmful effects. This paper justifies the use of hair samples as a biological indicator of environmental pollutants from physiological and morphological aspect and recommends on sample preparation and analysis methods

  14. Activation analysis of hair as an indicator of contamination of man by environmental trace element pollutants

    Ryabukhin, Yu S [ed.

    1976-10-01

    The burning of fossil fuel, discharges from metallurgical and chemical plants, the wide use of chemicals, and other human activities, result in releasing into the biosphere large quantities of elements which are found in relatively low concentrations in the human organism. The pollution of the biosphere by such trace elements, and in particular heavy metals, has reached such proportions that on the scale of significance of the factors causing the 'stressed' state of the environment of heavy metals occupy the second place and, according to forecasts, may in the future move on to the first. In the problem of pollution of the biosphere, man himself undoubtedly occupies the central position as a target. The pollution of air, soil and water, the contamination of micro-organisms, plants and animals are certainly growing into a serious threat and leading to heavy losses. However, it would be a real disaster if man himself became contaminated to levels giving rise to large scale harmful somatic or genetic effects. It is therefore an urgent problem today to determine the initial levels of trace elements in man and the extent of his contamination in areas where these elements are expected to show anomalous concentrations. Attention should be paid in the first place to those trace elements which probably play no physiological role, are particularly abundant in the environment, and have high toxicity (arsenic, mercury, lead, cadmium, etc.). Moreover, it should be born in mind that in anomalously high concentrations even the physiologically necessary trace elements (copper, zinc, manganese, fluorine, etc.) cause harmful effects. This paper justifies the use of hair samples as a biological indicator of environmental pollutants from physiological and morphological aspect and recommends on sample preparation and analysis methods.

  15. Radiation-chemical degradation of traces of trichloroethylene and perchloroethylene in drinking water

    Gehringer, P.; Proksch, E.; Szinovatz, W.; Eschweiler, H.

    1986-01-01

    The degradation caused by gamma irradiation of traces of trichloroethylene and perchloroethylene in certain water samples has been investigated over a wide range of concentrations. In general, the degradation is the slower, the higher the concentration of organic and inorganic substances (especially of nitrates) dissolved in the respective water. For pollutant concentrations up to about 500 ppb and for drinking water with rather low nitrate content (some ppm) the degradation follows a first-order rate law. For higher concentrations of pollutants or/and nitrates a much more complex behaviour is observed. In general, perchloroethylene is degraded slower than trichloroethylene. During degradation, organic chlorine is converted quantitatively to chloride ions. Unfortunately, as a side reaction nitrate is partially reduced to nitrite. Except for that, first rough estimates resulted in costs which seem to render such a process economically quite attractive. (orig.) [de

  16. Activity report of Synchrotron Radiation Laboratory 2005

    2006-11-01

    Since 1980s, the Synchrotron Radiation Laboratory (SRL) has been promoting the 'Super-SOR' project, the new synchrotron radiation facility dedicated to sciences in vacuum ultraviolet and soft X-ray regions. The University of Tokyo considered the project as one of the most important future academic plans and strongly endorsed to construct the new facility with an electron storage ring of third generation type in the Kashiwa campus. During last year, the design of the accelerator system was slightly modified to obtain stronger support of the people in the field of bio-sciences, such as medicine, pharmacy, agriculture, etc. The energy of the storage ring was increased to 2.4 GeV, which is determined to obtain undulator radiation with sufficient brightness in X-ray region for the protein crystallography experiments. The value was also optimised to avoid considerable degradation of undulator radiation in the VUV and soft X-ray regions. However, in October last year, the president office of the University found out that the promotion of the project was very difficult for financial reasons. The budget for the new facility project is too big to be supported by a single university. The decision was intensively discussed by the International Review Committee on the Institute for Solid State Physics (ISSP), which was held at ISSP from November 14 to 16. The committee understood that the restructuring of the University system in Japan would overstrain the financial resources of the University of Tokyo and accepted the decision by the University. Presently, SRL has inclined to install beamlines using undulator radiation in other SR facilities instead of constructing a facility with a light source accelerator. At new beamlines, SRL will promote advanced materials sciences utilizing high brilliance and small emittance of synchrotron radiation which have been considered in the Super-SOR project. They are those such as microscopy and time-resolved experiments, which will only be

  17. Effect of heat treatment on anodic activation of aluminium by trace element indium

    Graver, Brit [Department of Materials Science and Engineering, Norwegian University of Science and Technology, N-7491 Trondheim (Norway); Helvoort, Antonius T.J. van [Department of Physics, Norwegian University of Science and Technology, N-7491 Trondheim (Norway); Nisancioglu, Kemal, E-mail: kemal.nisancioglu@material.ntnu.n [Department of Materials Science and Engineering, Norwegian University of Science and Technology, N-7491 Trondheim (Norway)

    2010-11-15

    Research highlights: {yields} Indium segregation activates AlIn alloy surface anodically in chloride solution. {yields} Enrichment of In on Al surface can occur thermally by heat treatment at 300 {sup o}C. {yields} Increasing temperature homogenises indium in aluminium reducing anodic activation. {yields} Indium can activate AlIn surface by segregating through dealloying of aluminium. {yields} Anodic activation is caused by AlIn amalgam formation at aluminium surface. - Abstract: The presence of trace elements in Group IIIA-VA is known to activate aluminium anodically in chloride environment. The purpose of this paper is to investigate the surface segregation of trace element In by heat treatment and resulting surface activation. Model binary AlIn alloys, containing 20 and 1000 ppm by weight of In, were characterized after heat treatment at various temperatures by use of glow discharge optical emission spectroscopy, electron microscopy and electrochemical polarization. Heat treatment for 1 h at 300 {sup o}C gave significant segregation of discrete In particles (thermal segregation), which activated the surface. Indium in solid solution with aluminium, obtained by 1 h heat treatment at 600 {sup o}C, also activated by surface segregation of In on alloy containing 1000 ppm In, resulting from the selective dissolution of the aluminium component during anodic oxidation (anodic segregation). The effect of anodic segregation was reduced by decreasing indium concentration in solid solution; it had negligible effect at the 20 ppm level. The segregated particles were thought to form a liquid phase alloy with aluminium during anodic polarization, which in turn, together with the chloride in the solution destabilized the oxide.

  18. Radiation epidemiological analysis of late effects of population exposure at northern part of east ural radioactive trace

    Yarmoshenko, I.V.; Konshina, L.G.; Lezhnin, V.L.; Zhukovsky, M.V.; Pavlyuk, A.V.

    2006-01-01

    Population residing in the northern part of the Chelyabinsk oblast and the south eastern part of the Sverdlovsk oblast of Russia affected to accidental exposure since 1957. The territory (East Ural Radioactive Trace - EURT) was contaminated after explosion of container with highly radioactive wastes at the Mayak Production Association. Studies of health effects of exposure in the southern, head part of EURT are conducted in the Ural Research and Practical Center of Radiation Medicine (U.R.P.R.M.). In the 1990's U.R.P.C.R.M. formed a cohort of EURT within Chelyabinsk oblast (14,500 cases and 19,400 external controls). The cohort was followed in 1957-1987 and the results of the study are discussed by Crestinina et al. First results of study on exposure late health effects among rural population in the northern part of the EURT are presented in this paper. Firstly, or the period 1958-2000 a statistically significant increase in cancer mortality associated with accidental exposure at EURT area was observed in the critical group of population of the Kamensky district, Sverdlovsk Region (65 cancer deaths among 691 cases, 90% CI 18-144). The finding is in agreement with the results of a radiation epidemiological study in the southern head part of EURT and model radiation risk assessments. E.R.R. normalized to colon dose is 1.3 Gy-1 (90 % CI 0.36-2.9 Gy-1). Secondly, analysis of the age and temporal factors influence on solid cancers radiation risk allows conclusion on decline of radiation risk in time. At present considerable number of additional radiation-induced cancer deaths are unlikely to appear. Radiation risk of solid cancers realizes at most during 30 post-accident years. Radiation risk declines with age at first exposure and not appeared in the age group >60. Derived age and time dependencies generally agree with results of other radiation epidemiological studies. Thirdly, continuation and development of radiation epidemiological study of the population residing

  19. Radiation epidemiological analysis of late effects of population exposure at northern part of east ural radioactive trace

    Yarmoshenko, I.V.; Konshina, L.G.; Lezhnin, V.L.; Zhukovsky, M.V.; Pavlyuk, A.V. [V.N. Chukanov Institute of Industrial Ecology UB RAS, Yekaterinburg (Russian Federation)

    2006-07-01

    Population residing in the northern part of the Chelyabinsk oblast and the south eastern part of the Sverdlovsk oblast of Russia affected to accidental exposure since 1957. The territory (East Ural Radioactive Trace - EURT) was contaminated after explosion of container with highly radioactive wastes at the Mayak Production Association. Studies of health effects of exposure in the southern, head part of EURT are conducted in the Ural Research and Practical Center of Radiation Medicine (U.R.P.R.M.). In the 1990's U.R.P.C.R.M. formed a cohort of EURT within Chelyabinsk oblast (14,500 cases and 19,400 external controls). The cohort was followed in 1957-1987 and the results of the study are discussed by Crestinina et al. First results of study on exposure late health effects among rural population in the northern part of the EURT are presented in this paper. Firstly, or the period 1958-2000 a statistically significant increase in cancer mortality associated with accidental exposure at EURT area was observed in the critical group of population of the Kamensky district, Sverdlovsk Region (65 cancer deaths among 691 cases, 90% CI 18-144). The finding is in agreement with the results of a radiation epidemiological study in the southern head part of EURT and model radiation risk assessments. E.R.R. normalized to colon dose is 1.3 Gy-1 (90 % CI 0.36-2.9 Gy-1). Secondly, analysis of the age and temporal factors influence on solid cancers radiation risk allows conclusion on decline of radiation risk in time. At present considerable number of additional radiation-induced cancer deaths are unlikely to appear. Radiation risk of solid cancers realizes at most during 30 post-accident years. Radiation risk declines with age at first exposure and not appeared in the age group >60. Derived age and time dependencies generally agree with results of other radiation epidemiological studies. Thirdly, continuation and development of radiation epidemiological study of the population

  20. Evaluation of trace elements in different species of lichens by neutron activation analysis

    Coccaro, D.M.B.; Saiki, M.; Vasconcellos, M.B.A.

    2000-01-01

    Instrumental neutron activation analysis has been applied for the determination of trace elements in five epiphytic lichens: Canoparmelia texana, Canoparmelia caroliniana, Parmotrema tinctorum, Parmotrema sancti-angeli and Usnea sp. that were collected at the same sampling area of the Botanic Institute, Sao Paulo, Brazil. The elemental concentration results showed that these five lichens can be chosen in the species intercalibration for biomonitoring studies. Also, some aspects related to the occurrence, tolerance to pollution, treatment and ease of sampling of the species are presented. (author)

  1. Determination of trace elements in poly(methyl methacrylate) by neutron activation analysis

    Kobayashi, M.

    1979-01-01

    The results are reported of the neutron activation analysis of poly(methyl methacrylate) polymerized with a redox system of chromium (II) acetate and p-chlorobenzyl peroxide in dimethylformamide at 30 0 C. Since the polymer was originally synthesized in experiments for kinetic studies, the results indicate an arbitrary background of purity of polymers obtained in a laboratory. Samples were irradiated for 28m and gamma spectra detected trace amounts of chlorine, aluminum, vanadium, magnesium, manganese, potassium, copper, zinc, sodium, bromine, lanthanum, gold, and chromium. 2 figures, 1 table

  2. Photon activation analysis of trace metals in the livers and spleens of pigs

    Fukushima, M.

    1995-01-01

    Nondestructive photon activation analysis with 30 MeV bremsstrahlung was applied to determine trace element concentrations in the livers and spleens of five pigs. Samples were freeze-dried, pulverized and fractionated into four groups corresponding mesh size ; smaller than 60 mesh, 60-100 mesh, 100-200 mesh and larger than 200 mesh. Up to 9 elements in each fraction were analyzed. The concentrations of Br, Fe, Mg, Mn, Mo, Na, Rb and Zn in each liver fractions were almost constant, as were concentrations of Mg and Rb in spleens. (author). 10 refs., 7 tabs

  3. Determination of trace elements in human brain tissues using neutron activation analysis

    Leite, R.E.P.; Jacob-Filho, W.; Grinberg, L.T.; Ferretti, R.E.L.

    2008-01-01

    Neutron activation analysis was applied to assess trace element concentrations in brain tissues from normal (n = 21) and demented individuals (n = 21) of both genders aged more than 50 years. Concentrations of the elements Br, Fe, K, Na, Rb, Se and Zn were determined. Comparisons were made between the results obtained for the hippocampus and frontal cortex tissues, as well as, those obtained in brains of normal and demented individuals. Certified reference materials, NIST 1566b Oyster Tissue and NIST 1577b Bovine Liver were analyzed for quality of the analytical results. (author)

  4. Determination of trace elements in bottled water in Greece by instrumental and radiochemical neutron activation analyses

    Soupioni, M.J.; Symeopoulos, B.D.; Papaefthymiou, H.V.

    2006-01-01

    Four different bottled water brands sold in Greece in the winter of 2001-2002 were analyzed for a wide range of chemical elements, using neutron activation analysis (NAA). The elements Na and Br were determined instrumentally (INAA), whereas the other metals and trace elements radiochemically (RNAA). The results indicated that the mean level of all the elements determined in the samples were well within the European Union (EU) directive on drinking water and accomplish the drinking water standards of the World Health Organisation (WHO) as well as of the Food and Drug Administration (FDA). (author)

  5. Activation analysis in a multitechnique study of trace element imbalances in age-related neurological diseases

    Ehmann, W.D.; Ding, X.X.; Khare, S.S.; Lovell, M.A.; Ni, B.F.; Tandon, L.; Vance, D.E.; Wenstrup, D.E.

    1993-01-01

    It has been suggested that several age-related neurological diseases such as Alzheimer's disease and amyotrophic lateral sclerosis may be related to environmental toxins. Bulk sample multielemental analyses by INAA alone are not adequate to define the role of trace elements in these diseases. A multitechnique approach has been developed that incorporates 14 MeV, instrumental reactor, radiochemical, and pre-irradiation chemical neutron activation analysis, together with laser microprobe mass spectrometry. The analytical scheme is able to provide bulk or protein normalized elemental concentrations, as well as microstructural, cellular, and subcellular localization information. (author) 21 refs.; 3 figs.; 3 tabs

  6. Trace elements in cigarette tobacco by a method of instrumental neutron activation analysis

    Noordin Ibrahim

    1986-01-01

    A total of ten cigarette brands were investigated for determining the trace elemental concentrations in tobacco so as to assess their role in the induction of related diseases through smoking. A method instrumental Neutron Activation analysis was employed due to high sensitivity, speed and ability to analyse sample for a wide spectrum of elements simultaneously. A total of 18 elements were detected of which the majority are toxic elements. A full result and conclusion will be reported in the forthcoming paper. (A.J.)

  7. Neutron activation analysis of trace metals in the livers of Japanese sika deer (cervus Nippon)

    Fukushima, Michiko; Tamate, Hidetoshi; Sasaki, Yoshiro; Mitsugasira, Satoaki; Masumoto, Kazuyoshi.

    1997-01-01

    Neutron activation analysis facilities at the JMTR reactor was used to determine the levels of trace metals in the livers of nine Japanese sika deer. The samples were cut into pieces, pulverized in liquid nitrogen, freeze-dried, and finally fractionated through a stainless steel sieve of 200 mesh. Then the samples were irradiated for 6 or 24 hours by a neutron flux of 1.0x10 14 n·cm -2 ·sec -1 . In the present work, we analysed the concentrations of six elements (Ag, Co, Fe, Rb, Se, and Zn) in the livers of nine deer. (author)

  8. Trace aluminium determination and sampling problems of archeological bone employing destructive neutron activation analysis

    Blotcky, A.J.; Rack, E.P.; Recker, R.R.; Leffler, J.A.; Teitelbaum, S.

    1978-01-01

    A destructive neutron activation analysis procedure was developed for determining trace aluminium content in bone. The method is based on a carefully planned sample preparation, irradiation at a neutron flux for 3.1x10 11 nxcm -2 xs -1 for 5 minutes, and chemical separation based on ion exchange. It was found that bone samples soaked in aluminium containing soil gave highly elevated aluminium values as a result of the aluminium adsorption into the bone matrix. The maximum aluminium content values for prehistoric bones are larger than those of modern bones and comparable to aluminium levels present in bone from renal patients. (T.G.)

  9. The determination of trace elements in new food grain SRM's using neutron activation analysis

    Gills, T.E.; Gallorini, M.; Rook, H.L.

    1978-01-01

    Potentially toxic metals in the food chain that can lead to deleterious effects on human health have been well documented. Because of the toxicity of some metals, levels of 1 ppm or less must be routinely monitored in foods to ensure human safety. To ensure the accuracy of measurement, NBS in a cooperative interagency agreement with the Food and Drug Administration is involved in developing and certifying selected elements in food grain as a part of the Standard Reference Material program. Both instrumental and radiochemical neutron activation analysis were used to analyze two food grain standard reference materials (Rice and Wheat Flours) for trace element certification. (author)

  10. Correction of trace element levels in breast cancer during radiation treatment

    Shkala, L.V.

    1997-01-01

    New method for microelement metabolism correction in patients with comedocarcinoma exposed to radiotherapy was developed and applied. Telegammatherapy was performed 5 time a week at a single dose of 2 Gy, cumulative dose of 40-45 Gy. The method consists in using Trilon B (heavy metal complexone) for correction of microelement metabolism and cupping the syndrome of radiation reactions in combination with dimexide possessing radioprotective properties

  11. Centrifugal Tensioned Metastable Fluid Detectors for Trace Radiation Sources: Experimental Verification and Military Employment

    2016-06-01

    tube PSD pulse shape discrimination Pu plutonium SF spontaneous fission SNM special nuclear material STP standard temperature and pressure U...independent terrorist organization that is able to purchase a nuclear weapon on the black market and smuggle it into the United States. The...can travel up to a few feet in air at STP [6]. Beta particles, as with other forms of ionizing radiation, can also cause damage to certain living

  12. Antimicrobial activity, phyto chemical profile and trace minerals of black mulberry (morus nigra l.) fresh juice

    Khalid, N.; Fawad, S.A.; Ahmed, I.

    2011-01-01

    In the present work, the fresh juice of black mulberry (Morus nigra) was tested for antimicrobial activity against various pathogenic microorganisms. Total antioxidant contents, total phenolic contents, total anthocyanins, trace minerals, total acid contents, total solids and ascorbic acid content were also evaluated. The results showed good antimicrobial activity both for Gram- positive and Gram-negative bacteria, with highest zones of inhibition for Bacillus spizizenii (19.68 mm, Gram-positive) and Pseudomonas aeruginosa (19.87 mm, Gram-negative). The black mulberry juice was rich in ascorbic acid (23.45 mg/100 g), had low overall acid content (1.60 %) and had 19% total soluble solids. The average total anthocyanins and total phenolic contents of black mulberry juice were 769 mu g/g of cyanidin 3-glucoside equivalent (Cy 3-gly) per gram and 2050 mu g of gallic acid equivalent (GAE) per gram of fresh juice. The average antioxidant activity (Trolox equivalent, TE) of fresh juice was 14.00 mu mol/g according to a FRAP assay and 20.10 mu mol/g according to a DPPH assay. The fresh juice was also rich in a variety of trace minerals. (author)

  13. Ray-tracing 3D dust radiative transfer with DART-Ray: code upgrade and public release

    Natale, Giovanni; Popescu, Cristina C.; Tuffs, Richard J.; Clarke, Adam J.; Debattista, Victor P.; Fischera, Jörg; Pasetto, Stefano; Rushton, Mark; Thirlwall, Jordan J.

    2017-11-01

    We present an extensively updated version of the purely ray-tracing 3D dust radiation transfer code DART-Ray. The new version includes five major upgrades: 1) a series of optimizations for the ray-angular density and the scattered radiation source function; 2) the implementation of several data and task parallelizations using hybrid MPI+OpenMP schemes; 3) the inclusion of dust self-heating; 4) the ability to produce surface brightness maps for observers within the models in HEALPix format; 5) the possibility to set the expected numerical accuracy already at the start of the calculation. We tested the updated code with benchmark models where the dust self-heating is not negligible. Furthermore, we performed a study of the extent of the source influence volumes, using galaxy models, which are critical in determining the efficiency of the DART-Ray algorithm. The new code is publicly available, documented for both users and developers, and accompanied by several programmes to create input grids for different model geometries and to import the results of N-body and SPH simulations. These programmes can be easily adapted to different input geometries, and for different dust models or stellar emission libraries.

  14. Determination of Heavy and Toxic Trace Elements in Sediments of Qarun Lake Using Instrumental Neutron Activation Analysis Technique

    Hamed, A.; Abd EI-Samad, M.; Soliman, N.F.

    2011-01-01

    An investigation of certain heavy and toxic trace elements in 15 sediment samples from different areas at Qarun Lake was performed by a neutron activation technique using the neutron irradiation facilities of the Second Egyptian Research Reactor (ETRR-2). The samples together with two sets of gold foils (one bare and the other covered with cadmium) and two Standard Reference Materials IAEA (Soil-7) were irradiated at the core of the reactor in two capsules for 8520 seconds, another two capsules each has two sets of gold foils (one bare and the other covered with cadmium) are used to determine the neutron fluxes around the sediment samples. The gamma-rays of nuclides from the irradiated samples were carried out by means of a well calibrated high resolution HPGe detection system. The concentrations of product nuclides containing in the irradiated samples were determined from the peak counting-rates of the prominent gamma-ray lines for the corresponding nuclides using Single External Comparator Method (k 0 -Standardization Method) which called k 0 -NAA technique. The neutron flux ratios (f) in the same radiation sites of the sediment samples bottles were calculated as well as the cadmium ratios (R e d). MS Excel work books were constructed and used in our calculation. The total contents of As , Ba , Ca ,Co, Cr ,Cs, Eu ,Hf ,Hg,Na ,Ru ,Sc ,Se ,Sm ,Sn ,Sr ,Th ,Rb ,Zn ,and Zr in these samples were measured. The objectives .of this study were evaluated to identify the variations of concentration of some elements that have an impact on environmental pollutions. The results indicated that the concentrations of toxic trace elements of Ba, Cr, Se, Sn, Hg, Sin and Zn may represent pollutions problem

  15. Kaolinite: a natural radiations dosemeter. Application to past radioelement migrations tracing in the geosphere

    Allard, Thierry

    1994-01-01

    The efficiency of the processes regulating the mobility of the radioelements in the geosphere can be assessed by the study of past migrations of uranium. For that geochemical purpose, it can be used mineral tracers like kaolinite, which records past contacts with radioelements as radiation-induced defects. Three radiation-induced centers had been identified in kaolinite by means of electron paramagnetic resonance, i.e. the A-, A'- and B-centers, and interpreted as hole centers located on oxygen atoms of the structure. The A-center is stable at the scale of geological periods. Consequently, it could be directly used to measure paleo-doses, that are related to the past occurrence of radioelements. This works states the potentialities of kaolinite as a dosimeter for the study or past migrations of uranium in the geosphere: - Experimental irradiations: we studied the effects of the main natural radiations (alpha and gamma) within a dose range consistent with that occurring in geo-systems at the Earth surface. We simulated these radiation effects by irradiating natural reference kaolinites with He + ions provided by the ARAMIS particle accelerator (Orsay) and a 60 Co source (CENG, Grenoble), respectively. We took into account the natural variability of kaolinites in terms of crystalline disorder and chemical (Fe 3+ ) or mineralogical (illite, smectite) impurities. It is confirmed that the sensitivity of the radiation-induced centers decreases in the order B>A>A'. The dosimetry curve of the A center can be described with an exponential function constrained by two parameters (the concentration at saturation and the efficiency coefficient) which are correlated. These dosimetry parameters are also correlated with the crystalline order of the kaolinites, which suggests the possibility to assess them by a measurement of crystalline disorder (with EPR). Moreover, the alpha irradiations of illite and of smectite evidenced radiation centers, which can disturb the EPR

  16. Grain tracing and strain determination in a Be compact tension specimen using synchrotron radiation

    Varma, R.; Green, R.; Garcia, M.D.; Satyam, P.V.; Yun, W.B.; Maser, J.; Kai, Z.; Lai, B.; Sinha, S.K.

    1999-01-01

    X-ray synchrotron radiation of high (11 KeV) energy and high flux (10 10 photons per square centimeter per second) has been used to measure strains and polycrystallinity in 6-mm thick polycrystalline beryllium compact tension (CT) specimens at and around the crack tip (for fatigue-precracked sample) or at chevron notch point under load or no-load conditions. The authors demonstrated the feasibility strain field mapping as well as determining the polycrystallinity at or near the points of maximum load in beryllium CT specimens. The experimental techniques and results will be discussed

  17. Active microphonic noise cancellation in radiation detectors

    Zimmermann, Sergio

    2013-01-01

    A new adaptive filtering technique to reduce microphonic noise in radiation detectors is presented. The technique is based on system identification that actively cancels the microphonic noise. A sensor is used to measures mechanical disturbances that cause vibration on the detector assembly, and the digital adaptive filtering estimates the impact of these disturbances on the microphonic noise. The noise then can be subtracted from the actual detector measurement. In this paper the technique is presented and simulations are used to support this approach. -- Highlights: •A sensor is used to measures mechanical disturbances that cause vibration on the detector assembly. •Digital adaptive filtering estimates the impact of these disturbances on the microphonic noise. •The noise is then subtracted from the actual detector measurement. •We use simulations to demonstrate the performance of this approach. •After cancellation, we recover most of the original energy resolution

  18. Application of neutron activation analysis to the monitoring of trace elements in Brazilian foodstuffs

    Vasconcellos, M.B.A.; Maihara, V.A.; Munita, C.J.A.S.; Favaro, D.I.T.; Armelin, M.J.A.

    1994-01-01

    Due to lack of data on trace element levels in Brazilian foodstuffs, nuclear analytical techniques were used to determine about twenty elements in foods samples collected from local markets of the city of Sao Paulo. Drinking water was also analyzed. The methods employed were mainly instrumental and radiochemical neutron activation analysis. In the case of the analysis of toxic elements, such as mercury, selenium, arsenic and antimony, the purely instrumental approach failed in yielding results for very low concentrations of these elements. For INAA, samples and multielemental synthetic standards were irradiated in the IEA R1 research reactor for periods of time ranging from minutes to several hours, under thermal neutron fluxes from 10 11 to 10 13 n·cm -2 ·s -1 ; after suitable cooling times, γ-ray spectra were measured using a Ge(Li) or Ge solid state detector. The RNAA approach involved the distillation of mercury and selenium in HBr medium; selenium was then reduced to the metal form with sodium metabisulphide and mercury was precipitated as sulphide with thioacetamide. For water analysis, a preconcentration procedure based on retention of several elements in a Chelex-100 resin was employed. The elements retained were Hg, Cr, Zn, Fe, Co while Se was measured in the effluent after absorption on active charcoal. The levels of the trace inorganic elements determined in the Brazilian foodstuffs analyzed were always below the levels established by the existing regulations in our country. (author). 16 refs, 18 tabs

  19. Determination of Trace Elements In Soil and Plants In Coastal Basin of Syria By Using Instrumental Neutron Activation Analysis

    Kassem, A.

    2004-01-01

    Instrumental neutron activation analysis (INAA) methods have been used for the determination of some major, minor and trace elements (As, Cr, Co, Ni, Zn, Sb, Sc Ce, Ti, Fe, Mn and V) in some kinds of plant leaves with their soil. Accuracy of measurements have been evaluated by analyzing a number of plant and soil reference materials, precision have been estimated by triplicate the sample as well as the reference. The obtained accurate and reliable data in microgram quantities of some trace elements in plants and soil will serve as baseline values and will be helpful to monitor the changes in the trace elements content of soil and plant leaves. (Author)

  20. Tracing footprints of environmental events in tree ring chemistry using neutron activation analysis

    Sahin, Dagistan

    The aim of this study is to identify environmental effects on tree-ring chemistry. It is known that industrial pollution, volcanic eruptions, dust storms, acid rain and similar events can cause substantial changes in soil chemistry. Establishing whether a particular group of trees is sensitive to these changes in soil environment and registers them in the elemental chemistry of contemporary growth rings is the over-riding goal of any Dendrochemistry research. In this study, elemental concentrations were measured in tree-ring samples of absolutely dated eleven modern forest trees, grown in the Mediterranean region, Turkey, collected and dated by the Malcolm and Carolyn Wiener Laboratory for Aegean and Near Eastern Dendrochronology laboratory at Cornell University. Correlations between measured elemental concentrations in the tree-ring samples were analyzed using statistical tests to answer two questions. Does the current concentration of a particular element depend on any other element within the tree? And, are there any elements showing correlated abnormal concentration changes across the majority of the trees? Based on the detailed analysis results, the low mobility of sodium and bromine, positive correlations between calcium, zinc and manganese, positive correlations between trace elements lanthanum, samarium, antimony, and gold within tree-rings were recognized. Moreover, zinc, lanthanum, samarium and bromine showed strong, positive correlations among the trees and were identified as possible environmental signature elements. New Dendrochemistry information found in this study would be also useful in explaining tree physiology and elemental chemistry in Pinus nigra species grown in Turkey. Elemental concentrations in tree-ring samples were measured using Neutron Activation Analysis (NAA) at the Pennsylvania State University Radiation Science and Engineering Center (RSEC). Through this study, advanced methodologies for methodological, computational and

  1. Discrete curved ray-tracing method for radiative transfer in an absorbing-emitting semitransparent slab with variable spatial refractive index

    Liu, L.H.

    2004-01-01

    A discrete curved ray-tracing method is developed to analyze the radiative transfer in one-dimensional absorbing-emitting semitransparent slab with variable spatial refractive index. The curved ray trajectory is locally treated as straight line and the complicated and time-consuming computation of ray trajectory is cut down. A problem of radiative equilibrium with linear variable spatial refractive index is taken as an example to examine the accuracy of the proposed method. The temperature distributions are determined by the proposed method and compared with the data in references, which are obtained by other different methods. The results show that the discrete curved ray-tracing method has a good accuracy in solving the radiative transfer in one-dimensional semitransparent slab with variable spatial refractive index

  2. A neutron activation study of trace element contents in plants growing on soils of different acidity

    Caplan, J.; Loebersli, E.; Steinnes, E.; Naeumann, R.

    1987-01-01

    As a part of a research program on the influence of soil acidification on metal uptake in plants, the present work was carried out in order to investigate the feasibility of instrumental neutron activation analysis for this purpose. The work was restricted to elements yielding medium- or long-lived radionuclides on neutron activation. Elements studied include Na, Sc, Cr, Fe, Co, Zn, Br, Rb, Cs, Ba and La. The material analyzed was from a comparison of trace element contents in natural vegetation from corresponding coniferous forest locations in South Norway, which is considerably exposed to acidic deposition from long-range atmospheric transport, and Central Norway, which is far less affected. In particular, Rb and Cs show pronounced differences between the two regions regarding concentration levels in certain plant species. (author) 8 refs.; 4 figs

  3. A neutron activation study of trace element contents in plants growing on soils of different acidity

    Caplan, J.; Loebersli, E.; Naeumann, R.; Steinnes, E.

    1986-01-01

    As part of a research program on the influence of soil acidification on metal uptake in plants, the present work was carried out in order to investigate the feasibility of instrumental neutron activation analysis for this purpose. The work was restricted to elements yielding medium- or long-lived radionuclides on neutron activation. Elements studied include Na, Sc, Cr, Ge, Co, Zn, Br, Rb, Cs, Ba and La. The material analyzed was from a comparison of trace element contents in natural vegetation from corresponding coniferous forest locations in South Norway, which is considerably exposed to acidic deposition from long-range atmospheric transport, and Central Norway, which is far less affected. In particular Rb and Cs show pronounced differences between the two regions regarding concentration levels in certain plant species. (author)

  4. Determination of trace elements of Egyptian crops by neutron activation analysis Pt. 3

    Sherif, M.K.; Awadallah, R.M.; Amrallah, A.H.

    1980-01-01

    Multielemental neutron activation analysis was used for the determination of Al, As, Au, Br, Ca, Cd, Co, Cr, Cu, Fe, La, Mn, Mo, Sb, Se, W and Zn in African tea and lady's fingers (Malvaceae Family), ginger (Zingiperanceae Family), canella bark (Laureceae Family), black pepper (Piperaceae Family), cucumber seeds and vegetable marrow seeds (Cucurbitaceae Family), tomatos seed (Solanaceae Family), safflower seeds (Compositae Family), jew's mallow seed (Tiliaceae Family) and sesame (Pedaliaceae Family). Trace elements determination was made for the analysis of destructive (using super pure nitric acid and adsorbing the metal-APDC and metal-Dz complexes on activated charcoal) and nondestructive (dry seeds) samples. The method is simple, precise and sensitive for the determination of microamounts of the elements (ppm to ppb). (author)

  5. Activity report of Synchrotron Radiation Laboratory 2001

    2002-11-01

    After moved from Tanashi to Kashiwa Campus in the spring of 2000, the Synchrotron Radiation Laboratory (SRL) has been promoting the High-brilliance Light Source project, Super SOR project, in cooperation with the nationwide user group as well as with the users of the University of Tokyo. In May of 2001, the project has met with a dramatic progress. The Ministry of Education, Science, Sports and Culture organized the Advisory Board and started to discuss the future synchrotron radiation facilities in EUV and SX regime in Japan. Based on extensive discussion, they proposed the new facility consisting of a 1.8 GeV storage ring of 3rd generation type. The University of Tokyo approved to construct the proposed facility in the Kashiwa campus. The plan is supported not only by researchers in academic institutions but also bio- and chemical-industries. We strongly hope the plan will be realized in near future. On the other hand, SRL maintains a branch laboratory in the Photon Factory (PF) High Energy Accelerator Research Organization (KEK) at Tsukuba with a Revolver undulator, two beamlines and three experimental stations (BL-18A, 19A and 19B), which are and fully opened to the outside users. In the fiscal year of 2001, the operation time of the beamlines was more than 5000 hours and the number of the users was about 200. The main scientific interests and activities in the SRL at KEK-PF are directed to the electronic structures of new materials with new transport, magnetic and optical properties. The electronic structures of solid surfaces and interfaces are also intensively studied by photoelectron spectroscopy and photoelectron microscopy. The accelerator group of SRL is carrying out research works of the accelerator physics and developing the accelerator-related technology, many parts of which will be directly applied to the new light source project. This report contains the activities of the staff members of SRL and users of the three beamlines in FY2001. The status of

  6. Report on radiation protection calibration activities in Australia

    Hargrave, N.J.

    1995-01-01

    Australia is a federation of eight autonomous States or Territories. Each of these is responsible for many matters including radiation safety within their borders. National matters are the responsibility of the Federal Government. The Australian Radiation Laboratory (ARL) is a part of the Federal Government Department of Human Services and Health and undertakes research and service activities related to radiation health. Work related to both ionising and non ionising radiation and regulatory matters is performed. Some of the research activities relate to radiation measurement standards, environmental radioactivity (e.g. radon in air, radioactivity in drinking water), effects of electro-magnetic fields on health (ELF), ultra violet radiation (UV) and laser safety, radiochemistry, medical applications of radiation (and doses to the population as a result), general health physics, thermoluminescent dosimetry (TLD) and electron spin resonance (ESR) dosimetry. The calibration of protection instruments are undertaken by the Ionising Radiation Standards Group within the Laboratory and by State Health Laboratories. (J.P.N.)

  7. European activities in radiation protection in medicine

    Simeonov, Georgi

    2015-01-01

    The recently published Council Directive 2013/59/Euratom ('new European Basic Safety Standards', EU BSS) modernises and consolidates the European radiation protection legislation by taking into account the latest scientific knowledge, technological progress and experience with implementing the current legislation and by merging five existing Directives into a single piece of legislation. The new European BSS repeal previous European legislation on which the national systems for radiation protection in medicine of the 28 European Union (EU) Member States are based, including the 96/29/Euratom 'BSS' and the 97/43/ Euratom 'Medical Exposure' Directives. While most of the elements of the previous legislation have been kept, there are several legal changes that will have important influence over the regulation and practice in the field all over Europe-these include, among others: (i) strengthening the implementation of the justification principle and expanding it to medically exposed asymptomatic individuals, (ii) more attention to interventional radiology, (iii) new requirements for dose recording and reporting, (iv) increased role of the medical physics expert in imaging, (v) new set of requirements for preventing and following up on accidents and (vi) new set of requirements for procedures where radiological equipment is used on people for non-medical purposes (nonmedical imaging exposure). The EU Member States have to enforce the new EU BSS before January 2018 and bring into force the laws, regulations and administrative provisions necessary to comply with it. The European Commission has certain legal obligations and powers to verify the compliance of the national measures with the EU laws and, wherever necessary, issue recommendations to, or open infringement cases against, national governments. In order to ensure timely and coordinated implementation of the new European legal requirements for radiation protection, the Commission is

  8. Trace Elements in the Conductive Tissue of Beef Heart Determined by Neutron Activation Analysis

    Wester, P.O.

    1965-08-01

    By means of neutron activation analysis, samples of four beef hearts taken from the bundle of His and adjacent ventricular muscle, the AV node and adjacent atrial muscle are investigated with respect to the concentration of 23 trace elements. The bulk elements K, Na and P are also determined. A recently developed ion-exchange technique, combined with subsequent γ-spectrometry, is used. The following trace elements are determined: Ag, As, Au, Ba, Br, .Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Rb, Sb, Sc, Se, Sm, W and Zn. In the conductive tissue compared to adjacent muscle tissue, calculations on a wet weight basis show a lower concentration of Cs, Cu, Fe, K, P, Rb and Zn in the former, and a higher concentration of Ag, Au, Br, Ca and Na. The mean differences (μg/g wet tissue), as well as their degree of significance, between the bundle of His and adjacent tissue from the ventricular septum, between the AV node and adjacent atrial muscle, between the ventricular septum and the right atrium, and between the bundle of His and the AV node are given for the elements Cu, Fe, K, Na, P and Zn

  9. Determination of trace elements in Mesozoic dykes of the Serra do Mar by neutron activation

    Vicentini, Caio M.; Marques, Leila S.

    2013-01-01

    The analysis of trace elements such as rare earths, Th, U, Ta, Hf, Ba, Rb and Ba, is a very important tool for petrogenetic studies. In order to study these processes in dykes of Enxame Serra do Mar (Coast of Sao Paulo and Rio de Janeiro), belonging to the Parana Magmatic Province (PMP), one of the most significant provinces of continental basalts in the world, were perform analyzes by neutron activation in these dikes. The technique, employed in Centro de Reator de Pesquisa of the Instituto de Pesquisas Energeticas e Nucleares, provided concentrations of trace elements with accuracy levels of 10% and 9%, which are suitable for petrogenetic studies. Due to the low concentrations of the elements analyzed, the experimental routine sample preparation processes covered very careful to avoid contamination. The samples investigated can be divided into four groups: basic rocks (SiO 2 500; basic rocks with Ti / Y 2 2 > 63%). Dikes of intermediate and acid composition only occur at the Sao Sebastiao Island and adjacent coastal region. The concentrations of major and minor elements, as well as the abundance patterns of rare earths and other incompatible elements of these more differentiated rocks, show significant similarities with the type of the volcanic Chapeco, suggesting similar genesis, in other worlds, including also processes of crustal contamination

  10. Trace Elements in the Conductive Tissue of Beef Heart Determined by Neutron Activation Analysis

    Wester, P O

    1965-08-15

    By means of neutron activation analysis, samples of four beef hearts taken from the bundle of His and adjacent ventricular muscle, the AV node and adjacent atrial muscle are investigated with respect to the concentration of 23 trace elements. The bulk elements K, Na and P are also determined. A recently developed ion-exchange technique, combined with subsequent {gamma}-spectrometry, is used. The following trace elements are determined: Ag, As, Au, Ba, Br, .Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Rb, Sb, Sc, Se, Sm, W and Zn. In the conductive tissue compared to adjacent muscle tissue, calculations on a wet weight basis show a lower concentration of Cs, Cu, Fe, K, P, Rb and Zn in the former, and a higher concentration of Ag, Au, Br, Ca and Na. The mean differences ({mu}g/g wet tissue), as well as their degree of significance, between the bundle of His and adjacent tissue from the ventricular septum, between the AV node and adjacent atrial muscle, between the ventricular septum and the right atrium, and between the bundle of His and the AV node are given for the elements Cu, Fe, K, Na, P and Zn.

  11. Determination of trace elements: Neutron-activation analysis in geochemistry and cosmochemistry

    Kolesov, G.M.

    1994-01-01

    Geochemistry, like cosmochemistry, open-quotes studies chemical elements hor-ellipsis of the crust and hor-ellipsis the Earth hor-ellipsis their history, their distribution hor-ellipsis their genetic hor-ellipsis connectionsclose quotes and is based on data on the abundance and distribution of elements obtained by various analytical methods. Neutron-activation analysis (NAA) plays a particular role in this respect. This is due to its high sensitivity (detection limit as small as 10 -14 g), which makes possible the use of samples of arbitrary mass, and also due to the possibility of obtaining information about composition without destruction of the object, conserving, if required, the unique material under investigation. Of the most interest are the data on the contents for a number of trace elements (at a level of 10 -7 - 10 -4 %), among which are rare-earth elements (REE), U, Th, Zr, Hf, Ta, W, Ga, Ni, Rb, Cs, platinum-group metals, Ag, Au, etc. These elements are considered as indicators of geochemical processes associated with the genesis and evolution of solar system bodies in early and more recent stages of evolution; they are also used to study processes and phenomena at zone boundaries: river-sea, ocean-atmosphere, and so on. The aim of this work is to show the capabilities of NAA in the determination of trace elements

  12. Trace elements determinations in cancerous and non-cancerous human tissues using instrumental neutron activation analysis

    Choi, Insup.

    1989-01-01

    Recent improvements in analyzing techniques when coupled to the growing knowledge of trace element biochemistry provide a powerful tool to investigate the relationship between trace elements and cancer. It is hoped that selective delivery or restriction of specific minerals may aid in cancer prevention or treatment. Tissues were collected at the time of surgery of various cancer patients including colon cancer and breast cancer. Three kinds of tissues were taken from a patient; cancerous, noncancerous, and transitional tissue obtained from a region located between the cancer and healthy tissues. A total of 57 tissues were obtained from 19 cancer patients. Seven of them were colon cancer patients, and 5 of them were breast cancer patients. Nine elements were determined using instrumental activation analysis. Cancerous colon tissue had significantly higher concentrations of selenium and iron than healthy tissues. Cancerous breast tissue had significantly higher concentrations of selenium, iron, manganese, and rubidium than healthy tissues. Iron can be enriched in cancer tissue because cancer tissue retains more blood vessels. Selenium is enriched in cancer tissue, possibly in an effort of the body to inhibit the growth of tumors. The manganese enrichment can be explained in the same manner as selenium considering its suspected anticarcinogenicity. It is not certain why rubidium was enriched in cancer tissue. It could be that this is the result of alteration of cell membrane permeability, change in extracellular matrix, or increased metabolism in cancer tissue

  13. Trace element contents in atmospheric suspended particles: inferences from instrumental neutron activation analysis

    Querol, X.; Alastuey, A.; Lopez-Soler, A.; Boix, A.; Sanfeliu, T.; Martynov, V.V.; Piven, P.I.; Kabina, L.P.; Souschov, P.A.

    1997-01-01

    This study focuses on the determination of trace element concentrations in total suspended particles by instrumental neutron activation analysis (INAA) in two different areas in Northeastern Spain (a rural area influenced by the emissions of a large coal-fired power station, and the urban and industrial areas of Castellon). Total suspended particles were sampled by means of standard MCV high- and medium-volume captors, using cellulose membrane filters of 0.8 and 0.45 μm pore size. Preliminary research was performed on the homogeneous distribution of elements in the sample filters and on the study of blank filters for the calculations of the background average element contents. The results obtained allowed to distinguish different major anthropogenic sources of trace elements in the atmosphere at the sampling sites: (a) Zr, Hf, Sc, U and Th are related to atmospheric pollution derived from the ceramic industry of the Castellon area; (b) As, Cr, Cs, Rb, Sb, Se, Zn are related to traffic and other industrial emission in the Castellon area, and As, Cr, Sb and Zn to power generation emissions in the rural area. (orig.). With 3 figs., 5 tabs

  14. Evaluation of Diversity Antenna Designs Using Ray Tracing, Measured Radiation Patterns, and MIMO Channel Measurements

    Arindam Pal

    2007-01-01

    Full Text Available This paper presents an evaluation of the MIMO performance of three candidate antenna array designs, each embedded within a PDA footprint, using indoor wideband channel measurements at 5.2 GHz alongside channel simulations. A channel model which employs the plane-wave approximation was used to combine the embedded antenna radiation patterns of the candidate devices obtained from far-field pattern measurements and multipath component parameters from an indoor ray-tracer. The 4-element candidate arrays were each constructed using a different type of antenna element, and despite the diverse element directivities, pattern characteristics, and polarization purities, all three devices were constructed to fully exploit diversity in polarization, space, and angle. Thus, low correlation and high information theoretic capacity was observed in each case. A good match between the model and the measurements is also demonstrated, especially for 2×2 MIMO subsets of identically or orthogonally polarized linear slot antennas. The interdependencies between the channel XPD, directional spread and pathloss, and the respective impact on channel capacity are also discussed in this paper.

  15. Evaluation of Diversity Antenna Designs Using Ray Tracing, Measured Radiation Patterns, and MIMO Channel Measurements

    Pal Arindam

    2007-01-01

    Full Text Available This paper presents an evaluation of the MIMO performance of three candidate antenna array designs, each embedded within a PDA footprint, using indoor wideband channel measurements at 5.2 GHz alongside channel simulations. A channel model which employs the plane-wave approximation was used to combine the embedded antenna radiation patterns of the candidate devices obtained from far-field pattern measurements and multipath component parameters from an indoor ray-tracer. The 4-element candidate arrays were each constructed using a different type of antenna element, and despite the diverse element directivities, pattern characteristics, and polarization purities, all three devices were constructed to fully exploit diversity in polarization, space, and angle. Thus, low correlation and high information theoretic capacity was observed in each case. A good match between the model and the measurements is also demonstrated, especially for MIMO subsets of identically or orthogonally polarized linear slot antennas. The interdependencies between the channel XPD, directional spread and pathloss, and the respective impact on channel capacity are also discussed in this paper.

  16. Determination of trace elements in wool fibre by instrumental neutron activation analysis and relation between trace element contents and quality of wool

    Eozyol, H.

    1990-01-01

    Wool samples were analyzed by neutron activation analysis and 17 elements, Al, Ag, Au, As, Br, Ca, Co, Cr, Cu, Fe, La, Mg, Mn, Na, Sb, Se and Zn were measured quantitatively. The presence of seven others, Ce, Eu, I, Mo, Te and W was noted. Since several elements, such as Cd, Hg and Pb could not be conveniently determined by NAA, Atomic Absorption Spectroscopy (AAS) was used instead. Cu and Zn were also analyzed by NAA and AAS to compare these two methods. Mechanical properties of samples were measured and the relations between the trace element contents and properties were investigated. (author) 16 refs.; 7 tabs

  17. General discussion about enzymes activities of radiation injury

    Vucicevic, M.; Sukalo, I.

    1989-01-01

    Researching reliable and practical indicators of radiation injury, however, is very interesting and considerable department of scientific studies, practical and theoretical. Enzymes activities are among biochemical indicators which are changed after radiation injury. Activity of these specific proteins is important in regulation of every biochemical reaction in existing beings. Biological macromolecules can be damaged by radiation or the cell permeability can be changed. All of these influence directly on enzymes activities. In this paper we present the review of the all important enzymes, indicators of the radiation injury, which variances on reference to normal values are significant of the functional and the structural changes of essential organs (author)

  18. General discussion about enzymes activities of radiation injury

    Vucicevic, M; Sukalo, I [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)

    1989-07-01

    Researching reliable and practical indicators of radiation injury, however, is very interesting and considerable department of scientific studies, practical and theoretical. Enzymes activities are among biochemical indicators which are changed after radiation injury. Activity of these specific proteins is important in regulation of every biochemical reaction in existing beings. Biological macromolecules can be damaged by radiation or the cell permeability can be changed. All of these influence directly on enzymes activities. In this paper we present the review of the all important enzymes, indicators of the radiation injury, which variances on reference to normal values are significant of the functional and the structural changes of essential organs (author)

  19. μX-ray fluorescence analysis of traces and calcium phosphate phases on tooth-tartar interfaces using synchrotron radiation

    Abraham, J.A.; Grenon, M.S.; Sanchez, H.J.; Valentinuzzi, M.C.; Perez, C.A.

    2007-01-01

    Hard dental tissues like dentine and cementum with calcified deposits (dental calculi) were studied in several human dental pieces of adult individuals from the same geographic region. A couple of cross cuts were performed at dental root level resulting in a planar slice with calculus and dental tissue exposed for analysis. The elemental content along a linear path crossing the dentine-cementum-tartar interfaces and also all over a surface was measured by X-ray fluorescence microanalysis using synchrotron radiation (μSRXRF). The concentration of elemental traces like K, V, Cu, Zn, As, Br and Sr showed different features on the analyzed regions. The possible connections with the dynamic of mineralization and biological implications are discussed. The concentrations of major elements Ca and P were also determined and the measured Ca/P molar ratio was used to estimate the average composition of calcium phosphate phases in the measured points. A deeper knowledge of the variations of the elemental compositions and the changes of the different phases will help to a better understanding of the scarcely known mechanism of calculus growing

  20. Epithermal neutron activation analysis of major and trace elements in Red Sea scleractinian corals

    Abdo, S.Y.; Sherif, M.M.; Frontasyeva, M.V.

    2017-01-01

    Five corals belonging to common scleractinian reef-building species, and collected from Gulf of Suez, Egypt were subjected to neutron activation analysis. The content of 26 elements: Na, Mg, Cl, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Zn, As, Br, Rb, Sr, Sb, I, Cs, Ba, La, Ce, Gd, Hf, Th, and U was experimentally determined. Ca and Sr have the highest content i.e. 38.4-39.5% and 0.73-0.78% respectively while, the content of all other elements was within the ranges reported for the worldwide corals. For a better understanding of the coral exoskeleton elemental content, the partition coefficient calculated for all determined elements showed a wide range of values varying from 2 × 10 -4 in the case of Cl to 2 × 10 3 for Ce and other insoluble elements. Although all corals were collected in the vicinity of the Port Suez no traces of anthropogenic contamination were evidenced. (author)

  1. Study of the trace element content in human cataractous lenses by instrumental neutron activation analysis

    Kouris, T.; Theodossiadis, G.; Papadopoulou, C.; Kanias, G.D.; Baikraktari-Kouri, E.

    1986-01-01

    Cataract is a very common disease of the eye lens known since the ancient times. Different mechanisms are responsible for the biogenesis of cataract but the greater number of scientists agree with the theory that cataract formation can be attributed to metabolism disorders in the lens. Instrumental neutron activation analysis has been applied in this work for the determination of the following trace elements: antimony, cobalt, iron, rubidium, selenium and zinc in human lenses with mature cataract. The obtained results are statistically treated and correlated with age and sex of patients. Based on these findings the concentration of each studied element does not have any correlation with the age and/or sex of the patients i.e. when the lens becomes totally opaque. (author)

  2. Radiochemical neutron activation analysis for trace elements evaluation of human milk

    Gill, K.P.; Zaidi, J.H.; Ahmad, S.

    2003-01-01

    The principal objective pursued in this study is to establish the base-line data on the status of elemental composition in human milk from Pakistani subjects of Rawalpindi/Islamabad area. Radiochemical neutron activation analysis (RNAA) methodology was developed and successfully employed to determine the concentration of 18 minor and trace elements (essential, toxic and nonessential) in human milk. This methodology has significantly improved the detection limits of most of these elements due to suppression of Compton background. The data provide the base-line values of these elements in human milk of low- and medium-income group subjects of the region. The results obtained show good compatibility with the data reported by the WHO on elemental composition of human milk from different geological regions. (orig.)

  3. Determination of trace elements in acid rain by reversed phase extraction chromatography and neutron activation

    Rao, R.R.; Goski, D.G.; Chatt, A.

    1991-01-01

    A preconcentration neutron activation analysis (PNAA) method has been developed for the simultaneous determination of selected trace elements in acid rain and other water samples. The method consists of preconcentration of the elements by reversed phase extraction chromatography using oxine-loaded Amberlite XAD-2 resin. Nearly 100% recoveries were obtained for Co, Cu, Hg, V and Zn at pH 6.0 and for Cd at pH 7.0. Manganese gave incomplete recoveries at the pH range of 4.0-8.0 studies. Various factors that can influence preconcentration of the elements have been investigated in detail. The precision and accuracy of measurements have been evaluated by analyzing certified reference materials. The detection limits have been found to be of the order of ppb. The PNAA method has been applied to a number of acid rain and other water samples

  4. Determination of rare earths and traces of other elements by neutron activation analysis

    Atalla, L.T.; Mantovani, M.S.M.; Marques, L.S.

    A complete methodology for a multielemental analysis in geological material using the neutron activation technique was developed. 21 trace elements (9 of which are rare earths) were determined using thermal and epithermal neutron irradiations. Instrumetnal and radiochemical processing, applied to BCR-1 and G-2 geological standards, are described. Statistical tests carried out on G-2 data show an error smaller than 15% referring to all elements except Cr, Sb and Yb. The observed differences between are discussed. The good precision attained in this method is confirmed by its application to BCR-1 standard, which presents errors smaller than 4% for all elements except Nd, due to its intrinsic properties. The results from the present work are compared with those from other laboratories. (C.L.B.) [pt

  5. Analysis of toxic trace elements in sea food samples by neutron activation

    Sarmani, S.; Majid, A.A.; Wood, A.K.; Hamzah, Z.

    1993-01-01

    The contents of toxic and essential trace element were analysed such as As, Hg, Se and Zn by neutron activation analysis in coastal fishes consumed by the general population of Malaysia. The mean values of the elements analysed expressed in mg/kg fresh weight ranged 1.42-5.61, 0.06-0.42, 4.2-20.6, 0.41-1.28 for As, Hg, Zn and Se, respectively. The maximum permissible limit for As in food was set at 1.0 mg/kg under the Malaysian Food Regulations. The results showed that consumption of coastal fishes is not permitted under the regulations, while the levels of Hg, Se and Zn were within the permissible limits. The daily dietary intake of As and Hg at 400 μg and 30 μg respectively are still within the tolerance levels. (author) 9 refs.; 2 tabs

  6. Trace elements with large activation cross section in concrete materials in Japan

    Suzuki, Atsuo; Iida, Takao; Moriizumi, Jun; Sakuma, Yoichi; Takada, Jitsuya; Yamasaki, Keizo; Yoshimoto, Takaaki

    2001-01-01

    Amounts of trace elements with large activation cross section in concrete materials were measured to offer the basic data for developing of low activation concrete. From the measurements, the quantities of the activated radioactivities in biological shielding concrete were measured and evaluated for the clearance level. The average concentrations of 60 Co, 152 Eu and 134 Cs formed in concrete were 21.9, 1.08 and 3.21 ppm, respectively. The combination of the concrete materials for the most lowering concentrations of 60 Co, 152 Eu and 134 Cs was the limestone as aggregate and the white Portland cement produced in specific places. The most lowering concentrations of this limestone concrete were 0.16, 0.049 and 0.060 ppm, respectively. The limestone concrete was excellent as biological shielding concrete, because the neutron shielding effect was excellent a little compared with ordinary concrete. If this concrete used for biological shielding concrete, concrete waste will be able to handle as follows. Usage of this limestone low-activated concrete makes almost all concretes satisfy the clearance level for 60 Co after 20 yr cooling from decommissioning. In respect of 152 Eu, radioactivation quantity in the biological shielding concrete is reduced up to a half of the average value or less. With regard to 134 Cs, all concrete satisfies the clearance level. (author)

  7. Magnetic Characteristics of Active Region Heating Observed with TRACE, SOHO/EIT, and Yohkoh/SXT

    Porter, J. G.; Falconer, D. A.; Moore, R. L.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    Over the past several years, we have reported results from studies that have compared the magnetic structure and heating of the transition region and corona (both in active regions and in the quiet Sun) by combining X-ray and EUV images from Yohkoh and Solar and Heliospheric Observatory (SOHO) with photospheric magnetograms from ground-based observatories. Our findings have led us to the hypothesis that most heating throughout the corona is driven from near and below the base of the corona by eruptive microflares occurring in compact low-lying "core magnetic fields (i.e., fields rooted along and closely enveloping polarity inversion lines in the photospheric magnetic flux). We now extend these studies, comparing sequences of UV images from Transition Region and Coronal Explorer (TRACE) with longitudinal magnetograms from Kitt Peak and vector magnetograms from MUSIC. These comparisons confirm the previous results regarding the importance of core-field activity to active region heating. Activity in fields associated with satellite polarity inclusions and/or magnetically sheared configurations is especially prominent. This work is funded by NASA's Office of Space Science through the Sun-Earth Connection Guest Investigator Program and the Solar Physics Supporting Research and Technology Program.

  8. Guidance on radiation received in space activities

    1989-01-01

    The purposes of this report, therefore, are to: re-examine the current guidelines and the philosophy adopted by NASA, estimate the risks to both men and women exposed to radiation in space, re-examine the estimates of radiation risks in outer space with special attention to SPE and to exposure to HZE particles, and examine what information may still be required and what research is needed. This report incorporates the changes in estimates of terrestrial radiation risks made since 1970 that appear to be acceptable and appropriate to the particular case of space missions. Since plans for a space station have been established and are a priority for NASA, this space mission will be used as one example for reference. The likely altitude and orbit for the proposed space station are 450 km and 28.5 degree, respectively. Therefore, estimates of the radiation environment for this mission can be made with more confidence than for some of the other missions. In this report, we have chosen to write more fully about certain subjects, for example, the eye, because they are of concern and because they have not been dealt with in such detail in other reports on radiation risks and protection. Since this report covers a number of different disciplines and specialized areas of research, a glossary is included. Radiation protection in space is as international a task as is the protection of radiation workers and the general population on earth. Kovalev, 1983, has noted that radiation protection in space is a pressing but complex problem. The recommendations in this report will require modifications as we learn more about the radiation environment in space and how to estimate radiation risks with greater precision. 450 refs

  9. Determination of trace elements in total particulate matter of cigarette smoke by instrumental neutron activation analysis

    Mishra, U.C.; Shaikh, G.N.

    1985-01-01

    Cigarette smoke contains many trace elements hazardous for human body. Tobacco samples were analyzed for their trace element contents and the results were reported earlier. This paper presents results on the trace element content analyzed in cigarette smoke using an automatic smoking machine developed in laboratory to simulate actual smoking pattern. The trace element levels in the total particulate matter samples of the cigarette smoke collected on filter papers were measured and compared with those of cigarette smoke condensate reported in the literature. Both methods of collection give comparable results. (author)

  10. Determination of trace elements in Turkish tea leaves by instrumental neutron activation analysis

    Demiralp, R.

    1986-01-01

    The human body continuously assimilates a variety of inorganic elements from food and the environment. Some of these elements are closely related to human health and disorder. Tea is one of the most popular stimulating beverages which is consumed by low and high income family groups in many countries. Instrumental neutron activation analysis is one of the preferred methods because information on a large number of elements can be obtained simultaneously. Five packets each of the seven commonly used brands of tea were obtained from the market. In order to determine the transfer of trace elements into the drinkable portion about 2-3g. of the tea leaves were boiled in hot water for 2 min. After filtration the used tea leaves were dried at 65 deg. C in an oven and a portion, about 200mg was used for analysis. Samples and standards were irradiated 10 min. and 2 hrs. at pneumatic system and central thimble in the TRIGA MARK-II research reactor. After irradiation, the activities of samples and standards were measured with a aoaxial Ge detector coupled to a spectroscopic amplifier. A Canbera 90 model multi- channel analyzer with an 8K memory was used for pulse height analysis. The system has a resolution of 2.0 KeV. for the 1332.5 KeV gamma ray of 60 Co. The activity of the sample and standard was compared and the element contst of the sample was calculated. (author)

  11. Determination of minor-and trace elements in magnesite samples, by activation analysis

    Sepulveda Munita, C.J.A.

    1979-01-01

    A method employing activation analysis with thermal neutron was developed for the determination of minor and trace elements in magnesite samples from the states of Ceara and Bahia (Brazil). Ten samples were analyzed. A qualitative analysis of the samples indicated the presence of Mn, Fe, Sc, Ca, Cu, Co and some of the lanthanides. The experimental part includes a non-destructive analysis of manganese and analysis with chemical separation of the other elements, individually or in groups, after sample dissolution, The dissolutions were made with concentrated HCl and the further separations were carried out in 8 N HCl medium. Iron was separated by means of an extraction of HFeCl 4 with isopropyl ether. Scandium and calcium were determined by retention of scandium with di-(2-ehylhexyl) phosphoric acid (HDEHP). The activities of 46 Sc and 47 Sc (a 47 Ca descendant) were employed for the analysis of scandium and calcium in the sample. In the effluent of the kieselguhr column copper and cobalt were determined, after retention in an anionic resin of the CuCl - 3 and CoCl - 3 complexes. Finally, in the effluent of the resin, the lanthanide group was separated by oxalate precipitation. In the gamma-ray spectrum of this precipitate the elements europium, cerium, samarium and lanthanum were determined. A detailed study of the possible interferences in the neutron activation analysis of the elements analysed was also made. The precision and accuracy of the results obtained and the sensitivity of the method are discussed. (Author) [pt

  12. Alkaline phosphatase activity in the subtropical ocean: insights from nutrient, dust and trace metal addition experiments

    Claire eMahaffey

    2014-12-01

    Full Text Available Phosphorus is an essential nutrient for all life on earth. In the ocean, the most bioavailable form of phosphorus is inorganic phosphate, but in the extensive subtropical gyres, phosphate concentrations can be chronically low and limit primary productivity and nitrogen fixation. In these regions, organisms produce hydrolytic enzymes, such as alkaline phosphatase (AP, that enable them to utilize the more replete dissolved organic phosphorus (DOP pool to meet their cellular phosphorus demands. In this study, we synthesized data from 14 published studies and present our own findings from two research cruises (D326 and D361 in the eastern subtropical Atlantic to explore the relationship between AP activity (APA and nutrients, Saharan dust and trace metals. We found that below a threshold phosphate concentration of ~ 30 nM, APA increased with an inverse hyperbolic relationship with phosphate concentration. Meanwhile, DOP concentrations decreased with enhanced APA, indicating utilization of the DOP pool. We found APA rates were significantly higher in the subtropical Atlantic compared to the subtropical Pacific Ocean, even over the same low phosphate concentration range (0 to 50 nM. While the phosphate concentration may have a first order control on the APA rates, we speculate that other factors influence this basin scale contrast. Using bioassay experiments, we show that the addition of Saharan dust and zinc significantly increased the rate of APA. To our knowledge, our results are the first direct field-based evidence that APA is limited by zinc in the subtropical ocean. Further work is required to explore the relationship between trace metals such as iron and zinc, which are co-factors of phosphohydrolytic enzymes, specifically PhoX and PhoA, respectively, and APA in the ocean.

  13. Influence of 2. 45 GHz microwave radiation on enzyme activity

    Galvin, M J; Parks, D L; McRee, D I

    1981-05-01

    The in vitro activity of acetylcholinesterase and creatine phosphokinase was determined during in vitro exposure to 2.45 GHz microwave radiation. The enzyme activities were examined during exposure to microwave radiation at specific absorption rates (SAR) of 1, 10, 50, and 100 mW/g. These specific absorption rates had no effect on the activity of either enzyme when the temperature of the control and exposed samples were similar. These data demonstrate that the activity of these two enzymes is not affected by microwave radiation at the SARs and frequency employed in this study.

  14. The regeneration of polluted active carbon by radiation techniques

    Bao Borong; Wu Minghong; Hu Longxin; Zhou Riumin; Zhu Jinliang

    1998-01-01

    In this paper, we investigated the regeneration of polluted active carbon from monosodium glutamate factory by combination of radiation and acid-alkali chemical techniques. The experimental results show that the polluted active carbon will be highly regenerated on the conditions of process concentration 3%, process time 0.5 hour and the adjustment process concentration 2%, time 0.5 hour, radiation dose 5kGy. As regeneration times increase, the regenerated active carbon behaves with good repetition and stable property

  15. Santos estuarine sediments, Brazil - metal and trace element assessment by neutron activation analysis

    Amorim, Eduardo P.; Favaro, Deborah I.T.; Berbel, Glaucia; Braga, Elisabete S.

    2009-01-01

    The Santos estuary system is an intricate pattern of tidal channels and small rivers originating from the adjacent Pre-Cambrian slopes. These two major estuaries share a common area in the upper portion of the region which interacts with each other. The largest harbor in Latin America is located at the eastern outlet of the Santos estuary. This intricate and sensitive ecosystem is highly susceptible to human impact from industrial activities, urban sewage and polluted solid wastes disposal. Due to its high vulnerability CETESB (Environmental Control Agency of the Sao Paulo State) sporadically monitors the contamination levels of water, sediment and marine organisms in this region. The present study reports results concerning the distribution of some major, trace and rare earth elements in the Santos estuarine marine sediments. Thirty two bottom sediment samples (SS0601 to SS0616 (summer) and SW0601 to SW0616 (winter) were collected in this estuary, including regions of Sao Vicente, Santos, Cubatao and Vicente de Carvalho, by a vanVeen sampler in the summer and winter of 2006. Multielemental analysis was carried out by instrumental neutron activation analysis (INAA). The concentration values obtained for As and metals Cr and Zn in the sediment samples were compared to Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL values) and are adopted by CETESB. (author)

  16. Santos estuarine sediments, Brazil - metal and trace element assessment by neutron activation analysis

    Amorim, Eduardo P.; Favaro, Deborah I.T., E-mail: ducamorim@yahoo.com.b, E-mail: defavaro@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP) Sao Paulo, SP (Brazil); Berbel, Glaucia; Braga, Elisabete S., E-mail: edsbraga@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Inst. Oceanografico. Lab. de Nutrientes, Micronutrientes e Tracos nos Oceanos (LABNUT)

    2009-07-01

    The Santos estuary system is an intricate pattern of tidal channels and small rivers originating from the adjacent Pre-Cambrian slopes. These two major estuaries share a common area in the upper portion of the region which interacts with each other. The largest harbor in Latin America is located at the eastern outlet of the Santos estuary. This intricate and sensitive ecosystem is highly susceptible to human impact from industrial activities, urban sewage and polluted solid wastes disposal. Due to its high vulnerability CETESB (Environmental Control Agency of the Sao Paulo State) sporadically monitors the contamination levels of water, sediment and marine organisms in this region. The present study reports results concerning the distribution of some major, trace and rare earth elements in the Santos estuarine marine sediments. Thirty two bottom sediment samples (SS0601 to SS0616 (summer) and SW0601 to SW0616 (winter) were collected in this estuary, including regions of Sao Vicente, Santos, Cubatao and Vicente de Carvalho, by a vanVeen sampler in the summer and winter of 2006. Multielemental analysis was carried out by instrumental neutron activation analysis (INAA). The concentration values obtained for As and metals Cr and Zn in the sediment samples were compared to Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL values) and are adopted by CETESB. (author)

  17. Soil pollution with trace elements at selected sites in Romania studied by instrumental neutron activation analysis

    Pantelica, A.; Carmo Freitas, M. do; Ene, A.; Steinnes, E.

    2013-01-01

    Instrumental neutron activation analysis (INAA) was used to determine concentrations of 42 elements in samples of surface soil collected at seven sites polluted from various anthropogenic activities and a control site in a relatively clean area. Elements studied were Ag, Al, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Eu, Fe, Gd, Hf, Hg, K, La, Lu, Mg, Mn, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, U, V, W, Yb, Zn, and Zr. The results are compared with data for trace elements atmospheric deposition in lichen transplants from the same sites. The most severe soil contamination was observed at Copsa Mica from non-ferrous metallurgy. Appreciable soil contamination was also indicated at Baia Mare (non-ferrous mining and metallurgy), Deva (coal-fired power plant, cement and building materials industry), Galati (ferrous metallurgy), Magurele and Afumati (general urban pollution), and Oradea (chemical and light industries). In most cases excessive levels of toxic metals in soils matched correspondingly high values in lichen transplants. Compared to Romanian norms, legal upper limits were exceeded for Zn and Cd at Copsa Mica. Also, As and Sb occurred in excessive levels at given sites. (orig.)

  18. Soil pollution with trace elements at selected sites in Romania studied by instrumental neutron activation analysis

    Pantelica, A. [Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH), Magurele, Ilfov County (Romania); Carmo Freitas, M. do [Technological and Nuclear Institute (ITN), Sacavem (Portugal); Ene, A. [Dunarea de Jos Univ. of Galati (Romania). Dept. of Chemistry, Physics and Environment; Steinnes, E. [Norwegian Univ. of Science and Technology, Trondheim (Norway). Dept. of Chemistry

    2013-03-01

    Instrumental neutron activation analysis (INAA) was used to determine concentrations of 42 elements in samples of surface soil collected at seven sites polluted from various anthropogenic activities and a control site in a relatively clean area. Elements studied were Ag, Al, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Eu, Fe, Gd, Hf, Hg, K, La, Lu, Mg, Mn, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, U, V, W, Yb, Zn, and Zr. The results are compared with data for trace elements atmospheric deposition in lichen transplants from the same sites. The most severe soil contamination was observed at Copsa Mica from non-ferrous metallurgy. Appreciable soil contamination was also indicated at Baia Mare (non-ferrous mining and metallurgy), Deva (coal-fired power plant, cement and building materials industry), Galati (ferrous metallurgy), Magurele and Afumati (general urban pollution), and Oradea (chemical and light industries). In most cases excessive levels of toxic metals in soils matched correspondingly high values in lichen transplants. Compared to Romanian norms, legal upper limits were exceeded for Zn and Cd at Copsa Mica. Also, As and Sb occurred in excessive levels at given sites. (orig.)

  19. Intercomparison and determination of trace elements in urban dust by neutron activation analysis

    Chung, Yong Sam; Moon, Jong Hwa; Kim, Sun Ha; Park, Kwang Won; Kang, Sang Hun

    2000-01-01

    Trace elements in air samples artificially loaded on filters with urban dust and the bulk material of urban dust as an environmental sample were determined non-destructively using instrumental neutron activation analysis. Standard reference material (Urban Dust, SRM 1648) of the National Institute of Standard and Technology was used for the analytical quality control. The relative error for 37 elements was less than 15% and the standard deviation was less than 10%. 29 elements in the urban dust and 21 elements in the loaded filter sample were determined respectively. To evaluate the proficiency and reliability of the measurement, data intercomparison was performed and 39 analytical laboratories participated in the analysis using different analytical methods; neutron activation analysis, particle induced X-ray emission analysis, X-ray fluorescence analysis and atomic absorption spectrometry. Z-scores were calculated using the standard deviation of the laboratory's mean as target standard deviation, and a good result was obtained that the values fall between-1 and +1 except some elements. (author)

  20. Determination of trace elements in fisheries samples by instrumental neutron and photon activation analysis

    Chattopadhyay, A.; Ellis, K.M.; Nimalasiri Desilva, K.

    1979-01-01

    An instrumental neutron activation analysis (INAA) method has been developed for the simultaneous determination of trace concentrations of up to 23 elements in fisheries samples. The INAA method consists of irradiations of wet and lyophilized cod muscle and liver samples for three different periods at a flux density of 5x10 11 n.cm -2 .s -1 and subsequent measurements after four different decay periods using high-resolution Ge(Li) gamma-ray spectrometry. Concentrations of several essential and toxic elements have been determined. Loss of certain elements during lyophilization has been studied. Elemental distribution in muscles and livers as a function of the age of fish has been investigated. Precision and accuracy of the INAA method have been evaluated by analysing replicate samples, National Bureau of Standards' bovine liver standard reference material, and an intercalibration fish flour sample provided by the International Council for the Exploration of the Sea. A few fish samples have also been analysed by an alternative method, namely instrumental photon activation analysis (IPAA). Elemental concentrations determined by both INAA and IPAA methods are reported here. (author)

  1. Trace cobalt speciation in bacteria and at enzymic active sites using emission Moessbauer spectroscopy

    Kamnev, A.A.; Antonyuk, L.P.; Smirnova, V.E.; Serebrennikova, O.B. [Laboratory of Biochemistry, Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, Saratov (Russian Federation); Kulikov, L.A.; Perfiliev, Yu.D. [Laboratory of Nuclear Chemistry Techniques, Department of Radiochemistry, Faculty of Chemistry, Moscow State University (Russian Federation)

    2002-02-01

    {sup 57}Co emission Moessbauer spectroscopy (EMS) allows the chemical state of cobalt, as influenced by its coordination environment, to be monitored in biological samples at its physiological (trace) concentrations. To draw attention to EMS as a valuable tool for speciation of cobalt in biocomplexes, the process of cobalt(II) metabolism in cells of the plant growth-promoting rhizobacterium Azospirillum brasilense Sp245 was investigated using EMS of {sup 57}Co{sup II}-doped bacterial cells. EMS measurements also showed {sup 57}Co{sup II}-activated glutamine synthetase (GS, a key enzyme of nitrogen metabolism, isolated from this bacterium) to have two different cobalt(II) forms at its active sites, in agreement with data available on other bacterial GSs. Chemical after-effects following electron capture by the nucleus of the parent {sup 57}Co{sup II} during the {sup 57}Co{yields}{sup 57}Fe transition, which contribute to the formation of a stabilised daughter {sup 57}Fe{sup III} component along with the nucleogenic {sup 57}Fe{sup II} forms, are also briefly considered. (orig.)

  2. Research for Actively Reducing Infrared Radiation by Thermoelectric Refrigerator

    Kim, Hoon; Kim, Kyomin; Kim, Woochul [Yonsei Univ., Seoul (Korea, Republic of)

    2017-03-15

    We introduced a technology for reducing infrared radiation through the active cooling of hot surfaces by using a thermoelectric refrigerator. Certain surfaces were heated by aerodynamic heating, and the heat generation processes are proposed here. We calculated the temperatures and radiations from surfaces, while using thermoelectric refrigerators to cool the surfaces. The results showed that the contrast between the radiations of certain surfaces and the ambient environments can be removed using thermoelectric refrigerators.

  3. Regional and national radiation protection activities in Egypt

    Gomaa, M.A.M.

    2008-01-01

    Radiation protection activities in Egypt go back to 1957 where the Egyptian Atomic Energy Commission (EAEC) Law was issued. Radiation protection and civil defense department was one of EAEC eighth departments. Ionizing radiation law was issued in 1960 and its executive regulation in 1962. The main aim of the present work is to through some light on the current radiation protection activities in Egypt. This includes not only the role of governmental organizations but also to the non governmental organizations. Currently a new Nuclear Safety law is understudy. Regional activities such as holding the second all African IRPA regional radiation protection congress which was held in April 2007 and national training and workshops are held regularly through EAEA, AAEA and MERRCAC. (author)

  4. Use of neutron activation analysis to measure the variation in trace element concentrations in a coal seam

    Fardy, J.J.; Swaine, D.J.

    1985-01-01

    Trace element concentrations were measured by neutron activation on 57 run-of-mine coal samples from several locations in seven mines located in the Lithgow seam in the Western Coalfield, Sydney Basin. Results were tabulated as ratios of the highest to the lowest variance for each element

  5. Internal standard method for determination of gallium and some trace elements in bauxite by neutron activation analysis

    Chen, S.G.; Tsai, H.T.

    1983-01-01

    A method is described for the determination of gallium and other trace elements such as Ce, Cr, Hf, Lu and Th in bauxite by the technique of neutron activation analysis using gold as internal standard. Isopropyl ether was used as organic extractant radioactive gallium from the sample. This method yields very good accuracy with a relative error of +-3%. (author)

  6. Determination of natural radioactive elements in building materials by gamma spectroscopy, trace dosimetry and neutron activation analysis

    Perez, G.; Desdin, L.F.; Hernandez, A.T.; Gonzalez, D.; Labrada, A.; Tenreiro, J.J.; Capote, G.; Perelyguin, V.P.; Herrera, H.; Tellez, E.

    1993-01-01

    Five types of Cuban concretes and their main components (minerals aggregates and cement) were investigated in order to analyze the content of uranium, thorium, radium, potassium and radon 220,222, using gamma spectroscopy, trace dosimetry and neutron activation analysis. The comparative evaluation of different concretes, aggregates and two types of cements according to natural radioactivity is shown

  7. Trace element determination study in human hair by neutron activation analysis

    Frazao, Selma Violato

    2008-01-01

    Human hair analysis studies have been subject of continuous interest due to the fact that they can be used as an important tool to evaluate trace element levels in the human body. These determinations have been carried out to use hair for environmental and occupational monitoring, to identify intoxication or poisoning by toxic metals, to assess nutritional status, to diagnose and to prevent diseases and in forensic sciences. Although hair analysis presents several advantages over other human tissue or fluid analyses, such as organ tissue, blood, urine and saliva, there are some controversies regarding the use of hair analysis data. These controversies arise from the fact that it is difficult to establish reliable reference values for trace elements in hair. The purpose of this study was to evaluate the factors that affect element concentrations in hair samples from a population considered healthy and residing in the Sao Paulo metropolitan area. The collected human head hair was cut in small pieces, washed, dried and analyzed by neutron activation analysis (NAA). Aliquots of hair samples and synthetic elemental standards were irradiated at the IEA-R1 nuclear research reactor for 16 h under a thermal neutron flux of about 5x10 12 n cm -2 s -1 for As, Br, Ca, Co, Cr, Cs, Cu, Fe, K, La, Na, Sb, Sc, Se and Zn determinations. The induced gamma activities of the standards and samples were measured using a gamma ray spectrometer coupled to an hiperpure Ge detector. For quality control of the results, IAEA- 85 Human Hair and INCT-TL-1 Tea Leaves certified reference materials (CRMs) were analyzed. Results obtained in these CRMs presented for most of elements, good agreement with the values of the certificates (relative errors less than 10%) and good precision (variation coefficients less than 13.6%). Results of replicate hair sample analysis showed good reproducibility indicating homogeneity of the prepared sample. Results obtained in the analyses of dyed and non-dyed hair

  8. Alteration of yeast activity by gamma radiation

    Chacharkar, M.P.; Tak, B.B.; Bhati, J.

    1996-01-01

    Yeast is an important component in microbe based industrial technologies. Due to the techno-economic reasons, the fermentation technique has acquired renewed interest. The effect of γ-radiation on the fermentation reaction has been investigated. The studies show that exposure of the fermentation mixture to γ-radiation at 5 kGy enhance alcohol production, whereas irradiation at higher doses, viz., 10 kGy and 25 kGy caused a considerable reduction in the alcohol yield. Therefore, low dose irradiation of fermentation mixtures can be applied for increasing the alcohol production by about 25%. (author). 13 refs., 1 fig

  9. The radiation protection programme activities of the World Health Organization

    Komarov, E.; Suess, M.J.

    1980-01-01

    The radiation protection activities of the World Health Organization are reviewed. They include studies of radiation protection standards and guidelines, and public health aspects of nuclear power. WHO also provides member states with world data on radioactivity in air, water and food, and assessments of population exposure and health effects. (H.K.)

  10. Application of neutron activation analysis to the development of a monitoring system for trace metals in coastal waters

    Karbe, L.; Schnier, C.

    1976-03-01

    In view of the development of monitoring systems for trace metals in coastal waters, a research program has been started for a better understanding of interrelationships between input of trace metals, water chemistry, suspended matter, sediment and organisms. For multielement determinations neutron activation analysis has been chosen. Since environmental studies require the analysis of a large number of samples, the efficiency of the method is improved by automation of the acquisition and analysis of the γ-spectra from the Ge(Li) detectors. An automatic sample changer with counting device is described. First applications of the method in environmental research are presented. (orig.) [de

  11. Trace element determination in fingernails, hair and blood serum in patients with Crohn's disease using neutron activation analysis

    Buschmann, H.

    1984-01-01

    The determination of trace elements and electrolyte concentrations in blood serum, hair and fingernails of 16 patients with Crohn's disease was carried out by means of instrumental neutron activation analysis. In the serum a significant decline in the zinc content could be registered, while the remaining trace elements remained in the normal range. The parenteral nutrition also showed a zinc deficiency. There was, however, also an iron deficiency. The studies of the hair and fingernails gave the following results: Rubidium and antimony in the normal range; zinc, selenium, iron and cobalt below normal values. (orig./PW) [de

  12. Some trace elements in the waters, marine organisms and sediments of the Adriatic by neutron activation analysis

    Kosta, L.; Ravnik, V.; Byrne, A.R.; Dermelj, M.; Stirn, J.

    1978-01-01

    A number of investigations of trace elements in the waters, organisms and sediments of the Adriatic, using neutron activation analysis with radiochemical separations are reported. These include studies of Hg in mussels from the Northern Adriatic, of Hg and Se in edible animals from the Rijeka region, and of seven elements (As, Cd, Cu, Hg, Mn, Se and Zn) in marine invertebrates from the Slovene coast. Additionally, plankton, sediment cores and water samples were taken from a grid of stations covering the whole Adriatic and analyzed for 6 to 11 of the trace elements As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Sb and Zn (Hg only in water). Generally, levels found were not indicative of pollution as compared with oceanic samples, but some evidence of locally increased levels was found, especially for Hg. The levels of eleven trace elements in three marine Intercomparison samples prepared by the IAEA Monaco Laboratory are also presented. (T.G.)

  13. Determination of trace elements in soil and plants in the Orontes basin of Syria by using instrumental neutron activation analysis

    Kassem, A.; Sarheel, A.; Al-Somel, N.

    2004-01-01

    Instrumental neutron activation analysis (INAA) have been used for the determination of some major, minor and trace elements (As, Cr, Co, Ni, Zn, Sb, Sc, Ce, Ti, Fe, Mn and V) in various plant leaves together with their soil. The accuracy of the measurements have been evaluated by analyzing a number of plant and soil reference materials, precision have been estimated by triplicate analysis of the sample as well as that of the reference material. The obtained accurate and reliable data of some trace elements on microgram level for plants and soil will serve as baseline values and will be helpful to monitor the changes in the trace element content of soil and plant leaves. (author)

  14. Bags with oven-dried moss for the active monitoring of airborne trace elements in urban areas

    Giordano, S.; Adamo, P.; Monaci, F.; Pittao, E.; Tretiach, M.; Bargagli, R.

    2009-01-01

    To define a harmonized methodology for the use of moss and lichen bags as active monitoring devices of airborne trace elements in urban areas, we evaluated the element accumulation in bags exposed in Naples in different spring weather conditions for 6- and 12-weeks. Three different pre-exposure treatments were applied to moss and lichen materials: water-washing, acid-washing and oven-drying. During the different exposure periods in the Naples urban environment the moss accumulated always higher amounts of elements (except Hg) than lichens and the element accumulation increased during wetter weather and higher PM 10 conditions. The oven pre-treatment did not substantially modify the morphology and element composition of moss and the exposure in bags of this material for 6-weeks was sufficient to detect the pattern of airborne trace elements. - A 6-week exposure with oven-dried moss bags resulted a suitable approach to evaluate airborne trace elements in a Mediterranean urban environment.

  15. Determination of trace elements in tea leaves by neutron activation analysis

    Kasrai, M.; Shoushtarian, M.J.; Bozorgzadeh, M.H.

    1977-01-01

    Instrumental neutron-activation analysis has been employed to determine 14 trace elements in two brands of Iranian and foreign tea. A popular local brand (Ghoncheh) and a foreign brand (Lipton tea bags) were randomly purchased. The samples were dried in an oven (100 deg C) and used without further treatment. In order to measure the concentration of elements in tea solution, weighed amounts of tea were mixed with double-distilled boiling water. After cooling the leaves were separated by centrifugation. Aliquots of clear solution were dried for analysis. Three sets of standards containing the following elements using the spec-pure materials were prepared: (a) Cl, Mn, Na, K; (b) Br, La, Au; (c) Cr, Fe, Rb, Sc, Cs, Zn, Co. In each irradiation, one set of standards, along with the sample, was neutron irradiated at a thermal flux of approximately 2x10 13 ncm -2 sec -1 in the Research Reactor of the Nuclear Research Centre. The period of irradiation ranged from 10 min to 4 hrs, depending on the radionuclides to be measured. The transference ratio of the elements into solution, when tea is leached by percolation, is also reported. It was found that some elements are totally transferred into solution and some are partially retained by the leaves. (T.G.)

  16. Major and trace elements assessment in sediment from Ituparanga reservoir, by activation analysis and ICP OES

    Silva, Sharlleny A., E-mail: sharllenya@cetesbnet.sp.gov.br [Companhia de Tecnologia de Saneamento Ambiental (CETESB), Sao Paulo, SP (Brazil). Lab. de Quimica Inorganica; Bevilacqua, Jose Eduardo [Companhia de Tecnologia de Saneamento Ambiental (CETESB), Sao Paulo, SP (Brazil). Diretoria de Tecnologia, Qualidade e Avaliacao Ambiental; Favaro, Deborah I.T., E-mail: defavaro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Lab. de Analise por Ativacao Neutronica

    2011-07-01

    The Ituparanga reservoir was built to generate electric power by the LIGHT Company and started its operation in 1912. It is fed by the Una, Sorocamirim and Sorocabucu rivers. This reservoir supplies water to a population of 600.000. This water system is affected by irregular soil occupation and urban development which has caught CETESB's (Environmental Company of Sao Paulo State) attention. In this study four geo-referenced sampling points were used and bottom sediment samples were collected. The sediment samples were dried at 400 deg C, ground in an agate mortar, sieved (200 mesh) and again homogenized. The instrumental neutron activation analysis was applied to the sediment samples in order to determine some major elements (Fe, K and Na), trace (As, Ba, Br, Co, Cr, Cs, Hf, Rb, Sb, Sc, Ta, Tb, Th, U and Zn) and rare earth (Ce, Eu, La, Lu, Nd, Sm, Tb and Yb) elements. By using ICP OES metals determination for Cd, Cr, Cu, Pb and Ni was undertaken after digestion procedure according to the 3051 method from US EPA. The methodology validation for precision and accuracy was carried out by reference material analyses. For metals Cd, Cr, Cu, Pb and Ni the concentration values were compared to the oriented values from Environmental Canada (TEL and PEL). The Enrichment Factor (EF) was calculated for sediment contamination assessment. (author)

  17. Activation analysis of trace amounts of rare earth in high purity tantalum

    Ishibashi, Wataru; Saito, Shinichi; Hirayama, Tooru.

    1975-01-01

    It is necessary to separate rare earth from tantalum by rapid methods in order to remove effects of a strong radioactivity and a short half-life. Tantalum is extracted with 10%N-lauryl (trialkylmethyl) amino-benzene pre-equilibrated with a solution of 9 M hydrochloric and 0.15 M hydrofluoric acid. A non-radioactive rare earth element is added to this aqueous solution, a precipitate of trace amounts of radioactive rare earth in aqueous solution is formed by this addition of rare earth. Some factors in the determination are: 1) the effect of the irradiation position of the sample in the atomic reactor, 2) the effect on the extraction with 10%N-lauryl (trialkylmethyl) amino-benzene for the radioactive rare earth, 3) the effect of the concentration of hydrofluoric acid, ammonia water and nitric acid on co-precipitation. As a result of the investigation we obtained the following satisfactory results: 1) Rare earth was not effected by the extraction of tantalum with 10%N-lauryl (trialkylmethyl) amino-benzene. 2) The recovery of rare earth by co-precipitation increases when an ammonium ion coexists, and when the concentration of hydrofluoric acid decreases, but the recovery decreases with the increase of nitric acid concentration. 3) The time required for the extraction is 9 hours. In case of determination for dysprosium, tantalum extracted with 10%N-lauryl (trialkylmethyl) amino-benzene before activation and the time for separation is 2 hours. (auth.)

  18. Quantitative Structure--Activity Relationship (QSAR) for the Oxidation of Trace Organic Contaminants by Sulfate Radical.

    Xiao, Ruiyang; Ye, Tiantian; Wei, Zongsu; Luo, Shuang; Yang, Zhihui; Spinney, Richard

    2015-11-17

    The sulfate radical anion (SO4•–) based oxidation of trace organic contaminants (TrOCs) has recently received great attention due to its high reactivity and low selectivity. In this study, a meta-analysis was conducted to better understand the role of functional groups on the reactivity between SO4•– and TrOCs. The results indicate that compounds in which electron transfer and addition channels dominate tend to exhibit a faster second-order rate constants (kSO4•–) than that of H–atom abstraction, corroborating the SO4•– reactivity and mechanisms observed in the individual studies. Then, a quantitative structure activity relationship (QSAR) model was developed using a sequential approach with constitutional, geometrical, electrostatic, and quantum chemical descriptors. Two descriptors, ELUMO and EHOMO energy gap (ELUMO–EHOMO) and the ratio of oxygen atoms to carbon atoms (#O:C), were found to mechanistically and statistically affect kSO4•– to a great extent with the standardized QSAR model: ln kSO4•– = 26.8–3.97 × #O:C – 0.746 × (ELUMO–EHOMO). In addition, the correlation analysis indicates that there is no dominant reaction channel for SO4•– reactions with various structurally diverse compounds. Our QSAR model provides a robust predictive tool for estimating emerging micropollutants removal using SO4•– during wastewater treatment processes.

  19. Sample handling and chemical procedures for efficacious trace analysis of urine by neutron activation analysis

    Blotcky, A.J.; Rack, E.P.; Roman, F.R.

    1988-01-01

    Important for the determination of trace elements, ions, or compounds in urine by chemical neutron activation analysis is the optimization of sample handling, preirradiation chemistry, and radioassay procedures necessary for viable analysis. Each element, because of its natural abundance in the earth's crust and, hence, its potential for reagent and environmental contamination, requires specific procedures for storage, handling, and preirradiation chemistry. Radioassay techniques for radionuclides vary depending on their half-lives and decay characteristics. Described in this paper are optimized procedures for aluminum and selenium. While 28 Al (T 1/2 = 2.24 min) and 77m Se(T 1/2 = 17.4s) have short half-lives, their gamma-ray spectra are quite different. Aluminum-28 decays by a 1779-keV gamma and 77m Se by a 162-keV gamma. Unlike selenium, aluminum is a ubiquitous element in the environment requiring special handling to minimize contamination in all phases of its analytical determination

  20. Fate of Trace Organic Compounds in Granular Activated Carbon (GAC Adsorbers for Drinking Water Treatment

    Alexander Sperlich

    2017-06-01

    Full Text Available Granular activated carbon (GAC adsorbers for drinking water treatment were operated for approx. 14 months and the breakthrough of dissolved organic carbon (DOC and trace organic chemicals (TOrCs was monitored. Effluent concentration profiles of gabapentin and valsartan acid increase already at throughputs of <10,000 BV. The corresponding breakthrough curves flatten out without reaching the influent concentration level. This strongly indicates biological degradation of these substances in the GAC adsorbers under aerobic conditions, contributing to a more efficient use of GAC. The observed biodegradation in pilot GAC adsorbers also confirms recent reports of biodegradation of gabapentin and valsartan acid during managed aquifer recharge. Oxypurinol is comparatively well adsorbed and no breakthrough was observed during the experimental period. Adsorption capacity and breakthrough characteristics of oxypurinol appear very similar to carbamazepine. Breakthrough of GAC adsorbers operated with drinking water was compared to those of groundwater-fed adsorbers. The results show, that it is generally advisable to use previously aerated influents for GAC fixed-bed adsorbers because this can substantially improve biological removal of otherwise poorly adsorbable compounds and ensure full GAC accessibility for adsorbates by avoiding the undesirable formation of inorganic precipitates on adsorption sites.

  1. Instrumental Neutron Activation Analysis of Trace Elements in Some Food Spices Consumed In Tehran, Iran

    ali asghar fathivand

    2017-03-01

    Full Text Available Introduction There is a growing interest in determining the concentration of various elements in food spices. In the present study, the instrumental neutron activation analysis (INAA was employed to measure the trace elements in 11 commonly food spices consumed in Tehran, Iran. Materials and Methods The levels of K, Mn, Na, Cl, V, Br, Al, and As were determined and their effects on human health were discussed. The results were compared with the values reported in the literature. The accuracy and precision of the analytical procedure was estimated by analyzing the Lichen (IAEA-336 reference material. Results The concentrations of the measured elements in the spices were 3850-29157, 10-335, 153-2849, 186-3063, 0.2-2.8, 2.1-58.7, and 72-2102 ppm for K, Mn, Na, Cl, V, Br, and Al, respectively. As was only detected in thyme (0.8 ppm and plantain (0.42 ppm. Conclusion As the findings of the present study indicated, the concentrations of K and Na in the black pepper, garlic, and ginger were significantly higher than the values reported in other countries. The Mn levels in the black pepper and garlic consumed in Tehran were comparable with those in Poland. Furthermore, the concentration of As in these spices were lower than the maximum permissible limit.

  2. Application of the neutron activation analysis technique in trace elements analysis

    Khamis, I.; Sarheel, A.; Al-Somel, N.

    2006-12-01

    The main objective in this study is the implementation k 0 -standardization method (single comparator method) using gold comparator as a routine method in neutron activation analysis laboratory in Engineering Nuclear Department. Cadmium ratio Rcd; Cd-ratio = [A s p/(A s p) C d] and the nuclear reactor constants (f=φ t h/φ e pi subcadimum thermal- to- epithermal neutron flux ratio and α with describing the φ e (E)∼ 1/E 1+α neutron flux distribution) were determined in the inner and outer irradiation sites at MNS Reactor. K 0 -IAEA software, which provided by the Agency, has been installed and applied in our laboratory. Trace elements in many kinds of samples (biological, environmental, alloy ...etc) were determined using K 0 -IAEA software. The results of standard reference materials (SRM's) obtained in this work show a good agreement with the certified values, and we got these results with a good accuracy closer to results which we got from relative NAA method. (author)

  3. Biotransformation of trace organic compounds by activated sludge from a biological nutrient removal treatment system.

    Inyang, Mandu; Flowers, Riley; McAvoy, Drew; Dickenson, Eric

    2016-09-01

    The removal of trace organic compounds (TOrCs) and their biotransformation rates, kb (LgSS(-)(1)h(-)(1)) was investigated across different redox zones in a biological nutrient removal (BNR) system using an OECD batch test. Biodegradation kinetics of fourteen TOrCs with initial concentration of 1-36μgL(-)(1) in activated sludge were monitored over the course of 24h. Degradation kinetic behavior for the TOrCs fell into four groupings: Group 1 (atenolol) was biotransformed (0.018-0.22LgSS(-)(1)h(-)(1)) under anaerobic, anoxic, and aerobic conditions. Group 2 (meprobamate and trimethoprim) biotransformed (0.01-0.21LgSS(-)(1)h(-)(1)) under anoxic and aerobic conditions, Group 3 (DEET, gemfibrozil and triclosan) only biotransformed (0.034-0.26LgSS(-)(1)h(-)(1)) under aerobic conditions, and Group 4 (carbamazepine, primidone, sucralose and TCEP) exhibited little to no biotransformation (<0.001LgSS(-)(1)h(-)(1)) under any redox conditions. BNR treatment did not provide a barrier against Group 4 compounds. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Determination of arsenic and other trace elements in cosmetics by instrumental neutron activation analysis

    Gonzalez Cepeda, A.M.; Cienfuegos Silva, E.E.

    1978-01-01

    A general survey of trace-elements in different types of cosmetics, in particular arsenic, was carried out in order to detect elements that might be detrimental to human health. The samples were analyzed by instrumental neutron activation analysis and high-resolution gamma-ray spectrometry with Ge(Li) detectors. Different amounts of Br and Sb, detected in almost all the samples, produced interferencies in the determination of As when the 559 KeV photopeak was used. Since the triplet formed could not be resolved by the Ge(Li) detector, a mathematical procedure was developed using the 776 KeV gamma-ray emission of 82-Br and various factors found experimentally. This procedure was checked using laboratory-made samples of known concentrations and the results obtained had good precision and accuracy. In addition to arsenic the elements Co, Cr, Br, Sc, Fe and Zn were also quantitatively determined. Those cosmetics made from inorganic raw materials have an As concentration higher than those elaborated from organic materials. (EC)

  5. Major and trace elements assessment in sediment from Ituparanga reservoir, by activation analysis and ICP OES

    Silva, Sharlleny A.; Bevilacqua, Jose Eduardo; Favaro, Deborah I.T.

    2011-01-01

    The Ituparanga reservoir was built to generate electric power by the LIGHT Company and started its operation in 1912. It is fed by the Una, Sorocamirim and Sorocabucu rivers. This reservoir supplies water to a population of 600.000. This water system is affected by irregular soil occupation and urban development which has caught CETESB's (Environmental Company of Sao Paulo State) attention. In this study four geo-referenced sampling points were used and bottom sediment samples were collected. The sediment samples were dried at 400 deg C, ground in an agate mortar, sieved (200 mesh) and again homogenized. The instrumental neutron activation analysis was applied to the sediment samples in order to determine some major elements (Fe, K and Na), trace (As, Ba, Br, Co, Cr, Cs, Hf, Rb, Sb, Sc, Ta, Tb, Th, U and Zn) and rare earth (Ce, Eu, La, Lu, Nd, Sm, Tb and Yb) elements. By using ICP OES metals determination for Cd, Cr, Cu, Pb and Ni was undertaken after digestion procedure according to the 3051 method from US EPA. The methodology validation for precision and accuracy was carried out by reference material analyses. For metals Cd, Cr, Cu, Pb and Ni the concentration values were compared to the oriented values from Environmental Canada (TEL and PEL). The Enrichment Factor (EF) was calculated for sediment contamination assessment. (author)

  6. Studies of trace element determinations in nails by neutron activation analysis method

    Aguiar, Amilton Reinaldo; Saiki, Mitiko

    1996-01-01

    The purpose of this work was to develop the neutron activation analysis for trace element determinations in nails in order to apply this method to the study of the cystic fibrosis disease. It was verified that the elements Al, As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Se and Zn can be determined by using short and long irradiations with thermal neutron flux from 10 11 to 10 13 n.cm -2 . -1 at the IEA-R1 nuclear research reactor. The washing solutions of triton-X100, NH 4 OH and acetone were tested in order to eliminate external contaminants from the nail samples. The nail analyses of the individual fingers from both of hands showed that the samples must be collected from all the fingers from both of hands to have a representative sample. The precision and the accuracy of the results were also examined by analyzing NIES 10C Rice Flour, IUPAC Bowen's Kale and NIST 1572 Citrus Leaves reference materials. (author)

  7. Determination of trace elements in drinking water by neutron activation analysis

    Munita, C.S.; Abe, R.M.; Andrade e Silva, L.G. de.

    1988-10-01

    The concentracao of Hg, Cr, Zn, Fe and Co has been determined in fresh drinking water by a combination of preconcentration and neutron activation analysis. In order to preconcentrate the trace metals, a Chelex-100 resin in the NH + - form has been employed and it was not necessary to use special NH 4 + - form has been employed and it was not necessary to use special agents for the adsorption of the elements which are practically quantitatively retained by the resin. The retention of each element during the preconcentration was investigated using radioactive tracers. Selenium is known as a strongly interferent element for the analysis since the (n,Π) produced 75 Se has a Π-line at 0.279 MeV which coincides with the only Π-line of 203 Hg. The separation was made by a selective retention of mercury. After the sample had passed through the resin, the column was transfered to a polythylene envelope and irradiated at a neutron flux of about 5.10 12 ncm -2 s -1 for 8 h. For Hg the resin was irradiated in quartz ampoules. The samples were counted 15 days after the irradiation. The present method is superior to most other Chelex-100 separation procesures where elements of interest are eluted from the resin prior determinations thereby introducing the possibility of additional reagent blanks and incomplete as well as non-reproducible recoveries. (author) [pt

  8. European activities in space radiation biology and exobiology

    Horneck, G.

    1996-01-01

    In view of the space station era, the European Space Agency has initiated a review and planning document for space life sciences. Radiation biology includes dosimetry of the radiation field and its modification by mass shielding, studies on the biological responses to radiation in space, on the potential impact of space flight environment on radiation effects, and assessing the radiation risks and establishing radiation protection guidelines. To reach a better understanding of the processes leading to the origin, evolution and distribution of life, exobiological activities include the exploration of the solar system, the collection and analysis of extraterrestrial samples and the utilization of space as a tool for testing the impact of space environment on organics and resistant life forms. (author)

  9. REP activities of the conference of radiation control program directors

    Bevill, B.

    1995-01-01

    This talk provides an overview of the activities within the Conference of Radiation Control Program Directors associated with Radiological Emergency Preparedness. Included are summaries of interactions with FEMA, with US DOE, with US FDA, and with US DOT

  10. Collection/concentration of trace uranium for spectrophotometric detection using activated carbon and first-derivative spectrophotometry

    El-Sayed, A.A.; Hamed, M.M.; El-Reefy, S.; Hmmad, H.A.

    2007-01-01

    The need exists for preconcentration of trace and ultratrace amounts of uranium from environmental, geological and biological samples. The adsorption of uranium on various solids is important from the purification, environmental, and radioactivity waste disposal points of view. A method is described for the determination of traces of uranium using first-derivative spectrophotometry after adsorptive preconcentration of uranium on activated carbon. Various parameters that influence the adsorptive preconcentration of uranium on activated carbon, viz., pH, amounts of activated carbon and time of stirring and interference of metals have been studied. First-derivative spectrophotometry in conjunction with adsorptive preconcentration of uranium on activated carbon is used for determining uranium at concentration levels down to 20 ppb (w/v). (orig.)

  11. Trace elements in some new Romanian phytotherapeutic drugs determined by neutron activation analysis

    Preoteasa, E.A.; Salagean, M.; Pantelica, A.; Ionescu-Tirgoviste, C.

    1997-01-01

    Instrumental neutron activation analysis (INAA) has been performed on four new Romanian phytotherapeutic drugs registered us Fitolip, Fitodiab, Retinomion and Neuromion. The drugs were very well tolerated in clinical trials and are used in diabetes and other chronic diseases. They were prepared in the form of tablets made from dried powders of fruits, flowers, leaves and shells of plants used in non-conventional medicine. All four products are reach in various bioactive substances such as flavones, flavonoids, anthocyans, terpenes, rutosides, vitamins and essential fatty acids. Samples and multielemental reference materials were irradiated in a thermal neutron flux of 1.1 x 10 11 n.cm -2 .s -1 and measured with a high resolution Ge(Li) detector. 28 mineral elements were found, including Mg, K, Ca, Na and Fe at percent and sub-percent levels; Cl, Al and Mn between tens and thousands of ppm; Zn, Br, Rb and Ba up to tens of ppm; Cr, Cu, Co and V in the ppm range; and Sc, As, Sb, Cs, Lu, La, Ce, Sm, Hf, Au, Hg and Th up to hundreds of ppb. The intake of mineral elements provided by a cure of 3 pills/day shows the following: 1. None of the toxic elements As and Hg in the four drugs exceeds a noxious level; 2. Mg is the most abundant macro-element and a cure covers 15 - 60 % of the daily requirements; 3. Among essential microelements, Co may provide even more than 100% of the daily requirements; other elements may give small but significant fractions of the necessary daily amounts, e.g. 3-30% for Cr, 5-20% for Mn, and 2-10% for Fe; 4. The supply of Al, the most abundant unessential metal represents 6 - 40 % of the known daily intake. Thus a 3 pills/day cure could contribute positively to the therapy of various diseases by providing Mg, Mn, Cr (a trace element deficient in diabetes), Fe and Co, but higher daily doses could result in a Co oversupply. Further in INAA studies on biological examples from patients taking these new medicines are needed to understand the

  12. Radiation traces in exportation food samples of Parana State, Brazil; Tracos radioativos em amostras alimentares de exportacao do Parana

    Scheibel, Viviane

    2002-02-01

    This work deals with radioactive traces measurements in foodstuffs produced at the State of Parana, with large export rate and also of nutritious products of some regional trading companies. The measured foods were: sulfite treated sugar, tea, mint candy, soy in grain, soy crumb, gross soy oil, gum free oil and commercial refined soy oil. Six samples of each lot of the analyzed material were prepared, which represent a sampling with 90% of confidence. The samples were sealed in Marinelli beaker of 2.1 L completely filled and kept during 40 days until secular equilibrium was achieved. The counting time for each measure was of 48 hours. Measurements were carried out by gamma-ray spectrometry employing a HPGe detector with 10% of relative efficiency, coupled to standard nuclear electronics and a 8 l multichannel card. The acquisition of the data was accomplished with the software Maestro{sup TM}, version 3.2. The energy resolution of the {sup 137} Cs 661.62 keV gamma line was 1.75 keV. The larger intensity gamma lines observed in the spectra were from the following radionuclides: {sup 228} Ac, {sup 208} Tl, {sup 212} Pb of the {sup 232} Th series, {sup 214} Bi and {sup 214} Pb from the {sup 238} U series, {sup 227} Ac from the {sup 235} U series and {sup 40} K. Activities and lower level of detection limits were calculated according to the International Agency of Atomic Energy norms.The detector efficiency was measured using a {sup 152} Eu certified source and IAEA-375 and IAEA-326 certified reference materials. For most of the radionuclides it was possible only the measurement of the minimum activity detectable in the foodstuffs. Self-attenuation corrections were accomplished with support literature results. The most important activity observed was that of {sup 40} K, whose value measured for soy in natura was 745.0 {sup +}-{sup 9}.1 Bq/kg and for the crumb soy 1473 {+-} 15 Bq/kg.. he measured activities of the several analyzed foods were compatible with the values

  13. Current radiation protection activities of the International Atomic Energy Agency

    Webb, G.A.M.

    1996-01-01

    The International Atomic Energy Agency (IAEA) program of the Radiation Safety Section is described in this paper. The Section has two main components: (1) the development of consensus safety documentation and (2) the use of that documentation as the basis for assisting countries to deal safely with their applications of radiation and radioactivity. Main activities of the section are listed for each of these components. Activities include documentation, coordinated research programs, and assistance to developing countries. 14 tabs

  14. Radiation dosimetry activities in the Netherlands

    Broerse, J.J.; Mijnheer, B.J.

    1986-07-01

    The Netherlands Commission for Radiation Dosimetry (NCS) was officially established on 3 September 1982 with the aim of promoting the appropriate use of dosimetry of ionizing radiation both for scientific research and practical applications. The present report provides a compilation of the dosimetry acitivities and expertise available in the Netherlands, based on the replies to a questionnaire mailed under the auspices of the NCS and might suffer from some incompleteness in specific details. The addresses of the Dutch groups with the names of the scientists are given. Individual scientists, not connected with a scientific group, hospital or organization have not been included in this list. Also the names of commercial firms producing dosimetric systems have been omitted. (Auth.)

  15. Factors affecting neutron measurements and calculations. Part C. Trace element concentrations in granite and their impact on thermal neutron activation

    Ruehm, Werner; Huber, Thomas; Nolte, Eckehart; Kato, Kazuo; Imanaka, Tetsuji; Egbert, Stephen D.

    2005-01-01

    Trace elements such as Li, B, Sm, and Gd can, despite their low elemental concentration in mineral materials, influence thermal neutron activation in Hiroshima and Nagasaki samples, due to their high thermal neutron absorption cross sections. This was demonstrated for a granite core, where the addition of those trace elements to the elemental composition of granite reduces the production of 152 Eu by some 25% at a depth of 25 cm from the surface. If typical concentrations of those trace elements are added to DS02 reference soil, however, the production of 152 Eu one meter above ground is not changed significantly, because of the high water content of the soil. This indicates that DS02 soil represents a reasonable reference material for the air-over-ground transport calculations. It must be kept in mind, however, that the local environment of any sample investigated for thermal neutron activation might be characterized by other elemental compositions. In particular, trace element and hydrogen concentrations could be considerably different from those used for DS02 reference soil. As an example it was demonstrated that in a granite gravestone thermal neutron activation of 36 Cl close to the surface might be, in the worst case, reduced by some 30%, due to increased local granite concentration in this type of environment. Beside other parameters such as, for example, individual sample geometry, the variability of trace elements in soil might be one reason for the variability that is observed in the individual thermal neutron activation measurements (Gold 1995). It is necessary, therefore, to carefully model the exposure geometry of the exposed material, its chemical composition, and the surrounding interface materials in order to obtain the best possible agreement in comparisons between calculated and measured data for thermal neutrons. (author)

  16. Charged particles radiation measurements with Liulin-MO dosimeter of FREND instrument aboard ExoMars Trace Gas Orbiter during the transit and in high elliptic Mars orbit

    Semkova, Jordanka; Koleva, Rositza; Benghin, Victor; Dachev, Tsvetan; Matviichuk, Yuri; Tomov, Borislav; Krastev, Krasimir; Maltchev, Stephan; Dimitrov, Plamen; Mitrofanov, Igor; Malahov, Alexey; Golovin, Dmitry; Mokrousov, Maxim; Sanin, Anton; Litvak, Maxim; Kozyrev, Andrey; Tretyakov, Vladislav; Nikiforov, Sergey; Vostrukhin, Andrey; Fedosov, Fedor; Grebennikova, Natalia; Zelenyi, Lev; Shurshakov, Vyacheslav; Drobishev, Sergey

    2018-03-01

    ExoMars is a joint ESA-Rosscosmos program for investigating Mars. Two missions are foreseen within this program: one consisting of the Trace Gas Orbiter (TGO), that carries scientific instruments for the detection of trace gases in the Martian atmosphere and for the location of their source regions, plus an Entry, Descent and landing demonstrator Module (EDM), launched on March 14, 2016; and the other, featuring a rover and a surface platform, with a launch date of 2020. On October 19, 2016 TGO was inserted into high elliptic Mars' orbit. The dosimetric telescope Liulin-MO for measuring the radiation environment onboard the ExoMars 2016 TGO is a module of the Fine Resolution Epithermal Neutron Detector (FREND). Here we present first results from measurements of the charged particle fluxes, dose rates, Linear Energy Transfer (LET) spectra and estimation of dose equivalent rates in the interplanetary space during the cruise of TGO to Mars and first results from dosimetric measurements in high elliptic Mars' orbit. A comparison is made with the dose rates obtained by RAD instrument onboard Mars Science Laboratory during the cruise to Mars in 2011-2012 and with the Galactic Cosmic Rays (GCR) count rates provided by other particle detectors currently in space. The average measured dose rate in Si from GCR during the transit to Mars for the period April 22-September 15, 2016 is 372 ± 37 μGy d-1 and 390 ± 39 μGy d-1 in two perpendicular directions. The dose equivalent rate from GCR for the same time period is about 2 ± 0.3 mSv d-1. This is in good agreement with RAD results for radiation dose rate in Si from GCR in the interplanetary space, taking into account the different solar activity during the measurements of both instruments. About 10% increase of the dose rate, and 15% increase of the dose equivalent rate for 10.5 months flight is observed. It is due to the increase of Liulin-MO particle fluxes for that period and corresponds to the overall GCR intensity

  17. Activities of RADA in promotion of radiation applications

    Tanase, M.; Funayama, Y.; Tanaka, O.

    2007-01-01

    Radiation Application Development Association (RADA) was established to promote the applications of radiation in 1968. Among the activities of RADA, we have five works directly to promote the application of radiation to the public. One of them is to publish a quarterly journal 'Radiation and Industries' which carries comprehensive articles on timely topics of radiation-based applications, patent information etc. And also RADA organizes the Radiation Process Symposium, which has been held every other year strictly, for exchange of information on radiation applications. The symposium started in 1985, where researchers and engineers in various and wide fields have been discussed on the radiation applications to industries. As the third, RADA distributes beautiful ornaments, which were produced by gamma-ray irradiation of crystals, glass and pearls, to promote better understanding of radiation. We also have taken charge of two businesses contracted with the Ministry of Education, Culture, Sports, Science and Technology (MEXT). One is to hold seminars on radiation and nuclear energy for teachers of primary, junior high and senior high schools to enhance their understanding about radiation and nuclear energy, and to facilitate the use in their classrooms of such knowledge concerning energy, environment and their effects on our lives. The other is to facilitate the transfer of technologies of radiation application in the realms of industry, agriculture, medical treatment, etc. through dispatching of experts, releasing data on radiation applications, and organizing technical seminars. Recently, we arranged an opportunity to use neutrons from research reactors through trial experiments for transferring the technology to industries. (author)

  18. Multiple Seismic Array Observations for Tracing Deep Tremor Activity in Western Shikoku, Japan

    Takeda, T.; Matsuzawa, T.; Shiomi, K.; Obara, K.

    2011-12-01

    Deep non-volcanic tremors become very active during episodic slow-slip events in western Japan and Cascadia. The episodic tremor and slow-slip events in western Shikoku, Japan, occur at a typical interval of 6 months. Recently, it has been reported that tremor migration activity is complex and shows different migrating directions depending on time scales (Ghosh et al., 2010). Such characteristics of tremor are important to understand the mechanism of tremor and the relationship between tremor and SSEs. However it is difficult to determine the location of tremors with high accuracy because tremors show faint signals and make the identification of P/S-wave arrivals difficult. Seismic array analysis is useful to evaluate tremor activity, especially to estimate the arrival direction of seismic energy (e.g. Ueno et al., 2010, Ghosh et al., 2010), as it can distinguish multiple tremor sources occurring simultaneously. Here, we have conducted seismic array observation and analyzed seismic data during tremor activity by applying the MUSIC method to trace tremor location and its migration in western Shikoku. We have installed five seismic arrays in western Shikoku since January 2011. One of the arrays contains 30 stations with 3-component seismometers with a natural frequency of 2 Hz (Type-L array). The array aperture size is 2 km and the mean interval between stations is approximately 200 m. Each of the other arrays (Type-S array) contains 9 seismic stations with the same type of seismometers of the Type-L array, and is deployed surrounding the Type-L array. The small array aperture size is 800 m and its mean station interval is approximately 150 m. All array stations have recorded continuous waveform data at a sampling of 200Hz. In May 2011, an episodic tremor and a short-term slip event occurred for the first time during the observation period. We could retrieve the array seismic data during the whole tremor episode. The analysis of data from the type-L array confirms

  19. Uranium trace and alpha activity characterization of coal and fly ash using particle track etch technique

    Chakravarti, S.K.

    1991-01-01

    Uranium is extensively found in carbonaceous components of sedimentary rocks and is considered to be accumulated in coals during the coalification process through the geological times. Burning of coal is mainly responsible for a manifold increase in the concentration of radioactive nuclides in atmosphere precipitates. Fly ash being an incombustible residue and formed from 90% of the inorganic material in coal, escapes into the atmosphere and constitutes a potential hazard. Also its use as one of the pozzolanic materials in the products of concrete, bricks etc and filling of ground cavities is even more hazardous because of the wall radioactivity, besides emission and diffusion of radon. This paper reports a simple method called Particle Track Etch (PTE) technique, for trace determination of uranium content in coal and fly ash samples by making use of low cost and versatile plastic detectors known as Solid State Nuclear Track Detectors (SSNTDs). Total alpha activity has also been estimated using these SSNTDs. The values of uranium concentration in coal samples are found to range from 1.1 to 3.6 ppm (uniform component) and 33 to 46 ppm (non-uniform part) whereas in fly ash, it varies from 8 to 11 ppm (uniform) and 55 to 71 ppm in non-uniform range. It is also observed that the alpha activity is a function of uranium concentration for most of the natural samples of coal studied except for mixtures of fly ash samples where relationship is found to be on higher side. (author). 13 refs., 2 tabs., 1 fig

  20. Radiation shielding activities at the OECD/Nuclear Energy Agency

    Sartori, Enrico; Vaz, Pedro

    2000-01-01

    The OECD Nuclear Energy Agency (NEA) has devoted considerable effort over the years to radiation shielding issues. The issues are addressed through international working groups. These activities are carried out in close co-ordination and co-operation with the Radiation Safety Information Computational Center (RSICC). The areas of work include: basic nuclear data activities in support of radiation shielding, computer codes, shipping cask shielding applications, reactor pressure vessel dosimetry, shielding experiments database. The method of work includes organising international code comparison exercises and benchmark studies. Training courses on radiation shielding computer codes are organised regularly including hands-on experience in modelling skills. The scope of the activity covers mainly reactor shields and spent fuel transportation packages, but also fusion neutronics and in particular shielding of accelerators and irradiation facilities. (author)

  1. Effect of radiation on activity of sulphate reducing bacteria

    Agaev, N.M.; Smorodin, A.E.; Gusejnov, M.M.

    1985-01-01

    The effect of γ-radiation on activity of sulphate reducing bacteria has been studied. Concentration of biogenic hydrogen, generated in the medium, is the main criterion, characterizing corrosion activity of the bacteria studied. The developed method of suppression of active development of sulfate reducing bacteria considerably reduces, and at lethal doses of γ-radiation eliminates altogether the bacteria activity and formation of the main corrosion agent-hydrogen sulphide-in the medium and that, in its turn, liquidates hydrogen sulphide corrosion

  2. Automatic fault tracing of active faults in the Sutlej valley (NW-Himalayas, India)

    Janda, C.; Faber, R.; Hager, C.; Grasemann, B.

    2003-04-01

    In the Sutlej Valley the Lesser Himalayan Crystalline Sequence (LHCS) is actively extruding between the Munsiari Thrust (MT) at the base, and the Karcham Normal Fault (KNF) at the top. The clear evidences for ongoing deformation are brittle faults in Holocene lake deposits, hot springs activity near the faults and dramatically younger cooling ages within the LHCS (Vannay and Grasemann, 2001). Because these brittle fault zones obviously influence the morphology in the field we developed a new method for automatically tracing the intersections of planar fault geometries with digital elevation models (Faber, 2002). Traditional mapping techniques use structure contours (i.e. lines or curves connecting points of equal elevation on a geological structure) in order to construct intersections of geological structures with topographic maps. However, even if the geological structure is approximated by a plane and therefore structure contours are equally spaced lines, this technique is rather time consuming and inaccurate, because errors are cumulative. Drawing structure contours by hand makes it also impossible to slightly change the azimuth and dip direction of the favoured plane without redrawing everything from the beginning on. However, small variations of the fault position which are easily possible by either inaccuracies of measurement in the field or small local variations in the trend and/or dip of the fault planes can have big effects on the intersection with topography. The developed method allows to interactively view intersections in a 2D and 3D mode. Unlimited numbers of planes can be moved separately in 3 dimensions (translation and rotation) and intersections with the topography probably following morphological features can be mapped. Besides the increase of efficiency this method underlines the shortcoming of classical lineament extraction ignoring the dip of planar structures. Using this method, areas of active faulting influencing the morphology, can be

  3. Application of neutron activation analysis to biological materials. Pt. 4. Approach to simultaneous determination of trace elements in human eye tissues with non-destructive neutron activation analysis

    Yamaguchi, T; Bando, M; Nakajima, A [Juntendo Univ., Tokyo (Japan). School of Medicine; Terai, M [Tokyo Metropolitan Univ. (Japan). Faculty of Science; Suzuki-Yasumoto, M [National Inst. of Radiological Sciences, Chiba (Japan)

    1980-01-01

    Fourteen trace elements (short-lived nuclides: Al, Br, Cu, Mn and V; long-lived nuclides: Ag, Au, Cd, Co, Cr, Fe, Sc, Se and Zn) in human eye tissues are determined simultaneously by non-destructive neutron activation analysis. The quantity of Al, Br, Fe, Se and Zn in the eye tissues (about 1 to more than 10 ..mu..g/g dry weight tissue) seems to be higher than that of other trace elements, although the content of each trace element in individual tissue is scattered in a wide range. Conjunctiva, iris (+ciliary body) and choroid (+pigment epithelium) seem to contain larger amount of various trace elements than other eye tissues. From correlation studies it is evident that the relative distribution of 14 trace elements in various eye tissues are similar, and furthermore the content of trace elements in the eye tissues may be correlated in each of the three groups (group A: Cd, Se and Zn; group B: Al, Cr, Fe, Se and V; group C: Al, Au, Fe and Se).

  4. Frequency-independent radiation modes of interior sound radiation: Experimental study and global active control

    Hesse, C.; Papantoni, V.; Algermissen, S.; Monner, H. P.

    2017-08-01

    Active control of structural sound radiation is a promising technique to overcome the poor passive acoustic isolation performance of lightweight structures in the low-frequency region. Active structural acoustic control commonly aims at the suppression of the far-field radiated sound power. This paper is concerned with the active control of sound radiation into acoustic enclosures. Experimental results of a coupled rectangular plate-fluid system under stochastic excitation are presented. The amplitudes of the frequency-independent interior radiation modes are determined in real-time using a set of structural vibration sensors, for the purpose of estimating their contribution to the acoustic potential energy in the enclosure. This approach is validated by acoustic measurements inside the cavity. Utilizing a feedback control approach, a broadband reduction of the global acoustic response inside the enclosure is achieved.

  5. Neutron activation analysis applied to the determination of trace elements in human nails

    Aguiar, Amilton Reinaldo

    2001-01-01

    There is a considerable interest in the determination of trace elements in human nails in order to use this tissue as a monitor of nutritional and healthy status of individuals, of occupational exposure diseases and of the environmental contamination. In this work, instrumental neutron activation analysis was applied to determine trace elements in finger nail clippings to make comparisons between the elemental concentrations obtained in nails from healthy individuals of a control group and those from cystic fibrosis (CF) patients. Firstly, a protocol for sample collection and preparation for analysis was established. Finger and toe nail samples from CF patients were collected at the Instituto da Crianca of Medicine School, University of Sao Paulo, SP. The nail samples from control group were collected from healthy adults and from children living in Sao Paulo city, SP. These samples were cleaned by stirring them witha a diluted Triton X100 solution and then by washing with distilled water and acetone. The analytical procedure consisted of irradiation nail samples and elemental standards in the IEA-R1m nuclear reactor under thermal neutro flux of about 10 12 n cm -2 s -1 , for short and long period irradiations. The activities of the radionuclides were measured using a gamma-ray spectrometer comprising an hyperpure Ge detector and associated electronic system. The biological reference materials Bovine Liver 1577b and Oyster Tissue 1566a, both from National Institute of Standards and Technology, USA were analysed in order to evaluate the accuracy and precision of the results. The analysis of variance (ANOVA) and F-test at the significance level of 5% were used to make a comparison between the sets of results obtained in this work. In the comparison of the results obtained for finger and toe nails from CF patients, the Br concentrations were higher in finger nails that those obtained for toe nails. For the control group of children, the finger nails presented different

  6. Minerals and trace elements determination in diets by neutron activation analysis

    Eiras, Maria Izabel O.; Favaro, Debora I.T.; Ribeiro, Marisilda; Cozzolino, Silvia M.F.

    2002-01-01

    In the present study 12 diets, each one consisting of a pool of seven day diets, composed by four meals: breakfast, lunch, dinner and snack, adequate in energy and macro nutrients according to the RDA (Recommended Daily Allowance) recommendations, were elaborated and offered to a group of 12 men (19-42 years). The diets were collected by duplicate portion technique and dried by two different processes: freeze drying and 60 deg C ventilated oven drying. In the total, 24 diets were analyzed. The content of some minerals and trace elements (Ca, Fe, Mg, Mn, Na, Se and Zn) were determined by Instrumental Neutron Activation Analysis. The validation of methodology was made by analysis of the reference materials Typical Diet (NIST SRM 1548 a ), Orchard Leaves (NIST SRM 1541) and Peach Leaves (NIST SRM 1547). The results observed by two different drying processes used were statistically compared by test T of Student. It was possible to conclude that the concentration means can be considered as statistically equal, within a significance level of 0.05. The daily intake values calculated from the concentration results were: 712 (± 59) mg Ca/day; 10.7 (± 0.8) mg Fe/ day; 3387 (± 16) mg K/ day; 275 (± 6) mg Mg/ day; 3.0 (± 0.5) mg Mn/ day; 3656 (± 699) mg Na/ day; 42 (± 6) μg Se/ day e 11.6 (± 2.4) mg Zn/ day. The calculated intake was compared to the new daily recommended values set by RDA (National Research Council-USA) for the range age of individuals studied. It was possible to conclude that the diets were adequate in Fe and Zn and inadequate for the other elements. Concerning the minerals Na and K we verified high daily intake levels and this was already observed in other Brazilian regional diets. (author)

  7. All-Optical Atom Trap Trace Analysis: Potential Use of 85Kr in Safeguards Activities

    Kohler, M.; Sahling, P.; Sieveke, C.; Kirchner, G.

    2015-01-01

    Sensitive measurement techniques for the detection of anthropogenic tracers demand measurement resolutions down to single atoms, as it has been demonstrated by the first atom trap trace analysis experiments. However, technical limitations had lowered the sample throughput to about 200 per year per machine. We have developed an all-optical apparatus which allows higher sample throughput and small sample sizes at the same time. Krypton-85 as anthropogenic isotope is an ideal tracer for nuclear activities since the only relevant source term is fission. An increased 85Kr concentration in an air sample indicates, that a plume was passing by during sampling. In practice, however, its applicability may be limited by the global and regional background concentrations caused by the emissions of nuclear fuel reprocessing plants. The potential of 85Kr monitoring for safeguards applications has been discussed extensively. Among these is the short range detection of elevated concentrations of 85Kr in the vicinity of reprocessing plants. Our ATTA technique needs sample sizes of about 1 l of air only and thus for the first time will allow simple environmental sampling of 85Kr with high spatial and temporal resolution. The design of such a study including local sampling and tracer transport modelling in proximity to a reprocessing plants is outlined. In addition, such a study could be used also for validating near-field atmospheric dispersion models if the 85Kr source term is known. The potential of environmental analyzes of 85Kr during an IAEA short-notice access is discussed. It is shown that it crucially depends on the emission dynamics after shut-down of fuel dissolution which needs further study. (author)

  8. Determination of essential trace elements in wine by neutron activation analysis

    Daniele, Anna Paula

    2016-01-01

    Several studies have been carried out for determining essential elements in foodstuffs, including wine, due to its important nutritional role in human body functions. It was shown that daily consumption of wine in moderation contributes significantly to the needs of essential elements in human body such as Ca, Co, Cr, Fe, K, Mg, Mn, Zn, V, among others, and has health benefits in the prevention of numerous diseases and longer life expectancy, related in particular to the intake of antioxidants such as polyphenolic compounds. Trace elements are good indicators of origin of wines and their concentrations can be used as criteria to ensure authenticity, quality and show that the tolerance limits established by law were respected throughout the production process. However, although Brazilian wine industry is among the 15 largest in the world, analytical studies for organic and inorganic compounds of wine content are still small when compared to other major producers. In this sense, this study aimed to evaluate some procedures of wine sample preparation to determine essential elements by Instrumental Neutron Activation Analysis (INAA) and compare the results with those determined by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP OES). Three sample preparation procedures were studied: freeze-drying, evaporation and dry ashing. The parameters studied were precision, accuracy and detection limit. ANOVA and Tukey-Kramer tests were applied to verify the statistical differences between the mean values obtained by the three wine preparation procedures for INAA with those means obtained by ICP OES. It was noticed that about 60% of results obtained by freeze-drying agreed with those obtained by ICP OES. (author)

  9. A research program on radiative, chemical, and dynamical feedback progresses influencing the carbon dioxide and trace gases climate effects

    1989-07-01

    This report summarizes the up-to-date progress. The program includes two tasks: atmospheric radiation and climatic effects and their objective is to link quantitatively the radiation forcing changes and the climate responses caused by increasing greenhouse gases. Here, the objective and approach are described. We investigate the combined atmospheric radiation characteristics of the greenhouse gases (H 2 O, CO 2 , CH 4 , N 2 O, CFCs, and O 3 ), aerosols and clouds. Since the climatic effect of increasing atmospheric greenhouse gases is initiated by perturabtion to the longwave thermal radiation, it is critical to understand better the radiation characteristics of the greenhouse gases and their relationship to radiatively-important aerosols and clouds; the latter reflect solar radiation (a cooling of the surface) and provide a greenhouse effect (a warming to the surface). Therefore, aerosol and cloud particles are an integral part of the radiation field in the atmosphere. 9 refs

  10. Trace metal depositional patterns from an open pit mining activity as revealed by archived avian gizzard contents.

    Bendell, L I

    2011-02-15

    Archived samples of blue grouse (Dendragapus obscurus) gizzard contents, inclusive of grit, collected yearly between 1959 and 1970 were analyzed for cadmium, lead, zinc, and copper content. Approximately halfway through the 12-year sampling period, an open-pit copper mine began activities, then ceased operations 2 years later. Thus the archived samples provided a unique opportunity to determine if avian gizzard contents, inclusive of grit, could reveal patterns in the anthropogenic deposition of trace metals associated with mining activities. Gizzard concentrations of cadmium and copper strongly coincided with the onset of opening and the closing of the pit mining activity. Gizzard zinc and lead demonstrated significant among year variation; however, maximum concentrations did not correlate to mining activity. The archived gizzard contents did provide a useful tool for documenting trends in metal depositional patterns related to an anthropogenic activity. Further, blue grouse ingesting grit particles during the time of active mining activity would have been exposed to toxicologically significant levels of cadmium. Gizzard lead concentrations were also of toxicological significance but not related to mining activity. This type of "pulse" toxic metal exposure as a consequence of open-pit mining activity would not necessarily have been revealed through a "snap-shot" of soil, plant or avian tissue trace metal analysis post-mining activity. Copyright © 2010 Elsevier B.V. All rights reserved.

  11. Trace metal depositional patterns from an open pit mining activity as revealed by archived avian gizzard contents

    Bendell, L.I., E-mail: bendell@sfu.ca

    2011-02-15

    Archived samples of blue grouse (Dendragapus obscurus) gizzard contents, inclusive of grit, collected yearly between 1959 and 1970 were analyzed for cadmium, lead, zinc, and copper content. Approximately halfway through the 12-year sampling period, an open-pit copper mine began activities, then ceased operations 2 years later. Thus the archived samples provided a unique opportunity to determine if avian gizzard contents, inclusive of grit, could reveal patterns in the anthropogenic deposition of trace metals associated with mining activities. Gizzard concentrations of cadmium and copper strongly coincided with the onset of opening and the closing of the pit mining activity. Gizzard zinc and lead demonstrated significant among year variation; however, maximum concentrations did not correlate to mining activity. The archived gizzard contents did provide a useful tool for documenting trends in metal depositional patterns related to an anthropogenic activity. Further, blue grouse ingesting grit particles during the time of active mining activity would have been exposed to toxicologically significant levels of cadmium. Gizzard lead concentrations were also of toxicological significance but not related to mining activity. This type of 'pulse' toxic metal exposure as a consequence of open-pit mining activity would not necessarily have been revealed through a 'snap-shot' of soil, plant or avian tissue trace metal analysis post-mining activity. - Research Highlights: {yields} Archived gizzard samples reveals mining history. {yields} Grit ingestion exposes grouse to cadmium and lead. {yields} Grit selection includes particles enriched in cadmium. {yields} Cadmium enriched particles are of toxicological significance.

  12. Identification case of evidence in timber tracing of Pinus radiate, using high-resolution melting (HRM) analysis.

    Solano, Jaime; Anabalón, Leonardo; Encina, Francisco

    2016-03-01

    Fast, accurate detection of plant species and their hybrids using molecular tools will facilitate assessment and monitoring of timber tracing evidence. In this study the origin of unknown pine samples is determined for a case of timber theft in the region of Araucania southern Chile. We evaluate the utility of the trnL marker region for species identification applied to pine wood based on High Resolution Melting. This efficient tracing methods can be incorporated into forestry applications such as certification of origin. The object of this work was genotype identification using high-resolution melting (HRM) and trnL approaches for Pinus radiata (Don) in timber tracing evidence. Our results indicate that trnL is a very sensitive marker for delimiting species and HRM analysis was used successfully for genotyping Pinus samples for timber tracing purposes. Genotyping samples by HRM analysis with the trnL1 approach allowed us to differentiate two wood samples from the Pinaceae family: Pinus radiata (Don) and Pseudotsuga menziesii (Mirb.) Franco. The same approach with Pinus trnL wood was not able to discriminate between samples of Pinus radiata, indicating that the samples were genetically indistinguishable, possibly because they have the same genotype at this locus. Timber tracing with HRM analysis is expected to contribute to future forest certification schemes, control of illegal trading, and molecular traceability of Pinus spp. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Low dose radiation enhances the Locomotor activity of D. melanogaster

    Seong, Ki Moon; Lee, Buyng Sub; Nam Seon Young; Kim, Ji Young; Yang, Kwang Hee; Choi, Tae In; Kim, Cha Soon [Radiation Effect Research Team, Radiation Health Research Institute, Korea Hydro and Nuclear Power Co., Ltd., Gyeongju (Korea, Republic of)

    2013-04-15

    Mild stresses at low level including radiation can induce the beneficial effects in many vertebrate and invertebrate species. However, a large amount of studies in radiation biology have focused on the detrimental effects of high dose radiation (HDR) such as the increased incidence of cancers and developmental diseases. Low dose radiation (LDR) induces biologically favorable effects in diverse fields, for example, cancer development, genomic instability, immune response, and longevity. Our previous data indicated that LDR promotes cells proliferation of which degree is not much but significant, and microarray data explained that LDR irradiated fruit flies showing the augmented immunity significantly changed the program for gene expression of many genes in Gene Ontology (GO) categories related to metabolic process. Metabolic process in development one of major contributors in organism growth, interbreeding, motility, and aging. Therefore, it is valuable to examine whether LDR change the physiological parameters related to metabolism, and how LDR regulates the metabolism in D. melanogaster. In this study, to investigate that LDR influences change of the metabolism, a representative parameter, locomotor activity. In addition, the activation of several cellular signal molecules was determined to investigate the specific molecular mechanism of LDR effects on the metabolism. We explored whether ionizing radiation affects the motility activity. We performed the RING assays to evaluate the locomotor activity, a representative parameter presenting motility of fruit flies. HDR dramatically decreased the motor activity of irradiated flies. Surprisingly, the irradiated flies at low dose radiation in both acute and chronic showed the significantly increased locomotor activity, compared to non-irradiated flies. Irradiation would induce change of the several signal pathways for flies to respond to it. The activation of some proteins involved in the cells proliferation and stress

  14. 1994 activity report: Stanford Synchrotron Radiation Laboratory

    Cantwell, K.; Dunn, L.

    1994-01-01

    The SSRL facility delivered 89% of the scheduled user beam to 25 experimental stations during 6.5 months of user running. Users from private industry were involved in 31% of these experiments. The SPEAR accelerator ran very well with no major component failures and an unscheduled down time of only 2.9%. In addition to this increased reliability, there was a significant improvement in the stability of the beam. The enhancements to the SPEAR orbit as part of a concerted three-year program were particularly noticeable to users. The standard deviation of beam movement (both planes) in the last part of the run was 80 microns, major progress toward the ultimate goal of 50-micron stability. This was a significant improvement from the previous year when the movement was 400 microns in the horizontal and 200 microns in the vertical. A new accelerator Personal Protection System (PPS), built with full redundancy and providing protection from both radiation exposure and electrical hazards, was installed in 1994. It is not possible to describe in this summary all of the scientific experimentation which was performed during the run. However, the flavor of current research projects and the many significant accomplishments can be realized by the following highlights: A multinational collaboration performed several experiments involving x-ray scattering from nuclear resonances; Studies related to nuclear waste remediation by groups from Los Alamos National Laboratory and Pacific Northwest Laboratories continued in 1994; Diffraction data sets for a number of important protein crystals were obtained; During the past two years a collaboration consisting of groups from Hewlett Packard, Intel, Fisons Instruments and SSRL has been exploring the utility of synchrotron radiation for total reflection x-ray fluorescence (TRXRF); and High-resolution angle-resolved photoemission experiments have continued to generate exciting new results from highly correlated and magnetic materials

  15. Radiation protection activities around the CERN accelerators

    Silari, M.

    1997-01-01

    The staff of the Survey Section of Radiation Protection (RP) working around the CERN accelerators were as usual very busy. The LEP2 programme is now fully on its way, with the installation of additional superconducting RF cavities carried out during both the winter and summer shutdowns. The LEP energy per beam was thus increased to 80.5 GeV in summer and to 86 GeV in autumn. ACOL and LEAR ended their operational life on 19 December producing, for the last time, antiprotons for the experiments in the South Hall; all experiments will be dismantled in 1997. This programme will be partly replaced by the future Antiproton Decelerator, which was approved by the Research Board in November. Several experiments also came to their end in the North and West Experimental Areas of the SPS. NA44 (in EHN1) and NA47 (in EHN2) ended this year. All experiments installed in beam lines HI, H3, XI and X3 in the West Area also terminated, as these beam lines will be dismantled in the course of 1997 to make room for test facilities for the LHC. Several modifications in the West and North Experimental Areas have already been undertaken at the end of the year and will be continued in 1997. Some equipment installed in the West Area will be moved to the North Area. In addition to routine work, several measurements of synchrotron radiation were made in LEP for the two new energy levels reached in 1996. A number of dedicated measurements were also undertaken in EHN1 (North Area) at the end of the year, during the lead-ion run which closed the physics period. A detailed assessment of releases of radioactivity from the ISOLDE facility was also made

  16. 1994 activity report: Stanford Synchrotron Radiation Laboratory

    Cantwell, K.; Dunn, L. [eds.

    1994-01-01

    The SSRL facility delivered 89% of the scheduled user beam to 25 experimental stations during 6.5 months of user running. Users from private industry were involved in 31% of these experiments. The SPEAR accelerator ran very well with no major component failures and an unscheduled down time of only 2.9%. In addition to this increased reliability, there was a significant improvement in the stability of the beam. The enhancements to the SPEAR orbit as part of a concerted three-year program were particularly noticeable to users. The standard deviation of beam movement (both planes) in the last part of the run was 80 microns, major progress toward the ultimate goal of 50-micron stability. This was a significant improvement from the previous year when the movement was 400 microns in the horizontal and 200 microns in the vertical. A new accelerator Personal Protection System (PPS), built with full redundancy and providing protection from both radiation exposure and electrical hazards, was installed in 1994. It is not possible to describe in this summary all of the scientific experimentation which was performed during the run. However, the flavor of current research projects and the many significant accomplishments can be realized by the following highlights: A multinational collaboration performed several experiments involving x-ray scattering from nuclear resonances; Studies related to nuclear waste remediation by groups from Los Alamos National Laboratory and Pacific Northwest Laboratories continued in 1994; Diffraction data sets for a number of important protein crystals were obtained; During the past two years a collaboration consisting of groups from Hewlett Packard, Intel, Fisons Instruments and SSRL has been exploring the utility of synchrotron radiation for total reflection x-ray fluorescence (TRXRF); and High-resolution angle-resolved photoemission experiments have continued to generate exciting new results from highly correlated and magnetic materials.

  17. Quantification of trace elements in protein bands by synchrotron radiation x-ray fluorescence after isoelectric focusing separation of human hemoglobin

    Gao Yuxi; Chen Chunying; Li Bai; He Wei; Huang Yuying; Chai Zhifang

    2005-01-01

    The role and effects of a trace element in a particular organism strongly depend on its particular chemical forms in which the element is present. Therefore, the bulk content or concentration of an element in the organism of interest is often meaningless in judging its biological significance. To understand bioavailability, transportation, cell uptake, metabolism, toxicity, and other biological behaviors of trace elements in the body, information is needed about speciation of trace element, especially about distribution of metal-containing proteins. Development of appropriate methods for speciation analysis is therefore required. Synchrotron radiation x-ray fluorescence (SRXRF) is a sensitive method for multielemental analysis with detection limit of 10 ng/g. It has been successfully used for imaging and quantifying trace elements in various pathological and healthy tissues, even in a single cell, to help understand the mechanism of diseases and the biochemistry of elements. In our previous work, the technique was combined with electrophoresis to study distribution of metalloproteins in biological samples, but the quantitative analysis of trace elements in protein bands after electrophoresis was still unrealized. In this study, a procedure has been proposed for quantification of Fe, Cu, and Zn in protein bands with SRXRF analysis after isoelectric focusing (IEF) separation. Calibration standards were prepared by adding certain amounts of metal ions and free-metal proteins to electrophoresis gel. Human hemoglobin was separated with IEF, and Fe, Cu, and Zn in protein bands were analyzed by SRXRF. The calibration curves can be obtained in a range of 0-8 mg/kg metals and a linear relationship between dosage of metals and fluorescent intensity can be observed (r 2 > 0.99). The method provides the detection limits of 2.43, 1.12, and 0.96 mg/kg for Fe, Cu and Zn, and the recoveries of 90.4 and 115.7 % for Fe and Zn, respectively. The hyphenated technique of SRXRF and IEF

  18. Activation and radiation damage in the environment of hadron accelerators

    Kiselev, Daniela

    2013-01-01

    A component which suffers radiation damage usually also becomes radioactive, since the source of activation and radiation damage is the interaction of the material with particles from an accelerator or with reaction products. However, the underlying mechanisms of the two phenomena are different. These mechanisms are described here. Activation and radiation damage can have far-reaching consequences. Components such as targets, collimators, and beam dumps are the first candidates for failure as a result of radiation damage. This means that they have to be replaced or repaired. This takes time, during which personnel accumulate dose. If the dose to personnel at work would exceed permitted limits, remote handling becomes necessary. The remaining material has to be disposed of as radioactive waste, for which an elaborate procedure acceptable to the authorities is required. One of the requirements of the authorities is a complete nuclide inventory. The methods used for calculation of such inventories are presented,...

  19. Conversion Efficiency of Photosynthetically Active Radiation Into Acacia mearnsii Biomass

    Elder Eloy

    2018-02-01

    Full Text Available ABSTRACT The objective of this experiment was to determine the conversion efficiency of intercepted photosynthetically active radiation into biomass of Acacia mearnsii De Wild. seedlings. A forest species, plastic tubes (90 cm3, and 11 evaluation periods (up to 180 days after emergence were used in this study. The leaf area index (LAI, total dry biomass (BIO, global solar radiation (GSR, cumulative intercepted photosynthetically active radiation (PARic, and conversion efficiency of radiation (εb were determined using a pyranometer (LI200X, LICOR. The value of εb in BIO seedlings of Acacia mearnsii was 7.76 g MJ-1. LAI was directly related to the efficiency of PARic, and this influenced the development, production potential and accumulation of BIO. The value of GSR flow was 11.81 MJ m-2 day-1, while the value inside the greenhouse was 6.26 MJ m-2 day-1.

  20. The influence of physical activity on hair toxic and essential trace element content in male and female students.

    Zaitseva, Irina P; Skalny, Andrey A; Tinkov, Alexey A; Berezkina, Elena S; Grabeklis, Andrei R; Skalny, Anatoly V

    2015-02-01

    The primary aim of the current study is to estimate the effect of different physical activity levels on hair trace element content in male and female students. A total of 113 students (59 women and 54 men) of P. G. Demidov Yaroslavl State University (Yaroslavl, Russia) took part in the current investigation. According to the level of the physical activity, all students were divided into three groups: high, medium, and low physical activity. Essential and toxic metal content (μg/g) in hair samples was assessed by inductively coupled plasma mass spectrometry using NexION 300D + NWR213 (Perkin-Elmer, USA). The obtained data show that hair iodine, zinc, arsenic, nickel, and tin levels are not related to physical activity in male and female students. At the same time, increased physical activity is associated with decreased hair copper, vanadium, bismuth, and mercury content in comparison to the low physical activity groups. Students with higher physical activity are also characterized by significantly higher hair cobalt, iron, manganese, selenium, cadmium, lithium, and lead concentrations. Finally, statistical analysis has revealed maximal gender differences in hair trace element content in the high physical activity groups, whereas in the low activity groups, the hair metal concentrations were nearly similar in females and males.

  1. Active moss biomonitoring of trace elements with Sphagnum girgensohnii moss bags in relation to atmospheric bulk deposition in Belgrade, Serbia

    Anicic, M.; Tasic, M.; Frontasyeva, M.V.; Tomasevic, M.; Rajsic, S.; Mijic, Z.; Popovic, A.

    2009-01-01

    Active biomonitoring with wet and dry moss bags was used to examine trace element atmospheric deposition in the urban area of Belgrade. The element accumulation capability of Sphagnum girgensohnii Russow was tested in relation to atmospheric bulk deposition. Moss bags were mounted for five 3-month periods (July 2005-October 2006) at three representative urban sites. For the same period monthly bulk atmospheric deposition samples were collected. The concentrations of Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, and Pb were determined by instrumental neutron activation analyses and atomic absorption spectrometry. Significant accumulation of most elements occurred in the exposed moss bags compared with the initial moss content. High correlations between the elements in moss and bulk deposits were found for V, Cu, As, and Ni. The enrichment factors of the elements for both types of monitor followed the same pattern at the corresponding sites. - Accumulated trace elements in the moss Sphagnum girgensohnii reflect atmospheric deposition

  2. Legal and technical analysis of the activities involving radiation applications

    Borges, J.C.

    1991-01-01

    Activities related to radiation applications have been worldwide target of studies concerning biology, medicine, sociology, psychology and law, since prediction of the possible risks and harms associated with the use of radiation, depends on probabilities not easy to quantify, mainly in the most common low-dose situations. In Brazil, legislation generated in the last forty years did not match evolution of the scientific domains related above. This way, more recent rules not rarely conflict with older regulations, without revoking them. (author)

  3. Determination of trace elements in Katana (Japanese sword) by neutron activation analysis with multidimensional γ-ray spectrometry

    Okada, Y.; Hirai, S.; Ohya, S.; Kimura, Atsushi; Hatsukawa, Yuichi; Toh, Yosuke; Koizumi, Mitsuo; Oshima, Masumi

    2006-01-01

    In this study, we tried to measure trace elements (As and Sb) in Katana (Japanese swords) by multidimensional γ-ray spectrometry method (GEMINI-II) and conventional counting method for neutron activation analysis (NAA). The determined values by GEMINI-II and conventional counting were in good agreement with. Using the multidimensional γ-ray spectrometry (GEMINI-II) to determine As and Sb was improved by 7 times and 10 times compared with the conventional counting method. (author)

  4. Solid-state radiation detectors for active personal dosimetry and radiations source tracking

    Talpalariu, Corneliu; Talpalariu, Jeni; Matei, Corina; Lita, Ioan; Popescu, Oana

    2010-01-01

    We report on the design of the readout electronics using PIN diode radiation detector of 5 mm thickness for nuclear safety and active personal dosimetry. Our effort consisted in designing and fabricating the electronics to reflect the needs of gamma radiations dosimetry and hybrids PIN diode arrays for charged particle detectors. We report results obtained during testing and characterizing the new devices in gamma fields, operating at room temperature. There were determined the energy spectrum resolution, radiation hardness and readout rate. Also, data recording methods and parallel acquisition problems from a transducer matrix are presented. (authors)

  5. Radiation heat transfer model using Monte Carlo ray tracing method on hierarchical ortho-Cartesian meshes and non-uniform rational basis spline surfaces for description of boundaries

    Kuczyński Paweł

    2014-06-01

    Full Text Available The paper deals with a solution of radiation heat transfer problems in enclosures filled with nonparticipating medium using ray tracing on hierarchical ortho-Cartesian meshes. The idea behind the approach is that radiative heat transfer problems can be solved on much coarser grids than their counterparts from computational fluid dynamics (CFD. The resulting code is designed as an add-on to OpenFOAM, an open-source CFD program. Ortho-Cartesian mesh involving boundary elements is created based upon CFD mesh. Parametric non-uniform rational basis spline (NURBS surfaces are used to define boundaries of the enclosure, allowing for dealing with domains of complex shapes. Algorithm for determining random, uniformly distributed locations of rays leaving NURBS surfaces is described. The paper presents results of test cases assuming gray diffusive walls. In the current version of the model the radiation is not absorbed within gases. However, the ultimate aim of the work is to upgrade the functionality of the model, to problems in absorbing, emitting and scattering medium projecting iteratively the results of radiative analysis on CFD mesh and CFD solution on radiative mesh.

  6. Stanford Synchrotron Radiation Laboratory 1992 activity report

    Cantwell, K.

    1993-01-01

    Under SLAC's supervision, the SPEAR ring and injector system were operated for the first time in a truly dedicated mode for user experimentation. In October, SSRL became a division of SLAC. With that organizational change, SSRL became fully responsible for the operation, maintenance and improvement of SPEAR and its injection accelerators. At the same time, other radiation sources were studied. Free electron lasers providing enormous peak brightnesses and time average brightnesses about two orders of magnitude greater than the machines presently being constructed or commissioned were the object of one line of analysis. Ultra-short pulse beams at lower photons energies were also studied. These, as well, are described in Chapter 2. Significant gains were also made on the beam lines. Perhaps the most dramatic was the introduction of YB 66 crystals into the Jumbo monochromator, as described in Chapter 3. Looking to the future, SSRL held a workshop on Fourth Generation Light Sources in February and two workshops in conjunction with the Users Meeting. The impact of the high quality running is demonstrated by the many high quality experimental programs performed on SPEAR during the year. These are described in Chapter 6

  7. Facility Activity Inference Using Radiation Networks

    Rao, Nageswara S. [ORNL; Ramirez Aviles, Camila A. [ORNL

    2017-11-01

    We consider the problem of inferring the operational status of a reactor facility using measurements from a radiation sensor network deployed around the facility’s ventilation off-gas stack. The intensity of stack emissions decays with distance, and the sensor counts or measurements are inherently random with parameters determined by the intensity at the sensor’s location. We utilize the measurements to estimate the intensity at the stack, and use it in a one-sided Sequential Probability Ratio Test (SPRT) to infer on/off status of the reactor. We demonstrate the superior performance of this method over conventional majority fusers and individual sensors using (i) test measurements from a network of 21 NaI detectors, and (ii) effluence measurements collected at the stack of a reactor facility. We also analytically establish the superior detection performance of the network over individual sensors with fixed and adaptive thresholds by utilizing the Poisson distribution of the counts. We quantify the performance improvements of the network detection over individual sensors using the packing number of the intensity space.

  8. Radiation protection activities around the CERN accelerators

    Silari, M.

    1998-01-01

    In 1997 the physics programme of the SPS and LEP was seriously affected by a fire in one of the surface building of the SPS; the incident caused a delay in the LEP start-up, an interruption of several weeks in the SPS fixed-target programme, and the cancellation of the lead ion run for 1997. The consequences for the experiments were, nevertheless, kept to a minimum thanks to the excellent performance of the accelerators. The neutrino experiments even accumulated a record intensity. Experiments at the ISOLDE facility benefited from 315 shifts instead of 200 as originally scheduled, and new experiments started measuring the properties of unstable elements which play a crucial role in the stars. LEP also reached record energy and luminosity in 1997. Measurements of synchrotron radiation in the LEP tunnel were repeated at the new energy value of 92 GeV, to comply with the demands of the INB procedure. Following the end of operation of ACOL and LEAR in December 1996, decommissioning of the Antiproton Accumulator and transformation of the Antiproton Collector into the Antiproton Decelerator started. Experiments in the South Hall were dismantled during the year and the hall will be used partly as a storage area for radioactive components and partly as a test area

  9. Spatial distribution of trace metals in water resources impacted by PGM activities

    Walters, Chavon R

    2012-05-01

    Full Text Available the aquatic environment from natural and anthropogenic sources (such as industrial effluents and mining wastes). Trace metals can accumulate in fish (which are often at the top of the aquatic food chain) either through water or the food chain (1), and metals...

  10. The Sensory Nature of Episodic Memory: Sensory Priming Effects Due to Memory Trace Activation

    Brunel, Lionel; Labeye, Elodie; Lesourd, Mathieu; Versace, Remy

    2009-01-01

    The aim of this study was to provide evidence that memory and perceptual processing are underpinned by the same mechanisms. Specifically, the authors conducted 3 experiments that emphasized the sensory aspect of memory traces. They examined their predictions with a short-term priming paradigm based on 2 distinct phases: a learning phase consisting…

  11. Trace element characterization of Indian vegetarian diet and its constituents by instrumental neutron activation analysis

    Singh, V.K.N.; Garg, A.N.; Burte, P.P.

    1995-01-01

    Nutritive trace elements have been determined in a typical vegetarian diet and its various components. A hospital diet, pulses and vegetables have been characterised for 18 elements. Daily intake of elements have been compared with the International diet standards. (author). 5 refs., 1 tab

  12. Determination of trace lithium in uranium compounds by adsorption on activated alumina using a micro-column method.

    Luo, Ming-Biao; Li, Bo-Ping; Yang, Zhi; Liu, Wei; Sun, Yu-Zhen

    2008-08-01

    A novel method using a micro-column packed with active alumina as solid phase was proposed for separation of trace lithium from uranium compounds prior to determination. The method is based on a preliminary chromatographic separation of the total amount of uranium. This separation involves passing the solution containing sodium carbonate through active alumina and then eluting the trace lithium retained by the solid phase with a solution of sulfuric acid. Two modes, off-line and on-line micro-column preconcentration, were performed. In conjunction with atomic absorption spectrometry, this on-line preconcentration technique allows a determination of lithium at 10(-9) level. Both off-line and on-line mode operation conditions were investigated in separation and determination of trace lithium by micro-column method (length of column bed, flow rate, etc.). The adsorption capacity of activated alumina was found to be 343 microg g(-1) for lithium. Under the optimal operation condition, the detection limit (DL) of on-line preconcentration corresponding to three times the standard deviation of the blank (S/N = 3) was found to be 1.3 ng mL(-1) and the RSD of this method is 3.32% (n = 5). The on-line calibration graph was linear over the range 20 - 200 ng mL(-1). A good preconcentration factor 820 was achieved by experiment under the on-line mode. The developed method was applied to the analysis of trace lithium in nuclear grade uranium compounds.

  13. Radiation activation of transcription factors in mammalian cells

    Kraemer, M.; Stein, B.; Mai, S.; Kunz, E.; Koenig, H.; Ponta, H.; Herrlich, P.; Rahmsdorf, H.J.; Loferer, H.; Grunicke, H.H.

    1990-01-01

    In mammalian cells radiation induces the enhanced transcription of several genes. The cis acting elements in the control region of inducible genes have been delimited by site directed mutagenesis. Several different elements have been found in different genes. They do not only activate gene transcription in response to radiation but also in response to growth factors and to tumor promoter phorbol esters. The transcription factors binding to these elements are present also in non-irradiated cells, but their DNA binding activity and their transactivating capability is increased upon irradiation. The signal chain linking the primary radiation induced signal (damaged DNA) to the activation of transcription factors involves the action of (a) protein kinase(s). (orig.)

  14. Radiation protection activities around the CERN accelerators

    Forkel-Wirth, D.; Silari, M.

    1999-01-01

    As planned, the PS complex started up at the end of March 1998. The machines worked smoothly and the availability of the beams reached from 90% up to 96%. New record intensities were achieved for the 14 GeV/c protons for the SPS fixed-target operation and for the Pb 53+ ions. The year 1998 saw the PS complex busy with the transformation of the Antiproton Accumulator (ACOL) into the Antiproton Decelerator (AD). This project is almost finished and the first test beams of protons have already been successfully decelerated in the machine. It is envisaged that the physicists will receive a 100 MeV antiproton beam from October 1999 onwards. Major modifications of the East Hall were required due to the installation of the DIRAC experiment, some test facilities for secondary particles used by LHC experimental groups, and an irradiation area (IRRAD1) for radiation hardness tests of LHC components. The first beams to experimental areas of the East Hall were already sent from July 1998 onwards. The ISOLDE mass separator delivered 275 shifts of radioactive beams of high quality to its user community. The SPS fixed-target programme lasted from 1 April to 30 November. The successful start-up of the accelerators for both the proton and lead-ion periods was followed by stable machine running and by record intensities. The year 1998 marked the end of the operation of the neutrino beam. The dismantling of CHORUS began before the end of the year, to be followed by that of the NOMAD experiment early in 1999

  15. Application of neutron activation analysis to trace element determinations in lung samples

    Rocero, Sizue Ota

    1992-01-01

    The purpose of this work was to apply the instrumental neutron activation analysis method to determine trace elements in lung samples from smokers and non smokers. Samples of lung tissues and lymph nodes from pulmonary hilum analyzed were collected from autopsies by researchers from the Medicine College of the University of Sao Paulo, SP, Brazil. Adequate conditions for preparation and analysis of samples were previously established. The preparation of samples consisted of homogenization, lyophilization and sterilization in 60 Co source. The samples and standards were irradiated in the IEA-R1 reactor under thermal neutron flux of 3.7 x 10 11 n.cm -2 .s -1 for 30 min to determine Cl, K, Mn and Na and for 16 h under flux of 10 19 n.cm -2 .s -1 for the determination of Au, Br, Ce, Co, Cr, Cs, Eu, Fe, Hf, La, Rb, Sb, Sc, Se, Th and Zn. The counting were carried out with a hiperpure (ge) detector connected to a 4096 channels analyzer and a microcomputer. the results obtained for lung sample analyses indicated a good reproducibility of the method for most of the elements determined with relative standard deviations lower than 10.5%. The accuracy of the method was evaluated by analyzing reference materials such as IAEA Animal Muscle H-4, NIST Bovine Liver 1577a, IUPAC Bowen's Kale and NIES Vehicle Exhaust Particulates. The results obtained from these analyzes agreed with the values of the literature for several elements with relative errors less than 20%. Less precise and accurate results were obtained for elements with concentrations at the Mup/Kg levels. Elemental concentrations obtained in the lung tissue analyses were within the range of reference values for normal subjects presented in the literature, except for the Cl concentrations for non smokers, Hf in both groups and Sb for the smokers. By comparing results obtained for lung samples from smokers and non smokers, the concentrations of Ce, Cr and Sb were higher in lungs from smokers and the others elements were

  16. Predicting trace organic compound breakthrough in granular activated carbon using fluorescence and UV absorbance as surrogates.

    Anumol, Tarun; Sgroi, Massimiliano; Park, Minkyu; Roccaro, Paolo; Snyder, Shane A

    2015-06-01

    This study investigated the applicability of bulk organic parameters like dissolved organic carbon (DOC), UV absorbance at 254 nm (UV254), and total fluorescence (TF) to act as surrogates in predicting trace organic compound (TOrC) removal by granular activated carbon in water reuse applications. Using rapid small-scale column testing, empirical linear correlations for thirteen TOrCs were determined with DOC, UV254, and TF in four wastewater effluents. Linear correlations (R(2) > 0.7) were obtained for eight TOrCs in each water quality in the UV254 model, while ten TOrCs had R(2) > 0.7 in the TF model. Conversely, DOC was shown to be a poor surrogate for TOrC breakthrough prediction. When the data from all four water qualities was combined, good linear correlations were still obtained with TF having higher R(2) than UV254 especially for TOrCs with log Dow>1. Excellent linear relationship (R(2) > 0.9) between log Dow and the removal of TOrC at 0% surrogate removal (y-intercept) were obtained for the five neutral TOrCs tested in this study. Positively charged TOrCs had enhanced removals due to electrostatic interactions with negatively charged GAC that caused them to deviate from removals that would be expected with their log Dow. Application of the empirical linear correlation models to full-scale samples provided good results for six of seven TOrCs (except meprobamate) tested when comparing predicted TOrC removal by UV254 and TF with actual removals for GAC in all the five samples tested. Surrogate predictions using UV254 and TF provide valuable tools for rapid or on-line monitoring of GAC performance and can result in cost savings by extended GAC run times as compared to using DOC breakthrough to trigger regeneration or replacement. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. A new method based on low background instrumental neutron activation analysis for major, trace and ultra-trace element determination in atmospheric mineral dust from polar ice cores

    Baccolo, Giovanni, E-mail: giovanni.baccolo@mib.infn.it [Graduate School in Polar Sciences, University of Siena, Via Laterina 8, 53100, Siena (Italy); Department of Environmental Sciences, University of Milano-Bicocca, P.zza della Scienza 1, 20126, Milano (Italy); INFN, Section of Milano-Bicocca, P.zza della Scienza 3, 20126, Milano (Italy); Clemenza, Massimiliano [INFN, Section of Milano-Bicocca, P.zza della Scienza 3, 20126, Milano (Italy); Department of Physics, University of Milano-Bicocca, P.zza della Scienza 3, 20126, Milano (Italy); Delmonte, Barbara [Department of Environmental Sciences, University of Milano-Bicocca, P.zza della Scienza 1, 20126, Milano (Italy); Maffezzoli, Niccolò [Centre for Ice and Climate, Niels Bohr Institute, Juliane Maries Vej, 30, 2100, Copenhagen (Denmark); Nastasi, Massimiliano; Previtali, Ezio [INFN, Section of Milano-Bicocca, P.zza della Scienza 3, 20126, Milano (Italy); Department of Physics, University of Milano-Bicocca, P.zza della Scienza 3, 20126, Milano (Italy); Prata, Michele; Salvini, Andrea [LENA, University of Pavia, Pavia (Italy); Maggi, Valter [Department of Environmental Sciences, University of Milano-Bicocca, P.zza della Scienza 1, 20126, Milano (Italy); INFN, Section of Milano-Bicocca, P.zza della Scienza 3, 20126, Milano (Italy)

    2016-05-30

    Dust found in polar ice core samples present extremely low concentrations, in addition the availability of such samples is usually strictly limited. For these reasons the chemical and physical analysis of polar ice cores is an analytical challenge. In this work a new method based on low background instrumental neutron activation analysis (LB-INAA) for the multi-elemental characterization of the insoluble fraction of dust from polar ice cores is presented. Thanks to an accurate selection of the most proper materials and procedures it was possible to reach unprecedented analytical performances, suitable for ice core analyses. The method was applied to Antarctic ice core samples. Five samples of atmospheric dust (μg size) from ice sections of the Antarctic Talos Dome ice core were prepared and analyzed. A set of 37 elements was quantified, spanning from all the major elements (Na, Mg, Al, Si, K, Ca, Ti, Mn and Fe) to trace ones, including 10 (La, Ce, Nd, Sm, Eu, Tb, Ho, Tm, Yb and Lu) of the 14 natural occurring lanthanides. The detection limits are in the range of 10{sup −13}–10{sup −6} g, improving previous results of 1–3 orders of magnitude depending on the element; uncertainties lies between 4% and 60%. - Highlights: • A new method based on neutron activation for the multi-elemental characterization of atmospheric dust entrapped in polar ice cores is proposed. • 37 elements were quantified in μg size dust samples with detection limits ranging from 10{sup −13} to 10{sup −6} g. • A low background approach and a clean analytical protocol improved INAA performances to unprecedented levels for multi-elemental analyses.

  18. TRACING MULTIPLE GENERATIONS OF ACTIVE GALACTIC NUCLEUS FEEDBACK IN THE CORE OF ABELL 262

    Clarke, T. E.; Kassim, N. E.; Blanton, E. L.; Anderson, L. D.; Douglass, E. M.; Sarazin, C. L.; Gopal-Krishna

    2009-01-01

    We present new radio and X-ray observations of Abell 262. The X-ray residual image provides the first evidence of an X-ray tunnel in this system while the radio data reveal that the central radio source is more than three times larger than previously known. We find that the well-known cluster-center S-shaped radio source B2 0149+35 is surrounded by extended emission to the east and southwest. The south-western extension is cospatial with the X-ray tunnel seen in our new Chandra images while the eastern extension shows three clumps of emission with the innermost coincident with a faint X-ray cavity. The outer two eastern radio extensions are coincident with a newly detected X-ray depression. We use the projected separation of the emission regions to estimate a lower limit of τ rep = 28 Myr to the outburst repetition timescale of the central active galactic nucleus (AGN). The total energy input into the cluster over multiple outburst episodes is estimated to be 2.2 x 10 58 erg, more than an order of magnitude larger than previously thought. The total AGN energy output determined from our new observations shows that the source should be capable of offsetting radiative cooling over several outburst episodes.

  19. Prevalence of Pulmonary Tuberculosis among Household Contacts in Hyderabad, Sindh: Active Contact Tracing in Children with Tuberculosis

    Sheikh, M.A.; Shah, S.A.A.

    2017-01-01

    Background: Tuberculosis (TB) in children is clearly linked to TB in adults therefore active household contact tracing is an important method of early diagnosis and treatment particularly in high-TB-burden countries. Objectives: To estimate the prevalence of TB among household contacts of children suffering from tuberculosis using active contact tracing and linking them to TB program for treatment. Subjects and Methods: A total of 125 children suffering from active tuberculosis (index cases)aged 12 years or less were randomly selected from the outpatient department of a tertiary care hospital of Hyderabad. Using their home address, all house hold members of the index cases (sharing one kitchen) were identified. The households were visited by a team including a doctor and the supported staff and were screened for TB using history, physical examination, sputum for AFB and X-ray of chest. Clinical suspects were divided in to two populations, equal to or less than 12 years of age and greater than this age. All suspected cases were brought to outpatient's department of the hospital where children were examined and diagnosed by pediatrician and adults were examined by the pulmonologist. Results: There were 125 children and 1365 household members. Prevalence of active TB in adult household contacts was 8.1 percent and among children was 5.7 percent. Mother, father, grand parents or siblings were the source of disease spread in children. Family history of TB was present in 95 percent (pulmonary 78 percent, extra-pulmonary 22 percent). Conclusion: Tuberculosis in children is mostly spreading from household member hence deeply required to undertake active contact tracing in each new case that is diagnosed or being treated. Policy message: National and Provincial TB programs should advocate and undertake active screening of all household contacts of all TB cases. (author)

  20. Trace analysis measurements in high-purity aluminium by means of radiochemical neutron and proton activation analysis

    Egger, K.P.

    1987-01-01

    The aim of the study consisted in the development of efficient radiochemical composite processes and activation methods for the multi-element determination of traces within the lower ng range in high-purity aluminium. More than 50 elements were determined with the help of activation with reactor neutrons; the selective separation of matrix activity (adsorption with hydrated antimony pentoxide) led to a noticeable improvement of detectability, as compared with instrumental neutron activation analysis. Further improvements were achieved with the help of radiochemical group separations in ion exchangers or with the help of the selective separation of the pure beta-emitting elements. Over 20 elements up to high atomic numbers were determined by means of activating 13 MeV protons and 23 Me protons. In this connection, improvements of the detection limit by as a factor of 10 were achieved with radiochemical separation techniques, as compared with pure instrumental proton activation analysis. (RB) [de

  1. Analysis and characterization of trace elements in shale oil and shale oil products by instrumental neutron activation analysis. Master's thesis

    Shaw, P.

    1978-12-01

    Trace elements and their mobilization constitute an important consideration in the development of new fossil fuel technologies. Shale oil produced by in situ retorting of oil shale is an alternative fossil energy source. This study deals with the analysis of trace elements in various shale oil products using instrumental neutron activation analysis (INAA). INAA offers several advantages for those elements for which it is applicable. The greatest advantage is the lack of sample preparation prior to analysis, which greatly simplifies the process and prevents sample contamination. The elements for which analyses are reported in this study are aluminum, antimony, arsenic, bromine, cerium, chlorine, chromium, cobalt, copper, gallium, gold, iodine, iron, manganese, mercury, molybdenum, potassium, selenium, sodium, sulfur, tungsten, vanadium, and zinc

  2. Trace elements in 11 fruits widely-consumed in the USA as determined by neutron activation analysis

    Michenaud-Rague, A.; Robinson, S.; Landsberger, S.

    2012-01-01

    While there is a lot of information on the elemental content of food for nutritional and pollution studies, the analysis of fruits has received little attention. We have investigated 11 commonly eaten fruits for their trace and minor element constituents by neutron activations including thermal and epithermal neutron activation analysis. Our results revealed that both blueberries and strawberries had the most of top two highest elemental concentrations followed by raspberries, oranges and mango. Bananas, grapes, plums, apples, pears, and cherries had the fewest or none of the most elevated elemental concentrations. (author)

  3. Oesophageal cancer in the Transkei. Determination of trace element concentrations in selected plant material by instrumental neutron activation analysis

    Renan, M.J.; Drennan, B.D.; Keddy, R.J.; Sellschop, J.P.F.

    1979-01-01

    The results of the analysis by instrumental neutron activation for the concentration of trace elements in plant materials from certain areas in the Transkei region of southern Africa are presented. These areas are selected for their characteristic high or low incidence of carcinoma of the oesophagus. To broaden the suite of elements for which analysed and to overcome some of the limitations of neutron activation analysis, certain other nuclear analyses and methods are suggested which, if utilized, would increase the number of elements determined, and so improve the information available. (author)

  4. Temporal variability of the quality of Taraxacum officinale seed progeny from the East-Ural radioactive trace: is there an interaction between low level radiation and weather conditions?

    Pozolotina, Vera N; Antonova, Elena V

    2017-03-01

    The multiple stressors, in different combinations, may impact differently upon seed quality, and low-level doses of radiation may enhance synergistic or antagonistic effects. During 1991-2014 we investigated the quality of the dandelion (Taraxacum officinale s.l.) seed progeny growing under low-level radiation exposure at the East-Ural Radioactive Trace (EURT) area (result of the Kyshtym accident, Russia), and in plants from areas exposed to background radiation. The viability of the dandelion seed progeny was assessed according to chronic radiation exposure, accounting for the variability of weather conditions among years. Environmental factors (temperature, precipitation, and their ratio in different months) can modify the radiobiological effects. We found a wide range of possible responses to multiple stressors: inhibition, stimulation, and indifferent effects in different seasons. The intraspecific variability of the quality of dandelion seed progeny was greatly increased under conditions of low doses of chronic irradiation. Temperature was the most significant factor for seed progeny formation in the EURT zone, whereas the sums of precipitation and ratios of precipitation to temperature dominantly affected organisms from the background population.

  5. Contribution of neutron activation analysis and radioanalytical techniques to trace element speciation in environmental analysis

    Gallorini, M.; Orvini, E.; Sabbioni, E.; Pietra, R.

    1984-01-01

    The feasibility of the NAA in contributing to trace element speciation in environmental and biological samples is shown by a few selected applications. They are: (i) the determination of different species of vanadium, arsenic and selenium in freshwater. The pre-irradiation treatments in which the different chemical species are selectively isolated are critically evaluated. Problems arising from possible contaminations or losses and from blanks are discussed; (ii) the use of NAA in metallobiochemical speciation once biochemical methods of cellular fractionation for the isolation of metallobiocomplexes are developed. Examples concern the biochemical speciation of vanadium in human blood and the development of a method for speciation of inorganic and organic arsenic compounds in biological samples. The use of radioanalytical techniques in developing the separation procedures of different trace metal chemical and biochemical species is also briefly discussed. 24 references, 5 figures, 4 tables

  6. Determination of several trace elements in Chinese herbs with epithermal neutral activation analysis

    Chen, Chien-Yi; Chang Lai, Sheng-Pin

    2002-01-01

    For purpose of medication and health, Chinese herbs have been long adopted throughout oriental communities. Thus, more than ten trace elements in herbal medicines that are frequently consumed by children in central Taiwan were analyzed herein to explore the importance of various herbs. These elements are considered beneficial to human health in many folds. INAA was applied to determine the concentrations of elements as Al, Cl and Sc, while ENAA analyzed As, Cd, Mn, and Sb in this work. Among various local herbs, the elemental concentrations varied from 10 4 to 10 -3 μg/g. The experimental results suggest that the ENAA method can be applied successfully to analyze trace elements of As, Cd, Mn, and Sb in herbs. Yet, thirteen elements were verified, and a quantified index AT was introduced to help classifying the elements. The ATs in various Chinese herbs are also discussed herein and the accuracy is in excellent agreement with values reported in previously published data. (author)

  7. Assessment of daily intake of major and trace elements by inhabitants of potential radiation protection of greater Cairo area, Egypt

    Ramadan, A.B.

    2005-01-01

    Concentrations of K, Ca, U, Th, Cs, Sr, I, Al, Cd, Cu, Mn, Pb, Ni and Cr were determined in vegetables, common foodstuffs and some animal products consumed by adult inhabitants of Greater Cairo Area. Some of these elements have chemical and biological similarity to some of the radionuclides abundantly encountered during nuclear power production and therefore data on these elements could provide important information on their biokinetic behavior. A total of 120 samples were analyzed using Neutron Activation Analysis (NAA) and Atomic Absorption Spectrometry (AAS). Generally, highest contributions for the intake of micro nutrients (Cu, Mn and Ni) arise from broad bean, rice and wheat flour consumption. Meat, milk, eggs and some vegetables are the major sources of K, Ca, U, Th, Cs, Al, Cd and Pb. The medium daily intake for the adult inhabitants of greater Cairo area was found to be 1.98 g of K, 0.54 mg of Ca, 1.14 fig of U, 0.8 μg of Th, 5.2μg of Cs, 1.3 mg of Sr, 105 μg of 1, 3.2 mg of Mn, 0.9 mg of Cu, 5.7 mg of Al, 5, 2 x 10 -2 mg of Pb, 2.1x10 -3 mg of Cd, 7.7x10 -2 mg of Ni and 2.1 x 10 -2 mg of Cr. The lower daily intake of Ca, Th, Cs and I by adult inhabitants of greater Cairo area could be due to the significantly lower consumption of milk and milk products, which are rich in these elements. The significantly lower intake of calcium by adult inhabitants of greater Cairo area may lead to higher uptake of radiostrontium and could result in higher internal radiation dose. The use of highly sensitive and reliable analytical methods resulted in accurate assessment of the values recorded for thorium and uranium suggested that radiation dose from their ingestion at natural background levels, is likely to be lower than those included in ICRP data. Concerning micro nutrients, the recommended values of daily intake of Cu and Mn are conveniently supplied by the common diet; however for Cr is lower than the recommended daily allowance. Due to high metals concentrations

  8. Activities of the Institute of Radiation Protection and Dosimetry on radiation overexposure analysis - results from 1994 to 1997

    Silva, Francisco C.A. da; Ramalho, Adriana

    1999-01-01

    Since 1985 the Institute of Radiation Protection and Dosimetry has operated a service carried out by a multi-disciplinary Group called Radiation Overexposure analysis Group - GADE. It is composed of specialists in radiation protection and dosimetry and has the main objective of taking coordinated actions on radiation overexposure cases. This paper shows mainly the results got from 1984 to 1997 with the methodology used. It was observed that the cases are falling down due to radiation protection activities in the installation. (author)

  9. (U) Second-Order Sensitivity Analysis of Uncollided Particle Contributions to Radiation Detector Responses Using Ray-Tracing

    Favorite, Jeffrey A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-30

    The Second-Level Adjoint Sensitivity System (2nd-LASS) that yields the second-order sensitivities of a response of uncollided particles with respect to isotope densities, cross sections, and source emission rates is derived in Refs. 1 and 2. In Ref. 2, we solved problems for the uncollided leakage from a homogeneous sphere and a multiregion cylinder using the PARTISN multigroup discrete-ordinates code. In this memo, we derive solutions of the 2nd-LASS for the particular case when the response is a flux or partial current density computed at a single point on the boundary, and the inner products are computed using ray-tracing. Both the PARTISN approach and the ray-tracing approach are implemented in a computer code, SENSPG. The next section of this report presents the equations of the 1st- and 2nd-LASS for uncollided particles and the first- and second-order sensitivities that use the solutions of the 1st- and 2nd-LASS. Section III presents solutions of the 1st- and 2nd-LASS equations for the case of ray-tracing from a detector point. Section IV presents specific solutions of the 2nd-LASS and derives the ray-trace form of the inner products needed for second-order sensitivities. Numerical results for the total leakage from a homogeneous sphere are presented in Sec. V and for the leakage from one side of a two-region slab in Sec. VI. Section VII is a summary and conclusions.

  10. Some human activities to decrease public radiation dose

    Pan Ziqiang; Guo Minqiang

    1994-01-01

    The necessity of studying the variations in radiation levels from the balance viewpoint is discussed. Some human activities may increase, while others may decrease, radiation dose to population. In 1988, China's investigation showed that travel by air caused a raise of population collective dose by 3.6 x 10 1 man·Sv, while travel by ship, train and vehicle lead to a drop of 5.36 x 10 2 man·Sv, and that dwellings of coal cinder brick decreased collective dose by 3.5 x 10 3 man·Sv, while buildings of reinforced concrete structure increased collective dose by 3.7 x 10 3 man·Sv. It is inadequate to only study those activities which may increase radiation levels

  11. Potential role of peroxisome proliferator activated receptor gamma activation on serum visfatin and trace elements in high fat diet induced type 2 diabetes mellitus.

    Tabassum, Arshia; Zaidi, Syeda Nuzhat Fatima; Yasmeen, Kausar; Mahboob, Tabassum

    2018-07-15

    Electrolytes and trace elements dysregulation play an important role in the progression of obesity and diabetes complications. The present study was designed to evaluate the insulin sensitizing effects of peroxisomes proliferators activated receptor gamma (PPAR-γ) agonist on trace elements in obesity induced type 2 diabetes mellitus and correlate with serum visfatin. Wistar rats were categorized into five groups. Group I served as control; Group II fed on high fat diet (HFD); Group III fed on HFD and treated with rosiglitazone (3 mg/kg) for 7 days; Group IV were T2DM rats induce by HFD and low dose of streptozotocin (i.p. 35 mg/kg); Group V was T2DM rats treated with rosiglitazone (3 mg/kg) for 7 days. Serum and tissues electrolytes levels and renal, hepatic and cardiac tissues trace elements were estimated by flame photometer and atomic absorption spectroscopy. Serum visfatin was estimated by ELISA. Pearson correlations were analyzed among fasting blood glucose (FBG), serum visfatin and tissues trace elements. Results of the current study showed hyponatremia, hyperkalemia, hypomagnesemia and hypercalcemia in HFD and T2DM groups. HFD and T2DM also showed elevated copper and iron levels; however, zinc and selenium levels were decreased. Rosiglitazone treatment increased the insulin sensitization and altered these changes. A Strong association was observed among FBG, serum visfatin and trace elements levels of HFD and T2DM. Obesity and diabetes mellitus disturbed visfatin, electrolytes and trace elements homeostasis. Rosiglitazone treatment restored these changes. The results of the study could serve as a basis for further studies for the prevention of diabetic complications. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Biological activities of radiation-degraded carrageenan

    Relleve, Lorna; Dela Rosa, Alumanda; ABAD, Lucille; Aranilla, Charito; Aliganga, Anne Kathrina [Philippine Nuclear Research Institute, Quezon City (Philippines); Yoshii, Fumio; Kume, Tamikazu; Nagasawa, Naotsugu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2001-03-01

    Carrageenans were irradiated in solid state to doses 50-1000 kGy in air at ambient temperature. Changes in their molecular weight and functional properties with respect to their FT-IR and UV spectra were evaluated. Irradiation of carrageenans resulted in a rapid decrease of molecular weight indicating main chain scission in their polymeric structures. Formations of some compounds were evident by new absorption peaks in their UV and FT-IR spectra and quantitative analyses of the FT-IR spectra which, in addition, support that there is a breakdown in the carrageenan structure. Irradiated carrageenans were investigated for their plant growth-promoting activity. Carrageenans were added to the nutrient solutions for rice seedlings under non-circulating hydroponics cultivation. Irradiated carrageenan induced weight gain in treated rice seedlings. Maximum weight gain was obtained with KC irradiated at 100 kGy while treatment with IC at 500 kGy. IC exhibited less growth promoting properties than KC. The growth of fungi on the roots disappeared with treatment of IC and KC irradiated at 500 kGy. Growth promotion of some leafy vegetables was also observed with application of degraded KC. The carrageenan molecule has been broken down to smaller molecule (s) or compound (s) that can be absorbed effectively as nourishment factors and anti-microbial agents by plants. (author)

  13. Biological activities of radiation-degraded carrageenan

    Relleve, Lorna; Dela Rosa, Alumanda; ABAD, Lucille; Aranilla, Charito; Aliganga, Anne Kathrina; Yoshii, Fumio; Kume, Tamikazu; Nagasawa, Naotsugu

    2001-01-01

    Carrageenans were irradiated in solid state to doses 50-1000 kGy in air at ambient temperature. Changes in their molecular weight and functional properties with respect to their FT-IR and UV spectra were evaluated. Irradiation of carrageenans resulted in a rapid decrease of molecular weight indicating main chain scission in their polymeric structures. Formations of some compounds were evident by new absorption peaks in their UV and FT-IR spectra and quantitative analyses of the FT-IR spectra which, in addition, support that there is a breakdown in the carrageenan structure. Irradiated carrageenans were investigated for their plant growth-promoting activity. Carrageenans were added to the nutrient solutions for rice seedlings under non-circulating hydroponics cultivation. Irradiated carrageenan induced weight gain in treated rice seedlings. Maximum weight gain was obtained with KC irradiated at 100 kGy while treatment with IC at 500 kGy. IC exhibited less growth promoting properties than KC. The growth of fungi on the roots disappeared with treatment of IC and KC irradiated at 500 kGy. Growth promotion of some leafy vegetables was also observed with application of degraded KC. The carrageenan molecule has been broken down to smaller molecule (s) or compound (s) that can be absorbed effectively as nourishment factors and anti-microbial agents by plants. (author)

  14. Active electromagnetic invisibility cloaking and radiation force cancellation

    Mitri, F. G.

    2018-03-01

    This investigation shows that an active emitting electromagnetic (EM) Dirichlet source (i.e., with axial polarization of the electric field) in a homogeneous non-dissipative/non-absorptive medium placed near a perfectly conducting boundary can render total invisibility (i.e. zero extinction cross-section or efficiency) in addition to a radiation force cancellation on its surface. Based upon the Poynting theorem, the mathematical expression for the extinction, radiation and amplification cross-sections (or efficiencies) are derived using the partial-wave series expansion method in cylindrical coordinates. Moreover, the analysis is extended to compute the self-induced EM radiation force on the active source, resulting from the waves reflected by the boundary. The numerical results predict the generation of a zero extinction efficiency, achieving total invisibility, in addition to a radiation force cancellation which depend on the source size, the distance from the boundary and the associated EM mode order of the active source. Furthermore, an attractive EM pushing force on the active source directed toward the boundary or a repulsive pulling one pointing away from it can arise accordingly. The numerical predictions and computational results find potential applications in the design and development of EM cloaking devices, invisibility and stealth technologies.

  15. New radiative transfer models for obscuring tori in active galaxies

    van Bemmel, IM; Dullemond, CP

    Two-dimensional radiative transfer is employed to obtain the broad-band infrared spectrum of active galaxies. In the models we vary the geometry and size of the obscuring medium, the surface density, the opacity and the grain size distribution. Resulting spectral energy distributions are constructed

  16. Rights versus labour privileges for ionizing radiation exposure activities

    Borges, Jose Carlos

    1996-01-01

    The present panorama of brazilian legislation concerning activities in which (may) occurs exposure to ionizing radiations, involves several incoherencies and privileges, as a consequence of legal rights generated from labor principles which have no social or scientific embasement. In this study, several legal labor topics are analysed and a new doutrinary context is proposed. (author)

  17. Evaluation of essential trace elements in preterm and full term milk and childhood formulas by neutron activation analysis

    Santos, Paola de Souza

    2009-01-01

    Many studies have emphasized the need of trace elements during infancy and their adequate availability in human milk. Deficiency of minor and trace elements can lead to various disorders in infants. During early childhood trace element requirements, are more critical due to faster growth rates. In this study, Ca, Cl, Fe, K, Mg, Mn, Na, Se and Zn were determined in human colostrum samples from mothers of preterm and full-term newborns. Samples were collected by manual expression from the first to the fifth day after birth. After collection, human colostrum samples were frozen and freeze-dried for analyses. Few of the most commonly commercialized were also analyzed. The essential element concentrations were determined in 30 colostrum samples and 17 milk formula brands by Instrumental Neutron Activation Analysis. Multivariate analyses were applied and the results were separated in two clusters. However the separation was not related to the corresponding gestational age. Results of this study showed that the concentration levels of the essential element Ca, K and Na in the milk formula samples analyzed were in agreement with the printed information on the labels. All concentration levels were also within ANVISA and Codex Allimentarius recommended values and thus adequate for infant nutritional needs. (author)

  18. Determination of base-line levels of trace amounts in pulses and spices using neutron activation technique

    Zaidi, J.H.; Arif, M.; Fatima, I.; Qureshi, I.H.

    1993-01-01

    It has been established that essential trace elements are vitally important for biochemical systems, whereas toxic elements if present in relatively higher amounts adversely affect these systems. Trace elements reach the human body mainly through foodstuffs. The different articles contain varying amount of toxic and essential elements. It is therefore necessary to asses the adequacy and safety of the diet by determining the base-line levels of these elements. In continuation of our previous work, some varieties of pulses and spices were analyzed using neutron activation technique. Among the four varieties of pulses lentil (lens esculenta) was found to contain higher amounts of essential elements and lower amounts of toxic elements. The daily intake of essential and toxic elements through pulses was estimated and compared with the suggested values. The estimated intake of essential elements is adequate and that of toxic elements is well below the tolerance limit. In spices cumin and caraway seeds were found to contain relatively higher amounts of essential as well as toxic elements. The studies showed that food spices were additional source of trace element intake. (author)

  19. Removal of trace organic contaminants by a membrane bioreactor-granular activated carbon (MBR-GAC) system.

    Nguyen, Luong N; Hai, Faisal I; Kang, Jinguo; Price, William E; Nghiem, Long D

    2012-06-01

    The removal of trace organics by a membrane bioreactor-granular activated carbon (MBR-GAC) integrated system were investigated. The results confirmed that MBR treatment can be effective for the removal of hydrophobic (log D>3.2) and readily biodegradable trace organics. The data also highlighted the limitation of MBR in removing hydrophilic and persistent compounds (e.g. carbamazepine, diclofenac, and fenoprop) and that GAC could complement MBR very well as a post-treatment process. The MBR-GAC system showed high removal of all selected trace organics including those that are hydrophilic and persistent to biological degradation at up to 406 bed volumes (BV). However, over an extended period, breakthrough of diclofenac was observed after 7320 BV. This suggests that strict monitoring should be applied over the lifetime of the GAC column to detect the breakthrough of hydrophilic and persistent compounds which have low removal by MBR treatment. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  20. Investigation on trace elements in crude oil and organic matter extracted from rocks with instrumental neutron activation analysis

    Ding Zuguo; Chai Zhifang

    1990-01-01

    Solvent extraction, column chromatography and instrumental neutron activation analysis(INAA) have been used to investigate the trace elements in crude oil, organic matter extracted from rocks and their related fractions. With these methods, about 70 crude oil samples from eight different oil fields in China and 6 extracted asphaltene samples of the lower paleozoic from the upper Yangtze region have been analyzed, and about 40 elements of interest have been determined. Those elements include Al, As, Au, Ba, Br, Cl, Co, Cr, Cs, Cu, Fe, Hf, I, Ir, Mg, Mn, Mo, Na, Ni, Rb, Re, S, Sb, Sc, Se, Sr, Th, Zn, V and parts of REE. The experimental results show that the method possesses several advantages, i.e. non-destructive, multi-elements, sensitive, precise and accurate. Without ashing samples, the loss of volatile elements such as Cl, S, Se and Sb are avoided. The column chromatography makes it possible to study the distributions of trace elements in different fractions of crude oil and organic matter extracted. Meanwhile, the characters of trace elements in them have also been discussed

  1. In vitro antiplasmodial activity, macronutrients and trace metals in the medicinal plants: Phyllanthus spp. and Alpinia conchigera Griff.

    Haslinda, M S; Aiyub, Z; Bakar, N K A; Tohar, N; Musa, Y; Abdullah, N R; Ibrahim, H; Awang, K

    2015-03-01

    An antiplasmodial screening of Phyllanthus debilis and Phyllanthus urinaria was carried out. The medicinal plants were extracted and evaluated for in vitro antiplasmodial activity against D10 (chloroquine-sensitive, CQS) and Gombak A (chloroquine-resistant, CQR) strains of Plasmodium falciparum. The methanolic crudes from the soxhlet extraction were active against both strains however, P. urinaria (IC50 8.9 μg/ml with CQR strain) exhibited better anti-malarial activity compared to P. debilis (IC50 12.2 μg/ml with CQR strain). Furthermore, the methanolic crude of P. urinaria obtained by the cold extraction has good anti-malarial activity towards CQS (IC50 4.1 μg/ml). The concentration of macronutrients (calcium and magnesium) and trace metals (copper, manganese, iron and zinc) from three Phyllanthus species i.e. P. debilis Klein ex Wild., Phyllanthus niruri L., P. urinaria L. and Alpinia conchigera Griff. were determined using microwave digestion method and analyzed by Flame Atomic Absorption Spectroscopy. Standard Reference Material 1547 (peach leaves) was used to validate the method throughout this study. The recovery values were in the range of 80% to 120% which were in very good agreement with the certified values. The three Phyllanthus species and leaves of A. conchigera showed the highest concentration of calcium compared to other metals and macronutrients studied. The significant presence of all the important macronutrients and trace metals which are essential for human health and well-being substantiate their use medicinally in traditional practices.

  2. Synoptic Traveling Weather Systems on Mars: Effects of Radiatively-Active Water Ice Clouds

    Hollingsworth, Jeffery; Kahre, Melinda; Haberle, Robert; Urata, Richard

    2017-01-01

    Atmospheric aerosols on Mars are critical in determining the nature of its thermal structure, its large-scale circulation, and hence the overall climate of the planet. We conduct multi-annual simulations with the latest version of the NASA Ames Mars global climate model (GCM), gcm2.3+, that includes a modernized radiative-transfer package and complex water-ice cloud microphysics package which permit radiative effects and interactions of suspended atmospheric aerosols (e.g., water ice clouds, water vapor, dust, and mutual interactions) to influence the net diabatic heating. Results indicate that radiatively active water ice clouds profoundly affect the seasonal and annual mean climate. The mean thermal structure and balanced circulation patterns are strongly modified near the surface and aloft. Warming of the subtropical atmosphere at altitude and cooling of the high latitude atmosphere at low levels takes place, which increases the mean pole-to-equator temperature contrast (i.e., "baroclinicity"). With radiatively active water ice clouds (RAC) compared to radiatively inert water ice clouds (nonRAC), significant changes in the intensity of the mean state and forced stationary Rossby modes occur, both of which affect the vigor and intensity of traveling, synoptic period weather systems.Such weather systems not only act as key agents in the transport of heat and momentum beyond the extent of the Hadley circulation, but also the transport of trace species such as water vapor, water ice-clouds, dust and others. The northern hemisphere (NH) forced Rossby waves and resultant wave train are augmented in the RAC case: the modes are more intense and the wave train is shifted equatorward. Significant changes also occur within the subtropics and tropics. The Rossby wave train sets up, combined with the traveling synoptic period weather systems (i.e., cyclones and anticyclones), the geographic extent of storm zones (or storm tracks) within the NH. A variety of circulation

  3. Activating PTEN by COX-2 inhibitors antagonizes radiation-induced AKT activation contributing to radiosensitization

    Meng, Zhen [Central Laboratory, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Department of Oral & Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Gan, Ye-Hua, E-mail: kqyehuagan@bjmu.edu.cn [Central Laboratory, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Department of Oral & Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China)

    2015-05-01

    Radiotherapy is still one of the most effective nonsurgical treatments for many tumors. However, radioresistance remains a major impediment to radiotherapy. Although COX-2 inhibitors can induce radiosensitization, the underlying mechanism is not fully understood. In this study, we showed that COX-2 selective inhibitor celecoxib enhanced the radiation-induced inhibition of cell proliferation and apoptosis in HeLa and SACC-83 cells. Treatment with celecoxib alone dephosphorylated phosphatase and tensin homolog deleted on chromosome ten (PTEN), promoted PTEN membrane translocation or activation, and correspondingly dephosphorylated or inactivated protein kinase B (AKT). By contrast, treatment with radiation alone increased PTEN phosphorylation, inhibited PTEN membrane translocation and correspondingly activated AKT in the two cell lines. However, treatment with celecoxib or another COX-2 selective inhibitor (valdecoxib) completely blocked radiation-induced increase of PTEN phosphorylation, rescued radiation-induced decrease in PTEN membrane translocation, and correspondingly inactivated AKT. Moreover, celecoxib could also upregulate PTEN protein expression by downregulating Sp1 expression, thereby leading to the activation of PTEN transcription. Our results suggested that COX-2 inhibitors could enhance radiosensitization at least partially by activating PTEN to antagonize radiation-induced AKT activation. - Highlights: • COX-2 inhibitor, celecoxib, could enhance radiosensitization. • Radiation induced PTEN inactivation (phosphorylation) and AKT activation. • COX-2 inhibitor induced PTEN expression and activation, and inactivated AKT. • COX-2 inhibitor enhanced radiosensitization through activating PTEN.

  4. The objectives and activities of the Canadian Radiation Protection Association

    Haynes, M.J.

    1998-01-01

    The Canadian Nuclear Society and the Canadian Radiation Protection Association are working to develop an agreement between the organizations to facilitate working together on issues of common interest. This paper will present the objectives, the organizational structure and major areas of activity of the Canadian Radiation Protection Association. It is a reciprocal presentation of one given earlier this year by Mr. Fred Boyd of the CNS to the CRPA annual conference. The intent is to help the membership of each organization better understand the objectives and interests of the other. (author)

  5. Combination of ray-tracing and the method of moments for electromagnetic radiation analysis using reduced meshes

    Delgado, Carlos; Cátedra, Manuel Felipe

    2018-05-01

    This work presents a technique that allows a very noticeable relaxation of the computational requirements for full-wave electromagnetic simulations based on the Method of Moments. A ray-tracing analysis of the geometry is performed in order to extract the critical points with significant contributions. These points are then used to generate a reduced mesh, considering the regions of the geometry that surround each critical point and taking into account the electrical path followed from the source. The electromagnetic analysis of the reduced mesh produces very accurate results, requiring a fraction of the resources that the conventional analysis would utilize.

  6. The importance of making right knowledge about radiation popular. Activity of 'radiation education forum'

    Matsuura, Tatsuo; Iiri, Yuichi

    2000-01-01

    Radiation and radionuclides are not only indispensable in medical diagnoses and treatments, but are widely used in fundamental researches in various fields and in industry, thus contribute much to humans for elevating the quality of life. Nuclear power production is also playing an important role in saving the nonrenewable natural energy resources, without producing potentially problematic carbon dioxide. However, a majority of people has an excessive concern for radiation and radioactivity even for very minute quantities. This is due to the following three facts: (1) the first use of nuclear energy as the disastrous weapon in 1945 has resulted a profound after-effect in socio-psychological sense especially in Japan, (2) the major accidents of nuclear power plants which occurred in 1980's have been repeatedly reported in mass media with undue sensationalism, and (3) the proposition, that every ray of ionizing radiation may destroy DNA of human cells and is harmful by bringing carcinogenic or hereditary effects, has fixed as a suspicion-free common sense for general public. This proposition has its basis on the recommendation by ICRP of adopting the LNT (linear non-threshold), model even for low dose of radiations comparative with the natural radiation level. Thus the majority of people shows the syndrome of radio phobia'. Because there are so many risks other than radiation in the present day civilization, the extremely severe regulation only of radiation has many social demerits, and it is highly necessary that this situation be improved, by making the correct scientific information popular to the public. As an approach to this goal, a voluntary group, 'Radiation Education Forum', comprised of scientists, schoolteachers, journalists and citizens, has been established in 1994 in Japan, and has continued various types of activities. Because the social education has its basis on the school education, we have focussed our energy mainly for improving the education

  7. Trace elements of coal, coal ashes and fly ashes by activation analysis with shor-lived nuclides

    Boeck, H.; Sarac, I.; Grass, F.

    1981-01-01

    On irradiation with neutrons, some of the interesting trace elements in coal, coal ash and fly ash produce short-lived nuclides which may be determined - together with some of the matrix elements - by activation analysis. This enables the characterization of samples. To find out the distribution of elements in the gaseous or aerosol exhaust of fossil-fired power plants, the authors simulated the combustion in a quartz apparatus containing a cold trap, using the combustion temperature (780 deg C) employed for the standard ash determination. High Se values were found in the cold trap deposits of black coal from Poland. Halogens were also found in the deposits. (authors)

  8. Monitoring of trace-levels of herbicides in the Cachoeira River in Bahia State, Brazil, by neutron activation analysis

    Severo, Maria Isabel; Oliveira, Eduardo; Caribe, Ana Cristina; Revel, Gilles; Oliveira, Arno Heeren

    1995-01-01

    A systematic study was undertaken in order to find out which of the most relevant elements can be determined in water normal conditions by non-destructive neutron activation and a suitable mono standard method. Standardized water from Cachoeira river and croustaceous samples were brought to dryness by freeze-drying and irradiated in quartz at a neutron flux of 10 14 cm -2 s -1 . Trace element contents in quartz ampoules from different origins were determined separately. The following elements were preliminarily identified: Cr, Co, Cu, Br, Sb, Cs, Ce, Nb, Au, Pa, Zn, La, Sm. (author). 10 refs., 2 tabs

  9. Experiments made to separate the trace elements in seawater by extraction and their determination by neutron activation analysis

    Heuss, E.; Lieser, K.H.

    1979-01-01

    The problems of trace element determination in seawater by neutron activation analysis are discussed. Experiments with tri-n-octylphosphinoxide (TOPO) did not bring satisfactory results because of the strong interference of the bremsstrahlung from 32 P. Experiments with oxin at different pH showed that in each case only few elements are extracted in greater amounts. An extraction apparatus is described making possible the extraction of up to 10 l water by 50 ml of an organic solution. Extraction experiments using different complexing agents were satisfactory but the evaporation of the organic phase to dryness for irradiation was difficult. (author)

  10. Evaluation of Forensic DNA Traces When Propositions of Interest Relate to Activities: Analysis and Discussion of Recurrent Concerns

    Biedermann, Alex; Champod, Christophe; Jackson, Graham; Gill, Peter; Taylor, Duncan; Butler, John; Morling, Niels; Hicks, Tacha; Vuille, Joelle; Taroni, Franco

    2016-01-01

    When forensic scientists evaluate and report on the probative strength of single DNA traces, they commonly rely on only one number, expressing the rarity of the DNA profile in the population of interest. This is so because the focus is on propositions regarding the source of the recovered trace material, such as “the person of interest is the source of the crime stain.” In particular, when the alternative proposition is “an unknown person is the source of the crime stain,” one is directed to think about the rarity of the profile. However, in the era of DNA profiling technology capable of producing results from small quantities of trace material (i.e., non-visible staining) that is subject to easy and ubiquitous modes of transfer, the issue of source is becoming less central, to the point that it is often not contested. There is now a shift from the question “whose DNA is this?” to the question “how did it get there?” As a consequence, recipients of expert information are now very much in need of assistance with the evaluation of the meaning and probative strength of DNA profiling results when the competing propositions of interest refer to different activities. This need is widely demonstrated in day-to-day forensic practice and is also voiced in specialized literature. Yet many forensic scientists remain reluctant to assess their results given propositions that relate to different activities. Some scientists consider evaluations beyond the issue of source as being overly speculative, because of the lack of relevant data and knowledge regarding phenomena and mechanisms of transfer, persistence and background of DNA. Similarly, encouragements to deal with these activity issues, expressed in a recently released European guideline on evaluative reporting (Willis et al., 2015), which highlights the need for rethinking current practice, are sometimes viewed skeptically or are not considered feasible. In this discussion paper, we select and discuss

  11. Determination of several trace elements in Chinese herbs with epithermal neutral activation analysis

    Chen, Chien-Yi [Chung Shan Medical Univ., Inst. of Biochemistry, Taiwan (China); Chang Lai, Sheng-Pin [Chung Shan Medical Univ. Hospital, Dept. of Nuclear Medicine Chief, Taiwan (China)

    2002-04-01

    For purpose of medication and health, Chinese herbs have been long adopted throughout oriental communities. Thus, more than ten trace elements in herbal medicines that are frequently consumed by children in central Taiwan were analyzed herein to explore the importance of various herbs. These elements are considered beneficial to human health in many folds. INAA was applied to determine the concentrations of elements as Al, Cl and Sc, while ENAA analyzed As, Cd, Mn, and Sb in this work. Among various local herbs, the elemental concentrations varied from 10{sup 4} to 10{sup -3} {mu}g/g. The experimental results suggest that the ENAA method can be applied successfully to analyze trace elements of As, Cd, Mn, and Sb in herbs. Yet, thirteen elements were verified, and a quantified index AT was introduced to help classifying the elements. The ATs in various Chinese herbs are also discussed herein and the accuracy is in excellent agreement with values reported in previously published data. (author)

  12. Measurement of gas/water uptake coefficients for trace gases active in the marine environment

    Davidovits, P. (Boston Coll., Chestnut Hill, MA (United States). Dept. of Chemistry); Worsnop, D.W.; Zahniser, M.S.; Kolb, C.E. (Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics)

    1992-02-01

    Ocean produced reduced sulfur compounds including dimethylsulfide (DMS), hydrogen sulfide (H{sub 2}S), carbon disulfide (CS{sub 2}), methyl mercaptan (CH{sub 3}CH) and carbonyl sulfide (OCS) deliver a sulfur burden to the atmosphere which is roughly equal to sulfur oxides produced by fossil fuel combustion. These species and their oxidation products dimethyl sulfoxide (DMSO), dimethyl sulfone (DMSO{sub 2}) and methane sulfonic acid (MSA) dominate aerosol and CCN production in clean marine air. Furthermore, oxidation of reduced sulfur species will be strongly influenced by NO{sub x}/O{sub 3} chemistry in marine atmospheres. The multiphase chemical processes for these species must be understood in order to study the evolving role of combustion produced sulfur oxides over the oceans. We have measured the chemical and physical parameters affecting the uptake of reduced sulfur compounds, their oxidation products, ozone, and nitrogen oxides by the ocean's surface, and marine clouds, fogs, and aerosols. These parameters include: gas/surface mass accommodation coefficients; physical and chemically modified (effective) Henry's law constants; and surface and liquid phase reaction constants. These parameters are critical to understanding both the interaction of gaseous trace species with cloud and fog droplets and the deposition of trace gaseous species to dew covered, fresh water and marine surfaces.

  13. Monolithic active pixel radiation detector with shielding techniques

    Deptuch, Grzegorz W.

    2018-03-20

    A monolithic active pixel radiation detector including a method of fabricating thereof. The disclosed radiation detector can include a substrate comprising a silicon layer upon which electronics are configured. A plurality of channels can be formed on the silicon layer, wherein the plurality of channels are connected to sources of signals located in a bulk part of the substrate, and wherein the signals flow through electrically conducting vias established in an isolation oxide on the substrate. One or more nested wells can be configured from the substrate, wherein the nested wells assist in collecting charge carriers released in interaction with radiation and wherein the nested wells further separate the electronics from the sensing portion of the detector substrate. The detector can also be configured according to a thick SOA method of fabrication.

  14. Accelerated line-by-line calculations for the radiative transfer of trace gases related to climate studies

    Clough, S.A.

    1993-01-01

    In the present study we are studying the effects of including carbon dioxide, ozone, methane, and the halocarbons in addition to water vapor in the radiating atmosphere. The study has focused on two principal issues: the effect on the spectral fluxes and cooling rates of carbon dioxide, ozone and the halocarbons at 1990 concentration levels and the change in fluxes and cooling rates as a consequence of the anticipated ten year change in the profiles of these species. For the latter study the water vapor profiles have been taken as invariant in time. The radiative line-by-line calculations using LBLRTM (Line-By-Line Radiative Transfer Model) have been performed for tropical (TRP), mid-latitude winter (MLW) and mid-latitude summer (MLS) model atmospheres. The halocarbons considered in the present study are CCl 4 , CFC-11, CFC-12 and CFC-22. In addition to considering the radiative effects of carbon dioxide at 355 ppM, the assumed current level, we have also obtained results for doubled carbon dioxide at 710 ppM. An important focus of the current research effort is the effect of the ozone depletion profile on atmospheric radiative effects

  15. Metal and trace element assessment of estuary sediments from Santos, Brazil, by neutron activation and atomic absorption techniques

    Amorim, Eduardo P.; Favaro, Deborah I.T.; Berbel, Glaucia B.B.; Braga, Elisabete S.

    2007-01-01

    In order to better understanding geochemical and environmental processes and their possible changes due to anthropogenic activities trace metal analyses and their distribution in marine sediments are commonly undertaken. The present study reports result concerning the distribution of some major, trace and rare earth elements in the Santos estuarine marine sediments. Thirteen bottom sediment samples (SV0501 to SV0513) were collected in this estuary, including regions of Sao Vicente, Santos, Cubatao, Vicente de Carvalho and Santos' Bay, in the summer of 2005. Multielemental analysis was carried out by instrumental neutron activation analysis (INAA). For total mercury determination cold vapor atomic absorption technique (CV AAS) was employed. In both cases methodology validation was performed by certified reference material analyses. The results obtained for multielemental concentrations in the sediment samples were compared with NASC (North American Shale Composite) values. The concentration values obtained for As and metals Cr, Hg and Zn in the sediment samples were compared to Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL values). In general, the samples located near the Cubatao region showed higher concentrations for all elements analyzed probably due to the high impact of industrial activities. (author)

  16. Metal and trace element assessment of estuary sediments from Santos, Brazil, by neutron activation and atomic absorption techniques

    Amorim, Eduardo P.; Favaro, Deborah I.T. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mails: ducamorim@yahoo.com.br; defavaro@ipen.br; Berbel, Glaucia B.B.; Braga, Elisabete S. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. Oceanografico. Lab. de Nutrientes, Micronutrientes e Tracos nos Oceanos - LABNUT]. E-mail: edsbraga@usp.br

    2007-07-01

    In order to better understanding geochemical and environmental processes and their possible changes due to anthropogenic activities trace metal analyses and their distribution in marine sediments are commonly undertaken. The present study reports result concerning the distribution of some major, trace and rare earth elements in the Santos estuarine marine sediments. Thirteen bottom sediment samples (SV0501 to SV0513) were collected in this estuary, including regions of Sao Vicente, Santos, Cubatao, Vicente de Carvalho and Santos' Bay, in the summer of 2005. Multielemental analysis was carried out by instrumental neutron activation analysis (INAA). For total mercury determination cold vapor atomic absorption technique (CV AAS) was employed. In both cases methodology validation was performed by certified reference material analyses. The results obtained for multielemental concentrations in the sediment samples were compared with NASC (North American Shale Composite) values. The concentration values obtained for As and metals Cr, Hg and Zn in the sediment samples were compared to Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL values). In general, the samples located near the Cubatao region showed higher concentrations for all elements analyzed probably due to the high impact of industrial activities. (author)

  17. International Activities in Radiation-Induced Carcinogenesis. Survey Paper

    Komarov, E. [World Health Organization, Geneva (Switzerland)

    1969-11-15

    During the past 10 years special attention has been paid to the problem of late effects of radiation and in particular to radiation-induced carcinogenesis and leukaemogenesis. In the UNSCEAR report of 1958-1962 this.problem was mentioned as being of considerable importance from the point of view of estimation of risk to the population from environmental radiation. In 1964 a special report was prepared by UNSCEAR on radiation- induced carcinogenesis. In the ICRP publication No. 8, a chapter dealing with assessment of somatic risks discussed the problem of leukaemia and other neoplasms and particularly stressed the problem of thyroid carcinoma-and bone sarcoma. WHO panels of experts discussed the problem in 1960-1966 and made some recommendations for international activity in this field. In spite of the amount of scientific attention that has been given in recent years to experimental radiobiology in animals and lower forms, it has become abundantly clear that information directly applicable to humans is woefully inadequate and that there is a desperate need for carefully collected data from man on which to base public health planning and day to day work in radiation protection. This has long been recognized in the technical program of WHO in the emphasis given to the practical importance of epidemiology in human radiobiology and the degree to which it depends upon international collaboration.

  18. Two-dimensional micro-beam imaging of trace elements in a single plankton measured by a synchrotron radiation X-ray fluorescence analysis

    Ezoe, Masako; Sasaki, Miho; Hokura, Akiko; Nakai, Izumi; Terada, Yasuko; Yoshinaga, Tatsuki; Tukamoto, Katsumi; Hagiwara, Atsushi

    2002-01-01

    Two-dimensional imaging and a quantitative analysis of trace elements in rotifer, Brachionus plicatilis, belonging to zooplankton, were carried out by a synchrotron radiation X-ray fluorescence analysis (SR-XRF). The XRF imaging revealed that female rotifers accumulated Fe and Zn in the digestive organ and Fe, Zn, Cu, and Ca in the sexual organs, while the Mn level was high in the head. From a quantitative analysis by inductively coupled plasma mass spectrometry (ICP-MS), we found that rotifers eat the chlorella and accumulate the above elements in the body. The result of quantitative analyses of Mn, Cu, and Zn by SR-XRF in a single sample is in fair agreement with the average values determined by ICP-MS analyses, which were obtained by measuring a large number of rotifers, digested by nitric acid. The present study has demonstrated that SR-XRF is an effective tool for the trace element analysis of a single individual of rotifer. (author)

  19. Two-dimensional micro-beam imaging of trace elements in a single plankton measured by a synchrotron radiation X-ray fluorescence analysis

    Ezoe, Masako; Sasaki, Miho; Hokura, Akiko; Nakai, Izumi [Tokyo Univ. of Science, Faculty of Science, Tokyo (Japan); Terada, Yasuko [Japan Synchrotron Radiation Research Inst., Mikazuki, Hyogo (Japan); Yoshinaga, Tatsuki; Tukamoto, Katsumi [Tokyo Univ., Ocean Research Inst., Tokyo (Japan); Hagiwara, Atsushi [Nagasaki Univ., Graduate School of Science and Technology, Bunkyou, Nagasaki (Japan)

    2002-10-01

    Two-dimensional imaging and a quantitative analysis of trace elements in rotifer, Brachionus plicatilis, belonging to zooplankton, were carried out by a synchrotron radiation X-ray fluorescence analysis (SR-XRF). The XRF imaging revealed that female rotifers accumulated Fe and Zn in the digestive organ and Fe, Zn, Cu, and Ca in the sexual organs, while the Mn level was high in the head. From a quantitative analysis by inductively coupled plasma mass spectrometry (ICP-MS), we found that rotifers eat the chlorella and accumulate the above elements in the body. The result of quantitative analyses of Mn, Cu, and Zn by SR-XRF in a single sample is in fair agreement with the average values determined by ICP-MS analyses, which were obtained by measuring a large number of rotifers, digested by nitric acid. The present study has demonstrated that SR-XRF is an effective tool for the trace element analysis of a single individual of rotifer. (author)

  20. Neutron activation analysis in forensic investigations. Trace elements characterization of cigarettes

    Giordani, L.; Rizzio, E.; Brandone, A.

    2005-01-01

    Police investigations of the Italian Ministry of Treasury Police involving the illicit sale of tobacco lead to the confiscation of large quantities of smuggled cigarettes. Thousands of tons of cigarettes of different manufacturers are sequestrated yearly in many regions of Italy and different criminal organizations have been identified as unlawful importers. In order to verify whether the recovered smuggled lots of cigarettes come from the official manufacturers, or they have produced illicitly, usually chemical analysis are carried out. By the determination of trace elements content, specific information can be obtained by comparing different brands of cigarettes and different batches of tobacco. Samples of tobacco of cigarettes manufactured by the Italian State Monopoly, taken as 'reference samples', have been compared with those of illicit origin. Elements such as Co, Br, Cr and Sc have been found to be useful for the selective characterization. The results, submitted to statistical elaboration, provided important information on the origin of smuggled cigarettes. (author)

  1. Activation analytical determination of essential and toxic trace elements in biological material

    Schelenz, R.

    1980-01-01

    In order to determine the essential trace elements Hg, Ag, Cu and Se in food (potatoes, milk powder) and biological standard materials (fruit tree leaves), simple, fast radiochemical separation methods are worked out. Following oxidative decomposition and destillation of Hg, the elements silver, copper and selenium are found in the destillation residue and can be electrochemically enriched on an amalgamated Cu foil (determination of Ag and Se in the concentration range of 10 -9 to 10 -8 g, of Cu in the range of 10 -12 to 10 -10 g), whilst the matrix elements Na, K, P are adsorbed on a column with 3 different inorganic ion exchangers. The eluate of the ion exchanger can be added directly to the multielement gamma spectroscopy. The possiblity of working purely instrumentally is demonstrated by 2 examples: multielement analysis of human hair and river water. (RB) [de

  2. Utilization of Neutron Activation Analysis for geochemical study of major and trace elements in Bouregreg river basin (Morocco)

    Bounouira, H.; Bounakhla, M.; Embarch, K.; Choukri, A.; Cherkaoui, R.; Gaudry, A.; Treuil, M.; Chakiri, S.

    2010-01-01

    The Bouregreg river basin is located in the moroccan central massif which consists mainly of palaeozoic formations that were subject to the Hercynian orogeny. This study documents the backround geochemistry and hydrochemistry of the Bouregreg river basin, focusing on the distribution of major and trace elements, Rock samples were collected at 9 locations along the bouregreg river and its tributaries in the winter of 2005. Major (Al, fe, Mn, Na, K and Ti) and trace (Rb, Cs, Sr, Sc, Ba, Cr, V, Co, Ni, Zn, As, Sb, La, Ce, Nd, Sm, Tb, Dy, Yb, Lu, Hf, Ta, Mo, Th and U) elements were anlysed using instrumental Neutron Activation Analysis (INAA). Data show that most of the geochemistry and hydrochemistry are related to regional and local geology. the geochemical heritage of geological environment in the Bouregreg river basin is very important, that results from the more compatible behaviour and the inertia of some elements during the weathering (3d transition elements (Co, Ni, Cr,...), interne transition elements f (lanthanides, Zr, Hf, Nb, Ta,...)). The geochemical homogeneity of the basin shows also heritage during the crustal accretion (magmatism-metamorphism-sedimention) and the typology of this continental area is the same that the Upper Continental Crust (UCC). Some anomalously high heavy metal analyses, particulary for As and Sb, may be related to anthropogenic activities

  3. Trace elements in several species of crustaceans of Amami Island Group in Japan determined by activation analysis

    Fukushima, M.; Tamate, H.; Nakano, Y.

    2001-01-01

    Concentration levels of trace elements were determined in several species of subtropical crustaceans from Amami Islands in Japan in order to evaluate the levels of specific accumulation of elements among species. Tissue samples prepared from gill, muscle, hepatopancreas, and testis were irradiated for photon activation analysis (PAA) and neutron activation analysis (NAA). By PAA and NAA, eighteen elements could be determined. The levels of Br and I were extremely high in gills of spiny lobster and shovel-nosed lobster, respectively. A high concentration of Ag was found in the hepatopancreas of spiny lobsters collected from the Amami Island, while this element was not detected in the same species collected from Toba. The results suggest that the distribution of the trace elements in different tissues and species varies according to both species and environmental differences. To study the molecular forms of the elements in tissue, fractions that contained protein-bound elements from the hepatopancreas of spiny lobsters were separated by ultracentrifugation and gel filtration chromatography. Elution profiles of the chromatography suggest that Cu, Fe, and Se were bound to proteins, while Ag was not. (author)

  4. Metal and trace element assessment of sediments from Guarapiranga reservoir, Sao Paulo State, by neutron activation analysis

    Guimaraes, Guilherme M.; Favaro, Deborah I.T.; Franklin, Robson L.; Ferreira, Francisco J.; Bevilacqua, Jose E.

    2009-01-01

    Guarapiranga Reservoir is extremely important due to the fact that it is one of the main water reservoirs for South America's largest city, Sao Paulo, Brazil. Guarapiranga Basin is located within the Metropolitan Region of Sao Paulo - RMSP, and occupies an area of approximately 630 km 2 , and the reservoir itself is located in the northern part of the basin occupying approximately 26 km 2 . This reservoir is characterized by environmental impacts from urban invasion, industrial and sewage wastes, all of which seriously affect its water quality. Due to its vulnerability CETESB (Environmental Control Agency of the Sao Paulo State) regularly monitors the contamination levels of waters and once a year sediment samples. In order to better understand geochemical and environmental processes and their possible changes due to anthropogenic activities trace metals analyses and their distribution in sediments are commonly undertaken. The present study reports results concerning the distribution of some major (Fe, K and Na), trace (As, Ba, Br, Co, Cr, Cs, Hf, Hg, Rb, Sb, Sc, Ta, Tb, Th, U and Zn) and rare earth (Ce, Eu, La, Lu, Nd, Sm, Tb and Yb) elements in sediments from the Guarapiranga Reservoir. Multielementar analysis was carried out by instrumental neutron activation analysis (INAA). Multielemental concentrations in the sediment samples were compared to NASC (North American Shale Composite) values. The concentration values for metals As, Cr and Zn in the sediment samples were compared to the Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL values) and adopted by CETESB. (author)

  5. A theoretical approach to photosynthetically active radiation silicon sensor

    Tamasi, M.J.L.; Martínez Bogado, M.G.

    2013-01-01

    This paper presents a theoretical approach for the development of low cost radiometers to measure photosynthetically active radiation (PAR). Two alternatives are considered: a) glass optical filters attached to a silicon sensor, and b) dielectric coating on a silicon sensor. The devices proposed are based on radiometers previously developed by the Argentine National Atomic Energy Commission. The objective of this work is to adapt these low cost radiometers to construct reliable instruments for measuring PAR. The transmittance of optical filters and sensor response have been analyzed for different dielectric materials, number of layers deposited, and incidence angles. Uncertainties in thickness of layer deposition were evaluated. - Highlights: • Design of radiometers to measure photosynthetically active radiation • The study has used a filter and a Si sensor to modify spectral response. • Dielectric multilayers on glass and silicon sensor • Spectral response related to different incidence angles, materials and spectra

  6. An activated sludge modeling framework for xenobiotic trace chemicals (ASM-X): assessment of diclofenac and carbamazepine.

    Plósz, Benedek Gy; Langford, Katherine H; Thomas, Kevin V

    2012-11-01

    Conventional models for predicting the fate of xenobiotic organic trace chemicals, identified, and calibrated using data obtained in batch experiments spiked with reference substances, can be limited in predicting xenobiotic removal in wastewater treatment plants (WWTPs). At stake is the level of model complexity required to adequately describe a general theory of xenobiotic removal in WWTPs. In this article, we assess the factors that influence the removal of diclofenac and carbamazepine in activated sludge, and evaluate the complexity required for the model to effectively predict their removal. The results are generalized to previously published cases. Batch experimental results, obtained under anoxic and aerobic conditions, were used to identify extensions to, and to estimate parameter values of the activated sludge modeling framework for Xenobiotic trace chemicals (ASM-X). Measurement and simulation results obtained in the batch experiments, spiked with the diclofenac and carbamazepine content of preclarified municipal wastewater shows comparably high biotransformation rates in the presence of growth substrates. Forward dynamic simulations were performed using full-scale data obtained from Bekkelaget WWTP (Oslo, Norway) to evaluate the model and to estimate the level of re-transformable xenobiotics present in the influent. The results obtained in this study demonstrate that xenobiotic loading conditions can significantly influence the removal capacity of WWTPs. We show that the trace chemical retransformation in upstream sewer pipes can introduce considerable error in assessing the removal efficiency of a WWTP, based only on parent compound concentration measurements. The combination of our data with those from the literature shows that solids retention time (SRT) can enhance the biotransformation of diclofenac, which was not the case for carbamazepine. Model approximation of the xenobiotic concentration, detected in the solid phase, suggest that between

  7. Radiation safety in radioluminous paint workshop handling tritium activated paint

    Gaur, P.K.; Venkateswaran, T.V.

    1986-01-01

    This paper discusses the safety features related to a workshop when tritium activated luminous paint is handled by workmen. Salient features of the workshop and the methods employed for monitoring the radiation levels are briefly outlined and results are discussed. The importance of proper ventilation of the workplace and precautions to be taken in the storage of painted articles are highlighted. (author). 1 table, 3 figs

  8. New radiative transfer models for obscuring tori in active galaxies

    van Bemmel, I. M.; Dullemond, C. P.

    2003-01-01

    Two-dimensional radiative transfer is employed to obtain the broad-band infrared spectrum of active galaxies. In the models we vary the geometry and size of the obscuring medium, the surface density, the opacity and the grain size distribution. Resulting spectral energy distributions are constructed for different orientations of the toroid. Colour-colour comparisons with observational data are consistent with previous observations that the emission longward of 60 micron is produced by star-fo...

  9. Radiation hygiene analysis of medical activities in Norway

    Olerud, H.M.

    1987-01-01

    A computer program for the evaluation of radiation protection parameters connected to diagnostic X-ray examination has been developed. For a selected X-ray examination the program picks out key values from a data base containg patient observations and calculates integral doses, collective doses and i njury cases . When the volume of the data base is sufficient large, a total concequence analysis of diagnostric X-ray activities in Norway will be carried out

  10. Nuclear traces in glass

    Segovia A, M. de N.

    1978-01-01

    The charged particles produce, in dielectric materials, physical and chemical effects which make evident the damaged zone along the trajectory of the particle. This damaged zone is known as the latent trace. The latent traces can be enlarged by an etching of the detector material. This treatment attacks preferently the zones of the material where the charged particles have penetrated, producing concavities which can be observed through a low magnification optical microscope. These concavities are known as developed traces. In this work we describe the glass characteristics as a detector of the fission fragments traces. In the first chapter we present a summary of the existing basic theories to explain the formation of traces in solids. In the second chapter we describe the etching method used for the traces development. In the following chapters we determine some chatacteristics of the traces formed on the glass, such as: the development optimum time; the diameter variation of the traces and their density according to the temperature variation of the detector; the glass response to a radiation more penetrating than that of the fission fragments; the distribution of the developed traces and the existing relation between this ditribution and the fission fragments of 252 Cf energies. The method which has been used is simple and cheap and can be utilized in laboratories whose resources are limited. The commercial glass which has been employed allows the registration of the fission fragments and subsequently the realization of experiments which involve the counting of the traces as well as the identification of particles. (author)

  11. Evaluation of some procedures relevant to the determination of trace elemental components in biological materials by destructive neutron activation analysis

    Berry, D.L.

    1979-01-01

    The development of a simplified procedure for the analysis of biological materials by destructive neutron activation analysis (DNAA) is described. The sample manipulations preceding gamma ray assay were investigated as five specific stages of processing: (1) pre-irradiation treatment; (2) sample irradiation; (3) removal of the organic matrix; (4) removal of interfering radioactivities; and (5) concentration and separation of analyte activities. Each stage was evaluated with respect to susceptibility to sample contamination, loss of trace elemental components, and compatibility with other operations in the overall DNAA procedures. A complete DNAA procedure was proposed and evaluated for the analysis of standard bovine liver and blood samples. The DNAA system was effective for the determination of As, Cu, Fe, Hg, Mo, Rb, Sb, Se, and Zn without yield determinations and with a minimum turn-around time of approximately 3 days

  12. Evaluation of some procedures relevant to the determination of trace elemental components in biological materials by destructive neutron activation analysis

    Berry, D.L.

    1979-01-01

    The development of a simplified procedure for the analysis of biological materials by destructive neutron activation analysis (DNAA) is described. The sample manipulations preceding gamma ray assay were investigated as five specific stages of processing: (1) pre-irradiation treatment; (2) sample irradiation; (3) removal of the organic matrix; (4) removal of interfering radioactivities; and (5) concentration and separation of analyte activities. Each stage was evaluated with respect to susceptibility to sample contamination, loss of trace elemental components, and compatibility with other operations in the overall DNAA procedures. A complete DNAA procedure was proposed and evaluated for the analysis of standard bovine liver and blood samples. The DNAA system was effective for the determination of As, Cu, Fe, Hg, Mo, Rb, Sb, Se, and Zn without yield determinations and with a minimum turn-around time of approximately 3 days.

  13. Neutron activation analysis and the geochemistry of common and trace elements at extinction boundaries in the geological record

    Attrep, M. Jr.; Orth, C.J.; Quintana, L.R.

    1994-01-01

    The discovery of the iridium anomaly at the 65-Ma Cretaceous-Tertiary (K-T) extinction boundary initiated numerous investigations, including the search for the coupling of these extinctions with other astronomical events. One hypothesis is that these periodic extinctions are coupled to terrestrial impacts from cyclic swarms of comets or asteroids. The studies have focused on elucidating the conditions and causes of extinction of life at these geological boundaries using elemental abundance patterns. The authors use instrumental neutron activation methods to determine whole-rock abundances for about 40 trace and common elements in thousands of samples. The platinum group elements (iridium, gold, platinum, and osmium) and nickel are measured by radiochemical activation analysis. The authors can measure iridium at levels down to 1 picogram/gram level

  14. Determination of trace elements in eyeshadow, face powder and rouge make-up cosmetics by neutron activation analysis

    Kanias, G.D.

    1985-01-01

    Some trace elements exist in cosmetics due to the mineral origin of their raw materials and there is no information about their concentration levels in these products. Instrumental neutron activation analysis was applied to determine the elements: cerium, cesium, europium, hafnium, lanthanum, lutetium, potassium, rubidium, samarium, scandium, sodium, tantalum, terbium, tungsten and ytterbium in eyeshadow, face powder and rouge make-up cosmetic products from the Greek market. According to the results, a wide range of values was found between the three examined cosmetics as well as between the different samples belonging to the same kind of cosmetics. This probably could be attributed to the various manufacturers of the analyzed samples. Moreover, the use of neutron activation analysis as a suitable routine method is discussed for the control of some elements which must not be contained in cosmetics. (author)

  15. Neutron activation analysis for environmental trace element research determination of elemental composition of sediments in the Sea of Galillee, Israel

    Lavi, N; Ne` eman, E; Brenner, S; Butenko, V [Tel Aviv Univ. (Israel). Medical School

    1996-12-01

    The aims of this work were to: a) demonstrate the effectiveness of instrumental neutron activation analysis for determining the background concentrations of trace elements in the sediments collected from the Sea of Gallile. b) determine the advantage factors for epithermal neutron irradiation. c) determine the contribution of silicon to the total {sup 28}Al activity by the {sup 28}Si(n,p){sup 28}Al reaction. c) check the validity of the method by determining the elemental content of U.S. NBS Standard Reference Material SRM-1633a (fly ash). d) calculate the average enrichment factors for the elements in sediments . e) determine the concentrations of the artificial radionuclides {sup 134}Cs, {sup 137}Cs and the naturally occurring radionuclides {sup 40}K, {sup 226}Ra and {sup 232}Th (authors).

  16. Trace element content of human hair determined using neutron activation analysis as monitor of exposure effects to environmental metals

    Dutkiewicz, T.; Paprotny, W.; Sokolowska, D.; Kulka, E.; Woyciechowska, E.; Dybczynski, R.; Sterlinski, S.

    1978-01-01

    Determination of 17 trace elements, mainly metals, in small hair samples by neutron activation analysis was elaborated. The number of elements determined in one sample made it possible to assess quickly the exposure of human population in a given region. The hair samples after careful washing according to procedure elaborated previously were irradiated in high reactor neutron flux (approximately 10 14 n.cm -2 .s -1 ). The activities of samples were measured three times (for different decay times) by means of Ge(Li) gamma-ray spectrometer. A new version of the comparator technique, called a triple-single comparator method, was applied for quantitative analysis. The statistical methods used for planning of sampling and preliminary results on evaluation of analytical data are also described. (author)

  17. Assessment of the accuracy of the conventional ray-tracing technique: Implications in remote sensing and radiative transfer involving ice clouds

    Bi, Lei; Yang, Ping; Liu, Chao; Yi, Bingqi; Baum, Bryan A.; Diedenhoven, Bastiaan van; Iwabuchi, Hironobu

    2014-01-01

    A fundamental problem in remote sensing and radiative transfer simulations involving ice clouds is the ability to compute accurate optical properties for individual ice particles. While relatively simple and intuitively appealing, the conventional geometric-optics method (CGOM) is used frequently for the solution of light scattering by ice crystals. Due to the approximations in the ray-tracing technique, the CGOM accuracy is not well quantified. The result is that the uncertainties are introduced that can impact many applications. Improvements in the Invariant Imbedding T-matrix method (II-TM) and the Improved Geometric-Optics Method (IGOM) provide a mechanism to assess the aforementioned uncertainties. The results computed by the II-TM+IGOM are considered as a benchmark because the II-TM solves Maxwell's equations from first principles and is applicable to particle size parameters ranging into the domain at which the IGOM has reasonable accuracy. To assess the uncertainties with the CGOM in remote sensing and radiative transfer simulations, two independent optical property datasets of hexagonal columns are developed for sensitivity studies by using the CGOM and the II-TM+IGOM, respectively. Ice cloud bulk optical properties obtained from the two datasets are compared and subsequently applied to retrieve the optical thickness and effective diameter from Moderate Resolution Imaging Spectroradiometer (MODIS) measurements. Additionally, the bulk optical properties are tested in broadband radiative transfer (RT) simulations using the general circulation model (GCM) version of the Rapid Radiative Transfer Model (RRTMG) that is adopted in the National Center for Atmospheric Research (NCAR) Community Atmosphere Model (CAM, version 5.1). For MODIS retrievals, the mean bias of uncertainties of applying the CGOM in shortwave bands (0.86 and 2.13 μm) can be up to 5% in the optical thickness and as high as 20% in the effective diameter, depending on cloud optical

  18. Microbial community structure and activity in trace element-contaminated soils phytomanaged by Gentle Remediation Options (GRO).

    Touceda-González, M; Prieto-Fernández, Á; Renella, G; Giagnoni, L; Sessitsch, A; Brader, G; Kumpiene, J; Dimitriou, I; Eriksson, J; Friesl-Hanl, W; Galazka, R; Janssen, J; Mench, M; Müller, I; Neu, S; Puschenreiter, M; Siebielec, G; Vangronsveld, J; Kidd, P S

    2017-12-01

    Gentle remediation options (GRO) are based on the combined use of plants, associated microorganisms and soil amendments, which can potentially restore soil functions and quality. We studied the effects of three GRO (aided-phytostabilisation, in situ stabilisation and phytoexclusion, and aided-phytoextraction) on the soil microbial biomass and respiration, the activities of hydrolase enzymes involved in the biogeochemical cycles of C, N, P, and S, and bacterial community structure of trace element contaminated soils (TECS) from six field trials across Europe. Community structure was studied using denaturing gradient gel electrophoresis (DGGE) fingerprinting of Bacteria, α- and β-Proteobacteria, Actinobacteria and Streptomycetaceae, and sequencing of DGGE bands characteristic of specific treatments. The number of copies of genes involved in ammonia oxidation and denitrification were determined by qPCR. Phytomanagement increased soil microbial biomass at three sites and respiration at the Biogeco site (France). Enzyme activities were consistently higher in treated soils compared to untreated soils at the Biogeco site. At this site, microbial biomass increased from 696 to 2352 mg ATP kg -1 soil, respiration increased from 7.4 to 40.1 mg C-CO 2 kg -1 soil d -1 , and enzyme activities were 2-11-fold higher in treated soils compared to untreated soil. Phytomanagement induced shifts in the bacterial community structure at both, the total community and functional group levels, and generally increased the number of copies of genes involved in the N cycle (nirK, nirS, nosZ, and amoA). The influence of the main soil physico-chemical properties and trace element availability were assessed and eventual site-specific effects elucidated. Overall, our results demonstrate that phytomanagement of TECS influences soil biological activity in the long term. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Gamma radiation treatment activates glucomoringin synthesis in Moringa oleifera

    Tsifhiwa Ramabulana

    Full Text Available Abstract Plants are a very rich source of pharmacologically relevant metabolites. However, the relative concentrations of these compounds are subject to the genetic make-up, the physiological state of the plant as well as environmental effects. Recently, metabolic perturbations through the use of abiotic stressors have proven to be a valuable strategy for increasing the levels of these compounds. Oxidative stress-associated stressors, including ionizing radiation, have also been reported to induce metabolites with various biological activities in plants. Hence, the aim of the current study was to investigate the effect of gamma radiation on the induction of purported anti-cancerous metabolites, glucomoringin and its derivatives, in Moringa oleifera Lam., Moringaceae. Here, an UHPLC-qTOF-MS-based targeted metabolic fingerprinting approach was used to evaluate the effect of gamma radiation treatment on the afore-mentioned health-beneficial secondary metabolites of M. oleifera. Following radiation, an increase in glucomoringin and three acylated derivatives was noted. As such, these molecules can be regarded as components of the inducible defense mechanism of M. oleifera as opposed to being constitutive components as it has previously been assumed. This might be an indication of a possible, yet unexplored role of moringin against the effects of oxidative stress in M. oleifera plants. The results also suggest that plants undergoing photo-oxidative stress could accumulate higher amounts of glucomoringin and related molecules.

  20. Active Radiative Thermal Switching with Graphene Plasmon Resonators.

    Ilic, Ognjen; Thomas, Nathan H; Christensen, Thomas; Sherrott, Michelle C; Soljačić, Marin; Minnich, Austin J; Miller, Owen D; Atwater, Harry A

    2018-03-27

    We theoretically demonstrate a near-field radiative thermal switch based on thermally excited surface plasmons in graphene resonators. The high tunability of graphene enables substantial modulation of near-field radiative heat transfer, which, when combined with the use of resonant structures, overcomes the intrinsically broadband nature of thermal radiation. In canonical geometries, we use nonlinear optimization to show that stacked graphene sheets offer improved heat conductance contrast between "ON" and "OFF" switching states and that a >10× higher modulation is achieved between isolated graphene resonators than for parallel graphene sheets. In all cases, we find that carrier mobility is a crucial parameter for the performance of a radiative thermal switch. Furthermore, we derive shape-agnostic analytical approximations for the resonant heat transfer that provide general scaling laws and allow for direct comparison between different resonator geometries dominated by a single mode. The presented scheme is relevant for active thermal management and energy harvesting as well as probing excited-state dynamics at the nanoscale.

  1. Activities of Protection against Ionizing Radiation in Niger

    Kando Hamadou, M.

    2008-01-01

    Niger, sahelian country of Western Africa, is limited to North by Libya and Algeria, to the South by Nigeria and the Benin, to the East by Chad and the West by Mali and Burkina Faso. It covers a surface of 1 267 000 km2 and has a population of approximately 12 000 000 inhabitants. Niger is a large uranium producer with two extraction and treatment development companies of uranium ore which are the company of the mines of Air (SOMAIR) created in 1971 and the mining company of Akouta (COMINAK) created in 1978. Beyond the mining sector, ionizing radiation sources are used in the fields of industry, health, teaching and research. The first lawful text of protection against ionizing radiation was signed on December 5, 1979 and specifically related to the mining activities of uranium. With the multiform assistance of International Atomic Energy Agency (IAEA) protection against radiation knew a significant evolution. A national centre of protection against radiation was created in 1998, two laws relating to the field were adopted in June 2006 and three lawful texts of application of these laws are in the process of finalization

  2. Sequential activation of proteases in radiation induced apoptosis

    Watters, D.; Waterhouse, N.

    1997-01-01

    Full text: Significant advances have been made in recent years in unraveling the molecular mechanisms of apoptosis particularly in relation to Fas- and TNF-mediated cell death, however there are considerable gaps in our knowledge of the processes involved in apoptosis induced by ionizing radiation. We have used the degradation of specific proteolytic targets in a pair of isogenic Burkitt's Iymphoma cells lines (BL30A, sensitive and BL30K resistant) to study the sequence of events in the execution of radiation-induced apoptosis. Fodrin can be cleaved to fragments of 150 kDa and 120 kDa. In the case of Fas-mediated apoptosis both cleavages are inhibited by the caspase inhibitor zVAD-fmk at 10 μM, a concentration which inhibits all the hallmarks of apoptosis. However in radiation-induced apoptosis, inhibition of the clevage of fodrin to the 150 kDa fragment requires 100 μM zVAD-fink while apoptosis itself is inhibited at 10 μM. This suggests that different enzymes are responsible for the generation of the 150 kDa fragment in the two models of apoptosis. Fodrin has been reported to be cleaved by μ-calpain to a 150 kDa fragment however, the involvement of μ-calpain in apoptosis has not yet been established. In murine fodrin there is a caspase cleavage site within 1 kDa of the calpain cleavage site. In vitro studies using purified enzymes showed that only caspase-3 and μ-calpain could cleave fodrin in untreated cell extracts to the same sized fragments as seen during apoptosis in vivo. We provide evidence for the early activation of μ-calpain after ionizing radiation in the sensitive BL30A cell line, and show that the time course of μ-calpain activation parallels that of the appearance of the 150 kDa fragment. Caspase-3 is activated much later and is likely to be responsible for the generation of the 120 kDa fragment. μ-Calpain was not activated in the resistant cell line. Based on these results we propose a model for the proteolytic cascade in radiation

  3. Comparison of leaves of Nerium oleander collected the monitoring trace elements in environmental pollution in Rio de Janeiro and Campinas Cities using of synchrotron radiation fluorescence analysis

    Simabuco, Silvana M.; Ferreira Pinto, Jefferson; Dos Anjos, Marcelino J.

    1999-01-01

    These works describes the use of synchrotron radiation fluorescence analysis as a technique for monitoring trace elements in bio-indicators for environmental pollution control. The analyses were made on leaves of Nerium oleander collected in streets with different traffic flow in Rio de Janeiro and Campinas Cities, Brazil, with one sample from rural zone. Part of the leaves were cleaned with 0,1% v/v detergent in deionized water and than all were dry at 60o C until constant weight. The leaves were than cut in small pieces and submitted to a nitric digestion in a open system. The liquid residue was pre-concentrated with ammonium pirrrolidine dithiocarbamate and filtrated by vacuum pump in cellulose membrane. The measurement was made with a white beam of synchrotron radiation calibrated with thin film standards. The results indicate that same metals like Ti, V, Fe and Zn have major content in sample that came from places with high traffic flow even in leaves that have been washed. The levels of Mn, Co, Cu and Ni did not show significant difference between the samples. The Pb level also did not vary significantly what was expected because in Brazil the gasoline did not use plumb as a additive from many years. The results seems to indicate that the leaves from Nerium oleander absorb metals from the atmosphere and may be used as one environmental indicator

  4. Radiation degradation of carbohydrates and their biological activities for plants

    Kume, T.; Nagasawa, N.; Matsuhashi, S.

    2000-01-01

    Radiation effects on carbohydrates such as chitosan, sodium alginate, carrageenan, cellulose, pectin have been investigated to improve the biological activities. These carbohydrates were easily degraded by irradiation and induced various kinds of biological activities such as anti-bacterial activity, promotion of plant growth, suppression of heavy metal stress, phytoalexins induction. Pectic fragments obtained from degraded pectin induced the phytoalexins such as glyceollins in soybean and pisatin in pea. The irradiated chitosan shows the higher elicitor activity for pisatin than that of pectin. For the plant growth promotion, alginate derived from brown marine algae, chitosan and ligno-cellulosic extracts show a strong activity. Kappa and iota carrageenan derived from red marine algae can promote growth of rice and the highest effect was obtained with kappa irradiated at 100 kGy. Some radiation degraded carbohydrates suppressed the damage of heavy metals on plants. The effects of irradiated carbohydrates on transportation of heavy metals have been investigated by PETIS (Positron Emitting Tracer Imaging System) and autoradiography using 48 V and 62 Zn. (author)

  5. Determination of seven trace elements in human milk, powdered cow's milk and infant foods by neutron activation analysis

    Grimanis, A.P.; Vassilaki-Grimani, M.; Alexiou, D.; Papadatos, C.

    1979-01-01

    The purpose of this study was to apply neutron activation analysis to the determination of seven trace elements (Co, Cr, Cu, Se, Zn, Rb and As) in colostrum, transitional and mature human milk as well as in powdered cow's milk and commercial infant foods, and thus to find out whether non-breast-fed infants received the same or different amounts of these trace elements as breast-fed ones. Ranges and averages for trace elements in mature human milk, expressed as microgrammes per gramme wet weight, varied as follows: Cr 0.018-0.040 and 0.027; Co 0.0013-0.0030 and 0.0020; Cu 0.38-0.50 and 0.46; Se 0.011-0.022 and 0.015; Zn 1.4-1.7 and 1.5; Rb 0.60-0.66 and 0.63; and As 0.0016-0.0060 and 0.0032. The mean concentrations of the essential trace elements Zn, Se, Cu, Cr and Co in colostrum were, respectively, 3.7, 3.2, 2.4, 1.8 and 1.7 times higher than those in mature human milk. No significant differences in Rb and As concentrations were found between colostrum and mature milk. Average values of Zn and Cu in transitional human milk were, respectively, 3.4 and 1.5 times higher than in mature milk. No significant differences for the rest of the elements were found between these two milk samples. The two milk formulas, half-cream and humanized, contained higher mean concentrations of Zn, Rb and As and similar or lower concentrations of Cr, Co and Se than mature human milk. Half-cream is deficient in Cu; mature human milk contains about 9 times more Cu than the half-cream cow's milk. Humanized milk contains a similar mean concentration of Cu as the mature milk. All examined infant foods contained similar or higher concentrations of all elements determined than did the mature human milk

  6. Trace elemental characterisation of different Indian tea samples by instrumental neutron activation analysis

    Lagad, Rupali A.; Alamelu, D.; Aggarwal, S.K.; Acharya, R.

    2010-01-01

    Determination of elemental content of different food materials is of importance since excess or deficiency of some of the elements have direct consequence to health of human beings. Tea is a common beverage consumed widely in India. India is one of the major country where good quality tea is produced. The tea plants are grown over a wide region of the country. It was of interest to study the elemental composition in tea samples from different geographical locations and to develop a suitable methodology to identify the geographical origin from the trace element profiles. With this objective, about 40 tea samples (both from plantations as well as from market) from the different locations in India viz. Assam, Munnar, Himachal Pradesh and Darjeeling were analyzed by INAA. About 150 mg of each of the sample packed in aluminium foil was irradiated in the self serve position of CIRUS reactor, BARC, for 3 to 5 hours at a neutron flux of ∼10 13 cm -2 s -1 . Along with the samples, Certified Reference Materials (CRMs) GBS-7(Tea leaves, as reference standard) and SRM-1515 (Apple leaves as control sample) were irradiated. Radioactive assay of the irradiated samples were carried out using a 40% relative efficiency HPGe detector coupled to 8K MCA and gamma-ray spectra were recorded for sufficient time for obtaining good counting statistics. Peak areas were determined using a peak-fit software PHAST. Concentrations of the different elements in tea samples were determined using relative method of INAA

  7. Neutron activation analysis of copper traces: a study for sodium correction factor

    Tripathi, A.B.R.; Bhadkambekar, C.A.; Basu, A.K.; Chattopadhyay, N.

    2007-01-01

    Peak ratio correction factors for accurate quantitative determination of copper by NAA via 64 Cu radioisotope in presence of high 24 Na radioactivities has been established. Copper is the principal element as a marker of bullet residues on targets in connection to forensic ballistics cases. Reliable and precise estimation of copper by NAA either via non-destructive way or by resorting to radiochemical separation is of importance in forensic analysis for arriving at definitive inferences. However, majority of samples originating from wearing apparels, paper, leather, skin, glass or any other metal exhibit matrices contain high levels of sodium. The NAA scheme for determination of copper rests on measurements of net counts at 511 KeV which is the positron annihilation peak of 64 Cu. 24 Na also contributes significantly exactly at 511 KeV of gamma energy albeit by different mechanism i.e., by pair production. Therefore, total signal at 511 KeV is contributed by both. The easiest approach for correct estimation of copper traces has been established by the peak ratio correction factor. This has significance as both 64 Cu and 24 Na have comparable half lives, hence, as such time gap measurements cannot improve the situation. The consistency of peak ratio correction factor could be established for a particular geometry. (author)

  8. Long-term effects of aided phytostabilisation of trace elements on microbial biomass and activity, enzyme activities, and composition of microbial community in the Jales contaminated mine spoils

    Renella, Giancarlo [Department of Soil Science and Plant Nutrition, University of Florence, Piazzale delle Cascine 28, I-50144 Florence (Italy)], E-mail: giancarlo.renella@unifi.it; Landi, Loretta; Ascher, Judith; Ceccherini, Maria Teresa; Pietramellara, Giacomo; Mench, Michel; Nannipieri, Paolo [Department of Soil Science and Plant Nutrition, University of Florence, Piazzale delle Cascine 28, I-50144 Florence (Italy)

    2008-04-15

    We studied the effectiveness of remediation on microbial endpoints, namely microbial biomass and activity, microbial and plant species richness, of an As-contaminated mine spoil, amended with compost (C) alone and in combination with beringite (B) or zerovalent iron grit (Z), to increase organic matter content and reduce trace elements mobility, and to allow Holcus lanatus and Pinus pinaster growth. Untreated spoil showed the lowest microbial biomass and activity and hydrolase activities, and H. lanatus as sole plant species, whereas the presented aided phytostabilisation option, especially CBZ treatment, significantly increased microbial biomass and activity and allowed colonisation by several plant species, comparable to those of an uncontaminated sandy soil. Microbial species richness was only increased in spoils amended with C alone. No clear correlation occurred between trace element mobility and microbial parameters and plant species richness. Our results indicate that the choice of indicators of soil remediation practices is a bottleneck. - Organo-mineral amendment and revegetation of a gold mine spoil increased microbial activity but did not increase microbial species richness.

  9. Long-term effects of aided phytostabilisation of trace elements on microbial biomass and activity, enzyme activities, and composition of microbial community in the Jales contaminated mine spoils

    Renella, Giancarlo; Landi, Loretta; Ascher, Judith; Ceccherini, Maria Teresa; Pietramellara, Giacomo; Mench, Michel; Nannipieri, Paolo

    2008-01-01

    We studied the effectiveness of remediation on microbial endpoints, namely microbial biomass and activity, microbial and plant species richness, of an As-contaminated mine spoil, amended with compost (C) alone and in combination with beringite (B) or zerovalent iron grit (Z), to increase organic matter content and reduce trace elements mobility, and to allow Holcus lanatus and Pinus pinaster growth. Untreated spoil showed the lowest microbial biomass and activity and hydrolase activities, and H. lanatus as sole plant species, whereas the presented aided phytostabilisation option, especially CBZ treatment, significantly increased microbial biomass and activity and allowed colonisation by several plant species, comparable to those of an uncontaminated sandy soil. Microbial species richness was only increased in spoils amended with C alone. No clear correlation occurred between trace element mobility and microbial parameters and plant species richness. Our results indicate that the choice of indicators of soil remediation practices is a bottleneck. - Organo-mineral amendment and revegetation of a gold mine spoil increased microbial activity but did not increase microbial species richness

  10. A critical review of nuclear activation techniques for the determination of trace elements in atmospheric aerosols, particulates and sludge samples

    Dams, R.

    1992-01-01

    Activation analysis is one of the major techniques for the determination of many minor and trace elements in a large variety of solid environmental and pollution samples, such as atmospheric aerosols, particulate emissions, fly ash, coal, incineration ash and sewage sludge, etc. Neutron activation analysis of total, inhalable or respirable airborne particulate matter collected on a filter or in a cascade impactor on some substrate, is very popular. By Instrumental Neutron Activation Analysis (INAA) up to 45 elements can be determined. The irradiation and counting procedures can be adapted to optimize the sensitivity for particular elements. The precision is largely governed by counting statistics and a high accuracy can be obtained after calibration with multi-elemental standards. Radiochemical Neutron Activation Analysis (RNAA) is applied only when extremely low limits of determination are required. Instrumental Photon Activation Analysis (IPAA) is complementary to INAA, since some elements of environmental interest can be determined which do not produce appropriate radionuclides by neutron irradiation. Charged Particle Activation Analysis (CPAA) is used in particular circumstances such as for certification purposes or coupled to radiochemical separations for extremely low concentrations. (author)

  11. A comparative study of minor and trace elements in human, animal and commercial milk samples by neutron activation analysis

    Garg, A.N.; Weginwar, R.G.; Chutke, N.L.

    1993-01-01

    Human, animal (cow, buffalo and goat) and commercial milk powders (for infants and adults) have been analyzed for 5 minor (Na, K, Mg, Cl and P) and 13 trace elements (Cr, Mn, Fe, Co, Cu, Zn, Cd, Hg, As, Se, Sb, Cs and Br) by instrumental and radiochemical neutron activation. Milk standards NIST SRM 1549 and IAEA A-11 along with diet standards RM 8431a and IAEA H-9 were also analyzed for quality assurance. The method involves thermal neutron irradiation for 10 m, 1 h, 6 h and 1 week in a reactor followed by high resolution γ-spectrometry. Concentrations of Fe, Co, Zn, Sb and Se were also determined by radiochemical solvent extraction. Mean concentrations of Na, K, Mg, P, Cl, Fe, Mn and Cu in human milk (colostrum) are comparable with that of a WHO/IAEA study. It has, however, lower contents of toxic trace elements (Cr, Cd, Hg, Br, Se, Sb and As) compared to breast tissue from the same area. Cow milk is richer in Na, K, Cl, Mn and Se but it has comparable amounts of Mg, Zn, Br, Fe and Sb with respect to breast milk. Significant differences have been observed for elemental concentrations of Na, K, P and Fe in commercial formula milk powders for infants and adults. Infant's milk powders contain all the nutrient elements in balanced amounts required for the higher growth rate of a child. (author) 41 refs.; 2 figs.; 3 tabs

  12. Degradation kinetics and mechanism of trace nitrobenzene by granular activated carbon enhanced microwave/hydrogen peroxide system.

    Tan, Dina; Zeng, Honghu; Liu, Jie; Yu, Xiaozhang; Liang, Yanpeng; Lu, Lanjing

    2013-07-01

    The kinetics of the degradation of trace nitrobenzene (NB) by a granular activated carbon (GAC) enhanced microwave (MW)/hydrogen peroxide (H202) system was studied. Effects of pH, NB initial concentration and tert-butyl alcohol on the removal efficiency were examined. It was found that the reaction rate fits well to first-order reaction kinetics in the MW/GAC/H202 process. Moreover, GAC greatly enhanced the degradation rate of NB in water. Under a given condition (MW power 300 W, H202 dosage 10 mg/L, pH 6.85 and temperature (60 +/- 5)degrees C), the degradation rate of NB was 0.05214 min-1when 4 g/L GAC was added. In general, alkaline pH was better for NB degradation; however, the optimum pH was 8.0 in the tested pH value range of 4.0-12.0. At H202 dosage of 10 mg/L and GAC dosage of 4 g/L, the removal of NB was decreased with increasing initial concentrations of NB, indicating that a low initial concentration was beneficial for the degradation of NB. These results indicated that the MW/GAC/H202 process was effective for trace NB degradation in water. Gas chromatography-mass spectrometry analysis indicated that a hydroxyl radical addition reaction and dehydrogenation reaction enhanced NB degradation.

  13. Carbon Dioxide Information Analysis Center and World Data Center-A for atmospheric trace gases: FY 1993 activities

    Cushman, R.M. [Oak Ridge National Lab., TN (United States). Carbon Dioxide Information Analysis Center; Stoss, F.W. [Oak Ridge National Lab., TN (United States). Carbon Dioxide Information Analysis Center]|[Univ. of Tennessee, Knoxville, TN (United States). Energy, Environment, and Resources Center

    1994-01-01

    During the course of a fiscal year, Oak Ridge National Laboratory`s Carbon Dioxide Information Analysis Center (CDIAC) distributes thousands of specialty publications-numeric data packages (NDPs), computer model packages (CMPs), technical reports, public communication publications, newsletters, article reprints, and reference books-in response to requests for information related to global environmental issues, primarily those pertaining to climate change. CDIAC`s staff also provide technical responses to specific inquiries related to carbon dioxide (CO{sub 2}), other trace gases, and climate. Hundreds of referrals to other researchers, policy analysts, information specialists, or organizations are also facilitated by CDIAC`s staff. This report provides an account of the activities accomplished by CDIAC (including World Data Center-A for Atmospheric Trace Gases) during the period October 1, 1992, to September 30, 1993. An organizational overview of CDIAC and its staff is supplemented by a detailed description of inquiries received and CDIAC`s response to those inquiries. An analysis and description of the preparation and distribution of NDPS, CMPS, technical reports, newsletters, fact sheets, specialty publications, and reprints are provided. Comments and descriptions of CDIAC`s information management systems, professional networking, and special bilateral agreements are also presented.

  14. Carbon Dioxide Information Analysis Center and World Data Center-A for atmospheric trace gases: FY 1993 activities

    Cushman, R.M.; Stoss, F.W.; Univ. of Tennessee, Knoxville, TN

    1994-01-01

    During the course of a fiscal year, Oak Ridge National Laboratory's Carbon Dioxide Information Analysis Center (CDIAC) distributes thousands of specialty publications-numeric data packages (NDPs), computer model packages (CMPs), technical reports, public communication publications, newsletters, article reprints, and reference books-in response to requests for information related to global environmental issues, primarily those pertaining to climate change. CDIAC's staff also provide technical responses to specific inquiries related to carbon dioxide (CO 2 ), other trace gases, and climate. Hundreds of referrals to other researchers, policy analysts, information specialists, or organizations are also facilitated by CDIAC's staff. This report provides an account of the activities accomplished by CDIAC (including World Data Center-A for Atmospheric Trace Gases) during the period October 1, 1992, to September 30, 1993. An organizational overview of CDIAC and its staff is supplemented by a detailed description of inquiries received and CDIAC's response to those inquiries. An analysis and description of the preparation and distribution of NDPS, CMPS, technical reports, newsletters, fact sheets, specialty publications, and reprints are provided. Comments and descriptions of CDIAC's information management systems, professional networking, and special bilateral agreements are also presented

  15. A Monte Carlo Ray Tracing Model to Improve Simulations of Solar-Induced Chlorophyll Fluorescence Radiative Transfer

    Halubok, M.; Gu, L.; Yang, Z. L.

    2017-12-01

    A model of light transport in a three-dimensional vegetation canopy is being designed and evaluated. The model employs Monte Carlo ray tracing technique which offers simple yet rigorous approach of quantifying the photon transport in a plant canopy. This method involves simulation of a chain of scattering and absorption events incurred by a photon on its path from the light source. Implementation of weighting mechanism helps avoid `all-or-nothing' type of interaction between a photon packet and a canopy element, i.e. at each interaction a photon packet is split into three parts, namely, reflected, transmitted and absorbed, instead of assuming complete absorption, reflection or transmission. Canopy scenes in the model are represented by a number of polygons with specified set of reflectances and transmittances. The performance of the model is being evaluated through comparison against established plant canopy reflectance models, such as 3D Radiosity-Graphics combined model which calculates bidirectional reflectance distribution function of a 3D canopy scene. This photon transport model is to be coupled to a leaf level solar-induced chlorophyll fluorescence (SIF) model with the aim of further advancing of accuracy of the modeled SIF, which, in its turn, has a potential of improving our predictive capability of terrestrial carbon uptake.

  16. Report on our activities to spread knowledge about radiation in Musashi Institute of Technology

    Okada, Yukiko

    2007-01-01

    In Musashi Institute of Technology, radiation knowledge spread activities are performed twice per year. One is 'the science experience classroom which children enjoy.' Another is 'the open school which studies atomic power'. The writer participated in the 'life and radiation' project as a WEN member, and has performed the radiation knowledge spread activities to a citizen. In this paper, these activities are introduced and the necessity and problem of radiation knowledge spread activities are considered. (author)

  17. Our activities to spread knowledge about radiation in Fukushima 2012

    Okada, Yukiko

    2013-01-01

    Atomic Energy Research Laboratory, Tokyo City University, has a research reactor in decommissioning process. We want to support works for the recovery from the Fukushima nuclear disaster applying our knowledge obtained in the decommissioning works. Recent activities include: (1) Performance of Ge detectors has been improved and each detector has been connected to a MCA and a computer to be used in research, education and works at Fukushima. (2) We are working for evaluation of the uniformity of standard environmental materials to be used in the analysis of radioactivity. (3) We have made educations on radioactivity at 32 sites in 2012 for pupils, teachers and general citizens. In these educations, observation of radioactivity by cloud chamber and radiation measurement were made after the lecture. Some groups visited Atomic Energy Research Laboratory to study radiation measurement with shielding materials. (J.P.N.)

  18. Active control of noise radiation from vibrating structures

    Mørkholt, Jakob

    developed, based on the theory of radiation filters for estimating the sound radiation from multimodal vibrations. This model has then been used in simulations of optimal feedback control, with special emphasis of the stability margins of the optimal control scheme. Two different methods of designing...... optimal and robust discrete-time feedback controllers for active vibration control of multimodal structures have been compared. They have been showed to yield controllers with identical frequency response characteristics, even though they employ completely different methods of numerical solutions...... and result in different representations of the controllers. The Internal Model Control structure combined with optimal filtering is suggested as an alternative to state space optimal control techniques for designing robust optimal controllers for audio frequency vibration control of resonant structures....

  19. Introduction of the activity of the radiation safety for KOMAC

    Min, Yi Sub; Park, Sung Kyun; Park, Jeong Min; Cho, Yong Sub [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The 100 MeV linear proton accelerator as well as the various types of the ion accelerator have been operated and developed in KOMAC. These accelerators are classified as a radiation generator by the nuclear law of Korea. The operation of these accelerators included in the KOMAC site should be approved by Nuclear Safety and Security Committee (NSSC). This paper introduces the activity in terms of the radiation safety for these accelerator operations and their future plan. The model of the ion beam accelerator for analysis installed in KOMAC is a 5SDH-2, produced by National Electrostatics Corporation. This ion beam accelerator, devolved from Korea Institute of Geoscience and Mineral Resources (KIGAM), consists of two ion source, accelerating tanks and four beamlines. Ions in the ion beam accelerator are accelerated using a tandem method, that is, ions accelerated have been drawn out by the negative ions from the ion source and then changed into positive ions in the acceleration tube intermediate.

  20. Present Status and Near Term Activities for the ExoMars Trace Gas Orbiter.

    Svedhem, H.; Vago, J. L.

    2017-12-01

    The ExoMars 2016 mission was launched on a Proton rocket from Baikonur, Kazakhstan, on 14 March 2016 and arrived at Mars on 19 October 2016. The spacecraft is now performing aerobraking to reduce its orbital period from initial post-insertion orbital period of one Sol to the final science orbit with a 2 hours period. The orbital inclination will be 74 degrees. During the aerobraking a wealth of data has been acquired on the state of the atmosphere along the tracks between 140km and the lowest altitude at about 105 km. These data are now being analysed and compared with existing models. In average TGO measures a lower atmospheric density than predicted, but the numbers lay within the expected variability. ExoMars is a joint programme of the European Space Agency (ESA) and Roscosmos, Russia. It consists of the ExoMars 2016 mission with the Trace Gas Orbiter, TGO, and the Entry Descent and Landing Demonstrator, EDM, named Schiaparelli, and the ExoMars 2020 mission, which carries a lander and a rover. The TGO scientific payload consists of four instruments: ACS and NOMAD, both infrared spectrometers for atmospheric measurements in solar occultation mode and in nadir mode, CASSIS, a multichannel camera with stereo imaging capability, and FREND, an epithermal neutron detector to search for subsurface hydrogen (as proxy for water ice and hydrated minerals). The launch mass of the TGO was 3700 kg, including fuel. In addition to its scientific measurements TGO will act as a relay orbiter for NASA's landers on Mars and as from 2021 for the ESA-Roscosmos Rover and Surface Station.

  1. Neutron activation and PIXE analysis of oyster tissues cultivated at different ocean depths for trace elements

    Fukushima, M.; Nakano, Y.; Chatt, A.

    2005-01-01

    Difference in trace element concentrations in oyster tissues cultivated in Japan on hanging ropes at different sea depths were investigated using INAA and PIXE. Three groups of oyster were collected from a single rope at 1 m, 6 m, and 11 m depths. From each group, five oysters were chosen and removed from the shell after washing in tap water. Two groups of organ, namely hepatopancreas and muscle, and gill and mantle were separated from soft tissues, freeze-dried, and pulverized. One portion of the powdered samples was irradiated for a short time at the Dalhousie University SLOWPOKE-2 reactor in Canada for Ag and Se analysis. Another portion was irradiated for one hour in Kyoto University Reactor in Osaka, Japan for Fe, Rb, Sc, and Zn analysis. The third portion was digested in a microwave oven after the addition of an indium solution (as an internal standard) and concentrated nitric acid for analysis by PIXE. More than twenty elements were determined by PIXE. The organs in oysters have different roles. For example, hepatopancreas and muscle are thought to accumulate elements after ingestion of plankton from sea water while gill and mantle are always in contact with sea water. As a result, there were differences in levels of some elements between the two groups of organ. In addition, levels of most elements were found to be depth dependent. The variations in Fe and Zn concentrations of the two organ groups at 3 different depths are shown in Table 1. Details of the method and results will be presented.

  2. Analysis of trace elements in ceramic prints on automobile glasses for forensic examination using high-energy synchrotron radiation x-ray fluorescence spectrometry

    Nishiwaki, Yoshinori; Takatsu, Masahisa; Miyamoto, Naoki; Watanabe, Seiya; Shimoda, Osamu; Muratsu, Seiji; Nakanishi, Toshio; Nakai, Izumi

    2007-01-01

    This study revealed that high-energy SRXRF (synchrotron radiation X-ray fluorescence spectrometry) utilizing 75.5 keV X-rays of SPring-8 is a powerful technique for trace elemental analysis of ceramic prints on automotive glasses for forensic examination. Fragments of 99 ceramic prints were collected from automobiles of various manufacturers, types and model years. Their major heavy element-components were found to be either Pb or Bi. Because of recent environment protection movement for lead-free material, there was a tendency of the shift of material from the Pb Type to the Bi Type with years of the production. A utilization of 75.5 keV X-rays as excitation source allowed us to detect trace heavy-elements, such as Sb, La, Ce, Hf and W, as well as relatively light-elements, such as V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr and Mo, in samples using K series of XRF emission lines. XRF intensities of these elements normalized by those of the major heavy-elements (Pb or Bi) became characteristic finger prints, showing the identity of each sample with a size of less than 0.5x0.5 mm 2 . The mean relative standard deviations of the normalized XRF intensities measured for the three fragments of each sample were less than 9.3%. These results show that the ceramic prints on automobile glasses contain rich elemental information for discrimination, and therefore the materials can be important evidence for practical forensic examinations. (author)

  3. A Relationship Between the Solar Rotation and Activity Analysed by Tracing Sunspot Groups

    Ruždjak, Domagoj; Brajša, Roman; Sudar, Davor; Skokić, Ivica; Poljančić Beljan, Ivana

    2017-12-01

    The sunspot position published in the data bases of the Greenwich Photoheliographic Results (GPR), the US Air Force Solar Optical Observing Network and National Oceanic and Atmospheric Administration (USAF/NOAA), and of the Debrecen Photoheliographic Data (DPD) in the period 1874 to 2016 were used to calculate yearly values of the solar differential-rotation parameters A and B. These differential-rotation parameters were compared with the solar-activity level. We found that the Sun rotates more differentially at the minimum than at the maximum of activity during the epoch 1977 - 2016. An inverse correlation between equatorial rotation and solar activity was found using the recently revised sunspot number. The secular decrease of the equatorial rotation rate that accompanies the increase in activity stopped in the last part of the twentieth century. It was noted that when a significant peak in equatorial rotation velocity is observed during activity minimum, the next maximum is weaker than the previous one.

  4. Determination of the levels of trace elements in ten years old children from Antofagasta city, Chile by neutron activation analysis

    Gras, N.; Munoz, A.L.; Jamett J, A.; Pena C, L.; Santander M, M.

    1988-01-01

    The levels of trace elements in scalp hair of ten years old children of Antofagasta city were determined. For this study, the city was divided in convenient areas. Comparisons between levels of concentrations considering residential areas, sex, values obtained for children of Santiago, and the ranges given in the literature were established. Fifty samples of hair were analyzed by instrumental neutron activation analisis. The elements selected were: As, Br, Co, Cr, Cu, Fe, Hg, K, Na. Sb, and Zn. The effectiveness of wash procedure before irradiation was studied. Ten samples were taken with sufficient amount of hair and each was divided into two, only one of them was washed and both were analyzed. The levels of concentrations were compared. (author)

  5. Evaluation of trace elements in human milk from patients of the Chile metropolitan area by neutron activation analysis

    Luco Mujica, H.

    1983-01-01

    Human milk samples from 23 patients of the Metropolitan Area of Santiago, Chile, were collected and analysed for the determination of their trace element content. Samples were collected from each patient at the third, fifth and thirtieth day post-partum. The samples were analyzed by neutron activation analysis in its instrumental form, for the determination of Cr, Fe, Co, Zn, Se and Rb, and radiochemically for the analysis of Cu and As. It was observed than those elements classified as essential for the normal growth of child, presented concentration levels in agreement with the values recommended by International Health Organizations. Arsenic was not detected in the samples analyzed. It was found not significant difference between the three types of milk analyzed (calostrum, transition and madure), with the exception of Rb and Zn. (Author)

  6. Trace element determination in plant material by means of instrumental neutron activation analysis (INAA) with special reference to molybdenum

    Schnier, C.; Schnug, E.

    1981-01-01

    The instrumental neutron activation analysis (INAA) permits a non-destructive multielement determination of minute trace element concentrations in organic material. No sample preparation except drying is required. Especially for the determination of molybdenum the INAA offers great advantages compared to the methods used in agricultural chemistry where complicated enrichment and extraction steps are needed. Contamination by reagents or loss of elements are not potential sources of errors. The principle, the advantages and disadvantages of INAA are described. The method is demonstrated with the example of celery samples from an experiment with five different nitrogen fertilizers on contaminated soil and of cabbage samples from an uncontaminated region. Besides molybdenum, 19 other elements (Na, K, Ca, Sc, Cr, Fe, Co, Zn, As, Se, Br, Rb, Cd, Sb, Ba, La, W, Au, Th) are determined. (orig.) [de

  7. Study of selected trace elements in cancerous and non-cancerous human breast tissues using neutron activation analysis

    Ebrahim, A. M.

    2006-03-01

    This study was performed to investigate the influence of cancer on selected trace elements among sudanese patients with confirmed breast cancer. Eighty samples of cancerous and normal tissues (total of one hundred and sixty) were obtained from the same breast of the same subject from different hospitals in Khartoum State. Samples were freeze dried and analyzed using neutron activation analysis (NAA). Neutron irradiations were performed at Egypt second research reactor with a maximum thermal flux of 2.37 Χ 10 14 n cm -2 s -1 . To examine if there was any difference in the concentrations of elements from normal and malignant tissues; Wilcox on signed ranks test was used. It was found that Al, Mn, Mg, Se, Zn, and Cr elements from the malignant tissues are significantly elevated (p 0.05). The results obtained have shown consistency with results obtained by some previous studies, however, no data could be found for the elements Mg, Cr, and Sc.(Author)

  8. Some investigation on trace elements content of Iranian breads using neutron activation analysis and atomic absorption spectroscopy

    Gharib, A.; Fatemi, K.; Moazezi, A.; Mahmoodzadeh, A.; Koushkestani, R.

    1988-01-01

    Since bread is consumed as a principal dietary staple by the majority of Iranian communities, actual natural portion of required protein and energy are provided via bread. Therefore, with respect to this matter, a considerable amount of needed minerals must also be met through this way. Literature survey indicates some elemental deficiencies as the result of consumption of bread in Iran. On the other hand, essentiality of these elements to human which are mostly in the range of trace amounts, makes this investigation very much important and interesting from both sides, nutritionally and instrumentally. To meet the above requirements, applications of very sensitive analytical tools are unavoidable. Hence, atomic absorption spectroscopy and neutron activation analysis both RNAA and INAA are employed. Results are controversial and constructive

  9. Tracing the Construction of Mathematical Activity with an Advanced Graphing Calculator to Understand the Roles of Technology Developers, Teachers and Students

    Hillman, Thomas

    2014-01-01

    This article examines mathematical activity with digital technology by tracing it from its development through its use in classrooms. Drawing on material-semiotic approaches from the field of Science and Technology Studies, it examines the visions of mathematical activity that developers had for an advanced graphing calculator. It then follows the…

  10. Active and Passive 3D Vector Radiative Transfer with Preferentially-Aligned Ice Particles

    Adams, I. S.; Munchak, S. J.; Pelissier, C.; Kuo, K. S.; Heymsfield, G. M.

    2017-12-01

    To support the observation of clouds and precipitation using combinations of radars and radiometers, a forward model capable of representing diverse sensing geometries for active and passive instruments is necessary for correctly interpreting and consistently combining multi-sensor measurements from ground-based, airborne, and spaceborne platforms. As such, the Atmospheric Radiative Transfer Simulator (ARTS) uses Monte Carlo integration to produce radar reflectivities and radiometric brightness temperatures for three-dimensional cloud and precipitation input fields. This radiative transfer framework is capable of efficiently sampling Gaussian antenna beams and fully accounting for multiple scattering. By relying on common ray-tracing tools, gaseous absorption models, and scattering properties, the model reproduces accurate and consistent radar and radiometer observables. While such a framework is an important component for simulating remote sensing observables, the key driver for self-consistent radiative transfer calculations of clouds and precipitation is scattering data. Research over the past decade has demonstrated that spheroidal models of frozen hydrometeors cannot accurately reproduce all necessary scattering properties at all desired frequencies. The discrete dipole approximation offers flexibility in calculating scattering for arbitrary particle geometries, but at great computational expense. When considering scattering for certain pristine ice particles, the Extended Boundary Condition Method, or T-Matrix, is much more computationally efficient; however, convergence for T-Matrix calculations fails at large size parameters and high aspect ratios. To address these deficiencies, we implemented the Invariant Imbedding T-Matrix Method (IITM). A brief overview of ARTS and IITM will be given, including details for handling preferentially-aligned hydrometeors. Examples highlighting the performance of the model for simulating space-based and airborne measurements

  11. A simple chemical method for the separation of phosphorus interfering the trace element determinations by neutron activation analysis in high doped silicon wafers

    Wagler, H.; Flachowsky, J.

    1986-01-01

    Neutron activation analysis is one of the most available method for the determination of trace elements, but in the case of P-doped silicon wafers the 32 P-activity interferes the gamma spectrometry. It is not possible to determine the trace elements without chemical manipulations. On the other hand, time consuming chemical separations should be avoided. Therefore, a simple and rapid P-separation method has to be developed, in which the following twelve trace elements should be taken into consideration: Ag, As, Au, Co, Cr, Cu, Fe, Mo, Na, Sb, W, and Zn. After acid oxidative dissolution of the activated sample, P is present as phosphate ion. The phosphate ion is removed by precipitation as BiPO 4 . (author)

  12. Tracing attention and the activation flow in spoken word planning using eye-movements

    Roelofs, A.P.A.

    2008-01-01

    The flow of activation from concepts to phonological forms within the word production system was examined in 3 experiments. In Experiment 1, participants named pictures while ignoring superimposed distractor pictures that were semantically related, phonologically related, or unrelated. Eye movements

  13. Activity modeling under uncertainty by trace of objects in smart homes

    National Aeronautics and Space Administration — A typical resident of a smart home can be an Alzheimer patient that forgets sometimes to complete the activities that he begins. The key point to assist the smart...

  14. Minor and trace elements in melanins determined by neutron activation analysis

    Kochanska-Dziurowicz, A.A.; Wilczok, T.; Mosulishvili, L.; Kharabadze, N.

    1986-01-01

    The presence of Au, Br, Sb, Ag, Fe, Zn, Co, Cr, Ni, Hg and Sn determined by neutron activation analysis was demonstrated in melanins isolated from human dark hair, banana peels or prepared synthetically from tyrosine. (author)

  15. Stanford Synchrotron Radiation Laboratory activity report for 1987

    Robinson, S.; Cantwell, K. [eds.

    1988-12-31

    During 1987, SSRL achieved many significant advances and reached several major milestones utilizing both SPEAR and PEP as synchrotron radiation sources as described in this report. Perhaps the following two are worthy of particular mention: (1) SPEAR reached an all time high of 4,190 delivered user-shifts during calendar year 1987, highlights of the many scientific results are given; (2) during a 12 day run in December of 1987, PEP was operated in a low emittance mode (calculated emittance 6.4 nanometer-radians) at 7.1 GeV with currents up to 33 mA. A second undulator beam line on PEP was commissioned during this run and used to record many spectra showing the extremely high brightness of the radiation. PEP is now by far the highest brightness synchrotron radiation source in the world. The report is divided into the following sections: (1) laboratory operations; (2) accelerator physics programs; (3) experimental facilities; (4) engineering division; (5) conferences and workshops; (6) SSRL organization; (7) experimental progress reports; (8) active proposals; (9) SSRL experiments and proposals by institution; and (10) SSRL publications.

  16. Weather Effects on the Patterns of People's Everyday Activities: A Study Using GPS Traces of Mobile Phone Users

    Leong, Tuck W.; Sekimoto, Yoshihide; Shibasaki, Ryosuke

    2013-01-01

    This study explores the effects that the weather has on people's everyday activity patterns. Temperature, rainfall, and wind speed were used as weather parameters. People's daily activity patterns were inferred, such as place visited, the time this took place, the duration of the visit, based on the GPS location traces of their mobile phones overlaid upon Yellow Pages information. Our analysis of 31,855 mobile phone users allowed us to infer that people were more likely to stay longer at eateries or food outlets, and (to a lesser degree) at retail or shopping areas when the weather is very cold or when conditions are calm (non-windy). When compared to people's regular activity patterns, certain weather conditions affected people's movements and activities noticeably at different times of the day. On cold days, people's activities were found to be more diverse especially after 10AM, showing greatest variations between 2PM and 6PM. A similar trend is observed between 10AM and midnight on rainy days, with people's activities found to be most diverse on days with heaviest rainfalls or on days when the wind speed was stronger than 4 km/h, especially between 10AM–1AM. Finally, we observed that different geographical areas of a large metropolis were impacted differently by the weather. Using data of urban infrastructure to characterize areas, we found strong correlations between weather conditions upon people's accessibility to trains. This study sheds new light on the influence of weather conditions on human behavior, in particular the choice of daily activities and how mobile phone data can be used to investigate the influence of environmental factors on urban dynamics. PMID:24367481

  17. SCHOOL, CULTURE & MOVEMENT : SUBJECTS/ACTORS FACE THE TRACES OF THEIR OWN ACTIVITY WHEN CREATING ALBUMS

    Nadine Pairis

    2015-04-01

    Full Text Available This article concerns pupils' activity operated from the theoretical and methodological framework of data analysis of the "process of action" (Theureau, 2004 supporting on activity tracks (what emerges from the pre-reflexive consciousness and video recordings proceeded with individual interviews questioning the actors about their work : creation of albums into two classes of cycle 2 (one of them is an experimental artistic and cultural educational classroom with the help of an author/illustrator. The understanding of pupil’s activity answers the hypothesis of getting to work with creativity (Vygotski, 1930 in studying the "school well-being", the discourse analysis (case of Ramone who, in 2013, is not involved in the album creation while in 2014 he does not want to go out for a break before having finished the activity of visual art as well as the posture of their bodies at a moment of attentive listening. The results reveal that pupils need more movement than being in stand by (Jorro, 2013; Dewey 1934, in exploring their relationship to the space children become aware of the other ones (action vs passivity. The analysis of the pupils’ activity puts into perspective the impact of the artistic and cultural practices on learnings and movement (performance of their musical tale -moving in space with big-sized illustrations-, graphic movement : not only in writing but in positioning their body to accustom them to feel it before it hurts them as means of expression and cultural fact.

  18. Fluorescence-based monitoring of in vivo neural activity using a circuit-tracing pseudorabies virus.

    Andrea E Granstedt

    Full Text Available The study of coordinated activity in neuronal circuits has been challenging without a method to simultaneously report activity and connectivity. Here we present the first use of pseudorabies virus (PRV, which spreads through synaptically connected neurons, to express a fluorescent calcium indicator protein and monitor neuronal activity in a living animal. Fluorescence signals were proportional to action potential number and could reliably detect single action potentials in vitro. With two-photon imaging in vivo, we observed both spontaneous and stimulated activity in neurons of infected murine peripheral autonomic submandibular ganglia (SMG. We optically recorded the SMG response in the salivary circuit to direct electrical stimulation of the presynaptic axons and to physiologically relevant sensory stimulation of the oral cavity. During a time window of 48 hours after inoculation, few spontaneous transients occurred. By 72 hours, we identified more frequent and prolonged spontaneous calcium transients, suggestive of neuronal or tissue responses to infection that influence calcium signaling. Our work establishes in vivo investigation of physiological neuronal circuit activity and subsequent effects of infection with single cell resolution.

  19. Highlights of IAEA activities in the field of radiation application

    Machi, S.

    1994-01-01

    In IAEA's major programme of Nuclear Applications, the activities performed are divided into four areas: food and agriculture, industry and earth science, human health, and physical and chemical sciences. These activities involve co-operation with FAO, WHO, UNIDO and UNEP, and have close link with the technical assistance programme. About 60% of the technical assistance projects are implemented in the field of nuclear applications. The purpose of the nuclear application programme is to develop technologies useful for environmental protection and sustainable development, to support R and D programmes of developing countries, to develop new applications of nuclear techniques. Major activities in food and agriculture are the application of radiation and isotopes, controling insects, preserving food, soil fertility and crop production, and improving animal production and the use of radiation with biotechnology for plant mutation breeding aiming at environmentally friendly and sustainable food production. In the human health programme emphasis is given to nuclear medicine, cancer therapy and nutrition. Today, only 35% of all developing countries have radiotherapy facilities. Activities, therefore, focus on strengthening clinical radiotherapy in such countries. In the field of industry and earth science, flue gas cleaning by electron beams, pollution monitoring using nuclear analytical techniques, nucleonic control systems for industries, and water resource exploration are major projects assisting developing countries. As of 1994 the IAEA will launch 12 new and promising Model Projects for developing Member States which will be of benefit to their economies and raising of their standard of living. In this paper the highlights of the above mentioned IAEA activities are presented. (author)

  20. Background levels of some trace elements in egyptian soils determined by neutron activation analysis

    Abdel-Sabour, M F [Soil pollution unit, Soil and water dept., Nuclear res.center, Cairo (Egypt); Abdel-Haleen, A S [Hot Labs, Atomic Energy Authority, Cairo (Egypt); Zohny, E E [Physics Dept. Faculty of Science, Cairo Univ. Ain shams Univ., Cairo, (Egypt); Sroor, A [Nuclear Physics Dep., Faculty of Girls, Ain Shams Univ., Cairo (Egypt); Zaghloul, R [Mubarak city for scientific research and technology, Ministry of scientific research, Cairo, (Egypt)

    1997-12-31

    As part of a research program on the influence of agricultural practices and activities on soil content of heavy metals. The present work was carried out to investigate the feasibility of instrumental neutron activation analysis for this purpose. Elements studied were, Fe, Zn, Co, Sc, Sb, As, Cd, Hg and Cr. The soil samples analyzed were from different locations to represent different land uses and types. Results revealed that As, Cd and Hg show a pronounced accumulation in soils especially those exposed to industrial and organic wastes disposal. 2 tabs.

  1. Effect of radiation on proteo-hormones activity

    Mikulaj, L.

    1975-05-01

    Samples of pituitary hormones were irradiated by a 60 Co source. A dose rate of 1.0-1.1 Mrad/hour and the doses of 0.5, 2.5 and 12.5 Mrad were used. The hormone preparations in the dry solid state or in solution were sealed into glass ampules. After sterilization they were kept at 4 0 C until the biological activity had been tested. The biological activity of thyroid stimulating hormone TSH, subjected to a sterilizing dose of 2.5 Mrad of gamma radiation, was found to have decreased when tested 3-5 months after irradiation. TSH remained fully active for up to 1 month after sterilization. The activity of vasopressin dropped off markedly during the 3-4 week period after irradiation. Biological activity of growth hormone tested shortly after irradiation was found to be unaffected. The activities of adrenocorticotropic hormone, human menopausal gonadotropin and luteinizing hormone were not affected. The experiments can be considered promising since they show that pituitary proteohorm, one preparations in the solid state may be sterilized. The stability on storage needs, however, to be carefully checked individually for every single hormone

  2. Novel Concrete Chemistry Achieved with Low Dose Gamma Radiation Curing and Resistance to Neutron Activation

    Burnham, Steven Robert

    As much as 50% of ageing-related problems with concrete structures can be attributed to con-struction deficiencies at the time of placement. The most influential time affecting longevity of concrete structures is the curing phase, or commonly the initial 28 days following its placement. A novel advanced atomistic analysis of novel concrete chemistry is presented in this dissertation with the objective to improve concrete structural properties and its longevity. Based on experiments and computational models, this novel concrete chemistry is discussed in two cases: (a) concrete chemistry changes when exposed to low-dose gamma radiation in its early curing stage, thus improving its strength in a shorter period of time then curing for the conventional 28 days; (b) concrete chemistry is controlled by its atomistic components to assure strength is not reduced but that its activation due to long-term exposure to neutron flux in nuclear power plants is negligible. High dose gamma radiation is well documented as a degradation mechanism that decreases concrete's compressive strength; however, the effects of low-dose gamma radiation on the initial curing phase of concrete, having never been studied before, proved its compressive strength increases. Using a 137 Cs source, concrete samples were subjected to gamma radiation during the initial curing phase for seven, 14, and 28 days. The compressive strength after seven days is improved for gamma cured concrete by 24% and after 14 days by 76%. Concrete shows no improvement in compressive strength after 28 days of exposure to gamma radiation, showing that there is a threshold effect. Scanning Electron Microscopy is used to examine the microstructure of low-dose gamma radiation where no damage to its microstructure is found, showing no difference between gamma cured and conventionally cured concrete. Molecular dynamics modeling based on the MOPAC package is used to study how gamma radiation during the curing stage improves

  3. Preliminary radiation-oxidizing treatment influence on radiation-catalytic activity of zirconium during water decomposition process

    Garibov, A.A.; Aliyev, A.G.; Agayev, T.N.; Aliyev, S.M.; Velibekova, G.Z.

    2004-01-01

    The study of physical-chemical processes proceeding in contact of metal constructional materials nuclear reactors with water at simultaneous influence of temperature and radiation represents the large interest at the decision of problems material authority and safety of work of nuclear -power installations [1-2]. One of the widely widespread materials of active zone nuclear reactors is metal zirconium and its alloys. The influence of preliminary radiation processing on radiation, radiation -thermal and thermal processes of accumulation of molecular hydrogen and oxidation zirconium in contact with water is investigated at T=673 K and ρ=5mg/sm 3 [3-4]. Initial samples zirconium previously has been exposed by an irradiation in medium H 2 O 2 at D=20-410 kGy. The contribution of radiation processes in these contacts in process thermo-radiation decomposition of water and oxidation of materials of zirconium is revealed. It is established that the interaction of Zr metal, preliminary treated by radiation, with water at radiation -heterogeneous processes leads to passivity of a surface. The rate meanings of thermal, radiation -thermal processes and radiation-chemical yields of hydrogen are determined. It is revealed, that at radiation-heterogeneous processes in system Zr +H 2 O (ρ =5mg/sm 3 T=673 K) the increase of the absorbed doze up to 123 kGy results to reduction of a radiation -chemical yield of molecular hydrogen. The further increase of the absorbed doze results to increase of a radiation -chemical yield of hydrogen. The observable effect at the preliminary radiation of zirconium is connected to formation of oxide phase on a surface. The mechanism of radiation -heterogeneous processes proceeding in system Zr+H 2 O is suggested. (author)

  4. Tracing Attention and the Activation Flow of Spoken Word Planning Using Eye Movements

    Roelofs, Ardi

    2008-01-01

    The flow of activation from concepts to phonological forms within the word production system was examined in 3 experiments. In Experiment 1, participants named pictures while ignoring superimposed distractor pictures that were semantically related, phonologically related, or unrelated. Eye movements and naming latencies were recorded. The…

  5. Effect of trace amounts of polyacrylamide (PAM) on long-term performance of activated sludge

    Luo, Yuan-ling; Yang, Zhao-hui; Xu, Zheng-yong; Zhou, Ling-jun; Zeng, Guang-ming; Huang, Jing; Xiao, Yong; Wang, Li-ke

    2011-01-01

    This study aims at evaluating the impacts of PAM addition on activated sludge performance. Four lab-scale sequencing batch reactors (SBRs), each with a working volume of 3 L, were investigated with different PAM concentrations. Experiments were conducted with varying organic loading rate and the sludge volume index (SVI), particle size, zeta potential, specific oxygen uptake rate (SOUR), mixed liquor suspended solids (MLSS), COD and ammonium removal efficiency were monitored over a 105-day period. The results showed that all of the PAM addition not only improved the removal efficiencies of COD and ammonium, but also exhibited some advantages on sludge performance. It was found that the sludge performance of settling property, flocculation and microbial activity increased with increasing concentration of PAM. However, high level of PAM (1 mg/L) led to the formation of large amounts of loose-structure flocs, which eliminated dissolved oxygen transfer and caused the sludge disintegration, resulting in bad settleability and lower microbial activity. In this way, when the dosage of PAM was 0.1 mg/L, the sludge had the best settling property and activity.

  6. Primary visual cortex activity along the apparent-motion trace reflects illusory perception.

    Lars Muckli

    2005-08-01

    Full Text Available The illusion of apparent motion can be induced when visual stimuli are successively presented at different locations. It has been shown in previous studies that motion-sensitive regions in extrastriate cortex are relevant for the processing of apparent motion, but it is unclear whether primary visual cortex (V1 is also involved in the representation of the illusory motion path. We investigated, in human subjects, apparent-motion-related activity in patches of V1 representing locations along the path of illusory stimulus motion using functional magnetic resonance imaging. Here we show that apparent motion caused a blood-oxygenation-level-dependent response along the V1 representations of the apparent-motion path, including regions that were not directly activated by the apparent-motion-inducing stimuli. This response was unaltered when participants had to perform an attention-demanding task that diverted their attention away from the stimulus. With a bistable motion quartet, we confirmed that the activity was related to the conscious perception of movement. Our data suggest that V1 is part of the network that represents the illusory path of apparent motion. The activation in V1 can be explained either by lateral interactions within V1 or by feedback mechanisms from higher visual areas, especially the motion-sensitive human MT/V5 complex.

  7. Effect of trace amounts of polyacrylamide (PAM) on long-term performance of activated sludge.

    Luo, Yuan-ling; Yang, Zhao-hui; Xu, Zheng-yong; Zhou, Ling-jun; Zeng, Guang-ming; Huang, Jing; Xiao, Yong; Wang, Li-ke

    2011-05-15

    This study aims at evaluating the impacts of PAM addition on activated sludge performance. Four lab-scale sequencing batch reactors (SBRs), each with a working volume of 3L, were investigated with different PAM concentrations. Experiments were conducted with varying organic loading rate and the sludge volume index (SVI), particle size, zeta potential, specific oxygen uptake rate (SOUR), mixed liquor suspended solids (MLSS), COD and ammonium removal efficiency were monitored over a 105-day period. The results showed that all of the PAM addition not only improved the removal efficiencies of COD and ammonium, but also exhibited some advantages on sludge performance. It was found that the sludge performance of settling property, flocculation and microbial activity increased with increasing concentration of PAM. However, high level of PAM (1mg/L) led to the formation of large amounts of loose-structure flocs, which eliminated dissolved oxygen transfer and caused the sludge disintegration, resulting in bad settleability and lower microbial activity. In this way, when the dosage of PAM was 0.1mg/L, the sludge had the best settling property and activity. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  8. Neutron activation analysis of trace metallic elements eluted from molecular sieves in the dehydration process of safflower oil

    Takasago, Masahisa; Kobayashi, Koichi; Taru, Yasunori; Takaoka, Kyo (Musashi Inst. of Tech., Tokyo (Japan))

    1992-11-01

    Dissolved water in safflower oil affects the autoxidation of this oil significantly. Molecular sieves were used to remove the dissolved water from the oil. This method is much simpler than that of distillation, and dissolved water can be removed to the same extent as that by distillation. But, due to the elution of many kinds of trace metallic elements in the oil dehydrated with molecular sieves, these elements were analyzed by neutron activation analysis. For a data comparison trace amounts of metallic elements in the oil dehydrated by distillation were also analyzed. Since the intensity of the [gamma] ray-photoelectric peak of nuclide [sup 28]Al was largest among the detected elements, this element was analyzed quantitatively and the other elements qualitatively. In safflower oil dehydrated with molecular sieves, 14 kinds of the elements (I, Br, Al, Mg, Si, V, Cl, Nd, Ta, Cr, Sb, Cs, Co, Na) were detected. Also, I, Br, Cl, Cr, Ta, Sb, and Al elements were detected in the oil dehydrated by distillation. The intensity of the photoelectric peak of nuclide except [sup 28]Al was essentially the same as that in the oil dehydrated by distillation, but the intensity of [sup 28]Al in the oil with molecular sieves was about 28 times stronger than that in distillation oil. In the molecular sieves, 19 impure elements in addition to the original constituents (Na, K, Al, si, O) were detected. It was Al, Na, Si, Nd, Cs, and Co along with impure elements may possibly have been eluted in the oil. Al element in safflower oil dehydrated with molecular sieves was analyzed quantitatively. 0.91 ppm of Al was detected in safflower oil. The eluted amount of Al in safflower oil dehydrated by distillation was 0.032 ppm. A larger amount of Al element was thus eluted into the oil dehydrated with molecular sieves than by distillation. (author).

  9. Neutron activation analysis of trace metallic elements eluted from molecular sieves in the dehydration process of safflower oil

    Takasago, Masahisa; Kobayashi, Koichi; Taru, Yasunori; Takaoka, Kyo

    1992-01-01

    Dissolved water in safflower oil affects the autoxidation of this oil significantly. Molecular sieves were used to remove the dissolved water from the oil. This method is much simpler than that of distillation, and dissolved water can be removed to the same extent as that by distillation. But, due to the elution of many kinds of trace metallic elements in the oil dehydrated with molecular sieves, these elements were analyzed by neutron activation analysis. For a data comparison trace amounts of metallic elements in the oil dehydrated by distillation were also analyzed. Since the intensity of the γ ray-photoelectric peak of nuclide 28 Al was largest among the detected elements, this element was analyzed quantitatively and the other elements qualitatively. In safflower oil dehydrated with molecular sieves, 14 kinds of the elements (I, Br, Al, Mg, Si, V, Cl, Nd, Ta, Cr, Sb, Cs, Co, Na) were detected. Also, I, Br, Cl, Cr, Ta, Sb, and Al elements were detected in the oil dehydrated by distillation. The intensity of the photoelectric peak of nuclide except 28 Al was essentially the same as that in the oil dehydrated by distillation, but the intensity of 28 Al in the oil with molecular sieves was about 28 times stronger than that in distillation oil. In the molecular sieves, 19 impure elements in addition to the original constituents (Na, K, Al, si, O) were detected. It was Al, Na, Si, Nd, Cs, and Co along with impure elements may possibly have been eluted in the oil. Al element in safflower oil dehydrated with molecular sieves was analyzed quantitatively. 0.91 ppm of Al was detected in safflower oil. The eluted amount of Al in safflower oil dehydrated by distillation was 0.032 ppm. A larger amount of Al element was thus eluted into the oil dehydrated with molecular sieves than by distillation. (author)

  10. Trace analysis

    Warner, M.

    1987-01-01

    What is the current state of quantitative trace analytical chemistry? What are today's research efforts? And what challenges does the future hold? These are some of the questions addressed at a recent four-day symposium sponsored by the National Bureau of Standards (NBS) entitled Accuracy in Trace Analysis - Accomplishments, Goals, Challenges. The two plenary sessions held on the first day of the symposium reviewed the history of quantitative trace analysis, discussed the present situation from academic and industrial perspectives, and summarized future needs. The remaining three days of the symposium consisted of parallel sessions dealing with the measurement process; quantitation in materials; environmental, clinical, and nutrient analysis; and advances in analytical techniques

  11. Survey of trace elements in coals and coal-related materials by neutron activation analysis

    Ruch, R.R.; Cahill, R.A.; Frost, J.K.; Camp, L.R.; Gluskoter, H.J.

    1977-01-01

    Utilizing primarily instrumental neutron activation analysis and other analytical methods such as neutron-activation analysis with radiochemical separation, emission spectrochemical analysis, atomic absorption spectroscopy, X-ray fluorescence analysis, ion-selective electrode analysis, and American Society for Testing of Materials procedures (ASTM), as many as 61 elements were quantitatively surveyed in 170 U.S. whole coals, 70 washed coals, and 40 bench samples. Data on areal and vertical distributions in various regions were obtained along with extensive information on the mode of occurence of various elements in the coal matrix itself. Efforts have been made to attain the maximal accuracy and precision possible for a wide variety of elements in the inhomogeneous coal matrix. (T.G.)

  12. Determination of trace elements in seawater by neutron activation analysis and electrochemical separation

    Jorstad, K.; Salbu, B.

    1980-01-01

    The combination of neutron activation analysis and electrolysis at a constant, controlled potential has proved itself to be a useful multielement method for the determination of 28 elements in seawater. After freeze-drying and irradiation, the samples are dissolved and electrolyzed for 1 h. The radioactive species deposited on the mercury cathode allow determination of 14 elements (Ag, As, Au, Cd, Co, Cr, Fe, Ga, Hg, La, Mo, Sb, Se, Zn). Another 14 elements (Ba, Br, Ca, Ce, Cs, Eu, Na, Rb, Sc, Sm, Sr, Th, U, Yb) are quantitatively determined by measuring the activities in the residual solution. To obtain a reproducible electrolysis, radioactive tracers have been used to study the decrease of element concentrations in solution as a function of time of electrolysis, the influence of the initial element concentration on the rate constant k, the effect of cathode material and of the pH in the solution. 4 figures, 4 tables

  13. Identification of Se trace element in the soybean using neutron activation analysis

    Sihombing, E.; Sri Wardani; Hamzah, A.

    1999-01-01

    Neutron Activation Analysis method has been developed as a fast analysis method with high sensitivity, accuracy and precision in determining distribution of element content of various types of seed food materials. In this research the element content of Se was determined by irradiating sample of black and white soybean that can be bought in the market. For determining the content of long decay time element of Se, a samples of 1.3 - 2.3 grams of seed was irradiated within 45 minutes where as for short decay time of Se, the 1,2 - 2,2 grams of seed was irradiated within 30 minutes in the reactor wall. The activated sample, then, was analyzed using gamma spectrometry method. The gamma spectrum was acquired with Hp Ge detector with counting time within 2 - 60 minutes. The results showed that there is a small deviation on Se's quantity of contents with vary between 154,2 and 165,8 ppb

  14. Determination of trace elements in metallic materials by neutron activation analysis

    Grassi, B; La Vecchia, G M; Manera, S; Salvini, A; Zenoni, A

    2006-01-01

    The aim of the present paper is to verify the applicability of neutron activation analysis to a metallurgic problem as a possible alternative technique to the standard investigation methodologies. A first series of measurements was performed in order to check the feasibility of irradiation and counting over metallic samples. Some of the feared problems concerned an excessive activation of the matrix and the consequent difficulties in the spectrum interpretation, as well as the removal of the radioactive waste created by the irradiation. Afterwards, a second series of measurements was performed to collect results aimed at the solution of a specific metallurgic case. The tests were performed at the TRIGA MARK II reactor facility of the LENA (Laboratorio Energia Nucleare Applicata) Institute of the Pavia University

  15. Ebola virus disease contact tracing activities, lessons learned and best practices during the Duport Road outbreak in Monrovia, Liberia, November 2015.

    Caitlin M Wolfe

    2017-06-01

    Full Text Available Contact tracing is one of the key response activities necessary for halting Ebola Virus Disease (EVD transmission. Key elements of contact tracing include identification of persons who have been in contact with confirmed EVD cases and careful monitoring for EVD symptoms, but the details of implementation likely influence their effectiveness. In November 2015, several months after a major Ebola outbreak was controlled in Liberia, three members of a family were confirmed positive for EVD in the Duport Road area of Monrovia. The cluster provided an opportunity to implement and evaluate modified approaches to contact tracing.The approaches employed for improved contact tracing included classification and risk-based management of identified contacts (including facility based isolation of some high risk contacts, provision of support to persons being monitored, and school-based surveillance for some persons with potential exposure but not listed as contacts, use of phone records to help locate missing contacts, and modifications to data management tools. We recorded details about the implementation of these approaches, report the overall outcomes of the contact tracing efforts and the challenges encountered, and provide recommendations for management of future outbreaks.165 contacts were identified (with over 150 identified within 48 hours of confirmation of the EVD cases and all initially missing contacts were located. Contacts were closely monitored and promptly tested if symptomatic; no contacts developed disease. Encountered challenges related to knowledge gaps among contact tracing staff, data management, and coordination of contact tracing activities with efforts to offer Ebola vaccine.The Duport Road EVD cluster was promptly controlled. Missing contacts were effectively identified, and identified contacts were effectively monitored and rapidly tested. There is a persistent risk of EVD reemergence in Liberia; the experience controlling each

  16. Ebola virus disease contact tracing activities, lessons learned and best practices during the Duport Road outbreak in Monrovia, Liberia, November 2015.

    Wolfe, Caitlin M; Hamblion, Esther L; Schulte, Jacqueline; Williams, Parker; Koryon, Augustine; Enders, Jonathan; Sanor, Varlee; Wapoe, Yatta; Kwayon, Dash; Blackley, David J; Laney, Anthony S; Weston, Emily J; Dokubo, Emily K; Davies-Wayne, Gloria; Wendland, Annika; Daw, Valerie T S; Badini, Mehboob; Clement, Peter; Mahmoud, Nuha; Williams, Desmond; Gasasira, Alex; Nyenswah, Tolbert G; Fallah, Mosoka

    2017-06-01

    Contact tracing is one of the key response activities necessary for halting Ebola Virus Disease (EVD) transmission. Key elements of contact tracing include identification of persons who have been in contact with confirmed EVD cases and careful monitoring for EVD symptoms, but the details of implementation likely influence their effectiveness. In November 2015, several months after a major Ebola outbreak was controlled in Liberia, three members of a family were confirmed positive for EVD in the Duport Road area of Monrovia. The cluster provided an opportunity to implement and evaluate modified approaches to contact tracing. The approaches employed for improved contact tracing included classification and risk-based management of identified contacts (including facility based isolation of some high risk contacts, provision of support to persons being monitored, and school-based surveillance for some persons with potential exposure but not listed as contacts), use of phone records to help locate missing contacts, and modifications to data management tools. We recorded details about the implementation of these approaches, report the overall outcomes of the contact tracing efforts and the challenges encountered, and provide recommendations for management of future outbreaks. 165 contacts were identified (with over 150 identified within 48 hours of confirmation of the EVD cases) and all initially missing contacts were located. Contacts were closely monitored and promptly tested if symptomatic; no contacts developed disease. Encountered challenges related to knowledge gaps among contact tracing staff, data management, and coordination of contact tracing activities with efforts to offer Ebola vaccine. The Duport Road EVD cluster was promptly controlled. Missing contacts were effectively identified, and identified contacts were effectively monitored and rapidly tested. There is a persistent risk of EVD reemergence in Liberia; the experience controlling each cluster can help

  17. Neutron activation analysis of selected trace elements in benign diseases of the thyroid

    Baldauf, K.; Schicke, B.; Wiesener, W.

    Neutron activation analyses of I, Mn, Zn and Cu were performed in the hair of euthyroid women and female patients suffering from diffuse-nodular goiter and hyperthyroidism, resp. Because of the significant differences in Zn, I and Mn content between euthyroid and hyperthyroid patients, the separation point and the coefficient of valadity were determined. While the analysis of Zn and I in hyperthyroidism is decisive concerning the differential diagnosis, for Mn a tentative diagnosis can be ensured, only

  18. Distribution of natural radioactive and trace elements in the soils and sands from the high radiation coastal belt of India

    Kulkarni, V.V.; Pillai, T.N.V.; Ganguly, A.K.

    1974-01-01

    A brief introduction of the work, already done in connection with the radioactivity present in soils in India, is given. Thorium daughter product activity is estimated in samples collected from monazite area, using gamma spectrometry. The activity is estimated quantitatively and the external dose as well as the genetically significant dose are calculated. Labile components in field soils and beach sands are estimated and the elements are analysed. The experimental procedure adopted is also described. The physico-chemical investigations carried out are explained with reference to the base exchange capacity, loss on ignition, particle size analysis, etc. The results have been presented in the form of tables and they are discussed in detail. (K.B.)

  19. Relationship of in-coming radiation with photosynthetically active, infra-red and net radiations in Brassica species and rocket salad (Eruca sativa)

    Nandwal, A.S.; Kuhad, M.S.

    1989-01-01

    Marked variation was observed among genotypes when the data for in-coming solar radiation were monitored horizontally. The regression equation for in-coming solar radiation versus photosynthetically active radiation and incoming solar radiation versus in-coming infra red radiation indicated linear relationship

  20. Active Moss Biomonitoring of Atmospheric Trace Element Deposition in Belgrade Urban Area using ENAA and AAS

    Anicic, M.; Tasic, M.; Tomasevic, M.; Rajsic, S.; Frontasyeva, M. V.; Strelkova, L. P.; Steinnes, E.

    2007-01-01

    Active biomonitoring of air quality in Belgrade, Serbia, was performed using the moss Sphagnum girgensohnii. Moss bags were exposed in parallel with and without irrigation respectively for four consecutive 3-month periods at three urban sites. Twenty-nine elements were determined in the exposed moss samples by ENAA and three (Cu, Cd, and Pb) by AAS. The relative accumulation factor (RAF) was greater than 1 for the majority of elements. Elements such as Cl, K, Rb and Cs, however, leached from the moss tissue during the exposure time. For all exposure periods, higher uptake in the irrigated moss bags was evident for Al, Cr, Fe, Cu, Zn, Sr, Pb, and Cd

  1. Determination of trace elements in cardiotonic drugs by neutron activation analysis

    Kanias, G.D.

    1980-01-01

    Potassium may be intimately involved in the action of cardiac glycosides. Chlorine and potassium also act as diuretics. The elements chlorine, manganese, potassium and sodium are determined by instrumental neutron activation analysis in the cardiotonic drugs (pills, injections, water solutions). It has been found that there is a wide variation among the different values for manganese, sodium and chlorine while for potassium values are relatively constant. Results are discussed from the pharmacological point of view. It is proposed to study the role of manganese in cardiotonic drugs as well as the effect of potassium addition in oral pharmaceutical form of cardiotonic drugs in decreasing the toxicity of cardiac glycosides. (author)

  2. Trace element determination in human bones using the neutron activation analysis method

    Kramarski, Sila; Saiki, Mitiko; Borelli, Aurelio; Batalha, Joao R.F.

    1997-01-01

    This work presents the results obtained in the analysis of rib bone samples from normal human individuals by applying instrumental neutron activation analysis. In these analyses, the elements Br, Cl, Fe, K, Mg, Na, Rb, Sr and Zn were found at the ppm level and the elements Ca and P at the level of percentage. The precision and the of the results were evaluated by using biological reference materials NIST SRM 1577a Bovine Liver, IAEA A-11 Milk powder, NIES CRM 9 Sargasso e NIES CRM 10A Rice Flour Unpolished. (author). 5 refs., 3 tabs

  3. Radiation

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  4. Trace elements in California aerosols. Part I. Instrumental neutron activation analysis techniques

    Ragaini, R.C.; Ralston, H.R.; Garvis, D.; Kaifer, R.

    1975-01-01

    Instrumental Neutron Activation Analysis (INAA) done at LLL played a key role in the 1972--1974 California Aerosol Characterization Experiment (ACHEX), a major experiment in the chemistry of aerosols in urban and non-urban sites of California sponsored by the State of California Air Resources Board. The main purpose of INAA was to measure the particle size distributions and diurnal patterns of key chemical constituents in aerosols collected in California. These data were used to satisfy some of the key objectives of ACHEX, including aerosol characterization and evaluation of the origins and evolutions of aerosols. Secondary uses of INAA were the validations of the Lundgren rotating drum cascade impactors used in the ACHEX, and validations of other analytical techniques used in the chemical analyses. As a result of these studies, it was concluded that techniques using INAA were useful operational methods for chemical analysis of aerosols collected over two-hour periods in urban air with an active monitoring program. (U.S.)

  5. Determination of traces of lithium in biological, environmental and metal samples by neutron activation analysis

    Yang, J.Y.; Tseng, C.L.; Lo, J.M.; Yang, M.H.

    1985-01-01

    Lithium in environmental, biological and metal samples was determined by neutron activation analysis via the 6 Li(n,α)T and 16 O(T,n) 18 F reactions. The samples were converted to aqueous solutions either by dissolution or by digestion and their aliquots were irradiated in a nuclear reactor for 2 h. The irradiated sample solution, was placed in a ZrO 2 column on which the 18 F nuclide was adsorbed. Most of the coexisting nuclides 24 Na, 82 Br, 38 Cl, 64 Cu, etc. were separated by elution with pH 1proportional3 solution. The column was subjected to a Ge(Li) detector for γ-ray spectrometry. The lithium content in the sample was estimated from the 18 F activity obtained. The matrix effect can be eliminated by either strong dilution of the samples in aqueous medium or by the method of standard addition. Lithium can be determined with high precision and accuracy in sub-ppm samples. (orig.) [de

  6. Determination of trace elements in some Nigerian vegetable based oils by neutron activation analysis

    Obi, A.L.; Jonah, S.A.; Umar, I.

    2001-01-01

    The concentrations of some essential micronutrient elements leading to short-lived activation products in four Nigerian vegetable based oils (palm oil, palm kernel oil, sheabutter and groundnut oil) have been determined by neutron activation analysis using a small research reactor. One sample of each material was analysed and presented as an introduction for further investigations. Results indicate that the concentration range of the elements are 19.4-44.0 μg/g for Al; 30.0-81.0 μg/g for Ca; 11.9-60.4 μg/g for Cl; 1.43-5.96 μg/g for Cu; 7.3-28.1 μg/g for Mg; 0.47-1.69 μg/g for Mn; 17.5-72.8 μg/g for Na and 0.04-0.07 μg/g for V. The experimental procedure is suitable for routine determination of micronutrient element in foods for control and monitoring purposes. (author)

  7. The study of the trace element in organisms by neutron activation analysis, 1

    Shinogi, Masaki; Murai, Yasuko; Mori, Itsuhiko; Takeuchi, Takayuki.

    1974-01-01

    Examinations were made on optimal experimental conditions for instrumental determination of various elements in cannabis by neutron activation analysis, without any radiochemical separation, and the following conditions were found to be useful. Irradiation samples to be used are about 300 mg of the leaves or stem bark, and about 100 mg of the root. For soil sample, about 50 mg is used for the determination of short half-life nuclides and about 300 mg for long half-life nuclides. For short half-life nuclides, the samples are irradiated for 1 min, activity is measured for 200 sec after a decay of 3 min, and for 400 sec after a decay of 10 min. For long half-life nuclides, the samples are irradiated for 60 min and the activites are measured for 4 K sec after 1 week and for 10 K sec after 1 month. Use of supersonic waves is also convenient for cleansing of the samples. Thirty-five kinds of interesting elements were determined by this method from cannabis cultivated in Maizuru area. (auth.)

  8. Active living and biking: tracing the evolution of a biking system in Arlington, Virginia.

    Hanson, Royce; Young, Garry

    2008-06-01

    In Arlington, Virginia, a steady evolutionary change in biking policy during the last three decades has yielded some of the nation's best biking assets. It has a comprehensive, well-connected, highly integrated, well-mapped, and well-signed system of shared-use paved trails, bike lanes, bike routes, and other biking assets, such as workplace showers. Understanding the conditions that led to Arlington's current biking system can provide lessons in the strategy and tactics of active-living politics. One potentially effective political strategy that was successful in Arlington is for activists to pressure elected officials to select professional managers who see bike-ways as crucial to the overall transportation system. Then it is important to formalize the government-citizen relationship through an advisory panel. Also, in Arlington, the incremental creation of biking assets helped create demand for more and better facilities. In turn, this created political support for expanding and upgrading. Finally, Arlington used potentially negative circumstances (e.g., the building of highway corridors, the introduction of the Metro) as opportunities to change the built environment in ways that have encouraged more active living.

  9. Influence of trace elements on the activity of some microbiological processes in soil

    Maliszewska, W

    1972-01-01

    It was found that N fixation was stimulated by B, Zn, Mo and Co. Fe and Cu had an evident inhibiting and Cd even toxic influence on this process. Zn and Fe stimulated proteolase activity. Mo showed almost no effect on that process. The other microelements used had a more or less inhibiting influence. Ammonification was affected with B and Mo. The other treatments had different hampering effects on that process. The nitrifyers were mostly stimulated by Fe and Al. The other microelements B, Zn, Mo and Mn, stimulated the development of nitifyers, but to a lesser degree. Cu and Cd were toxic. The highest intensity of denitrification was found without any microelement addition. The most distinct inhibition of the process was caused by Cu, Zn, and Co. Hemicellulose decomposition activity was very sensitive to a deficiency of microelements investigated. Only Zn and Mo inhibited this process. In general Cu and Cd showed the most inhibiting effect on all the biological processes investigated in the experiments. The highest stimulatory effect in all experiments was caused by B and Mo. 5 references, 4 figures, 1 table.

  10. Trace Elements Distribution in Human Gallstones, Bile and Gallbladder Tissues Using Instrumental Neutron Activation Analysis

    Abugassa, I. O.; Khrbish, Y. S.; Bshir, A. T.; Doubali, K.; Abugassa, S. O.

    2007-01-01

    This study focuses on the elemental distribution in different types of gallstones; bile and gallbladder tissues using neutron activation analysis technique based on k0-INAA method in Tajura center. Samples were collected from patients who undergone open surgery of gallbladder (cholecystectomy) at El-khadra University Hospital in Tripoli, aged between 23-80 yr. The samples obtained from patients who don't suffer from any chronic diseases, therefore, they were not taking any medications that might elevate the concentration of certain elements in the body. Samples were prepared and lyophilized by different process in a clean room. All samples were irradiated in the reactor and measured in the neutron activation laboratory. In order to obtain accurate results, Au and Zr flux monitors were irradiated with the samples for flux ratio (f) and α determinations and to account for any flux variations within the container. The irradiations of the samples were carried out in the reactor channels VCR11 and VCR12 for 8 hours under f (32 and 14) and α parameters (0.0183, 0.1678) respectively. More than 20 elements were determined in the above mentioned samples. Several SRM were irradiated with the samples to insure the reliability of the results.

  11. Metal and trace element sediment assessment from Salto Grande reservoir, Sao Paulo state, Brazil, by instrumental neutron activation analysis

    Soares, Walace A.A., E-mail: walace@usp.br [Setor de Analises Toxicologicas. CETESB, Sao Paulo, SP (Brazil); Favaro, Deborah I.T., E-mail: defavaro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Lab. de Analise por Ativacao com Neutrons

    2011-07-01

    The Salto Grande Reservoir is used for electric generation, irrigation, fish farming, recreation and water supply for the region's cities. The reservoir belongs to the city of Americana, located in on the eastern region of Sao Paulo State, Brazil. It belongs to the Piracicaba River Hydrographic Basin, the second most important economic and populated region and one of the most polluted areas in the State. This basin is located in a highly industrialized and agricultural region. Due to urban, industrial and agricultural activities as well as sewage wastes the water and sediments of this reservoir and surroundings are extremely contaminated, mainly by metals, according to CETESB (Environmental Control Agency of the Sao Paulo State). In order to obtain better information about its sediment contamination the present study reports results of the concentration of some major (Ca, Fe, K and Na), trace (As, Ba, Br, Co, Cr, Cs, Hf, Rb, Sb, Se, Ta, Th, U, Zn and rare earth (Ce, Eu, La, Lu, Nd, Sc, Sm, Tb and Yb)) elements in sediments and Cd, Cr, Cu, Ni and Pb concentration in sediments and water from the Salto Grande Reservoir. Multielementar analysis was carried out by Instrumental Neutron Activation Analysis (INAA). Multielemental concentrations in the sediment samples were compared to NASC (North American Shale Composite) values. The concentration values for metals As, Cd, Cr, Cu, Pb, Ni and Zn were compared to the Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL) and adopted by CETESB, (author)

  12. Main and trace element analysis of urinary stones by means of neutron activation and X-ray fluorescence

    Buehling, A.; Riotte, H.G.

    1978-01-01

    Metallosis, a tissue reaction to metal implants which is caused by corrosion of the implanted metal caused by body liquids, makes activation analysis interesting as a method to determine trace element distributions in tissue and organs. Osteosynthesis of the eft hind leg was carried out in 30 rabbits. The bone fragments were fixated with V4A steel plates and 3-4 screws each. One xear after implantation a total of 350 samples was taken in contact tissue, muscles, lymphatic tissue, kidneys, liver, lungs, and heart and investigated by instrumental neutron activation analysis. The elements Na, K, Cr, Fe, Co, Ni, Zn, Se, Rb, Mo, Cs, Ta, and W were quantitatively determinde. Four animals of the same strain hald under the same condition were used as controls. It was found that the alloy components of the V4A steel implants burden the body even at considerable distance. Of particular interest are the findings for lympatic tissue, liver and kidneys, which indicate tendencies of Cr and Ni accumulation. Element correlations showed that the tissues take up the metal ions in nearly constant ratios, with the exception of iron. The concentrations of other essential elements like Zn, Se, Rb, and k are also influenced by the implants. (orig.) [de

  13. Silver nanoparticle accumulation by aquatic organisms – neutron activation as a tool for the environmental fate of nanoparticles tracing

    Asztemborska Monika

    2014-12-01

    Full Text Available Water environments are noted as being some of the most exposed to the influence of toxic nanoparticles (NPs. Therefore, there is a growing need for the investigation of the accumulation and toxicity of NPs to aquatic organisms. In our studies neutron activation followed by gamma spectrometry and liquid scintillation counting were used for studying the accumulation of silver nanoparticles (AgNPs by freshwater larvae of Chironomus and fish Danio rerio. The influence of exposition time, concentration and the source of nanoparticles on the efficiency of AgNP accumulation were studied. It was found that AgNPs are efficiently accumulated by Chironomid larvae for the first 30 hours of exposition; then, the amount of silver nanoparticles decreases. The silver content in larvae increases together with the NP concentration in water. Larvae which have accumulated AgNPs can be a source of nanoparticles for fish and certainly higher levels of Ag in the trophic chain. In comparison with water contamination, silver nanoparticles are more efficiently accumulated if fish are fed with AgNP-contaminated food. Finally, it was concluded that the applied study strategy, including neutron activation of nanoparticles, is very useful technique for tracing the uptake and accumulation of NPs in organisms

  14. Metal and trace element sediment assessment from Salto Grande reservoir, Sao Paulo state, Brazil, by instrumental neutron activation analysis

    Soares, Walace A.A.; Favaro, Deborah I.T.

    2011-01-01

    The Salto Grande Reservoir is used for electric generation, irrigation, fish farming, recreation and water supply for the region's cities. The reservoir belongs to the city of Americana, located in on the eastern region of Sao Paulo State, Brazil. It belongs to the Piracicaba River Hydrographic Basin, the second most important economic and populated region and one of the most polluted areas in the State. This basin is located in a highly industrialized and agricultural region. Due to urban, industrial and agricultural activities as well as sewage wastes the water and sediments of this reservoir and surroundings are extremely contaminated, mainly by metals, according to CETESB (Environmental Control Agency of the Sao Paulo State). In order to obtain better information about its sediment contamination the present study reports results of the concentration of some major (Ca, Fe, K and Na), trace (As, Ba, Br, Co, Cr, Cs, Hf, Rb, Sb, Se, Ta, Th, U, Zn and rare earth (Ce, Eu, La, Lu, Nd, Sc, Sm, Tb and Yb)) elements in sediments and Cd, Cr, Cu, Ni and Pb concentration in sediments and water from the Salto Grande Reservoir. Multielementar analysis was carried out by Instrumental Neutron Activation Analysis (INAA). Multielemental concentrations in the sediment samples were compared to NASC (North American Shale Composite) values. The concentration values for metals As, Cd, Cr, Cu, Pb, Ni and Zn were compared to the Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL) and adopted by CETESB, (author)

  15. Trace determination of uranium and thorium in biological samples by radiochemical neutron activation analysis

    Benedik, Ljudmila; Repinc, Urska; Byrne, Anthony R.; Stegnar, Peter

    2002-01-01

    Radiochemical neutron activation analysis (RNAA) is an excellent method for determining uranium and thorium; it offers unique possibilities for their ultratrace analysis using selective radiochemical separations. Regarding the favourably sensitive nuclear characteristics of uranium and of thorium with respect to RNAA, but the different half-lives of their induced nuclides, two different approaches were used. In the first approach uranium and thorium were determined separately via 239 U, 239 Np and 233 Pa. In the second approach these elements were 239 239 233 determined simultaneously in a single sample using U and/or Np and Pa. Isolation of induced nuclides was based on separation by extraction and/or anion exchange chromatography. Chemical yields were measured in each sample aliquot using added 235 U, 238 Np and 231 Pa radioisotopic tracers. (author)

  16. Use of activation analysis in determination of metal trace amounts in water

    Nasrala, A. de P.

    1982-01-01

    The viability of the association of the methods of concentration in resins - developed by the 'Fundacao Centro Tecnologico de Minas Gerais' - CETEC - with neutron activation is studied. Besides the study of the resin behaviour under neutron irradiation, studies on the variation of the retention rate in function of ph and of the duration of contact of the solution with the resin are carried on. The element to which greater emphasis in given is mercury, whose analysis presents generally serious difficulties. To support the analyses, two automatic methods for gamma spectra analysis, now in operation, were studied and established. In the experimental conditions employed, the detection limits were: 0.5 ppb for cobalt and 1 ppb for mercury. (I.C.R.) [pt

  17. Trace elements in Turkish tea leaves determined by instrumental neutron activation analysis

    Demiralp, R.

    1985-01-01

    The concentrations of the elements As, Sb, Zn, Co, which are closely related to human health and disorder, was determined by means of INAA in seven of the most commonly used brands of tea. Samples and standards were irradiated 10 min and 2 hrs at pneumatic system and central thimble in the TRIGA MARK-11 research reactor. After irradiation the activities were measured with a coaxial Ge detector coupled to a spectroscopic amplifier. A Cambera 90 model multichannel analyser with an 8K memory was used for pulse hight analysis. The system has a resolution of 2,0 KeV for 1332,5 KeV gamma ray of 60 Co with peak to Compton ratio of 43:1 and efficiency of 18 relative to the 3'' x 3'' NaI(Tl) crystal. Results of the study were presented

  18. Trace impurities analysis determined by neutron activation in the PbI 2 crystal semiconductor

    Hamada, M. M.; Oliveira, I. B.; Armelin, M. J.; Mesquita, C. H.

    2003-06-01

    In this work, a methodology for impurity analysis of PbI 2 was studied to investigate the effectiveness of the purification. Commercial salts were purified by the multi passes zone refining and grown by the Bridgman method. To evaluate the purification efficiency, samples from the bottom, middle and upper sections of the ZR ingot were analyzed after 200, 300 and 500 purification passes, by measurements of the impurity concentrations, using the neutron activation analysis (NAA) technique. There was a significant reduction of the impurities according to the purification numbers. The reduction efficiency was different for each element, namely: Au>Mn>Co˜Ag>K˜Br. The impurity concentration of the crystals grown after 200, 300 and 500 passes and the PbI 2 starting material were analyzed by NAA and plasma optical emission spectroscopy.

  19. Determination of trace elements in Tillandsia usneoides by neutron activation analysis for environmental biomonitoring

    Figueiredo, A.M.G.; Saiki, M.; Ticianelli, R.B.; Domingos, M.; Alves, E.S.; Markert, B.

    2001-01-01

    Neutron activation analysis was applied to the determination of the elements Al, As, Ba, Br, Cl, Co, Cr, Fe, K, Mg, Mn, Mo, Na, Rb, Sb, Sc, Ti, Th, V, Zn and the rare earths La, Ce, Nd, Sm, Eu, Tb and Yb in the epiphytic bromeliad Tillandsia usneoides. The samples were collected at an unpolluted area and exposed in different sites of the city of Sao Paulo, Brazil, and in a control site outside Sao Paulo. The results obtained showed an accumulation of Al, As, Cr, Fe, Mo, Sb, Ti, V and Zn elements in Tillandsia usneoides exposed in polluted sites, indicating a promising potential of this species as a biomonitor of air pollution in Sao Paulo. (author)

  20. Determination of trace elements in aerosols from the antarctic peninsula by neutron activation analysis

    Loureiro, A.L.M.

    1989-01-01

    In this work the neutron activation method was applied to carry out multielemental analysis in aerosols collected in the Brazilian Station 'Comandante Ferraz', located on King George Island, at the Antarctic Peninsula, during 1986 and 1987. The aerosols were collected on 0.45 μum Millipore-MF filter paper, type HA. The analytical method was based on the simultaneous irradiations of filters and synthetic standards in the IEA-R1 nuclear reactor under a thermal neutron flux of about 10 12 n cm -2 s -1 . The induced radioactivity was measured in a gamma ray spectrometer after suitable cooling times. Samples were irradiated twice, with irradiation times varying from 5 minutes to 24 hours. The elements Na, Al, Cl, K, Ca, Sc, V, Mn, Fe, Zn, Br, Sb, La, Au and Th were determined with concentration levels from ng/m 3 to pg/m 3 [pt

  1. Size spectra for trace elements in urban aerosol particles by instrumental neutron activation analysis

    Ondov, J.M.; Divita, F. Jr.

    1993-01-01

    Size-fractionated aerosol samples collected with micro-orifice impactors at Camden, NJ, a heavily industrialized urban area, and at two sites near Washington, DC, were analyzed for elemental constituents determined instrumentally from short-lived neutron activation products. A least-squares peak-fitting method was used with impactor calibration data to determine log-normal distribution parameters, i.e., mass median aerodynamic diameter (MMAD) and geometric standard deviation (σ g ) for particles bearing S, V, Br, and I. For these elements, MMADs ranged from 0.24 to 0.65 μm; 0.23 to 0.53 μm; 0.22 to 0.61 μm, and 0.20 to 0.48 μm, respectively. (author) 15 refs.; 4 figs.; 2 tabs

  2. Trace element pharmacognostical study on diuretic drugs by neutron activation analysis

    Kanias, G.D.; Loukis, A.; Philianos, S.M.

    1979-01-01

    Some pharmacological properties and especially diuretic action of medicinal plants are attributed to their elemental content. The elements chlorine, manganese, potassium and sodium are determined by instrumental neutron activation analysis in the dry samples of the following drugs: stigmata of Zea mays, leaves of Uva ursi, rhizome of Cynodon dactylon, whole plant of Ceterach officinarum as well as in infusions, decoction of the same drugs and in the water used for these preparations. It has been found that manganese and potassium are transferred partially into prepared solutions. Sodium is not transferred into solutions from any of these drugs while only chlorine is transferred partially into infusion of Zea mays. From these results it is concluded that the diuretic action of the examined drugs should not be attributed exclusively to the presence of their potassium and chlorine content but also to other constituents. (author)

  3. Determination of x mercury trace amounts in selected foodstuffs by neutron activation analysis

    Jiranek, V.; Bludovsky, R.

    1976-01-01

    Neutron activation analysis was used for the analysis of dehydrated milk, flour, coffee, tea and rice. The results were compared with those obtained by the photometric determination of mercury by dithizone. Four types of sample distribution by wet ashing were evaluated with regard to mercury volatilization in sample destruction. The samples were irradiated with thermal neutrons, a carrier was added and the samples were dissolved in the mixture of H 2 SO 4 +HClO 4 +HNO 3 . After dilution mercury was extracted using a substoichiometric amount of dithizone dissolved in chloroform. In the extract the radioactivity of 197 Hg was measured by NaI(Tl). At the average 15% accuracy of determination the lower limit of determination is 0.003 μg Hg. (M.K.)

  4. Determination of trace cadmium and other elements in bone by epithermal neutron activation analysis

    Dowlati, R.; Jervis, R.E.

    1991-01-01

    Epithermal neutron activation analysis (ENAA) was applied to measure quantitatively Cd and other elements in bone samples from control and Cd-fed rats. This method was found to be non-destructive to the bone samples, with no sign of 'radiolytic charring' and was sensitive enough to detect and quantify Cd in bone samples at normal levels for mammals (viz. 0.5-1.0μg/g) and higher. Two different thermal neutron shield materials were utilized, namely cadmium and boron. The boron shield resulted in a 27% improvement in the detection limit of Cd in bone. The accuracy of ENAA for Cd was assessed by intercomparison with electrothermal atomic absorption spectrophotometry (ETAAS), and the results were in fair agreement (±23%) with those from ENAA. (author) 24 refs.; 5 tabs

  5. Measurement of trace cadmium and elements in bone by epithermal neutron activation analysis

    Dowlati, R.; Jervis, R.E.

    1991-01-01

    Epithermal neutron activation analysis (ENAA) was applied to measure quantitatively Cd and other elements in bone samples from control and Cd-fed rats. This method was found to be non-destructive to the bone samples, with no sign of 'radiolytic charring' and was sensitive enough to detect and quantify Cd in bone samples at normal levels for mammals (viz. 0.5-1.0 μg/g) and higher. Two different thermal neutron shield materials were utilized, namely cadmium and boron. The boron shield resulted in a 27% improvement in the detection limit of Cd in bone. The accuracy of ENAA for Cd was assessed by intercomparison with electrothermal atomic absorption spectrophotometry (ETAAS), and the results in fair agreement (±23%) with those from ENAA

  6. Biological activities caused by far-infrared radiation

    Inoué, Shojiro; Kabaya, Morihiro

    1989-09-01

    Contrary to previous presumption, accumulated evidence indicates that far-infrared rays are biologically active. A small ceramic disk that emist far-infrared rays (4 16 μm) has commonly been applied to a local spot or a whole part of the body for exposure. Pioneering attempts to experimentally analyze an effect of acute and chronic radiation of far-infrared rays on living organisms have detected a growth-promoting effect in growing rats, a sleep-modulatory effect in freely behaving rats and an insomiac patient, and a blood circulation-enhancing effect in human skin. Question-paires to 542 users of far-infrared radiator disks embedded in bedelothes revealed that the majority of the users subjectively evaluated an improvement of their health. These effects on living organisms appear to be non-specifically triggered by an exposure to far-infrared rays, which eventually induce an increase in temperature of the body tissues or, more basically, an elevated motility of body fluids due to decrease in size of water clusters.

  7. Current Status of Trace Metal Pollution in Soils Affected by Industrial Activities

    Kabir, Ehsanul; Ray, Sharmila; Kim, Ki-Hyun; Yoon, Hye-On; Jeon, Eui-Chan; Kim, Yoon Shin; Cho, Yong-Sung; Yun, Seong-Taek; Brown, Richard J. C.

    2012-01-01

    There is a growing public concern over the potential accumulation of heavy metals in soil, owing to rapid industrial development. In an effort to describe the status of the pollutions of soil by industrial activities, relevant data sets reported by many studies were surveyed and reviewed. The results of our analysis indicate that soils were polluted most significantly by metals such as lead, zinc, copper, and cadmium. If the dominant species are evaluated by the highest mean concentration observed for different industry types, the results were grouped into Pb, Zn, Ni, Cu, Fe, and As in smelting and metal production industries, Mn and Cd in the textile industry, and Cr in the leather industry. In most cases, metal levels in the studied areas were found to exceed the common regulation guideline levels enforced by many countries. The geoaccumulation index (I geo), calculated to estimate the enrichment of metal concentrations in soil, showed that the level of metal pollution in most surveyed areas is significant, especially for Pb and Cd. It is thus important to keep systematic and continuous monitoring of heavy metals and their derivatives to manage and suppress such pollution. PMID:22645468

  8. Trace determination of thiram using SERS-active hollow sea-urchin gold nanoparticles

    Zhang, Guanghui; Zhang, Chuankun; Ma, Yanan; Wang, Zheng; Wang, Shun; Xu, Chan; Wang, Dashuang

    2017-01-01

    Surface-enhanced Raman scattering (SERS) is greatly structure-dependent on the absorbed nanoparticles. Nanostructures with different novel morphologies show different Raman enhancement factor orders of magnitude. Herein, a unique nanostructure with fruitful SERS-active sites, composed of hollow interiors and thorns which named as hollow sea-urchin gold nanoparticles (HSU-GNPs), was synthesized by using a one-pot galvanic replacement method. And the corresponding morphologies and optical properties were characterized by TEM images and absorption spectra. Importantly, the synthetic parameters of HSU-GNPs were optimized to obtain a superior SERS performance by analyzing the formation mechanism and the SERS spectra of R6G-labeled HSU-GNPs which obtained at different concentrations of AgNO_3. Furthermore, the SERS-based application of HSU-GNPs was performed on the dose-response detection of thiram. The experimental result shows this detection strategy is available for thiram with decent sensitivity and reproducibility, which suggests that it is an excellent candidate for the detection of pesticides.

  9. Study of trace metals in phosphorite by instrumental neutron activation analysis

    Delgado, J.U.

    1984-01-01

    Methods to determine U, Th and other constituent elements in mineral matrices by the instrumental neutron activation analysis (INAA) have been widely developed. The precise knowledge of these constituent elements is very important for the nuclear technology development. This justifies the use of a technique capable to extract information from small samples. The present work aimed the study of the phosphorites deriving from the State of Pernambuco (PE, Brazil). Its uranium concentration corresponds to one of the highest values found in industrial exploration of phosphate rocks. An experimental methodology based on the INAA associated to the cluster technique was developed. Concentrations of 22 different elements present in the ore were determined with less than 10% uncertainty. The results have shown high correlations in behavior between uranium and rare earth metals. However, the inverse was noted in relation to transition metals. These results indicate the applicability of this method to determine concentrations as well as to classify correlated element groups in mineral matrices. (Author) [pt

  10. Metrological role of reactor neutron activation analysis in contemporary inorganic trace analysis

    Tian Weizhi [China Institute of Atomic Energy, Beijing (China)

    2003-03-01

    In this paper, the inherent characteristics of relative instrumental neutron activation analysis (INAA) as a primary ratio method of measurement, the unique functions of parametric INAA as an ideal back-up method of the relative INAA, and the valuable role of INAA in characterization of sampling behavior of individual elements in certified reference materials (CRMs) will be discussed. In the second of this series, traceability and uncertainty of measurement results by k{sub 0}-INAA will be described. The role of k{sub 0}-INAA as a back-up to relative INAA will be discussed. In the final series, minimum sample size, usually 100 mg or larger, is often the only information given in certificates of the existing certified reference materials (CRMs) to describe sampling behavior. This value is not only too large to cope with the quality control (QC) requirements of microanalysis, but also too general to reflect the strong element-specific nature of sampling behavior of solid materials. The need for CRMs with sampling behavior characterized for individual elements is explained, and the unique role INAA can play in this aspect is described. (J.P.N.)

  11. Metrological role of reactor neutron activation analysis in contemporary inorganic trace analysis

    Tian Weizhi

    2003-01-01

    In this paper, the inherent characteristics of relative instrumental neutron activation analysis (INAA) as a primary ratio method of measurement, the unique functions of parametric INAA as an ideal back-up method of the relative INAA, and the valuable role of INAA in characterization of sampling behavior of individual elements in certified reference materials (CRMs) will be discussed. In the second of this series, traceability and uncertainty of measurement results by k 0 -INAA will be described. The role of k 0 -INAA as a back-up to relative INAA will be discussed. In the final series, minimum sample size, usually 100 mg or larger, is often the only information given in certificates of the existing certified reference materials (CRMs) to describe sampling behavior. This value is not only too large to cope with the quality control (QC) requirements of microanalysis, but also too general to reflect the strong element-specific nature of sampling behavior of solid materials. The need for CRMs with sampling behavior characterized for individual elements is explained, and the unique role INAA can play in this aspect is described. (J.P.N.)

  12. Toxic trace element content of local fruits using instrumental neutron activation analysis (INAA)

    Siddique, N.; Ahmed, S.; Rahman, A; Waheed, S.; Chaudhary, M.M.; Qureshi, I.H.

    1997-01-01

    An important route of entry of environmental contaminants into the human system is through food intake. To study the effect of environmental pollution on the food chain, base line levels of toxic element content of commonly available food articles must be established. This study was undertaken to determine the toxic meal content of Pakistani fruits. The techniques of instrumental Neutron Activation Analysis (INAA) and Atomic Absorption Spectrometry (AAS) were employed for this purpose. Fourteen fruits apple, apricot, banana, data guava, kino, mango, melon, orange, peach, pear, plum, pomegranate and watermelon, as well as, the peels of apple and pear have been investigated and the results are discussed in this paper. The results were found to lie within 95 % confidence limit using Student's t test. Hg, As and Sb were detected, using INAA, in pear, pomegranate and water melon in low amounts (ppb levels) but were not detected in orange, plum and melon. Lesser amounts of toxic elements were detected in the peels of pear and high amounts were detected in apple peel as compared to the edible part of the fruit. Cadmium and lead were determined using Graphite Furnace atomic absorption Spectrometry. Cadmium was found to lie in the range of 18-42 ppb, in most fruits, whereas the amount of lead varied between 39-128 ppb. Lead was below detection limit in melon, guava, mango, and peach contained the highest amount of As, Cd, Hg and Pb. (author)

  13. Trace elements determination in silicon and ferrosilicon reference materials by instrumental neutron activation analysis method

    Moreira, Edson Goncalves; Vasconcellos, Marina Beatriz Agostini; Saiki, Mitiko; Iamashita, Celia Omine

    2002-01-01

    The use of certified reference materials, CRM, is of uppermost importance in the rastreability realization of the measurement process. At times, CRM use is restricted by the non existence of a suitable CRM with similarity to the sample in respect to matrix composition or with element levels in different orders of magnitude. IPT Chemical Division launched a project to prepare a metallic silicon CRM, due to the requirements of the industries in this field. To characterize this new CRM, IPEN Nuclear Reactor Center is able to perform instrumental neutron activation analysis, INAA, a very suitable method for silicon matrix samples because they produce basically the short lived radionuclide 3 1 Si under thermal neutrons flux, which after radioactive decay, does not interfere in the determination of other elements. In this paper, it is presented the determination of As, Br, Co, Cr, K, Eu, Fe, La, Mn, Na Nb, Sb, Sm, Sc, Th, Tb, U, V, W and Yb in silicon CRM NBS SRM 57; ferrosilicon CRM IPT 56; IPT 70; NBS SRM 58a; NBS SRM 59a and silicon RM under preparation IPT 132. From the results, the accuracy and the precision of the process were assessed. (author)

  14. Current Status of Trace Metal Pollution in Soils Affected by Industrial Activities

    Ehsanul Kabir

    2012-01-01

    Full Text Available There is a growing public concern over the potential accumulation of heavy metals in soil, owing to rapid industrial development. In an effort to describe the status of the pollutions of soil by industrial activities, relevant data sets reported by many studies were surveyed and reviewed. The results of our analysis indicate that soils were polluted most significantly by metals such as lead, zinc, copper, and cadmium. If the dominant species are evaluated by the highest mean concentration observed for different industry types, the results were grouped into Pb, Zn, Ni, Cu, Fe, and As in smelting and metal production industries, Mn and Cd in the textile industry, and Cr in the leather industry. In most cases, metal levels in the studied areas were found to exceed the common regulation guideline levels enforced by many countries. The geoaccumulation index (Igeo, calculated to estimate the enrichment of metal concentrations in soil, showed that the level of metal pollution in most surveyed areas is significant, especially for Pb and Cd. It is thus important to keep systematic and continuous monitoring of heavy metals and their derivatives to manage and suppress such pollution.

  15. Trace determination of thiram using SERS-active hollow sea-urchin gold nanoparticles

    Zhang, Guanghui; Zhang, Chuankun, E-mail: zhangchk-lx@huat.edu.cn; Ma, Yanan; Wang, Zheng; Wang, Shun; Xu, Chan; Wang, Dashuang [Hubei University of Automotive Technology, School of Science (China)

    2017-04-15

    Surface-enhanced Raman scattering (SERS) is greatly structure-dependent on the absorbed nanoparticles. Nanostructures with different novel morphologies show different Raman enhancement factor orders of magnitude. Herein, a unique nanostructure with fruitful SERS-active sites, composed of hollow interiors and thorns which named as hollow sea-urchin gold nanoparticles (HSU-GNPs), was synthesized by using a one-pot galvanic replacement method. And the corresponding morphologies and optical properties were characterized by TEM images and absorption spectra. Importantly, the synthetic parameters of HSU-GNPs were optimized to obtain a superior SERS performance by analyzing the formation mechanism and the SERS spectra of R6G-labeled HSU-GNPs which obtained at different concentrations of AgNO{sub 3}. Furthermore, the SERS-based application of HSU-GNPs was performed on the dose-response detection of thiram. The experimental result shows this detection strategy is available for thiram with decent sensitivity and reproducibility, which suggests that it is an excellent candidate for the detection of pesticides.

  16. Major and trace elements assessment in sediment samples from Rio Grande Reservoir, by neutron activation analysis

    Franklin, Robson L.; Ferreira, Francisco J.; Favaro, Deborah I.T.; Bevilacqua, Jose Eduardo

    2009-01-01

    The Rio Grande Reservoir, Southeast of the Sao Paulo Metropolitan Area (SPMA) supplies water for four counties (Sao Bernardo do Campo, Sao Caetano do Sul, Santo Andre and Diadema). It has been seriously affected by urban expansion, due to chaotic urban occupation and improper use of the surrounding areas. In this study bottom sediment samples were collected, by using a Van Veen sampler, during the dry and rainy seasons. Four sampling points were defined by using GPS and are located at the mouth of the Rio Grande and Ribeirao Pires Rivers, in the middle of the reservoir and near the catchment point of the water supply. The sediment samples were submitted to instrumental neutron activation analysis (INAA) and the following elements were determined: As, Ba, Br, Co, Cr, Cs, Rb, Sb, Sc, Se, Ta, Th, U e Zn and the rare earth elements Ce, Eu, La, Lu, Nd, Sm, Tb, Yb. Short irradiation was also performed for total Hg determination by NAA using 197 Hg radioisotope. This was possible due to the high Hg concentration levels in these sediments. The methodology validation was carried out by certified reference material analyses. The results obtained for multielemental concentrations in the sediment samples were compared to NASC (North American Shale Composite) values. The concentration values obtained for As and metals Cr, Hg and Zn in the sediment samples were compared to the Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL values) and adopted by CETESB. (author)

  17. Analysis of impurities at trace levels in metallic niobium by instrumental neutron activation analysis

    Favaro, D.I.T.; Vasconcellos, M.B.A.; Santos, C.

    1989-10-01

    The interest in obtaining niobium of high purity has increased due to the recent applications of this material in both vacuum and high temperature technologies and to its potential uses in the aeronautic and aerospacial industries and in the nuclear energy field. In the present work, a procedure of analysis of impurities in the parts per million level, in eletrolitic and non-eletrolitic niobium samples has been established. The method of neutron activation analysis followed by high resolution gamma ray spectrometry has been used. The elements Al, Na, Mn, Cl and In, in ppm level and Y, in the percentage level, were determined after irradiation from 1 to 20 minutes, under a thermal neutron flux of 10 11 n.cm -2 .s -1 at the IEA-Rl reactor of the IPEN-CNEN/SP. The γ-rays from the radioactive products were measured with a Ge(Li) detector coupled to a 4096 channel analyzer. The elements Ta, Cr and W, in the parts per million level, were determined with irradiation of 8 hours under a thermal neutron flux of 10 12 n.cm -2 .s -1 . (autor) [pt

  18. Activities in biological radiation research at the AGF

    1984-01-01

    The AGF is working on a wide spectrum of biological radiation research, with the different scientific disciplines contributing different methodologies to long-term research projects. The following fields are studied: 1. Molecular and cellular modes of action of radiation. 2. Detection and characterisation of biological radiation damage, especially in humans. 3. Medical applications of radiation effects. 4. Concepts and methods of radiation protection. The studies will lead to suggestions for radiation protection and improved radiotherapy. They may also contribute to the development of environmental protection strategies. (orig./MG) [de

  19. Application of neutron activation analysis to the study of the variations of the concentration of trace elements in various organs of rat as a function of age

    Maziere, B.; Loc'h, C.; Stulzaft, O.; Gaudry, A.; Comar, D.

    1976-01-01

    In order to know the normal distribution of trace elements in rats as accurately as possible, the composition of different organs and body tissues by neutron activation analysis was determined in animals from 15 days to 22 months old. The experiment conditions were described. Normal concentrations for more than 20 trace elements were obtained, some of them being less than a tenth of a part per billion. The experiment has shown that variations in elemental concentrations in terms of age were a general phenomenon and that for some elements a steady state is apparently never attained

  20. Changes of trace element concentrations in vegetables during the usual food processing in the household found out by means of activation analysis

    Schelenz, R.

    1981-01-01

    The influence of processing of various vegetables and potatoes (cleaning, cutting, washing, cooking, steam-cooking) on the concentration of ingestion-physiologically important mineral- and trace elements has been studied by means of instrumental activation analysis. The leaching effects play a less important role in steam-cooking. Than in normal cooking. The most important loss already occurs when preparing the vegetables for cooking. This applies especially also to the essential trace elements; but also toxic elements such as arsenic are greatly reduced during this process. (RB) [de

  1. Trace element characteristics of indian cigarette tobacco by instrumental neutron activation analysis

    Garg, A.N.; Vivek Singh; Chutke, N.L.; Ambulkar, M.N.

    1995-01-01

    In order to determine hazardous effects of smoking five different brands of Indian cigarette tobacco including its ash and smoke, three brands of bi di (a typical of Indian subcontinent) and two of chewing tobacco have been analysed for 24 elements (As, Ba, Br, Ca, Ce, Co, Cr, Cs, Cu, Eu, Fe, Hg, K, Hf, La, Na, P, Rb, Sb, Sc, Se, Sr, Th and Zn) by instrumental neutron activation analysis (INAA). A simple and indigenous smoking device has been developed. A mean ash content of 16.5 ± 1.1% was obtained for different brands of cigarettes whereas smoke content was found to be 4.8±0.8%. It is observed that most elements are retained in ash and a few are transferred to smoke. Percent amount of elements retained in ash and transferred to smoke condensate have been calculated. Significant amounts of Sb, Hg, Co, Se and Zn are transferred to smoke but >90% of Ca, Fe, Sr and Cr are retained in ash. a comparison of elemental contents with the cigarette tobacco from other countries shows comparable amounts for most elements except few minor variations attributable to local soil characteristics. Most elemental contents in bi di and chewing tobacco are comparable except Br, Cr, Na, Se and Sr which are higher in chewing tobacco but its Ca content is lower. Standard Reference Materials Bowen's Kale, Kentucky Reference Cigarette and Citrus Leaves (SRM 1572) along with a newly developed tobacco CRM OTL-1 from Poland were also analysed. (author). 31 refs., 1 fig., 4 tabs

  2. Analytic determination of the activation of essential and toxic trace elements in biological material

    Schelenz, R.

    1980-01-01

    A neutron activation-analysis technique for the multielement determination in biological material was developed. The individual steps of this procedure comprise radiochemical and also instrumental analytic techniques. After radiochemical separation 34 elements can be determined, after only instrumental procedures 26 elements can be detected in biological material. The radiochemical analysis of 34 elements lasts 4 days. Tracer investigations on the radionuclide retention of the anorganic separators HAP, TiP and ZP in 9N aqueous HNO 3 solution indicated that apart from Na-24, K-42 and P-32 the radionuclides Cs-134, Rb-86 and Se-75 are almost quantitatively adsorbed at the separators. For the remaining investigated radionuclides different but well-reproducible retention values resulted. The pH-value only slightly influences the extent of the radionuclide retention. Kinetic investigations on the radiochemical precipitation of some radionuclides on Cu and Cu(Hg)sub(x) were carried out. The depositing of the radionuclides Ag-110m, Hg-203 and Se-75 at 0 0 C and room temperature on Cu(Hg)sub(x) and Cu foil is a first order reaction. The half-life periods and the velocity constants of the depositing on Cu and Cu(Hg)sub(x) were determined for the investigated radionuclides in dependency of the temperature. The technique was examined by means of international biological multielement standards of known element combinations. The realisation of ring tests for the multielement determination in potatoe and milk powder showed that this method provides precise results. The applicability of the radiochemical method was confirmed by the simultaneous determination of 25 elements in overall nutrition samples. The instrumental technique was applied for the multielement determination in human hair (of the head) and in river water. (orig./MG) [de

  3. Determination of trace elements in lichen samples by neutron activation analysis

    Saiki, Mitiko; Coccaro, D.M.B.; Vasconcellos, M.B.A.; Marcelli, M.P.

    1999-01-01

    Epiphytic lichens have been used as bioindicators of environmental pollution studies because of their ability to accumulate metals present in the atmosphere at very low concentrations. In this work, experimental conditions for collection and preparation of the lichen samples as well as the experimental procedure for neutron activation analysis were established in order to obtain reliable and useful data for environmental monitoring purposes. Lichen samples were collected from the barks of trees. They were first examined in a stereo microscope, cleaned and then they were washed with water, freeze-dried and ground for analysis. Out of the five species Usnea sp, Parmotrena tinctorum, Canoparmelia caroliniana, Parmotrema sanctiangeli and Canoparmelia texana analysed, the latter was chosen for this work since this species is very abundant on the Brazilian territory except for the coast. The samples and synthetic standards of elements were irradiated at the IEA-R1 nuclear reactor and the concentrations of the elements Al, As, Br, Ca, Cd, Cl, Co, Cr, Cs, Fe, K, lanthanides, Mg, Mn, Na, Rb, Sb, Sc, Se, Th, U, V and Zn were determined by using short and long irradiations. Results obtained in the washed and unwashed lichen samples showed that the cleaning with water can be used in order to eliminate adhering materials. Indeed, most of elements of interest for the environmental contamination accumulated by the lichens were not removed. The study of the influence of the age of the lichen indicated that its elemental concentrations increase with its age or with the length of exposure. Results obtained for lichens collected from four different trees in the same sampling area varied from about 3.4 to 50%. The homogeneity of the sample was checked by analyzing replicates. The precision and the accuracy of the method were evaluated by analyzing IAEA 336 Lichen and NIST 1752 Citrus Leaves. (author)

  4. Determination of trace elements in lichen samples by instrumental neutron activation analysis

    Saiki, Mitiko; Horimoto, Lidia K.; Vasconcellos, Marina B.A.; Marcelli, Marcelo P.; Sumita, Nairo M.; Saldiva, Paulo H.N.

    2001-01-01

    Samples of Canoparmelia texana lichen collected in different sites of Sao Paulo and Parana States, Brazil, were analysed by neutron activation analysis in order to obtain preliminary information on the air quality in these regions and also to select a region of interest for biomonitoring studies. Also Tadescantia pallida plant has been analysed in order to study the viability of using this specimen in environmental pollution monitoring. Lichens samples were collected from tree barks which were also collected to investigate the contribution of substrate derived elements to elements present in lichens. Young and old leaves of T. pallida were collected separately in order to study the leaf age effects on their elemental levels. The samples were cleaned, washed with distilled water, dried and ground for the analyses. Samples and standards were irradiated at the IEA-Rlm nuclear reactor for short and long periods and concentrations of the elements Al, As, Ca, Cd, Cl, Co, Cr, Cs, Fe, Hf, Mg, Mn, Rb, Sb, Sc, D, Th, U, V Zn and lanthanides were determined. Preliminary results obtained for T. texana lichen indicated that three sites (Ibiuna, Botanical Garden and Parque de Vila Velha) present low concentrations of the most elements analysed. Therefore lichens from these regions could be analysed to establish baseline levels of elements for monitoring purposes. Samples collected in open areas presented high concentrations of some elements probably due to the accumulation of elements originating from soil and from heavy vehicular traffic. Elemental concentrations obtained in outer barks were similar or smaller than those results obtained for lichens. Results obtained for T. pallida indicated that concentrations of elements in old leaves of this plant are of the same magnitude or slightly higher than those presented in young ones. (author)

  5. Biogas pre-upgrading by adsorption of trace compounds onto granular activated carbons and an activated carbon fiber-cloth.

    Boulinguiez, B; Le Cloirec, P

    2009-01-01

    The study assesses the adsorption onto activated carbon materials of selected volatile organic compounds -VOCs- (dichloromethane, 2-propanol, toluene, siloxane D4) in a biogas matrix composed of methane and carbon dioxide (55:45 v/v). Three different adsorbents are tested, two of them are granular activated carbon (GAC), and the last is an activated carbon fiber-cloth (ACFC). The adsorption isotherm data are fitted by different models by nonlinear regression. The Langmuir-Freundlich model appears to be the adequate one to describe the adsorption phenomena independently of the VOC considered or the adsorbent. The adsorbents present attractive adsorption capacity of the undesirable compounds in biogas atmosphere though the maximum adsorption capacities for a VOC are quite different from each other. The adsorption kinetics are characterized through three coefficients: the initial adsorption coefficient, the external film mass transfer coefficient and the internal diffusion coefficient of Weber. The ACFC demonstrates advanced kinetic yields compared to the granular activated carbon materials whatever VOC is considered. Therefore, pre-upgrading of biogas produced from wastewater sludge or co-digestion system by adsorption onto activated carbon appears worth investigating. Especially with ACFC material that presents correct adsorption capacities toward VOCs and concrete regeneration process opportunity to realize such process.

  6. The role of neutron activation analysis and radioanalytical methods in dose-effect relationship studies for the setting of trace metal protection criteria

    Sabbioni, E.; Pietra, R.; Edel, J.; Goetz, L.

    1986-01-01

    In order to prepare a scientifically accurate health protection criteria documents for trace metals integrated multidisciplinary research is necessary. In particular, the rational for structuring the documents should be based primarily on the two major questions of exposure and response. Unfortunately, in a majority of cases there is a paucity of relevant data to the establishment of dose-effect relationships. This work intends to show the role that neutron activation analysis and radiotracers with very high specific radioactivity have in solving problems relevant for establishment dose-effect relationships for trace metals. Typical applications in the different research areas involved in the preparation of the protection criteria, from source and exposure to levels and forms of trace metals in humans, are presented. (author)

  7. Implementation and outcomes of an active defaulter tracing system for HIV, prevention of mother to child transmission of HIV (PMTCT), and TB patients in Kibera, Nairobi, Kenya.

    Thomson, Kerry A; Cheti, Erastus O; Reid, Tony

    2011-06-01

    Retention of patients in long term care and adherence to treatment regimens are a constant challenge for HIV, prevention of mother to child transmission of HIV (PMTCT), and TB programmes in sub-Saharan Africa. This study describes the implementation and outcomes of an active defaulter tracing system used to reduce loss to follow-up (LTFU) among HIV, PMTCT, TB, and HIV/TB co-infected patients receiving treatment at three Médecins Sans Frontières clinics in the informal settlement of Kibera, Nairobi, Kenya. Patients are routinely contacted by a social worker via telephone, in-person visit, or both very soon after they miss an appointment. Patient outcomes identified through 1066 tracing activities conducted between 1 April 2008 and 31 March 2009 included: 59.4% returned to the clinic, 9.0% unable to return to clinic, 6.3% died, 4.7% refused to return to clinic, 4.5% went to a different clinic, and 0.8% were hospitalized. Fifteen percent of patients identified for tracing could not be contacted. LTFU among all HIV patients decreased from 21.2% in 2006 to 11.5% in 2009. An active defaulter tracing system is feasible in a resource poor setting, solicits feedback from patients, retains a mobile population of patients in care, and reduces LTFU among HIV, PMTCT, and TB patients. Copyright © 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

  8. Zincon-modified activated carbon for solid-phase extraction and preconcentration of trace lead and chromium from environmental samples.

    Li, Zhenhua; Chang, Xijun; Hu, Zheng; Huang, Xinping; Zou, Xiaojun; Wu, Qiong; Nie, Rong

    2009-07-15

    A new method that utilizes zincon-modified activated carbon (AC-ZCN) as a solid-phase extractant has been developed for simultaneous preconcentration of trace Cr(III) and Pb(II) prior to the measurement by inductively coupled plasma optical emission spectrometry (ICP-OES). The separation/preconcentration conditions of analytes were investigated, including effects of pH, the shaking time, the sample flow rate and volume, the elution condition and the interfering ions. At pH 4, the maximum adsorption capacity of Cr(III) and Pb(II) onto the AC-ZCN were 17.9 and 26.7 mg g(-1), respectively. The adsorbed metal ions were quantitatively eluted by 1 mL of 0.1 mol L(-1) HCl. Common coexisting ions did not interfere with the separation. According to the definition of IUPAC, the detection limits (3 sigma) of this method for Cr(III) and Pb(II) were 0.91 and 0.65 ng mL(-1), respectively. The relative standard deviation under optimum condition is less than 3.5% (n=8). The method has been applied for the determination of Cr(III) and Pb(II) in biological materials and water samples with satisfactory results.

  9. Major, trace and rate earth elements in sediments of the Julian Adame-Alatorre dam by instrumental neutron activation analysis

    Mireles, F.; Pinedo, J. L.; Davila, J. I.; Oliva, J. E. [Universidad Autonoma de Zacatecas, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Speakman, R. J. [Museum Conservation Institute, Smithsonian Institution, Suitland, MD 20746 (United States); Glascock, M. D., E-mail: fmireles@uaz.edu.m [Research Reactor Center, University of Missouri, Columbia, MO 65211 (United States)

    2010-10-15

    The rapid industrial development in regions of Mexico during recent years has had the side effect of introducing toxic metals, fertilizers, and pesticides into the ecosystem. Sediment cores were collected from eight locations around the Julian Adame-Alatorre dam located in Municipality of Villanueva in the Zacatecas State, Mexico. The cores were analyzed for 32 major, trace, and rare earth elements (As, La, Lu, Nd, Sm, U, Yb, Ce, Co, Cr, Cs, Eu, Fe, Hf, Rb, Sb, Sc, Sr, Ta, Tb, Th, Zn, Zr, Al, Ba, Ca, Dy, K, Mn, Na, Ti, V) in order to estimate the health risk. The samples were analyzed by instrument neutron activation analysis using thermal neutron fluxes of 8 x 10{sup 13} and 5 x 10{sup 13} n cm{sup -2} s{sup -1} for short and long irradiations, respectively. The results of the contamination levels for elements such as As, Ba, Cr, Fe, Mn, Ta, V, and Zn were compared with the Mexican regulations and the guidelines of US EPA. (Author)

  10. Major, trace and rate earth elements in sediments of the Julian Adame-Alatorre dam by instrumental neutron activation analysis

    Mireles, F.; Pinedo, J. L.; Davila, J. I.; Oliva, J. E.; Speakman, R. J.; Glascock, M. D.

    2010-10-01

    The rapid industrial development in regions of Mexico during recent years has had the side effect of introducing toxic metals, fertilizers, and pesticides into the ecosystem. Sediment cores were collected from eight locations around the Julian Adame-Alatorre dam located in Municipality of Villanueva in the Zacatecas State, Mexico. The cores were analyzed for 32 major, trace, and rare earth elements (As, La, Lu, Nd, Sm, U, Yb, Ce, Co, Cr, Cs, Eu, Fe, Hf, Rb, Sb, Sc, Sr, Ta, Tb, Th, Zn, Zr, Al, Ba, Ca, Dy, K, Mn, Na, Ti, V) in order to estimate the health risk. The samples were analyzed by instrument neutron activation analysis using thermal neutron fluxes of 8 x 10 13 and 5 x 10 13 n cm -2 s -1 for short and long irradiations, respectively. The results of the contamination levels for elements such as As, Ba, Cr, Fe, Mn, Ta, V, and Zn were compared with the Mexican regulations and the guidelines of US EPA. (Author)

  11. The effects of mediator and granular activated carbon addition on degradation of trace organic contaminants by an enzymatic membrane reactor.

    Nguyen, Luong N; Hai, Faisal I; Price, William E; Leusch, Frederic D L; Roddick, Felicity; Ngo, Hao H; Guo, Wenshan; Magram, Saleh F; Nghiem, Long D

    2014-09-01

    The removal of four recalcitrant trace organic contaminants (TrOCs), namely carbamazepine, diclofenac, sulfamethoxazole and atrazine by laccase in an enzymatic membrane reactor (EMR) was studied. Laccases are not effective for degrading non-phenolic compounds; nevertheless, 22-55% removal of these four TrOCs was achieved by the laccase EMR. Addition of the redox-mediator syringaldehyde (SA) to the EMR resulted in a notable dose-dependent improvement (15-45%) of TrOC removal affected by inherent TrOC properties and loading rates. However, SA addition resulted in a concomitant increase in the toxicity of the treated effluent. A further 14-25% improvement in aqueous phase removal of the TrOCs was consistently observed following a one-off dosing of 3g/L granular activated carbon (GAC). Mass balance analysis reveals that this improvement was not due solely to adsorption but also enhanced biodegradation. GAC addition also reduced membrane fouling and the SA-induced toxicity of the effluent. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Synchrotron radiation and free electron laser activities in Novosibirsk

    Korchuganov, V.N.; Kulipanov, G.N.; Mezentsev, N.A.; Oreshkov, A.D.; Panchenko, V.E.; Pindyurin, V.F.; Skrinskij, A.N.; Sheromov, M.A.; Vinokurov, N.A.; Zolotarev, K.V.

    1994-01-01

    The results of studies realized in the Siberian synchrotron radiation centre within the frameworks of wide program of synchrotron radiation and free electron laser research are summarized. The technical information on the VEPP-2M, VEPP-3 and VEPP-4M storage rings used as synchrotron radiation sources is given. 10 refs.; 8 figs.; 12 tabs

  13. Report of activities of the radiation medicine sector - 1983

    1984-01-01

    The radiation medicine programs, participation in work groups, bibliography about radiation medicine, systematic register of nuclear accidents, technical-scientifical interexchange, participation in congress, seminaries and others events, elaboration of technical-scientifical works, bibliographical consults, participation in palestras of Prevention Weeks of Work Accidents, training in hygiene of ionizing radiations and so on, are the topics presented. (M.A.C.) [pt

  14. Study on regeneration of activated carbon by means of electron radiation

    Zhu Guanghua; Arai, H.; Hosono, M.

    1991-01-01

    The results of regeneration of activated carbon adsorbing sodium lauryl sulfate (SLS) by 2 MeV electron radiation, and the dependence of the regeneration rate of activated carbon on the electron current intensity, the temperature of sample and the atmosphere were reported. It is shown that regeneration of activated carbon by electron radiation is full of promise

  15. Extratropical Weather Systems on Mars: Radiatively-Active Water Ice Effects

    Hollingsworth, J. L.; Kahre, M. A.; Haberle, R. M.; Urata, R. A.; Montmessin, F.

    2017-01-01

    Extratropical, large-scale weather disturbances, namely transient, synoptic-period,baroclinic barotropic eddies - or - low- (high-) pressure cyclones (anticyclones), are components fundamental to global circulation patterns for rapidly rotating, differentially heated, shallow atmospheres such as Earth and Mars. Such "wave-like" disturbances that arise via (geophysical) fluid shear instability develop, mature and decay, and travel west-to-east in the middle and high latitudes within terrestrial-like planetary atmospheres. These disturbances serve as critical agents in the transport of heat and momentum between low and high latitudes of the planet. Moreover, they transport trace species within the atmosphere (e.g., water vapor/ice, other aerosols (dust), chemical species, etc). Between early autumn through early spring, middle and high latitudes on Mars exhibit strong equator-to-pole mean temperature contrasts (i.e., "baroclinicity"). Data collected during the Viking era and observations from both the Mars Global Surveyor (MGS) and Mars Reconnaissance Orbiter (MRO) indicate that such strong baroclinicity supports vigorous, large-scale eastward traveling weather systems [Banfield et al., 2004; Barnes et al., 1993]. A good example of traveling weather systems, frontal wave activity and sequestered dust activity from MGS/MOC image analyses is provided in Figure 1 (cf. Wang et al. [2005]). Utilizing an upgraded and evolving version of the NASA Ames Research Center (ARC) Mars global climate model, investigated here are key dynamical and physical aspects of simulated northern hemisphere (NH) large-scale extratropica lweather systems,with and without radiatively-active water ice clouds. Mars Climate Model:

  16. Activities on calibration of radiation protection instruments in Indonesia

    Trijoko, S.

    1995-01-01

    As the use of the ionizing radiation emitted by radionuclides or produced by modern machines in Indonesia has increased significantly in the past two decades, the demand for radiation protection measures has also grown up very rapidly. In the mind of Indonesian people, ionizing radiation is always associated with atomic bombs. Indonesian government has set up National Atomic Energy Agency (BATAN) through the Act No. 31/1964. The BATAN has responsibility in the research and development, implementation and inspection of the safe use of ionizing radiation for peaceful purposes, and always put a great concern on radiation protection matter. The Center for Standardization and Radiation Safety Research (CSRSR) has been founded to implement research and services in the fields of radiation safety, standardization, dosimetry, radiation health, as well as the application of nuclear techniques to medicine. In order to provide the national reference in terms of radiation dosimetry and calibration, the Secondary Standard Dosimetry Laboratory was completely set up in Jakarta by 1984. As available facilities, radiation instruments and radiation sources are described. Calibration and personal monitoring services are reported. (K.I.)

  17. Metal and trace element sediment assessment from Ribeira do Iguape river, Sao Paulo state, Brazil, by instrumental neutron activation analysis

    Castro, Francisco J.V. de; Quinaglia, Gilson A., E-mail: franciscovc@cetesbnet.sp.gov.br, E-mail: gilsonn@cetesbnet.sp.gov.br [CETESB - Companhia Ambiental do Estado de Sao Paulo, SP (Brazil). ELTA - Setor de Analises Toxicologicas; Favaro, Deborah I.T., E-mail: defavaro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (LAN/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Laboratorio de Analise por Ativacao Neutronica; Franklin, Robson L.; Ferreira, Francisco J., E-mail: robsonf@cetesbnet.sp.gov.br, E-mail: franciscoj@cetesbnet.sp.gov.br [CETESB - Companhia Ambiental do Estado de Sao Paulo, SP (Brazil). ELAI - Setor de Quimica Inorganica

    2011-07-01

    The watershed region of the Ribeira do Iguape River and the estuarine complex of the Paranagua-Iguape- Cananeia and the various river basins located between this region and the Atlantic Ocean, is known as the Ribeira Valley. The Ribeira do Iguape River runs a total length of approximately 470 km, being the main source of fresh water in the Estuarine Complex of the Iguape-Cananeia-Paranagua (Lagamar). The Ribeira do Iguape River is the last major river in the State of Sao Paulo that has not been altered by dams. During virtually the entire 20th century, the region of the Ribeira Valley was the scene of constant environmental degradation resulting from the intense exploration and refining of lead, zinc and silver ores that were processed in the mines of the region, in a rudimentary way and without any control over environmental impacts. Since 1996, all such activities ceased, however, leaving behind a huge amount of environmental liabilities. This study aims to investigate the presence and concentration levels of metals and semi-metals arsenic (As), cadmium (Cd) and lead (Pb) in the sediment and water of aquatic systems of Ribeira do Iguape River and its tributaries, for an environmental assessment and monitoring of the region. The determination of these elements was carried out by GF AAS technique for water samples and ICP OES for the sediment samples. This study also assessed the occurrence of some major (Ca, Fe, K and Na), trace (As, Ba, Br, Co, Cs, Hf, Rb, Sb, Sc, Se, Ta, Th, U, Zn) and rare earth elements (La, Ce, Eu, Nd, Sm, Lu, Tb and Yb) by Neutron Activation Analysis (NAA). Validation of both methodologies, according to precision and accuracy, was done by reference material analyses. The results obtained for As, Cd and Pb were compared to the Canadian Environmental oriented values (TEL and PEL). The results obtained for multielemental analyses in the sediment samples were compared to UCC values (Upper Continental Crust). (author)

  18. Metal and trace element sediment assessment from Ribeira do Iguape river, Sao Paulo state, Brazil, by instrumental neutron activation analysis

    Castro, Francisco J.V. de; Quinaglia, Gilson A.; Favaro, Deborah I.T.; Franklin, Robson L.; Ferreira, Francisco J.

    2011-01-01

    The watershed region of the Ribeira do Iguape River and the estuarine complex of the Paranagua-Iguape- Cananeia and the various river basins located between this region and the Atlantic Ocean, is known as the Ribeira Valley. The Ribeira do Iguape River runs a total length of approximately 470 km, being the main source of fresh water in the Estuarine Complex of the Iguape-Cananeia-Paranagua (Lagamar). The Ribeira do Iguape River is the last major river in the State of Sao Paulo that has not been altered by dams. During virtually the entire 20th century, the region of the Ribeira Valley was the scene of constant environmental degradation resulting from the intense exploration and refining of lead, zinc and silver ores that were processed in the mines of the region, in a rudimentary way and without any control over environmental impacts. Since 1996, all such activities ceased, however, leaving behind a huge amount of environmental liabilities. This study aims to investigate the presence and concentration levels of metals and semi-metals arsenic (As), cadmium (Cd) and lead (Pb) in the sediment and water of aquatic systems of Ribeira do Iguape River and its tributaries, for an environmental assessment and monitoring of the region. The determination of these elements was carried out by GF AAS technique for water samples and ICP OES for the sediment samples. This study also assessed the occurrence of some major (Ca, Fe, K and Na), trace (As, Ba, Br, Co, Cs, Hf, Rb, Sb, Sc, Se, Ta, Th, U, Zn) and rare earth elements (La, Ce, Eu, Nd, Sm, Lu, Tb and Yb) by Neutron Activation Analysis (NAA). Validation of both methodologies, according to precision and accuracy, was done by reference material analyses. The results obtained for As, Cd and Pb were compared to the Canadian Environmental oriented values (TEL and PEL). The results obtained for multielemental analyses in the sediment samples were compared to UCC values (Upper Continental Crust). (author)

  19. Stanford Synchrotron Radiation Laboratory. Activity report for 1988

    Cantwell, K. [ed.

    1996-01-01

    For SSRL operations, 1988 was a year of stark contrasts. The first extended PEP parasitic running since the construction of our two beam lines on that storage ring took place in November and December. Four experiments discussed below, were performed and detailed operational procedures which allowed synchrotron radiation an high energy users to coexist were established. SSRL anticipates that there will be significant amounts of beam time when PEP is run again for high energy physics. On the other hand, activity on SPEAR consisted of brief parasitic running on the VUV lines in December when the ring was operated at 1.85 GeV for colliding beam experiments. There was no dedicated SPEAR running throughout the entire calendar year. This is the first time since dedicated SPEAR operation was initiated in 1980 that there was no such running. The decision was motivated by both cost and performance factors, as discussed in Section 1 of this report. Fortunately, SLAC and SSRL have reached an agreement on SPEAR and PEP dedicated time charges which eliminates the cost volatility which was so important in the cancellation of the June-July dedicated SPEAR run. As discussed in Section 2, the 3 GeV SPEAR injector construction is proceeding on budget and on schedule. The injector will overcome the difficulties associated with the SLC-era constraint of only two injections per day. SSR and SLAC have also embarked on a program to upgrade SPEAR to achieve high reliability and performance. As a consequence, SSRL`s users may anticipate a highly effective SPEAR by 1991, at the latest. At that time, SPEAR is expected to be fully dedicated to synchrotron radiation research and operated by SSRL. Also contained in this report is a discussion of the improvements to SSRL`s experimental facilities and highlights of the experiments of the past year.

  20. Stanford Synchrotron Radiation Laboratory. Activity report for 1988

    Cantwell, K.

    1996-01-01

    For SSRL operations, 1988 was a year of stark contrasts. The first extended PEP parasitic running since the construction of our two beam lines on that storage ring took place in November and December. Four experiments discussed below, were performed and detailed operational procedures which allowed synchrotron radiation an high energy users to coexist were established. SSRL anticipates that there will be significant amounts of beam time when PEP is run again for high energy physics. On the other hand, activity on SPEAR consisted of brief parasitic running on the VUV lines in December when the ring was operated at 1.85 GeV for colliding beam experiments. There was no dedicated SPEAR running throughout the entire calendar year. This is the first time since dedicated SPEAR operation was initiated in 1980 that there was no such running. The decision was motivated by both cost and performance factors, as discussed in Section 1 of this report. Fortunately, SLAC and SSRL have reached an agreement on SPEAR and PEP dedicated time charges which eliminates the cost volatility which was so important in the cancellation of the June-July dedicated SPEAR run. As discussed in Section 2, the 3 GeV SPEAR injector construction is proceeding on budget and on schedule. The injector will overcome the difficulties associated with the SLC-era constraint of only two injections per day. SSR and SLAC have also embarked on a program to upgrade SPEAR to achieve high reliability and performance. As a consequence, SSRL's users may anticipate a highly effective SPEAR by 1991, at the latest. At that time, SPEAR is expected to be fully dedicated to synchrotron radiation research and operated by SSRL. Also contained in this report is a discussion of the improvements to SSRL's experimental facilities and highlights of the experiments of the past year

  1. Study of the trace element in organisms by neutron activation analysis, 1. Multielement instrumental neutron activation analysis of cannabis

    Shinogi, M; Murai, Y; Mori, I [Kobe Women' s Coll. of Pharmacy (Japan); Takeuchi, T

    1974-12-01

    Examinations were made on optimal experimental conditions for instrumental determination of various elements in cannabis by neutron activation analysis, without any radiochemical separation, and the following conditions were found to be useful. Irradiation samples to be used are about 300 mg of the leaves or stem bark, and about 100 mg of the root. For soil sample, about 50 mg is used for the determination of short half-life nuclides and about 300 mg for long half-life nuclides. For short half-life nuclides, the samples are irradiated for 1 min, activity is measured for 200 sec after a decay of 3 min, and for 400 sec after a decay of 10 min. For long half-life nuclides, the samples are irradiated for 60 min and the activites are measured for 4 K sec after 1 week and for 10 K sec after 1 month. Use of supersonic waves is also convenient for cleansing of the samples. Thirty-five kinds of interesting elements were determined by this method from cannabis cultivated in Maizuru area.

  2. Cre Activated and Inactivated Recombinant Adeno-Associated Viral Vectors for Neuronal Anatomical Tracing or Activity Manipulation.

    Saunders, Arpiar; Sabatini, Bernardo L

    2015-07-01

    Recombinant adeno-associated viruses (rAAVs) transcriptionally activated by Cre recombinase (Cre-On) are powerful tools for determining the anatomy and function of genetically defined neuronal types in transgenic Cre driver mice. Here we describe how rAAVs transcriptionally inactivated by Cre (Cre-Off) can be used in conjunction with Cre-On rAAVs or genomic Cre-reporter alleles to study brain circuits. Intracranial injection of Cre-On/Cre-Off rAAVs into spatially intermingled Cre(+) and Cre(-) neurons allows these populations to be differentially labeled or manipulated within individual animals. This comparison helps define the unique properties of Cre(+) neurons, highlighting the specialized role they play in their constituent brain circuits. This protocol touches on the conceptual and experimental background of Cre-Off rAAV systems, including caveats and methods of validation. Copyright © 2015 John Wiley & Sons, Inc.

  3. Activities of Institute of Radiation Protection and Dosimety/Brazil as Technical and Scientific Support Organization on Occupational Radiation Protection

    Da Silva, F.C.A.; Ferreira, P.R.; Matta, L.E.C.; Peres, M.A.L.; Godoy, J.M.; Alencar, M.A.V.; Carlos, M.T.; Souza-Santos, D.; Leocadio, J.C.; Oliveira, M.S.

    2010-01-01

    There are, in Brazil, about 126,000 workers registered on National Dose Registry System (SRD/IRD) as occupationally exposed. They work on 4,000 radioactive installations, 20 nuclear fuel cycle installations and with 90,000 x-ray diagnostic devices. There are two main Regulatory Authorities to license and control these installations on nuclear and radioactive areas, and another Regulatory Authority that is responsible for safety and health protection of workers on their labour activities. Belonging to structure of the National Commission of Nuclear Energy (CNEN-Brazil) there is an Institute dedicated to radiation protection, dosimetry and metrology of ionizing radiation, that is the Institute of Radiation Protection and Dosimetry (IRD). This paper presents two main IRD activities related to occupational radiation protection that can be seen as example of technical and scientific support to Regulatory Authorities: the Radiation Overexposure Analysis that is performed by the Radiation Overexposure Analysis Group (GADE) and the Approval of Individual Monitoring Services and Calibration Laboratory of Equipment used in Radiation Protection that is performed by the Committee for the Evaluation of Essay and Calibration Services (CASEC). (author)

  4. Device Simulation of Monolithic Active Pixel Sensors: Radiation Damage Effects

    Fourches, N.T.

    2009-01-01

    Vertexing for the future International Linear Collider represents a challenging goal because of the high spatial resolution required with low material budget and high ionizing radiation tolerance. CMOS Monolithic Active Pixel Sensors (MAPS) represent a good potential solution for this purpose. Up to now many MAPS sensors have been developed. They are based on various architectures and manufactured in different processes. However, up so far, the sensor diode has not been the subject of extensive modelization and simulation. Published simulation studies of sensor-signal formation have been less numerous than measurements on real sensors. This is a cause for concern because such sensor is physically based on the partially depleted diode, in the vicinity of which the electric field collects the minority carriers generated by an incident MIP (minimum ionizing particle). Although the microscopic mechanisms are well known and modelled, the global physical mechanisms for signal formation are not very rigorously established. This is partly due to the presence of a predominant diffusion component in the charge transport. We present here simulations mainly based on the S-PISCES code, in which physical mechanisms affecting transport are taken into account. Diffusion, influence of residual carrier concentration due to the doping level in the sensitive volume, and more importantly charge trapping due to deep levels in the active (detecting) layer are studied together with geometric aspects. The effect of neutron irradiation is studied to assess the effects of deep traps. A comparison with available experimental data, obtained on processed MAPS before or after neutron irradiation will be introduced. Simulated reconstruction of the Minimum Ionizing Particle (MIP) point of impact in two dimensions is also investigated. For further steps, guidelines for process choices of next Monolithic Active Pixel Sensors are introduced. (authors)

  5. Determination of trace elements of Egyptian crops by neutron activation analysis. Pt. 3. Trace elements in African tea, ginger, canella bark, black pepper, sesame, lady's fingers, jew's mallow, tomatos, cucumber and marrow

    Sherif, M K; Awadallah, R M; Amrallah, A H [Assiut Univ. (Egypt)

    1980-01-01

    Multielemental neutron activation analysis was used for the determination of Al, As, Au, Br, Ca, Cd, Co, Cr, Cu, Fe, La, Mn, Mo, Sb, Se, W and Zn in African tea and lady's fingers (Malvaceae Family), ginger (Zingiperanceae Family), canella bark (Laureceae Family), black pepper (Piperaceae Family), cucumber seeds and vegetable marrow seeds (Cucurbitaceae Family), tomatos seed (Solanaceae Family), safflower seeds (Compositae Family), jew's mallow seed (Tiliaceae Family) and sesame (Pedaliaceae Family). Trace elements determination was made for the analysis of destructive (using super pure nitric acid and adsorbing the metal-APDC and metal-Dz complexes on activated charcoal) and nondestructive (dry seeds) samples. The method is simple, precise and sensitive for the determination of microamounts of the elements (ppM to ppB).

  6. Sampling trace organic compounds in water: a comparison of a continuous active sampler to continuous passive and discrete sampling methods.

    Coes, Alissa L; Paretti, Nicholas V; Foreman, William T; Iverson, Jana L; Alvarez, David A

    2014-03-01

    A continuous active sampling method was compared to continuous passive and discrete sampling methods for the sampling of trace organic compounds (TOCs) in water. Results from each method are compared and contrasted in order to provide information for future investigators to use while selecting appropriate sampling methods for their research. The continuous low-level aquatic monitoring (CLAM) sampler (C.I.Agent® Storm-Water Solutions) is a submersible, low flow-rate sampler, that continuously draws water through solid-phase extraction media. CLAM samplers were deployed at two wastewater-dominated stream field sites in conjunction with the deployment of polar organic chemical integrative samplers (POCIS) and the collection of discrete (grab) water samples. All samples were analyzed for a suite of 69 TOCs. The CLAM and POCIS samples represent time-integrated samples that accumulate the TOCs present in the water over the deployment period (19-23 h for CLAM and 29 days for POCIS); the discrete samples represent only the TOCs present in the water at the time and place of sampling. Non-metric multi-dimensional scaling and cluster analysis were used to examine patterns in both TOC detections and relative concentrations between the three sampling methods. A greater number of TOCs were detected in the CLAM samples than in corresponding discrete and POCIS samples, but TOC concentrations in the CLAM samples were significantly lower than in the discrete and (or) POCIS samples. Thirteen TOCs of varying polarity were detected by all of the three methods. TOC detections and concentrations obtained by the three sampling methods, however, are dependent on multiple factors. This study found that stream discharge, constituent loading, and compound type all affected TOC concentrations detected by each method. In addition, TOC detections and concentrations were affected by the reporting limits, bias, recovery, and performance of each method. Published by Elsevier B.V.

  7. Sampling trace organic compounds in water: a comparison of a continuous active sampler to continuous passive and discrete sampling methods

    Coes, Alissa L.; Paretti, Nicholas V.; Foreman, William T.; Iverson, Jana L.; Alvarez, David A.

    2014-01-01

    A continuous active sampling method was compared to continuous passive and discrete sampling methods for the sampling of trace organic compounds (TOCs) in water. Results from each method are compared and contrasted in order to provide information for future investigators to use while selecting appropriate sampling methods for their research. The continuous low-level aquatic monitoring (CLAM) sampler (C.I.Agent® Storm-Water Solutions) is a submersible, low flow-rate sampler, that continuously draws water through solid-phase extraction media. CLAM samplers were deployed at two wastewater-dominated stream field sites in conjunction with the deployment of polar organic chemical integrative samplers (POCIS) and the collection of discrete (grab) water samples. All samples were analyzed for a suite of 69 TOCs. The CLAM and POCIS samples represent time-integrated samples that accumulate the TOCs present in the water over the deployment period (19–23 h for CLAM and 29 days for POCIS); the discrete samples represent only the TOCs present in the water at the time and place of sampling. Non-metric multi-dimensional scaling and cluster analysis were used to examine patterns in both TOC detections and relative concentrations between the three sampling methods. A greater number of TOCs were detected in the CLAM samples than in corresponding discrete and POCIS samples, but TOC concentrations in the CLAM samples were significantly lower than in the discrete and (or) POCIS samples. Thirteen TOCs of varying polarity were detected by all of the three methods. TOC detections and concentrations obtained by the three sampling methods, however, are dependent on multiple factors. This study found that stream discharge, constituent loading, and compound type all affected TOC concentrations detected by each method. In addition, TOC detections and concentrations were affected by the reporting limits, bias, recovery, and performance of each method.

  8. Active Radiation Level Measurement on New Laboratory Instrument for Evaluating the Antibacterial Activity of Radioisotope

    Joh, Eunha; Park, Jang Guen

    2014-01-01

    A disc method has been widely used to measure the antibacterial effect of chemical agents. However, it is difficult to measure the antibacterial effect of radioisotopes using a disc method. A disc method is a method for diffusing a drug by placing the drug containing disc on the medium. In this method, radioisotopes are diffused on the medium and it is difficult to measure the exact effect by radiation. Thus, new laboratory equipment needs to evaluate the antibacterial activity by the radioisotopes. In this study, we measured the radiation level of radioisotopes on a new laboratory instrument using a MCNP. A disc method has been widely used to measure the antibacterial effect of chemical agents. This method uses a drug diffusion system for the measurement of anti-bacterial antibiotics. To measure the antimicrobial activity of a radioisotope, a new type of laboratory instrument is necessary to prevent the drug from spreading. The radioisotopes are used to diagnose and treat cancer. However, studies for anti-biotical use have not progressed. The radiation of radioisotopes has the effect of killing bacteria. Before this study proceeds further, it is necessary to be able to measure the antimicrobial activity of the radioisotope easily in the laboratory. However, in this study, it was possible to measure the antimicrobial activity of the radioisotope in the laboratory using a new laboratory instrument. We intend to start evaluation studies of the antibacterial activity of specific radioisotopes. In addition, it will be possible to develop research to overcome diseases caused by bacteria in the future

  9. Active Radiation Level Measurement on New Laboratory Instrument for Evaluating the Antibacterial Activity of Radioisotope

    Joh, Eunha; Park, Jang Guen [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    A disc method has been widely used to measure the antibacterial effect of chemical agents. However, it is difficult to measure the antibacterial effect of radioisotopes using a disc method. A disc method is a method for diffusing a drug by placing the drug containing disc on the medium. In this method, radioisotopes are diffused on the medium and it is difficult to measure the exact effect by radiation. Thus, new laboratory equipment needs to evaluate the antibacterial activity by the radioisotopes. In this study, we measured the radiation level of radioisotopes on a new laboratory instrument using a MCNP. A disc method has been widely used to measure the antibacterial effect of chemical agents. This method uses a drug diffusion system for the measurement of anti-bacterial antibiotics. To measure the antimicrobial activity of a radioisotope, a new type of laboratory instrument is necessary to prevent the drug from spreading. The radioisotopes are used to diagnose and treat cancer. However, studies for anti-biotical use have not progressed. The radiation of radioisotopes has the effect of killing bacteria. Before this study proceeds further, it is necessary to be able to measure the antimicrobial activity of the radioisotope easily in the laboratory. However, in this study, it was possible to measure the antimicrobial activity of the radioisotope in the laboratory using a new laboratory instrument. We intend to start evaluation studies of the antibacterial activity of specific radioisotopes. In addition, it will be possible to develop research to overcome diseases caused by bacteria in the future.

  10. Neutron activation analysis in trace element determinaton in studies of wound healing and in the framework of dose-effect studies on platinum-containing cancer chemotherapeutics

    Trebert Haeberlin, S.

    1986-01-01

    The origin of the iron concentration in wound tissues was studied. To differentiate between blood and tissue iron the erythrocytes of a rabbit were marked with radioactive 55 Fe. Under the assumption that the half-life of rabbit erythrocytes of 34.5 days would not be changed by 55 Fe marking, the 55 Fe activity found in samples taken from the wound area of muscle cut wounds in a healing time of up to 14 days should be a measure for the blood iron share in the wound. The total iron content was determined be measuring 59 Fe with the help of NAA. The portion of iron which was from the tissues was found as the difference between total iron (NAA) and blood iron ( 55 Fe). The activation analysis of the samples from the wound tissues was supposed to give information about the participation of other essential trace elements in wound healing. In the framework of the development of new cancer chemotherapeutics with a specific effect on hormone-dependent mammary carcinoma, the distribution of the respective medications in tumor tissues and organs of rats and mice based on the activation analysis determination of platinum content in tissues of interest was ascertained. In the activation analyses for platinum determination the amounts in the samples of other essential trace elements was also determined, in order to ascertain characteristic accumulation or reduction of trace elements in various tissues as a result of tumor development or in connection with therapy. (orig./MG) [de

  11. An experimental search for gamma radiation associated with thunderstorm activity

    Fryberger, D.

    1992-11-01

    This experiment is a repeat of an earlier experiment, but with more sensitive apparatus and in a location with a higher incidence of thunderstorm activity. The earlier experiment was undertaken by Ashby and Whitehead to investigate the theory that ball lightning might be associated with the annihilation of small amounts of antimatter, and it yielded some very interesting but inconclusive results. In the course of about 12 months of data taking, four high rate bursts of gamma radiation were detected. These events lasted a few seconds and had many thousands of counts (16500, 5000, 3700, and > 7700. Unfortunately, the association of these gamma ray bursts with thunderstorms or ball lightning was not clearly established, although one of the bursts did occur during a local thunderstorm in rough coincidence with a lightning bolt striking a flagpole about 100 yards from the gamma ray detection crystals. A pulse height spectrum taken for this burst (no spectrum was taken for the other three) exhibited a significant peak, well above background, the energy of which appeared to be compatible with the 511 keV positron annihilation line. While the peak could not be unambiguously attributed to positron annihilation, this certainly appeared to be the most likely source

  12. Hyperspectral estimation of corn fraction of photosynthetically active radiation

    Yang Fei; Zhang Bai; Song Kaishan

    2008-01-01

    Fraction of absorbed photosynthetically active radiation (FPAR) is one of the important variables in many productivity and biomass estimation models, this analyzed the effect of FPAR estimation with hyperspectral information, which could provide the scientific support on the improvement of FPAR estimation, remote sensing data validation, and the other ecological models. Based on the field experiment of corn, this paper analyzed the correlations between FPAR and spectral reflectance or the differential coefficient, and discussed the mechanism of FPAR estimation, studied corn FPAR estimation with reflectance, first differential coefficient, NDVI and RVI. The reflectance of visible bands showed much better correlations with FPAR than near-infrared bands. The correlation curve between FPAR and differential coefficient varied more frequently and greatly than the curve of FPAR and reflectance. Reflectance and differential coefficient both had good regressions with FPAR of the typical single band, with the maximum R2 of 0.791 and 0.882. In a word, differential coefficient and vegetation index were much effective than reflectance for corn FPAR estimating, and the stepwised regression of multibands differential coefficient showed the best regression with R2 of 0.944. 375 nm purpled band and 950 nm near-infraed band absorbed by water showed prodigious potential for FPAR estimating precision. On the whole, vegetation index and differential coefficient have good relationships with FPAR, and could be used for FAPR estimation. It would be effective of choosing right bands and excavating the hyperspectral data to improve FPAR estimating precision

  13. Radiation hygiene analysis of medical activities in Norway

    Lundgren, L.; Olerud, H.; Saxeboel, G.

    1987-01-01

    A status report from the project ''Radiation hygiene analysis of medical activities in Norway'' is presented. A principal project description as well as the main purpose of the project are presented. The report gives information on methods and strategy in connection with patient dose measurements and instrument calibration. The main task of the report is to present and explain the development of an analytical tool based on computer programs. At present, five different programs are produced, linked together in a menusystem. The programs deal with registration of observed variables, compute aritmetic mean/median values, make statistics,and plot and calculate integrated doses from X-ray examinations of interest. So far approximately 2200 X-ray examinations have been observed, each limited to 24 observation variables. The potential power of the analytical tool is demonstrated for the barium meal examination. The analysis indicates a mean integrated energy of 229 mJ per examination, while the annual collective dose from these examinations is 200 manSv in Norway. Discussion of facts relevant to optimization clearly shows that the use of 100 mm technique should be encouraged

  14. Activity of carbohydrate metabolism enzymes of bone marrow cells of rats affected by radiation

    Sukhomlinov, B.F.; Grinyuk, Yu.S.; Sibirnaya, N.A.; Starikovich, L.S.; Khmil', M.V.

    1990-01-01

    The influence of ionizing radiation (154.8 mC/kg on activity of some carbohydrate metabolism dehydrogenases in cells of the whole and fractionated rat bone marrow has been investigated. Different glucose metabolism units differently responded to radiation, the highest radiation response being exhibited by pentosophosphate cycle processes. The pattern of changes in the enzyme activity of different myelocaryocyte populations was shown to depend directly on the functional specilization of cells and the energy exchange types predominated in them

  15. Radiation Protection in the Application of Active Detection Technologies

    2013-07-01

    BECKER, S.M. (2004). “Emergency communication and information issues in terrorism events involving radioactive materials,” Biosecur Bioterror. 2(3...National Council on Radiation Protection and Measurements. Considerations Regarding the Unintended Radiation Exposure of the Embryo, Fetus or Nursing

  16. 4T CMOS Active Pixel Sensors under Ionizing Radiation

    Tan, J.

    2013-01-01

    This thesis investigates the ionizing radiation effects on 4T pixels and the elementary in-pixel test devices with regard to the electrical performance and the optical performance. In addition to an analysis of the macroscopic pixel parameter degradation, the radiation-induced degradation mechanisms

  17. Indirect effect of ionizing radiation on adehylate cyclase activity of liver cells in rat embryos

    Slozhenikina, L.V.; Ushakova, T.E.; Mikhajlets, L.P.; Kuzin, A.M.

    1980-01-01

    A comparative study was made of the effect of ionizing radiation on basal and catecholamine-stimulating activity of adenylate cyclase in the liver of 20-day embroys under in vivo and in vitro conditions (a membrane fraction and plasma membranes). The authors discuss the share of the indirect effect of radiation in modifying the adenylate cyclase activity

  18. A method of alpha-radiating nuclide activity measuring in aerosol filters

    Ignatov, V.P.; Galkina, V.N.

    1992-01-01

    Scintillation method of determination of alpha-radiating nuclide activity in aerosol filters was suggested. The method involves dissolution of the filter in organic solvent, introduction of luminophore into solution prepared, drying of the preparation and measurement of radionuclide activity. Dependences of alpha-radiation detection efficiency on the content of luminophore, filter material, colourless and coloured substances in preparations analyzed were considered

  19. Determination of trace and heavy metals in paprika and soil by neutron activation analysis and atomic absorption spectroscopy

    Karimian-Teherani, D; Altmann, H; Wallisch, G [Oesterreichisches Forschungszentrum Seibersdorf G.m.b.H. Inst. fuer Biologie; Kiss, I [Koezponti Elelmiszeripari Kutato Intezet, Budapest (Hungary); Kapeller, K [Zoeldsegtermesztesi Kutatointezet, Kalocsa (Hungary). Paprikakutato Allomas

    1983-01-01

    Various samples of Hungarian spice paprika plant (treated with Wuxal) and corresponding soils were analyzed for their Fe, Cr, Zn, Co, Br, As, K, Mn and La (only in soil samples) and Hg contents. Statistical analysis showed significant differences in the trace element contents between most cultivars and soils. There is a higher amount of trace elements in samples treated with Wuxal than in controls with the exception of As. Mostly the same situation is observed in samples of soil as in paprika. The only exception is the non-significant difference in the case of Fe and Co. Differences in mercury content of treated and untreated paprika samples were not significant.

  20. Determination of trace elements in Pre-Hispanic ceramics from Chile's Central Zone using instrumental neutron activation analysis

    Andonie, O; Munoz, L; Kohnnenkamp, I; Falabella, F

    2000-01-01

    The determination of the element composition in archaeological ceramics is an often unexplored potential, that could provide a unique set of data to verify regional economic and socio-political hypotheses. By chemically defining the elements in these materials, their manufacturing and production centers may be identified, as well as the territorial and social organization of the peoples. Appropriate analytical methodologies for this type of research are limited since there are strict requirements with reference to precision, sensitivity and detection limits, all characteristics that the activation analysis technique provides. The Chilean Nuclear Energy Commission, the University of Chile, the Smithsonian Institution and the International Atomic Energy Agency developed together a cooperative interregional project to promote interdisciplinary research, to resolve archaeological problems and to develop a new application for a nuclear analytical technique. Until this work was undertaken, no systematic studies of trace elements in archaeological ceramics had been done in Chile using the technique of Instrumental Neutron Activation Analysis (INAA). This analytical technique was used in this research to chemically characterize archaeological pieces with the sensitivity, precision and accuracy needed to be able to work with mathematical models that can or cannot establish relationships between the different samples. Protocols were defined first for preparing the pottery samples in order to generate representative samples that could be analyzed by INAA. The homogeneity in preparing the samples used was defined using a group of elements that could be determined by INAA with a precision under 2%. A group of 18 elements was selected and an analytical test procedure was planned that included the type of packaging for the irradiation, the irradiation times, decline and count, the standards to be used and the type of monitor for correcting the neutron flow. The methodology used