Energy Technology Data Exchange (ETDEWEB)

Understanding the link between the Sun and climate is vital in the current incidence of global climate change, and 10Be in natural archives constitutes an excellent tracer for this purpose. As cosmic rays enter the atmosphere, cosmogenic isotopes like 10Be and 14C are formed. Variations in solar activity modulate the amount of incoming cosmic rays, and thereby cosmogenic isotope production. Atmospherically produced 10Be enters natural archives such as sediments and glaciers by wet and dry deposition within about a year of production. 10Be from natural archives therefore provides information on past solar activity, and because these archives also contain climate information, solar activity and climate can be linked. One remaining question is to what degree 10Be in natural archives ...

International Nuclear Information System (INIS)

Neutron-rich He-, Li-, and Be-isotopes in the vicinity of the drip-line have been studied by "1"2C- and "1"4C-induced multi-nucleon transfer reactions on "1"0Be and "1"3","1"4C-targets. This study revealed unknown excited states in "8","1"0He, "1"0","1"1Li and in "1"3","1"4Be. Both excitation energies and widths have been measured. In some cases most probable spins and parities could be assigned to the particle-unstable states observed. (orig.).

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

Short communication.

Energy Technology Data Exchange (ETDEWEB)

Method for determining the concentration of atomic species in gases and solids. Measurement of at least two emission intensities from a species in a plasma containing the species after a sufficient time period has elapsed after the generation of the plasma and during a second time period, permits an instantaneous temperature to be established within the sample. The concentration of the atomic species to be determined is then derived from the known emission intensity of a predetermined concentration of that species in the sample at the measured temperature, a quantity which is measured prior to the determination of the unknown concentration, and the actual measured emission from the unknown species, or by this latter emission and the emission intensity of a species having known concentration within ...

International Nuclear Information System (INIS)

In this paper, some results of the indoor radon concentration measurements are presented. Kodac track detectors LR 115, bare and in a cup were used for these measurements. Average winter/summer ratio was determined for the town of interest. (author). 5 refs, 1 fig., 1 tab.

Energy Technology Data Exchange (ETDEWEB)

Short-term radon measurements were used to make a comparison between weekly screening tests and seasonal concentration. The screening measurements were made in an indoor environment over a period of one quarter during early summer and the results are compared with the measured average radon level over that period. In these experiments, the envelope-type and plastic bag monitors were used for screening and long term radon concentration measurements, respectively. The results show that one cannot achieve predicting the seasonal mean radon concentration based on weekly measurements better than 50% under the conditions reported. (author).

Science.gov (United States)

Manganese, Iodine and Sulfide Concentrations and Peroxide to Oxygen Ratio Measured during the U.S. JGOFS Arabian Sea Process Study ...

CERN Document Server

In this work we develop a new propagation model for the Galactic cosmic rays based on the GALPROP code, including contributions from dark matter annihilation. The model predicts compatible Galactic diffuse $\\gamma$ ray spectra with EGRET data in all sky regions. It also gives consistent results of the diffuse $\\gamma$ ray longitude and latitude distributions. Further the results for B/C, $^{10}$Be/$^9$Be, proton, electron and antiproton spectra are also consistent with cosmic ray measurements. In the model we have taken a universal proton spectrum throughout the Galaxy without introducing large fluctuation for the proton energy loss is negligible. The dark matter annihilation signals are `boosted' after taking the contribution from subhalos into account. Another interesting feature of the model is that it gives better description of the diffuse $\\gamma$ rays when taking the source distribution compatible with supernova ...

Energy Technology Data Exchange (ETDEWEB)

Radium is known to be taken up by aquatic animals, and tends to accumulate in bone, shell and exoskeleton. The most common approach to estimating the uptake of a radionuclide by aquatic animals for use in health and environmental risk assessments is the concentration factor method. The concentration factor method relates the concentration of a contaminant in an organism to the concentration in the surrounding water. Site specific data are not usually available, and generic, default values are often used in risk assessment studies. This paper describes the concentration factor method, summarizes some of the variables which may influence the concentration factor for radium, reviews reported concentration factors measured in marine environments and presents concentration factors derived from data ...

International Nuclear Information System (INIS)

Short-duration measurements have been widely used to screen for exposures to elevated radon concentrations in individual houses or at state or regional levels. However, a number of factors, including spatial and temporal variability in radon concentrations, must be considered before comparison to concentration guidelines can be made. Daily variations in radon concentration can lead to inherent measurement uncertainties ranging from 20 to 100+ percent. Differences in radon concentration due to seasonal effects and/or sampling location are also variable, and do not appear to be regionally consistent. Winter/summer concentration ratios, for example, have been observed to vary by as much as a factor of 10 in basements and by a factor of 5 in first floors. In this paper the implications of these uncertainties on the use of ...

International Nuclear Information System (INIS)

Efforts has been made to specify surface ozone production in photochemical reaction due to the high concentration of NO_x and photon rays. The secondary reactions has been considered via optical measurements using actinometry and pyranometry which was followed for photochemical reactions at high temperature and because of air pollutants due to the traffic load and because of the inversion in certain days. The concentration of surface ozone which was measured in Tehran city center was in the range of 24- 45 ppb in 1991-1992 and a higher concentration of 45-65 ppb was measured in 1999-2000. This high surface ozone concentration could cause a severe damage to biota, fauna and human health.

International Nuclear Information System (INIS)

The standard deviation of measurement results of a given element in XRF spectrometry depends on three factors: concentration and concentration region, atomic number and matrix. The effects of these factors were investigated by an XRF instrument type ARL 72.000 for aluminium metal, bauxite-red mud and aluminium using computerized data processing. A comparison of linear and nonlinear relation between concentration and the result of XRF analysis was made for the determination of standard deviation. (R.P.).

Energy Technology Data Exchange (ETDEWEB)

Radon measurements were carried out in Kozlu, Karadon and Uzulmez underground coal mines of Zonguldak bituminous coal basin in Turkey. Passive-time integrating method, which is the most widely used technique for the measurement of radon concentration in air, was applied by using nuclear etched track detectors (CR-39) in the study area. The radon concentration measurements were performed on a total of 42 points in those three mines. The annual exposure, the annual effective dose and lifetime fatality risk, which are the important parameters for the health of workers, were estimated based on chronic occupational exposure to the radon gas, which is calculated using UNCEAR-2000 and ICRP-65 models. The radon concentrations at several coal production faces are higher than the action level of 1000 Bq m{sup -3}. It is suggested that the ventilation rates should be ...

Energy Technology Data Exchange (ETDEWEB)

Two methods for measuring indoor radon concentrations using activated charcoal have been tested. The first method is the well-known technique with direct gamma-measurements on the exposed canister after the sampling period. The other method uses a thermoluminescence dosemeter placed in the charcoal canister, giving an integrated value of the radon concentration.

International Nuclear Information System (INIS)

Radon concentration measurements were made in the interior of the great pyramid of ''Cheops'' at Giza. Measurements were carried out using CR-39 as a solid state nuclear track detector. The CR-39 sheets were placed inside the Queen's and King's chambers and along the ascending corridor leading to them. An evaluation of the radon concentration is presented and discussed. (author).

International Nuclear Information System (INIS)

After ten years investigation of radon seasonal variations at three very different locations, as well as radon concentration measurements in kindergartens and schools, systematical indoor radon measurements were undertaken in dwellings of Osijek. Indoor radon was measured by means of the LR-115 nuclear track detector at 48 town locations that gave the arithmetic mean of 71.6 Bq m"-"3, standard deviation of 44.0 Bq m"-"3 and geometric mean of 60.1 Bq m"-"3, for the radon concentration range from 23 to 186 Bq m"-"3. The empirical frequency distribution of radon concentrations, with the class width of 20 Bq m"-"3, was in accordance with the theoretical log-normal distribution which was shown with #chi#"2 - test. The radon map pointed out a region of higher radon concentrations (central part of the town) that was ascribed to the geological soil ...

International Nuclear Information System (INIS)

By its very nature redox potential measurement is suitable for determining the concentration ratio of a stable redox pair through its interaction with a chemically inert electrode surface but not the absolute concentration of a material. The measured redox potentials agree only rarely with those which are easily calculable theoretically. No individual defined stable redox pair is available in power station water. It is therefore not simply possible to measure definable mixed potentials more precisely. For these reasons redox potential measurement in the power station, as also with other types of water, can no longer be regarded as an indicator, by which it can be established whether oxidizing or reducing materials predominate in the water. (orig.).

UK PubMed Central (United Kingdom)

Trinitrotoluene (TNT) absorption was assessed in groups of workers at two explosives factories by measuring the urinary concentrations of dinitroaminotoluene (DNAT) metabolites. DNAT was detected in...Full Text Available

International Nuclear Information System (INIS)

English 1998 p. 124 Poland Antanasijevic, R. Vukovic, J. Novakovic, V. Tasic,

UK PubMed Central (United Kingdom)

The oxygen production of a photosynthetic gas exchanger containing Chlorella pyrenoidosa (1% packed cell volume) was measured when various concentrations of carbon dioxide were present...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The results of radon concentration measurements in the near surface air at San Nicolas Island, California, are presented for five different measurement sessions between May 1978 and July 1980. Emphasis is on the previously unreported results for January and July 1980. For six of eight days during the January session the measured radon concentration was greater than 40 picocuries per cm, corresponding to a continental air mass. Only the first day involved a maritime air mass with radon concentration less than about 6 picocuries per cm. In contrast to all the previous sessions, maritime air dominated the ten day session in July 1980, with radon concentrations generally less than about 5 picocuries per cm.

UK PubMed Central (United Kingdom)

The concentration of apolipoproteins was measured by quantitative immunoelectrophoresis in rat serum, in the lipoprotein-free ultracentrifugal fraction (density greater than 1.21) of serum, and in renal...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Concentration of an amine solution for removal of hydrogen sulfides and carbon dioxide from natural gas, is tested by carbon dioxide absorption measurement in an apparatus allowing complete reaction to give reliable results.

Energy Technology Data Exchange (ETDEWEB)

The predicted results of INDAC code were compared with measured {sup 3}H concentrations in air and pine-needle around the Wolsung site. The optimal sets of input data to INDAC were in addition selected by comparing the measured values with the predicted values of INDAC based on various conditions such as the release modes of effluents into the environment, the classification of wind classes, and the consideration of terrain. The predicted {sup 3}H concentrations in air and pine-needle were shown to have good agreement with measured values, although there are some limitations such as uncertainties in measured values, complex topology around the site, and the land-sea breeze effects. The assumption on the {sup 3}H behavior in vegetables or plants that the ratio of {sup 3}H concentration in plant water to {sup 3}H ...

CERN Document Server

We report the results of the evaluation of the ``concentration-density'' relation of galaxies in the local universe, taking advantage of the very large and homogeneous data set available from the Las Campanas Redshift Survey (Shectman et al. 1996). This data set consists of galaxies inhabiting the entire range of galactic environments, from the sparsest field to the densest clusters, thus allowing us to study environmental variations without combining multiple data sets with inhomogeneous characteristics. Concentration is quantified by the automatically-measured concentration index $C$, which is a good measure of a galaxy's bulge-to-disk ratio. The environment of the sample galaxies is characterized both by the three-space local galaxy density and by membership in groups and clusters. We find that the distribution of C in galaxy populations varies both with local density and with ...

Energy Technology Data Exchange (ETDEWEB)

Anode polarization measurement is performed in mixed solution of NaCl and NaF using SUS 304 steel to investigate whether F[sup -] promotes or inhibits pitting corrosion. Pitting corrosion does not occur in the solution of NaF only, but passive state is broken above a certain critical potential, resulting in overall dissolution. When anode polarization measurement is made in a solution of fixed concentration NaCl added with NaF, pitting corrosion is inhibited at a certain critical concentration. F[sup -] has no effect on corrosion potential in the solution up to this critical concentration. Overall dissolution occurs in the solution with higher concentration than the critical concentration, the current value at that time agrees with that in the solution of NaF alone, and no effect of Cl[sup -] is shown. The concentration ...

International Nuclear Information System (INIS)

Long term indoor radon gas measurements using a passive monitor are now being conducted in the basement HVAC machine rooms of about fifty commercial buildings, which are built in the Tokyo and Nagoya metropolitan area. Ventilation rates are also measured during the monitoring period. The earliest results show that the highest concentration was about twice of the EPA Standards and was obtained at Nagoya in autumn and no clear seasonal change was seen in radon concentration so far, and that the correlation between radon concentration and inverse number of ventilation rate was positive but not high. (orig.). (2 refs., 4 figs., 2 tabs.).

Energy Technology Data Exchange (ETDEWEB)

Infiltration of radon from the ground is usually the primary source of indoor radon pollution. A uniform method for radon risk classification of foundation soils based on soil-gas radon concentration measurements and on the determination of soil porosity, permeability and structure was proposed in 1990. Results of assessment of some areas in Czechoslovakia, containing more than 5000 radon concentration measurements, demonstrate the utility of the technique and confirm the link between geology and radon potential of the soil. (author)

International Nuclear Information System (INIS)

A method for the analysis of three-component mixtures is described. The method is used for contact-free determination of component concentration in the mixtures transported via a product duct. Formulae as an aid in choosing the gamma radiation source and estimating the efficiency of measurement are given. The errors of measurement by the method of formaline-water-carbamide mixture is 1-2 %. 9 refs.; 1 fig.

Energy Technology Data Exchange (ETDEWEB)

A versatile method for estimating the characteristics of radon transport in soil is developed. The method allows the following characteristics to be estimated: depth distribution function of the soil gas radon concentration, equilibrium radon concentration in the soil air, depth at which the radon concentration reaches its equilibrium value, radon flux density from the Earth's surface, and convective radon transport velocity. The method is based on soil gas radon concentration measurements and is appropriate in the case of relatively uniform geology. (orig.)

British Library Electronic Table of Contents (United Kingdom)

Activity concentrations of some anthropogenic radionuclides (90Sr, 137Cs, 238Pu, 239+240Pu and 241Am) have been measured in the surface of marine sediments along the Saudi coast of the Arabian (Persian) Gulf. The samples were collected at different locations and water depths. The spatial distribution of the concentrations of the measured radionuclides showed a heterogeneous pattern and is independent of location or water depth. The obtained results are discussed and some conclusions are drawn.

Energy Technology Data Exchange (ETDEWEB)

Radon concentration measurements were performed for one year in 12 different boron, chromium and coal underground mines in Western Turkey. Lucas cells and nuclear track detectors were used for the measurements of radon and its decay products. The effects of parameters, such as type of mine, gallery depth and ventilation rate, on the radon concentration in mine air were examined. The radiation exposure doses of miners due to the inhalation of radon and radon daughters were determined. Gamma survey measurements were also realized together with radon measurements and the total effective dose equivalents in mSv y{sup -1} were estimated.

International Nuclear Information System (INIS)

Beneath the harsh deserts of Saudi Arabia lie dark chambers and complex mazes filled with strange shapes and wondrous beauty. Radon concentration measurements have been carried out in the desert caves of Al-Somman Plateau in the Eastern Province of Saudi Arabia. Passive radon dosimeters, based on alpha particle etch track detectors with an inlet filter, were used in this study. A total of 59 dosimeters were placed in five caves for a period of six months. Out of 59 dosimeters, 37 could be collected for analysis. Measurements showed significant variations in radon concentrations in caves depending upon their natural ventilation. The results of the study show that the average radon concentration in the different caves ranges from 74 up to 451Bqm"-"3. The average radon concentration in four of the caves was low in the range 74-114Bqm"-"3. However, one cave showed ...

Energy Technology Data Exchange (ETDEWEB)

In Sweden there is a demand for a method of measuring radon in dwellings with high accuracy and at a low cost. A method of determining radon concentration (Bq.m/sup -3/) in dwellings has been developed at the Swedish National Testing Institute. A plastic canister containing activated charcoal has been tested in a radon chamber (volume 20 m/sup 3/) to determine the effects of relative humidity, temperature and exposure time. The activated charcoal in the canister adsorbs radon from the air surrounding the canister. The radon concentration is determined by counting the gamma rays from the decay of radon and daughters. The theory and preliminary results from calibrations and field measurements are reported.

International Nuclear Information System (INIS)

The mine dumps that arise from the gold mining operations in South Africa are a potential source of high concentrations of radon (222"Rn). Studying the diffusion of radon and the emanation from the soil will help to deduce the radon flux from these dumps to identify the problem areas for rehabilitation. This study describes measurements of the emanation coefficient and the modelling of the depth profile of the radon activity concentration, which is compared to a depth profile that was measured on such a mine dump. Emanation coefficients ranging from 0.13 to 0.39 have been obtained.

International Nuclear Information System (INIS)

A new type of passive integrating cup monitors was developed to measure indoor thoron("2"2"0Rn) and radon("2"2"2Rn) concentrations. By placing a pair of cup monitors with different size a air exchange windows in the same place during a sufficient period of time the concentrations of both gases can be assessed from the alpha track densities on the CN films of the two monitors. The lower detection limit with a 3 months measurement period is for "2"2"0Rn 26.1 Bq*m"-"3 and is for "2"2"2Rn 6.1 Bq*m"-"3. Radon-220 and "2"2"2Rn concentrations have been measured in about 20 different types of dwellings around the Nagoya area with these monitors. The results suggest that the "2"2"0Rn concentrations were rather high in traditional Japanese dwellings made of a timber frame and mud. (orig.). (4 refs., 4 figs.).

International Nuclear Information System (INIS)

Long term indoor radon gas measurements using a passive monitor were conducted in the basement rooms of five hospitals, which are built in the Tokyo metropolitan area. The ventilation rate averaged over all hospital was 12.3 air change per hour (ACH). The highest radon concentration was 56.3 Bq/m"3. The value averaged concentration over all hospital and all season was 20 Bq/m"3. But the average of the two hospitals were twice as high as those of three others. Since the total ventilation rate integrated over a day is not different much, the reason of the concentration difference is considered to be the difference in radon emission rate from concrete wall and soil of the each hospital. Though we inquired workers about 'Environmental complaints', it do not show the direct relation between radon and environmental complaints. (author)

International Nuclear Information System (INIS)

Ground water is treated in the Czech Republic so that small water tanks are built above each water source to serve the primary ground water treatment; water so pretreated is then concentrated in large basins for subsequent treatment. Some water tanks where the first contact of the ground water with air takes place were selected as sites predisposed to radon accumulation. The examination was carried out near the town of Jihlava, where the bedrock contains slightly elevated radium concentrations. The average radon concentrations lay within the region of 2-4 kBq/m"3; the instantaneous values, however, exhibited appreciable periodical variations during the day. The relatively high radon concentrations will not pose a marked hazard for the personnel because the employees only reside at the sites in question for 10 to 15 minutes within 2 days, not for the whole working day

Energy Technology Data Exchange (ETDEWEB)

Concentrations of {sup 239+240} Pu and {sup 137} Cs were measured for vertical direction and horizontal direction in seawater collected at 21 locations on the 8 directions near Wolsung nuclear power plant. The inventories of {sup 239+240} Pu and {sup 137} Cs were calculated in seawater column. The concentrations of {sup 239+240} Pu and {sup 137} Cs were in seawater in the range of 8-36 {mu}Bq/L, 2.4-4.5 mBq/L, respectively. The {sup 239+240} Pu concentration increased with depth, however, the {sup 137} Cs concentrations not greatly changed with depth above thermocline.

International Nuclear Information System (INIS)

A case-control study on lung cancer and radon exposure in dwellings has been carried out in Lazio, a high indoor radon region of Central Italy. A total of about 400 cases and 400 controls were recruited and radon concentration was measured in a total of about 1850 dwellings. In each dwelling, radon concentration measurement devices were placed in both the main bedroom and living room for two consecutive six-month periods. Each radon device, enclosed in a sealed polyethylene bag, contains two LR 115 detectors, each being covered by a thin absorber to reduce the alpha-energy within the detector sensitive range. A quality assurance program, described in this paper, was applied in order to reduce radon concentration measurement uncertainty, which have a significant impact on the results of an epidemiological study. The reported internal quality control and ...

International Nuclear Information System (INIS)

In VHTGR (Very High Temperature Gas-cooled Reactor), the radiation plays an important role in heat transfer through the cavity in RCCS (Reactor Cavity Cooling System). We performed the series of experiments to measure the emissivity using the infrared thermometer with wavelength range of 8#approx#14 #mu#m. As the first step, the transmittance of Zinc Selenide (ZnSe) window was measured to estimate the emissivity that can compensate the attenuation effect of window. The kind of gas with various concentrations in the cavity will be released during postulated accidents to the coolant type, so it is essential to estimate the effects of gas on the measurement of emissivity. In this manner we measured the emissivity with the air, the helium and the steam inside chamber. The results represent that the concentration of the air and the helium do not affect the emissivity ...

Energy Technology Data Exchange (ETDEWEB)

The results of radon concentration measurements inside of the Gabriel caves of Mexico, during three consecutive two-month periods covering almost three seasons, are reported in the present work. The radio-ecological importance of this site is related to the radon and its concentration-dynamic behavior in the cave. Further interest in radiation safety motivated this initiative since routine biological field work is done, with people spending long periods of time there. CR-39 passive nuclear track detector was chosen for this survey. Radon concentration levels decrease during the rainy season and show different values depending on the ventilation and geometeorological structure. Measured values range between 956 and 4931Bqm{sup -3}, an indication that radon doses may exceed the allowed values for workers. This project is part of a larger study of indoor radon alpha emitters in Mexican ...

British Library Electronic Table of Contents (United Kingdom)

Indoor and soil gas Radon (222Rn) concentration measurements were accomplished in two stages in Sivas, a central eastern city in Turkey. In the first stage, CR-39 passive nuclear track detectors supplied by the Turkish Atomic Energy Authority (TAEA) were placed in the selected houses throughout Sivas centrum in two seasons; summer and winter. Before the setup of detectors, a detailed questionnaire form was distributed to the inhabitants of selected houses to investigate construction parameters and properties of the houses, and living conditions of inhabitants. Detectors were collected back two months later and analysed at TAEA laboratories to obtain indoor 222Rn gas concentration values. In the second stage, soil gas 222Rn measurements were performed using an alphameter near the selected h...

International Nuclear Information System (INIS)

Solid state nuclear track detectors (SSNTD) are widely used for radon measurements and CR-39 is one of the most popular SSNTD. In this work it was determined the calibration factor for radon concentration measurements through the passive method with CR-39 detectors. The detectors were put in a proper device (an adapted Lucas cell) and exposed to the standard radon concentration through the Pylon Model RN-150 flow through radon gas source. After exposure, the detectors were etched for 5.5 hours in a KOH solution at 80 deg C in a bath at a constant temperature. The track density was read in an Axiolab-Zeiss optical microscope, with nominal magnification of X10 connected to a video camera and to a personal computer. The calibration factor was obtained through the relation between standard radon concentration, track density and exposure time. (author)

International Nuclear Information System (INIS)

Concentrations of 226Ra, 232Th, and 40K measured in bauxite waste, local building materials, and soils are presented and used in model equations to estimate the effective gamma dose-equivalent increments over background in the center of a standard-sized room in a prototype house. Calculated and measured values compare reasonably well.

International Nuclear Information System (INIS)

The barrier glow discharge between two planar electrodes, covered with dielectric, is studied under high-voltage pulsed power supply. Wide applications of such type of discharges, in particular, for ozone production, stimulated a number of investigations in this direction. In this work we investigated the dependence of ozone concentration on the duration and the rate of pulse rise of the applied voltage. The thyristor converter circuit with the shortening of input pulses on the base of the saturable throttle was used for the realization of this task. The output pulses with amplitude up to 15 kV, repetition frequency of 1 kHz, pulse duration of 0.3 #mu#s (or 7 #mu#s) and the rate of pulse rise of 0.1 #mu#s were generated with this scheme. Measurements of the ozone concentration produced in the air mixture have shown that its value increased by factor two with variation of the rate of pulse rise from 0.5 #mu#s to 0.1 #mu#s ...

International Nuclear Information System (INIS)

Investigations were made on the biodegradability and bacterial toxicity of chemicals. The intention was to obtain data necessary for estimating and judging the behaviour of these chemicals during aerobic biological waste water treatment. The course of biodegradation and toxicity with time and concentration could be measured, quantified and described. As test procedure, the respirometric dilution method was used. This method is based on a die away test with continuous measuring of the oxygen used for biochemical oxidation processes. The course of the oxygen demand with time and concentration shows the biodegradation and toxicity patterns of the tested chemical. A variety of household and industrial chemicals were investigated. One group of substances were microbiocides, some of which showed toxic effects at concentrations less than 20 mg/l while others were biodegradable even at ...

Energy Technology Data Exchange (ETDEWEB)

Diffusion of radon in a bed of activated charcoal is described by diffusion equations. An analytical solution of these equations is presented for the case of constant radon concentration in the atmosphere. The solutions are given separately for short term and long term exposure. An analytical form of the calibration constant f for long term exposure and constant radon concentration in air, was found. A numerical method and computer code based on the method of finite elements is developed for the case of variable radon concentration in air. This program simulates radon adsorption by the activated charcoal bed, enabling determination of sensitivity. The dependence of sensitivity on different parameters, such as temperature, thickness of the charcoal, etc. was studied using this program. (orig.) 10 refs.

International Nuclear Information System (INIS)

Lead lanthanum zirconate titanate (PLZT) nanopowders with chemical compositions x/65/35 PLZT (x = 6 - 10 mol%) were prepared by sol-gel method. PLZT ceramics was obtained by the conventional sintering method and utilizing the hot pressing method. The investigations of dielectric and ferroelectric measurements of as obtained PLZT ceramics have revealed the influence of lanthanum concentration on the properties of PLZT electroceramics. (author)

UK PubMed Central (United Kingdom)

The magnetic susceptibility and the density of human oxy-(HbO₂) and carbonmonoxyhemoglobin (HbCO) solutions of various concentrations have been measured at room temperature, with pure water...Full Text Available

International Nuclear Information System (INIS)

Inhalation of radon and its daughter products makes the major contribution to the total exposure of the population to natural radiations. In implementing a complex ecological survey, concentrations of radon and its daughter products were measured in different regions of Russia, namely, in the St. Petersburg Region, the Central Territories and the Altay Territory. Two suitable low price versions of the dosemeters for measuring environmental radon concentrations based on track-etch and activated-charcoal detectors were used. The radon daughter product activity and the effective dose equivalents were calculated with an equilibrium factor of 0.5 and a recommended effective dose equivalent factor of 0.061 mSv (Bq m"-"3)"-"1. Indoor measurements were taken in more than 1000 dwellings and public and industrial buildings of 21 towns and villages. The track chambers were exposed for about ...

Energy Technology Data Exchange (ETDEWEB)

The concentration of some organic acids in the atmosphere was determined using a wet effluent diffusion denuder-aerosol collector coupled with Ion Chromatography. Three organic acids and four inorganic anions were identified and quantified in the air sample, taken from the backyard of PSI. (author)

UK PubMed Central (United Kingdom)

Nutrient transport affinities of nutrient-starved microbial populations were measured as initial slopes of plots of limiting-nutrient transport rates versus extracellular limiting-nutrient concentrations....Full Text Available

Wastenet

... Radon gas concentrations are measured using instruments with calibrations traceable to the UK National Physical Laboratory and PTB, Germany. The primary facility is a 43 m3 walk-in chamber accessed by an airlock. Radon gas is maintained at a level in this chamber that is ...

UK PubMed Central (United Kingdom)

Assessment of the regulation of plant metabolism by the calcium ion requires a knowledge of its intracellular levels and dynamics. Technical problems have prevented direct measurement of the concentration...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Ferrography is a technique for isolating wear particle debris from lubricating and hydraulic oils, the presence of which carry with them a history of the wear processes in the machine. Thus, the technique has fundamental applications in machine condition monitoring and failure prevention. The wear particles are significant in the metal types that are present in the particle distribution as an indication of the wearing machine components and in the particle size distribution and morphology which indicates the severity of wear in the system. In this paper, the fundamental principles which describe the working of the ferrograph, concentrating on the working of the on-line ferrograph are discussed. The significance of equilibrium particle concentration in the oil system and its measurement using the ferrograph are also discussed.

Energy Technology Data Exchange (ETDEWEB)

The results of weekly radon concentration measurements in an office environment using a novel envelope-type radon monitor for short-term exposure periods are presented. The commercially available LR-115 damage track detectors are used and the chemically etched sheets are spark counted. The measurements were made over a period of one year. The indoor radon concentration varies from {approx} 20 Bq.m{sup -3} to {approx} 300 Bq.m{sup -3} with the average of 130, 81 and 73 Bq.m{sup -3} for three different rooms resulting in the annual dose of 4.5, 2.8 and 2.5 mSv, respectively. (author)

International Nuclear Information System (INIS)

Major contributions during this contract period have been in developing an analytical procedure for Pu measurement, and in applying the developed procedures to determining the plutonium concentration and distribution in coral from the Bikini Atoll. In conjunction with these contributions, measurements using the fission-track method have been made of the uranium distribution and concentrations in several carbonate samples from drill cores obtained from the Runit Island Enewetak Atoll. Petrographic studies on these drill core samples have been made to correlate the uranium data with the mineralogical data.

International Nuclear Information System (INIS)

Most important radionuclides naturally appearing in minerals used to form building materials are described. The frequently met ranges of concentrations of these radionuclides in the building materials composed from natural products as well as from power-plant wastes and metallurgic plant wastes are discussed and propositions concerning the limitation of presence of radioactive nuclides in the building materials are given, with special concern paid to materials for dwelling and public utility buildings. The elaborated technique of measuring potassium 40, radium 226 and thorium 228 concentrations is presented. Data on the organization of controlling-and-measuring laboratories in this field are given. (author).

British Library Electronic Table of Contents (United Kingdom)

Let Y be a nonnegative random variable with mean?? and finite positive variance ? 2, and let Y s , defined on the same space as Y, have the Y size-biased distribution, characterized by Formula Not Shown Under a variety of conditions on Y and the coupling of Y and Y s , including combinations of boundedness and monotonicity, one sided concentration of measure inequalities such as Formula Not Shown hold for some explicit A and B. The theorem is applied to the number of bulbs switched on at the terminal time in the so called lightbulb process of Rao et?al. (Sankhy? 69:137?161, 2007).

Energy Technology Data Exchange (ETDEWEB)

Radon concentration measurements in atmosphere were taken in years from 1997 to 1999 in Milan and at pre-alpine sites located north of Lombardy. In this paper the results of measuring campaigns and a comparison of radon levels observed in the hilly area north of the town and on the pre-Alps are reported. The general criteria of the measurements and the interpretative models of radon concentration are presented. The Lake Maggiore area shows evidence of a great nocturnal stability and frequent formation of Nocturnal Stable Layer. The peculiar findings in the high altitude stations confirm the use of radon as an indicator of atmospheric dispersion of pollutants in an area with complex orography. The afternoon minimum values are concordant for the different stations: this implies a remixing in afternoon hours over the whole area investigated.

Energy Technology Data Exchange (ETDEWEB)

The absorption of carbonyl sulfide in aqueous methyldiethanolamine (MDEA) was studied over a range of temperatures and MDEA concentrations. MDEA is commonly used for selective absorption of hydrogen sulfide in the presence of carbon dioxide. However, sulfur in the form of COS may also be present and it is necessary that estimates of absorption rates of this compound be made. The objective of this study is to determine the physiochemical properties needed to predict COS absorption rates in aqueous MDEA. Free gas solubility and the diffusivity of COS in MDEA solutions were measured over the temperature range 15 to 40{sup 0}C for MDEA concentrations up to 30 weight per cent using the nitrous oxide analogy method. Solubilities were measured volumetrically in an equilibrium cell and diffusivities were measured using a laminar liquid jet absorber. The kinetics of the reaction between COS ...

International Nuclear Information System (INIS)

Radon concentration measurements in atmosphere were taken in years from 1997 to 1999 in Milan and at pre-alpine sites located north of Lombardy. In this paper the results of measuring campaigns and a comparison of radon levels observed in the hilly area north of the town and on the pre-Alps are reported. The general criteria of the measurements and the interpretative models of radon concentration are presented. The Lake Maggiore area shows evidence of a great nocturnal stability and frequent formation of Nocturnal Stable Layer. The peculiar findings in the high altitude stations confirm the use of radon as an indicator of atmospheric dispersion of pollutants in an area with complex orography. The afternoon minimum values are concordant for the different stations: this implies a remixing in afternoon hours over the whole area investigated.

Energy Technology Data Exchange (ETDEWEB)

SO/sub 2/ concentrations in the Stuttgart air have been measured continuously since 1965. The two measuring points were located at the bottom of the Stuttgart city basin and 900 m east on the side of one of the surrounding hills. Long-term curves of pollutant loads have been established in consideration of meteorological parameters, as well as curves showing the average daily, weekly, and yearly pollution. The information thus gained may help to plan air pollution abatement measures in city planning.

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New York City data indicate that seasonal and annual variations in dispersion-normalized air pollutant concentrations appear to accurately reflect changes in source emission patterns. The normalized concentrations make it possible to observe the impact of regulatory changes on ambient air quality without these impacts being obscured by meteorological fluctuations. It is found that numerical modeling techniques and regression analysis can be powerful tools for extracting information from large sets of air quality data. The use of differential, as opposed to absolute, pollutant concentration values will reduce artifact correlations caused by seasonal, weekly, or daily meteorological fluctuations and will permit more accurate estimation of the regression coefficients. This technique was successfully applied to a set of daily pollution measurements whose absolute concentrations were ...

British Library Electronic Table of Contents (United Kingdom)

One hypothesis for the decline of the North American greater (Aythya marila) and lesser (A. affinis) scaup population is that contaminant burdens acquired on wintering or staging areas impair reproduction or cause lethal or sublethal health effects. Recent studies have found increased selenium (Se) concentrations in scaup but have focused on the fall and spring staging periods. From January to March 2006 and December to March 2006 and 2007, we analyzed liver tissues collected from greater scaup wintering in western Lake Ontario for 16 trace elements. We also measured Se concentrations in greater scaup blood and Dreissenid mussel tissue. Se was the only trace element that occurred at increased concentrations (>10??g/g liver dry weight) in a substantial proportion (99%) of greater scaup live...

International Nuclear Information System (INIS)

The phase separation of (water + salt + polyethylene glycol 15000) systems was studied by cloud-point measurements using the particle counting method. The effect of three kinds of sulphate salt (Na2SO4, K2SO4, (NH4)2SO4) concentration, polyethylene glycol 15000 concentration, mass ratio of polymer to salt on the cloud-point temperature of these systems have been investigated. The results obtained indicate that the cloud-point temperatures decrease linearly with increase in polyethylene glycol concentrations for different salts. Also, the cloud points decrease with an increase in mass ratio of salt to polymer.

International Nuclear Information System (INIS)

This work describes the radon in soil gas measurements performed during the last two years in cooperation between the Laboratory of Applied Nuclear Physics of the Federal University of Technology (UTFPR), the Nuclear Technology Development Center (CDTN) and the Institute of Radiation Protection and Dosimetry (IRD) from the Brazilian Nuclear Energy Commission (CNEN). Following previously concluded measurements of radon concentration in dwellings and the measurements of 222Rn activity in drinking water collected at artesian bores of Curitiba urban area, present step of activities has been dedicated to measurements of radon concentration in soil gas. Experimental setup was based on the Professional Radon Monitor (ALPHA GUARD) connected to specially developed for such measurements Soil Gas Probe through the air pump and filter system. After the ...

International Nuclear Information System (INIS)

"2"3"9 "2"4"0Pu concentrations were measured in biota from a 30-year-old contaminated floodplain forest in Tennessee. Concentration ratios relative to soil, for plutonium in litter, invertebrate cryptozoans, herbaceous ground vegetation, orthoptera and small mammals were approximately 10"-"1, 10"-"2, 10"-"3, and 10"-"4, respectively. Concentration ratios (CR) for plutonium in biota from the floodplain forest are less than CR values from other contaminated ecosystems in the USA. Presumably, this is due to humid conditions and greater rainfall which minimize resuspension as a physical transport mechanism to biota. Plutonium and radiocesium concentrations are correlated in biota from the forest at Oak Ridge and also from Mortandad Canyon in New Mexico. The cause of the covariance between concentrations of these elements is unknown. Nevertheless, the existence of ...

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The report presents details of the distributions of air pollution in the Berlin area and the developments of the past 20 years. Highly polluted areas are indicated in which air pollution reduction measures are particularly urgent. The report therefore intends not only to inform but also to point out the deficiencies of air pollution abatement measures, so that political consequences can be derived and measures can be taken. In all, data were recorded by 39 measuring stations in West Berlin, 16 in East Berlin, and 7 in Potsdam and Frankfurt/Oder. In most stations, sulphur dioxide and airborne dust were measured; 14 stations in West Berlin and one in East Berlin measured carbon monoxide and nitric oxides; 8 stations in West Berlin recorded ozone concentrations. (orig./KW).

Energy Technology Data Exchange (ETDEWEB)

Within the framework of the EFTTRA cooperation between CEA, ECN, EDF, FZK, IAM and ITU, six metallic {sup 99}Tc rods have been irradiated in the Petten HFR for 193 effective full power days. During this irradiation, more than 6% of the {sup 99}Tc has been transmuted to the stable {sup 100}Ru. At ECN, one of the six rods has been examined in the hot cell laboratory. The ruthenium concentration in the rod measured by Isotope Dilution Mass Spectrometry reaches 6.4% at 5 mm from the bottom of the rod and 6.0% at 5 mm from the top. Also the axial and radial distributions of the ruthenium have been measured by Electron Probe Micro Analysis. The ruthenium concentrations calculated by the three-dimensional Monte Carlo code KENO reach 6.1% at 5 mm from the bottom of the rod and 5.7% at 5 mm from the top. These values are in reasonable agreement with the measured ones. However, the calculated ...

Energy Technology Data Exchange (ETDEWEB)

Simulation of the skim-off method for radon measurement by activated charcoal has been carried out by the finite elements method. The variation of radon concentration with peak appearance has been simulated. The thickness of the layer of charcoal removed after exposure and the time of peak appearance have been varied. For the charcoal and canister geometry used, the best results were found when the thickness of the layer removed was 1.72 mm.

Energy Technology Data Exchange (ETDEWEB)

A novel envelope-type radon monitor has been used for short-term (as little as 1 week) radon concentration measurements in a workplace environment. The commercially available LR-115 type II damage track detector was used in this study and the chemically etched sheets were spark counted. The measurements were made over a period of 1 year in a workplace consisting of three adjacent rooms situated in the lower ground level of multistorey office building in Rome, Italy. The variations of the radon concentration are from [approx] 20 to [approx] 300 Bq m[sup -3] with averages of 130,81 and 73 Bq m[sup -3] for the three different rooms resulting in annual doses of [approx] 3.8, [approx] 2.4 and [approx] 2.2 mSv, respectively. (author) 2 figs., 9 refs.

Energy Technology Data Exchange (ETDEWEB)

This paper presents the history and objectives of the development of a standard method for the measurement of organic contaminants in biomass producer gases. Recently, a project with that title has started in the European 5{sup th} Framework Programme. The structure of this project with acronym 'Tar Protocol' is also described in this paper. The project is performed by 17 partners and continues earlier work initiated by IEA (International Energy Agency), DoE (Department of Energy) and EU (European Union) in 1998. The project aims to combine two draft Protocols that resulted from this earlier work. The Tar Protocol will be developed for accurate measurement of organic contaminants ('tars') over a large range of concentrations (1 mg/Nm{sup 3} to 100 g/Nm{sup 3}) and conditions (0 - 900 deg C; 0.9 - 60 bars). Besides, a particulate concentration will be determined too. ...

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The objectives of this study are to make a biosensor on a trial basis which can instantaneously measure the nitrogen in wastewater, and to develop a wastewater treatment system which is capable of on-line measurement and controlling. The system provides easier operational control relating to such a high efficient treatment as the removal of nitrogen content in wastewater, serving as a solution to the eutrophication problem. It can be applied also to the analysis of fertilizer components for agriculture. Ammonia oxidizing bacteria were immobilized with cellulose acetate film, which is mounted on a diaphragm type oxygen electrode to make a sensor, and its responsibility was studied. The gradient is slow in high concentration but sharp in low concentration, and it seems possible to use it for the measurement for less than 20 ppm nitrogen concentration. The ...

International Nuclear Information System (INIS)

The EUROTRAC sub-project ''Tropospheric Ozone Research'' (TOR) follows a dual strategy: - Observation of the chemical processes contributing to the oxygen balance directly in the atmosphere; - Establishment of a validated data base for model calculations. Both tasks require simultaneous measurements of a wide range of chemical and meteorological components. In the case of the investigation of the chemical processes, it is also desirable to measure the free radicals directly involved in ozone production. In the project described, a measuring station was set up. For a period of two years and a half, continuous measurements were made of ozone and its chemical precursors (NO, NO_2, NO_y, VOC, CO), as well as other photooxidants (H_2O_2 and organic hydroperoxides, organic nitrates), the photolysis frequency of NO_2, and meteorological parameters (wind, temperature, moisture, aerosols). The station was ...

Energy Technology Data Exchange (ETDEWEB)

The evaluation of radon concentration measurements in newly developing geothermal reservoirs with the objective of determining the ability of measured changes in noncondensible gas components, such as radon, to predict changes in the thermodynamic properties of the reservoir is described. This ability would be especially useful in liquid-dominated resources, where changes in steam fraction are sensitive to changes in reservoir temperature and fluid enthalpy. Radon measurements were made in samples separated by phase at the outlets of a prototype rotary separator turbine. The data were examined in relation to the thermodynamic properties of the geofluids supplied by the test well.

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The measurement of electron densities using interferometry and refraction measurements in plasmas with cross-sections where the electron density contours are concentric ellipses is examined. Transforms are found for both interferometrically deduced optical path-length differences and refraction angle data obtained from elliptical cross-section plasmas. The transformed data can be inverted to give electron densities using standard techniques developed for circular cross-section plasmas. Refraction of light in elliptical cross-section plasmas is examined using numerical ray tracing.

International Nuclear Information System (INIS)

A revision of some basic concepts related to the analysis of variance of repeated measures is presented within an ecological context topics such as the types of experiments in which the technique is applicable, the hypotheses of interest, and its preference over other traditional techniques such as regression and conventional analysis of variance, are discussed. As an example, the technique was successfully applied to an experiment carried out at Cienaga Grande de Santa Marta, Colombia, in which the concentration of cadmium #mu#g/g in leaves of the black mangrove Avicennia germinans was measured in several monitoring stations and throughout several sampling intervals representing seasons.

Science.gov (United States)

The family of natriuretic peptides consists of the atria natriuretic peptide (ANP), the cerebral natriuretic peptide (BNP), the type C natriuretic peptide (CNP) and the peptide isolated from the dendroaspis snakes' poison (DNP), whose presence in humans has not been confirmed. The physiological function of ANP is in the control of arterial blood pressure by regulation of systemic vascular resistance of blood vessels. BNP is produced as one of the factors in the acute response to inflammatory tissue damage, mainly in coronary vessels. Increased serum concentrations of natriuretic peptides have been found in stress situations, such as trauma or major surgery, systemic hypotension, and in intrinsic myocardial dysfunction. High concentrations of natriuretic peptides were observed in severe sepsis, septic shock and in multiple organ failure, probably due to increased secretion by mediators of the inflammatory process.The highest ...

International Nuclear Information System (INIS)

TRACI, a model based on the physical mechanisms governing the radon transport in unsaturated soils, has been developed to evaluate the radon flux density at Uranium Mill Tailings (UMT) covers surface. First, moisture contents in the soil, induced by weather conditions, are calculated. Then, radon concentrations in the air-filled pore space, and radon flux density at the soil surface, are deduced from a transport model which takes account for diffusion and convection in the pore space. To check the hypothesis used in TRACI and the efficiency of cover layers, an in situ study was launched in 1997 with the French uranium mining company, COGEMA. It consists of continuous measurements of moisture contents, suctions, radon concentrations at various depths inside an UMT cover, and flux density at its surface. The first analysis made on in situ observations shows that radon concentrations and flux density, ...

International Nuclear Information System (INIS)

In the Harghita volcanic range (Romania) there are many occurrences of dry CO2 emanations, called mofettes. The emanating gas with high carbon dioxide content has a proved curative effect. The gas also contains important quantities of radon. Since the mofettes are used in curative purposes in several illnesses, in most of the cases without medical supervising, has been proposed to determine the radon activity concentration in some of the most frequented mofettes from Romania. The seasonal variations have also been monitored and were calculated the effective doses received by the patients during a cure. The radon activity concentrations' levels above the mofettes indoor air range between 548 and 10 717 Bq/m3 while within the gas pools' values between 3210 and 32 781 Bq/m3 have been measured. The effective dose received by the patients during a cure is between 0.0086 and 0.16 mSv. No major seasonal variations of the radon ...

International Nuclear Information System (INIS)

High-dose ion implantation followed by solid-phase-epitaxial (SPE) growth is now a well-established technique for the production of supersaturated silicon alloys. However, these alloys also contain a high supersaturation of silicon interstitials, which give rise to transient, greatly enhanced dopant diffusion with subsequent heating. In this contribution, the authors present a study of a series of Si-Sb alloys of various concentrations which were made by Sb implantation under various conditions to deduce the origin of the observed transient diffusion. A multiple implant scheme was employed to produce samples with an approximately uniform dopant concentration from 40 to 150 nm in depth, but with the amorphous layer extending to a depth of 380 nm. By scaling the implant doses, alloys with different concentrations in the uniform region were produced, allowing an accurate measure of diffusion coefficients ...

International Nuclear Information System (INIS)

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

Energy Technology Data Exchange (ETDEWEB)

Indoor radon concentration measurements are carried out in an area close to uraniferous fluorite veins in northern Thailand. The concentrations are found to vary from season to season, having the highest value of 154 {plus minus} 51 Bq.m{sup -3} in winter and lowest value of 50 {plus minus} 12 Bq.m{sup -3} in summer. In the rainy season the concentration is 65 {plus minus} 23 Bq.m{sup -3}. There is a large discrepancy in radon concentrations from house to house in winter. These phenomena are believed to be influenced primarily by the degree of ground moisture content and air mass movement, i.e. much lower moisture content and less air movement during the winter compared to the summer and rainy season. The annual average radon concentrations in these dwellings very from 56 to 163 Bq.m{sup -3}, having an arithmetic mean of 89 {plus minus} 22 Bq.m{sup -3}, compared ...

International Nuclear Information System (INIS)

A mathematical interaction model, validated by experimental results, was developed to modeling the metal uptake by plants and induced growth decrease, by knowing metal in soils. The model relates the dynamics of the uptake of metals from soil to plants. Also, two types of relationships are tested: total and available metal content. The model successfully fitted the experimental data and made it possible to predict the threshold values of total mortality with a satisfactory approach. Data are taken from soils treated with Cd and Ni for ryegrass (Lolium perenne, L.) and oats (Avena sativa L.), respectively. Concentrations are measured in the aboveground biomass of plants. In the latter case, the concentration of metals in different parts of the plants (tillering, shooting and earing) is also modeled. At low concentrations, the effects of metals are moderate, and the dynamics appear to be linear. However, ...

International Nuclear Information System (INIS)

Some crops of important nutritive requirements have been collected from farmlands located in Bitsichi an old tin mining town in north central region of Nigeria. The food crops were analyzed in order to determine trace element concentrations level using Neutron Activation Analysis (NAA). The activity concentrations due to natural radionuclides in the food samples and soil samples collected within the root zone of the crops were also determined using gamma-ray spectrometry (GRS). The NAA results obtained showed higher concentration of Potassium among the essential elements in all the crops. Calcium concentration in both maize and Guinea corn was below detection limit and also Zn in Green beans, sweet potato and cassava. The trace elements; Sc, Hf, Sm, and Th, were below detection limit in all the crops except in Green beans. Rubidium (Rb) and lanthanum (La) were below detection limits only in Cabbage. The ...

Science.gov (United States)

The study is concerned with the Stefan problem of evaporation of a volatile component from its solution with a virtually non-volatile material. The analysis provides an analytical solution to the problem based on mass-transfer fundamentals. Results yield the evaporation rate, interfacial mole fractions, concentration profiles in the gas and liquid phases, and the location of the evaporation front. The analysis can be used to provide the binary liquid diffusion coefficient of the volatile component based on experimental data for the liquid gas interface position as a function of time. The requirements for such a measurement are discussed in terms of the volatility of the evaporating component and its initial concentration in the liquid mixture.[Figure not available: see fulltext.

Energy Technology Data Exchange (ETDEWEB)

A weak shift of the isotope concentration ratio Li{sup 6}/Li{sup 7} was measured in the coexisting phases of the miscibility gap of lithium-ammonia solutions. Li{sup 6} is slightly enriched in the concentrated metallic phase (enrichment factor {alpha} = 1.009 {+-} 0.002). This effect can be enhanced in a counter-current column to yield any desired enrichment of the two isotopes. The counter current system and its operation were tested succesfully with a sodium-potassium-ammonia solution.

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Fractal dimensional analysis was employed to obtain a quantitative measure of the morphology of polymer networks formed by UV irradiation induced polymerization of photo-reactive mesogenic monomers dissolved in a liquid crystal host medium. The fractal dimensions obtained, may be interpreted by polymer network growth following a percolation-like model for monomer concentrations well below the solubility limit. On passing the solubility limit, the polymerization process changes from a (radical chain) solution polymerization to a dispersion polymerization, with fractal dimensions decreasing and suggesting a cluster-cluster aggregation process for monomer concentrations above the solubility limit, similar to the aggregation of colloidal particles.

International Nuclear Information System (INIS)

Theoretical description of Raman scattering in disordered alloys of Ti and Zr with transition metals of groups 5-8 of the Mendeleev Periodic System in critical range of concentrations (CRC) is given. Results of Raman scattering experiment in the system Ti_1_-_xF_x at 0.0005measurements for the same samples, are presented. The order of the values of hybridization potential and energy of impurity zone, as well as their concentrational dynamics, are determined. Qualitative adequacy of the hybridization model to the alloys studied near CRC is shown.

Energy Technology Data Exchange (ETDEWEB)

The electrolyte was brought into contact with air and potassium carbonate was measured with various contact time in order to check the defect of carbon dioxide in the air on zinc-air cell. The relationship between potassium carbonate concentration in electrolyte and battery capacity was also studied. The potassium carbonate concentration in the electrolyte. The rate of carbon dioxide absorption was mainly affected by the pore size of hydrophobic membrane. Our study showed that adapting the pore of hydrophobic membrane decreased the loss of cell discharge performance due to the presence of carbon dioxide or water vapor in the atmosphere. 7 refs., 12 figs., 1 tab.

British Library Electronic Table of Contents (United Kingdom)

A large database (507 station-years) of daily suspended particulate matter (SPM) concentration and discharge data from 36 stations on river basins ranging from 600?km2 to 600,000?km2 in size (USA and Europe) was collected to assess the effects of SPM transport regime on bias and imprecision of flux estimates when using infrequent surveys and the discharge-weighted mean concentration method. By extracting individual SPM concentrations and corresponding discharge values from the database, sampling frequencies from 12 to 200 per year were simulated using Monte Carlo techniques. The resulting estimates of yearly SPM fluxes were compared to reference fluxes derived from the complete database. For each station and given frequency, bias was measured by the median of relative errors between estima...

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND AND PURPOSE It is well established that cytochrome P450 2J (CYP2J) enzymes are expressed preferentially in the heart, and that ebastine is a substrate for CYP2J, but it is not known whether ebastine is metabolized in myocardium. Therefore, we investigated its pharmacokinetics in the rat isolated perfused heart. EXPERIMENTAL APPROACH Rat isolated hearts were perfused in the recirculating mode with ebastine for 130-min. The concentrations of ebastine and its metabolites, hydroxyebastine and carebastine, were measured using liquid chromatography with a tandem mass spectrometry. The data were analysed by a compartmental model. The time course of negative inotropic response was linked to ebastine concentration to determine the concentration-effect relationship. KEY RESULTS Ebastine w...

International Nuclear Information System (INIS)

A passive dosemeter, based on a Makrofol ED track detector covered with aluminized Mylar, enclosed in diffusion chamber, has been used for radon concentration studies. Detectors have been irradiated, using a "2"4"1Am source, at different energies and fluences in order to obtain the electrochemical etching conditions that allow the optimum registration of alpha particles having energies over 3 MeV. Thirty dosemeters have been sent to the UK National Radiation Protection Board (NRPB) Radon Environmental Chamber for calibration. The sensitivity of the dosemeter has been calculated. Several dosemeters have also been exposed in houses and dwellings in the Barcelona and Madrid areas for monitoring. Values for radon concentration in the areas under study are presented. (author).

British Library Electronic Table of Contents (United Kingdom)

Previous studies indicate that the hatching success of brine shrimp (Artemia franciscana) cysts is surprisingly sensitive to ambient metal concentrations. These studies estimated median effective concentrations (EC50s) of 7, 5, and 28??g l?1 for Cd, Cu, and Zn, suggesting that the hatching end point for A. franciscana is the most sensitive tested to date for Cd and Zn in saline environments and comparable in sensitivity with the most sensitive tested to date for Cu. Furthermore, these data suggest that brine shrimp are at significant risk from Cu and Zn in Great Salt Lake (GSL), UT, where ambient concentrations as high as 10 and 14??g l?1, respectively, have been measured. Given that brine shrimp appear to be successfully reproducing in GSL, we hypothesized that these toxicity values were ...

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A multi-zone computational model in conjunction with some engine tests are used to examine the combustion process of gas fueled diesel engines common known as dual fuel engine to provide information about details of the production of exhaust emissions, especially at light load when very lean mixtures are employed. Detailed chemical reaction kinetic simulation is employed for each of these individual combustion zones so as to establish the associated temporal variations in the concentrations of reacting species right to the exhaust stage. The influence of changes in major operating and design parameters such as the concentration of the gaseous fuel in the cylinder charge, intake temperature and the size of the diesel pilot fuel employed on the production of the exhaust emissions are examined. It is demonstrated in general that any measure that tends to increase the size of the combustion regions within the overly lean ...

Energy Technology Data Exchange (ETDEWEB)

Naturally Occurring Radioactive Material (N.O.R.M.) occurs in most soil and rock, and by mining and mineral processing, some of the radionuclides are significantly enhanced. An in-situ gamma-ray detector called M.E.D.U.S.A., has been used to produce a map of relative activity concentrations in a gold mine tailings dam on the Witwatersrand in South Africa. A CsI(Na) scintillation detector is used in this system. M.E.D.U.S.A. spectra obtained from the survey were analyzed using the Full-Spectrum Analysis (F.S.A.) procedure to compute the {sup 40}K, {sup 238}U and {sup 232}Th activity concentrations. The activity concentrations are used with global positioning data (G.P.S.) to produce the concentration maps. A hyper-pure germanium gamma-ray detector (Hp Ge) was used to measure gamma-rays from the naturally occurring nuclides for soil samples taken at different points on the site to ...

Energy Technology Data Exchange (ETDEWEB)

The quantitative determination of oxide concentration by laser-induced breakdown spectroscopy is relevant in various fields of applications (e.g.: analysis of ores, concrete, slag). Calibration free laser-induced breakdown spectroscopy and the multivariate calibration are among the methods employed for quantitative concentration analysis of complex materials. We measured the intensity of neutral and ionized atomic emission lines of oxide materials by laser-induced breakdown spectroscopy and we modified the calibration free laser-induced breakdown spectroscopy method to increase the accuracy. The concentration of oxides was obtained by using stoichiometric relations. Sample materials were prepared from oxide powder (Fe{sub 2}O{sub 3}, MgO, CaO) by mixing and pressing. The concentration was 9.8-33.3 wt.% Fe{sub 2}O{sub 3}, 7.6-33.3 wt.% MgO and 33.3-81.2 wt.% CaO for different ...

Energy Technology Data Exchange (ETDEWEB)

The carbon dioxide concentration has been measured in air samples collected approximately once per week at 22 globally distributed sites during 1981-1984. All samples were analyzed on the same non-dispersive infrared analyzer apparatus. The measured concentrations are directly traceable to the WMO primary CO/sub 2/ standards. Samples which do not contain well-mixed, regionally representative air or which have been contaminated during or subsequent to sampling, have been identified. The selected data have been analyzed using an objective curve fitting method which enables improved estimation of uncertainties associated with derived parameters. The latitudinal distribution of annual mean CO/sub 2/ concentration at the network sites shows significant interannual variability possibly related to the 1982-1983 El NinoSouthern Oscillation event. No evidence was found for significant ...

International Nuclear Information System (INIS)

In October last year the first intercomparison of measurements of the soil radon concentrations between various laboratories in Slovakia was realised. The organisation of this intercomparison was conducted by the Slovak Legal Metrology in Banska Bystrica together with the Slovak National Accreditation Service in Bratislava (SNAS). The scientific guarantee of the exercise was the State metrological Centre for radon quantities, which is working at the Research base of Slovak Medical University in Bratislava. The main objective of the intercomparison was to verify the correctness of the methods for the soil radon measurements of the authorised laboratories for radon volume activities in soil air. The intercomparison (signed as SLM ILC 3/03) was performed as a 'circular' metrology comparison, in accordance with a methodical directive MSA 0117-98, published by SNAS. Six laboratories were participating on the intercomparison and ...

Energy Technology Data Exchange (ETDEWEB)

Environmental radon monitoring activities at the DOE Fernald Environmental Management Project (FEMP) have been conducted extensively since the early 1980`s. Monitoring has been conducted at ambient concentration levels (< 1 pCi/L Rn-222), inside buildings, and at significantly elevated levels (hundreds of thousands pCi/L Rn-222) within the K-65 silo that store concentrated radium bearing wastes. The purpose of this paper/presentation is to present and discuss some of the difficulties encountered/solutions (e.g. reliability, detection limits, affects of environmental factors, data transfer, etc.) that have been discovered while taking measurements using both alpha track-etch passive integrating detectors and alpha scintillation real-time detectors. A short summary and conclusion section is provided following each topic presented.

British Library Electronic Table of Contents (United Kingdom)

Fetal exposure to phthalates may be associated with adverse reproductive effects, including cryptorchidism and decreased semen quality. Information about human placental transfer is needed to qualify the hypotheses. A dual recirculating placenta perfusion system to monitor concentrations of eight phthalate monoesters in fetal and maternal perfusates was established. In addition to perfusate background measures of phthalate monoesters, the concentrations in umbilical cord plasma and placenta tissue were measured. Monomethyl phthalate (mMP), monoethyl phthalate (mEP), monobutyl phthalate (mBP), and mono (2-ethyl-hexyl) phthalate (mEHP) were detected in both maternal and fetal perfusate, demonstrating a release of compounds from tissue or blood to perfusates. The distribution of compounds bet...

Energy Technology Data Exchange (ETDEWEB)

Methods for improving the sensitivity of scintillation cells for radon concentration measurements were studied with emphasis on improving light collection efficiency. This allows the length and hence the volume of the cell to be increased. Variables studied were choice of scintillator material, its method of application and thickness, length of cell, cell material, type and configuration of reflectors, choice of photomultipliers, and factors affecting background. Response from various areas of the cell surface was studied with an alpha source and with radon filling. Coating the window with phosphor was found to be counter-productive. The optimum results obtained were with the inside of the cell (other than the window) covered with a thick layer of ZnS(Ag), or with a thick layer of reflective material coated with a thin layer of phosphor. With it, a 10 cm diameter plexiglass cell can be extended to at least 50 cm length without difficulty from ...

Energy Technology Data Exchange (ETDEWEB)

Using carbon-paste-CuFeS{sub 2} electrodes and a cyclic voltammetric technique, it was found that a large number of intermediate electrochemical oxidation reactions were associated with the dissolution of chalcopyrite in presence and absence of bacteria. The effects of concentrations of copper, ferrous and ferric ions, as well as of agitation on the peaks of cyclic voltammograms were measured. It was established that chalcopyrite oxidation was solid-state controlled as suggested by the data of chronopotentiometric and chronoamperometric measurements. The activation energy of solid state diffusion of chalcopyrite leaching was determined by the Sand's method to be {triangle}E{sub a} = 20.5 kJ. The leaching mechanism is discussed in terms of solid-state properties (energy bonding) of the n-type semiconductor chalcopyrite and energy density states of redox systems of acidic bacterial leach media. A generalized model ...

Energy Technology Data Exchange (ETDEWEB)

Measurements of local mass fluxes of liquid, local number fluxes of the drop and local drop size distributions at various locations in the test column were made for wide ranges of liquid flow rates and gas flow rates. An empirical correlation for the volume mean diameter of the drop at the nozzle exit was proposed. Measurements of the rates of absorption of carbon dioxide from carbon dioxide-air mixtures with water sprays (physical absorption) and aqueous sodium hydroxide sprays (chemical absorption) were made for wide range so fluid flow rates, feed gas concentrations, and initial alkali concentrations. The observed dimensionless rates of absorption were compared with the theoretical values by assuming penetration model with second-order irreversible reaction. 11 refs., 7 figs.

Energy Technology Data Exchange (ETDEWEB)

Region Lombardia has carried out a radon gas monitoring survey on its territory to localize radon prone areas as by law 241/00 enacted. To plan the survey, the Lombardia territory has been divided into two different types according to the morphology as well as the presence of a substratum of rock. The area with hills and mountains has been investigated with more attention compared to the plain because we can assume higher variability in radon concentration distribution due to the geological and morphological characteristics. The territory subdivision was based on the standard grid.. of the techniregional cartography (8 x 5 km). To perform radon indoor concentration measurements about 3600 measuring points were selected. They are located at the ground floor of buildings with the characteristics to ensure the tests are representative and comparable. It has also been taken into account evaluations done ...

International Nuclear Information System (INIS)

A miniature device is described for measuring integral potential alpha energy concentration of radon daughter products (Csub(Rn)) for personnel and stationary dosimetry. The measuring apparatus consists of an air sampler, filters and TLD detectors. CaSO_4:Dy-teflon pellets were used as the detectors which registrate #gamma# radiation as well. The TLD-effect dependence on the potential alpha energy, as well as the fading of the detectors at 20-60 deg C after 170 hrs operation are presentd. The fading up to 40 deg C has been found to be negligible. The dosimeter may be used to measure Csub(Rh) starting with the 10"5 MeVxh/1 threshold, the accuracy being not worse than +-30%.

International Nuclear Information System (INIS)

Researchers at the Laboratory of Nuclear Microanalysis in Besancon (France) are developing and improving radon measurements in order to detect and analyse, more precisely radon emanation anomalies in both fields of Earth Sciences and Radioprotection. In order to characterize radon emanation, two complementary techniques are developed; continuous measurement through a portable proportional counter and passive measurements by nuclear track detectors for both fieldwork and laboratory analysis. A mathematical model is being devised to interpret the nuclear track detector response. This model is performed according to the device characteristics: type of detectors, shape and size of cells and whether a membrane is used or not. In addition to the theoritical study, experimental radon concentration measurements will be reported. (author).

International Nuclear Information System (INIS)

Ozone production by synchrotron radiation as a function of power density in air was investigated using a white beam at the BNL National Synchrotron Light Source (NSLS) x-ray ring. Power densities were calculated from the energy spectrum at 2.52 GeV. Ozone concentrations in small beam pipes were measured for power densities between I = 10"1"2 and 10"1"5 eV . cm"-"3 . sec"-"1. The measured ozone half-life was 37 +- 2 min. The measured G-value was 2.69 +- 0.14 mol/100 eV and the ozone destruction factor k was less than 7 x 10"-"1"9 cm"3 . eV"-"1. The random uncertainties stated are approximately one standard error. The large departure of the values for G and k from previous values suggest that some undiscovered systematic error may exist in the experiment. Ozone concentration in excess of the 0.1 ppM ACGIH TLV can be generated in the experimental hutches but can readily be controlled. ...

International Nuclear Information System (INIS)

A combination of measuring instruments, consisting of a Beta-Sedimeter and a radionuclide X-ray fluorescence instrument, is described. With the Beta-Sedimeter the C-14-radiation is measured. Through direct irradiation with photons of a Pu238-source in an ancillary irradiation chamber and energy dispersing measurement of the K- and L-radiation resp. of the excited heavy metals with the aid of a Si(Li)-semiconductor detector and a 4-channel analyzer the heavy metal concentrations of the heavy metals Zn, Cr, Ni and Pb are determined. For the determination of cadmium the indirect excitation with Am-241 and Dy-targets is described. The system produces records and operates fully automatically in a step-by-step mode with a testing cycle of 45 minutes. In connection with the process monitoring of the wastewater from a zinc plating plant during a period of 8 months the concentration of the ...

International Nuclear Information System (INIS)

Dysprosium ion doped fluorophosphate glasses with compositions of PKMAFDy: (56-x/2) P2O5+17K2O+8Al2O3+(15-x/2)MgO+4AlF3+xDy2O3 (x=0.01, 0.05, 0.1, 1.0 and 2.0 mol%) have been prepared by melt quenching technique and are characterized by optical absorption, emission spectra and fluorescence lifetime measurements. The observed bands in the absorption spectrum are analysed by using free-ion Hamiltonian (HFI) model. The Judd-Ofelt (JO) analysis has been performed and the intensity parameters (??, ?=2, 4, 6) have been evaluated that are used to predict radiative properties. From emission spectra, the effective bandwidth (??eff) and the stimulated emission cross-section (?(?p)) were evaluated. The fluorescence decay from the 4F9/2 level of Dy3+ ions have been measured by monitoring the intense 4F9/2#->#6H13/2 transition (573 nm). The lifetimes (?) are found to decrease with increasing concentration due to ...

Energy Technology Data Exchange (ETDEWEB)

The susceptibility to intergranular corrosion of different heats of Alloy 800 was evaluated by three different methods: the ASTM A 262 Practice E (or modified Strauss test), the Electrochemical Potentiokinetic Reactivation method, and by magnetic-susceptibility measurements. Reasonably good agreement was found between the sensitization areas as defined by the three methods in the TTS diagrams. In some cases the area defined by the Strauss test was slightly smaller than that determined by the other two tests. The differences might be explained by the fact that the methods present different sensitivities to the chromium concentration at the grain boundaries. 27 references, 11 figures, 3 tables.

Energy Technology Data Exchange (ETDEWEB)

Photochemical ozone production is observed in March-September. Highest ozone concentrations and production efficiencies are observed in spring in the northern parts and in summer in the southern parts of the country. VOC concentrations are relatively low compared to continental areas in general. During the growing season a substantial part of the total reactive mass of VOCs is of biogenic origin. Large forest areas absorb ozone substantially, decreasing the ambient ozone concentrations in central and northern parts of Finland where long-range transport of ozone is relatively important compared to local production. The aim of the work conducted at Finnish Meteorological Institute has been to characterise concentrations of photochemically active species in the boundary layer and their photochemical formation and deposition including the effects on vegetation. Also interactions between the boundary layer ...

Energy Technology Data Exchange (ETDEWEB)

The effect of concentration on the corrosion behavior of Mg-based alloy AZ91D was investigated in ethylene glycol-water solutions using electrochemical techniques i.e. potentiodynamic polarization, electrochemical impedance measurements (EIS) and surface examination via scanning electron microscope (SEM) technique. This can provide a basis for developing new coolants for magnesium alloy engine blocks. Corrosion behavior of AZ91D alloy by coolant is important in the automotive industry. It was found that the corrosion rate of AZ91D alloy decreased with increasing concentration of ethylene glycol. For AZ91D alloy in chloride >0.05 M or fluoride <0.05 M containing 30% ethylene glycol solution, they are more corrosive than the blank (30% ethylene glycol-70% water). However, at concentrations <0.05 for chloride or >0.05 M for fluoride containing ethylene glycol solution, some ...

Energy Technology Data Exchange (ETDEWEB)

Biomimetic vesicle media which can selectivity extract and concentrate heavy metals (e.g., Pb{sup 2+}) from dilute solutions of 5 ppm and less have been prepared. At a concentration of only 1% 2/v, these non-covalently assembled, unilamellar, surfactant vesicles provide approximately 1,000m{sup 2} of exposed membrane surface area per liter of suspension which gives rise to very rapid rates of metal ion extraction. To facilitate the selective transport of heavy metal ions through the ion impermeable vesicle wall, the vesicles are doped with lipophilic ionophores, both natural and synthetic. In addition, the metal chelating agent, nitrolotriacetate, is encapsulated in the aqueous vesicle core to provide the driving force for metal ion uptake and concentration. Concentration factors in excess of 1000 fold have been observed. Metal-sorbing surfactant vesicles measuring approximately 100 ...

Energy Technology Data Exchange (ETDEWEB)

The Catalagzi Thermal Power Plant (CTPP) is located at nearly 13 km North-east of Zonguldak city, which is located at the West Black Sea coast in Turkey. The middling products with high ash content of bituminous coals are used in this plant. Seasonal radon concentration measurements have been carried out by using CR-39 plastic track detectors in and around the CTPP. The annual average radon concentration has been found to vary from a minimum of 39.8 {+-} 28.9 Bq m{sup -3}) in the ash area to a maximum of about to 75.0 {+-} 15.7 Bq m{sup -3} in the service building of the power plant. The annual average radon concentration in the dwellings of the thermal power plant colony of the plant is 71.0 {+-} 33.4 Bq m{sup -3}. The effective dose has been found to vary from 0.38 to 0.71 mSv y{sup -1} with a mean value of 0.56 mSv y{sup -1}, which is lower than the effective dose values 3-10 mSv given as the range ...

International Nuclear Information System (INIS)

"7Be produced by the interaction of cosmic rays with oxygen and nitrogen, predominantly in the stratosphere, has been used to identify and measure stratospheric ozone at the ground level. Simultaneous measurements at Whiteface Mountain, New York, in July 1975 show that the maximum "7Be concentrations are accompanied by increased ozone concentrations. Peaks in "7Be concentrations occurred on July 5-6, 11-12, 16-17, 23, and 27. Ozone peaks were observed on July 7-9, 11, 18, 24, and 27. Isentropic trajectory calculations also showed that the trajectories reaching Whiteface Mountain on July 11-12, 15-16, 23, and 27 had stratospheric origin. One-day delay in ozone peaks on July 7-9, 18, and 24 is attributed to increased tropospheric ozone production. The observed relationship between "7Be and ozone is used to deduce an upper limit of 37 ppb stratospheric ozone at Whiteface Mountain ...

Energy Technology Data Exchange (ETDEWEB)

For the inventory of water tritium concentration in the Manche department, it is the complementarity that animated the work opened during year 2001. To answer to a commune sensitivity such water quality, particularly drinking water at tap, the A.C.R.O. laboratory brought its know how to make and its technical means in the area of tritium analysis and the general council brought its know how to make and its logistics means in matter of sanitary control. This collaboration has allowed to supply an indication on the tritium content of the distribution waters of thirty of the most important cities of the department. Then, it allowed to inform on the radiological situation (in relation with the tritium presence) of coast waters and principal rivers waters. More than 160 controls have been realised between the months of march 2001 and february 2002. Only the tritium under the shape of tritiated water has been measured. The ...

Energy Technology Data Exchange (ETDEWEB)

A test methodology for measuring temperature, impedance, pH, and electrochemical potential distributions within a sludge-packed tube support plate crevice in a laboratory test is described. The method successfully showed that there were large concentration gradients between the tube and tube support plate sides of the crevice. The testing also showed that strong bases concentrated more effectively than strong acids, and that the crevice pH, when exposed to seawater-based solutions, increased with increasing superheat and decreasing bulk concentration. The large variations in the crevice chemistry observed under heat transfer were eliminated upon shutdown. These new test data suggest that it might be beneficial to evaluate the variation in the extent of stress corrosion cracking with tube support plate elevation found in some steam generators in light of local chemistry changes, as well as the variation ...

Energy Technology Data Exchange (ETDEWEB)

The US Department of Energy (DOE) Office of Remedial Action and Waste Technology established the Technical Measurements Center (TMC) at the DOE Grand Junction Projects Office (GJPO) in Grand Junction, Colorado, to standardize, calibrate, and compare measurements made in support of DOE remedial action programs. Outdoor radon concentration measurements were made by the TMC in Shiprock, New Mexico, to compare two different methods of measuring radon in an attempt to determine the feasibility of using passive alpha-track detectors to assess the adequacy of remedial action undertaken at the Shiprock uranium mill tailings pile. The results of the first three quarters of monitoring have been detailed in previous reports. An analysis of the data from the fourth quarter of monitoring at Shiprock reveals a somewhat poorer correlation between the two sets of measurements ...

Energy Technology Data Exchange (ETDEWEB)

The report shows that in Europe mountain regions, coastal zones, wetlands and the Mediterranean region are particularly vulnerable to climate change. Although there could be some positive effects, many impacts are likely to be adverse. Existing adaptive measures are concentrated in flood defence, so there is considerable scope for adaptation planning and implementation in other areas, such as public health, water resources and management of ecosystems. (au)

International Nuclear Information System (INIS)

Practical procedures were developed for large-scale microbial decontamination of dry egg powder and gelatine with gamma radiation ("6"0Co). The formation and lifes of free organic radicals in these materials were examined by ESR measurements of powder samples. The concentration of these radicals was studied in dependence on the time of storage. Secondary oxidation of egg fats by air oxygen was investigated. Sensoric tests of irradiated gelatine, both in powder and hydrogel form, were performed. (author). 4 figs., 2 tabs., 2 refs.

UK PubMed Central (United Kingdom)

An assay method is described for measurement of absolute concentrations of the molybdenum cofactor, based on complementation of the defective nitrate reductase ('apo nitrate reductase') in extracts...Full Text Available

International Nuclear Information System (INIS)

Nitrite was measured in atmospheric liquid phase samples between 1998 and 2005 to investigate the heterogeneous formation of nitrous acid in the lower atmosphere, as well as to assess the quality of water recovered from dew. The samples were collected during ground-based cloud field experiments at different German mountain sites (Brocken, Schmucke, and Hohenpeissenberg) and at a site south of the Bordeaux urban area (France). Concentrations found in Bordeaux dew samples (up to 2800 ?gl-1) are comparable to those found elsewhere in urban fog and dew water and considerably higher than those detected in cloud water or rain. Particulate nitrite (and nitrate) as well as HNO2 (HNO3) data in air masses from a foothill site of Mt. Schmucke, before involved in cloud processing, are also presented. In clouds at Mt. Brocken, both the interstitial HNO2 gas and the aqueous phase nitrite concentration have been ...

International Nuclear Information System (INIS)

The study by impedance and photoelectrochemical measurements of passive films formed on an AISI 304 type stainless steel shows that important parameters of the electronic structure of these films are modified under #alpha# irradiation, namely: width of the space charge region, donors concentration and diffusion length for minority carriers. The consequences of #alpha# irradiation on localized corrosion processes are discussed.

International Nuclear Information System (INIS)

Heavy metals (Pb, Cd, Mn, Cu, Zn, Fe) were determined in surface waters in the surroundings of the depositories of the mining shrubs in the region of Banska Stiavnica (SR) by radionuclide X-ray fluorescence analysis. Allowed concentrations of the determined metals are exceeded numerously (multiplicity in some cases was 10"3-10"6). (author).

UK PubMed Central (United Kingdom)

Urine is a potential source of diagnostic biomarkers for detection of diseases, and is a very attractive means of non-invasive biospecimen collection. Nonetheless, proteomic measurement in urine...Full Text Available

International Nuclear Information System (INIS)

We studied the solvent extraction behavior of astatine and found the anomalous behavior of this element similar to radioiodine. Astatine was extracted into CS_2 from acidic solution over a wide range of carrier iodine concentration. The distribution ratios of astatine were determined by measuring the #gamma#-ray from 210 At with a NaI(Tl) detector. A drastic change was observed around at 10"-"4 mol/l as in the case of 131 l. This tendency is well explained by the kinematics of the chemical reactions concerned. (author).

Energy Technology Data Exchange (ETDEWEB)

The first radon soil gas survey in Serbia, using passive detectors (SSNTD, CR-39), was carried out in June 2005 at field sites in Niska Banja town. The aim of the survey was to identify risk zones characterised by high levels of this radioactive gas. Radon measurements were made at the depth of 50 cm, in the ground according to a systematic grid pattern. Furthermore, at all 48 measurement points, the surface gamma dose rates in the air was also measured at the same locations and soil samples were collected for gamma spectrometric analysis for the radionuclides {sup 226}Ra, {sup 228}Th and {sup 40}K. Radon concentrations were found to range from 1270 to 155000Bqm{sup -3} with an average of 33765Bqm{sup -3} and a median value of 12626Bqm{sup -3}. The geometrical mean value and geometrical standard deviation were calculated as 16160Bqm{sup -3} and 3.5Bqm{sup -3}, respectively. Gamma dose rate varies from ...

Energy Technology Data Exchange (ETDEWEB)

Experiments with fresh PWR fuel assemblies were performed to assess the {sup 252}Cf-source-driven frequency analysis method for measuring the subcriticality of spent fuel. The measurements at the Babcox and Wilcox Critical Experiments Facility mocked up between 17x17 fuel pins (single assembly) and a full array of 4961 fuel pins (about 17 fuel assemblies) in borated water with a fixed B concentration. For the full array, the B content of the water was varied from 1511 at delayed criticality to 4303 ppM. Measurements were done for various source-detector-fuel pin configurations; they showed high sensitivity of frequency analysis parameters to B content and fissile mass. Parameters such as auto and cross power spectral densities can be calculated directly by a more general model of the Monte Carlo code (MCNP-DSP). Calculation-measurement comparisons are presented. This model permits ...

International Nuclear Information System (INIS)

The aim of this study is to clarify the radon behavior in the soil at the waste rock yards of uranium mine. We have developed an apparatus for measuring radon diffusion coefficient in soil under the control of soil temperature. The radon diffusion coefficients changed suddenly around the soil temperature of 0degC. The radon diffusion coefficients in dry soil have little temperature dependency, and were comparable coefficients obtained by empirical formula of Rogers and Nielson. To study the restraint effect of radon exhalation by covering with bentonite on soil, we carried out the measurements and the calculations by using one-dimensional transport model of atmosphere and soil. The decrease of radon exhalation rate was 2.9 Bq m"-"2s"-"1 when soil covered with the bentonite of 5 cm thick. The radon concentrations in snow cover and the radon flux from the snow surface were measured at the waste rock yard ...

Energy Technology Data Exchange (ETDEWEB)

Apart from presenting the marginal legal conditions the research program contains a brief description of current pollution abatement measures, representative heating systems and individually suitable pollution abatement technologies and an account of the determination of the concentration of major pollutants. The comparative evaluation of heating systems assesses their environmental effects, i.e. air pollution caused by heating systems. The determination of the costs of available heat is followed by an overall evaluation of the results obtained with special regard to the costs involved by pollution abatement measures.

Energy Technology Data Exchange (ETDEWEB)

Experiments were performed to measure the transfer of trichloroethylene (TCE), a volatile organic compound (VOC), from tap water in showers to indoor air. In these experiments, the loss of TCE from tap water in the shower is based on the difference between influent and effluent concentrations.We have developed and previously published a three-compartment model, which we use to simulate the 24-h concentration history of VOCs in the shower, bathroom, and remaining household volumes resulting from the use of contaminated tap water. An important input to this model is the transfer efficiency of the VOC from water to air. The experiments reveal that the transfer efficiency of TCE from shower water to air has an arithmetic mean value of 51 percent and an arithmetic standard deviation of 9 percent. Analysis of the results shows that there is no statistically significant difference between the transfer efficiency ...

Energy Technology Data Exchange (ETDEWEB)

Stripping Voltammetry (SV) at microelectrodes has gained increased interest in the analysis of aqueous solutions due to its ability to analyze low concentrations (ppb) of electroactive metallic species in solution. Existing integrated circuit (IC) technology allows the inexpensive fabrication of microelectrodes with dimensions on the order of microns and with a high degree of uniformity and reproducibility. Additional circuitry, both multiplexing and signal conditioning, can be placed directly onto the sensor offering increased sensitivity and flexibility. Multi-element electrochemical sensors containing arrays of Pt, Au, and Ag electrodes and capable of individual measurement through built-in multiplexing or simultaneous measurement at the appropriate potential ranges for each individual electrode were fabricated using existing 2 micron IC technology. Results of simultaneous measurements of low ...

Energy Technology Data Exchange (ETDEWEB)

Radon concentrations in homes have been shown to vary considerably with season. It is important to account for this by applying a correction factor to any home radon measurement of less than one year. To date, Irish radon measurement services have used correction factors based on data derived for the UK in the 1980s. In the absence of similar data for Ireland at the time, these were considered suitable for use due to the similarities between the climates, house types and lifestyles in the two countries. In order to better estimate the long-term radon concentration, measurements from 5640 Irish homes were used to derive a set of correction factors specifically for Ireland. These were generated by means of Fourier decomposition analysis and the new correction factors compared, using 95% confidence intervals, to those derived for the UK using the same analysis and to those currently in ...

Energy Technology Data Exchange (ETDEWEB)

Here we report a new method for measuring the heterogeneous chemistry of submicron organic aerosol particles using a continuous flow stirred tank reactor. This approach is designed to quantify the real time heterogeneous kinetics, using a relative rate method, under conditions of low oxidant concentration and long reaction times that more closely mimic the real atmosphere. A general analytical expression, which couples the aerosol chemistry with the flow dynamics in the chamber is developed and applied to the heterogeneous oxidation of squalane particles by hydroxyl radicals (OH) in the presence of O2. The particle phase reaction is monitored via photoionization aerosol mass spectrometry and yields a reactive uptake coefficient of 0.51+-0.10, using OH concentrations of 1-7x108 molec cdot cm-3 and reaction times of 1.5+-3 hours. This uptake coefficient is larger than that found for the reaction carried out under high OH ...

Energy Technology Data Exchange (ETDEWEB)

Tc-MDP 10mCi was intravenously given preoperatively to 20 patients with primary bone tumors and 1 with a metastatic bone tumor. Preoperative and postoperative scintigraphs of resected tumor and scintigraphs of sliced tumor were compared. Tissue fragments were collected from the sliced tumor, and RI measured to compare concentration rates at different areas. Histological investigations were also done. Localization of Tc-MDP was increased at sites of tumorous bone formation, of reactive bone formation at tumor edges, and of cartilage calcification, with little concentration at tumor cells or necrotic tissue. VX/sub 2/ carcinoma was transplanted into the rabbit tibia, Tc-MDP was intravenously injected when bone destruction was radiologically evident, and investigations were done as in the clinical cases. In experimental bone tumor, increased uptake localization of Tc-MDP was much the same as in clinical cases. Tetracycline was ...

Science.gov (United States)

Elastically deforming thin glass (thickness = 0.13 to 0.80 mm) provides an alternate method of forming a curved glass reflector which can eliminate some of the disadvantages of thicker glass. A concept is described where silvered thin glass is bonded to a steel backing to form a laminate with a reflectance greater than 93%. Subsequent bending of the flat reflector laminate to a concentrating profile produces compressive stresses throughout the glass if the laminate is properly designed. These compressive stresses enhance fracture resistance and the lamination provides protection for the silver. The design of the laminate is outlined for 0.25 and 0.51 mm thickness glass and fabrication procedures are discussed. Thermal/humidity cycling, hail impact, bond strength measurements and reflectance results are presented which demonstrate the performance capabilities of this reflector laminate concept.

International Nuclear Information System (INIS)

The partial pressures of the components (ThCl_4, MCl and MThCl_5) in the saturated vapours of ThCl_4 solutions in molten LiCl, NaCl, KCl, RbCl and CsCl are determined as a function of temperature (900 to 1200 K) and ThCl_4 concentration (2 to 50 mol% ThCl_4) by dynamic method. Thorium tetrachloride volatility is shown to exceed that of alkali chloride from the melts containing less than 98 LiCl or NaCl, 83 KCl, 67 RbCl and 48 mol% CsCl. From experimental observations the decomposition potential of the electrolytes under investigation was estimated in temperature and concentration ranges of our measurements. Under otherwise equal conditions, it increases in the series of alkali chlorides from LiCl to CsCl. (author).

British Library Electronic Table of Contents (United Kingdom)

The characteristics of aerosol generation were studied experimentally in an ammonia-based wet flue gas desulfurization process. Particle size distributions and concentrations, morphologies and compositions before and after desulfurization were measured using an electrical low pressure impactor and scanning electron microscopy, respectively. The results show that aerosols can be generated between ammonia and sulfur dioxide resulting in gas-phase reaction and the aerosol concentration at the outlet of scrubber is significantly higher than at the inlet. Before desulfurization the particles are primarily silica-alumina minerals including O, Al, Si and C, while after ammonia-based desulfurization aerosol particles have smooth surfaces with regular structures, such as cubic and prismatic crystal...

British Library Electronic Table of Contents (United Kingdom)

The effect of phosphonate anion (PHOS) on the corrosion of ordinary steel in simulated cooling water has been studied using weight loss, polarization curves and electrochemical impedance spectroscopy measurements. PHOS was studied in the concentration range from 7.5x10^-^5 to 10^-^3M. The results obtained reveal that PHOS perform excellently as corrosion inhibitor for ordinary steel in simulated cooling water. The inhibition efficiency of PHOS was increased with increasing both its concentration and water circulation velocity. These two factors seem to promote the adsorption of phosphorus and oxygen ions on the metal surface, leading to the formation of a protective layer with a greater charge transfer resistance and lower permeability. The inhibition efficiency decreased slightly with tem...

British Library Electronic Table of Contents (United Kingdom)

Polycrystalline ZnO doped with Mn (5 and 10at%) was prepared by the co-precipitation method. The effect of Mn doping on the photocatalytic, antibacterial activities and the influence of doping concentration on structural, optical properties of nanoparticles were studied. Structural and optical properties of the particles elucidated that the Mn2+ ions have substituted the Zn2+ ions without changing the Wurtzite structure of ZnO. The optical spectra showed a blue shift in the absorbance spectrum with increasing dopant concentration. The photocatalytic activities of ZnO powders were evaluated by measuring the degradation of methylene blue (MB) in water under the UV region. It was found that undoped ZnO bleaches MB much faster than manganese doped ZnO upon its exposure to the U...

Energy Technology Data Exchange (ETDEWEB)

The development of solid state chemical sensors, and more specifically of gas sensors, is carried out with great strength in the present time since the environmental pollution and the security in work and domestic ambient are problems of great interest and social impact. The main fields of application, are: automobile, domestic sensors, control of industrial process, bio medicine, environment. These chemical sensors are experimenting a great advance because of the advantages they offer, as low cost, simple operation, possibility of measure continuous and ''In situ'' and small size, in contrast with analytical techniques that need complex instrumentation and large size equipments. In the present work, a sensor for CO detecting concentrations as low as 50 p.p.m., is studied showing great interest since this gas is highly toxic even to such a low concentration. (Author)

Energy Technology Data Exchange (ETDEWEB)

The radiation control carried out in Atomic Energy Research Institute, Kinki University, for the reactor installation and the tracer/accelerator facilities from April, 1981, to March, 1982, is described. The reactor was operated for total 1057.1 hours at the maximum heat output of 1 W. The persons subject to radiation protection as of April, 1981, were 126 persons in all, including 23 in radiation work and 11 in X-ray work, etc. The contents of this report are as follows: personnel monitoring (health examination, the control of individual exposure dose); laboratory monitoring (the measurement of area dose rate, radioactive concentration in air and water, and surface contamination density); field monitoring (environmental ..gamma..-ray dose rate, radioactive concentration in environmental samples); the use of unsealed radioisotopes, etc.

Energy Technology Data Exchange (ETDEWEB)

This paper reports the chemical compositions of chicken-blood stone Ji Xue Shi measured by Proton Induced X-ray Emission (PIXE). The experimental result show that for the red portion of chicken-blood stone, the concentration of Hg is as high as 20 wt%, and the concentration of S can be above 10 wt%. For the non-red portion the main chemical compositions are Al{sub 2}O{sub 3} and SiO{sub 2}. The obtained chemical compositions are close to those of kaolinite for Balin chicken-blood stone, and of pyrophyllite for Changhua chicken-blood stone, respectively. So far many Changhua chicken-blood stones and Balin chicken-blood stones were found in China, the PIXE method can be used to explore the provenance of available chicken-blood stones. (author)

Energy Technology Data Exchange (ETDEWEB)

Certain fluorocarbons, such as difluorodichloromethane (FC 12), depress the cardiovascular system by diminution of all the transmembrane ionic conductances in cardiac tissues. Does FC 12 also inhibit active transport and thus enzymatic activity and cellular energy. We measured phosphocreatine (PC), adenosine triphosphate (ATP) and cyclic adenosine monophosphate (AMPc) in rat hearts. Rats were randomly divided into 4 groups; 2 control groups: one breathing a mixture of oxygen (21%) and nitrogen (79%) (group C) and the other breathing the same mixture but simultaneously perfused with 1 microgram/kg/min. epinephrine (groupe E-C); 2 trial groups T and E-T where nitrogen was replaced by FC 12. The maximal FC 12 concentration of 720 micrograms/ml in arterial blood produced no significant difference in the concentrations of these three metabolites compared with controls.

Energy Technology Data Exchange (ETDEWEB)

The effects of orthovanadate on the uptake of sucrose by Ricinus cotyledons and on sucrose-coupled proton influx were measured in order to gain insight into the relationship to the plasma membrane proton pump. Vanadate had no effect on short-term sucrose uptake. In long-term experiments (> 30 min) sucrose uptake was progressively inhibited, but only at high external sucrose concentrations. Vanadate did not affect proton efflux pumping in the absence of sucrose and neither did it change the initial rate of sucrose-coupled proton influx. However, it enhanced the maximal level of sucrose-induced alkalization of the medium at all sucrose concentrations tested. This is interpreted as an inhibiting effect of vanadate on the proton pump that recycles protons during sucrose-proton cotransport. The sensitivity towards vanadate indicates that this proton pump is an ATPase. A second proton-translocating system, that is insensitive ...

Energy Technology Data Exchange (ETDEWEB)

Forensic signatures are present in any Pu sample that can determine the sample`s origin: isotopic ratio of Pu, progeny species that grow into the sample, and contaminant species left over from incomplete purification of the Pu in fuel reprocessing. In the context of intelligence information, this can result in attribution of responsibility for the product of clandestine proliferant operations or material smuggled from existing stockpiles. A list of signature elements and what can be determined from them have been developed. Work needs to be done in converting concentrations of signature species into a quantitative forensic analysis, particularly in regard to reactor performance, but this should require only a small effort. A radiochemical analysis scheme has been developed for measuring these nuclides; more work is needed, particularly for determining fission product concentrations. A sample of Pu metal has been analyzed ...

British Library Electronic Table of Contents (United Kingdom)

World demand for rare-earth elements and the metal yttrium?which are crucial for novel electronic equipment and green-energy technologies?is increasing rapidly. Several types of seafloor sediment harbour high concentrations of these elements. However, seafloor sediments have not been regarded as a rare-earth element and yttrium resource, because data on the spatial distribution of these deposits are insufficient. Here, we report measurements of the elemental composition of over 2,000 seafloor sediments, sampled at depth intervals of around one metre, at 78 sites that cover a large part of the Pacific Ocean. We show that deep-sea mud contains high concentrations of rare-earth elements and yttrium at numerous sites throughout the eastern South and central North Pacific. We estimate that an a...

British Library Electronic Table of Contents (United Kingdom)

Carbon monoxide (CO) and carbon dioxide (CO2) emissions during a spontaneous heating event in a coal mine are important gases to monitor for detecting the spontaneous heating at an early stage. However, in underground coal mines, the CO and CO2 concentrations and their related fire ratios may be affected by mine ventilation. In this study, CO and CO2 emissions from spontaneous heating of a U.S. coal sample were evaluated in an isothermal oven under different airflow ventilation rates ranging from 100 to 500cm^3/min. Laboratory experiments were conducted at oven temperatures of 70, 90, and 100^oC. The temperature at the center of the coal sample was continually monitored, while the CO, CO2, and oxygen (O2) concentrations of the exit gas were continually measured. The results indicate that C...

Energy Technology Data Exchange (ETDEWEB)

Co-combustion tests for recycled fuels and peat were made at a 15 kW fluidized bed reactor at VTT Energy in Jyvaeskylae. Peat was used as reference fuel. 25 tests in total were performed during 1994 - 1996. A part of the peat energy was substituted by coal in five tests, in order to change the sulphur/chlorine ratio of the fuel mixture. Fuel mixtures (25% recycled fuel and 75% peat, at energy ratio) were pelletized in order to get homogeneous fuel mixtures. The tests in the year 1994 were air staging experiments (with and without tertiary air). All test were performed with air staging in the years 1995 and 1996. The aim of the research was to determine whether the co-combustion of waste materials will cause additional emission problems, as compared to combustible emissions from conventional air-staged fluidized bed combustion. Further, the aim was to study which large-volume components can be burned safely. One aim was to study the influence of fuel properties and combustion conditions ...

Science.gov (United States)

Variations in skin perfusion are easily detected by laser speckle contrast maps, but a robust interpretation of the information has been lacking. We show that multiple-exposure laser speckle methods produce the same spectral information as laser Doppler methods when applied to targets with embedded moving scatterers. This enables laser speckle measurements to be interpreted more quantitatively. We do this by using computer simulation of speckle data, and by experimental measurements on Brownian motion and skin perfusion using a laser Doppler system and a multiple-exposure laser speckle system. The power spectral density measurements of the light fluctuations derived using both techniques are exactly equivalent. Dermal perfusion can therefore be measured by laser Doppler or laser speckle contrast methods. In particular, multiexposure laser speckle can be rapidly processed to generate a full-field map of ...

International Nuclear Information System (INIS)

Nitrogen oxides play a critical role in the chemistry of the atmosphere and indirectly influence global warming through the production of ozone. At Barrow, Alaska, the NOAA long-term surface ozone record indicates an increase of about 2% per year during the summer months. Since NO_x (NO+NO_2) concentrations above about 30 ppt (parts per trillion) result in net ozone production in the presence of sunlight, the authors propose that the observed Barrow surface ozone increase is related to anthropogenic nitrogen oxide emissions. A high-sensitivity chemiluminescent instrument for measurements of nitrogen oxides has been built to test this hypothesis. Measurement campaigns have been conducted during summer 1988 and spring 1989, and are continuing during spring and summer 1990. Periods during which the NOV concentrations measured at the GMCC site were unaffected by local (Barrow) emissions ...

International Nuclear Information System (INIS)

Current work presents the results of more than 100 measurements of 222Rn activity in drinking water collected at artesian bores at Curitiba region during the period of 2008 - 2009. The measurements were performed at the Laboratory of Applied Nuclear Physics of the Federal University of Technology in cooperation with the Nuclear Technology Development Center (CDTN) of Brazilian Nuclear Energy Committee (CNEN). Experimental setup was based on the Professional Radon Monitor (ALPHA GUARD) connected to specific kit of glass vessels Aqua KIT through the air pump. The equipment was adjusted with air flow of 0.5 L/min. The 222Rn concentration levels were detected and analyzed by the computer every 10 minutes using the software DataEXPERT by GENITRON Instruments. Collected average levels of 222Rn concentration were processed taking into account the volume of water sample and its temperature, atmospheric pressure ...

Science.gov (United States)

Elution profiles of total lipoproteins, apolipoprotein B (apoB) concentrations in lipoproteins, and plasma triglyceride (TG) levels were examined in early-, late-, and non-lactating cows. Additionally, arteriovenous (A-V) differences were also measured to elucidate the uptake of TG and apoB-containing lipoproteins in mammary gland. Non-lactating cows showed three major peaks corresponding to triglyceride-rich lipoprotein (TRL), low density lipoprotein (LDL), and high density lipoprotein (HDL) fraction, whereas both early- and late-lactating cows revealed two peaks corresponding to TRL and HDL. The peak area of TRL in early- and late-lactating cows were significantly (p < 0.05) smaller than that in non-lactating cows. The plasma TG levels and apoB-48 concentrations of TRL in early- and late-lactating cows were also significantly (p < 0.01) lower. Furthermore, early lactating cows showed significantly (p < 0.05) ...

International Nuclear Information System (INIS)

The excess molar volumes V_m"E for binary liquid mixtures containing dipropylene glycol monomethyl ether or dipropylene glycol monobutyl ether and methanol, 1-propanol, 1-pentanol and 1-heptanol have been measured as a function of composition using a continuous dilution dilatometer at T=(288.15, 298.15, and 308.15) K and atmospheric pressure over the whole concentration range. The excess volume results allowed the following mixing quantities to be reported in all range of concentrations or at equimolar concentrations: #alpha#, volume expansivity; (#partial deriv#V_m"E/#partial deriv#T)_p; (#partial deriv#H"E/#partial deriv#P)_T at T=298.15 K. The obtained results have been compared at T=298.15 K with the calculated values by using the Flory theory of liquid mixtures. The theory predicts the #alpha#, and #alpha#"E values rather well, while the calculated values of (#partial deriv#V_m"E/#partial ...

Energy Technology Data Exchange (ETDEWEB)

In relation to coal liquefaction reaction, the effect of the coexistence of transferable hydrogen (TH) from process solvent on reduction of radical concentration and the effect of pre-heat treatment on average structure of coals were studied. In experiment, change in radical concentration with temperature rise was measured using the system composed of Yallourn coal and process solvent. The results are as follows. Process solvent with a wide boiling point range of 180-420{degree}C is effective in suppressing an increase in radical concentration even at higher temperature. The effect of hydrogen-donating solvent increases with TH. It was also suggested that high-boiling point constituents in solvent stabilize radicals even over 400{degree}C by vapor phase hydrogenation. The experimental results of pre-heat treatment are as follows. Although the conversion improvement effect of TH is equivalent to that of ...

International Nuclear Information System (INIS)

In a closed circuit formed by bypassing pipelines connected to carbon steel parts, low oxygen coolants pass there through during operation. A solution containing ions of metals more noble than iron are circulated to bring the solution into contact with the carbon steel surface of the inner wall of the parts to form a deposition membrane of the metal more noble than iron on the surface to prevent acceleration of corrosion of the carbon steel parts due to low oxygen coolants. The solution containing ions of metals more noble than iron is a solution of palladium nitrate containing ions of platinum elements. This operation is conducted under a temperature condition of from 50degC to 150degC. In addition, the metal ion concentration of the solution circulating in the closed circuit is measured, it is compared with metal ion concentration previously determined, and the results are feed back to a means for controlling water ...

International Nuclear Information System (INIS)

A new miniature high-frequency (HF) plasma source intended for bio-medical applications is studied using nitrogen/oxygen mixture at atmospheric pressure. This plasma source can be used as an element of a plasma source array for applications in dermatology and surgery. Nitric oxide and ozone which are produced in this plasma source are well-known agents for proliferation of the cells, inhalation therapy for newborn infants, disinfection of wounds and blood ozonation. Using optical emission spectroscopy, microphotography and numerical simulation, the gas temperature in the active plasma region and plasma parameters (electron density and electron distribution function) are determined for varied nitrogen/oxygen flows. The influence of the gas flows on the plasma conditions is studied. Ozone and nitric oxide concentrations in the effluent of the plasma source are measured using absorption spectroscopy and electro-chemical NO-detector at variable gas ...

Energy Technology Data Exchange (ETDEWEB)

All organisms, from bacteria and yeast to humans, respond to physical and chemical stressors by increasing the synthesis of a small group of cellular stress proteins.'' The authors have developed a simple in vitro system for quickly screening environmentally relevant stressors to detect stress-induced proteins that are good candidates for biomarkers. Polyacrylamide gel electrophoresis was used to detect stressor-induced, concentration-dependent changes in cellular stress protein levels in two fish cell culture systems, whereas simultaneous in vitro neutral red uptake cytotoxicity assays measured the stressors effect on cellular physiology. There was a direct concentration-dependent relationship between sublethal cytotoxic effects and the increases in stress protein levels. Increases of 50 to 200% were detected in stress proteins from desert topminnow, Poeciliopsis lucida, hepatoma-derived cell cultures ...

International Nuclear Information System (INIS)

The effect of concentration on the corrosion behavior of Mg-based alloy AZ91D was investigated in ethylene glycol-water solutions using electrochemical techniques i.e. potentiodynamic polarization, electrochemical impedance measurements (EIS) and surface examination via scanning electron microscope (SEM) technique. This can provide a basis for developing new coolants for magnesium alloy engine blocks. Corrosion behavior of AZ91D alloy by coolant is important in the automotive industry. It was found that the corrosion rate of AZ91D alloy decreased with increasing concentration of ethylene glycol. For AZ91D alloy in chloride >0.05 M or fluoride 0.05 M for fluoride containing ethylene glycol solution, some inhibition effect has been observed. The corrosion of AZ91D alloy in the blank can be effectively inhibited by addition of 0.05 mM paracetamol that reacts with AZ91D alloy and forms a protective film on the surface at ...

International Nuclear Information System (INIS)

In this work, the silicon oxynitride layer was studied as a tunneling layer for non-volatile memory application by fabricating low temperature polysilicon thin film transistors on glass. Silicon wafers were oxynitrided by only nitrous oxide plasma under different radio frequency powers and plasma treatment times. Plasma oxynitridation was performed in RF plasma using inductively coupled plasma chemical vapor deposition. The X-ray energy dispersive spectroscopy was employed to analyze the atomic concentration ratio of nitrogen/oxygen in oxynitride layer. The oxynitrided layer formed under radio frequency power of 150 W and substrate temperature of 623 K was found to contain the atomic concentration ratio of nitrogen/oxygen as high as 1.57. The advantage of high nitrogen concentration in silicon oxide layer formed by using nitrous oxide plasma was investigated by capacitance-voltage measurement. The ...

Energy Technology Data Exchange (ETDEWEB)

Radon exposure assessment in case-control studies on radon and lung cancer is generally based on contemporary radon concentration measurements, which can be affected by significant changes in the building structures or in living habits. Another method to estimate the radon exposure of the subjects is the recently developed retrospective dosimetry technique based on the {sup 210}Po surface activity from glass objects. In order to compare the results obtained by the two methods, a study has been carried out in a sample of 26 dwellings in Rome, with radon concentration values ranging from 28 to 623 Bq m{sup -3}. Retrospective detectors based on CR-39 and LR 115 were exposed on 50 glass objects in bedrooms and living rooms. The correlation factor between the two sets of data, after removing six extreme values, is 0.67, which is similar to results obtained in other validation studies of similar sample size. The correlation ...

International Nuclear Information System (INIS)

In the present work, a rapid deposition anodic stripping voltammetry (ASV) for determination of uranium is presented. For this purpose, the uranyl hexacyanoferrate (K2UO2[Fe(CN)6]) is deposited electrochemically on a thin palladium-aluminum electrode (Pd-Al) from a UO22+ solution in the presence of K3Fe(CN)6. Then, the well stable (K2UO2[Fe(CN)6]) on the electrode was stripped by anodic differential pulse voltammetry for measuring the UO22+ ion concentration. The effect of operational parameters, including: concentration of K3Fe(CN)6, solution pH, deposition potential, and deposition time were studied. In optimum conditions, the calibration graph was linear in the concentration range 105-7 x 10-4 mol L-1 with a detection limit of 6.2 x 10-6 mol L-1. The influence of some concomitant ions in K2UO2[Fe(CN)6] formation was investigated. The proposed method was used for the rapid determination of uranium in ...

Energy Technology Data Exchange (ETDEWEB)

A series of upper tropospheric radon concentration measurements made over the eastern Pacific and west coast of the United States during the summers of 1983 and 1984 has revealed the occurrence of unexpectedly high (>16 pCi/SCM) radon concentrations for 9 of the 61 measurements (and 6 of the 13 flights). A frequency distribution plot of the set of 61 observations shows a distinct bimodal distribution, with approximately 2/5 of the observations falling close to 1 pCi/SCM, and 3/5 falling in a high concentration mode centered at about 11 pCi/SCM. Trajectory and synoptic analyses for two of the flights on which such high radon concentrations were observed indicate that this radon-rich air originated in the Asian boundary layer, ascended in cumulus updrafts, and was carried eastward in the fast moving air on the anti-cyclonic side of the upper tropospheric jet. ...

Energy Technology Data Exchange (ETDEWEB)

The single-electrode capacitance of a nano-porous carbon electrode used as an electric double layer capacitor was measured. The charged state of the electrolyte ion was discussed from the results. Single-electrode capacitance was not proportional to the specific surface area of the electrode. This implies that the whole surface of the electrode is not effective for the formation of an electric double layer. It is considered that edge orientation of the carbon structure would give a dominant contribution to capacitance. For measurements with aqueous solutions of various electrolytes, capacitance was about the same value for each salt compound. For aqueous acid solution, on the other hand, capacitance was twice to three times as large as that for salt compounds. This difference, however, became negligibly small if the concentration of electrolyte solution was lowered. Taking account of the hydrated ionic radius of each ion, ...

Energy Technology Data Exchange (ETDEWEB)

The objective of this study is to develop an artificial neural network (ANN) model to predict the thermal conductivity of ethylene glycol-water solutions based on experimentally measured variables. The thermal conductivity of solutions at different concentrations and various temperatures was measured using the cylindrical cell method that physical properties of the solution are being determined fills the annular space between two concentric cylinders. During the experiment, heat flows in the radial direction outwards through the test liquid filled in the annual gap to cooling water. In the steady state, conduction inside the cell was described by the Fourier equation in cylindrical coordinates, with boundary conditions corresponding to heat transfer between the solution and cooling water. The performance of ANN was evaluated by a regression analysis between the predicted and the experimental values. The ...

International Nuclear Information System (INIS)

The main aims of the study were: 1) the evaluation of iron and zinc status in women of Lodz aged 18-45 years, 2) adaptation of the whole body counter to in vivo measurements absorption of iron given to the gastro-intestinal tract of volunteers and 3) in rat model estimation iron bioavailability from fortified wheat flour combined with products usually consumed in Poland. During five months investigations thirty seven women were examined each one twice in two months interval. Following variables were measured: iron and zinc in blood serum, in public and scalp hair and in food, taste acuity score, serum ferritin, hemoglobin, total iron binding capacity, red blood cells, mean corpuscular concentration and corpuscular volume. Prevalence of iron deficiency and iron deficient anemia were assessed by two models in terms of the depression of serum ferritin and hemoglobin concentrations. 64 refs, 6 figs, 23 ...

International Nuclear Information System (INIS)

Laboratory dose-response experiments with organophosphate and pyrethroid pesticides, and dose-response experiments with increasing particle loads were used to determine which of these stressors were likely responsible for the toxicity and macroinvertebrate impacts previously observed in the Salinas River. Experiments were conducted with the amphipod Hyalella azteca, the baetid mayfly Procloeon sp., and the midge Chironomus dilutus (Shobanov, formerly Chironomus tentans). The results indicate the primary stressor impacting H. azteca was pesticides, including chlorpyrifos and permethrin. The mayfly Procloeon sp. was sensitive to chlorpyrifos and permethrin within the range of concentrations of these pesticides measured in the river. Chironomus dilutus were sensitive to chlorpyrifos within the ranges of concentrations measured in the river. None of the species tested were affected by turbidity as high as ...

Science.gov (United States)

The influence of the sulfur dioxide emissions from a large copper smelter in Tacoma, Washington, USA, was studied by measuring the chemical composition of rainwater collected upwind and downwind of the source, before and after permanent closure of the smelter in 1985. Data analysis was based on a statistical model that accounted for variability associated with location of 25 sampling sites within three geographic regions, smelter operation, ten individual rain events observed over 2 years, and measurement uncertainty. After smelter closure, the upwind-downwind differences in mean hydrogen ion and excess sulfate ion concentrations within a 600 km/sup 2/ region extending to 25 km downwind of the source had decreased significantly compared to the pre-closure value. No significant decreases in mean ion concentrations were observed farther downwind in the Seattle, urban area. During five events sampled prior ...

International Nuclear Information System (INIS)

Ion bombardment during deposition can significantly modify the film properties. In the partially ionized beam deposition, ions derived from the depositing material, i.e., the self-ions, are used during deposition. Cu films were deposited on SiO_2 substrates at room temperature using 1% Cu self-ions with an energy ranging between 0--4 keV. We studied the microstructures of the Cu films using x-ray diffraction and transmission electron microscopy, measured the impurity level inside the films using secondary ion mass spectrometry, and performed the resistivity measurements using a four point probe. The results indicate that there is an optimum ion energy around 2 keV at which, the integrated x-ray intensity ratio I(111)/I(200) reaches its maximum value indicating a strong left-angle 111 right-angle texture, while the impurity concentration and resisitivity are minimum. The correlation between the structural, compositional and ...