WorldWideScience

Sample records for calculating relative air

  1. PSYCRODATA: a software which calculates the air humidity characteristics and relate its with the variations of the gamma environmental bottom

    International Nuclear Information System (INIS)

    Alonso A, D.; Dominguez L, O.; Ramos V, O.; Caveda R, C.A.; Capote F, E.; Dominguez G, A.; Valdes S, E.; Rodriguez V, E.

    2006-01-01

    The computer tool 'Psycrodata', able to calculate the values of those characteristics of the humidity of the air starting from the measurements carried out of humidity and temperature in the post of occident of the National Net of Environmental Radiological Surveillance was obtained. Among the facilities that 'Psycrodata' toasts it is the keeping the obtained information in a database facilitating the making of reports. For another part the possibility of selection of different approaches for the calculation and the introduction of the psicrometric coefficient to use, its make that each station can have the suitable psicrometric chart keeping in mind the instrumentation and the characteristics of the area of location of the same one. Also, can have facilities to import text files for later on to be plotted, it allowed to correlate the absorbed dose rate in air due to the environmental gamma radiation, besides of the temperature and the humidity, with the tension of the water steam, the temperature of the dew point and the saturation deficit. (Author)

  2. Relative Hazard Calculation Methodology

    International Nuclear Information System (INIS)

    DL Strenge; MK White; RD Stenner; WB Andrews

    1999-01-01

    The methodology presented in this document was developed to provide a means of calculating the RH ratios to use in developing useful graphic illustrations. The RH equation, as presented in this methodology, is primarily a collection of key factors relevant to understanding the hazards and risks associated with projected risk management activities. The RH equation has the potential for much broader application than generating risk profiles. For example, it can be used to compare one risk management activity with another, instead of just comparing it to a fixed baseline as was done for the risk profiles. If the appropriate source term data are available, it could be used in its non-ratio form to estimate absolute values of the associated hazards. These estimated values of hazard could then be examined to help understand which risk management activities are addressing the higher hazard conditions at a site. Graphics could be generated from these absolute hazard values to compare high-hazard conditions. If the RH equation is used in this manner, care must be taken to specifically define and qualify the estimated absolute hazard values (e.g., identify which factors were considered and which ones tended to drive the hazard estimation)

  3. Dispersion relations in loop calculations

    International Nuclear Information System (INIS)

    Kniehl, B.A.

    1996-01-01

    These lecture notes give a pedagogical introduction to the use of dispersion relations in loop calculations. We first derive dispersion relations which allow us to recover the real part of a physical amplitude from the knowledge of its absorptive part along the branch cut. In perturbative calculations, the latter may be constructed by means of Cutkosky's rule, which is briefly discussed. For illustration, we apply this procedure at one loop to the photon vacuum-polarization function induced by leptons as well as to the γf anti-f vertex form factor generated by the exchange of a massive vector boson between the two fermion legs. We also show how the hadronic contribution to the photon vacuum polarization may be extracted from the total cross section of hadron production in e + e - annihilation measured as a function of energy. Finally, we outline the application of dispersive techniques at the two-loop level, considering as an example the bosonic decay width of a high-mass Higgs boson. (author)

  4. Theoretical calculation of solid particles deposition from the air

    Directory of Open Access Journals (Sweden)

    Bobro Milan

    2002-03-01

    Full Text Available This paper presents the calculation of harmful substance deposition (air pollution from the point source (Slanèo, et al., 2001 using equation (1. The point source shall be understood as e.g. chimneys of factory, heat plant, incinerator, boiler plant, local heating plant, etc.The theoretical calculation of concentration (1, or deposition (8 is based on the study of transfer and dispersion of pollution in air (Slanèo, et al., 2000a. The movement of pollution in air consists of a movement of the air itself and a relative movement of pollution particles and air, while the movement of harmful substance in the smoke trail is under the influence of turbulent diffusion, convection and gravitation. Molecular diffusion is not important in this process. When calculating concentrations (1 and deposition (8 of air pollution on a particular place near the source, it is assumed that the air speed is constant, the direction of wind does not change with the height and the source of air pollution is time-constant. The change in the wind speed with the height depends on the stability class of atmosphere (temperature gradient (Slanèo, et al., 2000a and it is calculated using equation (10.The theoretical calculation of concentration and or deposition of harmful substance from the point source (1 and (8 shall be applied if the harmful substance particles, which leave the source, have the same density (composition, shape (spherical and size.The experimental observations of dust deposition showed the significance of 0.1-20 µm particles. The application of equation (1 to calculate the concentration is conditioned, in addition to the recognition of source parameters and meteorological conditions, by the recognition of the particle sedimentation speed, which changes with the size of particle radius (2.For a practical calculation of deposition it is therefore necessary to know the differential distribution function f(r of particle radii, which can be made on the basis

  5. Agriculture-related radiation dose calculations

    International Nuclear Information System (INIS)

    Furr, J.M.; Mayberry, J.J.; Waite, D.A.

    1987-10-01

    Estimates of radiation dose to the public must be made at each stage in the identification and qualification process leading to siting a high-level nuclear waste repository. Specifically considering the ingestion pathway, this paper examines questions of reliability and adequacy of dose calculations in relation to five stages of data availability (geologic province, region, area, location, and mass balance) and three methods of calculation (population, population/food production, and food production driven). Calculations were done using the model PABLM with data for the Permian and Palo Duro Basins and the Deaf Smith County area. Extra effort expended in gathering agricultural data at succeeding environmental characterization levels does not appear justified, since dose estimates do not differ greatly; that effort would be better spent determining usage of food types that contribute most to the total dose; and that consumption rate and the air dispersion factor are critical to assessment of radiation dose via the ingestion pathway. 17 refs., 9 figs., 32 tabs

  6. Air ingression calculations for selected plant transients using MELCOR

    International Nuclear Information System (INIS)

    Kmetyk, L.N.

    1994-01-01

    Two sets of MELCOR calculations have been completed studying the effects of air ingression on the consequences of various severe accident scenarios. One set of calculations analyzed a station blackout with surge line failure prior to vessel breach, starting from nominal operating conditions; the other set of calculations analyzed a station blackout occurring during shutdown (refueling) conditions. Both sets of analyses were for the Surry plant, a three-loop Westinghouse PWR. For both accident scenarios, a basecase calculation was done, and then repeated with air ingression from containment into the core region following core degradation and vessel failure. In addition to the two sets of analyses done for this program, a similar air-ingression sensitivity study was done as part of a low-power/shutdown PRA, with results summarized here; that PRA study also analyzed a station blackout occurring during shutdown (refueling) conditions, but for the Grand Gulf plant, a BWR/6 with Mark III containment. These studies help quantify the amount of air that would have to enter the core region to have a significant impact on the severe accident scenario, and demonstrate that one effect, of air ingression is substantial enhancement of ruthenium release. These calculations also show that, while the core clad temperatures rise more quickly due to oxidation with air rather than steam, the core also degrades and relocates more quickly, so that no sustained, enhanced core heatup is predicted to occur with air ingression

  7. A new method for calculation of an air quality index

    Energy Technology Data Exchange (ETDEWEB)

    Ilvessalo, P. [Finnish Meteorological Inst., Helsinki (Finland). Air Quality Dept.

    1995-12-31

    Air quality measurement programs in Finnish towns have expanded during the last few years. As a result of this it is more and more difficult to make use of all the measured concentration data. Citizens of Finnish towns are nowadays taking more of an interest in the air quality of their surroundings. The need to describe air quality in a simplified form has increased. Air quality indices permit the presentation of air quality data in such a way that prevailing conditions are more easily understandable than when using concentration data as such. Using an air quality index always means that some of the information about concentrations of contaminants in the air will be lost. How much information is possible to extract from a single index number depends on the calculation method. A new method for the calculation of an air quality index has been developed. This index always indicates the overstepping of an air quality guideline level. The calculation of this air quality index is performed using the concentrations of all the contaminants measured. The index gives information both about the prevailing air quality and also the short-term trend. It can also warn about the expected exceeding of guidelines due to one or several contaminants. The new index is especially suitable for the real-time monitoring and notification of air quality values. The behaviour of the index was studied using material from a measurement period in the spring of 1994 in Kaepylae, Helsinki. Material from a pre-operational period in the town of Oulu was also available. (author)

  8. A new method for calculation of an air quality index

    Energy Technology Data Exchange (ETDEWEB)

    Ilvessalo, P [Finnish Meteorological Inst., Helsinki (Finland). Air Quality Dept.

    1996-12-31

    Air quality measurement programs in Finnish towns have expanded during the last few years. As a result of this it is more and more difficult to make use of all the measured concentration data. Citizens of Finnish towns are nowadays taking more of an interest in the air quality of their surroundings. The need to describe air quality in a simplified form has increased. Air quality indices permit the presentation of air quality data in such a way that prevailing conditions are more easily understandable than when using concentration data as such. Using an air quality index always means that some of the information about concentrations of contaminants in the air will be lost. How much information is possible to extract from a single index number depends on the calculation method. A new method for the calculation of an air quality index has been developed. This index always indicates the overstepping of an air quality guideline level. The calculation of this air quality index is performed using the concentrations of all the contaminants measured. The index gives information both about the prevailing air quality and also the short-term trend. It can also warn about the expected exceeding of guidelines due to one or several contaminants. The new index is especially suitable for the real-time monitoring and notification of air quality values. The behaviour of the index was studied using material from a measurement period in the spring of 1994 in Kaepylae, Helsinki. Material from a pre-operational period in the town of Oulu was also available. (author)

  9. Application of propagation calculations in air quality control

    International Nuclear Information System (INIS)

    Kuelske, S.

    1993-01-01

    This paper describes the development of a methodics of propagation calculation since the foundation of the 'Landesanstalt fuer Immissionsschutz' in 1963, and its practical use in air quality control. In this context, it deals with methods for calculating stack heights and the Gaussian propagation model adopted by the Technical Code on Clean Air, the propagation of flue gas emitted via cooling towers, the propagation of accidentally released substances, odours and automobile emissions, and with flow and propagation calculation for the proximity zone of buildings as well as for meteorological fields with space and time variations and topographically varied terrain. (orig.) [de

  10. CALCULATION OF AIR ION REGIME IN THE CASE OF ARTIFICIAL AIR IONIZATION

    Directory of Open Access Journals (Sweden)

    BILIAIEV M. M.

    2015-10-01

    Full Text Available Purpose. One of the major tasks in the field of labor protection is providing of the necessary qualitative composition of air in the working areas of office and industrial spaces. In order to maintain the necessary air ion level in the air space premises, the artificial ionization of air is used often in the premises. At present in Ukraine analytical model are used for the calculation of air ion regime in premises, influencing on the formation process of air ions concentration field. An alternative solution is the use of CFD models, developing including the air jets aerodynamics in the premise, the presence of furniture, equipment, transfer of ions under an electric field, and other physical factors, determining intensity and shape of air ions concentration field in the premise. Methodology. Influence of air flow was taken into account in the development of CFD models for calculation of air ion regime in the apartment, caused by operation of ventilation, diffusion, electric field impact, as well as the interaction of different polarity ions with each other, and their interaction with dust particles. The proposed model of calculation of air ion regime in premises based on the use of aerodynamics, electrostatics and mass transfer levels. This model allows operatively to calculate air ions concentration field with the influence of the walls, floor, ceiling and obstacles on the process of air ions dispersion, the specific location of different polarity ions emission and their interaction in the premise and work areas in conditions of artificial air ionization. Results. The calculated data were obtained and on their base could be estimated the concentration of air ion anywhere in the premise with artificial air ionization. Ions concentration field, being calculated using this CFD model, as concentration field isolines is presented. Originality. The results of the air ion regime calculation in the premise are presented, based on numerical 2D CFD model

  11. Calculation of the dynamic air flow resistivity of fibre materials

    DEFF Research Database (Denmark)

    Tarnow, Viggo

    1997-01-01

    The acoustic attenuation of acoustic fiber materials is mainly determined by the dynamic resistivity to an oscillating air flow. The dynamic resistance is calculated for a model with geometry close to the geometry of real fibre material. The model constists of parallel cylinders placed randomly.......The second procedure is an extension to oscillating air flow of the Brinkman self-consistent procedure for dc flow. The procedures are valid for volume concentrations of cylinders less than 0.1. The calculations show that for the density of fibers of interest for acoustic fibre materials the simple self...

  12. Calculation principles of humid air in a reversed Brayton cycle

    Energy Technology Data Exchange (ETDEWEB)

    Backman, J [Lappeenranta Univ. of Technology (Finland). Dept. of Energy Technology

    1998-12-31

    The article presents a calculation method for reversed Brayton cycle that uses humid air as working medium. The reversed Brayton cycle can be employed as an air dryer, a heat pump or a refrigerating machine. In this research the use of humid air as a working fluid has an environmental advantage, as well. In this method especially the expansion process in the turbine is important because of the condensation of the water vapour in the humid air. This physical phenomena can have significant effects on the level of performance of the application. The expansion process differs physically from the compression process, when the water vapour in the humid air begins to condensate. In the thermodynamic equilibrium of the flow, the water vapour pressure in humid air cannot exceed the pressure of saturated water vapour in corresponding temperature. Expansion calculation during operation around the saturation zone is based on a quasistatic expansion, in which the system after the turbine is in thermodynamical equilibrium. The state parameters are at every moment defined by the equation of state, and there is no supercooling in the vapour. Following simplifications are used in the calculations: The system is assumed to be adiabatic. This means that there is no heat transfer to the surroundings. This is a common practice, when the temperature differences are moderate as here; The power of the cooling is omitted. The cooling construction is very dependent on the machine and the distribution of the losses; The flow is assumed to be one-dimensional, steady-state and homogenous. The water vapour condensing in the turbine can cause errors, but the errors are mainly included in the efficiency calculation. (author) 11 refs.

  13. Calculation principles of humid air in a reversed Brayton cycle

    Energy Technology Data Exchange (ETDEWEB)

    Backman, J. [Lappeenranta Univ. of Technology (Finland). Dept. of Energy Technology

    1997-12-31

    The article presents a calculation method for reversed Brayton cycle that uses humid air as working medium. The reversed Brayton cycle can be employed as an air dryer, a heat pump or a refrigerating machine. In this research the use of humid air as a working fluid has an environmental advantage, as well. In this method especially the expansion process in the turbine is important because of the condensation of the water vapour in the humid air. This physical phenomena can have significant effects on the level of performance of the application. The expansion process differs physically from the compression process, when the water vapour in the humid air begins to condensate. In the thermodynamic equilibrium of the flow, the water vapour pressure in humid air cannot exceed the pressure of saturated water vapour in corresponding temperature. Expansion calculation during operation around the saturation zone is based on a quasistatic expansion, in which the system after the turbine is in thermodynamical equilibrium. The state parameters are at every moment defined by the equation of state, and there is no supercooling in the vapour. Following simplifications are used in the calculations: The system is assumed to be adiabatic. This means that there is no heat transfer to the surroundings. This is a common practice, when the temperature differences are moderate as here; The power of the cooling is omitted. The cooling construction is very dependent on the machine and the distribution of the losses; The flow is assumed to be one-dimensional, steady-state and homogenous. The water vapour condensing in the turbine can cause errors, but the errors are mainly included in the efficiency calculation. (author) 11 refs.

  14. Calculations of air cooler for new subsonic wind tunnel

    Science.gov (United States)

    Rtishcheva, A. S.

    2017-10-01

    As part of the component development of TsAGI’s new subsonic wind tunnel where the air flow velocity in the closed test section is up to 160 m/sec hydraulic and thermal characteristics of air cooler are calculated. The air cooler is one of the most important components due to its highest hydraulic resistance in the whole wind tunnel design. It is important to minimize its hydraulic resistance to ensure the energy efficiency of wind tunnel fans and the cost-cutting of tests. On the other hand the air cooler is to assure the efficient cooling of air flow in such a manner as to maintain the temperature below 40 °C for seamless operation of measuring equipment. Therefore the relevance of this project is driven by the need to develop the air cooler that would demonstrate low hydraulic resistance of air and high thermal effectiveness of heat exchanging surfaces; insofar as the cooling section must be given up per unit time with the amount of heat Q=30 MW according to preliminary evaluations. On basis of calculation research some variants of air cooler designs are proposed including elliptical tubes, round tubes, and lateral plate-like fins. These designs differ by the number of tubes and plates, geometrical characteristics and the material of finned surfaces (aluminium or cooper). Due to the choice of component configurations a high thermal effectiveness is achieved for finned surfaces. The obtained results form the basis of R&D support in designing the new subsonic wind tunnel.

  15. Safety-related control air systems

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    This Standard applies to those portions of the control air system that furnish air required to support, control, or operate systems or portions of systems that are safety related in nuclear power plants. This Standard relates only to the air supply system(s) for safety-related air operated devices and does not apply to the safety-related air operated device or to air operated actuators for such devices. The objectives of this Standard are to provide (1) minimum system design requirements for equipment, piping, instruments, controls, and wiring that constitute the air supply system; and (2) the system and component testing and maintenance requirements

  16. Calculation of atomic integrals using commutation relations

    International Nuclear Information System (INIS)

    Zamastil, J.; Vinette, F.; Simanek, M.

    2007-01-01

    In this paper, a numerically stable method of calculating atomic integrals is suggested. The commutation relations among the components of the angular momentum and the Runge-Lenz vector are used to deduce recurrence relations for the Sturmian radial functions. The radial part of the one- and two-electron integrals is evaluated by means of these recurrence relations. The product of two radial functions is written as a linear combination of the radial functions. This enables us to write the integrals over four radial functions as a linear combination of the integrals over two radial functions. The recurrence relations for the functions are used to derive the recursion relations for the coefficients of the linear combination and for the integrals over two functions

  17. Experimental and calculated calibration of ionization chambers with air circulation

    CERN Document Server

    Peetermans, A

    1972-01-01

    The reports describes the method followed in order to calibrate the different ionization chambers with air circulation, used by the 'Health Physics Group'. The calculations agree more precisely with isotopes cited previously (/sup 11/C, /sup 13/N, /sup 15/O, /sup 41 /Ar, /sup 14/O, /sup 38/Cl) as well as for /sup 85/Kr, /sup 133/Xe, /sup 14/C and tritium which are used for the experimental standardisation of different chambers.

  18. Calculation of thermodynamic equilibrium for reactions of plutonium with air

    International Nuclear Information System (INIS)

    Zou Lexi; Sun Ying; Luo Deli; Xue Weidong; Zhu Zhenghe; Wang Rong

    2000-01-01

    There are six independent component with 4 chemical elements, i.e. PuH 2.7 (s), PuN(s), Pu 2 O 3 (s), N 2 (g) and H 2 (g), therefore, the system described involves of 2 independent reactions, both ΔG degree << O. The mass balances calculated for gas and solid phases are in good agreement with those of experimental, indicating the chemical equilibrium is nearly approached. So, it is believed that the reaction ratio of plutonium hydride with air is extremely rapid. The results are meaningful to the storage of plutonium

  19. Computer calculations of air and steam blowdown suppression

    International Nuclear Information System (INIS)

    Norris, D.M. Jr.; McMaster, W.H.; Landram, C.S.; Quinones, D.F.; Gong, E.Y.; Macken, N.A.

    1980-01-01

    We describe a computer code that combines an Eulerian incompressible-fluid algorithm (SOLA) with a Lagrangian finite-element shell algorithm. The former models the fluid and the latter models the containing structure in an analysis of pressure suppression in boiling-water reactors. The code (PELE-IC) calculates loads and structural response from air blow-down and from the oscillatory condensation of steam bubbles in a water pool. The fluid, structure, and coupling algorithms are tested by recalculating problems that have known analytical solutions, including tank drainage, spherical bubble growth, coupling for circular plates, and submerged cylinder vibration. Code calculations are also compared with the results of small-scale blowdown experiments. (orig.)

  20. A simple model for calculating air pollution within street canyons

    Science.gov (United States)

    Venegas, Laura E.; Mazzeo, Nicolás A.; Dezzutti, Mariana C.

    2014-04-01

    This paper introduces the Semi-Empirical Urban Street (SEUS) model. SEUS is a simple mathematical model based on the scaling of air pollution concentration inside street canyons employing the emission rate, the width of the canyon, the dispersive velocity scale and the background concentration. Dispersive velocity scale depends on turbulent motions related to wind and traffic. The parameterisations of these turbulent motions include two dimensionless empirical parameters. Functional forms of these parameters have been obtained from full scale data measured in street canyons at four European cities. The sensitivity of SEUS model is studied analytically. Results show that relative errors in the evaluation of the two dimensionless empirical parameters have less influence on model uncertainties than uncertainties in other input variables. The model estimates NO2 concentrations using a simple photochemistry scheme. SEUS is applied to estimate NOx and NO2 hourly concentrations in an irregular and busy street canyon in the city of Buenos Aires. The statistical evaluation of results shows that there is a good agreement between estimated and observed hourly concentrations (e.g. fractional bias are -10.3% for NOx and +7.8% for NO2). The agreement between the estimated and observed values has also been analysed in terms of its dependence on wind speed and direction. The model shows a better performance for wind speeds >2 m s-1 than for lower wind speeds and for leeward situations than for others. No significant discrepancies have been found between the results of the proposed model and that of a widely used operational dispersion model (OSPM), both using the same input information.

  1. Neurotoxicity of traffic-related air pollution.

    Science.gov (United States)

    Costa, Lucio G; Cole, Toby B; Coburn, Jacki; Chang, Yu-Chi; Dao, Khoi; Roqué, Pamela J

    2017-03-01

    The central nervous system is emerging as an important target for adverse health effects of air pollution, where it may contribute to neurodevelopmental and neurodegenerative disorders. Air pollution comprises several components, including particulate matter (PM) and ultrafine particulate matter (UFPM), gases, organic compounds, and metals. An important source of ambient PM and UFPM is represented by traffic-related air pollution, primarily diesel exhaust (DE). Human epidemiological studies and controlled animal studies have shown that exposure to air pollution, and to traffic-related air pollution or DE in particular, may lead to neurotoxicity. In particular, air pollution is emerging as a possible etiological factor in neurodevelopmental (e.g. autism spectrum disorders) and neurodegenerative (e.g. Alzheimer's disease) disorders. The most prominent effects caused by air pollution in both humans and animals are oxidative stress and neuro-inflammation. Studies in mice acutely exposed to DE (250-300μg/m 3 for 6h) have shown microglia activation, increased lipid peroxidation, and neuro-inflammation in various brain regions, particularly the hippocampus and the olfactory bulb. An impairment of adult neurogenesis was also found. In most cases, the effects of DE were more pronounced in male mice, possibly because of lower antioxidant abilities due to lower expression of paraoxonase 2. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Calculation of the Chilling Requirement for Air Conditioning in the Excavation Roadway

    Directory of Open Access Journals (Sweden)

    Yueping Qin

    2015-10-01

    Full Text Available To effectively improve the climate conditions of the excavation roadway in coal mine, the calculation of the chilling requirement taking air conditioning measures is extremely necessary. The temperature field of the surrounding rock with moving boundary in the excavation roadway was numerically simulated by using finite volume method. The unstable heat transfer coefficient between the surrounding rock and air flow was obtained via the previous calculation. According to the coupling effects of the air flow inside and outside air duct, the differential calculation mathematical model of air flow temperature in the excavation roadway was established. The chilling requirement was calculated with the selfdeveloped computer program for forecasting the required cooling capacity of the excavation roadway. A good air conditioning effect had been observed after applying the calculated results to field trial, which indicated that the prediction method and calculation procedure were reliable.

  3. Long-Term Calculations with Large Air Pollution Models

    DEFF Research Database (Denmark)

    Ambelas Skjøth, C.; Bastrup-Birk, A.; Brandt, J.

    1999-01-01

    Proceedings of the NATO Advanced Research Workshop on Large Scale Computations in Air Pollution Modelling, Sofia, Bulgaria, 6-10 July 1998......Proceedings of the NATO Advanced Research Workshop on Large Scale Computations in Air Pollution Modelling, Sofia, Bulgaria, 6-10 July 1998...

  4. Numerical calculation of air velocity and temperature in ice rinks

    Energy Technology Data Exchange (ETDEWEB)

    Bellache, O.; Galanis, N. [Sherbrooke Univ., PQ (Canada); Ouzzane, M.; Sunye, R. [Natural Resources Canada, Varennes, PQ (Canada). CANMET Energy Diversification Laboratory

    2002-07-01

    A computational fluid dynamic (CFD) model was developed to predict the energy consumption at an ice rink. Ice rinks in Canada consume approximately 3500 GWh of electricity annually and generate about 300,000 tons of gases contributing to the greenhouse effect. This newly developed model also considers ice quality and comfort conditions in the arena. The typical 2D configuration includes refrigeration loads as well as heat transfer coefficients between the air and the ice. The effects of heat losses through the ice rink envelope are also determined. A comparison of prediction results from 4 different formulations confirms that there are important differences in air velocities near the walls and in the temperature gradient near the ice. The turbulent mixed convection model gives the best estimate of the refrigeration load. It was determined that a good ventilation should circulate air throughout the building to avoid stagnant areas. Air velocities must be low near the stands where the temperature should be around 20 degrees C. Air temperature near the ice should be low to preserve ice quality and to reduce the refrigeration load. The complexity of this geometry has been taken into account in a numerical simulation of the hydrodynamic and thermal fields in the ice rink. 9 refs., 2 tabs., 5 figs.

  5. Calculation of conversion coefficients Hp(3)/K air using the PENELOPE Monte Carlo code and comparison with MCNP calculation results

    International Nuclear Information System (INIS)

    Daures, J.; Gouriou, J.; Bordy, J.M.

    2010-01-01

    The authors report calculations performed using the MNCP and PENELOPE codes to determine the Hp(3)/K air conversion coefficient which allows the Hp(3) dose equivalent to be determined from the measured value of the kerma in the air. They report the definition of the phantom, a 20 cm diameter and 20 cm high cylinder which is considered as representative of a head. Calculations are performed for an energy range corresponding to interventional radiology or cardiology (20 keV-110 keV). Results obtained with both codes are compared

  6. The influence of moisture on air oxidation of UO2: Calculations and observations

    International Nuclear Information System (INIS)

    Taylor, P.; Lemire, R.J.; Wood, D.D.

    1993-01-01

    Phase relationships among solids in the UO 2 -O 2 -H 2 O system at 25, 100, and 200C and pressures to 2 MPa have been calculated from critically evaluated thermodynamic data. Stability limits of the solids are expressed in terms of oxygen and water partial pressures at each temperature. The results are then discussed in terms of known UO 2 oxidation reactions and uranium mineralogy. Particular attention is paid to UO 3 hydrates, some of which are shown to be stable phases in air at very low relative humidities (down to ∼0.1% at 25C). This is relevant to fuel storage because of the very high molar volumes of these phases, relative to UO 2 , and consequent potential for damage to defected fuel assemblies. Comparison of the calculated phase relationships with observed UO 2 oxidation behavior helps to identify those phase interconversions that are kinetically constrained

  7. PSYCRODATA: a software which calculates the air humidity characteristics and relate its with the variations of the gamma environmental bottom; PSYCRODATA: software que calcula las caracteristicas de la humedad del aire y las relaciona con las variaciones del fondo gamma ambiental

    Energy Technology Data Exchange (ETDEWEB)

    Alonso A, D.; Dominguez L, O.; Ramos V, O.; Caveda R, C.A.; Capote F, E. [CPHR, Calle 20 No. 4113 e/41 y 47, Playa, C.P. 11300, A.P. 6195, C.P. 10600 La Habana (Cuba); Dominguez G, A.; Valdes S, E. [Instituto Superior de Ciencias y Tecnicas Aplicadas (INSTEC), La Habana (Cuba); Rodriguez V, E. [Instituto de Meteorologia (INSMET), La Habana (Cuba)]. e-mail: lola@cphr.edu.cu

    2006-07-01

    The computer tool 'Psycrodata', able to calculate the values of those characteristics of the humidity of the air starting from the measurements carried out of humidity and temperature in the post of occident of the National Net of Environmental Radiological Surveillance was obtained. Among the facilities that 'Psycrodata' toasts it is the keeping the obtained information in a database facilitating the making of reports. For another part the possibility of selection of different approaches for the calculation and the introduction of the psicrometric coefficient to use, its make that each station can have the suitable psicrometric chart keeping in mind the instrumentation and the characteristics of the area of location of the same one. Also, can have facilities to import text files for later on to be plotted, it allowed to correlate the absorbed dose rate in air due to the environmental gamma radiation, besides of the temperature and the humidity, with the tension of the water steam, the temperature of the dew point and the saturation deficit. (Author)

  8. A study on calculation method for mechanical impedance of air spring

    International Nuclear Information System (INIS)

    Changgeng, Shuai; Penghui, Li; Rustighi, Emiliano

    2016-01-01

    This paper proposes an approximate analytic method of obtaining the mechanical impedance of air spring. The sound pressure distribution in cylindrical air spring is calculated based on the linear air wave theory. The influences of different boundary conditions on the acoustic pressure field distribution in cylindrical air spring are analysed. A 1-order ordinary differential matrix equation for the state vector of revolutionary shells under internal pressure is derived based on the non-moment theory of elastic thin shell. Referring to the transfer matrix method, a kind of expanded homogeneous capacity high precision integration method is introduced to solve the non-homogeneous matrix differential equation. Combined the solved stress field of shell with the calculated sound pressure field in air spring under the displacement harmonic excitation, the approximate analytical expression of the input and transfer mechanical impedance for the air spring can be achieved. The numerical simulation with the Comsol Multiphysics software verifies the correctness of theoretical analysis result. (paper)

  9. Investigating air quality and air-related complaints in the City of Tshwane, South Africa

    CSIR Research Space (South Africa)

    Wright, C

    2011-12-01

    Full Text Available To determine the impact of implemented air quality interventions beyond ambient air pollution reductions, indicators need to be identified and appropriate health data need to be routinely collected to track air-related health. Presently, the only...

  10. Safety-related control air systems - approved 1977

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    This standard applies to those portions of the control air system that furnish air required to support, control, or operate systems or portions of systems that are safety related in nuclear power plants. This standard relates only to the air supply system(s) for safety-related air operated devices and does not apply to the safety-related air operated device or to air operated actuators for such devices. The objectives of this standard are to provide (1) minimum system design requirements for equipment, piping, instruments, controls, and wiring that constitute the air supply system; and (2) the system and component testing and maintenance requirements

  11. Calculating emissions into the air. General methodological principles; Calcul des emissions dans l'air. Principes methodologiques generaux

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-05-01

    Knowing the quantities of certain substances discharged into the atmosphere is a necessary and fundamental stage in any environmental protection policy to tackle today's problems such as acid rain, the degradation of air quality, global warming and climate change, the depletion of the ozone layer, etc. This quantification, usually known as an 'emission inventory', is built on a set of specific rules which may vary from one inventory to another. This state of affairs presents the enormous disadvantage that the data available are not comparable. At the international level, an attempt at harmonization has been going on for some years between the various international bodies. This work is being pursued in parallel with the improvement of methodologies to estimate discharges from various types of source. To take account of changes in specifications and of improvements in our understanding of phenomena giving rise to atmospheric pollution, the results of inventories of emissions need to be regularly revised, even retrospectively, to maintain a consistent series. CITEPA, which acts as a National Reference Centre, has developed a system of inventories as part of the CORALIE programme with financial help from the French Ministry for Planning and the Environment. (author)

  12. Calculating emissions into the air. General methodological principles; Calcul des emissions dans l'air. Principes methodologiques generaux

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-05-01

    Knowing the quantities of certain substances discharged into the atmosphere is a necessary and fundamental stage in any environmental protection policy to tackle today's problems such as acid rain, the degradation of air quality, global warming and climate change, the depletion of the ozone layer, etc. This quantification, usually known as an 'emission inventory', is built on a set of specific rules which may vary from one inventory to another. This state of affairs presents the enormous disadvantage that the data available are not comparable. At the international level, an attempt at harmonization has been going on for some years between the various international bodies. This work is being pursued in parallel with the improvement of methodologies to estimate discharges from various types of source. To take account of changes in specifications and of improvements in our understanding of phenomena giving rise to atmospheric pollution, the results of inventories of emissions need to be regularly revised, even retrospectively, to maintain a consistent series. CITEPA, which acts as a National Reference Centre, has developed a system of inventories as part of the CORALIE programme with financial help from the French Ministry for Planning and the Environment. (author)

  13. Air and smear sample calculational tool for Fluor Hanford Radiological control

    International Nuclear Information System (INIS)

    BAUMANN, B.L.

    2003-01-01

    A spreadsheet calculation tool was developed to automate the calculations performed for determining the concentration of airborne radioactivity and smear counting as outlined in HNF--13536, Section 5.2.7, ''Analyzing Air and Smear Samples''. This document reports on the design and testing of the calculation tool. Radiological Control Technicians (RCTs) will save time and reduce hand written and calculation errors by using an electronic form for documenting and calculating work place air samples. Current expectations are RCTs will perform an air sample and collect the filter or perform a smear for surface contamination. RCTs will then survey the filter for gross alpha and beta/gamma radioactivity and with the gross counts utilize either hand calculation method or a calculator to determine activity on the filter. The electronic form will allow the RCT with a few key strokes to document the individual's name, payroll, gross counts, instrument identifiers; produce an error free record. This productivity gain is realized by the enhanced ability to perform mathematical calculations electronically (reducing errors) and at the same time, documenting the air sample

  14. COMPUTER PROGRAM FOR CALCULATION MICROCHANNEL HEAT EXCHANGERS FOR AIR CONDITIONING SYSTEMS

    Directory of Open Access Journals (Sweden)

    Olga V. Olshevska

    2016-08-01

    Full Text Available Creating a computer program to calculate microchannel air condensers to reduce design time and carrying out variant calculations. Software packages for thermophysical properties of the working substance and the coolant, the correlation equation for calculating heat transfer, aerodynamics and hydrodynamics, the thermodynamic equations for the irreversible losses and their minimization in the heat exchanger were used in the process of creating. Borland Delphi 7 is used for creating software package.

  15. Air pollution related to sea transport

    International Nuclear Information System (INIS)

    Massin, J.M.; Hertz, O.

    1993-01-01

    Sea transportation contributes only 1-2% of world CO 2 emissions. Owing to the sulphur concentration in the bunker fuels, this transportation mode represents over 4% of the world SO 2 emissions. In addition, NO x emissions are likely to exceed 7% of the world emissions. SO 2 emissions in the North Sea and the Channel account for 15% of the whole French emissions, NO x emissions for about 10% and CO 2 emissions for about 3%. There are several potential measures to reduce the emissions of ship engines - propelling engines or generator driving engines - improvement of fuel quality, by desulphurizing and prohibiting the use of noxious additives such as PCB; use of alternative fuels; engine optimizing; exhaust gas processing; use of new propelling systems. A new organisation of world marketing of fuels with low or high sulphur levels could also be set up. The Sea Protection Committee of the International Maritime Organisation (IMO) discussed this problem during its meeting in 1990. The 73/78 MARPOL convention provides the IMO with an international juridical tool, especially designed for the preclusion of pollution due to sea transportation. It can address the issue of air pollution which requires a concerted approach between seaside countries and the drawing up of international regulations relating to the protection of the sea world. Fuel quality is already controlled by international standards drawn up by ISO. These standards should be improved to reduce air pollution due to sea transportation

  16. The Calculation of Self-Disposal Date by Analyzing the Radioactive Contamination of Air Filters Disused in Radioisotope Production Facility

    International Nuclear Information System (INIS)

    Kim, Sung Ho; Lee, Bu Hyung; Kwon, Soo Il

    2016-01-01

    The aim of the study is to decrease the diffusion of air contamination which occurred in radiation work places handle radioisotope under the permissible level. Accordingly, we replaced used air filter with a new one at the appropriate time , and computed disposal dates for disposing used air filters by calculate radioactive contamination. Air filter contaminated by radioactivity is possible to be self-disposed on condition that all detected nuclides is below permissible level according to Nuclear Safety and Security Commission (NSSC) notification No. 2014-003. Radioisotope, produced by 30, 50 MeV cyclotron and carried from other institutions, is used to treat patients, diagnose diseases, and research technology in Korea Institute of Radiological and Medical Sciences (KIRAMS). With unsealed sources generate radioactive contamination in air, it is important to use fume hood or hot cell. The accurate date needs to be calculated by the equation for calculation of self disposal date. If disposal date is in 1000 days, disposal for external institution is required. With increasing the number of medical institute which was related to use the radioisotopes, the importance of radioactive safety management was increased. As disposing radioactive waste, in particular, is the procedure of inspecting for releasing radioactive waste to outside, appropriate action and continuous research are required at a radioactive safety management.

  17. Calculation methods for air supply design in industrial facilities. Literature review

    Energy Technology Data Exchange (ETDEWEB)

    Hagstroem, K; Siren, K; Zhivov, A M

    1999-09-01

    The objectives of air distribution systems for warm air heating, ventilating, and air-conditioning are to create the proper thermal environment conditions in the occupied zone (combination of temperature, humidity, and air movement), and to control vapor and air born particle concentration within the target levels set by the process requirements and/or threshold limit values based on health effects, fire and explosion prevention, or other considerations. HVAC systems designs are constrained by existing codes, standards, and guidelines, which specify some minimum requirements for the HVAC system elements, occupant`s and process environmental quality and safety. There is a variety of different methods consulting engineers use to design room air diffusion and to select and size air diffusers, such as assumption of perfect mixing, design methods employing the empirical relations determined through research, such as the air diffusion performance index (ADPI), air jet theory and computational fluid dynamics (CFD) codes. Air supplied into the room through the various types of outlets (grills, ceiling mounted air diffusers, perforated panels etc.), is distributed by turbulent air jets. In mixing type air distribution systems, these air jets are the primary factor affecting room air motion. Numerous theoretical and experimental studies that developed a solid base for turbulent air jets theory were conducted concurrently in different countries (Germany, Sweden, Russia, U.K., USA) from the 1930`s through the 1980`s. Design methods based on air jet theory allows for the prediction of extreme values of air velocities and air temperatures in the occupied zone of empty spaces. Current air jet theory techniques account for the effects of buoyancy, confinement, jets interaction. For many conditions of jet discharge, it is possible to analyze jet performance and determine: the angle of divergence of the jet boundary; the velocity patterns along heated or chilled the jet axis; the

  18. Calculation and analysis of thermodynamic relations for superconductors

    International Nuclear Information System (INIS)

    Nazarenko, A.B.

    1989-01-01

    The absorption coefficients of high-frequency and low-frequency sound have been calculated on the basis of the Ginzburg-Landau theory. This sound is a wave of periodic adiabatic bulk compressions and rarefactions of the frequency ω in an isotropic superconductor near the transition temperature. Thermodynamic relations have been obtained for abrupt changes in the physical quantities produced as a result of a transition from the normal state to the superconducting state. These relations are similar to the Ehrenfest relations. The above--mentioned thermodynamic quantities are compared with the published experimental results on YBa 2 Cu 3 O 7-δ . The experiments on the absorption of ultrasound in recently discovered superconductors mainformation on the phase transition type and thermodynamic relations for these superconductors, in particular, the T c -vs-dp curve. Similar calculations have been carried out for 2 He-transition experiments with ferromagnetic materials. The order parameter in the thermodynamic potential was assumed to be isotropic

  19. Phenomenology and numerical calculations of lean hydrogen-air premixed flame propagation in a turbulent flow

    International Nuclear Information System (INIS)

    Faix-Gantier, A.

    2001-12-01

    This thesis concerns the study of flame propagation in a turbulent flow of lean hydrogen-air mixtures. The aim is to precise the characteristics of propagation as well as combustion and turbulence models able to take into account the peculiarities of these mixtures. This research work is related to the prevention of fire hazards associated with accidental release of hydrogen within the reactor of a nuclear power plant. In a first part, the scales (the flame velocity and thickness) associated with the laminar flame propagation in hydrogen-air mixtures are studied. A specific attention is devoted to the intrinsic instability properties of such flames. Then, the turbulence scales potentially present within a reactor are estimated in order to allow for the determination of the regimes of combustion that might be present within the reactor and among which the flamelet regime appears to be conceivable. In a second part, starting with the analysis of the propagation properties of a mean reaction zone calculated with a flamelet model, we show that, with an adequate tuning of the parameter appearing in the mean reaction rate expression, it is possible to predict numerically the turbulent flame speeds available with the literature. (author)

  20. A FIRST APPROXIMATION CALCULATION OF AIR CUSHION CHASSIS WEIGHT OF TRANSPORT AIRPLANE

    Directory of Open Access Journals (Sweden)

    2016-01-01

    Full Text Available This article describes a first approximation of a weighted estimate of air cushion chassis. The algorithm for calculating the weight of air cushion chassis allows not only to estimate the mass of the chassis to a first approximation, but also to conduct a preliminary analysis of the influence of various parameters of the aircraft and the chassis on the weight of the aircraft at the stage of before designing. The algorithm can be expanded to include additional design decisions, such as the transformation of the fuselage, increasing the air cushion chassis canopy due to extensions, center of gravity, etc.

  1. New calculation method for thermodynamic properties of humid air in humid air turbine cycle – The general model and solutions for saturated humid air

    International Nuclear Information System (INIS)

    Wang, Zidong; Chen, Hanping; Weng, Shilie

    2013-01-01

    The article proposes a new calculation method for thermodynamic properties (i.e. specific enthalpy, specific entropy and specific volume) of humid air in humid air turbine cycle. The research pressure range is from 0.1 MPa to 5 MPa. The fundamental behaviors of dry air and water vapor in saturated humid air are explored in depth. The new model proposes and verifies the relationship between total gas mixture pressure and gas component pressures. This provides a good explanation of the fundamental behaviors of gas components in gas mixture from a new perspective. Another discovery is that the water vapor component pressure of saturated humid air equals P S , always smaller than its partial pressure (f·P S ) which was believed in the past researches. In the new model, “Local Gas Constant” describes the interaction between similar molecules. “Improvement Factor” is proposed for the first time by this article, and it quantitatively describes the magnitude of interaction between dissimilar molecules. They are combined to fully describe the real thermodynamic properties of humid air. The average error of Revised Dalton's Method is within 0.1% compared to experimentally-based data. - Highlights: • Our new model is suitable to calculate thermodynamic properties of humid air in HAT cycle. • Fundamental behaviors of dry air and water vapor in saturated humid air are explored in depth. • Local-Gas-Constant describes existing alone component and Improvement Factor describes interaction between different components. • The new model proposes and verifies the relationship between total gas mixture pressure and component pressures. • It solves saturated humid air thoroughly and deviates from experimental data less than 0.1%

  2. Preliminary calculations for the CAFE project (Clean Air For Europe); Calculs preparatoires pour la strategie thematique CAFE (Clean Air For Europe)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-09-15

    The European Commission decided in 2001 an analysis program to reduce the atmospheric emissions. This report presents different limit scenari for France in 2020 (the reference scenari and the MTFR scenari, Maximum Technically Feasible Reduction), optimized scenari calculated by the RAINS model (Regional Air Pollution Information and Simulation), the costs of the scenari calculated with RAINS and the cost-benefit analysis of the strategy CAFE. From the study results, the benefits are higher than the costs, even with the most ambitious scenari. At an european level the emission reduction strategies have no effect on the employment but an impact on the Gross Domestic Product (decrease between 0,04 % and 0,12 % in function of the scenari). (A.L.B.)

  3. A comparison of measured and calculated values of air kerma rates from 137Cs in soil

    Directory of Open Access Journals (Sweden)

    V. P. Ramzaev

    2015-01-01

    Full Text Available In 2010, a study was conducted to determine the air gamma dose rate from 137Cs deposited in soil. The gamma dose rate measurements and soil sampling were performed at 30 reference plots from the south-west districts of the Bryansk region (Russia that had been heavily contaminated as a result of the Chernobyl accident. The 137Cs inventory in the top 20 cm of soil ranged from 260 kBq m–2 to 2800 kBq m–2. Vertical distributions of 137Cs in soil cores (6 samples per a plot were determined after their sectioning into ten horizontal layers of 2 cm thickness. The vertical distributions of 137Cs in soil were employed to calculate air kerma rates, K, using two independent methods proposed by Saito and Jacob [Radiat. Prot. Dosimetry, 1995, Vol. 58, P. 29–45] and Golikov et al. [Contaminated Forests– Recent Developments in Risk Identification and Future Perspective. Kluwer Academic Publishers, 1999. – P. 333–341]. A very good coincidence between the methods was observed (Spearman’s rank coefficient of correlation = 0.952; P<0.01; on average, a difference between the kerma rates calculated with two methods did not exceed 3%. The calculated air kerma rates agreed with the measured dose rates in air very well (Spearman’s coefficient of correlation = 0.952; P<0.01. For large grassland plots (n=19, the measured dose rates were on average 6% less than the calculated kerma rates. The tested methods for calculating the air dose rate from 137Cs in soil can be recommended for practical studies in radiology and radioecology. 

  4. Calculating excess lifetime risk in relative risk models

    International Nuclear Information System (INIS)

    Vaeth, M.; Pierce, D.A.

    1990-01-01

    When assessing the impact of radiation exposure it is common practice to present the final conclusions in terms of excess lifetime cancer risk in a population exposed to a given dose. The present investigation is mainly a methodological study focusing on some of the major issues and uncertainties involved in calculating such excess lifetime risks and related risk projection methods. The age-constant relative risk model used in the recent analyses of the cancer mortality that was observed in the follow-up of the cohort of A-bomb survivors in Hiroshima and Nagasaki is used to describe the effect of the exposure on the cancer mortality. In this type of model the excess relative risk is constant in age-at-risk, but depends on the age-at-exposure. Calculation of excess lifetime risks usually requires rather complicated life-table computations. In this paper we propose a simple approximation to the excess lifetime risk; the validity of the approximation for low levels of exposure is justified empirically as well as theoretically. This approximation provides important guidance in understanding the influence of the various factors involved in risk projections. Among the further topics considered are the influence of a latent period, the additional problems involved in calculations of site-specific excess lifetime cancer risks, the consequences of a leveling off or a plateau in the excess relative risk, and the uncertainties involved in transferring results from one population to another. The main part of this study relates to the situation with a single, instantaneous exposure, but a brief discussion is also given of the problem with a continuous exposure at a low-dose rate

  5. ZZ AIRFEWG, Gamma, Neutron Transport Calculation in Air Using FEWG1 Cross-Section

    International Nuclear Information System (INIS)

    1985-01-01

    1 - Description of program or function: Format: ANISN; Number of groups: 37 neutron / 21 gamma-ray; Nuclides: air (79% N and 21% O); Origin: DLC-0031/FEWG1 cross sections (ENDF/B-IV). Weighting spectrum: 1/E. The AIRFEWG library has been generated by an ANISN multigroup calculation of gamma-ray, neutron, and secondary gamma-ray transport in infinite homogeneous air using DLC-0031/FEWG1 cross sections. 2 - Method of solution: The results were generated with a P3, ANISN run with a source in a single energy group. Thus, 58 such runs were required. For sources in the 37 neutron groups, both neutron and secondary gamma-ray fluence results were calculated. For gamma-ray sources only gamma-ray fluences were calculated

  6. Source terms in relation to air cleaning

    International Nuclear Information System (INIS)

    Bernero, R.M.

    1985-01-01

    There are two sets of source terms for consideration in air cleaning, those for routine releases and those for accident releases. With about 1000 reactor years of commercial operating experience in the US done, there is an excellent data base for routine and expected transient releases. Specifications for air cleaning can be based on this body of experience with confidence. Specifications for air cleaning in accident situations is another matter. Recent investigations of severe accident behavior are offering a new basis for source terms and air cleaning specifications. Reports by many experts in the field describe an accident environment notably different from previous models. It is an atmosphere heavy with aerosols, both radioactive and inert. Temperatures are sometimes very high; radioiodine is typically in the form of cesium iodide aerosol particles; other nuclides, such as tellurium, are also important aerosols. Some of the present air cleaning requirements may be very important in light of these new accident behavior models. Others may be wasteful or even counterproductive. The use of the new data on accident behavior models to reevaluate requirements promptly is discussed

  7. Evaluating methods for estimating space-time paths of individuals in calculating long-term personal exposure to air pollution

    Science.gov (United States)

    Schmitz, Oliver; Soenario, Ivan; Vaartjes, Ilonca; Strak, Maciek; Hoek, Gerard; Brunekreef, Bert; Dijst, Martin; Karssenberg, Derek

    2016-04-01

    Air pollution is one of the major concerns for human health. Associations between air pollution and health are often calculated using long-term (i.e. years to decades) information on personal exposure for each individual in a cohort. Personal exposure is the air pollution aggregated along the space-time path visited by an individual. As air pollution may vary considerably in space and time, for instance due to motorised traffic, the estimation of the spatio-temporal location of a persons' space-time path is important to identify the personal exposure. However, long term exposure is mostly calculated using the air pollution concentration at the x, y location of someone's home which does not consider that individuals are mobile (commuting, recreation, relocation). This assumption is often made as it is a major challenge to estimate space-time paths for all individuals in large cohorts, mostly because limited information on mobility of individuals is available. We address this issue by evaluating multiple approaches for the calculation of space-time paths, thereby estimating the personal exposure along these space-time paths with hyper resolution air pollution maps at national scale. This allows us to evaluate the effect of the space-time path and resulting personal exposure. Air pollution (e.g. NO2, PM10) was mapped for the entire Netherlands at a resolution of 5×5 m2 using the land use regression models developed in the European Study of Cohorts for Air Pollution Effects (ESCAPE, http://escapeproject.eu/) and the open source software PCRaster (http://www.pcraster.eu). The models use predictor variables like population density, land use, and traffic related data sets, and are able to model spatial variation and within-city variability of annual average concentration values. We approximated space-time paths for all individuals in a cohort using various aggregations, including those representing space-time paths as the outline of a persons' home or associated parcel

  8. A new method to calculate permeability of gob for air leakage calculations and for improvements in methane control

    Energy Technology Data Exchange (ETDEWEB)

    Karacan, C.O. [National Inst. for Occupational Safety and Health, Pittsburgh, PA (United States). Office of Mine Safety and Health Research

    2010-07-01

    Although longwall underground mining can maximize coal production, it causes large scale disturbances of the surrounding rock mass due to fracturing and caving of the mine roof as the mine face advances. The porosity and permeability of the longwall gob can affect the methane and air flow patterns considerably. Since methane is a major hazard in underground coal mining operations, extensive methane control techniques are used to supplement the existing mine ventilation system, such as gob gas ventholes (GGV). However, the gob is rarely accessible for performing direct measurements of porosity and permeability. Therefore, this study presented a fractal approach for calculating the porosity and permeability from the size distribution of broken rock material in the gob, which can be determined from image analyses. The fractal approach constructs flow equations and fractal crushing equations for granular materials to predict porosity for a completely fragmented porous medium. The virtual fragmented fractal porous medium is exposed to various uniaxial stresses to simulate gob compaction and porosity and permeability changes during this process. It was concluded that the use of this fractal approach will result in better predictions regarding the flow amount and flow patterns in the gob, and facilitate leakage calculations and methane control projections. 29 refs., 4 tabs., 5 figs.

  9. Relative efficiency calculation of a HPGe detector using MCNPX code

    International Nuclear Information System (INIS)

    Medeiros, Marcos P.C.; Rebello, Wilson F.; Lopes, Jose M.; Silva, Ademir X.

    2015-01-01

    High-purity germanium detectors (HPGe) are mandatory tools for spectrometry because of their excellent energy resolution. The efficiency of such detectors, quoted in the list of specifications by the manufacturer, frequently refers to the relative full-energy peak efficiency, related to the absolute full-energy peak efficiency of a 7.6 cm x 7.6 cm (diameter x height) NaI(Tl) crystal, based on the 1.33 MeV peak of a 60 Co source positioned 25 cm from the detector. In this study, we used MCNPX code to simulate a HPGe detector (Canberra GC3020), from Real-Time Neutrongraphy Laboratory of UFRJ, to survey the spectrum of a 60 Co source located 25 cm from the detector in order to calculate and confirm the efficiency declared by the manufacturer. Agreement between experimental and simulated data was achieved. The model under development will be used for calculating and comparison purposes with the detector calibration curve from software Genie2000™, also serving as a reference for future studies. (author)

  10. Air quality along motorways. Measuring and modelling calculations; Luftkvalitet langs motorveje. Maelekampagne og modelberegninger

    Energy Technology Data Exchange (ETDEWEB)

    Solvang Jensen, S.; Loefstroem, P.; Berkowich, R.; Roerdam Olsen, H.; Frydendall, J. [DMU, Afd. for Atmosfaerisk Miljoe, Roskilde (DK); Fuglsang, K. [FORCE Technology, Broendby (Denmark); Hummelshoej, P. [MetSupport, Roskilde (Denmark)

    2004-12-01

    This report describes the air quality along Koege Bugt motorway, one of the most trafficked sections in Denmark. A number of measurements have been carried out along Koege Bugt motorway at Greve for a three-month period in the autumn of 2003. For the first time in Denmark, NO{sub x} were measured with high time dissolution from different distances of the motorway. Furthermore, a number of meteorological parameters were measured in order to map local meteorological conditions. An air quality model describing dispersal and conversion has been made on the basis of the OML model. The OML model is modified in order to take traffic-made turbulence into consideration. The model has been evaluated through comparisons between measurements and simulated calculations. Furthermore, simulated calculations for the year 2003 has been made for comparison with extreme values. (BA)

  11. The Development and Calculation of an Energy-saving Plant for Obtaining Water from Atmospheric Air

    Science.gov (United States)

    Uglanov, D. A.; Zheleznyak, K. E.; Chertykovsev, P. A.

    2018-01-01

    The article shows the calculation of characteristics of energy-efficient water generator from atmospheric air. This installation or the atmospheric water generator is the unique mechanism which produces safe drinking water by extraction it from air. The existing atmospheric generators allow to receive safe drinking water by means of process of condensation at air humidity at least equal to 35% and are capable to give to 25 liters of water in per day, and work from electricity. Authors offer to use instead of the condenser in the scheme of installation for increase volume of produced water by generator in per day, the following refrigerating machines: the vapor compression refrigerating machines (VCRM), the thermoelectric refrigerating machines (TRM) and the Stirling-cycle refrigerating machines (SRM). The paper describes calculation methods for each of refrigerating systems. Calculation of technical-and-economic indexes for the atmospheric water generator was carried out and the optimum system with the maximum volume of received water in per day was picked up. The atmospheric water generator which is considered in article will work from autonomous solar power station.

  12. A relation between calculated human body exergy consumption rate and subjectively assessed thermal sensation

    DEFF Research Database (Denmark)

    Simone, Angela; Kolarik, Jakub; Iwamatsu, Toshiya

    2011-01-01

    occupants, it is reasonable to consider both the exergy flows in building and those within the human body. Until now, no data have been available on the relation between human-body exergy consumption rates and subjectively assessed thermal sensation. The objective of the present work was to relate thermal...... sensation data, from earlier thermal comfort studies, to calculated human-body exergy consumption rates. The results show that the minimum human body exergy consumption rate is associated with thermal sensation votes close to thermal neutrality, tending to the slightly cool side of thermal sensation....... Generally, the relationship between air temperature and the exergy consumption rate, as a first approximation, shows an increasing trend. Taking account of both convective and radiative heat exchange between the human body and the surrounding environment by using the calculated operative temperature, exergy...

  13. Relative Hazard and Risk Measure Calculation Methodology Rev 1

    International Nuclear Information System (INIS)

    Stenner, Robert D.; White, Michael K.; Strenge, Dennis L.; Aaberg, Rosanne L.; Andrews, William B.

    2000-01-01

    Documentation of the methodology used to calculate relative hazard and risk measure results for the DOE complex wide risk profiles. This methodology is used on major site risk profiles. In February 1997, the Center for Risk Excellence (CRE) was created and charged as a technical, field-based partner to the Office of Science and Risk Policy (EM-52). One of the initial charges to the CRE is to assist the sites in the development of ''site risk profiles.'' These profiles are to be relatively short summaries (periodically updated) that present a broad perspective on the major risk related challenges that face the respective site. The risk profiles are intended to serve as a high-level communication tool for interested internal and external parties to enhance the understanding of these risk-related challenges. The risk profiles for each site have been designed to qualitatively present the following information: (1) a brief overview of the site, (2) a brief discussion on the historical mission of the site, (3) a quote from the site manager indicating the site's commitment to risk management, (4) a listing of the site's top risk-related challenges, (5) a brief discussion and detailed table presenting the site's current risk picture, (6) a brief discussion and detailed table presenting the site's future risk reduction picture, and (7) graphic illustrations of the projected management of the relative hazards at the site. The graphic illustrations were included to provide the reader of the risk profiles with a high-level mental picture to associate with all the qualitative information presented in the risk profile. Inclusion of these graphic illustrations presented the CRE with the challenge of how to fold this high-level qualitative risk information into a system to produce a numeric result that would depict the relative change in hazard, associated with each major risk management action, so it could be presented graphically. This report presents the methodology developed

  14. Perception of cabin air quality in airline crew related to air humidification, on intercontinental flights.

    Science.gov (United States)

    Lindgren, T; Norbäck, D; Wieslander, G

    2007-06-01

    The influence of air humidification in aircraft, on perception of cabin air quality among airline crew (N = 71) was investigated. In-flight investigations were performed in the forward part and in the aft part on eight intercontinental flights with one Boeing 767 individually, equipped with an evaporation humidifier combined with a dehumidifying unit, to reduce accumulation of condensed water in the wall construction. Four flights had the air humidification active when going out, and turned off on the return flight. The four others had the inverse humidification sequence. The sequences were randomized, and double blind. Air humidification increased relative air humidity (RH) by 10% in forward part, and by 3% in aft part of the cabin and in the cockpit. When the humidification device was active, the cabin air was perceived as being less dry (P = 0.008), and fresher (P = 0.002). The mean concentration of viable bacteria (77-108 cfu/m(3)), viable molds (74-84 cfu/m(3)), and respirable particles (1-8 microg/m3) was low, both during humidified and non-humidified flights. On flights with air humidification, there were less particles in the forward part of the aircraft (P = 0.01). In conclusion, RH can be slightly increased by using ceramic evaporation humidifier, without any measurable increase of microorganisms in cabin air. The cabin air quality was perceived as being better with air humidification. PRACTICAL IMPLICATION: Relative air humidity is low (10-20%) during intercontinental flights, and can be increased by using ceramic evaporation humidifier, without any measurable increase of microorganism in cabin air. Air humidification could increase the sensation of better cabin air quality.

  15. GUIDE TO CALCULATING TRANSPORT EFFICIENCY OF AEROSOLS IN OCCUPATIONAL AIR SAMPLING SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Hogue, M.; Hadlock, D.; Thompson, M.; Farfan, E.

    2013-11-12

    This report will present hand calculations for transport efficiency based on aspiration efficiency and particle deposition losses. Because the hand calculations become long and tedious, especially for lognormal distributions of aerosols, an R script (R 2011) will be provided for each element examined. Calculations are provided for the most common elements in a remote air sampling system, including a thin-walled probe in ambient air, straight tubing, bends and a sample housing. One popular alternative approach would be to put such calculations in a spreadsheet, a thorough version of which is shared by Paul Baron via the Aerocalc spreadsheet (Baron 2012). To provide greater transparency and to avoid common spreadsheet vulnerabilities to errors (Burns 2012), this report uses R. The particle size is based on the concept of activity median aerodynamic diameter (AMAD). The AMAD is a particle size in an aerosol where fifty percent of the activity in the aerosol is associated with particles of aerodynamic diameter greater than the AMAD. This concept allows for the simplification of transport efficiency calculations where all particles are treated as spheres with the density of water (1g cm-3). In reality, particle densities depend on the actual material involved. Particle geometries can be very complicated. Dynamic shape factors are provided by Hinds (Hinds 1999). Some example factors are: 1.00 for a sphere, 1.08 for a cube, 1.68 for a long cylinder (10 times as long as it is wide), 1.05 to 1.11 for bituminous coal, 1.57 for sand and 1.88 for talc. Revision 1 is made to correct an error in the original version of this report. The particle distributions are based on activity weighting of particles rather than based on the number of particles of each size. Therefore, the mass correction made in the original version is removed from the text and the calculations. Results affected by the change are updated.

  16. Calculation of age-dependent dose conversion coefficients for radionuclides uniformly distributed in air

    International Nuclear Information System (INIS)

    Hung, Tran Van; Satoh, Daiki; Takahashi, Fumiaki; Tsuda, Shuichi; Endo, Akira; Saito, Kimiaki; Yamaguchi, Yasuhiro

    2005-02-01

    Age-dependent dose conversion coefficients for external exposure to photons emitted by radionuclides uniformly distributed in air were calculated. The size of the source region in the calculation was assumed to be effectively semi-infinite in extent. Firstly, organ doses were calculated with a series of age-specific MIRD-5 type phantoms using MCNP code, a Monte Carlo transport code. The calculations were performed for mono-energetic photon sources of twelve energies from 10 keV to 5 MeV and for phantoms of newborn, 1, 5, 10 and 15 years, and adult. Then, the effective doses to the different age-phantoms from the mono-energetic photon sources were estimated based on the obtained organ doses. The calculated effective doses were used to interpolate the conversion coefficients of the effective doses for 160 radionuclides, which are important for dose assessment of nuclear facilities. In the calculation, energies and intensities of emitted photons from radionuclides were taken from DECDC, a recent compilation of decay data for radiation dosimetry developed at JAERI. The results are tabulated in the form of effective dose per unit concentration and time (Sv per Bq s m -3 ). (author)

  17. Indoor and Outdoor Air Pollution- related Health Problem in Ethiopia ...

    African Journals Online (AJOL)

    Background: The health effects of air pollution are generally global problems, but they have, since recently become issues of particular concern for developing countries. This review assessed the situation of air pollution and related health effects in the context of Ethiopia. Methods: The materials reviewed in this publication ...

  18. Assessment of the biomass related indoor air pollution in Kwale ...

    African Journals Online (AJOL)

    Background: Indoor air pollution remains an important health problem in some countries. Although research data on this issue is available, routine monitoring in affected areas is limited. The aims of this study were to quantify exposure to biomass- related indoor air pollution; assess the respiratory health of subjects; and ...

  19. Analytic calculation of radio emission from parametrized extensive air showers: A tool to extract shower parameters

    Science.gov (United States)

    Scholten, O.; Trinh, T. N. G.; de Vries, K. D.; Hare, B. M.

    2018-01-01

    The radio intensity and polarization footprint of a cosmic-ray induced extensive air shower is determined by the time-dependent structure of the current distribution residing in the plasma cloud at the shower front. In turn, the time dependence of the integrated charge-current distribution in the plasma cloud, the longitudinal shower structure, is determined by interesting physics which one would like to extract, such as the location and multiplicity of the primary cosmic-ray collision or the values of electric fields in the atmosphere during thunderstorms. To extract the structure of a shower from its footprint requires solving a complicated inverse problem. For this purpose we have developed a code that semianalytically calculates the radio footprint of an extensive air shower given an arbitrary longitudinal structure. This code can be used in an optimization procedure to extract the optimal longitudinal shower structure given a radio footprint. On the basis of air-shower universality we propose a simple parametrization of the structure of the plasma cloud. This parametrization is based on the results of Monte Carlo shower simulations. Deriving the parametrization also teaches which aspects of the plasma cloud are important for understanding the features seen in the radio-emission footprint. The calculated radio footprints are compared with microscopic CoREAS simulations.

  20. DIDEM - An integrated model for comparative health damage costs calculation of air pollution

    Science.gov (United States)

    Ravina, Marco; Panepinto, Deborah; Zanetti, Maria Chiara

    2018-01-01

    Air pollution represents a continuous hazard to human health. Administration, companies and population need efficient indicators of the possible effects given by a change in decision, strategy or habit. The monetary quantification of health effects of air pollution through the definition of external costs is increasingly recognized as a useful indicator to support decision and information at all levels. The development of modelling tools for the calculation of external costs can provide support to analysts in the development of consistent and comparable assessments. In this paper, the DIATI Dispersion and Externalities Model (DIDEM) is presented. The DIDEM model calculates the delta-external costs of air pollution comparing two alternative emission scenarios. This tool integrates CALPUFF's advanced dispersion modelling with the latest WHO recommendations on concentration-response functions. The model is based on the impact pathway method. It was designed to work with a fine spatial resolution and a local or national geographic scope. The modular structure allows users to input their own data sets. The DIDEM model was tested on a real case study, represented by a comparative analysis of the district heating system in Turin, Italy. Additional advantages and drawbacks of the tool are discussed in the paper. A comparison with other existing models worldwide is reported.

  1. Calculation of coolant temperature sensitivity related to thermohydraulic parameters

    International Nuclear Information System (INIS)

    Silva, F.C. da; Andrade Lima, F.R. de

    1985-01-01

    It is verified the viability to apply the generalized Perturbation Theory (GPT) in the calculation of sensitivity for thermal-hydraulic problems. It was developed the TEMPERA code in FORTRAN-IV to transient calculations in the axial temperature distribution in a channel of PWR reactor and the associated importance function, as well as effects of variations of thermalhydraulic parameters in the coolant temperature. The results are compared with one which were obtained by direct calculation. (M.C.K.) [pt

  2. Advanced Architectures and Relatives of Air Electrodes in Zn–Air Batteries

    Science.gov (United States)

    Pan, Jing; Xu, Yang Yang; Yang, Huan; Dong, Zehua; Liu, Hongfang

    2018-01-01

    Abstract Zn–air batteries are becoming the promising power sources for portable and wearable electronic devices and hybrid/electric vehicles because of their high specific energy density and the low cost for next‐generation green and sustainable energy technologies. An air electrode integrated with an oxygen electrocatalyst is the most important component and inevitably determines the performance and cost of a Zn–air battery. This article presents exciting advances and challenges related to air electrodes and their relatives. After a brief introduction of the Zn–air battery, the architectures and oxygen electrocatalysts of air electrodes and relevant electrolytes are highlighted in primary and rechargeable types with different configurations, respectively. Moreover, the individual components and major issues of flexible Zn–air batteries are also highlighted, along with the strategies to enhance the battery performance. Finally, a perspective for design, preparation, and assembly of air electrodes is proposed for the future innovations of Zn–air batteries with high performance. PMID:29721418

  3. Analysis of air temperature and relative humidity: study of microclimates

    OpenAIRE

    Elis Dener Lima Alves; Marcelo Sacardi Biudes

    2012-01-01

    Understanding the variability of climate elements in time and space is fundamental to the knowledge of the dynamics of microclimate. Thus, the objective was to analyze the variability of air temperature and relative humidity on the Cuiabá campus of the Federal University of Mato Grosso, and, through the clustering technique, to analyze the formation of groups to propose a zoning microclimate in the area study. To this end, collection data of air temperature and relative humidity at 15 points ...

  4. Calculation and analysis of the mobility and diffusion coefficient of thermal electrons in methane/air premixed flames

    KAUST Repository

    Bisetti, Fabrizio

    2012-12-01

    Simulations of ion and electron transport in flames routinely adopt plasma fluid models, which require transport coefficients to compute the mass flux of charged species. In this work, the mobility and diffusion coefficient of thermal electrons in atmospheric premixed methane/air flames are calculated and analyzed. The electron mobility is highest in the unburnt region, decreasing more than threefold across the flame due to mixture composition effects related to the presence of water vapor. Mobility is found to be largely independent of equivalence ratio and approximately equal to 0.4m 2V -1s -1 in the reaction zone and burnt region. The methodology and results presented enable accurate and computationally inexpensive calculations of transport properties of thermal electrons for use in numerical simulations of charged species transport in flames. © 2012 The Combustion Institute.

  5. Calculation of the net emission coefficient of an air thermal plasma at very high pressure

    International Nuclear Information System (INIS)

    Billoux, T; Cressault, Y; Teulet, Ph; Gleizes, A

    2012-01-01

    The aim of this paper is to present an accurate evaluation of the phenomena appearing for high pressure air plasmas supposed to be in local thermodynamic equilibrium (LTE). In the past, we already calculated the net emission coefficient for air mixtures at atmospheric pressure and for temperatures up to 30kK (molecular contribution being restricted to 10kK). Unfortunately, the existence of high pressures does not allow us to use this database due to the non-ideality of the plasma (Viriel and Debye corrections, energy cut-off ...), and due to the significant shifts of molecular reactions towards upper temperatures. Consequently, this paper proposes an improvement of our previous works with a consideration of high pressure corrections in the composition algorithm in order to take into account the pressure effects, and with a new calculation of all the contributions of the plasma radiation (atomic lines and continuum, molecular continuum, and molecular bands) using an updated database. A particular attention is paid to calculate the contribution of all the major molecular band systems to the radiation: O 2 (Schumann–Runge), N 2 (VUV, 1st and 2nd positive), NO (IR, β, γ, δ, element of ) and N 2 + (1st negative and Meinel). The discrete atomic lines and molecular bands radiation including the overlapping are calculated by a line-by-line method up to 30kK and 100 bar. This updated database is validated in the case of optically thin plasmas and pressure of 1bar by the comparison of our integrated emission strength with the published results. Finally, this work shows the necessity to extend the molecular radiation database up to 15kK at high pressure (bands and continuum) since their corresponding contributions could not be neglected at high temperature.

  6. A conversion method of air kerma from the primary, scatter, and leakage radiations to effective dose for calculating x-ray shielding barriers in mammography

    International Nuclear Information System (INIS)

    Kharrati, Hedi

    2005-01-01

    In this study, a new approach has been introduced for derivation of the effective dose from air kerma to calculate shielding requirements in mammography facilities. This new approach has been used to compute the conversion coefficients relating air kerma to the effective dose for the mammography reference beam series of the Netherlands Metrology Institute Van Swinden Laboratorium, National Institute of Standards and Technology, and International Atomic Energy Agency laboratories. The results show that, in all cases, the effective dose in mammography energy range is less than 25% of the incident air kerma for the primary and the scatter radiations and does not exceed 75% for the leakage radiation

  7. HEDO-2, Magnetic Field Calculation and Plot of Air Core Coils

    International Nuclear Information System (INIS)

    Preis, H.; Martin, P.

    1979-01-01

    1 - Nature of physical problem solved: HEDO-2 allows calculation of the magnetic field, magnetic volume forces, and the self and mutual inductance coefficients of arbitrary air-core coil systems. In addition, the program is suitable for the calculation and graphic representation of field and contour lines (lines B = const). 2 - Method of solution: Approximation of the spatially distributed currents by line currents, in which the number of closed line currents per coil can be freely chosen in accordance with the calculating accuracy required. All types of calculations possible with HEDO-2 are based on the field representation of line currents. 3 - Restrictions on the complexity of the problem: (a) The coils must have rectangular winding cross sections. (b) The contour of each coil must be symmetric to at least one coordinate axis. (c) The function describing the contour and the derivative of the function must be continuous. (d) Maximum number of coils n=200; (e) Maximum number of test points p=2000; (f) Test points ought not to be located on a line conductor

  8. Heat Transfer Coefficient at Cast-Mold Interface During Centrifugal Casting: Calculation of Air Gap

    Science.gov (United States)

    Bohacek, Jan; Kharicha, Abdellah; Ludwig, Andreas; Wu, Menghuai; Karimi-Sibaki, Ebrahim

    2018-06-01

    During centrifugal casting, the thermal resistance at the cast-mold interface represents a main blockage mechanism for heat transfer. In addition to the refractory coating, an air gap begins to form due to the shrinkage of the casting and the mold expansion, under the continuous influence of strong centrifugal forces. Here, the heat transfer coefficient at the cast-mold interface h has been determined from calculations of the air gap thickness d a based on a plane stress model taking into account thermoelastic stresses, centrifugal forces, plastic deformations, and a temperature-dependent Young's modulus. The numerical approach proposed here is rather novel and tries to offer an alternative to the empirical formulas usually used in numerical simulations for a description of a time-dependent heat transfer coefficient h. Several numerical tests were performed for different coating thicknesses d C, rotation rates Ω, and temperatures of solidus T sol. Results demonstrated that the scenario at the interface is unique for each set of parameters, hindering the possibility of employing empirical formulas without a preceding experiment being performed. Initial values of h are simply equivalent to the ratio of the coating thermal conductivity and its thickness ( 1000 Wm-2 K-1). Later, when the air gap is formed, h drops exponentially to values at least one order of magnitude smaller ( 100 Wm-2 K-1).

  9. Model calculated global, regional and megacity premature mortality due to air pollution

    Directory of Open Access Journals (Sweden)

    J. Lelieveld

    2013-07-01

    Full Text Available Air pollution by fine particulate matter (PM2.5 and ozone (O3 has increased strongly with industrialization and urbanization. We estimate the premature mortality rates and the years of human life lost (YLL caused by anthropogenic PM2.5 and O3 in 2005 for epidemiological regions defined by the World Health Organization (WHO. This is based upon high-resolution global model calculations that resolve urban and industrial regions in greater detail compared to previous work. Results indicate that 69% of the global population is exposed to an annual mean anthropogenic PM2.5 concentration of >10 μg m−3 (WHO guideline and 33% to > 25 μg m−3 (EU directive. We applied an epidemiological health impact function and find that especially in large countries with extensive suburban and rural populations, air pollution-induced mortality rates have been underestimated given that previous studies largely focused on the urban environment. We calculate a global respiratory mortality of about 773 thousand/year (YLL ≈ 5.2 million/year, 186 thousand/year by lung cancer (YLL ≈ 1.7 million/year and 2.0 million/year by cardiovascular disease (YLL ≈ 14.3 million/year. The global mean per capita mortality caused by air pollution is about 0.1% yr−1. The highest premature mortality rates are found in the Southeast Asia and Western Pacific regions (about 25% and 46% of the global rate, respectively where more than a dozen of the most highly polluted megacities are located.

  10. Calculating humid air. Can it be done without a Mollier diagram?; Rekenen aan vochtige lucht. Kan het zonder Mollierdiagram?

    Energy Technology Data Exchange (ETDEWEB)

    Veerman, J. [Royal Haskoning - Buildings, Rotterdam (Netherlands)

    2012-03-15

    An overview is given of available formulas to calculate air conditioning in the form of tables and charts. [Dutch] Dit artikel geeft een overzicht van beschikbare formules die worden gepresenteerd in overzichtelijke tabellen en diagrammen.

  11. [Traffic related air pollution and population health: a review about São Paulo (SP), Brazil].

    Science.gov (United States)

    de Toledo, Giovana Iara Ferreira Moser; Nardocci, Adelaide Cássia

    2011-09-01

    Air pollution is an important problem for São Paulo city and vehicles are the main source. About 11 million people are exposed to this pollution. To examine studies realized about air pollution and its effects on health of the population of São Paulo (Brazil) and methods of assessing exposure to pollution related to traffic. We performed a literature review using the keywords "air pollution", "São Paulo", and traffic-related air pollution. As results were obtained several studies that found relation between air pollution in São Paulo and respiratory and cardiovascular problems, fetal growth, increased mortality and hospitalizations, particularly in children and elderly people. In order to estimate the exposure, most of these studies consider the isotropic distribution of pollutants throughout the area, what prevents the evaluation of and the influence of traffic. Several methods have been used to analyze the air traffic exposure, which can be used isolated or combined. It is believed that the combination of models used to calculate pollutant concentrations to methods of georeferencing is the most appropriate approach for similar studies in São Paulo. The advantages of these methods are the ability to identify priority areas and situations, obtaining detailed information for adoption of public policies or measures, and to simulate different scenarios. The application of these methods in studies at São Paulo depends on the improvement of input data, air quality meteorological monitoring net enhancement and data of traffic volume.

  12. First-principles calculation on electronic properties of zinc oxide by zinc–air system

    Directory of Open Access Journals (Sweden)

    Ahmad Azmin Mohamad

    2017-07-01

    Full Text Available First-principles calculations are performed to study the electronic properties of zinc oxide (ZnO formed on an anode after discharging a Zn–air system. Prior to calculation, the ZnO is characterised by X-ray diffraction using Rietveld refinement. Diffracted patterns proved the formation of single phase ZnO, while Rietveld analysis shows that the ZnO has a hexagonal wurtzite structure with lattice parameters, a = 3.244 and c = 5.199 Å. Geometry optimisation of the hexagonal wurtzite structure of the ZnO is performed using various exchange–correlation energy functionals. The local density approximation functional method is used to explain the structure, electronic band structure and density of state properties of hexagonal ZnO. The calculated energy band gap was 0.75 eV while the density of states reveals that the O 2p (the top valence band and Zn 4s (the bottom conduction band states domination.

  13. Anxiety and health problems related to air travel.

    Science.gov (United States)

    McIntosh, I B; Swanson, V; Power, K G; Raeside, F; Dempster, C

    1998-12-01

    A significant proportion of air travelers experience situational anxiety and physical health problems. Take-off and landing are assumed to be stressful, but anxiety related to other aspects of the air travel process, anxiety coping strategies, and in-flight health problems have not previously been investigated. We aimed to investigate frequency of perceived anxiety at procedural stages of air travel, individual strategies used to reduce such anxiety, and frequency of health problems on short-haul and long-haul flights. A questionnaire measuring the occurrence and frequency of the above was administered to two samples of intending travelers during a 3 month period to: (a) 138 travel agency clients, and (b) 100 individuals attending a hospital travel clinic. Of the 238 respondents, two thirds were women. Take-off and landing were a perceived source of anxiety for about 40% of respondents, flight delays for over 50%, and customs and baggage reclaim for a third of individuals. Most frequent anxiety-reduction methods included alcohol and cigarette use, and distraction or relaxation techniques. Physical health problems related to air travel were common, and there was a strong relationship between such problems and frequency of anxiety. Travel agency clients reported more anxiety but not more physical health symptoms overall than travel clinic clients. Women reported greater air-travel anxiety, and more somatic symptoms than men. Significant numbers of air travelers report perceived anxiety related to aspects of travel, and this is associated with health problems during flights. Airlines and travel companies could institute specific measures, including improved information and communication, to reassure clients and thereby diminish anxiety during stages of air-travel. Medical practitioners and travel agencies should also be aware of the potential stresses of air travel and the need for additional information and advice.

  14. Calculation of the backscattering in water and compared to the values in air; Calculo del factor de retrodispersion en agua y comparativa con los valores en aire

    Energy Technology Data Exchange (ETDEWEB)

    Minano Herrero, J. A.; Sarasa Rubio, A.; Roldan Arjona, J. M.

    2011-07-01

    The purpose of this paper is to calculate values of BSF in water and comparison with data on air 11SF found in the literature. For this simulations have been performed by the Monte Carlo method for calculating values ??kerma water in the presence of a manikin of this material and in the absence thereof. The simulations were performed for monoenergetic beams in order to facilitate the calculation of the BSF for any spectral distribution of those found in the field of radiology.

  15. Relating water and air flow characteristics in coarse granular materials

    DEFF Research Database (Denmark)

    Andreasen, Rune Røjgaard; Canga, Eriona; Poulsen, Tjalfe Gorm

    2013-01-01

    Water pressure drop as a function of velocity controls w 1 ater cleaning biofilter operation 2 cost. At present this relationship in biofilter materials must be determined experimentally as no 3 universal link between pressure drop, velocity and filter material properties have been established. 4...... Pressure drop - velocity in porous media is much simpler and faster to measure for air than for water. 5 For soils and similar materials, observations show a strong connection between pressure drop – 6 velocity relations for air and water, indicating that water pressure drop – velocity may be estimated 7...... from air flow data. The objective of this study was, therefore, to investigate if this approach is valid 8 also for coarse granular biofilter media which usually consists of much larger particles than soils. In 9 this paper the connection between the pressure drop – velocity relationships for air...

  16. Tolerance Levels of Roadside Trees to Air Pollutants Based on Relative Growth Rate and Air Pollution Tolerance Index

    Directory of Open Access Journals (Sweden)

    SULISTIJORINI

    2008-09-01

    Full Text Available Motor vehicles release carbon monoxide, nitrogen dioxide, sulphur dioxide, and particulate matters to the air as pollutants. Vegetation can absorb these pollutants through gas exchange processes. The objective of this study was to examine the combination of the relative growth rate (RGR and physiological responses in determining tolerance levels of plant species to air pollutants. Physiological responses were calculated as air pollution tolerance index (APTI. Eight roadside tree species were placed at polluted (Jagorawi highway and unpolluted (Sindangbarang field area. Growth and physiological parameters of the trees were recorded, including plant height, leaf area, total ascorbate, total chlorophyll, leaf-extract pH, and relative water content. Scoring criteria for the combination of RGR and APTI method was given based on means of the two areas based on two-sample t test. Based on the total score of RGR and APTI, Lagerstroemia speciosa was categorized as a tolerant species; and Pterocarpus indicus, Delonix regia, Swietenia macrophylla were categorized as moderately tolerant species. Gmelina arborea, Cinnamomum burmanii, and Mimusops elengi were categorized as intermediate tolerant species. Lagerstroemia speciosa could be potentially used as roadside tree. The combination of RGR and APTI value was better to determinate tolerance level of plant to air pollutant than merely APTI method.

  17. A relation between calculated human body exergy consumption rate and subjectively assessed thermal sensation

    Energy Technology Data Exchange (ETDEWEB)

    Simone, Angela; Kolarik, Jakub; Olesen, Bjarne W. [ICIEE/BYG, Technical University of Denmark (Denmark); Iwamatsu, Toshiya [Faculty of Urban Environmental Science, Tokyo Metropolitan University (Japan); Asada, Hideo [Architech Consulting Co., Tokyo (Japan); Dovjak, Mateja [Faculty of Civil and Geodetic Engineering, University of Ljubljana (Slovenia); Schellen, Lisje [Eindhoven University of Technology, Faculty of Architecture Building and Planning (Netherlands); Shukuya, Masanori [Laboratory of Building Environment, Tokyo City University, Yokohama (Japan)

    2011-01-15

    Application of the exergy concept to research on the built environment is a relatively new approach. It helps to optimize climate conditioning systems so that they meet the requirements of sustainable building design. As the building should provide a healthy and comfortable environment for its occupants, it is reasonable to consider both the exergy flows in building and those within the human body. Until now, no data have been available on the relation between human-body exergy consumption rates and subjectively assessed thermal sensation. The objective of the present work was to relate thermal sensation data, from earlier thermal comfort studies, to calculated human-body exergy consumption rates. The results show that the minimum human body exergy consumption rate is associated with thermal sensation votes close to thermal neutrality, tending to the slightly cool side of thermal sensation. Generally, the relationship between air temperature and the exergy consumption rate, as a first approximation, shows an increasing trend. Taking account of both convective and radiative heat exchange between the human body and the surrounding environment by using the calculated operative temperature, exergy consumption rates increase as the operative temperature increases above 24 C or decreases below 22 C. With the data available so far, a second-order polynomial relationship between thermal sensation and the exergy consumption rate was established. (author)

  18. Comparison and application study on cosmic radiation dose calculation received by air crew

    International Nuclear Information System (INIS)

    Zhou Qiang; Xu Cuihua; Ren Tianshan; Li Wenhong; Zhang Jing; Lu Xu

    2009-01-01

    Objective: To facilitate evaluation on Cosmic radiation dose received by flight crew by developing a convenient and effective measuring method. Methods: In comparison with several commonly used evaluating methods, this research employs CARI-6 software issued by FAA (Federal Aviation Administration) to measure Cosmic radiation dose for flight crew members exposed to. Results: Compared with other methods, CARI-6 is capable of providing reliable calculating results on radiation dose and applicable to all flight crew of different airlines. Conclusion: Cosmic radiation received by flight crew is on the list of occupational radiation. For a smooth running of Standards for controlling exposure to cosmic radiation of air crew, CARI software may be a widely applied tool in radiation close estimation of for flight crew. (authors)

  19. Calculated neutron air kerma strength conversion factors for a generically encapsulated Cf-252 brachytherapy source

    CERN Document Server

    Rivard, M J; D'Errico, F; Tsai, J S; Ulin, K; Engler, M J

    2002-01-01

    The sup 2 sup 5 sup 2 Cf neutron air kerma strength conversion factor (S sub K sub N /m sub C sub f) is a parameter needed to convert the radionuclide mass (mu g) provided by Oak Ridge National Laboratory into neutron air kerma strength required by modern clinical brachytherapy dosimetry formalisms indicated by Task Group No. 43 of the American Association of Physicists in Medicine (AAPM). The impact of currently used or proposed encapsulating materials for sup 2 sup 5 sup 2 Cf brachytherapy sources (Pt/Ir-10%, 316L stainless steel, nitinol, and Zircaloy-2) on S sub K sub N /m sub C sub f was calculated and results were fit to linear equations. Only for substantial encapsulation thicknesses, did S sub K sub N /m sub C sub f decrease, while the impact of source encapsulation composition is increasingly negligible as Z increases. These findings are explained on the basis of the non-relativistic kinematics governing the majority of sup 2 sup 5 sup 2 Cf neutron interactions. Neutron kerma and energy spectra resul...

  20. Traffic-Related Air Pollution and Parkinson's Disease in Denmark

    DEFF Research Database (Denmark)

    Ritz, Beate; Lee, Pei-Chen; Hansen, Johnni

    2016-01-01

    -related air pollution and Parkinson's disease. METHODS: In a case-control study of 1,696 Parkinson's disease (PD) patients identified from Danish hospital registries and diagnosed 1996-2009 and 1,800 population controls matched by gender and year of birth we assessed long-term traffic-related air pollutant...... exposures (NO2) from a dispersion model, using residential addresses from 1971 to the date of diagnosis or first cardinal symptom for cases and the corresponding index date for their matched controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated with logistic regression adjusting...

  1. Carcinogenic Air Toxics Exposure and Their Cancer-Related Health Impacts in the United States.

    Directory of Open Access Journals (Sweden)

    Ying Zhou

    Full Text Available Public health protection from air pollution can be achieved more effectively by shifting from a single-pollutant approach to a multi-pollutant approach. To develop such multi-pollutant approaches, identifying which air pollutants are present most frequently is essential. This study aims to determine the frequently found carcinogenic air toxics or hazardous air pollutants (HAPs combinations across the United States as well as to analyze the health impacts of developing cancer due to exposure to these HAPs. To identify the most commonly found carcinogenic air toxics combinations, we first identified HAPs with cancer risk greater than one in a million in more than 5% of the census tracts across the United States, based on the National-Scale Air Toxics Assessment (NATA by the U.S. EPA for year 2005. We then calculated the frequencies of their two-component (binary, and three-component (ternary combinations. To quantify the cancer-related health impacts, we focused on the 10 most frequently found HAPs with national average cancer risk greater than one in a million. Their cancer-related health impacts were calculated by converting lifetime cancer risk reported in NATA 2005 to years of healthy life lost or Disability-Adjusted Life Years (DALYs. We found that the most frequently found air toxics with cancer risk greater than one in a million are formaldehyde, carbon tetrachloride, acetaldehyde, and benzene. The most frequently occurring binary pairs and ternary mixtures are the various combinations of these four air toxics. Analysis of urban and rural HAPs did not reveal significant differences in the top combinations of these chemicals. The cumulative annual cancer-related health impacts of inhaling the top 10 carcinogenic air toxics included was about 1,600 DALYs in the United States or 0.6 DALYs per 100,000 people. Formaldehyde and benzene together contribute nearly 60 percent of the total cancer-related health impacts. Our study shows that although

  2. Carcinogenic Air Toxics Exposure and Their Cancer-Related Health Impacts in the United States.

    Science.gov (United States)

    Zhou, Ying; Li, Chaoyang; Huijbregts, Mark A J; Mumtaz, M Moiz

    2015-01-01

    Public health protection from air pollution can be achieved more effectively by shifting from a single-pollutant approach to a multi-pollutant approach. To develop such multi-pollutant approaches, identifying which air pollutants are present most frequently is essential. This study aims to determine the frequently found carcinogenic air toxics or hazardous air pollutants (HAPs) combinations across the United States as well as to analyze the health impacts of developing cancer due to exposure to these HAPs. To identify the most commonly found carcinogenic air toxics combinations, we first identified HAPs with cancer risk greater than one in a million in more than 5% of the census tracts across the United States, based on the National-Scale Air Toxics Assessment (NATA) by the U.S. EPA for year 2005. We then calculated the frequencies of their two-component (binary), and three-component (ternary) combinations. To quantify the cancer-related health impacts, we focused on the 10 most frequently found HAPs with national average cancer risk greater than one in a million. Their cancer-related health impacts were calculated by converting lifetime cancer risk reported in NATA 2005 to years of healthy life lost or Disability-Adjusted Life Years (DALYs). We found that the most frequently found air toxics with cancer risk greater than one in a million are formaldehyde, carbon tetrachloride, acetaldehyde, and benzene. The most frequently occurring binary pairs and ternary mixtures are the various combinations of these four air toxics. Analysis of urban and rural HAPs did not reveal significant differences in the top combinations of these chemicals. The cumulative annual cancer-related health impacts of inhaling the top 10 carcinogenic air toxics included was about 1,600 DALYs in the United States or 0.6 DALYs per 100,000 people. Formaldehyde and benzene together contribute nearly 60 percent of the total cancer-related health impacts. Our study shows that although there are many

  3. The model for calculation of emission and imisson of air pollutants from vehicles with internal combustion engine

    International Nuclear Information System (INIS)

    Tashevski, Done; Dimitrovski, Mile

    1994-01-01

    The model for calculation of emission and immision of air pollutants from vehicles with internal combustion engine on the crossroads in urban environments, with substitution of a great number of exhaust-pipes with one chimney in the centre of the crossroad has been made. The whole calculation of the pollution sources mentioned above is, in the fact, the calculation of the emission and imisson of pollutants from point sources of pollution. (author)

  4. Dose factors to calculate the radiation exposure due to radioactive waste air from nuclear facilities

    International Nuclear Information System (INIS)

    Brenk, H.D.; Vogt, K.J.

    1977-01-01

    An evaluation of the environmental impact of nuclear plants according to paragraph 45 of the Radiation Protection Directive of the Federal Republic of Germany requires the calculation of dose conversion factors indicating the correlation between the contaminated medium and individual radiation exposure. The present study is to be conceived as a contribution to discussion on this subject. For the determination of radiation exposure caused by the waste air of nuclear plants, models are being specified for computing the dose conversion factors for the external exposure pathways of β-submersion, γ-submersion and γ-radiation from contaminated ground as well as the internal exposure pathways of inhalation and ingestion, which further elaborate and improve the models previously applied, especially as far as the ingestion pathway is concerned, which distinguishes between 6 major food categories. The computer models are applied to those radionuclides which are significan for nuclear emitters, in particular nuclear light-water power stations. The results obtained for the individual exposure pathways and affected organs are specified in the form of tables. For this purpose, calculations were first of all carried out for the so-called 'reference man'. The results can be transferred to population groups with different consumption habits (e.g. vegetarians) by the application of correction factors. The models are capable of being extended with a view to covering other age groups. (orig.) [de

  5. MO-D-213-07: RadShield: Semi- Automated Calculation of Air Kerma Rate and Barrier Thickness

    International Nuclear Information System (INIS)

    DeLorenzo, M; Wu, D; Rutel, I; Yang, K

    2015-01-01

    Purpose: To develop the first Java-based semi-automated calculation program intended to aid professional radiation shielding design. Air-kerma rate and barrier thickness calculations are performed by implementing NCRP Report 147 formalism into a Graphical User Interface (GUI). The ultimate aim of this newly created software package is to reduce errors and improve radiographic and fluoroscopic room designs over manual approaches. Methods: Floor plans are first imported as images into the RadShield software program. These plans serve as templates for drawing barriers, occupied regions and x-ray tube locations. We have implemented sub-GUIs that allow the specification in regions and equipment for occupancy factors, design goals, number of patients, primary beam directions, source-to-patient distances and workload distributions. Once the user enters the above parameters, the program automatically calculates air-kerma rate at sampled points beyond all barriers. For each sample point, a corresponding minimum barrier thickness is calculated to meet the design goal. RadShield allows control over preshielding, sample point location and material types. Results: A functional GUI package was developed and tested. Examination of sample walls and source distributions yields a maximum percent difference of less than 0.1% between hand-calculated air-kerma rates and RadShield. Conclusion: The initial results demonstrated that RadShield calculates air-kerma rates and required barrier thicknesses with reliable accuracy and can be used to make radiation shielding design more efficient and accurate. This newly developed approach differs from conventional calculation methods in that it finds air-kerma rates and thickness requirements for many points outside the barriers, stores the information and selects the largest value needed to comply with NCRP Report 147 design goals. Floor plans, parameters, designs and reports can be saved and accessed later for modification and recalculation

  6. MO-D-213-07: RadShield: Semi- Automated Calculation of Air Kerma Rate and Barrier Thickness

    Energy Technology Data Exchange (ETDEWEB)

    DeLorenzo, M [Oklahoma University Health Sciences Center, Oklahoma City, OK (United States); Wu, D [University of Oklahoma Health Sciences Center, Oklahoma City, Ok (United States); Rutel, I [University of Oklahoma Health Science Center, Oklahoma City, OK (United States); Yang, K [Massachusetts General Hospital, Boston, MA (United States)

    2015-06-15

    Purpose: To develop the first Java-based semi-automated calculation program intended to aid professional radiation shielding design. Air-kerma rate and barrier thickness calculations are performed by implementing NCRP Report 147 formalism into a Graphical User Interface (GUI). The ultimate aim of this newly created software package is to reduce errors and improve radiographic and fluoroscopic room designs over manual approaches. Methods: Floor plans are first imported as images into the RadShield software program. These plans serve as templates for drawing barriers, occupied regions and x-ray tube locations. We have implemented sub-GUIs that allow the specification in regions and equipment for occupancy factors, design goals, number of patients, primary beam directions, source-to-patient distances and workload distributions. Once the user enters the above parameters, the program automatically calculates air-kerma rate at sampled points beyond all barriers. For each sample point, a corresponding minimum barrier thickness is calculated to meet the design goal. RadShield allows control over preshielding, sample point location and material types. Results: A functional GUI package was developed and tested. Examination of sample walls and source distributions yields a maximum percent difference of less than 0.1% between hand-calculated air-kerma rates and RadShield. Conclusion: The initial results demonstrated that RadShield calculates air-kerma rates and required barrier thicknesses with reliable accuracy and can be used to make radiation shielding design more efficient and accurate. This newly developed approach differs from conventional calculation methods in that it finds air-kerma rates and thickness requirements for many points outside the barriers, stores the information and selects the largest value needed to comply with NCRP Report 147 design goals. Floor plans, parameters, designs and reports can be saved and accessed later for modification and recalculation

  7. Motor vehicle-related air toxics study. Final report

    International Nuclear Information System (INIS)

    1993-04-01

    Section 202 (1)(1) of the Clean Air Act (CAA), as amended (Section 206 of the Clean Air Act Amendments) (CAAA) of 1990 added paragraph (1) to Section 202 of the (CAA), directs the Environmental Protection Agency (EPA) to complete a study by May 15, 1992 of the need for, and feasibility of, controlling emissions of toxic air pollutants which are unregulated under the Act and associated with motor vehicles and motor vehicle fuels. The report has been prepared in response to Section 202 (1)(1). Specific pollutants or pollutant categories which are discussed in the report include benezene, formaldehyde, 1,3-butadiene, acetaldehyde, diesel particulate matter, gasoline particulate matter, and gasoline vapors as well as certain of the metals and motor vehicle-related pollutants identified in Section 112 of the Clean Air Act. The focus of the report is on carcinogenic risk. The study attempts to summarize what is known about motor vehicle-related air toxics and to present all significant scientific opinion on each issue

  8. EPA activities related to emerging air sensor technology

    Science.gov (United States)

    This slide set was developed through contributions of NERL and NRMRL research groups and organized to explain the diversity of ongoing research related to emerging air sensor technology for an international audience. Gayle will be walking OAQPS through the slide set in advance o...

  9. Traffic-related air pollution and spectacles use in schoolchildren

    NARCIS (Netherlands)

    Dadvand, Payam; Nieuwenhuijsen, Mark J; Basagaña, Xavier; Alvarez-Pedrerol, Mar; Dalmau-Bueno, Albert; Cirach, Marta; Rivas, Ioar; Brunekreef, Bert; Querol, Xavier; Morgan, Ian G; Sunyer, Jordi

    2017-01-01

    PURPOSE: To investigate the association between exposure to traffic-related air pollution and use of spectacles (as a surrogate measure for myopia) in schoolchildren. METHODS: We analyzed the impact of exposure to NO2 and PM2.5 light absorbance at home (predicted by land-use regression models) and

  10. The impact of draught related to air velocity, air temperature and workload.

    Science.gov (United States)

    Griefahn, B; Künemund, C; Gehring, U

    2001-08-01

    This experimental study was designed to test the hypotheses that the effects of draught increase with higher air velocity, with lower air temperature, and with lower workload. Thirty healthy young males were exposed to horizontal draught during 55 min while they operated an arm ergometer in a standing posture. Air velocity, air temperature, and workload were varied in 3 steps each, between 11 and 23 degrees C, 0.1 and 0.3 m/s, and 104 to 156 W/m2, respectively. The 27 combinations were distributed over subjects in a fractional factorial 3(3)-design. The participants were clothed for thermal neutrality. Workload was measured at the end of the sessions by respirometry. Draught-induced annoyance was determined every 5 min, separately for 10 body sites. Corresponding skin temperature was also recorded. The hypotheses were verified for the influence of air velocity and air temperature. Regarding workload, local heat production is probably decisive, meaning that draft-induced local annoyance is inversely related to workload in active but independent from workload in non-active body areas. To improve the situation for the workers concerned it is suggested to apply protective gloves that cover an as great area of the forearms as possible and to limit airflows to mean velocities of less than 0.2 m/s (with turbulence intensities of 50%).

  11. Method of Relative Magnitudes for Calculating Magnetic Fluxes in Electrical Machine

    Directory of Open Access Journals (Sweden)

    Oleg A.

    2018-03-01

    Full Text Available Introduction: The article presents the study results of the model of an asynchronous electric motor carried out by the author within the framework of the Priorities Research Program “Research and development in the priority areas of development of Russia’s scientific and technical complex for 2014–2020”. Materials and Methods: A model of an idealized asynchronous machine (with sinusoidal distribution of magnetic induction in air gap is used in vector control systems. It is impossible to create windings for this machine. The basis of the new calculation approach was the Conductivity of Teeth Contours Method, developed at the Electrical Machines Chair of the Moscow Power Engineering Institute (MPEI. Unlike this method, the author used not absolute values, but relative magnitudes of magnetic fluxes. This solution fundamentally improved the method’s capabilities. The relative magnitudes of the magnetic fluxes of the teeth contours do not required the additional consideration for exact structure of magnetic field of tooth and adjacent slots. These structures are identical for all the teeth of the machine and differ only in magnitude. The purpose of the calculations was not traditional harmonic analysis of magnetic induction distribution in air gap of machine, but a refinement of the equations of electric machine model. The vector control researchers used only the cos(θ function as a value of mutual magnetic coupling coefficient between the windings. Results: The author has developed a way to take into account the design of the windings of a real machine by using imaginary measuring winding with the same winding design as a real phase winding. The imaginary winding can be placed in the position of any machine windings. The calculation of the relative magnetic fluxes of this winding helped to estimate the real values of the magnetic coupling coefficients between the windings, and find the correction functions for the model of an idealized

  12. Integration of air quality-related planning processes : report

    International Nuclear Information System (INIS)

    2004-05-01

    Several communities in British Columbia have conducted air quality, greenhouse gas, or community energy management plans. This report explored the possibility of integrating 3 community-based air quality-related planning processes into a single process and evaluated the use of these 3 processes by local governments and First Nations in identifying and addressing air quality-related objectives, and determined to what extent they could be integrated to achieve planning objectives for air quality, greenhouse gas emissions, and energy supply and conservation. The lessons learned from 9 case studies in British Columbia were presented. The purpose of the case studies was to examine how communities handled emissions and energy related inventory and planning work, as well as their experiences with, or considerations for, an integrated process. The lessons were grouped under several key themes including organization and stakeholder involvement; messaging and focus; leadership/champions; and resources and capacity. The report also outlined a framework for an integrated planning process and provided recommendations regarding how an integrated or complementary process could be performed. A number of next steps were also offered for the provincial government to move the concept of an integrated process forward with the assistance of other partners. These included identifying the resources required to support communities engaging in an integrated process as well as discussing the series of options for provincial support with key stakeholders. refs., tabs., figs

  13. Geospatial Modeling of Asthma Population in Relation to Air Pollution

    Science.gov (United States)

    Kethireddy, Swatantra R.; Tchounwou, Paul B.; Young, John H.; Luvall, Jeffrey C.; Alhamdan, Mohammad

    2013-01-01

    Current observations indicate that asthma is growing every year in the United States, specific reasons for this are not well understood. This study stems from an ongoing research effort to investigate the spatio-temporal behavior of asthma and its relatedness to air pollution. The association between environmental variables such as air quality and asthma related health issues over Mississippi State are investigated using Geographic Information Systems (GIS) tools and applications. Health data concerning asthma obtained from Mississippi State Department of Health (MSDH) for 9-year period of 2003-2011, and data of air pollutant concentrations (PM2.5) collected from USEPA web resources, and are analyzed geospatially to establish the impacts of air quality on human health specifically related to asthma. Disease mapping using geospatial techniques provides valuable insights into the spatial nature, variability, and association of asthma to air pollution. Asthma patient hospitalization data of Mississippi has been analyzed and mapped using quantitative Choropleth techniques in ArcGIS. Patients have been geocoded to their respective zip codes. Potential air pollutant sources of Interstate highways, Industries, and other land use data have been integrated in common geospatial platform to understand their adverse contribution on human health. Existing hospitals and emergency clinics are being injected into analysis to further understand their proximity and easy access to patient locations. At the current level of analysis and understanding, spatial distribution of Asthma is observed in the populations of Zip code regions in gulf coast, along the interstates of south, and in counties of Northeast Mississippi. It is also found that asthma is prevalent in most of the urban population. This GIS based project would be useful to make health risk assessment and provide information support to the administrators and decision makers for establishing satellite clinics in future.

  14. Calculation of conversion factor of Kerma in the air for ambient dose equivalent in radiotherapy

    International Nuclear Information System (INIS)

    Lima, Marco Antonio Frota

    2000-03-01

    This work aims to estimate the average conversion factor of Kerma in air to H * (10) using photon beams coming from clinic linear accelerators, transmitted through concrete walls of a radiotherapic treatment room. The transmitted photon spectra by both 1 meter and 2 meters concrete walls, in an area of 40 x 40 cm 2 , were calculated when the primary beam impart in an angle of 0 deg. The (secondary) photon beams transmitted respectively by 0,5 meter, 1,0 meter, 1,0 meter and 2,0 meter concrete walls, after they scattered by an angle of 90 deg in a cylindric phantom inside the room, were also determined. Generally, 50 millions of histories were computed for each simulation made for the primary beam. For the 90 deg spread, the number of histories was 100 millions. The computational code used on this work was the MCNP4B. The most common clinic accelerators used on radiotheraphic treatments were used on this work CLINAC-4, CLINAC-6, CLINAC-18 and CLINAC-2500. From the spectra analysis obtained in this work, it was possible to dispose the conversion factor for realistic beams found in radiotherapeutic establishment. (author)

  15. Air-over-ground calculations of the neutron, prompt, and secondary-gamma free-in-air tissue kerma from the Hiroshima and Nagasaki devices

    International Nuclear Information System (INIS)

    Pace, J.V. III; Knight, J.R.; Bartine, D.E.

    1982-01-01

    This paper reports preliminary results of the two-dimensional discrete-ordinate, calculations for the air-over-ground transport of radiation from the Hiroshima and Nagasaki weapon devices. It was found that the gamma-ray kerma dominated the total kerma for both environments

  16. Hot-wire air flow meter for gasoline fuel-injection system. Calculation of air mass in cylinder during transient condition; Gasoline funsha system yo no netsusenshiki kuki ryuryokei. Kato untenji no cylinder juten kukiryo no keisan

    Energy Technology Data Exchange (ETDEWEB)

    Oyama, Y [Hitachi Car Engineering, Ltd., Tokyo (Japan); Nishimura, Y; Osuga, M; Yamauchi, T [Hitachi, Ltd., Tokyo (Japan)

    1997-10-01

    Air flow characteristics of hot-wire air flow meters for gasoline fuel-injection systems with supercharging and exhaust gas recycle during transient conditions were investigated to analyze a simple method for calculating air mass in cylinder. It was clarified that the air mass in cylinder could be calculated by compensating for the change of air mass in intake system by using aerodynamic models of intake system. 3 refs., 6 figs., 1 tab.

  17. Hair 2010 Documentation: Calculating risk indicators related to agricultural use of pesticides within the European Union

    NARCIS (Netherlands)

    Kruijne, R.; Deneer, J.W.; Lahr, J.; Vlaming, J.

    2011-01-01

    The HAIR instrument calculates risk indicators related to the agricultural use of pesticides in EU Member States. HAIR combines databases and models for calculating potential environmental environmental effects expressed by the exposure toxicity ratio.

  18. Monitoring of air pollution levels related to Charilaos Trikoupis Bridge.

    Science.gov (United States)

    Sarigiannis, D A; Handakas, E J; Kermenidou, M; Zarkadas, I; Gotti, A; Charisiadis, P; Makris, K; Manousakas, M; Eleftheriadis, K; Karakitsios, S P

    2017-12-31

    Charilaos Trikoupis bridge is the longest cable bridge in Europe that connects Western Greece with the rest of the country. In this study, six air pollution monitoring campaigns (including major regulated air pollutants) were carried out from 2013 to 2015 at both sides of the bridge, located in the urban areas of Rio and Antirrio respectively. Pollution data were statistically analyzed and air quality was characterized using US and European air quality indices. From the overall campaign, it was found that air pollution levels were below the respective regulatory thresholds, but once at the site of Antirrio (26.4 and 52.2μg/m 3 for PM 2.5 and ΡΜ 10 , respectively) during the 2nd winter period. Daily average PM 10 and PM 2.5 levels from two monitoring sites were well correlated to gaseous pollutant (CO, NO, NO 2 , NO x and SO 2 ) levels, meteorological parameters and factor scores from Positive Matrix Factorization during the 3-year period. Moreover, the elemental composition of PM 10 and PM 2.5 was used for source apportionment. That analysis revealed that major emission sources were sulfates, mineral dust, biomass burning, sea salt, traffic and shipping emissions for PM 10 and PM 2.5 , for both Rio and Antirrio. Seasonal variation indicates that sulfates, mineral dust and traffic emissions increased during the warm season of the year, while biomass burning become the dominant during the cold season. Overall, the contribution of the Charilaos Trikoupis bridge to the vicinity air pollution is very low. This is the result of the relatively low daily traffic volume (~10,000 vehicles per day), the respective traffic fleet composition (~81% of the traffic fleet are private vehicles) and the speed limit (80km/h) which does not favor traffic emissions. In addition, the strong and frequent winds further contribute to the rapid dispersion of the emitted pollutants. Copyright © 2017. Published by Elsevier B.V.

  19. Unpaid ecological costs related to emissions in the air

    International Nuclear Information System (INIS)

    Moreau, Sylvain; Bottin, Anne; Nauroy, Frederic; Boitard, Corinne; Bird, Geoffrey; David, Michel; Greffet, Pierre; Mordant, Guillaume; Moreau, Sylvain; Nirascou, Francoise; Le Moullec, Aurelie; Berthier, Jean-Pierre; Hassan, Marie-Elizabeth; Curri-Lemaitre, Elen; Lagarenne, Christine; Devaux, Jeremy; Nicklaus, Doris; Puydarrieux, Philippe; Vanoli, Andre; Schucht, Simone

    2014-05-01

    This study proposes an analysis of unpaid ecological terms based on the use of new economic indicators related to sustainable development (going beyond the GDP, adjusted accounting aggregates, accounting unpaid ecological costs), an analysis of unpaid ecological costs related to climate change (context, used results and data, definitions of trajectories associated with greenhouse gas emissions, cost to be applied to emissions to get rid of, assessment of unpaid ecological costs), and an analysis of unpaid ecological costs related to air pollution (objectives, standard to be adopted, towards more ambitious emission reduction and re-assessed costs, unpaid ecological costs in 2010)

  20. SU-E-T-339: Dosimetric Verification of Acuros XB Dose Calculation Algorithm On An Air Cavity for 6-MV Flattening Filter-Free Beam

    International Nuclear Information System (INIS)

    Kang, S; Suh, T; Chung, J

    2015-01-01

    Purpose: This study was to verify the accuracy of Acuros XB (AXB) dose calculation algorithm on an air cavity for a single radiation field using 6-MV flattening filter-free (FFF) beam. Methods: A rectangular slab phantom containing an air cavity was made for this study. The CT images of the phantom for dose calculation were scanned with and without film at measurement depths (4.5, 5.5, 6.5 and 7.5 cm). The central axis doses (CADs) and the off-axis doses (OADs) were measured by film and calculated with Analytical Anisotropic Algorithm (AAA) and AXB for field sizes ranging from 2 Χ 2 to 5 Χ 5 cm 2 of 6-MV FFF beams. Both algorithms were divided into AXB-w and AAA -w when included the film in phantom for dose calculation, and AXB-w/o and AAA-w/o in calculation without film. The calculated OADs for both algorithms were compared with the measured OADs and difference values were determined using root means squares error (RMSE) and gamma evaluation. Results: The percentage differences (%Diffs) between the measured and calculated CAD for AXB-w was most agreement than others. Compared to the %Diff with and without film, the %Diffs with film were decreased than without within both algorithms. The %Diffs for both algorithms were reduced with increasing field size and increased relative to the depth increment. RMSEs of CAD for AXB-w were within 10.32% for both inner-profile and penumbra, while the corresponding values of AAA-w appeared to 96.50%. Conclusion: This study demonstrated that the dose calculation with AXB within air cavity shows more accurate than with AAA compared to the measured dose. Furthermore, we found that the AXB-w was superior to AXB-w/o in this region when compared against the measurements

  1. Cooling load calculations of radiant and all-air systems for commercial buildings

    DEFF Research Database (Denmark)

    Bourdakis, Eleftherios; Bauman, Fred; Schiavon, Stefano

    The authors simulated in TRNSYS three radiant systems coupled with a 50% sized variable air volume (VAV) system and a 50% sized all-air VAV system with night ventilation. The objective of this study was to identify the differences in the cooling load profiles of the examined systems when they are......The authors simulated in TRNSYS three radiant systems coupled with a 50% sized variable air volume (VAV) system and a 50% sized all-air VAV system with night ventilation. The objective of this study was to identify the differences in the cooling load profiles of the examined systems when...

  2. Tracking air-related health should be an integrated part of air quality management in South Africa

    CSIR Research Space (South Africa)

    Wright, CY

    2010-09-01

    Full Text Available that the largest burden of air pollution related diseases is on developing countries where air pollution levels are also among the highest in the world. Air pollution may cause symptoms ranging from eyes, nose and throat irritation, exacerbation of asthma...

  3. Area balance method for calculation of air interchange in fire-resesistance testing laboratory for building products and constructions

    Directory of Open Access Journals (Sweden)

    Sargsyan Samvel Volodyaevich

    2014-09-01

    Full Text Available Fire-resistance testing laboratory for building products and constructions is a production room with a substantial excess heat (over 23 W/m . Significant sources of heat inside the aforementioned laboratory are firing furnace, designed to simulate high temperature effects on structures and products of various types in case of fire development. The excess heat production in the laboratory during the tests is due to firing furnaces. The laboratory room is considered as an object consisting of two control volumes (CV, in each of which there may be air intake and air removal, pollutant absorption or emission. In modeling air exchange conditions the following processes are being considered: the processes connected with air movement in the laboratory room: the jet stream in a confined space, distribution of air parameters, air motion and impurity diffusion in the ventilated room. General upward ventilation seems to be the most rational due to impossibility of using local exhaust ventilation. It is connected with the peculiarities of technological processes in the laboratory. Air jets spouted through large-perforated surface mounted at the height of 2 m from the floor level, "flood" the lower control volume, entrained by natural convective currents from heat sources upward and removed from the upper area. In order to take advantage of the proposed method of the required air exchange calculation, you must enter additional conditions, taking into account the provision of sanitary-hygienic characteristics of the current at the entrance of the service (work area. Exhaust air containing pollutants (combustion products, is expelled into the atmosphere by vertical jet discharge. Dividing ventilated rooms into two control volumes allows describing the research process in a ventilated room more accurately and finding the air exchange in the lab room during the tests on a more reasonable basis, allowing to provide safe working conditions for the staff without

  4. Traffic-related particulate air pollution exposure in urban areas

    Science.gov (United States)

    Borrego, C.; Tchepel, O.; Costa, A. M.; Martins, H.; Ferreira, J.; Miranda, A. I.

    In the last years, there has been an increase of scientific studies confirming that long- and short-term exposure to particulate matter (PM) pollution leads to adverse health effects. The development of a methodology for the determination of accumulated human exposure in urban areas is the main objective of the current work, combining information on concentrations at different microenvironments and population time-activity pattern data. A link between a mesoscale meteorological and dispersion model and a local scale air quality model was developed to define the boundary conditions for the local scale application. The time-activity pattern of the population was derived from statistical information for different sub-population groups and linked to digital city maps. Finally, the hourly PM 10 concentrations for indoor and outdoor microenvironments were estimated for the Lisbon city centre, which was chosen as the case-study, based on the local scale air quality model application for a selected period. This methodology is a first approach to estimate population exposure, calculated as the total daily values above the thresholds recommended for long- and short-term health effects. Obtained results reveal that in Lisbon city centre a large number of persons are exposed to PM levels exceeding the legislated limit value.

  5. Health effects from air pollution - calculation prices; Sundhedseffekter af luftforurening - beregningspriser

    Energy Technology Data Exchange (ETDEWEB)

    Skou Andersen, Mikael; Seested Nielsen, Jytte; Borgen Soerensen, Peter [DMU, Afdeling for Systemanalyse, Roskilde (Denmark); Frohn, Lise Marie; Solvang Jensen, Steen; Hertel, Ole; Brandt, Joergen; Christensen, Jesper [DMU, Afdeling for Atmosfaerisk Miljoe, Roskilde (Denmark)

    2004-10-01

    The basic aim of research focusing on the accounting of external effects is to provide estimates for the possible benefits of environmental policy projects. There is a demand within the field of environmental economic analysis for evaluations and estimates of the economic benefits arising from pollution reductions. Where benefits arising out of reduced emissions of harmful substances are concerned, these can be estimated according to the avoided damage costs associated with negative pollution impacts. A scientifically based method designed for this purpose has been developed in the pan-European ExternE project via the EU research programmes. The ExternE project has been implemented with the aim of estimating monetary values for externalities attached to air pollution accruing from energy production and transport. For this purpose, complex model-based environmental impact estimations have been coupled with corresponding monetary valuations via the modelling tool, Ecosense. A problem arising in relation to Ecosense methodology has been that externalities are often of local nature - pollution impact depending on the particular locality of the emission and dispersal characteristics in the surrounding environment. Therefore, the economic estimation of the impacts of pollution is based on a location-specific modelling system. (BA)

  6. Product-related emissions of Mercury to Air in the European Union

    Energy Technology Data Exchange (ETDEWEB)

    Kindbom, Karin; Munthe, John

    2007-06-15

    Mercury emissions to air from the use of mercury in products have been estimated for the EU for the year 2005. The consumption of mercury in the EU in 2005 was amounted to 125 tonnes in technical products. Estimates of emissions of mercury from dental amalgam were derived from information on cremations in European countries and average contents of amalgam fillings. Annual emissions of mercury to air from product use in EU27 have been estimated to be in the range 10-18 tonnes (best estimate 14 tonnes) from technical products and to 2-5 tonnes from cremation, in total 12-23 tonnes. Of the mercury consumed in technical products, 11% was calculated to be emitted to air, 31% to end up in safe storage while 58% would still be accumulated in society or disposed of in landfills. From the share still accumulated in society, as well as from the already land filled amounts, further emissions of mercury to air may occur in the longer term. Emissions from technical products are calculated based on the consumption of mercury in 2005. Emissions occurring in the same year but caused by consumption in the previous 10 years were derived using the consumption in 2005 and assuming the same patterns of distribution and emissions. The latest available estimates of total anthropogenic emissions of mercury in EU27 refer to the year 2000 and are in the order of 140-190 tonnes, probably to have declined to 2005. Based on these figures the contribution to anthropogenic mercury emissions to air in EU from product use and cremation in 2005 is at least 6-16%. In a previous report product related air emissions of 72 tonnes were estimated for Europe in the mid 1990s, corresponding to 18% of the total air emissions. A significant decrease of emissions has thus occurred which is in line with a decreasing use of mercury in technical products, more efficient collection of remaining products and better emission control. However, the calculations show that the use of mercury in products still

  7. Relative air temperature analysis external building on Gowa Campus

    Science.gov (United States)

    Mustamin, Tayeb; Rahim, Ramli; Baharuddin; Jamala, Nurul; Kusno, Asniawaty

    2018-03-01

    This study aims to data analyze the relative temperature and humidity of the air outside the building. Data retrieval taken from weather monitoring device (monitoring) Vaisala, RTU (Remote Terminal Unit), Which is part of the AWS (Automatic Weather Stations) Then Processing data processed and analyzed by using Microsoft Excel program in the form of graph / picture fluctuation Which shows the average value, standard deviation, maximum value, and minimum value. Results of data processing then grouped in the form: Daily, and monthly, based on time intervals every 30 minutes. The results showed Outside air temperatures in March, April, May and September 2016 Which entered in the thermal comfort zone according to SNI standard (Indonesian National Standard) only at 06.00-10.00. In late March to early April Thermal comfort zone also occurs at 15.30-18.00. The highest maximum air temperature occurred in September 2016 at 11.01-11.30 And the lowest minimum value in September 2016, time 6:00 to 6:30. The result of the next analysis shows the level of data conformity with thermal comfort zone based on SNI (Indonesian National Standard) every month.

  8. Integrating air-related health surveillance into air quality management: perceptions and practicalities

    CSIR Research Space (South Africa)

    Wright, C

    2012-06-01

    Full Text Available Health surveillance is presently not an integral part of air quality management in South Africa, although ambient air pollution standards are derived from health effects of personal exposure. In a survey to air quality officials and environmental...

  9. Traffic-related air pollution - the health effects scrutinized

    NARCIS (Netherlands)

    Nijland, M.E.

    2013-01-01

    Numerous studies have been published on the health effects associated with exposure to air pollution. Air pollution is acknowledged as a public health risk and air quality regulations are set for specific air pollutants to protect human health. A major pollutant, well known for its adverse health

  10. Calculation and measurement of a neutral air flow velocity impacting a high voltage capacitor with asymmetrical electrodes

    Directory of Open Access Journals (Sweden)

    M. Malík

    2014-01-01

    Full Text Available This paper deals with the effects surrounding phenomenon of a mechanical force generated on a high voltage asymmetrical capacitor (the so called Biefeld-Brown effect. A method to measure this force is described and a formula to calculate its value is also given. Based on this the authors derive a formula characterising the neutral air flow velocity impacting an asymmetrical capacitor connected to high voltage. This air flow under normal circumstances lessens the generated force. In the following part this velocity is measured using Particle Image Velocimetry measuring technique and the results of the theoretically calculated velocity and the experimentally measured value are compared. The authors found a good agreement between the results of both approaches.

  11. Valuation of social and health effects of transport-related air pollution in Madrid (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Monzon, Andres; Guerrero, Maria-Jose [Transport Department, Universidad Politecnica de Madrid, Escuela Tecnica Superior de Ingenieros de Caminos, C. y P., Caminos, Ciudad Universitaria, s/n, 28040 Madrid (Spain)

    2004-12-01

    Social impacts of pollutants from mobile sources are a key element in urban design and traffic planning. One of the most relevant impacts is health effects associated with high pollution periods. Madrid is a city that suffers chronic congestion levels and some periods of very stable atmospheric conditions; as a result, pollution levels exceed air quality standards for certain pollutants.This paper focuses on the social evaluation of transport-related emissions. A new methodology to evaluate those impacts in monetary terms has been designed and applied to Madrid. The method takes into account costs associated with losses in working time, mortality and human suffering; calculated using an impact pathway approach linked to CORINAIR emissions. This also allows the calculation of social costs associated with greenhouse gas impacts. As costs have been calculated individually by effect and mode of transport, they can be used to design pricing policies based on real social costs. This paper concludes that the health and social costs of transport-related air pollution in Madrid is 357 Meuro. In these circumstances, the recent public health tax applied in Madrid is clearly correct and sensible with a fair pricing policy on car use.

  12. Valuation of social and health effects of transport-related air pollution in Madrid (Spain)

    International Nuclear Information System (INIS)

    Monzon, Andres; Guerrero, Maria-Jose

    2004-01-01

    Social impacts of pollutants from mobile sources are a key element in urban design and traffic planning. One of the most relevant impacts is health effects associated with high pollution periods. Madrid is a city that suffers chronic congestion levels and some periods of very stable atmospheric conditions; as a result, pollution levels exceed air quality standards for certain pollutants. This paper focuses on the social evaluation of transport-related emissions. A new methodology to evaluate those impacts in monetary terms has been designed and applied to Madrid. The method takes into account costs associated with losses in working time, mortality and human suffering; calculated using an impact pathway approach linked to CORINAIR emissions. This also allows the calculation of social costs associated with greenhouse gas impacts. As costs have been calculated individually by effect and mode of transport, they can be used to design pricing policies based on real social costs. This paper concludes that the health and social costs of transport-related air pollution in Madrid is 357 Meuro. In these circumstances, the recent public health tax applied in Madrid is clearly correct and sensible with a fair pricing policy on car use

  13. An assessment of hopanes in settled dust and air as indicators of exposure to traffic-related air pollution in Windsor, Ontario

    Science.gov (United States)

    Curran, Jason

    Traffic-related air pollution (TRAP) has been linked with several adverse health effects. We investigated hopanes, markers of primary particle emissions from gasoline and diesel engines, in house dust as an alternative approach for assessing exposure to TRAP in Windsor, Ontario. Settled house dust was collected from the homes of 28 study participants (10 -- 13 yrs). The dust was then analyzed for a suite of hopanes by gas chromatography-mass spectrometry. We calculated correlations between dust hopane concentrations and estimates of annual average NO2 concentrations derived from an existing LUR model. Hopanes were consistently present in detectable quantities in house dust. Annual average outdoor NO2 estimated was moderately correlated with hopanes in house dust (r = 0.46; pefficiency or the presence of an attached garage. Hopanes measured in settled house dust show promise as an indicator of long-term exposure to traffic-related air pollution. Keywords: hopane; air pollution; traffic; dust; exposure; TRAP.

  14. Development and deployment of AQUIS: A PC-based emission inventory calculator and air information management system

    Energy Technology Data Exchange (ETDEWEB)

    Smith, A.E.; Tschanz, J.; Monarch, M.; Narducci, P.; Bormet, S.

    1995-06-01

    The Air Quality Utility Information System (AQUIS) is a database management system. AQUIS assists users in calculation emissions, both traditional and toxic, and tracking and reporting emissions and source information. With some facilities having over 1200 sources and AQUIS calculating as many as 125 pollutants for a single source, tracking and correlating this information involve considerable effort. Originally designed for use at seven facilities of the Air Force Material Command, the user community has expanded to over 50 facilities since last reported at the 1993 Air and Waste Management Association (AWMA) annual meeting. This expansion in the user community has provided an opportunity to test the system under expanded operating conditions and in applications not anticipated during original system design. User feedback is used to determine needed enhancements and features and to prioritize the content of new releases. In responding to evolving user needs and new emission calculation procedures, it has been necessary to reconfigure AQUIS several times. Reconfigurations have ranged from simple to complex. These changes have necessitated augmenting quality assurance (QA) and validation procedures.

  15. The value of pulmonary vessel CT measuring and calculating of relative ratio

    International Nuclear Information System (INIS)

    Ji Jiansong; Xu Xiaoxiong; Lv Suzhen; Zhao Zhongwei; Wang Zufei; Xu Min; Gong Jianping

    2004-01-01

    Objective: To evaluate value of CT measurement and calculation of vessels of isolate pig lung, by compare with measurement and calculation of resin cast of them. Methods: CT scanned and measured the four isolated pig lung which vessels were full with ABS liquid or self-solidification resin liquid, and calculate the relative ratio of superior/inferior order and vein/artery of same order. After resin cast were made, measure and calculate the same as CT did. Results: Second order of calculation of vein/artery of same order by the two method had statistic difference (P 0.05). Conclusion: CT has high value in calculation of the relative ratio of superior/inferior order

  16. SU-E-T-552: Monte Carlo Calculation of Correction Factors for a Free-Air Ionization Chamber in Support of a National Air-Kerma Standard for Electronic Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Mille, M; Bergstrom, P [National Institute of Standards and Technology, Gaithersburg, MD (United States)

    2015-06-15

    Purpose: To use Monte Carlo radiation transport methods to calculate correction factors for a free-air ionization chamber in support of a national air-kerma standard for low-energy, miniature x-ray sources used for electronic brachytherapy (eBx). Methods: The NIST is establishing a calibration service for well-type ionization chambers used to characterize the strength of eBx sources prior to clinical use. The calibration approach involves establishing the well-chamber’s response to an eBx source whose air-kerma rate at a 50 cm distance is determined through a primary measurement performed using the Lamperti free-air ionization chamber. However, the free-air chamber measurements of charge or current can only be related to the reference air-kerma standard after applying several corrections, some of which are best determined via Monte Carlo simulation. To this end, a detailed geometric model of the Lamperti chamber was developed in the EGSnrc code based on the engineering drawings of the instrument. The egs-fac user code in EGSnrc was then used to calculate energy-dependent correction factors which account for missing or undesired ionization arising from effects such as: (1) attenuation and scatter of the x-rays in air; (2) primary electrons escaping the charge collection region; (3) lack of charged particle equilibrium; (4) atomic fluorescence and bremsstrahlung radiation. Results: Energy-dependent correction factors were calculated assuming a monoenergetic point source with the photon energy ranging from 2 keV to 60 keV in 2 keV increments. Sufficient photon histories were simulated so that the Monte Carlo statistical uncertainty of the correction factors was less than 0.01%. The correction factors for a specific eBx source will be determined by integrating these tabulated results over its measured x-ray spectrum. Conclusion: The correction factors calculated in this work are important for establishing a national standard for eBx which will help ensure that dose

  17. Analytic calculation of radio emission from parametrized extensive air showers : A tool to extract shower parameters

    NARCIS (Netherlands)

    Scholten, O.; Trinh, T. N. G.; de Vries, K. D.; Hare, B. M.

    2018-01-01

    The radio intensity and polarization footprint of a cosmic-ray induced extensive air shower is determined by the time-dependent structure of the current distribution residing in the plasma cloud at the shower front. In turn, the time dependence of the integrated charge-current distribution in the

  18. Spatial discretization methods for air gap permeance calculations in double salient traction motors

    NARCIS (Netherlands)

    Ilhan, E.; Kremers, M.F.J.; Motoasca, T.E.; Paulides, J.J.H.; Lomonova, E.

    2012-01-01

    Weight limitations in electric/hybrid cars demand the highest possible power-to-weight ratio from the traction motor, as in double salient permanent magnet (PM) machines. Their high flux densities in the air gap result in nonlinear analytical models, which need to be time optimized. The incorporated

  19. A numerical scheme to calculate temperature and salinity dependent air-water transfer velocities for any gas

    Science.gov (United States)

    Johnson, M. T.

    2010-02-01

    The transfer velocity determines the rate of exchange of a gas across the air-water interface for a given deviation from Henry's law equilibrium between the two phases. In the thin film model of gas exchange, which is commonly used for calculating gas exchange rates from measured concentrations of trace gases in the atmosphere and ocean/freshwaters, the overall transfer is controlled by diffusion-mediated films on either side of the air-water interface. Calculating the total transfer velocity (i.e. including the influence from both molecular layers) requires the Henry's law constant and the Schmidt number of the gas in question, the latter being the ratio of the viscosity of the medium and the molecular diffusivity of the gas in the medium. All of these properties are both temperature and (on the water side) salinity dependent and extensive calculation is required to estimate these properties where not otherwise available. The aim of this work is to standardize the application of the thin film approach to flux calculation from measured and modelled data, to improve comparability, and to provide a numerical framework into which future parameter improvements can be integrated. A detailed numerical scheme is presented for the calculation of the gas and liquid phase transfer velocities (ka and kw respectively) and the total transfer velocity, K. The scheme requires only basic physical chemistry data for any gas of interest and calculates K over the full range of temperatures, salinities and wind-speeds observed in and over the ocean. Improved relationships for the wind-speed dependence of ka and for the salinity-dependence of the gas solubility (Henry's law) are derived. Comparison with alternative schemes and methods for calculating air-sea flux parameters shows good agreement in general but significant improvements under certain conditions. The scheme is provided as a downloadable program in the supplementary material, along with input files containing molecular

  20. An inverse method for calculation of thermal inertia and heat gain in air conditioning and refrigeration systems

    International Nuclear Information System (INIS)

    Fayazbakhsh, M.A.; Bagheri, F.; Bahrami, M.

    2015-01-01

    Highlights: • An inverse method is proposed to calculate thermal inertia in HVAC-R systems. • Real-time thermal loads are estimated using the proposed intelligent algorithm. • Calculation algorithm is validated with on-site measurements. • Freezer duty cycle data are extracted only based on temperature measurements. - Abstract: A new inverse method is proposed for estimation of thermal inertia and heat gain in air conditioning and refrigeration systems using on-site temperature measurements. The method is applied on a walk-in freezer room of a restaurant in Surrey, British Columbia, Canada during one week of its regular operation. The thermal inertia and instantaneous heat gain are calculated and the results are validated using actual information of the materials inside the freezer room. The proposed method can be implemented in intelligent control systems designed for new and existing HVAC-R systems to improve their overall energy efficiency and reduce their environmental impacts

  1. Calculation of the dose rate and air ionisation from radioactive fallout deposited at Chilton, Oxon (1951 to 1977)

    International Nuclear Information System (INIS)

    Gibson, J.A.B.

    1978-06-01

    This report is a brief survey of the methods used for calculating the dose rate from deposited fallout and includes improvements in the computing techniques. The changes consist of (a) the use of a more exact allowance for weathering (b) the calculation doses to mid-month rather than end of each month (c) the inclusion of the contribution from Nb-95 in a more exact way to allow for its build-up and decay with time (d) the use of a more precise method for estimating the dose prior to 1954. The result is to increase the calculated total γ-ray dose from 1951 to 1976 by 17% from 153 to 179 mrad in air at 1 m with an increase of 11% in the beta-ray dose. The annual levels for natural γ and β radiation are 12 and 62 mrad respectively. (author)

  2. Investigation in order to precisely calculate the state of the air in dry underground mines

    Energy Technology Data Exchange (ETDEWEB)

    Aner, L; Krause, D; Schmidt, J

    1978-05-01

    A comparison between the calculation methods of Koenig, Batzel, Boldizsar, Mundry, Voss and Woropaew was made with data recorded in a test underground roadway over a period of one year. Precise measuring instruments were used, particularly for temperature measurement. The analysis and accompanying graphs show deviations in the results of the six calculation methods. A new mathematical formula is proposed, its parameters and a guide for application are given.

  3. A Python tool to set up relative free energy calculations in GROMACS.

    Science.gov (United States)

    Klimovich, Pavel V; Mobley, David L

    2015-11-01

    Free energy calculations based on molecular dynamics (MD) simulations have seen a tremendous growth in the last decade. However, it is still difficult and tedious to set them up in an automated manner, as the majority of the present-day MD simulation packages lack that functionality. Relative free energy calculations are a particular challenge for several reasons, including the problem of finding a common substructure and mapping the transformation to be applied. Here we present a tool, alchemical-setup.py, that automatically generates all the input files needed to perform relative solvation and binding free energy calculations with the MD package GROMACS. When combined with Lead Optimization Mapper (LOMAP; Liu et al. in J Comput Aided Mol Des 27(9):755-770, 2013), recently developed in our group, alchemical-setup.py allows fully automated setup of relative free energy calculations in GROMACS. Taking a graph of the planned calculations and a mapping, both computed by LOMAP, our tool generates the topology and coordinate files needed to perform relative free energy calculations for a given set of molecules, and provides a set of simulation input parameters. The tool was validated by performing relative hydration free energy calculations for a handful of molecules from the SAMPL4 challenge (Mobley et al. in J Comput Aided Mol Des 28(4):135-150, 2014). Good agreement with previously published results and the straightforward way in which free energy calculations can be conducted make alchemical-setup.py a promising tool for automated setup of relative solvation and binding free energy calculations.

  4. Assessment of exposure to traffic related air pollution of children attending schools near motorways

    International Nuclear Information System (INIS)

    Janssen, Nicole A.H.; Vliet, Patricia H.N. van; Aarts, Francee; Harssema, Hendrik; Brunekreef, Bert

    2001-01-01

    To assess exposure to air pollution from traffic of children attending schools near motorways, traffic related air pollution (PM 2.5 , NO 2 and benzene) was measured in and outside 24 schools located within 400m of motorways in the Netherlands. Reflectance of PM 2.5 filters was measured as a proxy for elemental carbon (EC). The relationship between this proxy and measurements of EC was studied in a sub-sample and a high correlation was established. In both indoor and outdoor air, concentrations of PM 2.5 and 'soot' significantly increased with increasing truck traffic density and significantly decreased with increasing distance. Indoor NO 2 concentrations significantly increased with increasing car traffic. The percentage of time that the school was downwind of the motorway during the measurements was significantly associated with 'soot' and NO 2 , but no with PM 2.5 and benzene. Estimated yearly averaged concentrations, calculated after standardising for differences in the background concentrations during the measurements, showed an about 2.5 fold range in 'soot', benzene (indoors and outdoors) and NO 2 (indoors) concentrations. For PM 2.5 (indoors and outdoors) and NO 2 outdoors the range was smaller (1.4-1.7). Standardised concentrations were highly correlated with the results of two other approaches that were used to order the exposures at the schools. This study has shown that concentrations of air pollutants in and outside schools near motorways are significantly associated with distance, traffic density and composition, and percentage of time downwind. These variables can therefore be used to assess exposure to traffic related air pollution of subjects living near motorways. Furthermore, the yearly averaged concentrations of PM 2.5 , soot, NO 2 and benzene can be used as a more direct measure of long-term exposure in epidemiological studies of the children attending the 24 schools. (Author)

  5. Analytical and numerical calculation of magnetic field distribution in the slotted air-gap of tangential surface permanent-magnet motors

    Directory of Open Access Journals (Sweden)

    Boughrara Kamel

    2009-01-01

    Full Text Available This paper deals with the analytical and numerical analysis of the flux density distribution in the slotted air gap of permanent magnet motors with surface mounted tangentially magnetized permanent magnets. Two methods for magnetostatic field calculations are developed. The first one is an analytical method in which the effect of stator slots is taken into account by modulating the magnetic field distribution by the complex relative air gap permeance. The second one is a numerical method using 2-D finite element analysis with consideration of Dirichlet and anti-periodicity (periodicity boundary conditions and Lagrange Multipliers for simulation of movement. The results obtained by the analytical method are compared to the results of finite-element analysis.

  6. Long-term effects of traffic-related air pollution on mortality in a Dutch cohort (NLCS-AIR study)

    NARCIS (Netherlands)

    Beelen, R.; Hoek, G.; Brandt, P.A. van den; Goldbohm, R.A.; Fischer, P.; Schouten, L.J.; Jerrett, M.; Hughes, E.; Armstrong, B.; Brunekreef, B.

    2008-01-01

    Background: Several studies have found an effect on mortality of between-city contrasts in long-term exposure to air pollution. The effect of within-city contrasts is still poorly understood. Objectives: We studied the association between long-term exposure to traffic-related air pollution and

  7. Calculation of the uncertainty associated to the result of entrance surface air kerma for conventional radiology patients

    International Nuclear Information System (INIS)

    Blanco, D.; Mora, P.; Khoury, H.; Fabri, D.; Leyton, F.; Cardenas, J.; Blanco, S.; Kodlulovich, S.; Roas, N.; Benavente, T.; Ortiz Lopez, P.; Ramirez, R.

    2008-01-01

    Radiation doses from diagnostic radiology are the largest contribution to the collective dose and the use of guidance (reference levels) has proven to be a tool for optimization of protection. Recently, with the support of the International Atomic Energy Agency (IAEA), eight countries of the Latin-American region have been working together on a programme to test methodologies for determining preliminary values of guidance levels for X-ray chest, lumbar spine and breast examinations. The approach used was to obtain entrance surface air kerma from measurements of X-ray tube outputs, corrected for distance and backscatter and later for real exposure parameters used with patients. For quality control, some of these values for a reduced number of patients were compared with direct TLD measurements directly placed on the patient during exposure. Given the number of parameters involved in the two methods, relatively large differences are deemed to be found in the comparison. The only way of deciding if measurements and calculations are outliers, for example, due to a systematic error or a mistake, is to compare these differences with the combined uncertainty. The aim of this paper is to present (in a detailed way) the methodology used in the pilot program ARCAL LXXV, the analyses of data performed within the survey and the estimated uncertainty. The parameters analyzed were: precision of the readings, positioning of the detector, reproducibility of the mAs and kV, long term stability of the instrument, radiation quality, kerma rate, radiation incidence, field size and field homogeneity, calibration factor of the equipment, temperature and pressure measurement, X-ray tube output curve adjustment, backscatter factor and focus-patient distance. The combined standard uncertainty for Ke in chest radiography in adult patients of standard complexion, was 12%, and the expanded uncertainty (k=2) was 24%. (author)

  8. Calculation of conversion coefficients using Chinese adult reference phantoms for air submersion and ground contamination.

    Science.gov (United States)

    Lu, Wei; Qiu, Rui; Wu, Zhen; Li, Chunyan; Yang, Bo; Liu, Huan; Ren, Li; Li, Junli

    2017-03-21

    The effective and organ equivalent dose coefficients have been widely used to provide assessment of doses received by adult members of the public and by workers exposed to environmental radiation from nuclear facilities under normal or accidental situations. Advancements in phantom types, weighting factors, decay data, etc, have led to the publication of newer results in this regard. This paper presents a new set of conversion coefficients for air submersion and ground contamination (with the use of Geant4) for photons from 15 keV to 10 MeV using the Chinese and International Commission on Radiological Protection (ICRP) adult reference male and female phantoms. The radiation fields, except for energy spectrum at low energies, were validated by the data obtained from the Monte Carlo code YURI. The effective dose coefficients of monoenergetic photons, obtained for the ICRP adult reference phantoms, agree well with recently published data for air submersion and ground contamination with a plane source at a depth of 0.5 g cm -2 in soil, but an average difference of 36.5% is observed for ground surface contamination with the abovementioned radiation field. The average differences in organ equivalent dose coefficients between the Chinese and the ICRP adult reference phantoms are within 6% for most organs, but noticeable differences of up to 70% or even higher are found at photon energies below 30 keV under air submersion. The effective dose coefficients obtained with the Chinese adult reference phantoms are greater than those of the ICRP adult reference phantoms above 30 keV and 0.5 MeV for ground contamination and air submersion, respectively; the average differences from the Chinese adult reference phantoms are about 3.6% and 0.4% in the whole energy range with maximum differences of 31.8% and 27.6% at 15 keV for air submersion and ground contamination respectively. These differences are attributed to anatomical discrepancies in overlying tissue mass of an

  9. The experimental viscosity and calculated relative viscosity of liquid In-Sn allcoys

    International Nuclear Information System (INIS)

    Wu, A.Q.; Guo, L.J.; Liu, C.S.; Jia, E.G.; Zhu, Z.G.

    2007-01-01

    The experimental measured viscosity of liquid pure Sn, In 20 Sn 80 and In 80 Sn 20 alloys was studied, and to make a comparison, the calculated relative viscosity based on the pair distribution functions, g(r), has also been studied. There is one peak in each experimental viscosity and calculated relative-viscosity curve of liquid pure Sn about 1000 deg. C. One valley appears in each experimental viscosity and calculated viscosity curve of liquid In 20 Sn 80 alloy about 700 deg. C. There is no abnormal behavior on In 80 Sn 20 alloy. The behavior of experimental viscosity and calculated relative viscosity is coincident with each other. Those results conformed that the temperature-induced structure anomalies reported before did take place

  10. Information needs related to teaching about air quality.

    Science.gov (United States)

    Cunningham, William P; Stubbs, Harriett S

    2003-06-01

    Translating knowledge of air quality into a form that can be understood by students and the general public is a major challenge for scientists, public officials, and teachers. Social science studies have shown that both educators and the general public are relatively uninformed about recent findings in environmental research. It is especially difficult to get students of today excited about environmental issues because environmental education has become institutionalized. Students believe they know about major environmental problems even when their knowledge is rudimentary or even wrong. One problem in getting public attention is the general level of hyperbole and hysteria common in most media. Thus, do we try to be even more shrill and apocalyptic than other advocates clamoring for public notice, or should we refuse to participate in this competition for attention?A model is presented to bring K-12 teachers, scientists, and students together to develop innovative, inquiry-based, active learning materials for environmental education. Curricular materials utilizing the discovery process can be created and tested in an iterative process that incorporates the results of current science research into highly effective teaching materials for schools. Following extensive evaluative procedures and review, exemplary materials are prepared for publication. This collaborative method also gives teachers and students a more realistic understanding of how science works by giving them access to active scientists and practical scientific experience.Finally, we argue that scientists need to reveal why they care about environmental issues. It is not enough to remain aloof and objective. If we are going to motivate students and the public to make changes in their lives, we need to make a convincing case for the importance of air quality and what it means in practical terms to our common environment.

  11. 76 FR 52731 - On-Line Complaint Form for Service-Related Issues in Air Transportation

    Science.gov (United States)

    2011-08-23

    ... for Service-Related Issues in Air Transportation AGENCY: Office of the Secretary, Department of... consumer protection and civil rights laws and regulations related to air transportation. The Enforcement... travelers, and to ensure safe and adequate service in air transportation. Filing a complaint using a web...

  12. Calculation of dose conversion factors for doses in the fingernails to organ doses at external gamma irradiation in air

    International Nuclear Information System (INIS)

    Khailov, A.M.; Ivannikov, A.I.; Skvortsov, V.G.; Stepanenko, V.F.; Orlenko, S.P.; Flood, A.B.; Williams, B.B.; Swartz, H.M.

    2015-01-01

    Absorbed doses to fingernails and organs were calculated for a set of homogenous external gamma-ray irradiation geometries in air. The doses were obtained by stochastic modeling of the ionizing particle transport (Monte Carlo method) for a mathematical human phantom with arms and hands placed loosely along the sides of the body. The resulting dose conversion factors for absorbed doses in fingernails can be used to assess the dose distribution and magnitude in practical dose reconstruction problems. For purposes of estimating dose in a large population exposed to radiation in order to triage people for treatment of acute radiation syndrome, the calculated data for a range of energies having a width of from 0.05 to 3.5 MeV were used to convert absorbed doses in fingernails to corresponding doses in organs and the whole body as well as the effective dose. Doses were assessed based on assumed rates of radioactive fallout at different time periods following a nuclear explosion. - Highlights: • Elemental composition and density of nails were determined. • MIRD-type mathematical human phantom with arms and hands was created. • Organ doses and doses to nails were calculated for external photon exposure in air. • Effective dose and nail doses values are close for rotational and soil surface exposures.

  13. Development of a method for calculating steady-state equipment sensible heat ratio of direct expansion air conditioning units

    International Nuclear Information System (INIS)

    Xia Liang; Chan, M.Y.; Deng Shiming

    2008-01-01

    A complete set of calculation method for steady-state equipment sensible heat ratio (SHR) for a direct expansion (DX) cooling coil has been developed and reported. The method was based on the fundamentals of energy conservation and heat and mass transfer taking place in the DX cooling coil, and was experimentally validated using an experimental DX A/C rig. With the method developed, the effect of refrigerant evaporating temperature at fixed inlet air conditions on equipment SHR has been theoretically analyzed. The validated method can be useful in further studying the inherent operating characteristics of a DX air conditioning (A/C) unit and in developing suitable control strategies for achieving higher energy efficiency and better indoor thermal environment

  14. Indoor and Outdoor Air Pollution- related Health Problem in Ethiopia: Review of Related Literature.

    Science.gov (United States)

    Tefera, Worku; Asfaw, Araya; Gilliland, Frank; Worku, Alemayehu; Wondimagegn, Mehari; Kumie, Abera; Samet, Jonathan; Berhane, Kiros

    2016-01-01

    The health effects of air pollution are generally global problems, but they have, since recently become issues of particular concern for developing countries. This review assessed the situation of air pollution and related health effects in the context of Ethiopia. The materials reviewed in this publication are published scientific papers from online search engines, unpublished government reports and academic theses/dissertations. In addition, interview data obtained from authorities and experts involved in the management of air quality were analyzed, interpreted and reported in the article. Review of the few studies conducted in Ethiopia showed that average concentrations of PM 2.5 reached as high as 280 µg/m 3 for 24-hour measurements (range: 2,417-12,739 µg/m 3 ). Indoor carbon monoxide (CO) levels were universally higher than regulatory limits for the United States and were found to be much higher among households using traditional stoves and solid biomass fuels. The use of traditional stoves and solid biomass fuels was reported in >95% of the households considered. High average levels of NO 2 (97 ppb) were reported in a large longitudinal study. The ambient PM 10 level was below the WHO guideline values in the majority of the samples. About 50% of the on-road CO samples taken from traffic roads in Addis Ababa were found to be less than the guideline values while the number of motor vehicles in Ethiopia is reported to be increasing by more than 9% per annum. There is a very limited air quality monitoring capacity in the country. The co-ordination between stakeholders in this regard is also inadequate. The limited evidence available on health effects of air pollution indicates that the prevalence of acute respiratory illness among children living in households using crude biomass fuels is significantly higher than the national average figures. The limited evidence reviewed and reported in this article indicates high levels of indoor air pollution and trends of

  15. 3-D heat transfer computer calculations of the performance of the IAEA's air-bath calorimeters

    International Nuclear Information System (INIS)

    Elias, E.; Kaizermann, S.; Perry, R.B.; Fiarman, S.

    1989-01-01

    A three dimensional (3-D) heat transfer computer code was developed to study and optimize the design parameters and to better understand the performance characteristics of the IAEA's air-bath calorimeters. The computer model accounts for heat conduction and radiation in the complex materials of the calorimeter and for heat convection and radiation at its outer surface. The temperature servo controller is modelled as an integral part of the heat balance equations in the system. The model predictions will be validated against test data using the ANL bulk calorimeter. 11 refs., 6 figs

  16. Potential impact of climate change on air pollution-related human health effects.

    Science.gov (United States)

    Tagaris, Efthimios; Liao, Kuo-Jen; Delucia, Anthony J; Deck, Leland; Amar, Praveen; Russell, Armistead G

    2009-07-01

    The potential health impact of ambient ozone and PM2.5 concentrations modulated by climate change over the United States is investigated using combined atmospheric and health modeling. Regional air quality modeling for 2001 and 2050 was conducted using CMAQ Modeling System with meteorology from the GISS Global Climate Model, downscaled regionally using MM5,keeping boundary conditions of air pollutants, emission sources, population, activity levels, and pollution controls constant. BenMap was employed to estimate the air pollution health outcomes at the county, state, and national level for 2050 caused by the effect of meteorology on future ozone and PM2.5 concentrations. The changes in calculated annual mean PM2.5 concentrations show a relatively modest change with positive and negative responses (increasing PM2.5 levels across the northeastern U.S.) although average ozone levels slightly decrease across the northern sections of the U.S., and increase across the southern tier. Results suggest that climate change driven air quality-related health effects will be adversely affected in more then 2/3 of the continental U.S. Changes in health effects induced by PM2.5 dominate compared to those caused by ozone. PM2.5-induced premature mortality is about 15 times higher then that due to ozone. Nationally the analysis suggests approximately 4000 additional annual premature deaths due to climate change impacts on PM2.5 vs 300 due to climate change-induced ozone changes. However, the impacts vary spatially. Increased premature mortality due to elevated ozone concentrations will be offset by lower mortality from reductions in PM2.5 in 11 states. Uncertainties related to different emissions projections used to simulate future climate, and the uncertainties forecasting the meteorology, are large although there are potentially important unaddressed uncertainties (e.g., downscaling, speciation, interaction, exposure, and concentration-response function of the human health studies).

  17. Cooling tower calculations

    International Nuclear Information System (INIS)

    Simonkova, J.

    1988-01-01

    The problems are summed up of the dynamic calculation of cooling towers with forced and natural air draft. The quantities and relations are given characterizing the simultaneous exchange of momentum, heat and mass in evaporative water cooling by atmospheric air in the packings of cooling towers. The method of solution is clarified in the calculation of evaporation criteria and thermal characteristics of countercurrent and cross current cooling systems. The procedure is demonstrated of the calculation of cooling towers, and correction curves and the effect assessed of the operating mode at constant air number or constant outlet air volume flow on their course in ventilator cooling towers. In cooling towers with the natural air draft the flow unevenness is assessed of water and air relative to its effect on the resulting cooling efficiency of the towers. The calculation is demonstrated of thermal and resistance response curves and cooling curves of hydraulically unevenly loaded towers owing to the water flow rate parameter graded radially by 20% along the cross-section of the packing. Flow rate unevenness of air due to wind impact on the outlet air flow from the tower significantly affects the temperatures of cooled water in natural air draft cooling towers of a design with lower demands on aerodynamics, as early as at wind velocity of 2 m.s -1 as was demonstrated on a concrete example. (author). 11 figs., 10 refs

  18. The Impact of Future Emissions Changes on Air Pollution Concentrations and Related Human Health Effects

    Science.gov (United States)

    Mikolajczyk, U.; Suppan, P.; Williams, M.

    2015-12-01

    Quantification of potential health benefits of reductions in air pollution on the local scale is becoming increasingly important. The aim of this study is to conduct health impact assessment (HIA) by utilizing regionally and spatially specific data in order to assess the influence of future emission scenarios on human health. In the first stage of this investigation, a modeling study was carried out using the Weather Research and Forecasting (WRF) model coupled with Chemistry to estimate ambient concentrations of air pollutants for the baseline year 2009, and for the future emission scenarios in southern Germany. Anthropogenic emissions for the baseline year 2009 are derived from the emission inventory provided by the Netherlands Organization of Applied Scientific Research (TNO) (Denier van der Gon et al., 2010). For Germany, the TNO emissions were replaced by gridded emission data with a high spatial resolution of 1/64 x 1/64 degrees. Future air quality simulations are carried out under different emission scenarios, which reflect possible energy and climate measures in year 2030. The model set-up included a nesting approach, where three domains with horizontal resolution of 18 km, 6 km and 2 km were defined. The simulation results for the baseline year 2009 are used to quantify present-day health burdens. Concentration-response functions (CRFs) for PM2.5 and NO2 from the WHO Health risks of air Pollution in Europe (HRAPIE) project were applied to population-weighted mean concentrations to estimate relative risks and hence to determine numbers of attributable deaths and associated life-years lost. In the next step, future health impacts of projected concentrations were calculated taking into account different emissions scenarios. The health benefits that we assume with air pollution reductions can be used to provide options for future policy decisions to protect public health.

  19. A conversion method of air-kerma from the primary, scatter and leakage radiations to ambient dose equivalent for calculating the mamography x-ray shielding barrier

    International Nuclear Information System (INIS)

    Kharrati, H.

    2005-01-01

    The primary, scatter, and leakage doses(in Gy), which constitute the data base for calculating shielding requirements for x-ray facilities, are often converted to the equivalent dose (in sievert) by using a constant of conversion of 1.145Sv/Gy. This constant is used for diagnostic radiology as well as for mammography spectra, and is derived by considering an exposure of 1 R corresponds to an air kerma of 8.73 m Gy, which renders by tradition an equivalent dose of 10 mSv. However, this conversion does not take into account the energy dependence of the conversion coefficients relating air kerma to the equivalent dose as described in ICRU report. Moreover, current radiation protection standards propose the use of the quantity ambient dose equivalent in order to qualify the efficiently of given radiation shielding. Therefore, in this study, a new approach has been introduced for derivation ambient dose equivalent from air kerma to calculate shielding requirements in mammography facilities. This new approach has been used to compute the conversion coefficients relating air kerma to ambient dose equivalent for mammography reference beam series of the Netherlands Metrology Institute Van Swinden Laboratorium (NMi), National Institute of Standards and Technology (NIST), and International Atomic Energy Agency (AIEA) laboratories. The calculation has been performed by the means of two methods which show a maximum deviation less than 10%2 for the primary, scatter, and leakage radiations. The results show that the conversion coefficients vary from 0.242 Sv/ Gy to 0.692 Sv/Gy with an average value of 0.436 Sv/Gy for the primary and the scatter radiations, and form 0.156 Sv/Gy to 1.329 Sv/Gy with an average value of 0.98 Sv/Gy for the leakage radiation. Simpkin et al. using an empirical approach propose a conversion value of 0.50 Sv/Gy for the mammography x-ray spectra. This value approximately coincides with the average conversion value of 0.436 Sv/Gy obtained in this work for

  20. Radiation dose distributions close to the shower axis calculated for high energy electron initiated electromagnetic showers in air

    International Nuclear Information System (INIS)

    Geer, S.; Gsponer, A.

    1983-01-01

    Absorbed radiation doses produced by 500, 1,000 and 10,000 MeV electron initiated electromagnetic showers in air have been calculated using a Monte Carlo program. The radial distributions of the absorbed dose near to the shower axis are found to be significantly narrower than predicted by simple analytical shower theory. For a 500 MeV, 10 kA, 100 ns electron beam pulse, the region in which the total dose is in excess of 1 krad and the dose rate in excess of 10 10 rad/s is a cigar-shaped envelope of radius 1 m and length 200 m. (orig.) [de

  1. A law of removing radon by ventilation and air requirement calculation for eliminating radon daughters in uranium mines

    International Nuclear Information System (INIS)

    Wu Gang

    1988-06-01

    In accordance with testing data of removing radon and its daughters by ventilation from shrinkage and filling stopes of uranium mines, a law of removing radon by ventilation from the stopes is analyzed and summed. According to the decay law of radon and its daughters, an accumulation equation of potential alpha energy from radon daughters is presented with hyperbolic regression equation. the calculating formulae of ventilation flow are derived from the accumulation equation for eliminating radon daughters in inlet flow with or without contamination. It has been proved that the amount of ventilation air calcuated could meet the requirements of radiation safety rationally and economically

  2. NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS (NESHAP) SUBPART H RADIONUCLIDES POTENTIAL TO EMIT CALCULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    EARLEY JN

    2008-07-23

    This document provides an update of the status of stacks on the Hanford Site and the potential radionuclide emissions, i.e., emissions that could occur with no control devices in place. This review shows the calculations that determined whether the total effective dose equivalent (TEDE) received by the maximum public receptor as a result of potential emissions from any one of these stacks would exceed 0.1 millirem/year. Such stacks require continuous monitoring of the effluent, or other monitoring, to meet the requirements of Washington Administrative code (WAC) 246-247-035(1)(a)(ii) and WAC 246-247-075(1), -(2), and -(6). This revised update reviews the potential-to-emit (PTE) calculations of 31 stacks for Fluor Hanford, Inc. Of those 31 stacks, 11 have the potential to cause a TEDE greater than 0.1 mrem/year.

  3. NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS (NESHAP) SUBPART H; RADIONUCLIDES POTENTIAL-TO-EMIT CALCULATIONS

    International Nuclear Information System (INIS)

    EARLEY JN

    2008-01-01

    This document provides an update of the status of stacks on the Hanford Site and the potential radionuclide emissions, i.e., emissions that could occur with no control devices in place. This review shows the calculations that determined whether the total effective dose equivalent (TEDE) received by the maximum public receptor as a result of potential emissions from any one of these stacks would exceed 0.1 millirem/year. Such stacks require continuous monitoring of the effluent, or other monitoring, to meet the requirements of Washington Administrative code (WAC) 246-247-035(1)(a)(ii) and WAC 246-247-075(1), -(2), and -(6). This revised update reviews the potential-to-emit (PTE) calculations of 31 stacks for Fluor Hanford, Inc. Of those 31 stacks, 11 have the potential to cause a TEDE greater than 0.1 mrem/year

  4. Improved Accuracy of Density Functional Theory Calculations for CO2 Reduction and Metal-Air Batteries

    DEFF Research Database (Denmark)

    Christensen, Rune; Hansen, Heine Anton; Vegge, Tejs

    2015-01-01

    Density functional theory (DFT) calculations have greatly contributed to the atomic level understanding of electrochemical reactions. However, in some cases, the accuracy can be prohibitively low for a detailed understanding of, e.g. reaction mechanisms. Two cases are examined here, i.e. the elec......Density functional theory (DFT) calculations have greatly contributed to the atomic level understanding of electrochemical reactions. However, in some cases, the accuracy can be prohibitively low for a detailed understanding of, e.g. reaction mechanisms. Two cases are examined here, i.......47 eV and 0.17 eV using metals as reference. The presented approach for error identification is expected to be applicable to a very broad range of systems. References: [1] A. A. Peterson, F. Abild-Pedersen, F. Studt, J. Rossmeisl, and J. K. Nørskov, Energy Environ. Sci., 3,1311 (2010) [2] F. Studt, F...

  5. Modeling personal exposure to traffic related air pollutants

    NARCIS (Netherlands)

    Montagne, D.R.

    2015-01-01

    The first part of this thesis is about the VE3SPA project. Land use regression (LUR) models are often used to predict the outdoor air pollution at the home address of study participants, to study long-term effects of air pollution. While several studies have documented that PM2.5 mass measured at a

  6. Energy Payback Time Calculation for a Building Integrated Semitransparent Thermal (BISPVT) System with Air Duct

    OpenAIRE

    Kanchan Mudgil; Deepali Kamthania

    2013-01-01

    This paper evaluates the energy payback time (EPBT) of building integrated photovoltaic thermal (BISPVT) system for Srinagar, India. Three different photovoltaic (PV) modules namely mono crystalline silicon (m-Si), poly crystalline silicon (p-Si), and amorphous silicon (a-Si) have been considered for calculation of EPBT. It is found that, the EPBT is lowest in m-Si. Hence, integration of m-Si PV modules on the roof of a room is economical.

  7. Exploring PHD fingers and H3K4me0 interactions with molecular dynamics simulations and binding free energy calculations: AIRE-PHD1, a comparative study.

    Directory of Open Access Journals (Sweden)

    Dimitrios Spiliotopoulos

    Full Text Available PHD fingers represent one of the largest families of epigenetic readers capable of decoding post-translationally modified or unmodified histone H3 tails. Because of their direct involvement in human pathologies they are increasingly considered as a potential therapeutic target. Several PHD/histone-peptide structures have been determined, however relatively little information is available on their dynamics. Studies aiming to characterize the dynamic and energetic determinants driving histone peptide recognition by epigenetic readers would strongly benefit from computational studies. Herein we focus on the dynamic and energetic characterization of the PHD finger subclass specialized in the recognition of histone H3 peptides unmodified in position K4 (H3K4me0. As a case study we focused on the first PHD finger of autoimmune regulator protein (AIRE-PHD1 in complex with H3K4me0. PCA analysis of the covariance matrix of free AIRE-PHD1 highlights the presence of a "flapping" movement, which is blocked in an open conformation upon binding to H3K4me0. Moreover, binding free energy calculations obtained through Molecular Mechanics/Poisson-Boltzmann Surface Area (MM/PBSA methodology are in good qualitative agreement with experiments and allow dissection of the energetic terms associated with native and alanine mutants of AIRE-PHD1/H3K4me0 complexes. MM/PBSA calculations have also been applied to the energetic analysis of other PHD fingers recognizing H3K4me0. In this case we observe excellent correlation between computed and experimental binding free energies. Overall calculations show that H3K4me0 recognition by PHD fingers relies on compensation of the electrostatic and polar solvation energy terms and is stabilized by non-polar interactions.

  8. Science Shop and NGO activities related to air pollution

    DEFF Research Database (Denmark)

    Jørgensen, Michael Søgaard; Brodersen, Søsser

    2005-01-01

    The paper describes activities, which these organisations and science shops carry out within the field of air pollution and its analysis, abatement and prevention. The activities have been mapped and analysed through dialogue with a number of these organisations. The activities include activities...... with focus on development of citizens' capacity for measurement and assessment of air pollution and strategies for abatement and prevention of air pollution. The paper discusses also possibilities for further development of dialogue and co-operation between civil society, science shops and ACCENT researchers....

  9. Standing steady-state wave-making calculation method for air cushion vehicles; Air cushion vehicle no teijo zoha keisanho ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, T [Mitsui Engineering and Shipbuilding Co. Ltd., Tokyo (Japan)

    1996-04-10

    The pulse-height distribution of a cushion room of air cushion vehicle (ACV) has been tried to be approached by means of the panel shift type Rankine source method. When using this method, it was not required to introduce the pressure distribution model simulating the fall-off effect for the step-formed cushion pressure distribution. The wave form and wave making resistance could be estimated precisely by assigning the pressure gradient to one longitudinal direction panel in the calculation. The waveform shape within the cushion room could be calculated rather precisely by comparing with the analytic solution. This calculation method did have an ability providing the pulse-height information in the cushion room of ACV for seal design and configuration of ships. The analytic solution using for the comparison was sufficient for determining the pulse-height in the high speed region. However, it was hard to respond to non-linear problems or optional shape problems. It was pointed out to be further improved. 5 refs., 8 figs.

  10. European transboundary acidifying air pollution. Ten years calculated fields and budgets to the end of the first Sulphur Protocol

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, K.; Seland, Oe.; Foss, A.; Mylona, S.; Sandnes, H.; Styve, H.; Tarrason, L.

    1995-07-01

    The Cooperative Programme for the Monitoring and Evaluation of the Long Range Transmission and Air Pollutants in Europe, EMEP, plays an integral part in data collection and scientific cooperation for implementation of the 1979 Geneva Convention on Long Range Transboundary Air Pollution. Within EMEP, the Meteorological Synthesizing Centre - West (MSC-W) is an international technical centre. The purpose of the MSC-W, focusing in part on acidifying substances, is to estimate the concentrations of relevant sulphur and nitrogen pollutants across Europe on the basis of emission information and meteorological data, and to estimate the transboundary fluxes of these substances. Responding to these specific obligations, the report presents calculations of sulphur and nitrogen concentrations and depositions and of their transboundary fluxes. The calculations are performed by the receptor oriented one layer trajectory (Lagrangian) acid deposition model, which during 1995 has been used to estimate acidifying pollutant fluxes for the ten year period 1985-1994. This corresponds to the period between initial signing and conclusion of the first Sulphur Protocol, signed in Helsinki in 1985. 90 refs., 42 figs., 43 tabs.

  11. Preliminary Calculations of Bypass Flow Distribution in a Multi-Block Air Test

    International Nuclear Information System (INIS)

    Kim, Min Hwan; Tak, Nam Il

    2011-01-01

    The development of a methodology for the bypass flow assessment in a prismatic VHTR (Very High Temperature Reactor) core has been conducted at KAERI. A preliminary estimation of variation of local bypass flow gap size between graphite blocks in the NHDD core were carried out. With the predicted gap sizes, their influence on the bypass flow distribution and the core hot spot was assessed. Due to the complexity of gap distributions, a system thermo-fluid analysis code is suggested as a tool for the core thermo-fluid analysis, the model and correlations of which should be validated. In order to generate data for validating the bypass flow analysis model, an experimental facility for a multi-block air test was constructed at Seoul National University (SNU). This study is focused on the preliminary evaluation of flow distribution in the test section to understand how the flow is distributed and to help the selection of experimental case. A commercial CFD code, ANSYS CFX is used for the analyses

  12. Human perception, productivity and symptoms related to indoor air quality

    Energy Technology Data Exchange (ETDEWEB)

    Wargocki, P

    1998-08-01

    Three objectives of the present study are formulated: (1) to investigate whether total sensory pollution load on the air in space can be estimated by adding sensory pollution loads from the individual pollution sources; (2) to develop alternative reference exposures which can be used to calibrate sensory evaluations of the air quality indoors made by trained subjects; and (3) to investigate whether decreasing the pollution loads on the air indoors is an effective measure for improving the perceived air quality, reducing the prevalence of health symptoms and increasing people`s productivity. Limited data exist on the addition of families of sensory pollution, sources, i.e., building materials, people and tobacco smoke (research was mainly performed on building materials), and that no field study on addition has been carried out previously. Consequently, laboratory and field experiments on the addition of families of sensory pollution sources were undertaken. Reducing the sensory pollution load on the air indoors proved to be an effective and energy-efficient measure to improve the perceived quality of air, to lower the prevalence of symptoms and to improve productivity. Suggestions for future experiments are made including, i.a., using other sub-populations of subjects stratified for age, sensitivity and type of work, other pollution sources, as well as the independent measures design and repeated exposures to the same environmental conditions. (EG) 209 refs.

  13. A numerical scheme to calculate temperature and salinity dependent air-water transfer velocities for any gas

    Directory of Open Access Journals (Sweden)

    M. T. Johnson

    2010-10-01

    Full Text Available The ocean-atmosphere flux of a gas can be calculated from its measured or estimated concentration gradient across the air-sea interface and the transfer velocity (a term representing the conductivity of the layers either side of the interface with respect to the gas of interest. Traditionally the transfer velocity has been estimated from empirical relationships with wind speed, and then scaled by the Schmidt number of the gas being transferred. Complex, physically based models of transfer velocity (based on more physical forcings than wind speed alone, such as the NOAA COARE algorithm, have more recently been applied to well-studied gases such as carbon dioxide and DMS (although many studies still use the simpler approach for these gases, but there is a lack of validation of such schemes for other, more poorly studied gases. The aim of this paper is to provide a flexible numerical scheme which will allow the estimation of transfer velocity for any gas as a function of wind speed, temperature and salinity, given data on the solubility and liquid molar volume of the particular gas. New and existing parameterizations (including a novel empirical parameterization of the salinity-dependence of Henry's law solubility are brought together into a scheme implemented as a modular, extensible program in the R computing environment which is available in the supplementary online material accompanying this paper; along with input files containing solubility and structural data for ~90 gases of general interest, enabling the calculation of their total transfer velocities and component parameters. Comparison of the scheme presented here with alternative schemes and methods for calculating air-sea flux parameters shows good agreement in general. It is intended that the various components of this numerical scheme should be applied only in the absence of experimental data providing robust values for parameters for a particular gas of interest.

  14. A numerical scheme to calculate temperature and salinity dependent air-water transfer velocities for any gas

    Science.gov (United States)

    Johnson, M. T.

    2010-10-01

    The ocean-atmosphere flux of a gas can be calculated from its measured or estimated concentration gradient across the air-sea interface and the transfer velocity (a term representing the conductivity of the layers either side of the interface with respect to the gas of interest). Traditionally the transfer velocity has been estimated from empirical relationships with wind speed, and then scaled by the Schmidt number of the gas being transferred. Complex, physically based models of transfer velocity (based on more physical forcings than wind speed alone), such as the NOAA COARE algorithm, have more recently been applied to well-studied gases such as carbon dioxide and DMS (although many studies still use the simpler approach for these gases), but there is a lack of validation of such schemes for other, more poorly studied gases. The aim of this paper is to provide a flexible numerical scheme which will allow the estimation of transfer velocity for any gas as a function of wind speed, temperature and salinity, given data on the solubility and liquid molar volume of the particular gas. New and existing parameterizations (including a novel empirical parameterization of the salinity-dependence of Henry's law solubility) are brought together into a scheme implemented as a modular, extensible program in the R computing environment which is available in the supplementary online material accompanying this paper; along with input files containing solubility and structural data for ~90 gases of general interest, enabling the calculation of their total transfer velocities and component parameters. Comparison of the scheme presented here with alternative schemes and methods for calculating air-sea flux parameters shows good agreement in general. It is intended that the various components of this numerical scheme should be applied only in the absence of experimental data providing robust values for parameters for a particular gas of interest.

  15. Model equations for Calculating Rn-gas Concentrations in Air of Uranium Exploratory Tunnels, Allouga, West-Central Sinai , Egypt

    International Nuclear Information System (INIS)

    Abdel-Monem, A.A.; Soliman, S.F.H.; Abd El-Kader, F.H.; El-Naggar, A.M.; Eissa, H.M.; Abd El-Hafez, A.A.

    2001-01-01

    Gabal Allouga area is located some 40 km due east from Abu Zenima town on the east coast of the Gulf of Suez, West-Central Sinai, Egypt. A network of exploratory tunnels totaling 670m in length and approximately 2x2 m in cross section, were excavated within a paleosol clayey bed. They host (Fe, Mn)-, Cu-, and U-mineralizations. Portions of the tunnels are naturally ventilated and others portions are non-ventilated and show ground water seepage through fractures. Model equations were developed for calculating the Rn-gas concentrations in the air of the tunnels under dry conditions where Rn-gas transport is mainly by air flow through porous media as well as for wet conditions where Rn-gas transport is mainly by ground water flow into the tunnels. Under dry conditions the model calculated Rn-gas concentrations(15.2-60.6 PCi/1) are consistent with measured values by active techniques (3.26-22.85 pCi/1) and by SSNTD techniques (19-69.1 pCi/1) when the Rn-emanation coefficient (alpha= 0.05-0.2), the emanating rock thickness (X=10 cm) and U-concentration averages 30 ppm. Under wet and non-ventilated conditions the model calculated Rn-gas concentrations (159-1248 pCi/1) are consistent with the measured values by active techniques (231-1348 pCi/1) and by SSNTD techniques (144-999pCi/1), when the Rn-emanation coefficient (alpha=0.1-0.25), the ground water flow (F=0.04-0.10 ml/s -1 cm -2 ) and U-concertrations (100-250ppm)

  16. Method for calculating steady-state waves in an air cushion vehicle. Part 2; Air cushion vehicle no teijo zoha keisanho ni tsuite. 2

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, T [Mitsui Engineering and Shipbuilding Co. Ltd., Tokyo (Japan)

    1997-10-01

    Discussions were given on a method to estimate resistance constituents in wave resistance made in an air chamber of an air cushion vehicle (ACV). An orthogonal coordinate system is considered, which uses the center of a hull as the zero point and is made dimensionless by using cushion length. Flow around the ACV is supposed as an ideal flow, whereas speed potential is defined in the flow field. Then, a linear free surface condition is hypothesized on water surface Z = 0. Number and density of waves were used to introduce a condition to be satisfied by the speed potential. A numerical calculation method arranged a blow-out panel on the water surface, and used a panel shift type Rankine source method which satisfies the free surface condition at Z = 0. Cushion pressure distribution becomes a step-like discontinuous function, and mathematical infinity is generated in the differentiation values. Under an assumption that the pressure rises per one panel where pressure jump is present, the distribution was approximated by providing one panel with inclination of the finite quantity therein. Estimation on wave height distribution in the cushion chamber showed a tendency of qualitatively agreeing with the experimental result, but the wave heights shown in the experiment had the average level decreased as it goes toward the rear of the hull. 5 refs., 5 figs.

  17. Accuracy requirements for the calculation of gravitational waveforms from coalescing compact binaries in numerical relativity

    International Nuclear Information System (INIS)

    Miller, Mark

    2005-01-01

    I discuss the accuracy requirements on numerical relativity calculations of inspiraling compact object binaries whose extracted gravitational waveforms are to be used as templates for matched filtering signal extraction and physical parameter estimation in modern interferometric gravitational wave detectors. Using a post-Newtonian point particle model for the premerger phase of the binary inspiral, I calculate the maximum allowable errors for the mass and relative velocity and positions of the binary during numerical simulations of the binary inspiral. These maximum allowable errors are compared to the errors of state-of-the-art numerical simulations of multiple-orbit binary neutron star calculations in full general relativity, and are found to be smaller by several orders of magnitude. A post-Newtonian model for the error of these numerical simulations suggests that adaptive mesh refinement coupled with second-order accurate finite difference codes will not be able to robustly obtain the accuracy required for reliable gravitational wave extraction on Terabyte-scale computers. I conclude that higher-order methods (higher-order finite difference methods and/or spectral methods) combined with adaptive mesh refinement and/or multipatch technology will be needed for robustly accurate gravitational wave extraction from numerical relativity calculations of binary coalescence scenarios

  18. Changes in ocular and nasal signs and symptoms among air crew in relation to air humidification on intercontinental flights.

    Science.gov (United States)

    Norbäck, Dan; Lindgren, Torsten; Wieslander, Gunilla

    2006-04-01

    This study evaluates the influence of air humidification in aircraft on symptoms, tear-film stability, nasal patency, and peak expiratory flow. Commercial air crew (N=71) were given a medical examination during eight flights from Stockholm to Chicago and eight flights in the opposite direction. Examinations were done onboard one Boeing 767 aircraft equipped with an evaporation humidifier in the forward part of the cabin. The investigators followed the air crew, staying one night in Chicago and returning with the same crew. Four of the flights had the air humidification device active in-flight to Chicago and deactivated when returning to Stockholm. The other four flights had the inverse humidification sequence. The humidification sequence was randomized and double blind. Hygienic measurements were performed. The humidification increased the relative air humidity by 10% in the 1st row in business class, by 3% in the last row (39th row) in tourist class, and by 3% in the cockpit. Air humidification increased tear-film stability and nasal patency and decreased ocular, nasal, and dermal symptoms and headache. The mean concentration of viable bacteria [77-108 colony-forming units (cfu)/m(3)], viable molds (74-84 cfu/m(3)), and particulate matter (1-8 microg/m(3)) was low, both during the humidified and non-humidified flights. Relative air humidity is low (10-12%) during intercontinental flights and can be increased by the use of a ceramic evaporation humidifier, without any measurable increase of microorganisms in cabin air. Air humidification could increase passenger and crew comfort by increasing tear-film stability and nasal patency and reducing various symptoms.

  19. Air pollution in Thailand using nuclear-related analytical techniques

    International Nuclear Information System (INIS)

    Leelhaphunt, N.; Chueinta, W.

    1994-01-01

    The methods of neutron activation, both instrumental and radiochemical, and atomic absorption spectrophotometry are used in a study of the concentrations of Al, As, Br, Cd, Cl, Co, Cr, Cu, Fe, Hg, Mn, Sb, Sc, Se, Si, V, Zn and Pb in airborne particulate matter collected from 7 permanent and 9 temporary air quality monitoring stations. The location of the stations are urban residential, suburban residential, mixed (commercial and residential), commercial and industrial areas and near major roads in Bangkok Metropolitan areas. Air sampling is performed once a month for 24 hours continuously using the high volume air sampler (GMW 2000 H) and for 5, 10, and 15 days continuously using an Anderson Air Sampler (SIBATA AN-200). The elements As, Cd and Cu are determined destructively using ion exchange chromatography while Hg and Se are determined by the dry combustion technique. The determination of Pb was done by atomic absorption spectrophotometry. The results of Pb concentrations in airborne particulate matters, collected during 1987 to 1991, were reported by the Office of the National Environment Board. Levels of Pb content were found to be lower than the National Ambient Air Quality Standards. (author). 3 refs, 4 tabs

  20. Calculation of the Arc Velocity Along the Polluted Surface of Short Glass Plates Considering the Air Effect

    Directory of Open Access Journals (Sweden)

    Tao Yuan

    2012-03-01

    Full Text Available To investigate the microphysics mechanism and the factors that influence arc development along a polluted surface, the arc was considered as a plasma fluid. Based on the image method and the collision ionization theory, the electric field of the arc needed to maintain movement with different degrees of pollution was calculated. According to the force of the charged particle in an arc plasma stressed under an electric field, a calculation model of arc velocity, which is dependent on the electric field of the arc head that incorporated the effects of airflow around the electrode and air resistance is presented. An experiment was carried out to measure the arc velocity, which was then compared with the calculated value. The results of the experiment indicated that the lighter the pollution is, the larger the electric field of the arc head and arc velocity is; when the pollution is heavy, the effect of thermal buoyancy that hinders arc movement increases, which greatly reduces the arc velocity.

  1. SU-E-T-800: Verification of Acurose XB Dose Calculation Algorithm at Air Cavity-Tissue Interface Using Film Measurement for Small Fields of 6-MV Flattening Filter-Free Beams

    International Nuclear Information System (INIS)

    Kang, S; Suh, T; Chung, J

    2015-01-01

    Purpose: To verify the dose accuracy of Acuros XB (AXB) dose calculation algorithm at air-tissue interface using inhomogeneous phantom for 6-MV flattening filter-free (FFF) beams. Methods: An inhomogeneous phantom included air cavity was manufactured for verifying dose accuracy at the air-tissue interface. The phantom was composed with 1 and 3 cm thickness of air cavity. To evaluate the central axis doses (CAD) and dose profiles of the interface, the dose calculations were performed for 3 × 3 and 4 × 4 cm 2 fields of 6 MV FFF beams with AAA and AXB in Eclipse treatment plainning system. Measurements in this region were performed with Gafchromic film. The root mean square errors (RMSE) were analyzed with calculated and measured dose profile. Dose profiles were divided into inner-dose profile (>80%) and penumbra (20% to 80%) region for evaluating RMSE. To quantify the distribution difference, gamma evaluation was used and determined the agreement with 3%/3mm criteria. Results: The percentage differences (%Diffs) between measured and calculated CAD in the interface, AXB shows more agreement than AAA. The %Diffs were increased with increasing the thickness of air cavity size and it is similar for both algorithms. In RMSEs of inner-profile, AXB was more accurate than AAA. The difference was up to 6 times due to overestimation by AAA. RMSEs of penumbra appeared to high difference for increasing the measurement depth. Gamma agreement also presented that the passing rates decreased in penumbra. Conclusion: This study demonstrated that the dose calculation with AXB shows more accurate than with AAA for the air-tissue interface. The 2D dose distributions with AXB for both inner-profile and penumbra showed better agreement than with AAA relative to variation of the measurement depths and air cavity sizes

  2. Inflammatory markers in relation to long-term air pollution

    NARCIS (Netherlands)

    Mostafavi Montazeri, Nahid|info:eu-repo/dai/nl/375290575; Vlaanderen, Jelle|info:eu-repo/dai/nl/31403160X; Chadeau-Hyam, Marc; Beelen, Rob|info:eu-repo/dai/nl/30483100X; Modig, Lars; Palli, Domenico; Bergdahl, Ingvar A; Vineis, Paolo; Hoek, Gerard|info:eu-repo/dai/nl/069553475; Kyrtopoulos, Soterios Α; Vermeulen, Roel|info:eu-repo/dai/nl/216532620

    Long-term exposure to ambient air pollution can lead to chronic health effects such as cancer, cardiovascular and respiratory disease. Systemic inflammation has been hypothesized as a putative biological mechanism contributing to these adverse health effects. We evaluated the effect of long-term

  3. Future directions of meteorology related to air-quality research.

    Science.gov (United States)

    Seaman, Nelson L

    2003-06-01

    Meteorology is one of the major factors contributing to air-pollution episodes. More accurate representation of meteorological fields has been possible in recent years through the use of remote sensing systems, high-speed computers and fine-mesh meteorological models. Over the next 5-20 years, better meteorological inputs for air quality studies will depend on making better use of a wealth of new remotely sensed observations in more advanced data assimilation systems. However, for fine mesh models to be successful, parameterizations used to represent physical processes must be redesigned to be more precise and better adapted for the scales at which they will be applied. Candidates for significant overhaul include schemes to represent turbulence, deep convection, shallow clouds, and land-surface processes. Improvements in the meteorological observing systems, data assimilation and modeling, coupled with advancements in air-chemistry modeling, will soon lead to operational forecasting of air quality in the US. Predictive capabilities can be expected to grow rapidly over the next decade. This will open the way for a number of valuable new services and strategies, including better warnings of unhealthy atmospheric conditions, event-dependent emissions restrictions, and now casting support for homeland security in the event of toxic releases into the atmosphere.

  4. Traffic-related air pollution and otitis media

    NARCIS (Netherlands)

    Brauer, Michael; Gehring, Ulrike; Brunekreef, Bert; de Jongste, Johan; Gerritsen, Jorrit; Rovers, Maroeska; Wichmann, Heinz-Erich; Wijga, Alet; Heinrich, Joachim

    BACKGROUND: Otitis media is one of the most common infections in young children. Although exposure to environmental tobacco smoke is a known risk factor associated with otitis media, little information is available regarding the potential association with air pollution. OBJECTIVE: We set out to

  5. Relative Dating and Classification of Minerals and Rocks Based on Statistical Calculations Related to Their Potential Energy Index

    OpenAIRE

    Labushev, Mikhail M.; Khokhlov, Alexander N.

    2012-01-01

    Index of proportionality of atomic weights of chemical elements is proposed for determining the relative age of minerals and rocks. Their chemical analysis results serve to be initial data for calculations. For rocks of different composition the index is considered to be classification value as well. Crystal lattice energy change in minerals and their associations can be measured by the index value change, thus contributing to the solution of important practical problems. There was determined...

  6. Relative Motion of the WDS 05110+3203 STF 648 System, With a Protocol for Calculating Relative Motion

    Science.gov (United States)

    Wiley, E. O.

    2010-07-01

    Relative motion studies of visual double stars can be investigated using least squares regression techniques and readily accessible programs such as Microsoft Excel and a calculator. Optical pairs differ from physical pairs under most geometries in both their simple scatter plots and their regression models. A step-by-step protocol for estimating the rectilinear elements of an optical pair is presented. The characteristics of physical pairs using these techniques are discussed.

  7. A real-time monitoring and assessment method for calculation of total amounts of indoor air pollutants emitted in subway stations.

    Science.gov (United States)

    Oh, TaeSeok; Kim, MinJeong; Lim, JungJin; Kang, OnYu; Shetty, K Vidya; SankaraRao, B; Yoo, ChangKyoo; Park, Jae Hyung; Kim, Jeong Tai

    2012-05-01

    Subway systems are considered as main public transportation facility in developed countries. Time spent by people in indoors, such as underground spaces, subway stations, and indoor buildings, has gradually increased in the recent past. Especially, operators or old persons who stay in indoor environments more than 15 hr per day usually influenced a greater extent by indoor air pollutants. Hence, regulations on indoor air pollutants are needed to ensure good health of people. Therefore, in this study, a new cumulative calculation method for the estimation of total amounts of indoor air pollutants emitted inside the subway station is proposed by taking cumulative amounts of indoor air pollutants based on integration concept. Minimum concentration of individual air pollutants which naturally exist in indoor space is referred as base concentration of air pollutants and can be found from the data collected. After subtracting the value of base concentration from data point of each data set of indoor air pollutant, the primary quantity of emitted air pollutant is calculated. After integration is carried out with these values, adding the base concentration to the integration quantity gives the total amount of indoor air pollutant emitted. Moreover the values of new index for cumulative indoor air quality obtained for 1 day are calculated using the values of cumulative air quality index (CAI). Cumulative comprehensive indoor air quality index (CCIAI) is also proposed to compare the values of cumulative concentrations of indoor air pollutants. From the results, it is clear that the cumulative assessment approach of indoor air quality (IAQ) is useful for monitoring the values of total amounts of indoor air pollutants emitted, in case of exposure to indoor air pollutants for a long time. Also, the values of CCIAI are influenced more by the values of concentration of NO2, which is released due to the use of air conditioners and combustion of the fuel. The results obtained in

  8. Calculation of neutron and gamma-ray energy spectra in liquid air and liquid nitrogen due to 14-MeV neutron and californium-252 sources

    International Nuclear Information System (INIS)

    Straker, E.A.; Gritzner, M.L.; Harris, L. Jr.

    1978-01-01

    Calculations of neutron and gamma-ray fluences from 14-MeV neutron and 252 Cf sources in liquid air and liquid nitrogen have been performed. These calculations were made specifically for comparison with experimental data measured at Stohl, Federal Republic of Germany. The discrete-ordinates method was utilized with neutron and gamma-ray cross sections from ENDF/B-IV. One-dimensional calculational models were developed for the sources and tank. Limited comparisons are made with experimental data

  9. Measures related to traffic planning for air pollution control

    Energy Technology Data Exchange (ETDEWEB)

    Baumueller, J; Reuter, U [Office of Environmental Protection, Stuttgart (Germany). Dept. for Climatology

    1996-12-31

    The immense increase of motor traffic, in the future reinforced by the European market and the opening of boarders to the east countries, requires new efforts in traffic policy. In the city agglomerations the motor traffic is nearly collapsing. The increase of motor traffic is the reason for a considerable degradation of environment, especially by noise and air pollution. For the region of Stuttgart the problems and possibilities of counter-measures are discussed. (author)

  10. Measures related to traffic planning for air pollution control

    Energy Technology Data Exchange (ETDEWEB)

    Baumueller, J.; Reuter, U. [Office of Environmental Protection, Stuttgart (Germany). Dept. for Climatology

    1995-12-31

    The immense increase of motor traffic, in the future reinforced by the European market and the opening of boarders to the east countries, requires new efforts in traffic policy. In the city agglomerations the motor traffic is nearly collapsing. The increase of motor traffic is the reason for a considerable degradation of environment, especially by noise and air pollution. For the region of Stuttgart the problems and possibilities of counter-measures are discussed. (author)

  11. Quantifying the impact of traffic-related air pollution on the indoor air quality of a naturally ventilated building.

    Science.gov (United States)

    Tong, Zheming; Chen, Yujiao; Malkawi, Ali; Adamkiewicz, Gary; Spengler, John D

    2016-01-01

    Improper natural ventilation practices may deteriorate indoor air quality when in close proximity to roadways, although the intention is often to reduce energy consumption. In this study, we employed a CFD-based air quality model to quantify the impact of traffic-related air pollution on the indoor air quality of a naturally ventilated building. Our study found that the building envelope restricts dispersion and dilution of particulate matter. The indoor concentration in the baseline condition located 10m away from the roadway is roughly 16-21% greater than that at the edge of the roadway. The indoor flow recirculation creates a well-mixed zone with little variation in fine particle concentration (i.e., 253nm). For ultrafine particles (building, particle size, wind condition, and window size and location. A break-even point is observed at D'~2.1 (normalized distance from the roadway by the width of the road). The indoor particle concentration is greater than that at the highway where D'building planning, the distance from the roadway and the ambient wind condition need to be considered at the early design stage whereas the size and location of the window openings, the interior layout, and the placement of fresh air intakes are important to the indoor air quality of existing buildings adjacent to roadways. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Calculation of the Green functions by the coupling constant dispersion relations

    International Nuclear Information System (INIS)

    Bogomalny, E.B.

    1977-01-01

    The discontinuities of the Green functions on the cut in the complex plane of the coupling constant are calculated by the steepest descent method. The saddle points are given by the solutions of the classical field equations at those values of the coupling constant for which the classical theory has no ground state. The Green functions at the physical values of the coupling constant are determined by dispersion relations. (Auth.)

  13. A Comparison of Exposure Metrics for Traffic-Related Air Pollutants: Application to Epidemiology Studies in Detroit, Michigan

    Science.gov (United States)

    Vehicles are major sources of air pollutant emissions, and individuals living near large roads endure high exposures and health risks associated with traffic-related air pollutants. Air pollution epidemiology, health risk, environmental justice, and transportation planning studi...

  14. Direct calculation of self-consistent π bond orders in conjugated systems and pairing relations

    International Nuclear Information System (INIS)

    Castro, A.F.

    1982-01-01

    Pairing relations in excited states of conjugated systems which satisfy to a given symmetry with a Pariser-Parr-Pople-like (PPP) calculation are studied. Six π - electron systems are considered having a symmetry axis which does not cross π centers following a treatment which permits the direct obtainment of the bond order matrix based on Hall's method. Pairing relations are looked for, too, using particular solutions when U(3) groups is applied. Pyridazine molecules are used in order to test the results. (L.C.) [pt

  15. Accurate thermodynamic relations of the melting temperature of nanocrystals with different shapes and pure theoretical calculation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jinhua; Fu, Qingshan; Xue, Yongqiang, E-mail: xyqlw@126.com; Cui, Zixiang

    2017-05-01

    Based on the surface pre-melting model, accurate thermodynamic relations of the melting temperature of nanocrystals with different shapes (tetrahedron, cube, octahedron, dodecahedron, icosahedron, nanowire) were derived. The theoretically calculated melting temperatures are in relative good agreements with experimental, molecular dynamic simulation and other theoretical results for nanometer Au, Ag, Al, In and Pb. It is found that the particle size and shape have notable effects on the melting temperature of nanocrystals, and the smaller the particle size, the greater the effect of shape. Furthermore, at the same equivalent radius, the more the shape deviates from sphere, the lower the melting temperature is. The value of melting temperature depression of cylindrical nanowire is just half of that of spherical nanoparticle with an identical radius. The theoretical relations enable one to quantitatively describe the influence regularities of size and shape on the melting temperature and to provide an effective way to predict and interpret the melting temperature of nanocrystals with different sizes and shapes. - Highlights: • Accurate relations of T{sub m} of nanocrystals with various shapes are derived. • Calculated T{sub m} agree with literature results for nano Au, Ag, Al, In and Pb. • ΔT{sub m} (nanowire) = 0.5ΔT{sub m} (spherical nanocrystal). • The relations apply to predict and interpret the melting behaviors of nanocrystals.

  16. Thermal conductivity calculation of nano-suspensions using Green–Kubo relations with reduced artificial correlations

    International Nuclear Information System (INIS)

    Muraleedharan, Murali Gopal; Yang, Vigor; Sundaram, Dilip Srinivas; Henry, Asegun

    2017-01-01

    The presence of artificial correlations associated with Green–Kubo (GK) thermal conductivity calculations is investigated. The thermal conductivity of nano-suspensions is calculated by equilibrium molecular dynamics (EMD) simulations using GK relations. Calculations are first performed for a single alumina (Al 2 O 3 ) nanoparticle dispersed in a water medium. For a particle size of 1 nm and volume fraction of 9%, results show enhancements as high as 235%, which is much higher than the Maxwell model predictions. When calculations are done with multiple suspended particles, no such anomalous enhancement is observed. This is because the vibrations in alumina crystal can act as low frequency perturbations, which can travel long distances through the surrounding water medium, characterized by higher vibration frequencies. As a result of the periodic boundaries, they re-enter the system resulting in a circular resonance of thermal fluctuations between the alumina particle and its own image, eventually leading to artificial correlations in the heat current autocorrelation function (HCACF), which when integrated yields abnormally high thermal conductivities. Adding more particles presents ‘obstacles’ with which the fluctuations interact and get dissipated, before they get fed back to the periodic image. A systematic study of the temporal evolution of HCACF indicates that the magnitude and oscillations of artificial correlations decrease substantially with increase in the number of suspended nanoparticles. (paper)

  17. Uncertainty evaluation of the kerma in the air, related to the active volume in the ionization chamber of concentric cylinders, by Monte Carlo simulation

    International Nuclear Information System (INIS)

    Lo Bianco, A.S.; Oliveira, H.P.S.; Peixoto, J.G.P.

    2009-01-01

    To implant the primary standard of the magnitude kerma in the air for X-ray between 10 - 50 keV, the National Metrology Laboratory of Ionizing Radiations (LNMRI) must evaluate all the uncertainties of measurement related with Victtoren chamber. So, it was evaluated the uncertainty of the kerma in the air consequent of the inaccuracy in the active volume of the chamber using the calculation of Monte Carlo as a tool through the Penelope software

  18. Stormwater Management: Calculation of Traffic Area Runoff Loads and Traffic Related Emissions

    Directory of Open Access Journals (Sweden)

    Maximilian Huber

    2016-07-01

    Full Text Available Metals such as antimony, cadmium, chromium, copper, lead, nickel, and zinc can be highly relevant pollutants in stormwater runoff from traffic areas because of their occurrence, toxicity, and non-degradability. Long-term measurements of their concentrations, the corresponding water volumes, the catchment areas, and the traffic volumes can be used to calculate specific emission loads and annual runoff loads that are necessary for mass balances. In the literature, the annual runoff loads are often specified by a distinct catchment area (e.g., g/ha. These loads were summarized and discussed in this paper for all seven metals and three types of traffic areas (highways, parking lots, and roads; 45 sites. For example, the calculated median annual runoff loads of all sites are 355 g/ha for copper, 110 g/ha for lead (only data of the 21st century, and 1960 g/ha for zinc. In addition, historical trends, annual variations, and site-specific factors were evaluated for the runoff loads. For Germany, mass balances of traffic related emissions and annual heavy metal runoff loads from highways and total traffic areas were calculated. The influences on the mass fluxes of the heavy metal emissions and the runoff pollution were discussed. However, a statistical analysis of the annual traffic related metal fluxes, in particular for different traffic area categories and land uses, is currently not possible because of a lack of monitoring data.

  19. The calculation of relative output factor and depth dose for irregular electron fields in water

    International Nuclear Information System (INIS)

    Dunscombe, Peter; McGhee, Peter; Chu, Terence

    1996-01-01

    Purpose: A technique, based on sector integration and interpolation, has been developed for the computation of both relative output factor and depth dose of irregular electron fields in water. The purpose of this study was to determine the minimum experimental data set required for the technique to yield results within accepted dosimetric tolerances. Materials and Methods: PC based software has been written to perform the calculations necessary to dosimetrically characterize irregular shaped electron fields. The field outline is entered via digitiser and the SSD and energy via the keyboard. The irregular field is segmented into sectors of specified angle (2 deg. was used for this study) and the radius of each sector computed. The central ray depth dose is reconstructed by summing the contributions from each sector deduced from calibration depth doses measured for circular fields. Relative output factors and depth doses at SSDs at which calibrations were not performed are found by interpolation. Calibration data were measured for circular fields from 2 to 9 cm diameter at 100, 105, 110, and 115 cm SSD. A clinical cut out can be characterized in less than 2 minutes including entry of the outline using this software. The performance of the technique was evaluated by comparing calculated relative output factors, surface dose and the locations of d 80 , d 50 and d 20 with experimental measurements on a variety of cut out shapes at 9 and 18 MeV. The calibration data set (derived from circular cut outs) was systematically reduced to identify the minimum required to yield an accuracy consistent with current recommendations. Results: The figure illustrates the ability of the technique to calculate the depth dose for an irregular field (shown in the insert). It was found that to achieve an accuracy of 2% in relative output factor and 2% or 2 mm (our criterion) in percentage depth dose, calibration data from five circular fields at the four SSDs spanning the range 100-115 cm

  20. To address surface reaction network complexity using scaling relations machine learning and DFT calculations

    International Nuclear Information System (INIS)

    Ulissi, Zachary W.; Medford, Andrew J.; Bligaard, Thomas; Nørskov, Jens K.

    2017-01-01

    Surface reaction networks involving hydrocarbons exhibit enormous complexity with thousands of species and reactions for all but the very simplest of chemistries. We present a framework for optimization under uncertainty for heterogeneous catalysis reaction networks using surrogate models that are trained on the fly. The surrogate model is constructed by teaching a Gaussian process adsorption energies based on group additivity fingerprints, combined with transition-state scaling relations and a simple classifier for determining the rate-limiting step. The surrogate model is iteratively used to predict the most important reaction step to be calculated explicitly with computationally demanding electronic structure theory. Applying these methods to the reaction of syngas on rhodium(111), we identify the most likely reaction mechanism. Lastly, propagating uncertainty throughout this process yields the likelihood that the final mechanism is complete given measurements on only a subset of the entire network and uncertainty in the underlying density functional theory calculations.

  1. Investigation of metal/carbon-related materials for fuel cell applications by electronic structure calculations

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Ki-jeong [Korea Research Institute of Chemical Technology, P.O.Box 107, Yuseong, Daejeon 305-600 (Korea, Republic of)]. E-mail: kong@krict.re.kr; Choi, Youngmin [Korea Research Institute of Chemical Technology, P.O.Box 107, Yuseong, Daejeon 305-600 (Korea, Republic of); Ryu, Beyong-Hwan [Korea Research Institute of Chemical Technology, P.O.Box 107, Yuseong, Daejeon 305-600 (Korea, Republic of); Lee, Jeong-O [Korea Research Institute of Chemical Technology, P.O.Box 107, Yuseong, Daejeon 305-600 (Korea, Republic of); Chang, Hyunju [Korea Research Institute of Chemical Technology, P.O.Box 107, Yuseong, Daejeon 305-600 (Korea, Republic of)

    2006-07-15

    The potential of carbon-related materials, such as carbon nanotubes (CNTs) and graphite nanofibers (GNFs), supported metal catalysts as an electrode for fuel cell application was investigated using the first-principle electronic structure calculations. The stable binding geometries and energies of metal catalysts are determined on the CNT surface and the GNF edge. The catalyst metal is more tightly bound to the GNF edge than to the CNT surface because of the existence of active dangling bonds of edge carbon atoms. The diffusion barrier of metal atoms on the surface and edge is also obtained. From our calculation results, we have found that high dispersity is achievable for GNF due to high barrier against the diffusion of metal atoms, while CNT appears less suitable. The GNF with a large edge-to-wall ratio is more suitable for the high-performance electrode than perfect crystalline graphite or CNT.

  2. Investigation of metal/carbon-related materials for fuel cell applications by electronic structure calculations

    International Nuclear Information System (INIS)

    Kong, Ki-jeong; Choi, Youngmin; Ryu, Beyong-Hwan; Lee, Jeong-O; Chang, Hyunju

    2006-01-01

    The potential of carbon-related materials, such as carbon nanotubes (CNTs) and graphite nanofibers (GNFs), supported metal catalysts as an electrode for fuel cell application was investigated using the first-principle electronic structure calculations. The stable binding geometries and energies of metal catalysts are determined on the CNT surface and the GNF edge. The catalyst metal is more tightly bound to the GNF edge than to the CNT surface because of the existence of active dangling bonds of edge carbon atoms. The diffusion barrier of metal atoms on the surface and edge is also obtained. From our calculation results, we have found that high dispersity is achievable for GNF due to high barrier against the diffusion of metal atoms, while CNT appears less suitable. The GNF with a large edge-to-wall ratio is more suitable for the high-performance electrode than perfect crystalline graphite or CNT

  3. Seasonal Variations of Indoor Microbial Exposures and Their Relation to Temperature, Relative Humidity, and Air Exchange Rate

    DEFF Research Database (Denmark)

    Frankel, Mika; Bekö, Gabriel; Timm, Michael

    2012-01-01

    with temperature, relative humidity, and air exchange rates in Danish homes. Airborne inhalable dust was sampled in five Danish homes throughout the four seasons of 1 year (indoors, n = 127; outdoors, n = 37). Measurements included culturable fungi and bacteria, endotoxin, N-acetyl-beta-d-glucosaminidase, total...... inflammatory potential, particles (0.75 to 15 μm), temperature, relative humidity, and air exchange rates. Significant seasonal variation was found for all indoor microbial exposures, excluding endotoxin. Indoor fungi peaked in summer (median, 235 CFU/m3) and were lowest in winter (median, 26 CFU/m3). Indoor...... of inhalable dust and number of particles. Temperature and air exchange rates were positively associated with fungi and N-acetyl-beta-d-glucosaminidase and negatively with bacteria and the total inflammatory potential. Although temperature, relative humidity, and air exchange rates were significantly...

  4. A computer code for the prediction of mill gases and hot air distribution between burners sections as input parameters for 3D CFD furnace calculation

    International Nuclear Information System (INIS)

    Tucakovic, Dragan; Zivanovic, Titoslav; Beloshevic, Srdjan

    2006-01-01

    Current computer technology development enables application of powerful software packages that can provide a reliable insight into real operating conditions of a steam boiler in the Thermal Power Plant. Namely, an application of CFD code to the 3D analysis of combustion and heat transfer in a furnace provides temperature, velocity and concentration fields in both cross sectional and longitudinal planes of the observed furnace. In order to obtain reliable analytical results, which corresponds to real furnace conditions, it is necessary to accurately predict a distribution of mill gases and hot air between burners' sections, because these parameters are input values for the furnace 3D calculation. Regarding these tasks, the computer code for the prediction of mill gases and hot air distribution has been developed at the Department for steam boilers of the Faculty of Mechanical Engineering in Belgrade. The code is based on simultaneous calculations of material and heat balances for fan mill and air tracts. The aim of this paper is to present a methodology of performed calculations and results obtained for the steam boiler furnace of 350 MWe Thermal Power Plant equipped with eight fan mills. Key words: mill gases, hot air, aerodynamic calculation, air tract, mill tract.

  5. Considerations and calculations on the breakup of jets and drops of melt related to premixing

    Energy Technology Data Exchange (ETDEWEB)

    Buerger, M.; Berg, E. von; Buck, M. [Inst. fuer Kernenergetik und Energiesysteme (IKE), Univ. of Stuttgart, Pfaffenwaldring 31, 70569 Stuttgart (Germany)

    1998-01-01

    Various descriptions of jet and drop breakup are applied in premixing codes, presently. The main task is to check these descriptions over a wide range of conditions in order to assure extrapolation capabilities for the codes. Jet breakup under non-boiling conditions is relatively well described by IKEJET, based on Conte/Miles (CM) instability description and a relatively detailed stripping model, in contrast to using Kelvin/Helmholtz (KH) theory. Remaining open questions are elaborated. Especially, thick jet behavior with dominance of stripping even at small relative velocities must be distinguished from thin jets with coarse breakup. The application of IKEJET to cases with jet breakup under strong film boiling yielded significantly too little fragmentation. As a possible explanation line, multiphase effects on the wave growth and stripping are considered, due to entrainment of melt and water. Parametric checking calculations are performed with a strongly simplified approach for PREMIX and FARO experiments in order to reveal main effects and the possible physical explanation features as a basis for extended modelling. The results indicate that jet breakup may be essentially sufficient to explain the experimental behavior. Rather coalescence than further drop breakup may be expected. This is also indicated by calculations with IKE drop breakup models. (author)

  6. Challenges and future direction of molecular research in air pollution-related lung cancers.

    Science.gov (United States)

    Shahadin, Maizatul Syafinaz; Ab Mutalib, Nurul Syakima; Latif, Mohd Talib; Greene, Catherine M; Hassan, Tidi

    2018-04-01

    Hazardous air pollutants or chemical release into the environment by a variety of natural and/or anthropogenic activities may give adverse effects to human health. Air pollutants such as sulphur dioxide (SO2), nitrogen oxides (NOx), carbon monoxide (CO), heavy metals and particulate matter (PM) affect number of different human organs, especially the respiratory system. The International Agency for Research on Cancer (IARC) reported that ambient air pollution is a cause of lung cancer. Recently, the agency has classified outdoor air pollution as well as PM air pollution as Group 1 carcinogens. In addition, several epidemiological studies have shown a positive association between air pollutants to lung cancer risks and mortality. However, there are only a few studies examining the molecular effects of air pollution exposure specifically in lung cancer due to multiple challenges to mimic air pollution exposure in basic experimentation. Another major issue is the lack of adequate adjustments for exposure misclassification as air pollution may differ temporo-spatially and socioeconomically. Thus, the purpose of this paper is to review the current molecular understanding of air pollution-related lung cancer and potential future direction in this challenging yet important research field. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Statistical elements in calculations procedures for air quality control; Elementi di statistica nelle procedure di calcolo per il controllo della qualita' dell'aria

    Energy Technology Data Exchange (ETDEWEB)

    Mura, M.C. [Istituto Superiore di Sanita' , Laboratorio di Igiene Ambientale, Rome (Italy)

    2001-07-01

    The statistical processing of data resulting from the monitoring of chemical atmospheric pollution aimed at air quality control is presented. The form of procedural models may offer a practical instrument to the operators in the sector. The procedural models are modular and can be easily integrated with other models. They include elementary calculation procedures and mathematical methods for statistical analysis. The calculation elements have been developed by probabilistic induction so as to relate them to the statistical analysis. The calculation elements have been developed by probabilistic induction so as to relate them to the statistical models, which are the basis of the methods used for the study and the forecast of atmospheric pollution. This report is part of the updating and training activity that the Istituto Superiore di Sanita' has been carrying on for over twenty years, addressed to operators of the environmental field. [Italian] Il processo di elaborazione statistica dei dati provenienti dal monitoraggio dell'inquinamento chimico dell'atmosfera, finalizzato al controllo della qualita' dell'aria, e' presentato in modelli di procedure al fine di fornire un sintetico strumento di lavoro agli operatori del settore. I modelli di procedure sono modulari ed integrabili. Includono gli elementi di calcolo elementare ed i metodi statistici d'analisi. Gli elementi di calcolo sono sviluppati con metodo d'induzione probabilistica per collegarli ai modelli statistici, che sono alla base dei metodi d'analisi nello studio del fenomeno dell'inquinamento atmosferico anche a fini previsionali. Il rapporto si inserisce nell'attivita' di aggiornamento e di formazione che fin dagli anni ottanta l'Istituto Superiore di Sanita' indirizza agli operatori del settore ambientale.

  8. Relative Binding Free Energy Calculations in Drug Discovery: Recent Advances and Practical Considerations.

    Science.gov (United States)

    Cournia, Zoe; Allen, Bryce; Sherman, Woody

    2017-12-26

    Accurate in silico prediction of protein-ligand binding affinities has been a primary objective of structure-based drug design for decades due to the putative value it would bring to the drug discovery process. However, computational methods have historically failed to deliver value in real-world drug discovery applications due to a variety of scientific, technical, and practical challenges. Recently, a family of approaches commonly referred to as relative binding free energy (RBFE) calculations, which rely on physics-based molecular simulations and statistical mechanics, have shown promise in reliably generating accurate predictions in the context of drug discovery projects. This advance arises from accumulating developments in the underlying scientific methods (decades of research on force fields and sampling algorithms) coupled with vast increases in computational resources (graphics processing units and cloud infrastructures). Mounting evidence from retrospective validation studies, blind challenge predictions, and prospective applications suggests that RBFE simulations can now predict the affinity differences for congeneric ligands with sufficient accuracy and throughput to deliver considerable value in hit-to-lead and lead optimization efforts. Here, we present an overview of current RBFE implementations, highlighting recent advances and remaining challenges, along with examples that emphasize practical considerations for obtaining reliable RBFE results. We focus specifically on relative binding free energies because the calculations are less computationally intensive than absolute binding free energy (ABFE) calculations and map directly onto the hit-to-lead and lead optimization processes, where the prediction of relative binding energies between a reference molecule and new ideas (virtual molecules) can be used to prioritize molecules for synthesis. We describe the critical aspects of running RBFE calculations, from both theoretical and applied perspectives

  9. The Effect of Material Homogenization in Calculating the Gamma-Ray dose from Spent PWR Fuel Pins in an Air Medium

    International Nuclear Information System (INIS)

    TH Trumbull

    2005-01-01

    The effect of material homogenization on the calculated dose rate was studied for several arrangements of typical PWR spent fuel pins in an air medium using the Monte Carlo code, MCNP. The models analyzed increased in geometric complexity, beginning with a single fuel pin, progressing to ''small'' lattices, i.e., 3x3, 5x5, 7x7 fuel pins, and culminating with a full 17x17 pin PWR bundle analysis. The fuel pin dimensions and compositions were taken directly from a previous study and efforts were made to parallel this study by specifying identical flux-to-dose functions and gamma-ray source spectra. The analysis shows two competing components to the overall effect of material homogenization on calculated dose rate. Homogenization of pin lattices tends to lower the effect of radiation ''channeling'' but increase the effect of ''source redistribution.'' Depending on the size of the lattice and location of the detectors, the net effect of material homogenization on dose rate can be insignificant or range from a 6% decrease to a 35% increase relative to the detailed geometry model

  10. Developmental Neurotoxicity of Traffic-Related Air Pollution: Focus on Autism.

    Science.gov (United States)

    Costa, Lucio G; Chang, Yu-Chi; Cole, Toby B

    2017-06-01

    Epidemiological and animal studies suggest that air pollution may negatively affect the central nervous system (CNS) and contribute to CNS diseases. Traffic-related air pollution is a major contributor to global air pollution, and diesel exhaust (DE) is its most important component. Several studies suggest that young individuals may be particularly susceptible to air pollution-induced neurotoxicity and that perinatal exposure may cause or contribute to developmental disabilities and behavioral abnormalities. In particular, a number of recent studies have found associations between exposures to traffic-related air pollution and autism spectrum disorders (ASD), which are characterized by impairment in socialization and in communication and by the presence of repetitive and unusual behaviors. The cause(s) of ASD are unknown, and while it may have a hereditary component, environmental factors are increasingly suspected as playing a pivotal role in its etiology, particularly in genetically susceptible individuals. Autistic children present higher levels of neuroinflammation and systemic inflammation, which are also hallmarks of exposure to traffic-related air pollution. Gene-environment interactions may play a relevant role in determining individual susceptibility to air pollution developmental neurotoxicity. Given the worldwide presence of elevated air pollution, studies on its effects and mechanisms on the developing brain, genetic susceptibility, role in neurodevelopmental disorders, and possible therapeutic interventions are certainly warranted.

  11. Calculation of NO2 concentration in air from the point source Tepláreň Košice

    Directory of Open Access Journals (Sweden)

    Jozef Mačala

    2007-06-01

    Full Text Available The most threatened part of environment is air and its pollution increases rapidly. In the local rate, the weight of air pollution increases by reason of a more intensive influence on the human population. The problem is significant mostly in urban areas, places with the biggest concentration of peoples, industry and transport. The greatest producers of air pollution are various parts of industry, heat production and traffic. For a complex valuation, the influence of particular parts of industry is needed to know the sources of air pollution in the specific area. Only with a knowledge, it is possible to evaluate a spotted area in terms of air quality.

  12. Some features of excited states density matrix calculation and their pairing relations in conjugated systems

    International Nuclear Information System (INIS)

    Giambiagi, M.S. de; Giambiagi, M.

    1982-01-01

    Direct PPP-type calculations of self-consistent (SC) density matrices for excited states are described and the corresponding 'thawn' molecular orbitals (MO) are discussed. Special attention is addressed to particular solutions arising in conjugated systems of a certain symmetry, and to their chemical implications. The U(2) and U(3) algebras are applied respectively to the 4-electron and 6-electron cases: a natural separation of excited states in different cases follows. A simple approach to the convergence problem for excited states is given. The complementarity relations, an alternative formulation of the pairing theorem valid for heteromolecules and non-alternant systems, allow some fruitful experimental applications. Together with the extended pairing relations shown here, they may help to rationalize general trends. (Author) [pt

  13. DFT/GIAO calculations of the relative contributions of hyperconjugation to the chemical shifts of ethanol

    International Nuclear Information System (INIS)

    Carneiro, J. Walkimar de M.; Dias, Jacques F.; Seidl, Peter R.; Tostes, J. Glauco R.

    2002-01-01

    Our previous DFT/GIAO calculations on different types of alcohols reveal that the rotation of the hydroxyl group can affect the chemical shift of carbons and hydrogens close to the substituent in different ways. Besides the steric and electrostatic effects that have been widely studied, hyperconjugation with the lone pairs on oxygen of the hydroxyl group leads to changes in bond lengths and angles as well as to different charge distributions. As all three of these factors also affect chemical shifts, we undertook a systematic investigation of their relative contributions to the chemical shifts of ethanol, a molecule in which there is minimum interference among these factors. Calculations by the B3LYP method at the 6-31G(d) level for ethanol conformers corresponding to a rotation around the carbon-oxygen bond at 30 dec increments are used to show how relative contributions vary with the dihedral angle formed between the carbon-carbon and oxygen-hydrogen bonds (C-C-O-H). Largest contributions to carbon chemical shifts can be attributed to changes in bond lengths while for hydrogen chemical shifts also contribute significantly differences in charge distribution. (author)

  14. Calculation of prevalence estimates through differential equations: application to stroke-related disability.

    Science.gov (United States)

    Mar, Javier; Sainz-Ezkerra, María; Moler-Cuiral, Jose Antonio

    2008-01-01

    Neurological diseases now make up 6.3% of the global burden of disease mainly because they cause disability. To assess disability, prevalence estimates are needed. The objective of this study is to apply a method based on differential equations to calculate the prevalence of stroke-related disability. On the basis of a flow diagram, a set of differential equations for each age group was constructed. The linear system was solved analytically and numerically. The parameters of the system were obtained from the literature. The model was validated and calibrated by comparison with previous results. The stroke prevalence rate per 100,000 men was 828, and the rate for stroke-related disability was 331. The rates steadily rose with age, but the group between the ages of 65 and 74 years had the highest total number of individuals. Differential equations are useful to represent the natural history of neurological diseases and to make possible the calculation of the prevalence for the various states of disability. In our experience, when compared with the results obtained by Markov models, the benefit of the continuous use of time outweighs the mathematical requirements of our model. (c) 2008 S. Karger AG, Basel.

  15. Calculation of the relative efficiency of thermoluminescent detectors to space radiation

    International Nuclear Information System (INIS)

    Bilski, P.

    2011-01-01

    Thermoluminescent (TL) detectors are often used for measurements of radiation doses in space. While space radiation is composed of a mixture of heavy charged particles, the relative TL efficiency depends on ionization density. The question therefore arises: what is the relative efficiency of TLDs to the radiation present in space? In the attempt to answer this question, the relative TL efficiency of two types of lithium fluoride detectors for space radiation has been calculated, based on the theoretical space spectra and the experimental values of TL efficiency to ion beams. The TL efficiency of LiF:Mg,Ti detectors for radiation encountered at typical low-Earth’s orbit was found to be close to unity, justifying a common application of these TLDs to space dosimetry. The TL efficiency of LiF:Mg,Cu,P detectors is significantly lower. It was found that a shielding may have a significant influence on the relative response of TLDs, due to changes caused in the radiation spectrum. In case of application of TLDs outside the Earth’s magnetosphere, one should expect lower relative efficiency than at the low-Earth’s orbit.

  16. Calculating statistical distributions from operator relations: The statistical distributions of various intermediate statistics

    International Nuclear Information System (INIS)

    Dai, Wu-Sheng; Xie, Mi

    2013-01-01

    In this paper, we give a general discussion on the calculation of the statistical distribution from a given operator relation of creation, annihilation, and number operators. Our result shows that as long as the relation between the number operator and the creation and annihilation operators can be expressed as a † b=Λ(N) or N=Λ −1 (a † b), where N, a † , and b denote the number, creation, and annihilation operators, i.e., N is a function of quadratic product of the creation and annihilation operators, the corresponding statistical distribution is the Gentile distribution, a statistical distribution in which the maximum occupation number is an arbitrary integer. As examples, we discuss the statistical distributions corresponding to various operator relations. In particular, besides the Bose–Einstein and Fermi–Dirac cases, we discuss the statistical distributions for various schemes of intermediate statistics, especially various q-deformation schemes. Our result shows that the statistical distributions corresponding to various q-deformation schemes are various Gentile distributions with different maximum occupation numbers which are determined by the deformation parameter q. This result shows that the results given in much literature on the q-deformation distribution are inaccurate or incomplete. -- Highlights: ► A general discussion on calculating statistical distribution from relations of creation, annihilation, and number operators. ► A systemic study on the statistical distributions corresponding to various q-deformation schemes. ► Arguing that many results of q-deformation distributions in literature are inaccurate or incomplete

  17. Core Values: A History of Values-Related Initiatives in the Air Force

    National Research Council Canada - National Science Library

    Dierker, Gregory

    1997-01-01

    .... This study specifically examines two of the assumptions made in the current Air Force Core Values initiative against the historic values-related initiatives to identify any differences that have occurred over time...

  18. Fisher Sand & Gravel New Mexico, Inc. General Air Quality Permit: Related Documents

    Science.gov (United States)

    Documents related to the Fisher Sand & Gravel – New Mexico, Inc., Grey Mesa Gravel Pit General Air Quality Permit for New or Modified Minor Source Stone Quarrying, Crushing, and Screening Facilities in Indian Country.

  19. Bicyclists' Uptake of Traffic-Related Air Pollution: Effects of the Urban Transportation System

    Science.gov (United States)

    2014-10-27

    While bicyclists and other active travelers obtain health benefits from increased physical activity, they also risk uptake of traffic-related air pollution. But pollution uptake by urban bicyclists is not well understood due to a lack of direct measu...

  20. Spatiotemporally resolved air exchange rate as a modifier of acute air pollution-related morbidity in Atlanta.

    Science.gov (United States)

    Sarnat, Jeremy A; Sarnat, Stefanie Ebelt; Flanders, W Dana; Chang, Howard H; Mulholland, James; Baxter, Lisa; Isakov, Vlad; Özkaynak, Halûk

    2013-01-01

    Epidemiological studies frequently use central site concentrations as surrogates of exposure to air pollutants. Variability in air pollutant infiltration due to differential air exchange rates (AERs) is potentially a major factor affecting the relationship between central site concentrations and actual exposure, and may thus influence observed health risk estimates. In this analysis, we examined AER as an effect modifier of associations between several urban air pollutants and corresponding emergency department (ED) visits for asthma and wheeze during a 4-year study period (January 1999-December 2002) for a 186 ZIP code area in metro Atlanta. We found positive associations for the interaction between AER and pollution on asthma ED visits for both carbon monoxide (CO) and nitrogen oxides (NO(x)), indicating significant or near-significant effect modification by AER on the pollutant risk-ratio estimates. In contrast, the interaction term between particulate matter (PM)(2.5) and AER on asthma ED visits was negative and significant. However, alternative distributional tertile analyses showed PM(2.5) and AER epidemiological model results to be similar to those found for NOx and CO (namely, increasing risk ratios (RRs) with increasing AERs when ambient PM(2.5) concentrations were below the highest tertile of their distribution). Despite the fact that ozone (O(3)) was a strong independent predictor of asthma ED visits in our main analysis, we found no O(3)-AER effect modification. To our knowledge, our findings for CO, NOx, and PM(2.5) are the first to provide an indication of short-term (i.e., daily) effect modification of multiple air pollution-related risk associations with daily changes in AER. Although limited to one outcome category in a single large urban locale, the findings suggest that the use of relatively simple and easy-to-derive AER surrogates may reflect intraurban differences in short-term exposures to pollutants of ambient origin.

  1. Community Perceptions of Air Pollution and Related Health Risks in Nairobi Slums

    Science.gov (United States)

    Egondi, Thaddaeus; Kyobutungi, Catherine; Ng, Nawi; Muindi, Kanyiva; Oti, Samuel; van de Vijver, Steven; Ettarh, Remare; Rocklöv, Joacim

    2013-01-01

    Air pollution is among the leading global risks for mortality and responsible for increasing risk for chronic diseases. Community perceptions on exposure are critical in determining people’s response and acceptance of related policies. Therefore, understanding people’ perception is critical in informing the design of appropriate intervention measures. The aim of this paper was to establish levels and associations between perceived pollution and health risk perception among slum residents. A cross-sectional study of 5,317 individuals aged 35+ years was conducted in two slums of Nairobi. Association of perceived score and individual characteristics was assessed using linear regression. Spatial variation in the perceived levels was determined through hot spot analysis using ArcGIS. The average perceived air pollution level was higher among residents in Viwandani compared to those in Korogocho. Perceived air pollution level was positively associated with perceived health risks. The majority of respondents were exposed to air pollution in their place of work with 66% exposed to at least two sources of air pollution. Less than 20% of the respondents in both areas mentioned sources related to indoor pollution. The perceived air pollution level and related health risks in the study community were lowamong the residents indicating the need for promoting awareness on air pollution sources and related health risks. PMID:24157509

  2. Assessing urban air quality and its relation with radon (222Rn)

    International Nuclear Information System (INIS)

    Zoran, Maria; Savastru, Dan; Dida, Adrian

    2016-01-01

    This paper focuses on the assessment of air quality and its relation with radon ( 222 Rn) for Bucharest metropolitan area in Romania. Specifically, daily mean concentrations of particle matter (PM2.5, PM10), ozone (O 3 ), nitrogen dioxide (NO 2 ), sulphur dioxide (SO 2 ) and global air quality indices have been analyzed in relation with radon ( 222 Rn) concentrations measured in the air near the ground with AlphaGUARD Radon Monitoring System and CR-39 SSNTDs during 2012 year. Such new information is required by atmospheric sciences to prove suitability of 222 Rn as a tracer for atmospheric dynamics analysis as well as by epidemiological and radiological protection studies. (author)

  3. Cultivar Differences in Plant Transpiration Rate at High Relative Air Humidity Are Not Related to Genotypic Variation in Stomatal Responsiveness

    DEFF Research Database (Denmark)

    Gebraegziabher, Habtamu Giday; Kjær, Katrine Heinsvig; Ottosen, Carl-Otto

    2015-01-01

    Plants grown at high relative air humidity (RH) often show disturbed water relations due to less responsive stomata. The attenuation of stomatal responsiveness as a result of high RH during leaf expansion depends on the cultivar. We hypothesized that tolerant cultivars to high RH experience a low...

  4. Measurements and calculations of air activation in the NuMI neutrino production facility at Fermilab with the 120-GeV proton beam on target

    Energy Technology Data Exchange (ETDEWEB)

    Rakhno, I. L.; Hylen, J.; Kasper, P.; Mokhov, N. V.; Quinn, M.; Striganov, S. I.; Vaziri, K.

    2018-01-01

    Measurements and calculations of the air activation at a high-energy proton accelerator are described. The quantity of radionuclides released outdoors depends on operation scenarios including details of the air exchange inside the facility. To improve the prediction of the air activation levels, the MARS15 Monte Carlo code radionuclide production model was modified to be used for these studies. Measurements were done to benchmark the new model and verify its use in optimization studies for the new DUNE experiment at the Long Baseline Neutrino Facility (LBNF) at Fermilab. The measured production rates for the most important radionuclides – 11C, 13N, 15O and 41Ar – are in a good agreement with those calculated with the improved MARS15 code.

  5. Measurements and calculations of air activation in the NuMI neutrino production facility at Fermilab with the 120-GeV proton beam on target

    Science.gov (United States)

    Rakhno, I. L.; Hylen, J.; Kasper, P.; Mokhov, N. V.; Quinn, M.; Striganov, S. I.; Vaziri, K.

    2018-01-01

    Measurements and calculations of the air activation at a high-energy proton accelerator are described. The quantity of radionuclides released outdoors depends on operation scenarios including details of the air exchange inside the facility. To improve the prediction of the air activation levels, the MARS15 Monte Carlo code radionuclide production model was modified to be used for these studies. Measurements were done to benchmark the new model and verify its use in optimization studies for the new DUNE experiment at the Long Baseline Neutrino Facility (LBNF) at Fermilab. The measured production rates for the most important radionuclides - 11C, 13N, 15O and 41Ar - are in a good agreement with those calculated with the improved MARS15 code.

  6. The importance of determining the air exchange rate in flats and buildings for calculations of the averted indoor inhalation doses arising from contaminated outdoor air

    International Nuclear Information System (INIS)

    Jilek, Karel; Thomas, J.; Bulanek, B.; Lenk, J.; Marikova, S.

    2015-01-01

    The indoor-outdoor air exchange rate is an important parameter when refining estimates of the averted inhaled doses to population in houses and buildings after an emergency event resulting in contamination of outdoor air with a radioactive material. The air exchange rates measured in 70 occupied houses and in 20 unoccupied houses using N 2 O as the tracer gas are presented, and the results of modelling the averted doses in the residential buildings for both gaseous and aerosol outdoor contaminants are demonstrated. (orig.)

  7. Calculation of large scale relative permeabilities from stochastic properties of the permeability field and fluid properties

    Energy Technology Data Exchange (ETDEWEB)

    Lenormand, R.; Thiele, M.R. [Institut Francais du Petrole, Rueil Malmaison (France)

    1997-08-01

    The paper describes the method and presents preliminary results for the calculation of homogenized relative permeabilities using stochastic properties of the permeability field. In heterogeneous media, the spreading of an injected fluid is mainly sue to the permeability heterogeneity and viscosity fingering. At large scale, when the heterogeneous medium is replaced by a homogeneous one, we need to introduce a homogenized (or pseudo) relative permeability to obtain the same spreading. Generally, is derived by using fine-grid numerical simulations (Kyte and Berry). However, this operation is time consuming and cannot be performed for all the meshes of the reservoir. We propose an alternate method which uses the information given by the stochastic properties of the field without any numerical simulation. The method is based on recent developments on homogenized transport equations (the {open_quotes}MHD{close_quotes} equation, Lenormand SPE 30797). The MHD equation accounts for the three basic mechanisms of spreading of the injected fluid: (1) Dispersive spreading due to small scale randomness, characterized by a macrodispersion coefficient D. (2) Convective spreading due to large scale heterogeneities (layers) characterized by a heterogeneity factor H. (3) Viscous fingering characterized by an apparent viscosity ration M. In the paper, we first derive the parameters D and H as functions of variance and correlation length of the permeability field. The results are shown to be in good agreement with fine-grid simulations. The are then derived a function of D, H and M. The main result is that this approach lead to a time dependent . Finally, the calculated are compared to the values derived by history matching using fine-grid numerical simulations.

  8. Health status and air pollution related socioeconomic concerns in urban China.

    Science.gov (United States)

    Jiao, Kaishan; Xu, Mengjia; Liu, Meng

    2018-02-05

    China is experiencing environmental issues and related health effects due to its industrialization and urbanization. The health effects associated with air pollution are not just a matter of epidemiology and environmental science research, but also an important social science issue. Literature about the relationship of socioeconomic factors with the environment and health factors is inadequate. The relationship between air pollution exposure and health effects in China was investigated with consideration of the socioeconomic factors. Based on nationwide survey data of China in 2014, we applied the multilevel mixed-effects model to evaluate how socioeconomic status (represented by education and income) contributed to the relationship between self-rated air pollution and self-rated health status at community level and individual level. The findings indicated that there was a non-linear relationship between the community socioeconomic status and community air pollution in urban China, with the highest level of air pollution presented in the communities with moderate socioeconomic status. In addition, health effects associated air pollution in different socioeconomic status groups were not equal. Self-rated air pollution had the greatest impact on self-rated health of the lower socioeconomic groups. With the increase of socioeconomic status, the effect of self-rated air pollution on self-rated health decreased. This study verified the different levels of exposure to air pollution and inequality in health effects among different socioeconomic groups in China. It is imperative for the government to urgently formulate public policies to enhance the ability of the lower socioeconomic groups to circumvent air pollution and reduce the health damage caused by air pollution.

  9. LIGA 2. An improved computer code for the calculation of the local individual submersion dose in off-air plumes from nuclear facilities

    International Nuclear Information System (INIS)

    Rohloff, F.; Brunen, E.

    1981-08-01

    A model is presented to calculate the γ-submersion dose of persons which are exposed to off-air plumes. This model integrates the dose contributions of the spacial volume elements, taking into account the wheather dependent extension of the plume as well as γ-absorption and scattering in air. For data evaluation an essentially improved code LIGA II has been developed, leading to a higher accuracy due to an adequate application of Gauss integrations in MACRO-technique. The short-term propagation factors are calculated for a grid distance of 10-160 km with a logarithmic scale and for a 5 degree angular grid. As is shown by a sensitivity analysis, the mean values of the short-term propagation factors within a sector can be obtained by a simple Simpson-integration. These calculations have been performed explicitly for 10 degree and 30 degree sectors. (orig.) [de

  10. Applied research on air pollution using nuclear-related analytical techniques

    International Nuclear Information System (INIS)

    1994-01-01

    A co-ordinated research programme (CRP) on applied research on air pollution using nuclear-related techniques is a global CRP which will run from 1992-1996, and will build upon the experience gained by the Agency from the laboratory support that it has been providing for several years to BAPMoN - the Background Air Pollution Monitoring Network programme organized under the auspices of the World Meterological Organization. The purpose of this CRP is to promote the use of nuclear analytical techniques in air pollution studies, e.g. NAA, XFR, and PIXE for the analysis of toxic and other trace elements in suspended particulate matter (including air filter samples), rainwater and fog-water samples, and in biological indicators of air pollution (e.g. lichens and mosses). The main purposes of the core programme are i) to support the use of nuclear and nuclear-related analytical techniques for practically-oriented research and monitoring studies on air pollution ii) to identify major sources of air pollution affecting each of the participating countries with particular reference to toxic heavy metals, and iii) to obtain comparative data on pollution levels in areas of high pollution (e.g. a city centre or a populated area downwind of a large pollution source) and low pollution (e.g. rural areas). This document reports the discussions held during the first Research Co-ordination Meeting (RCM) for the CRP which took place at the IAEA Headquarters in Vienna. Refs, figs and tabs

  11. Relative dose efficiencies of antiscatter grids and air gaps in pediatric radiography

    International Nuclear Information System (INIS)

    McDaniel, D.L.; Cohen, G.; Wagner, L.K.; Robinson, L.H.

    1984-01-01

    The relative dose efficiencies (RDE) of various antiscatter grids and air gaps were determined for conditions simulating those found in pediatric radiography, using phantoms representing a newborn child, a 5-yr-old and a 10-yr-old child. Our data indicate than an air gap is best for the newborn, due to the low levels of scatter. The 8:1 fiber grid or 15.2-cm air gap without a grid can improve dose efficiency (DE) for the 5-yr-old child by 20%--25% relative to the 3.3-cm air gap and no-grid technique, while for the 10-yr-old child, DE can be improved by 40% with an 8:1 fiber grid

  12. Health status and air pollution related socioeconomic concerns in urban China

    OpenAIRE

    Jiao, Kaishan; Xu, Mengjia; Liu, Meng

    2018-01-01

    Background China is experiencing environmental issues and related health effects due to its industrialization and urbanization. The health effects associated with air pollution are not just a matter of epidemiology and environmental science research, but also an important social science issue. Literature about the relationship of socioeconomic factors with the environment and health factors is inadequate. The relationship between air pollution exposure and health effects in China was investig...

  13. Experience-Based Mitigation of Age-Related Performance Declines: Evidence from Air Traffic Control

    Science.gov (United States)

    Nunes, Ashley; Kramer, Arthur F.

    2009-01-01

    Previous research has found age-related deficits in a variety of cognitive processes. However, some studies have demonstrated age-related sparing on tasks where individuals have substantial experience, often attained over many decades. Here, the authors examined whether decades of experience in a fast-paced demanding profession, air traffic…

  14. Validation of traffic-related air pollution exposure estimates for long-term studies

    NARCIS (Netherlands)

    Van Roosbroeck, S.

    2007-01-01

    This thesis describes a series of studies that investigate the validity of using outdoor concentrations and/or traffic-related indicator exposure variables as a measure for exposure assessment in epidemiological studies on the long-term effect of traffic-related air pollution. A pilot study was

  15. Effects of long-term exposure to traffic-related air pollution on respiratory and cardiovascular mortality in the Netherlands: the NLCS-AIR study.

    NARCIS (Netherlands)

    Brunekreef, B.|info:eu-repo/dai/nl/067548180; Beelen, R.M.J.|info:eu-repo/dai/nl/30483100X; Hoek, G.|info:eu-repo/dai/nl/069553475; Schouten, L.J.; Bausch-Goldbohm, S.; Fischer, P.; Armstrong, B.; Hughes, E.; Jerrett, M.; v.d. Brandt, P.A.

    2009-01-01

    Evidence is increasing that long-term exposure to ambient air pollution is associated with deaths from cardiopulmonary diseases. In a 2002 pilot study, we reported clear indications that traffic-related air pollution, especially at the local scale, was related to cardiopulmonary mortality in a

  16. Seasonal variations of indoor microbial exposures and their relation to temperature, relative humidity, and air exchange rate.

    Science.gov (United States)

    Frankel, Mika; Bekö, Gabriel; Timm, Michael; Gustavsen, Sine; Hansen, Erik Wind; Madsen, Anne Mette

    2012-12-01

    Indoor microbial exposure has been related to adverse pulmonary health effects. Exposure assessment is not standardized, and various factors may affect the measured exposure. The aim of this study was to investigate the seasonal variation of selected microbial exposures and their associations with temperature, relative humidity, and air exchange rates in Danish homes. Airborne inhalable dust was sampled in five Danish homes throughout the four seasons of 1 year (indoors, n = 127; outdoors, n = 37). Measurements included culturable fungi and bacteria, endotoxin, N-acetyl-beta-d-glucosaminidase, total inflammatory potential, particles (0.75 to 15 μm), temperature, relative humidity, and air exchange rates. Significant seasonal variation was found for all indoor microbial exposures, excluding endotoxin. Indoor fungi peaked in summer (median, 235 CFU/m(3)) and were lowest in winter (median, 26 CFU/m(3)). Indoor bacteria peaked in spring (median, 2,165 CFU/m(3)) and were lowest in summer (median, 240 CFU/m(3)). Concentrations of fungi were predominately higher outdoors than indoors, whereas bacteria, endotoxin, and inhalable dust concentrations were highest indoors. Bacteria and endotoxin correlated with the mass of inhalable dust and number of particles. Temperature and air exchange rates were positively associated with fungi and N-acetyl-beta-d-glucosaminidase and negatively with bacteria and the total inflammatory potential. Although temperature, relative humidity, and air exchange rates were significantly associated with several indoor microbial exposures, they could not fully explain the observed seasonal variations when tested in a mixed statistical model. In conclusion, the season significantly affects indoor microbial exposures, which are influenced by temperature, relative humidity, and air exchange rates.

  17. Modeling of the consequences of an air ingress in the vessel on the source term calculation in a severe accident

    International Nuclear Information System (INIS)

    Beuzet, E.

    2010-01-01

    This work deals with severe accidents in nuclear power plants with an air ingress in the vessel. Air, which is very oxidizing, enhances noticeably ruthenium release, due to a high fuel oxidation. Oxygen affinity is decreasing between zircaloy cladding, fuel and ruthenium which is released from fuel as volatile and radio-toxic oxides. The main objective was to develop models for cladding and fuel oxidation and ruthenium release and implement them in the severe accident code MAAP. For each phenomenon, the literature study contributes to establish numerical models, validated against specific experiments. Cladding oxidation by air leads to a dense zirconia layer and, after cracking, a porous zirconia. Its modelling was validated against QUENCH-10 (KIT) and PARAMETER-SF4 (LUCH) experiments and 'NUREG' oxide mass gain law was selected as the best current compromise. Ruthenium release is modelled as an instantaneous oxide volatilisation at the fuel surface, controlled by fuel oxidation, which is itself based on a surface reaction assumption. These models were validated against a selected set of VERCORS (CEA) experiments. Ruthenium release is well-reproduced, particularly for air and steam atmospheres. To finish, an accidental scenario with air ingress in the vessel was simulated: a first value was given for the time needed to completely release ruthenium still present in core and was compared to the other studies. This simulation underlines the high ruthenium release under air conditions. (author)

  18. Air

    International Nuclear Information System (INIS)

    Gugele, B.; Scheider, J.; Spangl, W.

    2001-01-01

    In recent years several regulations and standards for air quality and limits for air pollution were issued or are in preparation by the European Union, which have severe influence on the environmental monitoring and legislation in Austria. This chapter of the environmental control report of Austria gives an overview about the legal situation of air pollution control in the European Union and in specific the legal situation in Austria. It gives a comprehensive inventory of air pollution measurements for the whole area of Austria of total suspended particulates, ozone, volatile organic compounds, nitrogen oxides, sulfur dioxide, carbon monoxide, heavy metals, benzene, dioxin, polycyclic aromatic hydrocarbons and eutrophication. For each of these pollutants the measured emission values throughout Austria are given in tables and geographical charts, the environmental impact is discussed, statistical data and time series of the emission sources are given and legal regulations and measures for an effective environmental pollution control are discussed. In particular the impact of fossil-fuel power plants on the air pollution is analyzed. (a.n.)

  19. Risk for intracranial pressure increase related to enclosed air in post-craniotomy patients during air ambulance transport: a retrospective cohort study with simulation.

    Science.gov (United States)

    Brändström, Helge; Sundelin, Anna; Hoseason, Daniela; Sundström, Nina; Birgander, Richard; Johansson, Göran; Winsö, Ola; Koskinen, Lars-Owe; Haney, Michael

    2017-05-12

    Post-craniotomy intracranial air can be present in patients scheduled for air ambulance transport to their home hospital. We aimed to assess risk for in-flight intracranial pressure (ICP) increases related to observed intracranial air volumes, hypothetical sea level pre-transport ICP, and different potential flight levels and cabin pressures. A cohort of consecutive subdural hematoma evacuation patients from one University Medical Centre was assessed with post-operative intracranial air volume measurements by computed tomography. Intracranial pressure changes related to estimated intracranial air volume effects of changing atmospheric pressure (simulating flight and cabin pressure changes up to 8000 ft) were simulated using an established model for intracranial pressure and volume relations. Approximately one third of the cohort had post-operative intracranial air. Of these, approximately one third had intracranial air volumes less than 11 ml. The simulation estimated that the expected changes in intracranial pressure during 'flight' would not result in intracranial hypertension. For intracranial air volumes above 11 ml, the simulation suggested that it was possible that intracranial hypertension could develop 'inflight' related to cabin pressure drop. Depending on the pre-flight intracranial pressure and air volume, this could occur quite early during the assent phase in the flight profile. DISCUSSION: These findings support the idea that there should be radiographic verification of the presence or absence of intracranial air after craniotomy for patients planned for long distance air transport. Very small amounts of air are clinically inconsequential. Otherwise, air transport with maintained ground-level cabin pressure should be a priority for these patients.

  20. A study on the air pollution related human diseases in Thiruvananthapuram City, Kerala

    Energy Technology Data Exchange (ETDEWEB)

    Bency, K.T.; Jansy, J.; Thakappan, B.; Kumar, B.; Sreelekha, T.T.; Hareendran, N.K.; Nair, P.K.K.; Krishnan Nair, M. [National Inst. of Environmental Health, Thiruvananthapuram, Kerala (India). Regional Cancer Centre

    2005-07-01

    This paper contains the results of a study that examined the impacts of air pollution on human health in Thiruvananthapuram City, India. The study compared health impacts arising from air pollution in three different zones including residential, commercial, and industrial. The paper presents the findings from the study according to each of these zones and presents conclusions.The study found that each zone had its individual environmental problems which were characterized by specific diseases. In the residential zone, there was a prevalence of diseases such as breast cancer and cardiac-related problems as well as dietary problems linked to obesity. In the industrial zone, respiratory illnesses related to air pollution were prevalent. Cardiac and vector-borne diseases, related to environmental hazards like waste water stagnation, dust and solid waste problem, were high in the commercial zone. 14 refs., 3 figs.

  1. Influence of the relative optical air mass on ultraviolet erythemal irradiance

    Science.gov (United States)

    Antón, M.; Serrano, A.; Cancillo, M. L.; García, J. A.

    2009-12-01

    The main objective of this article is to analyze the relationship between the transmissivity for ultraviolet erythemal irradiance (UVER) and the relative optical air mass at Badajoz (Southwestern Spain). Thus, a power expression between both variables is developed, which analyses in detail how atmospheric transmission is influenced by the total ozone column (TOC) and the atmospheric clearness. The period of analysis extends from 2001 to 2005. The experimental results indicate that clearness conditions play an important role in the relationship between UVER transmissivity and the relative optical air mass, while the effect of TOC is much smaller for this data set. In addition, the results show that UVER transmissivity is more sensitive to changes in atmospheric clearness than to TOC variability. Changes in TOC values higher than 15% cause UVER trasnmissivity to vary between 14% and 22%, while changes between cloud-free and overcast conditions produce variations in UVER transmissivity between 68% and 74% depending on the relative optical air mass.

  2. Ten-year mortality in a sample of an adult population in relation to air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Krzyzanowski, M; Wojtyniak, B

    1982-12-01

    The 10-year mortality in a sample of adult inhabitants of Cracow, Poland, was analysed according to the levels of air pollution in the area of residence. Smoking habit and several social and occupational factors were considered in the analysis, which was carried out with the use of a multivariate method for categorical variables. Among men the main effect of air pollution was marginally significant, but there was a significant interaction between air pollution and smoking. Among women no such relation could be detected. Also, the association between female mortality and smoking was not significant. From other factors considered in the analysis, only exposure at work to dust, high humidity, and variable temperature was related to mortality in both men and women. In addition among women higher mortality was related to a lower level of education.

  3. Modelling the relative stability of carbon nanotubes exposed to environmental adsorbates and air

    International Nuclear Information System (INIS)

    Barnard, Amanda S

    2009-01-01

    In parallel with the development of technological applications for carbon nanotubes, issues related to toxicology and environmental impact are also under increased scrutiny. It is clear from the available literature that the integrity of future carbon nanotube-based devices, our ability to anticipate failure of these devices, and our ability to manage the toxicological and environmental impacts require a detailed understanding of the stability of pure and functionalized carbon nanotubes under a full range of environmental conditions. Motivated by this endeavour, the present study uses a general thermodynamic model to predict the relative stability of carbon nanotubes exposed to a variety of atmospheric adsorbates, and uses them to examine the stability of nanotubes in air, as a function of the relative humidity. In general the results indicate that the adsorption of a sparse coverage of air is thermodynamically favoured, depending on the humidity, and the stability of small diameter nanotubes may be improved by exposure to humid air.

  4. Calculating the acidity of silanols and related oxyacids in aqueous solution

    Science.gov (United States)

    Tossell, John A.; Sahai, Nita

    2000-12-01

    can be correlated with underbondings or local electrostatic energies for the monomers, partially explaining the success of phenomenological models in correlating surface pK a of oxides with bond-strengths. Accurate evaluation of ΔH d, gas requires calculations with larger basis sets, inclusion of electron correlation effects, and corrections for vibrational, rotational, and translational contributions. Density functional and 2nd-order Moller-Plesset results for deprotonation enthalpies match well against higher-level G2(MP2) calculations. Direct calculation of solution pK a without resorting to correlations is presently impossible by ab initio methods because of inaccurate methods to account for solvation. Inclusion of explicit water molecules around the monomer immersed in a self-consistent reaction field (SCRF) provides the most accurate absolute hydration enthalpy (ΔH hyd) values, but IPCM values for the bare acid (HA) and anion (A -) give reasonable values of ΔH hyd, A - - ΔH hyd, HA values with much smaller computational expense. Polymers of silicate are used as model systems that begin to approach solid silica, known to be much more acidic than its monomer, Si(OH) 4. Polymerization of silicate or phosphate reduces their gas-phase ΔE d, gas relative to the monomers; differences in the electrostatic potential at H +, electronic relaxation and geometric relaxation energies all contribute to the effect. Internal H-bonding in the dimers results in unusually small ΔE d,gas which is partially counteracted by a reduced ΔH hyd. Accurate representation of hydration for oligomers persists as a fundamental problem in determining their solution pK a, because of the prohibitive cost involved in directly modeling interactions between many water molecules and the species of interest. Fortunately, though, the local contribution to the difference in hydration energy between the neutral polymeric acid and its anion seems to stabilize for a small number of explicit water

  5. Nasal congestion in relation to low air exchange rate in schools. Evaluation by acoustic rhinometry.

    Science.gov (United States)

    Wålinder, R; Norbäck, D; Wieslander, G; Smedje, G; Erwall, C

    1997-09-01

    Upper airway symptoms are common, but there is little information available on clinical findings in relation to indoor air pollution. This pilot study was conducted to test whether increased levels of indoor air pollutants in schools may correlate to a swelling of the nasal mucosa. The assumption was made that the degree of swelling could be related to the degree of decongestive effect of xylometazoline, and measured by acoustic rhinometry. The study was performed among 15 subjects in a school with low air exchange rate (0.6 air changes/h) and 12 subjects in a school with high air exchange rate (5.2 air changes/h). Hygienic measurements were performed in both schools. Acoustic rhinometry was performed for each individual under standardized forms. Cross-sectional areas and volumes of the nasal cavity were measured before and after decongestion with xylometazoline hydrochloride. Absolute values of the minimal cross-sectional area were lower in the school with poor ventilation. The decongestive effect of xylometazoline was significantly higher in the school with low air exchange, when correction for the influence of age was made. A diminished decongestive effect was seen with increasing age. The exposure measurements showed that indoor concentrations of volatile organic compounds, bacteria and moulds were higher in the school with low ventilation. In conclusion, raised levels of indoor air pollutants due to inadequate ventilation in schools may affect the upper airways and cause a swelling of the nasal mucosa, and acoustic rhinometry could be a useful objective method to measure human nasal reactions to the indoor environment.

  6. ESCLOUD: A computer program to calculate the air concentration, deposition rate and external dose rate from a continuous discharge of radioactive material to atmosphere

    International Nuclear Information System (INIS)

    Jones, J.A.

    1980-03-01

    Radioactive material may be discharged to atmosphere in small quantities during the normal operation of a nuclear installation as part of a considered waste management practice. Estimates of the individual and collective dose equivalent rates resulting from such a discharge are required in a number of contexts: for example, in assessing compliance with dose limits, in estimating the radiological impact of the discharge and as an input into optimisation studies. The suite of programs which has been developed to undertake such calculations is made up of a number of independent modules one of which, ESCLOUD, is described in this report. The ESCLOUD program evaluates, as a function of distance and direction from the release point, the air concentration, deposition rate and external β and γ doses from airborne and deposited activity. The air concentration and deposition rate can be used as input to other modules for calculating inhalation and ingestion doses. (author)

  7. 40 CFR 600.510-12 - Calculation of average fuel economy and average carbon-related exhaust emissions.

    Science.gov (United States)

    2010-07-01

    ... and average carbon-related exhaust emissions. 600.510-12 Section 600.510-12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY AND CARBON-RELATED EXHAUST EMISSIONS OF... Transportation. (iv) [Reserved] (2) Average carbon-related exhaust emissions will be calculated to the nearest...

  8. Application of the Monte Carlo method in calculation of energy-time distribution from a pulsed photon source in homogeneous air environment

    International Nuclear Information System (INIS)

    Ilic, R.D.; Vojvodic, V.I.; Orlic, M.P.

    1981-01-01

    The stochastic nature of photon interactions with matter and the characteristics of photon transport through real materials, are very well suited for applications of the Monte Carlo method in calculations of the energy-space distribution of photons. Starting from general principles of the Monte Carlo method, physical-mathematical model of photon transport from a pulsed source is given for the homogeneous air environment. Based on that model, a computer program is written which is applied in calculations of scattered photons delay spectra and changes of the photon energy spectrum. Obtained results provide the estimation of the timespace function of the electromagnetic field generated by photon from a pulsed source. (author)

  9. Thermal energy recovery of air conditioning system--heat recovery system calculation and phase change materials development

    International Nuclear Information System (INIS)

    Gu Zhaolin; Liu Hongjuan; Li Yun

    2004-01-01

    Latent heat thermal energy storage systems can be used to recover the rejected heat from air conditioning systems, which can be used to generate low-temperature hot water. It decreases not only the consumption of primary energy for heating domestic hot water but also the calefaction to the surroundings due to the rejection of heat from air conditioning systems. A recovery system using phase change materials (PCMs) to store the rejected (sensible and condensation) heat from air conditioning system has been developed and studied, making up the shortage of other sensible heat storage system. Also, PCMs compliant for heat recovery of air conditioning system should be developed. Technical grade paraffin wax has been discussed in this paper in order to develop a paraffin wax based PCM for the recovery of rejected heat from air conditioning systems. The thermal properties of technical grade paraffin wax and the mixtures of paraffin wax with lauric acid and with liquid paraffin (paraffin oil) are investigated and discussed, including volume expansion during the phase change process, the freezing point and the heat of fusion

  10. Air temperature and relative humidity in Dome Fuji Station buildings, East Antarctic ice sheet, in 2003

    Directory of Open Access Journals (Sweden)

    Takao Kameda

    2008-06-01

    Full Text Available In order to clarify the living condition in Dome Fuji Station in 2003, air temperature and relative humidity in the station were measured. Thermocouples with data logger and a ventilated psychrometer were used for the measurements. Average air temperature from February 11, 2003 to January 14, 2004 (missing period: July 19 to August 17 in the Dome Fuji Station buildings were as follows: Generator room 24.7℃, Dining room 23.5℃, Observation room 21.1℃, Dormitory room 18.2℃, Corridor 18.2℃, Food storage 8.2℃ and Old ice coring site -51.3℃. Average outside air temperature (1.5m height from the snow surface during the period was -54.4℃. A remarkable increase of outside air temperature (+30℃ at maximum due to a blocking high event was observed from October 31, 2003 to November 10, 2003 at Dome Fuji, during which increase of air temperature from 5 to 8°C in the station buildings was recorded. Snow on the station buildings was partly melted and some of the melted water penetrated into the station. This was the only time snow melted during the wintering over party's stay at the station. Average relative humidity in the station buildings obtained using a small humidifier was about 25%; the relative humidity without using the humidifier ranged from 9.0 to 22.9%.

  11. Pulmonary rehabilitation improves exercise capacity and dyspnea in air pollution-related respiratory disease.

    Science.gov (United States)

    Miyamoto, Naomi; Senjyu, Hideaki; Tanaka, Takako; Asai, Masaharu; Yanagita, Yorihide; Yano, Yudai; Nishinakagawa, Tsuyoshi; Kotaki, Kenji; Kitagawa, Chika; Rikitomi, Naoto; Kozu, Ryo; Honda, Sumihisa

    2014-01-01

    Air pollution in Japan caused respiratory disease, such as chronic bronchitis and asthma, in many individuals in the 1960s. Although air pollution has decreased, many victims of air pollution-related respiratory disease are limited in their activities of daily living because of respiratory symptoms. The purpose of this study was to evaluate the efficacy of pulmonary rehabilitation in victims of air pollution-related chronic bronchitis or asthma. Subjects were enrolled in a 12-week (2-week inpatient followed by 10-week outpatient) pulmonary rehabilitation program. The program comprised conditioning, strength training, endurance training, and patient education. We assessed the Modified Medical Research Council (MMRC) dyspnea grade, pulmonary function, peripheral muscle force, incremental shuttle walk distance (ISWD), and physical activity at baseline and immediately after the program. Twenty-nine subjects (mean age 74.2 ± 10.1 years, 11 males) completed the program, including 11 subjects with COPD and 18 subjects with asthma. Following rehabilitation, the participants (n = 29) showed significant improvements in MMRC dyspnea grade, vital capacity % predicted, quadriceps force and ISWD (all P pollution-related asthma. In conclusion, we recommend that patients with chronic bronchitis or asthma, resulting from exposure to air pollution, are referred for pulmonary rehabilitation.

  12. Neurobehavioral effects of exposure to traffic-related air pollution and transportation noise in primary schoolchildren.

    Science.gov (United States)

    van Kempen, Elise; Fischer, Paul; Janssen, Nicole; Houthuijs, Danny; van Kamp, Irene; Stansfeld, Stephen; Cassee, Flemming

    2012-05-01

    Children living close to roads are exposed to both traffic noise and traffic-related air pollution. There are indications that both exposures affect cognitive functioning. So far, the effects of both exposures have only been investigated separately. To investigate the relationship between air pollution and transportation noise on the cognitive performance of primary schoolchildren in both the home and school setting. Data acquired within RANCH from 553 children (aged 9-11 years) from 24 primary schools were analysed using multilevel modelling with adjustment for a range of socio-economic and life-style factors. Exposure to NO(2) (which is in urban areas an indicator for traffic-related air pollution) at school was statistically significantly associated with a decrease in the memory span length measured during DMST (χ(2)=6.8, df=1, p=0.01). This remained after additional adjustment for transportation noise. Statistically significant associations were observed between road and air traffic noise exposure at school and the number of errors made during the 'arrow' (χ(2)=7.5, df=1, p=0.006) and 'switch' (χ(2)=4.8, df=1, p=0.028) conditions of the SAT. This remained after adjustment for NO(2). No effects of air pollution exposure or transportation noise exposure at home were observed. Combined exposure of air pollution and road traffic noise had a significant effect on the reaction times measured during the SRTT and the 'block' and the 'arrow' conditions of the SAT. Our results provide some support that prolonged exposure to traffic-related air pollution as well as to noise adversely affects cognitive functioning. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. System calculations related to the accident at Three-Mile Island using TRAC

    International Nuclear Information System (INIS)

    Ireland, J.R.

    1980-01-01

    The Three Mile Island nuclear plant (Unit 2) was modeled using the Transient Reactor Analysis Code (TRAC-P1A) and a base case calculation, which simulated the initial part of the accident that occurred on March 28, 1979, was performed. In addition to the base case calculation, several parametric calculations were performed in which a single hypothetical change was made in the system conditions, such as assuming the high pressure injection (HPI) system operated as designed rather than as in the accident. Some of the important system parameter comparisons for the base case as well as some of the parametric case results are presented

  14. Ambient air pollution exposure and the incidence of related health effects among racial/ethnic minorities

    Energy Technology Data Exchange (ETDEWEB)

    Nieves, L.A.; Wernette, D.R.

    1997-02-01

    Differences among racial and ethnic groups in morbidity and mortality rates for diseases, including diseases with environmental causes, have been extensively documented. However, documenting the linkages between environmental contaminants, individual exposures, and disease incidence has been hindered by difficulties in measuring exposure for the population in general and for minority populations in particular. After briefly discussing research findings on associations of common air pollutants with disease incidence, the authors summarize recent studies of radial/ethnic subgroup differences in incidence of these diseases in the US. They then present evidence of both historic and current patterns of disproportionate minority group exposure to air pollution as measured by residence in areas where ambient air quality standards are violated. The current indications of disproportionate potential exposures of minority and low-income populations to air pollutants represent the continuation of a historical trend. The evidence of linkage between disproportionate exposure to air pollution of racial/ethnic minorities and low-income groups and their higher rates of some air pollution-related diseases is largely circumstantial. Differences in disease incidence and mortality rates among racial/ethnic groups are discussed for respiratory diseases, cancers, and lead poisoning. Pollutants of concern include CO, Pb, SO{sub 2}, O{sub 3}, and particulates.

  15. Air pollution exposure in Oslo, Drammen, Bergen and Trondheim. Calculations of NO2, PM10 and PM2,5 for the winter 1995 to 1996

    International Nuclear Information System (INIS)

    Sloerdal, Leif Haavard

    1998-07-01

    The Norwegian Institute for Air Research (NILU) commissioned by the Norwegian Pollution Control Authority (Statens forurensningstilsyn), has calculated human exposure values to NO 2 , PM 1 0 and PM 2 ,5 in the cities of Oslo, Drammen, Bergen and Trondheim. In Oslo, Drammen and Bergen the calculations are made for the winter 1995 to 1996. For Trondheim the necessary meteorological data were missing and the calculations are therefore made for the winter of 1994 to 1995. In the project only simplified exposure calculations are carried out where estimated ground concentrations and population distribution information at the km 2 level are connected. The calculations are then made as if everyone have been outside at the home address during the entire estimation period, termed ''potential exposure''. The population exposure load is estimated for excesses of various air quality criteria and the results are presented. In addition values for the worst hour and/or the worst day of exposure for each of the four cities are presented. The term worst is defined as the hour or the day in the simulation period where the most number of people are exposed to concentrations exceeding the threshold values for air quality recommended by the Norwegian Pollution Control Authority. For NO 2 these threshold figures are 100 microgram/m 3 for hour values and 75 microgram/m 3 for day values. For PM 1 0 and PM 2 ,5 criteria for hour values do not exist while day values are now stipulated as 35 microgram/m 3 for PM 1 0 and 20 microgram/m 3 for PM 2 ,5. The calculated maximum concentrations may not coincide with these values. The report gives results for exposure estimates for NO 2 , PM 1 0 and PM 2 ,5 in the cities and evaluates the significance of regional background levels, traffic and heating emissions in contributions to the total population exposure load. The exposure to NO 2 is largest in Bergen. The PM 1 0 and PM 2 ,5 i.e. particle exposure, is greater than for NO 2 and is largest in Oslo

  16. The relation between air pollution and respiratory deaths in Tehran, Iran- using generalized additive models.

    Science.gov (United States)

    Dehghan, Azizallah; Khanjani, Narges; Bahrampour, Abbas; Goudarzi, Gholamreza; Yunesian, Masoud

    2018-03-20

    Some epidemiological evidence has shown a relation between ambient air pollution and adverse health outcomes. The aim of this study was to investigate the effect of air pollution on mortality from respiratory diseases in Tehran, Iran. In this ecological study, air pollution data was inquired from the Tehran Province Environmental Protection Agency and the Tehran Air Quality Control Company. Meteorological data was collected from the Tehran Meteorology Organization and mortality data from the Tehran Cemetery Mortality Registration. Generalized Additive Models (GAM) was used for data analysis with different lags, up to 15 days. A 10-unit increase in all pollutants except CO (1-unit) was used to compute the Relative Risk of deaths. During 2005 until 2014, 37,967 respiratory deaths occurred in Tehran in which 21,913 (57.7%) were male. The strongest relationship between NO 2 and PM 10 and respiratory death was seen on the same day (lag 0), and was respectively (RR = 1.04, 95% CI: 1.02-1.07) and (RR = 1.03, 95% CI: 1.02-1.04). O 3 and PM 2.5 had the strongest relationship with respiratory deaths on lag 2 and 1 respectively, and the RR was equal to 1.03, 95% CI: 1.01-1.05 and 1.06, 95% CI: 1.02-1.10 respectively. NO 2 , O 3 , PM 10 and PM 2.5 also showed significant relations with respiratory deaths in the older age groups. The findings of this study showed that O 3 , NO 2 , PM 10 and PM 2.5 air pollutants were related to respiratory deaths in Tehran. Reducing ambient air pollution can save lives in Tehran.

  17. Elevated air movement enhances stomatal sensitivity to abscisic acid in leaves developed at high relative air humidity

    Directory of Open Access Journals (Sweden)

    Dália R.A. Carvalho

    2015-05-01

    Full Text Available High relative air humidity (RH ≥ 85% during growth leads to stomata malfunctioning, resulting in water stress when plants are transferred to conditions of high evaporative demand. In this study, we hypothesized that an elevated air movement (MOV 24 h per day, during the whole period of leaf development would increase abscisic acid concentration ([ABA] enhancing stomatal functioning. Pot rose ‘Toril’ was grown at moderate (61% or high (92% RH combined with a negligible MOV or with a continuous MOV of 0.92 m s-1. High MOV reduced stomatal pore length and aperture in plants developed at high RH. Moreover, stomatal function improved when high MOV-treated plants were subjected to leaflet desiccation and ABA feeding. Endogenous concentration of ABA and its metabolites in the leaves was reduced by 35% in high RH, but contrary to our hypothesis this concentration was not significantly affected by high MOV. Interestingly, in detached leaflets grown at high RH, high MOV increased stomatal sensitivity to ABA since the amount of exogenous ABA required to decrease the transpiration rate was significantly reduced. This is the first study to show that high MOV increases stomatal functionality in leaves developed at high RH by reducing the stomatal pore length and aperture and enhancing stomatal sensitivity to ABA rather than increasing leaf [ABA].

  18. Calculations on displacement damage and its related parameters for heavy ion bombardment in reactor materials

    International Nuclear Information System (INIS)

    Sone, Kazuho; Shiraishi, Kensuke

    1975-04-01

    The depth distribution of displacement damage expressed in displacements per atom (DPA) in reactor materials such as Mo, Nb, V, Fe and Ni bombarded by energetic nitrogen, argon and self ions with incident energy below 2 MeV was calculated following the theory developed by Lindhard and co-workers for the partition of energy as an energetic ion slowing down. In this calculation, energy loss due to electron excitation was taken into account for the atomic collision cascade after the primary knock-on process. Some parameters indispensable for the calculation such as energy loss rate, damage efficiency, projected range and its straggling were tabulated as a function of incident ion energy of 20 keV to 2 MeV. The damage and parameters were also calculated for 2 MeV nickel ions bombarding Fe targets. In this case, the DPA value is of 40--75% overestimated in a calculation disregarding electronic energy loss for primary knock-on atoms. The formula proposed in this report is significant for calculations on displacement damage produced by heavy ion bombardment as a simulation of high fluence fast neutron damage. (auth.)

  19. Calculations on displacement damage and its related parameters for heavy ion bombardment in reactor materials

    Energy Technology Data Exchange (ETDEWEB)

    Sone, K; Shiraishi, K

    1975-04-01

    The depth distribution of displacement damage expressed in displacements per atom (DPA) in reactor materials such as Mo, Nb, V, Fe and Ni bombarded by energetic nitrogen, argon and self ions with incident energy below 2 MeV was calculated following the theory developed by Lindhard and co-workers for the partition of energy as an energetic ion slowing down. In this calculation, energy loss due to electron excitation was taken into account for the atomic collision cascade after the primary knock-on process. Some parameters indispensable for the calculation such as energy loss rate, damage efficiency, projected range and its straggling were tabulated as a function of incident ion energy of 20 keV to 2 MeV. The damage and parameters were also calculated for 2 MeV nickel ions bombarding Fe targets. In this case, the DPA value is of 40--75% overestimated in a calculation disregarding electronic energy loss for primary knock-on atoms. The formula proposed in this report is significant for calculations on displacement damage produced by heavy ion bombardment as a simulation of high fluence fast neutron damage.

  20. The effect of flight-related behaviour on the risk of venous thrombosis after air travel

    NARCIS (Netherlands)

    Schreijer, Anja J.M.; Cannegieter, Suzanne C.; Doggen, Catharina Jacoba Maria; Rosendaal, Frits R.

    2009-01-01

    In a case–control study including 11 033 participants (The Multiple Environmental and Genetic Assessment of risk factors for venous thrombosis study) on risk factors of venous thrombosis, we studied the effect of flight-related behaviour on the risk of venous thrombosis after air travel. Patients

  1. High accuracy acoustic relative humidity measurement in duct flow with air

    NARCIS (Netherlands)

    Schaik, van W.; Grooten, M.H.M.; Wernaart, T.; Geld, van der C.W.M.

    2010-01-01

    An acoustic relative humidity sensor for air-steam mixtures in duct flow is designed and tested. Theory, construction, calibration, considerations on dynamic response and results are presented. The measurement device is capable of measuring line averaged values of gas velocity, temperature and

  2. 75 FR 66125 - Federal Land Managers' Air Quality Related Values Work Group (FLAG)

    Science.gov (United States)

    2010-10-27

    ... pollutants that could affect the health and status of resources in areas managed by the three agencies... Work Group (FLAG) AGENCY: National Park Service, Interior. ACTION: Notice of availability of final... Public Comments document. The Federal Land Managers' Air Quality Related Values Work Group (FLAG) was...

  3. Disease burden due to biomass cooking-fuel-related household air pollution among women in India.

    Science.gov (United States)

    Sehgal, Meena; Rizwan, Suliankatchi Abdulkader; Krishnan, Anand

    2014-01-01

    Household air pollution (HAP) due to biomass cooking fuel use is an important risk factor for a range of diseases, especially among adult women who are primary cooks, in India. About 80% of rural households in India use biomass fuel for cooking. The aim of this study is to estimate the attributable cases (AC) for four major diseases/conditions associated with biomass cooking fuel use among adult Indian women. We used the population attributable fraction (PAF) method to calculate the AC of chronic bronchitis, tuberculosis (TB), cataract, and stillbirths due to exposure to biomass cooking fuel. A number of data sources were accessed to obtain population totals and disease prevalence rates. A meta-analysis was conducted to obtain adjusted pooled odds ratios (ORs) for strength of association. Using this, PAF and AC were calculated using a standard formula. Results were presented as number of AC and 95% confidence intervals (CI). The fixed effects pooled OR obtained from the meta-analysis were 2.37 (95% CI: 1.59, 3.54) for chronic bronchitis, 2.33 (1.65, 3.28) for TB, 2.16 (1.42, 3.26) for cataract, and 1.26 (1.12, 1.43) for stillbirths. PAF varied across conditions being maximum (53%) for chronic bronchitis in rural areas and least (1%) for cataract in older age and urban areas. About 2.4 (95% CI: 1.4, 3.1) of 5.6 m cases of chronic bronchitis, 0.3 (0.2, 0.4) of 0.76 m cases of TB, 5.0 (2.8, 6.7) of 51.4 m cases of cataract among adult Indian women and 0.02 (0.01, 0.03) of 0.15 m stillbirths across India are attributable to HAP due to biomass cooking fuel. These estimates should be cautiously interpreted in the light of limitations discussed which relate to exposure assessment, exposure characterization, and age-specific prevalence of disease. HAP due to biomass fuel has diverse and major impacts on women's health in India. Although challenging, incorporating the agenda of universal clean fuel access or cleaner technology within the broader framework of rural

  4. 76 FR 22665 - Release of Final Document Related to the Review of the National Ambient Air Quality Standards for...

    Science.gov (United States)

    2011-04-22

    ... criteria. The revised air quality criteria reflect advances in scientific knowledge on the effects of the... National Ambient Air Quality Standards, contains staff analyses of the scientific bases for alternative... Document Related to the Review of the National Ambient Air Quality Standards for Particulate Matter AGENCY...

  5. Traffic-related air pollution, preterm birth and term birth weight in the PIAMA birth cohort study

    NARCIS (Netherlands)

    Gehring, Ulrike; Wijga, Alet H.; Fischer, Paul; de Jongste, Johan C.; Kerkhof, Marjan; Koppelman, Gerard H.; Smit, Henriette A.; Brunekreef, Bert

    Background: Maternal exposure to air pollution has been associated with adverse pregnancy outcomes. Few studies took into account the spatial and temporal variation of air pollution levels. Objectives: To evaluate the impact of maternal exposure to traffic-related air pollution during pregnancy on

  6. Correction factors for the NMi free-air ionization chamber for medium-energy x-rays calculated with the Monte Carlo method

    International Nuclear Information System (INIS)

    Grimbergen, T.W.M.; Dijk, E. van; Vries, W. de

    1998-01-01

    A new method is described for the determination of x-ray quality dependent correction factors for free-air ionization chambers. The method is based on weighting correction factors for mono-energetic photons, which are calculated using the Monte Carlo method, with measured air kerma spectra. With this method, correction factors for electron loss, scatter inside the chamber and transmission through the diaphragm and front wall have been calculated for the NMi free-air chamber for medium-energy x-rays for a wide range of x-ray qualities in use at NMi. The newly obtained correction factors were compared with the values in use at present, which are based on interpolation of experimental data for a specific set of x-ray qualities. For x-ray qualities which are similar to this specific set, the agreement between the correction factors determined with the new method and those based on the experimental data is better than 0.1%, except for heavily filtered x-rays generated at 250 kV. For x-ray qualities dissimilar to the specific set, differences up to 0.4% exist, which can be explained by uncertainties in the interpolation procedure of the experimental data. Since the new method does not depend on experimental data for a specific set of x-ray qualities, the new method allows for a more flexible use of the free-air chamber as a primary standard for air kerma for any x-ray quality in the medium-energy x-ray range. (author)

  7. Calculated Phase Relations in the System KFMASH Between 6 and 16 GPa

    Science.gov (United States)

    Massonne, H.; Brandelik, A.

    2005-12-01

    To better understand the modal compositions of deeply buried metagranitoids and metapelites, phase relations in the model system K2O-FeO-MgO-Al2O3-SiO2-H2O (KFMASH) with SiO2 in excess were calculated applying thermodynamic principles. We used the software package PTGIBBS, published data, and thermodynamic data (e.g. for phase egg (AlSiO3OH), K-hollandite (KAlSi3O8)) newly derived on the basis of former high-pressure (HP) experiments. Non-ideal mixing was considered for the solid solution series of garnet (components: pyrope, majorite, almandine) and potassic white mica (components: muscovite, MgAl-celadonite, FeAl-celadonite). For phases such as HP-clinoenstatite ((Mg,Fe)SiO3), Si-spinel ((Fe,Mg)2SiO4), and beta phase ((Mg,Fe)2SiO4) only binary solid solutions, assuming ideal mixing, were taken into account. On the basis of the above data, we constructed petrogenetic grids mainly for the P-T range 6 to 16 GPa and 600 to 1600 ° C. Typical features of these grids are, for instance, the disappearance of K-cymrite (KAlSi3O8 H2O) with rising pressure close to 10 GPa and the occurrence of phase egg above 12 GPa. In KMASH potassic white mica reacts with OH-topaz at about 11 GPa (1000-1200 ° C) to form pyrope + K-hollandite. The content of majorite component in pyrope is less than 1 mol% which is systematically so for all garnets coexisting with an Al-silicate at least up to 16 GPa. Potassic white mica, which is virtually pure MgAl-celadonite, finally breaks down at pressures close to 12 GPa. Decomposition assemblages are K-hollandite + HP-clinoenstatite + H2O (T free) garnet + Al-silicate. The latter phase is either OH-topaz (Al2SiO4(OH)2) or phase egg or kyanite also depending on the availability of H2O. Metagranitoids should be composed of shishovite + K-hollandite + majorite-bearing garnet + (enstatite-rich) clinopyroxene. Si-spinel is an important additional phase in this assemblage. This phase shows increasing amounts by approaching to 16 GPa.

  8. Development of project management data calculation models relating to dismantling of nuclear facilities. Contract research

    Energy Technology Data Exchange (ETDEWEB)

    Sukegawa, Takenori; Ohshima, Soichiro; Shiraishi, Kunio; Yanagihara, Satoshi [Department of Decommissioning and Waste Management, Tokai Research Establishment, Japan Atomic Energy Research Institute, Tokai Ibaraki (Japan)

    1999-02-01

    Labor-hours necessary for dismantling activities are generally estimated based on experience, for example, as a form of unit productivity factors such as the relationship between labor-hours and weight of components dismantled which were obtained by actual dismantling activities. The project management data calculation models together with unit productivity factors for basic dismantling work activities were developed by analyzing the data obtained from the Japan Power Demonstration Reactor (JPDR) dismantling project, which will be applicable to estimation of labor-hours in various dismantling conditions. Typical work breakdown structures were also prepared by categorizing repeatable basic dismantling work activities for effective planning of dismantling activities. The labor-hours for dismantling the JPDR components and structures were calculated by using the code system for management of reactor decommissioning (COSMARD), in which the work breakdown structures and the calculation models were contained. It was confirmed that the labor-hours could be easily estimated by COSMARD through the calculations. This report describes the labor-hour calculation models and application of these models to COSMARD. (author)

  9. Relational Reasoning about Numbers and Operations--Foundation for Calculation Strategy Use in Multi-Digit Multiplication and Division

    Science.gov (United States)

    Schulz, Andreas

    2018-01-01

    Theoretical analysis of whole number-based calculation strategies and digit-based algorithms for multi-digit multiplication and division reveals that strategy use includes two kinds of reasoning: reasoning about the relations between numbers and reasoning about the relations between operations. In contrast, algorithms aim to reduce the necessary…

  10. Microbial air quality in mass transport buses and work-related illness among bus drivers of Bangkok Mass Transit Authority.

    Science.gov (United States)

    Luksamijarulkul, Pipat; Sundhiyodhin, Viboonsri; Luksamijarulkul, Soavalug; Kaewboonchoo, Orawan

    2004-06-01

    The air quality in mass transport buses, especially air-conditioned buses may affect bus drivers who work full time. Bus numbers 16, 63, 67 and 166 of the Seventh Bus Zone of Bangkok Mass Transit Authority were randomly selected to investigate for microbial air quality. Nine air-conditioned buses and 2-4 open-air buses for each number of the bus (36 air-conditioned buses and 12 open-air buses) were included. Five points of in-bus air samples in each studied bus were collected by using the Millipore A ir Tester Totally, 180 and 60 air samples collected from air-conditioned buses and open-air buses were cultured for bacterial and fungal counts. The bus drivers who drove the studied buses were interviewed towards histories of work-related illness while working. The results revealed that the mean +/- SD of bacterial counts in the studied open-air buses ranged from 358.50 +/- 146.66 CFU/m3 to 506 +/- 137.62 CFU/m3; bus number 16 had the highest level. As well as the mean +/- SD of fungal counts which ranged from 93.33 +/- 44.83 CFU/m3 to 302 +/- 294.65 CFU/m3; bus number 166 had the highest level. Whereas, the mean +/- SD of bacterial counts in the studied air-conditioned buses ranged from 115.24 +/- 136.01 CFU/m3 to 244.69 +/- 234.85 CFU/m3; bus numbers 16 and 67 had the highest level. As well as the mean +/- SD of fungal counts which rangedfrom 18.84 +/- 39.42 CFU/m3 to 96.13 +/- 234.76 CFU/m3; bus number 166 had the highest level. When 180 and 60 studied air samples were analyzed in detail, it was found that 33.33% of the air samples from open-air buses and 6.11% of air samples from air-conditioned buses had a high level of bacterial counts (> 500 CFU/m3) while 6.67% of air samples from open-air buses and 2.78% of air samples from air-conditioned buses had a high level of fungal counts (> 500 CFU/m3). Data from the history of work-related illnesses among the studied bus drivers showed that 91.67% of open-air bus drivers and 57.28% of air-conditioned bus drivers had

  11. Locally derived traffic-related air pollution and fetal growth restriction: a retrospective cohort study.

    Science.gov (United States)

    Pereira, Gavin; Cook, Angus G; Haggar, Fatima; Bower, Carol; Nassar, Natasha

    2012-11-01

    Fetal growth restriction has been inconsistently associated with maternal exposure to elevated levels of traffic-related air pollution. We investigated the relationship between an individualised measure of fetal growth and maternal exposure to a specific marker for traffic-related air pollution. We estimated maternal residential exposure to a marker for traffic-related air pollution (nitrogen dioxide, NO2) during pregnancy for 23,452 births using temporally adjusted land-use regression. Logistic regression was used to investigate associations with small for gestational age and sex (SGA) and fetal growth restriction, defined as proportion of optimal birth weight (POBW) below the 10th percentile. Sub-populations investigated were: women who spent most time at home, women who did not move house, women with respiratory or circulatory morbidity, women living in low/middle/high socio-economic areas, women who delivered before 37 weeks gestation, and women who delivered from 37 weeks gestation. An IQR increase in traffic-related air pollution in the second trimester across all women was associated with an OR of 1.31 (95% CI 1.07 to 1.60) for fetal growth restriction. Effects on fetal growth restriction (low POBW) were highest among women who subsequently delivered before 37 weeks of gestation. Effects on SGA were highest among women who did not move house: OR 1.35 (95% CI 1.08 to 1.69). Larger effect sizes were observed for low POBW than for SGA. Exposure to traffic-related air pollution in mid to late pregnancy was associated with risk of SGA and low POBW in this study.

  12. Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, Daniel I. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2010-03-15

    The Savannah River Site disposes of low-activity radioactive waste within subsurface-engineered facilities. One of the tools used to establish the capacity of a given site to safely store radioactive waste (i.e., that a site does not exceed its Waste Acceptance Criteria) is the Performance Assessment (PA). The objective of this document is to provide the geochemical values for the PA calculations. This work is being conducted as part of the on-going maintenance program that permits the PA to periodically update existing calculations when new data become available.

  13. Energy-depth relation of electrons in bulk targets by Monte-Carlo calculations

    International Nuclear Information System (INIS)

    Gaber, M.; Fitting, H.J.

    1984-01-01

    Monte-Carlo calculations are used to calculate the energy of penetrating electrons as a function of the depth in thick targets of Ti, Fe, Cu, As, In, and Au. It is shown that the mean energy ratio anti E(z)/E 0 decays exponentially with depth z and depends on the backscattering coefficient eta/sub B/ of the bulk material and the maximum range R(E 0 ) of the primary electrons with initial energy E 0 . Thereby a normalized plot anti E/E 0 as a function of the reduced depth z/R becomes possible. (author)

  14. Calculation of the phonon density of states and related thermodynamic properties for trigonal selenium

    DEFF Research Database (Denmark)

    Hansen, Flemming Yssing; Alldredge, G. P.; McMurry, H. L.

    1983-01-01

    The phonon density of states for trigonal selenium has been calculated on the basis of a short range force model giving good overall agreement with experimental room temperature phonon dispersion data. A qualitative comparison with an experimental determination of the phonon density of states shows...... similarities in the gross features, but the experimental data lacks many of the finer details shown by the theoretical results due to resolution effects. The lattice dynamical contribution to the heat capacity CV is calculated and is found to be in good agreement with experimental determinations of Cp after...

  15. Electronic, vibrational and related properties of group IV metal oxides by ab initio calculations

    International Nuclear Information System (INIS)

    Leite Alves, H.W.; Silva, C.C.; Lino, A.T.; Borges, P.D.; Scolfaro, L.M.R.; Silva, E.F. da

    2008-01-01

    We present our theoretical results for the structural, electronic, vibrational and optical properties of MO 2 (M = Sn, Zr, Hf and Ti) obtained by first-principles calculations. Relativistic effects are demonstrated to be important for a realistic description of the detailed structure of the electronic frequency-dependent dielectric function, as well as of the carrier effective masses. Based on our results, we found that the main contribution of the high values calculated for the oxides dielectric constants arises from the vibrational properties of these oxides, and the vibrational static dielectric constant values diminish with increasing pressure

  16. Model calculations of the effects of present and future emissions of air pollutants from shipping in the Baltic Sea and the North Sea

    Directory of Open Access Journals (Sweden)

    J. E. Jonson

    2015-01-01

    Full Text Available Land-based emissions of air pollutants in Europe have steadily decreased over the past two decades, and this decrease is expected to continue. Within the same time span emissions from shipping have increased in EU ports and in the Baltic Sea and the North Sea, defined as SECAs (sulfur emission control areas, although recently sulfur emissions, and subsequently particle emissions, have decreased. The maximum allowed sulfur content in marine fuels in EU ports is now 0.1%, as required by the European Union sulfur directive. In the SECAs the maximum fuel content of sulfur is currently 1% (the global average is about 2.4%. This will be reduced to 0.1% from 2015, following the new International Maritime Organization (IMO rules. In order to assess the effects of ship emissions in and around the Baltic Sea and the North Sea, regional model calculations with the EMEP air pollution model have been made on a 1/4° longitude × 1/8° latitude resolution, using ship emissions in the Baltic Sea and the North Sea that are based on accurate ship positioning data. The effects on depositions and air pollution and the resulting number of years of life lost (YOLLs have been calculated by comparing model calculations with and without ship emissions in the two sea areas. In 2010 stricter regulations for sulfur emissions were implemented in the two sea areas, reducing the maximum sulfur content allowed in marine fuels from 1.5 to 1%. In addition ships were required to use fuels with 0.1 % sulfur in EU harbours. The calculations have been made with emissions representative of 2009 and 2011, i.e. before and after the implementation of the stricter controls on sulfur emissions from 2010. The calculations with present emissions show that per person, an additional 0.1–0.2 years of life lost is estimated in areas close to the major ship tracks with current emission levels. Comparisons of model calculations with emissions before and after the implementation of stricter

  17. Effects of bone- and air-tissue inhomogeneities on the dose distributions of the Leksell Gamma Knife (registered) calculated with PENELOPE

    International Nuclear Information System (INIS)

    Al-Dweri, Feras M O; Rojas, E Leticia; Lallena, Antonio M

    2005-01-01

    Monte Carlo simulation with PENELOPE (version 2003) is applied to calculate Leksell Gamma Knife (registered) dose distributions for heterogeneous phantoms. The usual spherical water phantom is modified with a spherical bone shell simulating the skull and an air-filled cube simulating the frontal or maxillary sinuses. Different simulations of the 201 source configuration of the Gamma Knife have been carried out with a simplified model of the geometry of the source channel of the Gamma Knife recently tested for both single source and multisource configurations. The dose distributions determined for heterogeneous phantoms including the bone- and/or air-tissue interfaces show non-negligible differences with respect to those calculated for a homogeneous one, mainly when the Gamma Knife isocentre approaches the separation surfaces. Our findings confirm an important underdosage (∼10%) nearby the air-tissue interface, in accordance with previous results obtained with the PENELOPE code with a procedure different from ours. On the other hand, the presence of the spherical shell simulating the skull produces a few per cent underdosage at the isocentre wherever it is situated

  18. Home outdoor models for traffic-related air pollutants do not represent personal exposure measurements in Southern California

    International Nuclear Information System (INIS)

    Ducret-Stich, R; Gemperli, A; Ineichen, A; Phuleria, H C; Delfino, R J; Tjoa, T; Wu, J; Liu, L-J S

    2009-01-01

    Recent studies have used measurements or estimates of traffic-related air pollutants at home or school locations to link associations between exposure and health. However, little is known about the validity of these outdoor concentrations as an estimate for personal exposure to traffic. This paper compares modelled outdoor concentrations at home with personal exposure to traffic air pollution of 63 children in two areas in Los Angeles in 2003/2004. Exposure monitoring consisted of sixteen 10-day monitoring runs, with each run monitoring 4 subjects concurrently with the active personal DataRAM for particulate matter 25 ), elemental carbon (EC) and organic carbon (OC). One child per run had concurrent indoor/outdoor home monitoring. Measurements at central sites (24-hr PM 25 , EC, OC) were taken daily and concentrations of PM 25 , EC, and OC from traffic sources were calculated using the CALINE4 model for individual residences. We modelled outdoor concentrations of PM 2 5 , EC and OC with multilinear regression including GIS and meteorological parameters and adjusted for auto-correlation between repeated measurements. The model fit (R 2 ) for home outdoor estimates was 0.94, 0.74 and 0.80 for PM 25 , EC and OC, respectively. Comparisons between these outdoor estimates and the personal measurements showed a good agreement for PM 25 (R 2 =0.65-0.70) with a mean bias of -0.7±11.8|ag for the smog receptor area, and 18.9±16.2|ag for the traffic impacted area. However the outdoor estimates were not related to personal exposure for EC (R 2 =0.01-0.29) and OC (R 2 =0.03- 0.14). Conclusions: Predictions of outdoor concentrations can be used as approximations of personal exposure to PM 25 . However, they are not appropriate for estimating personal exposure to traffic-related air pollutants including EC and OC in studies of acute exposure-response relationships.

  19. Good practices in managing work-related indoor air problems: a psychosocial perspective.

    Science.gov (United States)

    Lahtinen, Marjaana; Huuhtanen, Pekka; Vähämäki, Kari; Kähkönen, Erkki; Mussalo-Rauhamaa, Helena; Reijula, Kari

    2004-07-01

    Indoor air problems at workplaces are often exceedingly complex. Technical questions are interrelated with the dynamics of the work community, and the cooperation and interaction skills of the parties involved in the problem solving process are also put to the test. The objective of our study was to analyze the process of managing and solving indoor air problems from a psychosocial perspective. This collective case study was based on data from questionnaires, interviews and various documentary materials. Technical inspections of the buildings and indoor air measurements were also carried out. The following four factors best differentiated successful cases from impeded cases: extensive multiprofessional collaboration and participative action, systematic action and perseverance, investment in information and communication, and process thinking and learning. The study also proposed a theoretical model for the role of the psychosocial work environment in indoor air problems. The expertise related to social and human aspects of problem solving plays a significant role in solving indoor air problems. Failures to properly handle these aspects may lead to resources being wasted and result in a problematic situation becoming stagnant or worse. Copyright 2004 Wiley-Liss, Inc.

  20. Residential exposure to traffic-related air pollution and survival after heart failure.

    Science.gov (United States)

    Medina-Ramón, Mercedes; Goldberg, Robert; Melly, Steven; Mittleman, Murray A; Schwartz, Joel

    2008-04-01

    Although patients with heart failure (HF) have been identified as particularly susceptible to the acute effects of air pollution, the effects of long-term exposure to air pollution on patients with this increasingly prevalent disease are largely unknown. This study was designed to examine the mortality risk associated with residential exposure to traffic-related air pollution among HF patients. A total of 1,389 patients hospitalized with acute HF in greater Worcester, Massachusetts, during 2000 were followed for survival through December 2005. We used daily traffic within 100 and 300 m of residence as well as the distance from residence to major roadways and to bus routes as proxies for residential exposure to traffic-related air pollution. We assessed mortality risks for each exposure variable using Cox proportional hazards models adjusted for prognostic factors. After the 5-year follow-up, only 334 (24%) subjects were still alive. An interquartile range increase in daily traffic within 100 m of home was associated with a mortality hazard ratio (HR) of 1.15 [95% confidence interval (CI), 1.05-1.25], whereas for traffic within 300 m this association was 1.09 (95% CI, 1.01-1.19). The mortality risk decreased with increasing distance to bus routes (HR = 0.88; 95% CI, 0.81-0.96) and was larger for those living within 100 m of a major roadway or 50 m of a bus route (HR = 1.30; 95% CI, 1.13-1.49). Adjustment for area-based income and educational level slightly attenuated these associations. Residential exposure to traffic-related air pollution increases the mortality risk after hospitalization with acute HF. Reducing exposure to traffic-related emissions may improve the long-term prognosis of HF patients.

  1. Mathematics Anxiety and Mathematics Self-Efficacy in Relation to Medication Calculation Performance in Nurses

    Science.gov (United States)

    Melius, Joyce

    2012-01-01

    The purpose of this study is to identify and analyze the relationships that exist between mathematics anxiety and nurse self-efficacy for mathematics, and the medication calculation performance of acute care nurses. This research used a quantitative correlational research design and involved a sample of 84 acute care nurses, LVNs and RNs, from a…

  2. Hydraulic Calculations Relating to the Flooding and Draining of the Roman Colosseum for Naumachiae

    OpenAIRE

    Crapper, Martin

    2007-01-01

    This report includes full details of the calculations used in determining flows into and out of the Colosseum. It should be read in conjunction with the published paper in the Proceedings of ICE Civil Engineering 160 November 2007 Pages 184–191 Paper 900019.

  3. First and second chance fission calculations for actinides and related topics

    International Nuclear Information System (INIS)

    Maino, G.; Menapace, E.; Motta, M.; Ventura, A.

    1980-01-01

    First and second chance contributions to neutron induced fission cross sections in an energy range of interest for reactor applications (E/sub n/less than or equal to 13 MeV) were obtained by extensive and consistent calculations for 241 Am; moreover, a simplified semiempirical approach was applied to 235 U and 239 Pu

  4. Aircraft engine exhaust emissions and other airport-related contributions to ambient air pollution: A review

    Science.gov (United States)

    Masiol, Mauro; Harrison, Roy M.

    2014-10-01

    Civil aviation is fast-growing (about +5% every year), mainly driven by the developing economies and globalisation. Its impact on the environment is heavily debated, particularly in relation to climate forcing attributed to emissions at cruising altitudes and the noise and the deterioration of air quality at ground-level due to airport operations. This latter environmental issue is of particular interest to the scientific community and policymakers, especially in relation to the breach of limit and target values for many air pollutants, mainly nitrogen oxides and particulate matter, near the busiest airports and the resulting consequences for public health. Despite the increased attention given to aircraft emissions at ground-level and air pollution in the vicinity of airports, many research gaps remain. Sources relevant to air quality include not only engine exhaust and non-exhaust emissions from aircraft, but also emissions from the units providing power to the aircraft on the ground, the traffic due to the airport ground service, maintenance work, heating facilities, fugitive vapours from refuelling operations, kitchens and restaurants for passengers and operators, intermodal transportation systems, and road traffic for transporting people and goods in and out to the airport. Many of these sources have received inadequate attention, despite their high potential for impact on air quality. This review aims to summarise the state-of-the-art research on aircraft and airport emissions and attempts to synthesise the results of studies that have addressed this issue. It also aims to describe the key characteristics of pollution, the impacts upon global and local air quality and to address the future potential of research by highlighting research needs.

  5. Traffic-related air pollution exposure and incidence of stroke in four cohorts from Stockholm.

    Science.gov (United States)

    Korek, Michal J; Bellander, Tom D; Lind, Tomas; Bottai, Matteo; Eneroth, Kristina M; Caracciolo, Barbara; de Faire, Ulf H; Fratiglioni, Laura; Hilding, Agneta; Leander, Karin; Magnusson, Patrik K E; Pedersen, Nancy L; Östenson, Claes-Göran; Pershagen, Göran; Penell, Johanna C

    2015-01-01

    We investigated the risk of stroke related to long-term ambient air pollution exposure, in particular the role of various exposure time windows, using four cohorts from Stockholm County, Sweden. In total, 22,587 individuals were recruited from 1992 to 2004 and followed until 2011. Yearly air pollution levels resulting from local road traffic emissions were assessed at participant residences using dispersion models for particulate matter (PM10) and nitrogen oxides (NOX). Cohort-specific hazard ratios were estimated for time-weighted air pollution exposure during different time windows and the incidence of stroke, adjusted for common risk factors, and then meta-analysed. Overall, 868 subjects suffered a non-fatal or fatal stroke during 238,731 person-years of follow-up. An increment of 20 μg/m(3) in estimated annual mean of road-traffic related NOX exposure at recruitment was associated with a hazard ratio of 1.16 (95% CI 0.83-1.61), with evidence of heterogeneity between the cohorts. For PM10, an increment of 10 μg/m(3) corresponded to a hazard ratio of 1.14 (95% CI 0.68-1.90). Time-window analyses did not reveal any clear induction-latency pattern. In conclusion, we found suggestive evidence of an association between long-term exposure to NOX and PM10 from local traffic and stroke at comparatively low levels of air pollution.

  6. Influence of traffic-related noise and air pollution on self-reported fatigue.

    Science.gov (United States)

    Jazani, Reza Khani; Saremi, Mahnaz; Rezapour, Tara; Kavousi, Amir; Shirzad, Hadi

    2015-01-01

    A growing body of evidence suggests that exposure to environmental pollutions is related to health problems. It is, however, questionable whether this condition affects working performance in occupational settings. The aim of this study is to determine the predictive value of age as well as traffic related air and noise pollutions for fatigue. 246 traffic officers participated in this study. Air pollution data were obtained from the local Air Quality Control Company. A sound level meter was used for measuring ambient noise. Fatigue was evaluated by the MFI-20 questionnaire. The general and physical scales showed the highest, while the reduced activity scale showed the lowest level of fatigue. Age had an independent direct effect on reduced activity and physical fatigue. The average of daytime equivalent noise level was between 71.63 and 88.51 dB(A). In the case of high noise exposure, older officers feel more fatigue than younger ones. Exposure to PM10 and O3 resulted in general and physical fatigue. Complex Interactions between SO2, CO and NO2 were found. Exposure to noise and some components of air pollution, especially O3 and PM10, increases fatigue. The authorities should adopt and rigorously implement environmental protection policies in order to protect people.

  7. Model for estimating air pollutant uptake by forests: calculation of forest absorption of sulfur dioxide from dispersed sources

    International Nuclear Information System (INIS)

    Murphy, C.E. Jr.; Sinclair, T.R.; Knoerr, K.R.

    1975-01-01

    The computer model presented in this paper is designed to estimate the uptake of air pollutants by forests. The model utilizes submodels to describe atmospheric diffusion immediately above and within the canopy, and into the sink areas within or on the trees. The program implementing the model is general and can be used with only minor changes for any gaseous pollutant. To illustrate the utility of the model, estimates are made of the sink strength of forests for sulfur dioxide. The results agree with experimentally derived estimates of sulfur dioxide uptake in crops and forest trees. (auth)

  8. Individual traffic-related air pollution and new onset adult asthma:A GIS-based pilot study

    DEFF Research Database (Denmark)

    Lysbeck Hansen, Carl; Jensen, Steen Solvang; Baelum, Jesper

    The background for the project is that traffic-related air pollution may provoke the onset of asthma. The objective of this pilot study is to investigate the relation between asthma and wheeze debut and individually estimated exposure to traffic-related air pollutants with a validated exposure...... system (AirGIS). The project applied the following methodology. A non-smoking cohort with recently acquired asthma or wheeze as well as matched controls were identified from a large cross-sectional study. All residential and working addresses with corresponding time periods for a 10 year period were...... successfully identified for all study participants (N=33). Using AirGIS traffic-related air pollutant levels from both urban background and street level were estimated for the 10 year study period on an hourly basis. Individual levels of air pollutants in the years preceding debut of asthma or wheeze were...

  9. CONTRIBUTION FOR MINING ATMOSPHERE CALCULATION

    Directory of Open Access Journals (Sweden)

    Franica Trojanović

    1989-12-01

    Full Text Available Humid air is an unavoidable feature of mining atmosphere, which plays a significant role in defining the climate conditions as well as permitted circumstances for normal mining work. Saturated humid air prevents heat conduction from the human body by means of evaporation. Consequently, it is of primary interest in the mining practice to establish the relative air humidity either by means of direct or indirect methods. Percentage of water in the surrounding air may be determined in various procedures including tables, diagrams or particular calculations, where each technique has its specific advantages and disadvantages. Classical calculation is done according to Sprung's formula, in which case partial steam pressure should also be taken from the steam table. The new method without the use of diagram or tables, established on the functional relation of pressure and temperature on saturated line, is presented here for the first time (the paper is published in Croatian.

  10. Relationship between atomically related core levels and ground state properties of solids: first-principles calculations

    Czech Academy of Sciences Publication Activity Database

    Vackář, Jiří; Šipr, Ondřej; Šimůnek, Antonín

    2008-01-01

    Roč. 77, č. 4 (2008), 045112/1-045112/6 ISSN 1098-0121 R&D Projects: GA AV ČR IAA100100514; GA AV ČR(CZ) IAA100100637 Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z10100521 Keywords : core levels * ab-initio calculations * electronic states * ground state properties Subject RIV: BE - Theoretical Physics Impact factor: 3.322, year: 2008

  11. Calculation of the yearly energy performance of heating systems based on the European Building Energy Directive and related CEN Standards

    DEFF Research Database (Denmark)

    Olesen, Bjarne W.; de Carli, Michele

    2011-01-01

    According to the Energy Performance of Buildings Directive (EPBD) all new European buildings (residential, commercial, industrial, etc.) must since 2006 have an energy declaration based on the calculated energy performance of the building, including heating, ventilating, cooling and lighting syst......–20% of the building energy demand. The additional loss depends on the type of heat emitter, type of control, pump and boiler. Keywords: Heating systems; CEN standards; Energy performance; Calculation methods......According to the Energy Performance of Buildings Directive (EPBD) all new European buildings (residential, commercial, industrial, etc.) must since 2006 have an energy declaration based on the calculated energy performance of the building, including heating, ventilating, cooling and lighting...... systems. This energy declaration must refer to the primary energy or CO2 emissions. The European Organization for Standardization (CEN) has prepared a series of standards for energy performance calculations for buildings and systems. This paper presents related standards for heating systems. The relevant...

  12. Low-level coal combustion as an important problem related to air pollution in Silesia

    International Nuclear Information System (INIS)

    Fudala, J.

    1994-01-01

    Statistical analyses of pollutants from the Katowice District for many years have attributed to the poor air quality to industrial emission sources. Among the source categories for which pollutant emissions into the atmosphere have not been recognized in detail so far, municipal heat sources are worth mentioning. These sources include local boiler houses, residual space heating plants, and individual ceramic furnaces. The problem was investigated by the Institute of Environmental Protection in cooperation with the Regional Design Office at Zabrze. The inventory covered three heat sources: (1) local boiler houses, (2) individual furnaces in multiple-family houses, and (3) individual ceramic furnaces in private houses. For each administrative unit within the district, concentration levels for boiler house and individual household furnaces have been calculated for both local sources and external sources. the calculations have shown that more than 80% of the local concentration levels come from individual furnaces. It also has been found that emissions within a given administrative unit are considerably affected by similar source types in the neighboring units. This relationship has been used to evaluate the administrative units in the Katowice District. In light of the analyses performed, the general conclusion can be drawn the improvement in the sanitary quality of the air depends not only on local emission abatement, but also on integrated activity within the heat and gas supply for old flats and individual private house in the Katowice District

  13. Spatial resolution requirements for traffic-related air pollutant exposure evaluations

    Science.gov (United States)

    Batterman, Stuart; Chambliss, Sarah; Isakov, Vlad

    2014-09-01

    Vehicle emissions represent one of the most important air pollution sources in most urban areas, and elevated concentrations of pollutants found near major roads have been associated with many adverse health impacts. To understand these impacts, exposure estimates should reflect the spatial and temporal patterns observed for traffic-related air pollutants. This paper evaluates the spatial resolution and zonal systems required to estimate accurately intraurban and near-road exposures of traffic-related air pollutants. The analyses use the detailed information assembled for a large (800 km2) area centered on Detroit, Michigan, USA. Concentrations of nitrogen oxides (NOx) due to vehicle emissions were estimated using hourly traffic volumes and speeds on 9700 links representing all but minor roads in the city, the MOVES2010 emission model, the RLINE dispersion model, local meteorological data, a temporal resolution of 1 h, and spatial resolution as low as 10 m. Model estimates were joined with the corresponding shape files to estimate residential exposures for 700,000 individuals at property parcel, census block, census tract, and ZIP code levels. We evaluate joining methods, the spatial resolution needed to meet specific error criteria, and the extent of exposure misclassification. To portray traffic-related air pollutant exposure, raster or inverse distance-weighted interpolations are superior to nearest neighbor approaches, and interpolations between receptors and points of interest should not exceed about 40 m near major roads, and 100 m at larger distances. For census tracts and ZIP codes, average exposures are overestimated since few individuals live very near major roads, the range of concentrations is compressed, most exposures are misclassified, and high concentrations near roads are entirely omitted. While smaller zones improve performance considerably, even block-level data can misclassify many individuals. To estimate exposures and impacts of traffic-related

  14. House Owners’ Interests and Actions in Relation to Indoor Temperature, Air Quality and Energy Use

    DEFF Research Database (Denmark)

    Knudsen, Henrik Nellemose; Andersen, Rune Korsholm; Hansen, Anders Rhiger

    2016-01-01

    in saving energy for the sake of the environment and for their own economy, and quite a lot of households indicate that they know their own energy consumption, though only few follow it closely. Thus being concerned about energy is not necessarily related to an interest in detailed feedback on one’s own......In order to make better and more realistic predictions of energy consumption in dwellings, more knowledge is needed about how individuals and households control the indoor environment. A questionnaire survey was conducted with the objective of studying the interest and actions taken in relation...... to indoor temperature, air quality and energy consumption by Danish house owners living in single-family detached houses with district heating. The house owners state that they are interested in, and concerned about, the indoor temperature and air quality and that it is an important element in caring...

  15. [Examination of work-related stress and coping strategies among ambulance- and air-ambulance workers].

    Science.gov (United States)

    Schiszler, Bence; Karamánné Pakai, Annamária; Szabó, Zoltán; Raposa, László Bence; Pónusz, Róbert; Radnai, Balázs; Endrei, Dóra

    2016-11-01

    Among Hungary's health sector workers the presence of a high level of stress is known, which can affect the individual. The aim of the authors was to uncover major risk factors causing work-related stress, as well as its extent, and positive and negative coping strategies among ground and aerial rescue workers. From June until October 2015, a national survey was conducted among Hungarian rescue workers. An own questionnaire and Rahe Stress and coping validated short questionnaire online form were used. A total of 141 persons took part in the survey. As compared to air-ambulance workers, ground rescue workers were exposed to higher work-related stress effects (pStress and Coping Index effective coping mechanisms were observed among air rescue workers (pstress reduction. Orv. Hetil., 2016, 157(45), 1802-1808.

  16. Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, Daniel I. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-07-22

    The Savannah River Site (SRS) disposes of low-level radioactive waste (LLW) and stabilizes high-level radioactive waste (HLW) tanks in the subsurface environment. Calculations used to establish the radiological limits of these facilities are referred to as Performance Assessments (PA), Special Analyses (SA), and Composite Analyses (CA). The objective of this document is to revise existing geochemical input values used for these calculations. This work builds on earlier compilations of geochemical data (2007, 2010), referred to a geochemical data packages. This work is being conducted as part of the on-going maintenance program of the SRS PA programs that periodically updates calculations and data packages when new information becomes available. Because application of values without full understanding of their original purpose may lead to misuse, this document also provides the geochemical conceptual model, the approach used for selecting the values, the justification for selecting data, and the assumptions made to assure that the conceptual and numerical geochemical models are reasonably conservative (i.e., bias the recommended input values to reflect conditions that will tend to predict the maximum risk to the hypothetical recipient). This document provides 1088 input parameters for geochemical parameters describing transport processes for 64 elements (>740 radioisotopes) potentially occurring within eight subsurface disposal or tank closure areas: Slit Trenches (ST), Engineered Trenches (ET), Low Activity Waste Vault (LAWV), Intermediate Level (ILV) Vaults, Naval Reactor Component Disposal Areas (NRCDA), Components-in-Grout (CIG) Trenches, Saltstone Facility, and Closed Liquid Waste Tanks. The geochemical parameters described here are the distribution coefficient, Kd value, apparent solubility concentration, ks value, and the cementitious leachate impact factor.

  17. Air pollution: what matters most? : Physical, chemical and oxidative properties of air pollution components related to toxic effects

    NARCIS (Netherlands)

    Steenhof, M.

    2015-01-01

    Numerous studies have been published on the adverse health effects associated with both short- and long-term exposure to air pollution. Air pollution is a heterogeneous, complex mixture of gases, liquids, and particulate matter (PM). Up to now, PM mass concentration has been the metric of choice to

  18. Socioeconomic Position and Low Birth Weight among Mothers Exposed to Traffic-Related Air Pollution

    Science.gov (United States)

    Habermann, Mateus; Gouveia, Nelson

    2014-01-01

    Background Atmospheric pollution is a major public health concern. It can affect placental function and restricts fetal growth. However, scientific knowledge remains too limited to make inferences regarding causal associations between maternal exposure to air pollution and adverse effects on pregnancy. This study evaluated the association between low birth weight (LBW) and maternal exposure during pregnancy to traffic related air pollutants (TRAP) in São Paulo, Brazil. Methods and findings Analysis included 5,772 cases of term-LBW (<2,500 g) and 5,814 controls matched by sex and month of birth selected from the birth registration system. Mothers’ addresses were geocoded to estimate exposure according to 3 indicators: distance from home to heavy traffic roads, distance-weighted traffic density (DWTD) and levels of particulate matter ≤10 µg/m3 estimated through land use regression (LUR-PM10). Final models were evaluated using multiple logistic regression adjusting for birth, maternal and pregnancy characteristics. We found decreased odds in the risk of LBW associated with DWTD and LUR-PM10 in the highest quartiles of exposure with a significant linear trend of decrease in risk. The analysis with distance from heavy traffic roads was less consistent. It was also observed that mothers with higher education and neighborhood-level income were potentially more exposed to TRAP. Conclusions This study found an unexpected decreased risk of LBW associated with traffic related air pollution. Mothers with advantaged socioeconomic position (SEP) although residing in areas of higher vehicular traffic might not in fact be more expose to air pollution. It can also be that the protection against LBW arising from a better SEP is stronger than the effect of exposure to air pollution, and this exposure may not be sufficient to increase the risk of LBW for these mothers. PMID:25426640

  19. Mechanical and thermomechanical calculations related to the storage of spent nuclear-fuel assemblies in granite

    International Nuclear Information System (INIS)

    Butkovich, T.R.

    1980-05-01

    A generic test of the geologic storage of spent-fuel assemblies is being made at Nevada Test Site. The spent-fuel assemblies were emplaced at a depth of 420 m (1370 ft) below the surface in a typical granite and will be retrieved at a later time. The early time, close-in thermal history of this type of repository is being simulated with spent-fuel and electrically heated canisters in a central drift, with auxiliary heaters in two parallel side drifts. Prior to emplacement of the spent-fuel canisters, preliminary calculations were made using a pair of existing finite-element codes, ADINA and ADINAT

  20. Standard practice for calculation of corrosion rates and related information from electrochemical measurements

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1989-01-01

    1.1 This practice covers the providing of guidance in converting the results of electrochemical measurements to rates of uniform corrosion. Calculation methods for converting corrosion current density values to either mass loss rates or average penetration rates are given for most engineering alloys. In addition, some guidelines for converting polarization resistance values to corrosion rates are provided. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

  1. European inter-comparison of Monte Carlo codes users for the uncertainty calculation of the kerma in air beside a caesium-137 source; Intercomparaison europeenne d'utilisateurs de codes monte carlo pour le calcul d'incertitudes sur le kerma dans l'air aupres d'une source de cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    De Carlan, L.; Bordy, J.M.; Gouriou, J. [CEA Saclay, LIST, Laboratoire National Henri Becquerel, Laboratoire de Metrologie de la Dose 91 - Gif-sur-Yvette (France)

    2010-07-01

    Within the frame of the CONRAD European project (Coordination Network for Radiation Dosimetry), and more precisely within a work group paying attention to uncertainty assessment in computational dosimetry and aiming at comparing different approaches, the authors report the simulation of an irradiator containing a caesium 137 source to calculate the kerma in air as well as its uncertainty due to different parameters. They present the problem geometry, recall the studied issues (kerma uncertainty, influence of capsule source, influence of the collimator, influence of the air volume surrounding the source). They indicate the codes which have been used (MNCP, Fluka, Penelope, etc.) and discuss the obtained results for the first issue

  2. SESAM: a model for the calculation of radiation exposure by emission of pollutants with the exhaust air in the case of a multi-source situation

    International Nuclear Information System (INIS)

    Ehrlich, H.G.; Vogt, K.J.; Brunen, E.

    The report deals with the calculation of the individual radiation exposure in the catchment area of several nuclear emitters. A model and computer program, SESAM - Calculation of the Radiation Exposure by Emission of Pollutants with the Exhaust air in the Case of a Multi-Source Situation -, was developed which makes possible all the evaluations of long-time exposure which are relevant for the licensing process - such as the determination of the maximum individual radiation exposure to the various organs at the worst receiving point - together with the exposure of the environment by several nuclear emission sources - such as, for example, several units of a power plant facility, the various emitters of a waste management center, or even consideration of the previous exposure of a site by nuclear emission sources

  3. Use of preventive measures for air travel-related venous thrombosis in professionals who attend medical conferences

    NARCIS (Netherlands)

    Kuipers, S.; Cannegieter, S. C.; Middeldorp, S.; Rosendaal, F. R.; Büller, H. R.

    2006-01-01

    BACKGROUND: Lack of guidelines for prevention of air travel-related venous thrombosis may lead to excessive use of potentially dangerous precautions. OBJECTIVES: To assess the use of preventive measures for air travel-related thrombosis in professionals employed in the field of thrombosis and

  4. Association between mortality and indicators of traffic-related air pollution in the Netherlands: A cohort study

    NARCIS (Netherlands)

    Hoek, G.; Brunekreef, B.; Goldbohm, S.; Fischer, P.; Brandt, P.A. van den

    2002-01-01

    Background: Long-term exposure to particulate matter air pollution has been associated with increased cardiopulmonary mortality in the USA. We aimed to assess the relation between traffic-related air pollution and mortality in participants of the Netherlands Cohort study on Diet and Cancer (NLCS),

  5. Subterranean termite open-air foraging and tolerance to desiccation: Comparative water relation of two sympatric Macrotermes spp. (Blattodea: Termitidae).

    Science.gov (United States)

    Hu, Jian; Neoh, Kok-Boon; Appel, Arthur G; Lee, Chow-Yang

    2012-02-01

    The foraging patterns of termites are strongly related to physiological limits in overcoming desiccation stress. In this study, we examined moisture preferences and physiological characteristics of Macrotermes carbonarius (Hagen) and M. gilvus (Hagen) as both exhibit conspicuous patterns of foraging activity. Despite both species showing no significant differences in calculated cuticular permeability, and percentage of total body water, they differed greatly in rate of water loss and surface area to volume ratio. For example, M. carbonarius which had a lower surface area to volume ratio (29.26-53.66) showed lower rate of water loss and percentage of total body water loss. This also resulted in higher LT(50) when exposed to extreme conditions (≈2% RH). However, contrasting observations were made in M. gilvus that has smaller size with higher surface area to volume ratio of 40.28-69.75. It is likely that the standard equation for calculating insect surface areas is inadequate for these termite species. The trend was further supported by the result of a moisture preference bioassay that indicated M. carbonarius had a broader range of moisture preference (between 5% and 20%) than M. gilvus which had a relatively narrow moisture preference (only 20%). These results explain why M. carbonarius can tolerate desiccation stress for a longer period foraging above-ground in the open air; while M. gilvus only forages below ground or concealed within foraging mud tubes. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Traffic-related air pollution and obesity formation in children: a longitudinal, multilevel analysis.

    Science.gov (United States)

    Jerrett, Michael; McConnell, Rob; Wolch, Jennifer; Chang, Roger; Lam, Claudia; Dunton, Genevieve; Gilliland, Frank; Lurmann, Fred; Islam, Talat; Berhane, Kiros

    2014-06-09

    Biologically plausible mechanisms link traffic-related air pollution to metabolic disorders and potentially to obesity. Here we sought to determine whether traffic density and traffic-related air pollution were positively associated with growth in body mass index (BMI = kg/m2) in children aged 5-11 years. Participants were drawn from a prospective cohort of children who lived in 13 communities across Southern California (N = 4550). Children were enrolled while attending kindergarten and first grade and followed for 4 years, with height and weight measured annually. Dispersion models were used to estimate exposure to traffic-related air pollution. Multilevel models were used to estimate and test traffic density and traffic pollution related to BMI growth. Data were collected between 2002-2010 and analyzed in 2011-12. Traffic pollution was positively associated with growth in BMI and was robust to adjustment for many confounders. The effect size in the adjusted model indicated about a 13.6% increase in annual BMI growth when comparing the lowest to the highest tenth percentile of air pollution exposure, which resulted in an increase of nearly 0.4 BMI units on attained BMI at age 10. Traffic density also had a positive association with BMI growth, but this effect was less robust in multivariate models. Traffic pollution was positively associated with growth in BMI in children aged 5-11 years. Traffic pollution may be controlled via emission restrictions; changes in land use that promote jobs-housing balance and use of public transit and hence reduce vehicle miles traveled; promotion of zero emissions vehicles; transit and car-sharing programs; or by limiting high pollution traffic, such as diesel trucks, from residential areas or places where children play outdoors, such as schools and parks. These measures may have beneficial effects in terms of reduced obesity formation in children.

  7. Short-term impacts of air pollutants in Switzerland: Preliminary scenario calculations for selected Swiss energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Andreani-Aksoyoglu, S; Keller, J [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    In the frame of the comprehensive assessment of Swiss energy systems, air quality simulations were performed by using a 3-dimensional photo-chemical dispersion model. The objective is to investigate the impacts of pollutants in Switzerland for future options of Swiss energy systems. Four scenarios were investigated: Base Case: simulations with the projected emissions for the year 2030, Scenario 1) all nuclear power plants were replaced by oil-driven combined cycle plants (CCP), Scenarios 2 to 4) traffic emissions were reduced in whole Switzerland as well as in the cities and on the highways separately. Changes in the pollutant concentrations and depositions, and the possible short-term impacts are discussed on the basis of exceedences of critical levels for plants and limits given to protect the public health. (author) 2 figs., 7 refs.

  8. Methodology for the calculation of source terms related to irradiated fuel accumulated away from nuclear power plants

    International Nuclear Information System (INIS)

    Lima Filho, R.M.; Oliveira, L.F.S. de

    1984-01-01

    A general method for the calculation of the time evolution of source terms related to irradiated fuel is presented. Some applications are discussed which indicated that the method can provide important informations for the engineering design and safety analysis of a temporary storage facility of irradiated fuel elements. (Author) [pt

  9. Suicide risk in relation to air pollen counts: a study based on data from Danish registers

    Science.gov (United States)

    Qin, Ping; Waltoft, Berit L; Mortensen, Preben B; Postolache, Teodor T

    2013-01-01

    Objectives Since the well-observed spring peak of suicide incidents coincides with the peak of seasonal aeroallergens as tree-pollen, we want to document an association between suicide and pollen exposure with empirical data from Denmark. Design Ecological time series study. Setting Data on suicide incidents, air pollen counts and meteorological status were retrieved from Danish registries. Participants 13 700 suicide incidents over 1304 consecutive weeks were obtained from two large areas covering 2.86 million residents. Primary and secondary outcome measures Risk of suicide associated with pollen concentration was assessed using a time series Poisson-generalised additive model. Results We noted a significant association between suicide risk and air pollen counts. A change of pollen counts levels from 0 to ‘10–suicides in the population, and from 0 to ‘30–100’ grains, a relative risk of 1.132. The observed association remained significant after controlling for effects of region, calendar time, temperature, cloud cover and humidity. Meanwhile, we observed a significant sex difference that suicide risk in men started to rise when there was a small increase of air pollen, while the risk in women started to rise until pollen grains reached a certain level. High levels of pollen had slightly stronger effect on risk of suicide in individuals with mood disorder than those without the disorder. Conclusions The observed association between suicide risk and air pollen counts supports the hypothesis that aeroallergens, acting as immune triggers, may precipitate suicide. PMID:23793651

  10. Cardiovascular health, traffic-related air pollution and noise: are associations mutually confounded? A systematic review.

    Science.gov (United States)

    Tétreault, Louis-François; Perron, Stéphane; Smargiassi, Audrey

    2013-10-01

    This review assessed the confounding effect of one traffic-related exposure (noise or air pollutants) on the association between the other exposure and cardiovascular outcomes. A systematic review was conducted with the databases Medline and Embase. The confounding effects in studies were assessed by using change in the estimate with a 10 % cutoff point. The influence on the change in the estimate of the quality of the studies, the exposure assessment methods and the correlation between road noise and air pollutions were also assessed. Nine publications were identified. For most studies, the specified confounders produced changes in estimates noise and pollutants, the quality of the study and of the exposure assessment do not seem to influence the confounding effects. Results from this review suggest that confounding of cardiovascular effects by noise or air pollutants is low, though with further improvements in exposure assessment, the situation may change. More studies using pollution indicators specific to road traffic are needed to properly assess if noise and air pollution are subjected to confounding.

  11. Calculations of the relative effectiveness of alanine for neutrons with energies up to 17.1 MeV

    International Nuclear Information System (INIS)

    Gerstenberg, H.M.; Coyne, J.J.

    1990-01-01

    The relative effectiveness (RE) of alanine has been calculated for neutrons using the RE of alanine for charged particles. The neutrons interact with one or more of the elements (hydrogen, carbon, nitrogen and oxygen) that compose the alanine. These interactions produce spectra of secondary charged particles consisting of ions of H, D, He, Be, B, C, N and O. From a combination of the calculated secondary charged particle spectra generated by the slowing down neutrons, and the calculated RE of the ions produced, a RE for the neutrons can be obtained. In addition, lineal energy spectra were determined for neutrons with energies up to 17.1 MeV interacting with alanine. An analytical code was used to calculate these spectra for a 1 μm diameter alanine cell surrounded by an alanine medium. For comparison, similar calculations were made for muscle tissue. Finally, the calculated differential RE was folded with dose distributions to obtain RE-weighted distributions for alanine. (author)

  12. Linear constraint relations in biochemical reaction systems: I. Classification of the calculability and the balanceability of conversion rates.

    Science.gov (United States)

    van der Heijden, R T; Heijnen, J J; Hellinga, C; Romein, B; Luyben, K C

    1994-01-05

    Measurements provide the basis for process monitoring and control as well as for model development and validation. Systematic approaches to increase the accuracy and credibility of the empirical data set are therefore of great value. In (bio)chemical conversions, linear conservation relations such as the balance equations for charge, enthalpy, and/or chemical elements, can be employed to relate conversion rates. In a pactical situation, some of these rates will be measured (in effect, be calculated directly from primary measurements of, e.g., concentrations and flow rates), as others can or cannot be calculated from the measured ones. When certain measured rates can also be calculated from other measured rates, the set of equations, the accuracy and credibility of the measured rates can indeed be improved by, respectively, balancing and gross error diagnosis. The balanced conversion rates are more accurate, and form a consistent set of data, which is more suitable for further application (e.g., to calculate nonmeasured rates) than the raw measurements. Such an approach has drawn attention in previous studies. The current study deals mainly with the problem of mathematically classifying the conversion rates into balanceable and calculable rates, given the subset of measured rates. The significance of this problem is illustrated with some examples. It is shown that a simple matrix equation can be derived that contains the vector of measured conversion rates and the redundancy matrix R. Matrix R plays a predominant role in the classification problem. In supplementary articles, significance of the redundancy matrix R for an improved gross error diagnosis approach will be shown. In addition, efficient equations have been derived to calculate the balanceable and/or calculable rates. The method is completely based on matrix algebra (principally different from the graph-theoretical approach), and it is easily implemented into a computer program. (c) 1994 John Wiley & Sons

  13. Air and Ground Surface Temperature Relations in a Mountainous Basin, Wolf Creek, Yukon Territory

    Science.gov (United States)

    Roadhouse, Emily A.

    The links between climate and permafrost are well known, but the precise nature of the relationship between air and ground temperatures remains poorly understood, particularly in complex mountain environments. Although previous studies indicate that elevation and potential incoming solar radiation (PISR) are the two leading factors contributing to the existence of permafrost at a given location, additional factors may also contribute significantly to the existence of mountain permafrost, including vegetation cover, snow accumulation and the degree to which individual mountain landscapes are prone to air temperature inversions. Current mountain permafrost models consider only elevation and aspect, and have not been able to deal with inversion effects in a systematic fashion. This thesis explores the relationship between air and ground surface temperatures and the presence of surface-based inversions at 27 sites within the Wolf Creek basin and surrounding area between 2001 and 2006, as a first step in developing an improved permafrost distribution TTOP model. The TTOP model describes the relationship between the mean annual air temperature and the temperature at the top of permafrost in terms of the surface and thermal offsets (Smith and Riseborough, 2002). Key components of this model are n-factors which relate air and ground climate by establishing the ratio between air and surface freezing (winter) and thawing (summer) degree-days, thus summarizing the surface energy balance on a seasonal basis. Here we examine (1) surface offsets and (2) freezing and thawing n-factor variability at a number of sites through altitudinal treeline in the southern Yukon. Thawing n-factors (nt) measured at individual sites remained relatively constant from one year to the next and may be related to land cover. During the winter, the insulating effect of a thick snow cover results in higher surface temperatures, while thin snow cover results in low surface temperatures more closely

  14. Gas-Induced Water-hammer Loads Calculation for Safety Related Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seungchan; Yoon, Dukjoo [Korea Hydro and Nuclear Power Co., LTd, Daejeon (Korea, Republic of); Lee, Dooyong [Seoul National Univ., Seoul (Korea, Republic of)

    2013-05-15

    Of particular interest, gas accumulation can result in system pressure transient in pump discharge piping following a pump start. Consequently, this evolves into a gas-water, a water-hammer event and the accompanying force imbalances on the piping segments can be sufficient to challenge the piping supports and restraint. This paper describes an method performing to the water-hammer loads to determine the maximum loading that would occur in the piping system following the safety injection signal and to evaluate its integrity. For a given gas void volumes in the discharge piping, the result of the calculation shows the maximum loads of 18,894.2psi, which is smaller than the allowable criteria. Also, the maximum peak axial force imbalances acting on the support is 1,720lbf as above.

  15. Gas-Induced Water-hammer Loads Calculation for Safety Related Systems

    International Nuclear Information System (INIS)

    Lee, Seungchan; Yoon, Dukjoo; Lee, Dooyong

    2013-01-01

    Of particular interest, gas accumulation can result in system pressure transient in pump discharge piping following a pump start. Consequently, this evolves into a gas-water, a water-hammer event and the accompanying force imbalances on the piping segments can be sufficient to challenge the piping supports and restraint. This paper describes an method performing to the water-hammer loads to determine the maximum loading that would occur in the piping system following the safety injection signal and to evaluate its integrity. For a given gas void volumes in the discharge piping, the result of the calculation shows the maximum loads of 18,894.2psi, which is smaller than the allowable criteria. Also, the maximum peak axial force imbalances acting on the support is 1,720lbf as above

  16. Traffic-related air pollution and childhood obesity in an Italian birth cohort.

    Science.gov (United States)

    Fioravanti, Sara; Cesaroni, Giulia; Badaloni, Chiara; Michelozzi, Paola; Forastiere, Francesco; Porta, Daniela

    2018-01-01

    Air pollution is associated with several adverse health outcomes in children, such as respiratory illnesses and cognitive development impairment. There are suggestions of an effect of traffic-related air pollution on the occurrence of childhood obesity, but the results are not consistent. The aim of the study is to analyse whether air pollution and vehicular traffic exposure, during the first four years of life, influence obesity- related measures among 4 and 8-year-old children from a prospective birth cohort in Rome. A cohort of newborns, enrolled in 2003-2004 within the GASPII project, was followed at 4 and 8 years of age with parental interviews and clinical examinations. Air pollution was assessed at residential address using Land Use Regression models (for NO 2 , NOx, PM 10 , PM 2.5 , PMcoarse, PM2.5 absorbance and one traffic variable (Total traffic load of all roads in a 100m buffer)). The outcomes under study were body mass index (BMI Z-scores according to WHO recommendations, considered both categorical and continuous) measured at 4 and 8 years, and, waist circumference, waist-to-hip ratio, total and HDL cholesterol measured at 8 years. The associations were evaluated through both cross-sectional and longitudinal approaches, using logistic regression models, Generalized Estimating Equation models (GEE) and linear regression models, as appropriate. Moreover, Inverse Probability Weighting (IPW) methodology was used to account for selection bias at enrolment and at follow-up. A total of 719 infants were enrolled and 581 (80.8%) and 499 (69.4%) were followed at 4 and 8 years, respectively. The prevalence of overweight/obesity was 9.3% and 36.9% at 4 and 8 years. No evidence of an association was found between vehicular traffic and being overweight/obese. Similarly, there was no evidence of an association between exposure to air pollutants and all other ponderal excess parameters. The study shows no association between exposure to vehicular traffic and

  17. Cyclist route choice, traffic-related air pollution, and lung function: a scripted exposure study.

    Science.gov (United States)

    Jarjour, Sarah; Jerrett, Michael; Westerdahl, Dane; de Nazelle, Audrey; Hanning, Cooper; Daly, Laura; Lipsitt, Jonah; Balmes, John

    2013-02-07

    A travel mode shift to active transportation such as bicycling would help reduce traffic volume and related air pollution emissions as well as promote increased physical activity level. Cyclists, however, are at risk for exposure to vehicle-related air pollutants due to their proximity to vehicle traffic and elevated respiratory rates. To promote safe bicycle commuting, the City of Berkeley, California, has designated a network of residential streets as "Bicycle Boulevards." We hypothesized that cyclist exposure to air pollution would be lower on these Bicycle Boulevards when compared to busier roads and this elevated exposure may result in reduced lung function. We recruited 15 healthy adults to cycle on two routes - a low-traffic Bicycle Boulevard route and a high-traffic route. Each participant cycled on the low-traffic route once and the high-traffic route once. We mounted pollutant monitors and a global positioning system (GPS) on the bicycles. The monitors were all synced to GPS time so pollutant measurements could be spatially plotted. We measured lung function using spirometry before and after each bike ride. We found that fine and ultrafine particulate matter, carbon monoxide, and black carbon were all elevated on the high-traffic route compared to the low-traffic route. There were no corresponding changes in the lung function of healthy non-asthmatic study subjects. We also found that wind-speed affected pollution concentrations. These results suggest that by selecting low-traffic Bicycle Boulevards instead of heavily trafficked roads, cyclists can reduce their exposure to vehicle-related air pollution. The lung function results indicate that elevated pollutant exposure may not have acute negative effects on healthy cyclists, but further research is necessary to determine long-term effects on a more diverse population. This study and broader field of research have the potential to encourage policy-makers and city planners to expand infrastructure to

  18. CFD Analysis to Calculate the Optimal Air Velocity in Drying Green Tea Process Using Fluidized Bed Dryer

    Science.gov (United States)

    Yohana, Eflita; Nugraha, Afif Prasetya; Diana, Ade Eva; Mahawan, Ilham; Nugroho, Sri

    2018-02-01

    Tea processing is basically distinguished into three types which black tea, green tea, and oolong tea. Green tea is processed by heating and drying the leaves. Green tea factories in Indonesia are generally using the process of drying by panning the leaves. It is more recommended to use the fluidization process to speed up the drying process as the quality of the tea can be maintained. Bubbling fluidization is expected to occur in this research. It is a process of bubbles are formed in the fluidization. The effectiveness of the drying process in a fluidized bed dryer machine needs to be improved by using a CFD simulation method to proof that umf < u < ut, where the average velocity value is limited by the minimum and the maximum velocity of the calculation the experimental data. The minimum and the maximum velocity value of the fluidization is 0.96 m/s and 8.2 m/s. The result of the simulation obtained that the average velocity of the upper bed part is 1.81 m/s. From the results obtained, it can be concluded that the calculation and the simulation data is in accordance with the condition of bubbling fluidization in fluidized bed dryer.

  19. On the acceptor-related photoluminescence spectra of GaAs quantum-wire microcrystals: A model calculation

    International Nuclear Information System (INIS)

    Oliveira, L.E.; Porras Montenegro, N.; Latge, A.

    1992-07-01

    The acceptor-related photoluminescence spectrum of a GaAs quantum-wire microcrystal is theoretically investigated via a model calculation within the effective-mass approximation, with the acceptor envelope wave functions and binding energies calculated through a variational procedure. Typical theoretical photoluminescence spectra show two peaks associated to transitions from the n = 1 conduction subband electron gas to acceptors at the on-center and on-edge positions in the wire in good agreement with the recent experimental results by Hirum et al. (Appl. Phys. Lett. 59, 431 (1991)). (author). 14 refs, 3 figs

  20. Oxide nanostructures on a Nb surface and related systems: experiments and ab initio calculations

    International Nuclear Information System (INIS)

    Kuznetsov, Mikhail V; Razinkin, A S; Ivanovskii, Alexander L

    2011-01-01

    This review discusses the state of the art in two related research areas: the surfaces of niobium and of its related group IV-VI transition metals, and surface (primarily oxide) nanostructures that form on niobium (and group IV-VI d-metals) due to gas adsorption or impurity diffusion from the bulk. Experimental (X-ray photoelectron spectroscopy, photoelectron diffraction, scanning tunneling microscopy) and theoretical (ab initio simulation) results on d-metal surfaces are summarized and reviewed. (reviews of topical problems)

  1. Total deposition of inhaled particles related to age: comparison with age-dependent model calculations

    International Nuclear Information System (INIS)

    Becquemin, M.H.; Bouchikhi, A.; Yu, C.P.; Roy, M.

    1991-01-01

    To compare experimental data with age-dependent model calculations, total airway deposition of polystyrene aerosols (1, 2.05 and 2.8 μm aerodynamic diameter) was measured in ten adults, twenty children aged 12 to 15 years, ten children aged 8 to 12, and eleven under 8 years old. Ventilation was controlled, and breathing patterns were appropriate for each age, either at rest or at light exercise. Individually, deposition percentages increased with particle size and also from rest to exercise, except in children under 12 years, in whom they decreased from 20-21.5 to 14-14.5 for 1 μm particles and from 36.8-36.9 to 32.2-33.1 for 2.05 μm particles. Comparisons with the age-dependent model showed that, at rest, the observed data concerning children agreed with those predicted and were close to the adults' values, when the latter were higher than predicted. At exercise, child data were lower than predicted and lower than adult experimental data, when the latter agreed fairly well with the model. (author)

  2. Quantum mechanical calculations related to ionization and charge transfer in DNA

    International Nuclear Information System (INIS)

    Cauët, E; Liévin, J; Valiev, M; Weare, J H

    2012-01-01

    Ionization and charge migration in DNA play crucial roles in mechanisms of DNA damage caused by ionizing radiation, oxidizing agents and photo-irradiation. Therefore, an evaluation of the ionization properties of the DNA bases is central to the full interpretation and understanding of the elementary reactive processes that occur at the molecular level during the initial exposure and afterwards. Ab initio quantum mechanical (QM) methods have been successful in providing highly accurate evaluations of key parameters, such as ionization energies (IE) of DNA bases. Hence, in this study, we performed high-level QM calculations to characterize the molecular energy levels and potential energy surfaces, which shed light on ionization and charge migration between DNA bases. In particular, we examined the IEs of guanine, the most easily oxidized base, isolated and embedded in base clusters, and investigated the mechanism of charge migration over two and three stacked guanines. The IE of guanine in the human telomere sequence has also been evaluated. We report a simple molecular orbital analysis to explain how modifications in the base sequence are expected to change the efficiency of the sequence as a hole trap. Finally, the application of a hybrid approach combining quantum mechanics with molecular mechanics brings an interesting discussion as to how the native aqueous DNA environment affects the IE threshold of nucleobases.

  3. Relation between Euclidean and real time calculations of Green functions at finite temperature

    International Nuclear Information System (INIS)

    Bochkarev, A.

    1993-01-01

    We find a relation between the semiclassical approximation of the temperature (Matsubara) two-point correlator and the corresponding classical Green function in real time at finite temperature. The anharmonic oscillator at finite temperature is used to illustrate our statement, which is however of rather general origin

  4. Modeling of heat and momentum exchanges at walls for simulation of air movements in ventilated rooms. Evaluation propositions for professionals; Methodes de calcul des echanges aux parois pour la simulation des ecoulements d'air dans les locaux. Evaluation et propositions pour l'industries

    Energy Technology Data Exchange (ETDEWEB)

    Dondainas, N

    1998-07-01

    This study concerns the calculation methods relative to wall heat transfers in the simulation of air flows inside rooms. Today, there is a real need for a low cost predictive and reliable tool for the prediction of air flows inside buildings or air-conditioned rooms. However, the validity of results is highly dependent to the models used, in particular for the heat and pulse exchanges on walls. This study comprises 3 parts. The first part concerns the convective exchanges. An evaluation of 5 wall turbulence models is made (logarithmic functions model, non-equilibrium model, two-layers model, Lam and Bremhorst low-Reynolds model and modified Lam model). Comparison with experiment is performed on two test cases of the literature: the Cheesewright cavity in natural convection and the Blay cavity in mixed convection. A particular attention is paid to the mesh dependence of results and to the convergence of calculations. The second part concerns the radiant heat transfers between the walls of a room. A new method, called scale change method, is developed for the evaluation of radiant transfers. This method generalizes the fictive cell and radiosity methods. The energy conservation and exchange reciprocity principles are respected. The new method is not a zonal but a field method because net radiant fluxes calculated for each cell wall are variable (the walls are not isothermal). An evaluation of three methods is performed (ray tracing, fictive cell, and the new method) on 4 test cases in 2-D and 3-D geometry with and without mask effect. A particular attention is paid to the processing cost. The third part deals with the study of a real scale atrium. Three air-conditioning configurations are studied. An important part of the study concerns the convection-radiation coupling. Its advantage is to reject the boundary conditions outside the room. (J.S.)

  5. Traffic-Related Air Pollution and Selected Birth Defects in the San Joaquin Valley of California

    Science.gov (United States)

    Padula, Amy M.; Tager, Ira B.; Carmichael, Suzan L.; Hammond, S. Katharine; Yang, Wei; Lurmann, Frederick W.; Shaw, Gary M.

    2014-01-01

    BACKGROUND Birth defects are a leading cause of infant morbidity and mortality. Studies suggest associations between environmental contaminants and some structural anomalies, although evidence is limited and several anomalies have not been investigated previously. METHODS We used data from the California Center of the National Birth Defects Prevention Study and the Children's Health and Air Pollution Study to estimate the odds of 26 congenital birth defect phenotypes with respect to quartiles of seven ambient air pollutant and traffic exposures in California during the first 2 months of pregnancy, 1997 to 2006 (874 cases and 849 controls). We calculated odds ratios (adjusted for maternal race/ethnicity, education, and vitamin use; aOR) for 11 phenotypes that had at least 40 cases. RESULTS Few odds ratios had confidence intervals that did not include 1.0. Odds of esophageal atresia were increased for the highest versus lowest of traffic density (aOR = 2.8, 95% confidence interval [CI], 1.1–7.4) and PM10 exposure (aOR 4.9; 95% CI, 1.4–17.2). PM10 was associated with a decreased risk of hydrocephaly (aOR= 0.3; 95% CI, 0.1–0.9) and CO with decreased risk of anotia/microtia (aOR = 0.4; 95% CI, 0.2–0.8) and transverse limb deficiency (aOR = 0.4; 95% CI, 0.2–0.9), again reflecting highest versus lowest quartile comparisons. CONCLUSION Most analyses showed no substantive association between air pollution and the selected birth defects with few exceptions of mixed results. PMID:24108522

  6. Object–relational architecture of information support of the multi-circuit calculation multilayer semiconductor nanostructures

    Directory of Open Access Journals (Sweden)

    Karina K. Abgaryan

    2015-06-01

    Full Text Available The article examines the object–relational approach to the creation of a database designed to provide informational support to the multiscale computational scheme of multilayer semiconductor nanostructures. The MSNS computational scheme developed earlier by our group uses a hierarchic representation of computational data obtained by various computational modules. Each layer of MSNS is treated separately. In contrast to well-known materials databases which serve for storing and retrieving of information on existing structures and their properties the database described in this paper is the central unit of the MSNS computational scheme. The database provides data interchange between various computational units. In this paper we describe the modern approach to material database design. More specifically, a data storage relational model which applies to solving resource-intensive and different-scale problems is proposed. An object–relational scheduler architecture is used in our work. It provides for high-speed data exchange between various computational units of the MSNS computational scheme. We introduce a simple and user-friendly interface allowing criteria-based data retrieving as well as creation of input files for computational modules. These approaches can be applied in various branches of science, including the aviation and space industry, in particular in control systems of engineering (materials science data.

  7. Proximity to traffic, ambient air pollution, and community noise in relation to incident rheumatoid arthritis.

    Science.gov (United States)

    De Roos, Anneclaire J; Koehoorn, Mieke; Tamburic, Lillian; Davies, Hugh W; Brauer, Michael

    2014-10-01

    The risk of rheumatoid arthritis (RA) has been associated with living near traffic; however, there is evidence suggesting that air pollution may not be responsible for this association. Noise, another traffic-generated exposure, has not been studied as a risk factor for RA. We investigated proximity to traffic, ambient air pollution, and community noise in relation to RA in the Vancouver and Victoria regions of British Columbia, Canada. Cases and controls were identified in a cohort of adults that was assembled using health insurance registration records. Incident RA cases from 1999 through 2002 were identified by diagnostic codes in combination with prescriptions and type of physician (e.g., rheumatologist). Controls were matched to RA cases by age and sex. Environmental exposures were assigned to each member of the study population by their residential postal code(s). We estimated relative risks using conditional logistic regression, with additional adjustment for median income at the postal code. RA incidence was increased with proximity to traffic, with an odds ratio (OR) of 1.37 (95% CI: 1.11, 1.68) for residence ≤ 50 m from a highway compared with residence > 150 m away. We found no association with traffic-related exposures such as PM2.5, nitrogen oxides, or noise. Ground-level ozone, which was highest in suburban areas, was associated with an increased risk of RA (OR = 1.26; 95% CI: 1.18, 1.36 per interquartile range increase). Our study confirms a previously observed association of RA risk with proximity to traffic and suggests that neither noise levels nor traffic-related air pollutants are responsible for this relationship. Additional investigation of neighborhood and individual correlates of residence near roadways may provide new insight into risk factors for RA.

  8. Performance of the air2stream model that relates air and stream water temperatures depends on the calibration method

    Science.gov (United States)

    Piotrowski, Adam P.; Napiorkowski, Jaroslaw J.

    2018-06-01

    A number of physical or data-driven models have been proposed to evaluate stream water temperatures based on hydrological and meteorological observations. However, physical models require a large amount of information that is frequently unavailable, while data-based models ignore the physical processes. Recently the air2stream model has been proposed as an intermediate alternative that is based on physical heat budget processes, but it is so simplified that the model may be applied like data-driven ones. However, the price for simplicity is the need to calibrate eight parameters that, although have some physical meaning, cannot be measured or evaluated a priori. As a result, applicability and performance of the air2stream model for a particular stream relies on the efficiency of the calibration method. The original air2stream model uses an inefficient 20-year old approach called Particle Swarm Optimization with inertia weight. This study aims at finding an effective and robust calibration method for the air2stream model. Twelve different optimization algorithms are examined on six different streams from northern USA (states of Washington, Oregon and New York), Poland and Switzerland, located in both high mountains, hilly and lowland areas. It is found that the performance of the air2stream model depends significantly on the calibration method. Two algorithms lead to the best results for each considered stream. The air2stream model, calibrated with the chosen optimization methods, performs favorably against classical streamwater temperature models. The MATLAB code of the air2stream model and the chosen calibration procedure (CoBiDE) are available as Supplementary Material on the Journal of Hydrology web page.

  9. The calculation of wall and non-uniformity correction factors for the BIPM air-kerma standard for 60Co using the Monte Carlo code PENELOPE

    International Nuclear Information System (INIS)

    Burns, D.T.

    2002-01-01

    Traditionally, the correction factor k wall for attenuation and scatter in the walls of cavity ionization chamber primary standards has been evaluated experimentally using an extrapolation method. During the past decade, there have been a number of Monte Carlo calculations of k wall indicating that for certain ionization chamber types the extrapolation method may not be valid. In particular, values for k wall have been proposed that, if adopted by each laboratory concerned, would have a significant effect on the results of international comparisons of air-kerma primary standards. The calculations have also proposed new values for the axial component k an of the point-source uniformity correction. Central to the results of international comparisons is the BIPM air-kerma standard. Unlike most others, the BIPM standard is of the parallel-plate design for which the extrapolation method for evaluating k wall should be valid. The value in use at present is k wall =1.0026 (standard uncertainty 0.0008). Rogers and Treurniet calculated the value k wall =1.0014 for the BIPM standard, which is in moderate agreement with the value in use (no overall uncertainty was given). However, they also calculated k an =1.0024 (statistical uncertainty 0.0003) which is very different from the value k an =0.9964 (0.0007) in use at present for the BIPM standard. A new 60 Co facility has recently been installed at the BIPM and the opportunity was taken to re-evaluate the correction factors for the BIPM standard in this new beam. Given that almost all of the Monte Carlo work to date has used the EGS Monte Carlo code, it was decided to use the code PENELOPE. The new source, container, head and collimating jaws were simulated in detail with more that fifty components being modelled, as shown. This model was used to create a phase-space file in the plane 90 cm from the source. The normalized distribution of photon number with energy is shown, where the various sources of scattered photons are

  10. Traffic-related air pollution increased the risk of Parkinson's disease in Taiwan: A nationwide study.

    Science.gov (United States)

    Lee, Pei-Chen; Liu, Li-Ling; Sun, Yu; Chen, Yu-An; Liu, Chih-Ching; Li, Chung-Yi; Yu, Hwa-Lung; Ritz, Beate

    2016-11-01

    Ambient air pollution has been associated with many health conditions, but little is known about its effects on neurodegenerative diseases, such as Parkinson's disease (PD). In this study, we investigated the influence of ambient air pollution on PD in a nationwide population-based case-control study in Taiwan. We identified 11,117 incident PD patients between 2007 and 2009 from the Taiwanese National Health Insurance Research Database and selected 44,468 age- and gender-matched population controls from the longitudinal health insurance database. The average ambient pollutant exposure concentrations from 1998 through the onset of PD were estimated using quantile-based Bayesian Maximum Entropy models. Basing from logistic regression models, we estimated the odds ratios (ORs) and 95% confidence intervals (CIs) of ambient pollutant exposures and PD risk. We observed positive associations between NO x , CO exposures, and PD. In multi-pollutant models, for NO x and CO above the 75th percentile exposure compared with the lowest percentile, the ORs of PD were 1.37 (95% CI=1.23-1.52) and 1.17 (95% CI=1.07-1.27), respectively. This study suggests that ambient air pollution exposure, especially from traffic-related pollutants such as NO x and CO, increases PD risk in the Taiwanese population. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Emergency department visits and 'vog'-related air quality in Hilo, Hawaii

    International Nuclear Information System (INIS)

    Michaud, J.-P.; Grove, J.S.; Krupitsky, Dmitry

    2004-01-01

    Emergency department (ED) visits in Hilo, Hawaii, from January 1997 to May 2001, were examined for associations with volcanic fog, or 'vog', measured as sulfur dioxide (SO 2 ) and submicrometer particulate matter (PM 1 ). Exponential regression models were used with robust standard errors. Four diagnostic groups were examined: asthma/COPD; cardiac; flu, cold, and pneumonia; and gastroenteritis. Before adjustments, highly significant associations with vog-related air quality were seen for all diagnostic groups except gastroenteritis. After adjusting for month, year, and day of the week, only asthma/COPD had consistently positive associations with air quality. The strongest associations were for SO 2 with a 3-day lag (6.8% per 10 ppb; P=0.001) and PM 1 , with a 1-day lag (13.8% per 10 μg/m 3 ; P=0.011). The association of ED visits for asthma/COPD with month of the year was stronger than associations seen with air quality. Although vog appears influential, non-vog factors dominated associations with the frequency of asthma/COPD ED visits

  12. Relative position vectors: an alternative approach to conflict detection in air traffic control.

    Science.gov (United States)

    Vuckovic, Anita; Sanderson, Penelope; Neal, Andrew; Gaukrodger, Stephen; Wong, B L William

    2013-10-01

    We explore whether the visual presentation of relative position vectors (RPVs) improves conflict detection in conditions representing some aspects of future airspace concepts. To help air traffic controllers manage increasing traffic, new tools and systems can automate more cognitively demanding processes, such as conflict detection. However, some studies reveal adverse effects of such tools, such as reduced situation awareness and increased workload. New displays are needed that help air traffic controllers handle increasing traffic loads. A new display tool based on the display of RPVs, the Multi-Conflict Display (MCD), is evaluated in a series of simulated conflict detection tasks. The conflict detection performance of air traffic controllers with the MCD plus a conventional plan-view radar display is compared with their performance with a conventional plan-view radar display alone. Performance with the MCD plus radar was better than with radar alone in complex scenarios requiring controllers to find all actual or potential conflicts, especially when the number of aircraft on the screen was large. However performance with radar alone was better for static scenarios in which conflicts for a target aircraft, or target pair of aircraft, were the focus. Complementing the conventional plan-view display with an RPV display may help controllers detect conflicts more accurately with extremely high aircraft counts. We provide an initial proof of concept that RPVs may be useful for supporting conflict detection in situations that are partially representative of conditions in which controllers will be working in the future.

  13. Emergency department visits and "vog"-related air quality in Hilo, Hawai'i.

    Science.gov (United States)

    Michaud, Jon-Pierre; Grove, John Sinclair; Krupitsky, Dmitry

    2004-05-01

    Emergency department (ED) visits in Hilo, Hawai'i, from January 1997 to May 2001, were examined for associations with volcanic fog, or "vog", measured as sulfur dioxide (SO(2)) and submicrometer particulate matter (PM(1)). Exponential regression models were used with robust standard errors. Four diagnostic groups were examined: asthma/COPD; cardiac; flu, cold, and pneumonia; and gastroenteritis. Before adjustments, highly significant associations with vog-related air quality were seen for all diagnostic groups except gastroenteritis. After adjusting for month, year, and day of the week, only asthma/COPD had consistently positive associations with air quality. The strongest associations were for SO(2) with a 3-day lag (6.8% per 10 ppb; P=0.001) and PM(1), with a 1-day lag (13.8% per 10 microg/m(3); P=0.011). The association of ED visits for asthma/COPD with month of the year was stronger than associations seen with air quality. Although vog appears influential, non-vog factors dominated associations with the frequency of asthma/COPD ED visits.

  14. Fabrication of Free Air Well Type Ionization Chamber and Calculational Assessment and Measurement of Its Operational Characteristics

    Directory of Open Access Journals (Sweden)

    Koroush Arbabi

    2007-12-01

    Full Text Available Introduction: Well type ionization chamber is a measuring device which is used to determine the activity of brachytherapy sources. The chamber has a cylindrical volume in which a cylindrical tube is mounted in the middle of the chamber. For the measurements, the brachytherapy sources are transferred to the middle of the tube. Materials and Methods: For designing the well type chamber, the measurement principals of well type chambers were considered and MCNP-4C code as a calculation tool was used. The designed chamber was simulated and the response of the chamber was evaluated. In this investigation, the chamber operational parameters such as operating voltage, leakage current, reproducibility, reference measuring point, recombination and polarization factors as well as response stability for 137Cs, 57Co and 241Am sources were studied. Results: The chamber leakage currents at the operating voltage in comparison to the chamber response for the measurement of the above mentioned sources were negligible. The responses of the fabricated chamber for these sources are reproducible and its reference measurement position for these sources was obtained at 6 cm from the bottom of the chamber. The recombination factor for the well type chamber was negligible and the polarization factor is close to 1. Therefore, these two factors were not considered in the measurements. The reproducibility of the measurements in different intervals shows the stability of the chamber response for each source. Also the results of the chamber current measurement in term of source strength were compared to the response of the simulated chamber for different source positions and energy ranges of the used sources. Discussion and Conclusion: The results show that the measurement of the reference positions for each source in the simulated and fabricated chamber is quite in a good agreement. Regarding the reliable operational properties of the fabricated chamber, this chamber can be

  15. Association between long-term exposure to traffic-related air pollution and subclinical atherosclerosis: the REGICOR study

    NARCIS (Netherlands)

    Rivera, Marcela; Basagaña, Xavier; Aguilera, Inmaculada; Foraster, Maria; Agis, David; de Groot, Eric; Perez, Laura; Mendez, Michelle A.; Bouso, Laura; Targa, Jaume; Ramos, Rafael; Sala, Joan; Marrugat, Jaume; Elosua, Roberto; Künzli, Nino

    2013-01-01

    Epidemiological evidence of the effects of long-term exposure to air pollution on the chronic processes of atherogenesis is limited. We investigated the association of long-term exposure to traffic-related air pollution with subclinical atherosclerosis, measured by carotid intima media thickness

  16. Applicability of the Environmental Relative Moldiness Index for Quantification of Residential Mold Contamination in an Air Pollution Health Effects Study

    Science.gov (United States)

    As part of the Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS) investigating the respiratory health impacts of traffic-related air pollutants on asthmatic children in Detroit, Michigan, residential dust samples were collected to quantify mold exposure. Sett...

  17. Epigenome-wide meta-analysis of methylation in children related to prenatal NO2 air pollution exposure

    NARCIS (Netherlands)

    Gruzieva, O.; Xu, C.J.; Breton, C.V.; Annesi-Maesano, I.; Antó, J.M.; Auffray, C.; Ballereau, S.; Bellander, T.; Bousquet, J.; Bustamante, M.; Charles, M.A.; de Kluizenaar, Y.; Den Dekker, H.T.; Duijts, L.; Felix, J.F.; Gehring, U.; Guxens, M.; Jaddoe, V.V.W.; Jankipersadsing, S.A.; Merid, S.K.; Kere, J.; Kumar, A.; Lemonnier, N.; Lepeule, J.; Nystad, W.; Page, C.M.; Panasevich, S.; Postma, D.; Slama, R.; Sunyer, J.; Söderhäll, C.; Yao, J.; London, S.J.; Pershagen, G.; Koppelman, G.H.; Melén, E.

    2017-01-01

    Background: Prenatal exposure to air pollution is considered to be associated with adverse effects on child health. This may partly be mediated by mechanisms related to DNA methylation. Objectives: We investigated associations between exposure to air pollution, using nitrogen dioxide (NO2) as

  18. Ademe et Vous. Research Newsletter No. 13, December 2015. Air quality and climate change: two closely-related issues

    International Nuclear Information System (INIS)

    Varet, Anne; Guignard, Stephanie

    2015-12-01

    This Research letter is the last in a series of three letters dedicated to climate change, produced in the run up to COP21. It covers the research carried out and the results obtained, with the support of ADEME, in terms of air quality and climate change. Content: - Air quality and climate change: two closely-related issues; - Significant Results: Implementing solutions to improve air quality in a wider context of climate change; - Meeting...: Vincent-Henri Peuch and Nathalie Poisson: 'Air and climate quality - developing joint solutions: a necessity'

  19. Exposure of pregnant women to cookstove-related household air pollution in urban and periurban Trujillo, Peru.

    Science.gov (United States)

    St Helen, Gideon; Aguilar-Villalobos, Manuel; Adetona, Olorunfemi; Cassidy, Brandon; Bayer, Charlene W; Hendry, Robert; Hall, Daniel B; Naeher, Luke P

    2015-01-01

    Although evidence suggests associations between maternal exposure to air pollution and adverse birth outcomes, pregnant women's exposure to household air pollution in developing countries is understudied. Personal exposures of pregnant women (N = 100) in Trujillo, Peru, to air pollutants and their indoor concentrations were measured. The effects of stove-use-related characteristics and ambient air pollution on exposure were determined using mixed-effects models. Significant differences in 48-hour kitchen concentrations of particulate matter (PM2.5), carbon monoxide (CO), and nitrogen dioxide (NO2) concentrations were observed across fuel types (p health risks even in homes where cleaner burning gas stoves were used.

  20. Relation of air mass history to nucleation events in Po Valley, Italy, using back trajectories analysis

    Directory of Open Access Journals (Sweden)

    L. Sogacheva

    2007-01-01

    Full Text Available In this paper, we study the transport of air masses to San Pietro Capofiume (SPC in Po Valley, Italy, by means of back trajectories analysis. Our main aim is to investigate whether air masses originate over different regions on nucleation event days and on nonevent days, during three years when nucleation events have been continuously recorded at SPC. The results indicate that nucleation events occur frequently in air masses arriving from Central Europe, whereas event frequency is much lower in the air transported from southern directions and from the Atlantic Ocean. We also analyzed the behaviour of meteorological parameters during 96 h transport to SPC, and found that, on average, event trajectories undergo stronger subsidence during the last 12 h before the arrival at SPC than nonevent trajectories. This causes a reversal in the temperature and relative humidity (RH differences between event and nonevent trajectories: between 96 and 12 h back time, temperature is lower and RH is higher for event than nonevent trajectories and between 12 and 0 h vice versa. Boundary layer mixing is stronger along the event trajectories compared to nonevent trajectories. The absolute humidity (AH is similar for the event and nonevent trajectories between about 96 h and about 60 h back time, but after that, the event trajectories AH becomes lower due to stronger rain. We also studied transport of SO2 to SPC, and conclude that although sources in Po Valley most probably dominate the measured concentrations, certain Central and Eastern European sources also make a substantial contribution.

  1. Mortality related to air pollution with the moscow heat wave and wildfire of 2010.

    Science.gov (United States)

    Shaposhnikov, Dmitry; Revich, Boris; Bellander, Tom; Bedada, Getahun Bero; Bottai, Matteo; Kharkova, Tatyana; Kvasha, Ekaterina; Lezina, Elena; Lind, Tomas; Semutnikova, Eugenia; Pershagen, Göran

    2014-05-01

    Prolonged high temperatures and air pollution from wildfires often occur together, and the two may interact in their effects on mortality. However, there are few data on such possible interactions. We analyzed day-to-day variations in the number of deaths in Moscow, Russia, in relation to air pollution levels and temperature during the disastrous heat wave and wildfire of 2010. Corresponding data for the period 2006-2009 were used for comparison. Daily average levels of PM10 and ozone were obtained from several continuous measurement stations. The daily number of nonaccidental deaths from specific causes was extracted from official records. Analyses of interactions considered the main effect of temperature as well as the added effect of prolonged high temperatures and the interaction with PM10. The major heat wave lasted for 44 days, with 24-hour average temperatures ranging from 24°C to 31°C and PM10 levels exceeding 300 μg/m on several days. There were close to 11,000 excess deaths from nonaccidental causes during this period, mainly among those older than 65 years. Increased risks also occurred in younger age groups. The most pronounced effects were for deaths from cardiovascular, respiratory, genitourinary, and nervous system diseases. Continuously increasing risks following prolonged high temperatures were apparent during the first 2 weeks of the heat wave. Interactions between high temperatures and air pollution from wildfires in excess of an additive effect contributed to more than 2000 deaths. Interactions between high temperatures and wildfire air pollution should be considered in risk assessments regarding health consequences of climate change.

  2. Epiphytic macrolichens in relation to air pollutants from industrial centres in Brevil, Porsgrunn and Skien, Norway

    Energy Technology Data Exchange (ETDEWEB)

    Gurholt, G

    1968-01-01

    The distribution of lichens on tree stems on top of exposed hills showed distinct relation to industrial air pollution. The main components of pollution are acidic, but the basic ones are more persistent and raise the pH of the bark. Under conditions of moderate pollution lichens usually characterizing rich bark (Populus) are instead found on ordinarily poor bark (Pinus). Detailed pattern of distribution are consistent with the idea of toxic or favorable down-wind effect, depending on the species of lichen and the species of tree. Some lichen species are restricted to downwind stations, others are absent from the same stations.

  3. Review of nuclear air treatment system related License Event Reports for the period 1985 - 1987

    International Nuclear Information System (INIS)

    Jacox, J.W.

    1989-01-01

    This paper will continue the review of HVAC/NATS related LERS presented at past Air Cleaning Conferences by Dr. D. W. Moeller and his associates. The general approach and format are similar. LER abstracts from mid 1985 through 1987 were reviewed and those related to HVAC/NATS classified and analyzed. The categories were jointly developed by Dr. Moeller, Dr. Casper Sun and myself. In appropriate cases both primary and secondary categories fora problem are given. A basic listing by category and brief statistical review are presented. Additionally a number of categories are discussed in some detail. The categories chosen for specific review are intended to highlight particular problem areas. NUREG/CR-2000 License Event Report (LER) Compilation is the basis for the initial review and coding. In essentially all cases where an LER is classified as of interest the complete LER was obtained and reviewed in full. The intent of this paper is to provide a basis for the industry to document and analyze problem areas that require additional attention. It appears that about 15% of all LERS in the subject period are HVAC/NATS related. This figure is generally consistent with those reported at the 17th DOE Nuclear Air Cleaning Conference. It is hoped that such attention will allow additional resources to be allocated to upgrade systems, procedures and training as well as in some cases government regulation

  4. High Accuracy Acoustic Relative Humidity Measurement inDuct Flow with Air

    Directory of Open Access Journals (Sweden)

    Cees van der Geld

    2010-08-01

    Full Text Available An acoustic relative humidity sensor for air-steam mixtures in duct flow is designed and tested. Theory, construction, calibration, considerations on dynamic response and results are presented. The measurement device is capable of measuring line averaged values of gas velocity, temperature and relative humidity (RH instantaneously, by applying two ultrasonic transducers and an array of four temperature sensors. Measurement ranges are: gas velocity of 0–12 m/s with an error of ±0.13 m/s, temperature 0–100 °C with an error of ±0.07 °C and relative humidity 0–100% with accuracy better than 2 % RH above 50 °C. Main advantage over conventional humidity sensors is the high sensitivity at high RH at temperatures exceeding 50 °C, with accuracy increasing with increasing temperature. The sensors are non-intrusive and resist highly humid environments.

  5. High accuracy acoustic relative humidity measurement in duct flow with air.

    Science.gov (United States)

    van Schaik, Wilhelm; Grooten, Mart; Wernaart, Twan; van der Geld, Cees

    2010-01-01

    An acoustic relative humidity sensor for air-steam mixtures in duct flow is designed and tested. Theory, construction, calibration, considerations on dynamic response and results are presented. The measurement device is capable of measuring line averaged values of gas velocity, temperature and relative humidity (RH) instantaneously, by applying two ultrasonic transducers and an array of four temperature sensors. Measurement ranges are: gas velocity of 0-12 m/s with an error of ± 0.13 m/s, temperature 0-100 °C with an error of ± 0.07 °C and relative humidity 0-100% with accuracy better than 2 % RH above 50 °C. Main advantage over conventional humidity sensors is the high sensitivity at high RH at temperatures exceeding 50 °C, with accuracy increasing with increasing temperature. The sensors are non-intrusive and resist highly humid environments.

  6. Traffic related air pollution : spatial variation, health effects and mitigation measures

    NARCIS (Netherlands)

    Dijkema, M.B.A.

    2011-01-01

    Air pollution is probably the most intensely studied field in today’s environmental health research. The extensive body of literature on health effects associated with air pollution exposure has lead to prioritization of air pollution as public health risk factor and air quality regulations

  7. Full-chain health impact assessment of traffic-related air pollution and childhood asthma.

    Science.gov (United States)

    Khreis, Haneen; de Hoogh, Kees; Nieuwenhuijsen, Mark J

    2018-05-01

    Asthma is the most common chronic disease in children. Traffic-related air pollution (TRAP) may be an important exposure contributing to its development. In the UK, Bradford is a deprived city suffering from childhood asthma rates higher than national and regional averages and TRAP is of particular concern to the local communities. We estimated the burden of childhood asthma attributable to air pollution and specifically TRAP in Bradford. Air pollution exposures were estimated using a newly developed full-chain exposure assessment model and an existing land-use regression model (LUR). We estimated childhood population exposure to NO x and, by conversion, NO 2 at the smallest census area level using a newly developed full-chain model knitting together distinct traffic (SATURN), vehicle emission (COPERT) and atmospheric dispersion (ADMS-Urban) models. We compared these estimates with measurements and estimates from ESCAPE's LUR model. Using the UK incidence rate for childhood asthma, meta-analytical exposure-response functions, and estimates from the two exposure models, we estimated annual number of asthma cases attributable to NO 2 and NO x in Bradford, and annual number of asthma cases specifically attributable to traffic. The annual average census tract levels of NO 2 and NO x estimated using the full-chain model were 15.41 and 25.68 μg/m 3 , respectively. On average, 2.75 μg/m 3 NO 2 and 4.59 μg/m 3 NO x were specifically contributed by traffic, without minor roads and cold starts. The annual average census tract levels of NO 2 and NO x estimated using the LUR model were 21.93 and 35.60 μg/m 3 , respectively. The results indicated that up to 687 (or 38% of all) annual childhood asthma cases in Bradford may be attributable to air pollution. Up to 109 cases (6%) and 219 cases (12%) may be specifically attributable to TRAP, with and without minor roads and cold starts, respectively. This is the first study undertaking full-chain health impact assessment

  8. The effect of flight-related behaviour on the risk of venous thrombosis after air travel.

    Science.gov (United States)

    Schreijer, Anja J M; Cannegieter, Suzanne C; Doggen, Carine J M; Rosendaal, Frits R

    2009-02-01

    In a case-control study including 11,033 participants (The Multiple Environmental and Genetic Assessment of risk factors for venous thrombosis study) on risk factors of venous thrombosis, we studied the effect of flight-related behaviour on the risk of venous thrombosis after air travel. Patients and control subjects received a questionnaire on risk factors for venous thrombosis, including recent travel history and details of their last flight. From this population, 80 patients and 108 control subjects were selected who had recently (1.1-4.4], particularly in those who were obese (OR 6.1; 95% CI: 0.5-76.2). Anxiety (OR 2.5; 95% CI: 0.9-7.0) and sleeping (OR 1.5; 95% CI: 0.7-3.1) may increase the risk slightly. The risk was not affected by alcohol consumption (OR 1.1; 95% CI: 0.5-2.4). Flying business class may lower the risk (OR 0.7; 95% CI: 0.2-1.8). We did not find a protective effect for several measures currently part of standard advice from airlines and clinicians, i.e. drinking non-alcoholic beverages, exercising or wearing stockings. The effect of behavioural factors during flying on the risk of venous thrombosis after air travel is limited. Current advice on prevention of travel-related thrombosis may have to be reconsidered.

  9. Operational evaluation of the RLINE dispersion model for studies of traffic-related air pollutants

    Science.gov (United States)

    Milando, Chad W.; Batterman, Stuart A.

    2018-06-01

    Exposure to traffic-related air pollutants (TRAP) remains a key public health issue, and improved exposure measures are needed to support health impact and epidemiologic studies and inform regulatory responses. The recently developed Research LINE source model (RLINE), a Gaussian line source dispersion model, has been used in several epidemiologic studies of TRAP exposure, but evaluations of RLINE's performance in such applications have been limited. This study provides an operational evaluation of RLINE in which predictions of NOx, CO and PM2.5 are compared to observations at air quality monitoring stations located near high traffic roads in Detroit, MI. For CO and NOx, model performance was best at sites close to major roads, during downwind conditions, during weekdays, and during certain seasons. For PM2.5, the ability to discern local and particularly the traffic-related portion was limited, a result of high background levels, the sparseness of the monitoring network, and large uncertainties for certain processes (e.g., formation of secondary aerosols) and non-mobile sources (e.g., area, fugitive). Overall, RLINE's performance in near-road environments suggests its usefulness for estimating spatially- and temporally-resolved exposures. The study highlights considerations relevant to health impact and epidemiologic applications, including the importance of selecting appropriate pollutants, using appropriate monitoring approaches, considering prevailing wind directions during study design, and accounting for uncertainty.

  10. Sample problem calculations related to two-phase flow transients in a PWR relief-piping network

    International Nuclear Information System (INIS)

    Shin, Y.W.; Wiedermann, A.H.

    1981-03-01

    Two sample problems related with the fast transients of water/steam flow in the relief line of a PWR pressurizer were calculated with a network-flow analysis computer code STAC (System Transient-Flow Analysis Code). The sample problems were supplied by EPRI and are designed to test computer codes or computational methods to determine whether they have the basic capability to handle the important flow features present in a typical relief line of a PWR pressurizer. It was found necessary to implement into the STAC code a number of additional boundary conditions in order to calculate the sample problems. This includes the dynamics of the fluid interface that is treated as a moving boundary. This report describes the methodologies adopted for handling the newly implemented boundary conditions and the computational results of the two sample problems. In order to demonstrate the accuracies achieved in the STAC code results, analytical solutions are also obtained and used as a basis for comparison

  11. Calculation of sample problems related to two-phase flow blowdown transients in pressure relief piping of a PWR pressurizer

    International Nuclear Information System (INIS)

    Shin, Y.W.; Wiedermann, A.H.

    1984-02-01

    A method was published, based on the integral method of characteristics, by which the junction and boundary conditions needed in computation of a flow in a piping network can be accurately formulated. The method for the junction and boundary conditions formulation together with the two-step Lax-Wendroff scheme are used in a computer program; the program in turn, is used here in calculating sample problems related to the blowdown transient of a two-phase flow in the piping network downstream of a PWR pressurizer. Independent, nearly exact analytical solutions also are obtained for the sample problems. Comparison of the results obtained by the hybrid numerical technique with the analytical solutions showed generally good agreement. The good numerical accuracy shown by the results of our scheme suggest that the hybrid numerical technique is suitable for both benchmark and design calculations of PWR pressurizer blowdown transients

  12. Frequency of Home Numeracy Activities Is Differentially Related to Basic Number Processing and Calculation Skills in Kindergartners

    Science.gov (United States)

    Mutaf Yıldız, Belde; Sasanguie, Delphine; De Smedt, Bert; Reynvoet, Bert

    2018-01-01

    Home numeracy has been shown to play an important role in children’s mathematical performance. However, findings are inconsistent as to which home numeracy activities are related to which mathematical skills. The present study disentangled between various mathematical abilities that were previously masked by the use of composite scores of mathematical achievement. Our aim was to shed light on the specific associations between home numeracy and various mathematical abilities. The relationships between kindergartners’ home numeracy activities, their basic number processing and calculation skills were investigated. Participants were 128 kindergartners (Mage = 5.43 years, SD = 0.29, range: 4.88–6.02 years) and their parents. The children completed non-symbolic and symbolic comparison tasks, non-symbolic and symbolic number line estimation tasks, mapping tasks (enumeration and connecting), and two calculation tasks. Their parents completed a home numeracy questionnaire. Results indicated small but significant associations between formal home numeracy activities that involved more explicit teaching efforts (i.e., identifying numerals, counting) and children’s enumeration skills. There was no correlation between formal home numeracy activities and non-symbolic number processing. Informal home numeracy activities that involved more implicit teaching attempts, such as “playing games” and “using numbers in daily life,” were (weakly) correlated with calculation and symbolic number line estimation, respectively. The present findings suggest that disentangling between various basic number processing and calculation skills in children might unravel specific relations with both formal and informal home numeracy activities. This might explain earlier reported contradictory findings on the association between home numeracy and mathematical abilities. PMID:29623055

  13. Frequency of Home Numeracy Activities Is Differentially Related to Basic Number Processing and Calculation Skills in Kindergartners.

    Science.gov (United States)

    Mutaf Yıldız, Belde; Sasanguie, Delphine; De Smedt, Bert; Reynvoet, Bert

    2018-01-01

    Home numeracy has been shown to play an important role in children's mathematical performance. However, findings are inconsistent as to which home numeracy activities are related to which mathematical skills. The present study disentangled between various mathematical abilities that were previously masked by the use of composite scores of mathematical achievement. Our aim was to shed light on the specific associations between home numeracy and various mathematical abilities. The relationships between kindergartners' home numeracy activities, their basic number processing and calculation skills were investigated. Participants were 128 kindergartners ( M age = 5.43 years, SD = 0.29, range: 4.88-6.02 years) and their parents. The children completed non-symbolic and symbolic comparison tasks, non-symbolic and symbolic number line estimation tasks, mapping tasks (enumeration and connecting), and two calculation tasks. Their parents completed a home numeracy questionnaire. Results indicated small but significant associations between formal home numeracy activities that involved more explicit teaching efforts (i.e., identifying numerals, counting) and children's enumeration skills. There was no correlation between formal home numeracy activities and non-symbolic number processing. Informal home numeracy activities that involved more implicit teaching attempts , such as "playing games" and "using numbers in daily life," were (weakly) correlated with calculation and symbolic number line estimation, respectively. The present findings suggest that disentangling between various basic number processing and calculation skills in children might unravel specific relations with both formal and informal home numeracy activities. This might explain earlier reported contradictory findings on the association between home numeracy and mathematical abilities.

  14. How to deal with multiple binding poses in alchemical relative protein-ligand binding free energy calculations.

    Science.gov (United States)

    Kaus, Joseph W; Harder, Edward; Lin, Teng; Abel, Robert; McCammon, J Andrew; Wang, Lingle

    2015-06-09

    Recent advances in improved force fields and sampling methods have made it possible for the accurate calculation of protein–ligand binding free energies. Alchemical free energy perturbation (FEP) using an explicit solvent model is one of the most rigorous methods to calculate relative binding free energies. However, for cases where there are high energy barriers separating the relevant conformations that are important for ligand binding, the calculated free energy may depend on the initial conformation used in the simulation due to the lack of complete sampling of all the important regions in phase space. This is particularly true for ligands with multiple possible binding modes separated by high energy barriers, making it difficult to sample all relevant binding modes even with modern enhanced sampling methods. In this paper, we apply a previously developed method that provides a corrected binding free energy for ligands with multiple binding modes by combining the free energy results from multiple alchemical FEP calculations starting from all enumerated poses, and the results are compared with Glide docking and MM-GBSA calculations. From these calculations, the dominant ligand binding mode can also be predicted. We apply this method to a series of ligands that bind to c-Jun N-terminal kinase-1 (JNK1) and obtain improved free energy results. The dominant ligand binding modes predicted by this method agree with the available crystallography, while both Glide docking and MM-GBSA calculations incorrectly predict the binding modes for some ligands. The method also helps separate the force field error from the ligand sampling error, such that deviations in the predicted binding free energy from the experimental values likely indicate possible inaccuracies in the force field. An error in the force field for a subset of the ligands studied was identified using this method, and improved free energy results were obtained by correcting the partial charges assigned to the

  15. How To Deal with Multiple Binding Poses in Alchemical Relative Protein–Ligand Binding Free Energy Calculations

    Science.gov (United States)

    2016-01-01

    Recent advances in improved force fields and sampling methods have made it possible for the accurate calculation of protein–ligand binding free energies. Alchemical free energy perturbation (FEP) using an explicit solvent model is one of the most rigorous methods to calculate relative binding free energies. However, for cases where there are high energy barriers separating the relevant conformations that are important for ligand binding, the calculated free energy may depend on the initial conformation used in the simulation due to the lack of complete sampling of all the important regions in phase space. This is particularly true for ligands with multiple possible binding modes separated by high energy barriers, making it difficult to sample all relevant binding modes even with modern enhanced sampling methods. In this paper, we apply a previously developed method that provides a corrected binding free energy for ligands with multiple binding modes by combining the free energy results from multiple alchemical FEP calculations starting from all enumerated poses, and the results are compared with Glide docking and MM-GBSA calculations. From these calculations, the dominant ligand binding mode can also be predicted. We apply this method to a series of ligands that bind to c-Jun N-terminal kinase-1 (JNK1) and obtain improved free energy results. The dominant ligand binding modes predicted by this method agree with the available crystallography, while both Glide docking and MM-GBSA calculations incorrectly predict the binding modes for some ligands. The method also helps separate the force field error from the ligand sampling error, such that deviations in the predicted binding free energy from the experimental values likely indicate possible inaccuracies in the force field. An error in the force field for a subset of the ligands studied was identified using this method, and improved free energy results were obtained by correcting the partial charges assigned to the

  16. Projecting future air pollution-related mortality under a changing climate: progress, uncertainties and research needs.

    Science.gov (United States)

    Madaniyazi, Lina; Guo, Yuming; Yu, Weiwei; Tong, Shilu

    2015-02-01

    Climate change may affect mortality associated with air pollutants, especially for fine particulate matter (PM2.5) and ozone (O3). Projection studies of such kind involve complicated modelling approaches with uncertainties. We conducted a systematic review of researches and methods for projecting future PM2.5-/O3-related mortality to identify the uncertainties and optimal approaches for handling uncertainty. A literature search was conducted in October 2013, using the electronic databases: PubMed, Scopus, ScienceDirect, ProQuest, and Web of Science. The search was limited to peer-reviewed journal articles published in English from January 1980 to September 2013. Fifteen studies fulfilled the inclusion criteria. Most studies reported that an increase of climate change-induced PM2.5 and O3 may result in an increase in mortality. However, little research has been conducted in developing countries with high emissions and dense populations. Additionally, health effects induced by PM2.5 may dominate compared to those caused by O3, but projection studies of PM2.5-related mortality are fewer than those of O3-related mortality. There is a considerable variation in approaches of scenario-based projection researches, which makes it difficult to compare results. Multiple scenarios, models and downscaling methods have been used to reduce uncertainties. However, few studies have discussed what the main source of uncertainties is and which uncertainty could be most effectively reduced. Projecting air pollution-related mortality requires a systematic consideration of assumptions and uncertainties, which will significantly aid policymakers in efforts to manage potential impacts of PM2.5 and O3 on mortality in the context of climate change. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  17. An application-oriented concept for calculating environmental impacts through exhaust air emissions from nuclear facilities for sites in the Federal Republic of Germany

    International Nuclear Information System (INIS)

    Brenk, H.D.

    1978-02-01

    For the purposes of this study, the ecological area affected in connection with the radiation exposure of man has been subdivided into a number of major sub-areas (dispersion in air, migration in soil and in vegetation as well as transfer into the food chain, activity distribution in the human organism), enabling an independent analysis, and a relatively synoptic description of the individual sub-areas by means of specific transfer functions. This method permits a largely independent approach to the great variety of individual problems, and a successive adaption to the respective state of scientific knowledge. (orig./HP) [de

  18. Gulf of Mexico Air Quality: CALIPSO Support for Gulf of Mexico Air Quality Relating to the Deepwater Horizon Oil Spill

    Science.gov (United States)

    Nguyen, Myngoc T.; Lapointe, Stephen; Jennings, Brittney; Zoumplis, Angela

    2011-01-01

    On April 20, 2010, an oil platform belonging to BP exploded and leaked a huge volume of oil into the Gulf of Mexico. In an effort to control the spread of the oil, BP applied dispersants such as Corexit and conducted in-situ burnings of the oil. This catastrophe created a complex chain of events that affected not only the fragile water and land ecosystems, but the humans who breathe the air every day. Thousands of people were exposed to fumes associated with oil vapors from the spill, burning of the oil, and the toxic mixture of dispersants. While aiding in clean-up efforts, local fishermen were directly exposure to fumes when working on the Gulf. A notable amount of Gulf Coast residents were also exposed to the oil fumes as seasonal southeasterly winds blew vapors toward land. The Volatile Organic Compounds (VOC) found in oil vapors include: benzene, toluene, ethyl benzene, xylene, naphthalene, hydrogen sulfide and particulate matter (PM). Increases in water temperature and sunlight due to the summer season allow for these VOCs and PM to evaporate into the air more rapidly. Aside from the VOCs found in oil vapors, the dispersant being used to break up the oil is highly toxic and is thought to be even more toxic than the oil itself (EPA website, 2010). To protect human health, the environment, and to make informed policy decisions relevant to the spill, the EPA Region 6 has continuously monitored the affected areas carefully for levels of pollutants in the outdoor air that are associated with petroleum products and the burning of oil along the coast. In an effort to prevent, prepare for, and respond to future oil spills that occur in and around inland waters of the United States, the EPA has been working with local, state, and federal response partners. Air quality measurements were collected by the EPA at five active monitoring systems stationed along the coast.

  19. European comparison of Monte Carlo codes users on the uncertainty calculations of air kerma determined in front of a cesium-137 beam; Intercomparaison europeenne d'utilisateurs de codes Monte Carlo pour le calcul d'incertitudes sur le kerma dans l'air determine dans un faisceau de cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    De carlan, L.; Bordy, J.M.; Gouriou, J. [CEA Saclay, LIST, Laboratoire National Henri Becquerel, Laboratoire de Metrologie de la Dose, 91191 Gif-Sur-Yvette Cedex (France)

    2011-07-15

    Within the framework of the European project CONRAD (Coordinated Network for Radiation Dosimetry, contract FP6-12684) coordinated by EURADOS (European Radiation Dosimetry group), WP4 was devoted to numerical dosimetry under the title 'Uncertainty assessment in computational dosimetry: an intercomparison of approaches'. Within this activity, a working group sent a list of eight exercises, dealing with radiation transport of photons, neutrons, protons and electrons, to be solved by the international community. This paper presents exercise number 4, dealing with the calculation of air kerma for a {sup 137}Cs beam. This problem was aimed at estimating the components of the uncertainty on the air kerma which cannot be measured, namely those due to geometrical data such as the source location, the diameter of the collimator, the material density, etc. 12 institutes of 10 different countries took part in this work, showing the interest in this proposal. (authors)

  20. AIRS Observations Based Evaluation of Relative Climate Feedback Strengths on a GCM Grid-Scale

    Science.gov (United States)

    Molnar, G. I.; Susskind, J.

    2012-12-01

    Climate feedback strengths, especially those associated with moist processes, still have a rather wide range in GCMs, the primary tools to predict future climate changes associated with man's ever increasing influences on our planet. Here, we make use of the first 10 years of AIRS observations to evaluate interrelationships/correlations of atmospheric moist parameter anomalies computed from AIRS Version 5 Level-3 products, and demonstrate their usefulness to assess relative feedback strengths. Although one may argue about the possible usability of shorter-term, observed climate parameter anomalies for estimating the strength of various (mostly moist processes related) feedbacks, recent works, in particular analyses by Dessler [2008, 2010], have demonstrated their usefulness in assessing global water vapor and cloud feedbacks. First, we create AIRS-observed monthly anomaly time-series (ATs) of outgoing longwave radiation, water vapor, clouds and temperature profile over a 10-year long (Sept. 2002 through Aug. 2012) period using 1x1 degree resolution (a common GCM grid-scale). Next, we evaluate the interrelationships of ATs of the above parameters with the corresponding 1x1 degree, as well as global surface temperature ATs. The latter provides insight comparable with more traditional climate feedback definitions (e. g., Zelinka and Hartmann, 2012) whilst the former is related to a new definition of "local (in surface temperature too) feedback strengths" on a GCM grid-scale. Comparing the correlation maps generated provides valuable new information on the spatial distribution of relative climate feedback strengths. We argue that for GCMs to be trusted for predicting longer-term climate variability, they should be able to reproduce these observed relationships/metrics as closely as possible. For this time period the main climate "forcing" was associated with the El Niño/La Niña variability (e. g., Dessler, 2010), so these assessments may not be descriptive of longer

  1. Microbial communities related to volatile organic compound emission in automobile air conditioning units.

    Science.gov (United States)

    Diekmann, Nina; Burghartz, Melanie; Remus, Lars; Kaufholz, Anna-Lena; Nawrath, Thorben; Rohde, Manfred; Schulz, Stefan; Roselius, Louisa; Schaper, Jörg; Mamber, Oliver; Jahn, Dieter; Jahn, Martina

    2013-10-01

    During operation of mobile air conditioning (MAC) systems in automobiles, malodours can occur. We studied the microbial communities found on contaminated heat exchanger fins of 45 evaporators from car MAC systems which were operated in seven different regions of the world and identified corresponding volatile organic compounds. Collected biofilms were examined by scanning electron microscopy and fluorescent in situ hybridization. The detected bacteria were loosely attached to the metal surface. Further analyses of the bacteria using PCR-based single-strand conformation polymorphism and sequencing of isolated 16S rRNA gene fragments identified highly divergent microbial communities with multiple members of the Alphaproteobacteriales, Methylobacteria were the prevalent bacteria. In addition, Sphingomonadales, Burkholderiales, Bacillales, Alcanivorax spp. and Stenotrophomonas spp. were found among many others depending on the location the evaporators were operated. Interestingly, typical pathogenic bacteria related to air conditioning systems including Legionella spp. were not found. In order to determine the nature of the chemical compounds produced by the bacteria, the volatile organic compounds were examined by closed loop stripping analysis and identified by combined gas chromatography/mass spectrometry. Sulphur compounds, i.e. di-, tri- and multiple sulphides, acetylthiazole, aromatic compounds and diverse substituted pyrazines were detected. Mathematical clustering of the determined microbial community structures against their origin identified a European/American/Arabic cluster versus two mainly tropical Asian clusters. Interestingly, clustering of the determined volatiles against the origin of the corresponding MAC revealed a highly similar pattern. A close relationship of microbial community structure and resulting malodours to the climate and air quality at the location of MAC operation was concluded.

  2. Calculation of relative free energies for ligand-protein binding, solvation, and conformational transitions using the GROMOS software.

    Science.gov (United States)

    Riniker, Sereina; Christ, Clara D; Hansen, Halvor S; Hünenberger, Philippe H; Oostenbrink, Chris; Steiner, Denise; van Gunsteren, Wilfred F

    2011-11-24

    The calculation of the relative free energies of ligand-protein binding, of solvation for different compounds, and of different conformational states of a polypeptide is of considerable interest in the design or selection of potential enzyme inhibitors. Since such processes in aqueous solution generally comprise energetic and entropic contributions from many molecular configurations, adequate sampling of the relevant parts of configurational space is required and can be achieved through molecular dynamics simulations. Various techniques to obtain converged ensemble averages and their implementation in the GROMOS software for biomolecular simulation are discussed, and examples of their application to biomolecules in aqueous solution are given. © 2011 American Chemical Society

  3. TopoToolbox: using sensor topography to calculate psychologically meaningful measures from event-related EEG/MEG.

    Science.gov (United States)

    Tian, Xing; Poeppel, David; Huber, David E

    2011-01-01

    The open-source toolbox "TopoToolbox" is a suite of functions that use sensor topography to calculate psychologically meaningful measures (similarity, magnitude, and timing) from multisensor event-related EEG and MEG data. Using a GUI and data visualization, TopoToolbox can be used to calculate and test the topographic similarity between different conditions (Tian and Huber, 2008). This topographic similarity indicates whether different conditions involve a different distribution of underlying neural sources. Furthermore, this similarity calculation can be applied at different time points to discover when a response pattern emerges (Tian and Poeppel, 2010). Because the topographic patterns are obtained separately for each individual, these patterns are used to produce reliable measures of response magnitude that can be compared across individuals using conventional statistics (Davelaar et al. Submitted and Huber et al., 2008). TopoToolbox can be freely downloaded. It runs under MATLAB (The MathWorks, Inc.) and supports user-defined data structure as well as standard EEG/MEG data import using EEGLAB (Delorme and Makeig, 2004).

  4. Air pollution in India and related adverse respiratory health effects: past, present, and future directions.

    Science.gov (United States)

    Khilnani, Gopi C; Tiwari, Pawan

    2018-03-01

    The review describes current status of air pollution in India, summarizes recent research on adverse health effects of ambient and household air pollution, and outlines the ongoing efforts and future actions required to improve air quality and reduce morbidity and mortality because of air pollution in India. Global burden of disease data analysis reveals more than one million premature deaths attributable to ambient air pollution in 2015 in India. More than one million additional deaths can be attributed to household air pollution. Particulate matter with diameter 2.5 μm or less has been causatively linked with most premature deaths. Acute respiratory tract infections, asthma, chronic obstructive pulmonary disease, exacerbations of preexisting obstructive airway disease and lung cancer are proven adverse respiratory effects of air pollution. Targeting air quality standards laid by WHO can significantly reduce morbidity and mortality because of air pollution in India. India is currently exposed to high levels of ambient and household air pollutants. Respiratory adverse effects of air pollution are significant contributors to morbidity and premature mortality in India. Substantial efforts are being made at legislative, administrative, and community levels to improve air quality. However, much more needs to be done to change the 'status quo' and attain the target air quality standards. VIDEO ABSTRACT: http://links.lww.com/COPM/A24.

  5. Polycyclic aromatic hydrocarbons (PAH), nickel and vanadium in air dust from Bahrein (Persian Gulf): Measurements and Puff model calculations for this area during the burning of the oil wells in Kuwait

    International Nuclear Information System (INIS)

    Vaessen, H.A.M.G.; Wilbers, A.A.M.M.; Jekel, A.A.; Van Pul, W.A.J.; Van der Meulen, A.; Bloemen, H.J.Th.; De Boer, J.L.M.

    1993-01-01

    When Kuwait's oil wells were at fire in 1991, air particulate matter (inhalable fraction) was sampled in Bahrain (soot clouds were over that region at that time) and analysed for PAHs, nickel (Ni) and vanadium (V). Also in that period Puff-model calculations were carried out to forecast the dispersion of the combustion products and the impact on the environment in the Persian Gulf region. Based on the outcome of the model calculations and the analytical findings the major conclusions are that: (a) the PAH contamination level of the air particulate matter is equal or below that found for rural areas in the Netherlands and on average one order of magnitude below the findings of the model calculations; (b) there is no link between the air particulate matter content and the PAH contamination measured. The benzo(a)pyrene fraction of the PAH contamination is 10-14% which is surprisingly constant; (c) the strongly significant correlation between the Ni- and V-content both mutually and with respect to the air particulate matter content strongly suggests a common origin i.e. the burning oil wells in Kuwait; (d) the air particulate matter content measured is one up to two orders of magnitudes over the findings of the model calculations; (e) the emission factors applied in the Puff-model calculations, most probably, insufficiently match the combustion conditions of oil wells at fire. 6 figs., 3 tabs.,

  6. The influence of air temperature and relative humidity on dynamics of water potential in Betula pendula (Betulaceae trees

    Directory of Open Access Journals (Sweden)

    G. P. Тikhova

    2017-02-01

    Full Text Available Linear multiple models were developed to describe diurnal and seasonal dynamics of water potential (Ψ of the foliated shoots in the plants of Betula genus related to air temperature and relative humidity in the middle taiga (southern Karelia. The results of the study revealed unidirectional changes, but different effect strength of air temperature and relative humidity on Ψ of the foliated shoots of common silver birch (Betula pendula Roth and curly (Karelian birch (Betula pendula Roth var. carelica. It was shown that increasing air temperature 1°С results in similar decreasing of Ψ value equal to 0.037–0.038 MPa in both of the birches (p > 0.05. Since the diurnal air temperature range achieves 10–15 °С, the contribution of this factor may be up to 0.57 MPa. On the contrary, the contribution of relative air humidity to Ψ value differs significantly in distinct birch forms (p < 0.05. In this case the change range of Ψ value in silver birch and curly birch may be up to 0.46 (0.015 MPa/1 % RH and 0.52 МПа (0.017 MPa/1 % RH, respectively. The results indicate that curly birch responds to the increase of relative air humidity with higher magnification of Ψ in comparison with common silver birch.

  7. Hypertension prevalence and living conditions related to air pollution: results of a national epidemiological study in Lebanon.

    Science.gov (United States)

    Salameh, Pascale; Chahine, Mirna; Hallit, Souheil; Farah, Rita; Zeidan, Rouba Karen; Asmar, Roland; Hosseiny, Hassan

    2018-04-01

    Hypertension is a risk factor of several diseases, linked to high mortality and morbidity, particularly in developing countries. Some studies have linked indoor and outdoor pollution exposure items to hypertension, but results were inconsistent. Our objective was to assess the association of living conditions related to air pollution to hypertension in Lebanon, a Middle Eastern country. A national cross-sectional study was conducted all over Lebanon. Blood pressure and its related medications were assessed to be able to classify participants as hypertensive or not. Moreover, in addition to living conditions related to air pollution exposure, we assessed potential predictors of hypertension, including sociodemographic characteristics, self-reported health information and biological measurements. Furthermore, we assessed dose-effect relationship of air pollution items in relation with hypertension. Living conditions related to indoor and outdoor air pollution exposures were associated with hypertension, with or without taking biological values into account. Moreover, we found a dose-effect relationship of exposure with risk of disease (15% increase in risk of disease for every additional pollution exposure item), after adjustment for sociodemographics and biological characteristics (Ora = 1.15 [1.03-1.28]). Although additional studies would be necessary to confirm these findings, interventions should start to sensitize the population about the effect of air pollution on chronic diseases. The work on reducing pollution and improving air quality should be implemented to decrease the disease burden on the population and health system.

  8. Measurements of VOC/SVOC emission factors from burning incenses in an environmental test chamber: influence of temperature, relative humidity, and air exchange rate.

    Science.gov (United States)

    Manoukian, A; Buiron, D; Temime-Roussel, B; Wortham, H; Quivet, E

    2016-04-01

    This study investigates the influence of three environmental indoor parameters (i.e., temperature, relative humidity, and air exchange rate) on the emission of 13 volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) during incense burning. Experiments have been carried out using an environmental test chamber. Statistical results from a classical two-level full factorial design highlight the predominant effect of ventilation on emission factors. The higher the ventilation, the higher the emission factor. Moreover, thanks to these results, an estimation of the concentration range for the compounds under study can be calculated and allows a quick look of indoor pollution induced by incense combustion. Carcinogenic substances (i.e., benzene, benzo(a)pyrene, and formaldehyde) produced from the incense combustion would be predicted in typical living indoors conditions to reach instantaneous concentration levels close to or higher than air quality exposure threshold values.

  9. Corresponding Relation between Warm Season Precipitation Extremes and Surface Air Temperature in South China

    Institute of Scientific and Technical Information of China (English)

    SUN; Wei; LI; Jian; YU; Ru-Cong

    2013-01-01

    Hourly data of 42 rain gauges over South China during 1966–2005 were used to analyze the corresponding relation between precipitation extremes and surface air temperature in the warm season(May to October).The results show that below 25℃,both daily and hourly precipitation extremes in South China increase with rising temperature.More extreme events transit to the two-time Clausius-Clapeyron(CC)relationship at lower temperatures.Daily as well as hourly precipitation extremes have a decreasing tendency nearly above 25℃,among which the decrease of hourly extremes is much more significant.In order to investigate the efects of rainfall durations,hourly precipitation extremes are presented by short duration and long duration precipitation,respectively.Results show that the dramatic decrease of hourly rainfall intensities above 25℃ is mainly caused by short duration precipitation,and long duration precipitation extremes rarely occur in South China when surface air temperature surpasses 28℃.

  10. Evaluation of air pollution-related risks for Austrian mountain forests

    International Nuclear Information System (INIS)

    Smidt, Stefan; Herman, Friedl

    2004-01-01

    The present paper describes air pollution status and evaluation of risks related to effects of phytotoxic pollutants in the Austrian mountain forests. The results are based on Austrian networks (Forest Inventory, Forest Damage Monitoring System, Austrian Bioindicator Grid), the Austrian sample plots of the European networks of the UN-ECE (ICP Forests, Level I and Level II) and interdisciplinary research approaches. Based on the monitoring data and on modelling and mapping of Critical Thresholds, the evaluation of risk factors was possible. Cause-effect relationships between air pollution and tree responses were shown by tree-physiological measurements. Sulfur impact, proton and lead input, concentrations of nitrogen oxides, nitrogen input and ozone were evaluated. The risk was demonstrated at a regional and large-scale national level. Especially the increasing O 3 level and the accumulation of Pb with altitude present most serious risk for mountain forests. - Despite strong reduction of emissions in Europe, pollutants are still a potential stress factor, especially for sensitive mountain forest ecosystems in Austria

  11. Acute air pollution-related symptoms among residents in Chiang Mai, Thailand.

    Science.gov (United States)

    Wiwatanadate, Phongtape

    2014-01-01

    Open burnings (forest fires, agricultural, and garbage burnings) are the major sources of air pollution in Chiang Mai, Thailand. A time series prospective study was conducted in which 3025 participants were interviewed for 19 acute symptoms with the daily records of ambient air pollutants: particulate matter less than 10 microm in size (PM10), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3). PM10 was positively associated with blurred vision with an adjusted odds ratio (OR) of 1.009. CO was positively associated with lower lung and heart symptoms with adjusted ORs of 1.137 and 1.117. NO2 was positively associated with nosebleed, larynx symptoms, dry cough, lower lung symptoms, heart symptoms, and eye irritation with the range of adjusted ORs (ROAORs) of 1.024 to 1.229. SO2 was positively associated with swelling feet, skin symptoms, eye irritation, red eyes, and blurred vision with ROAORs of 1.205 to 2.948. Conversely, O3 was negatively related to running nose, burning nose, dry cough, body rash, red eyes, and blurred vision with ROAORs of 0.891 to 0.979.

  12. From trees to forest: relational complexity network and workload of air traffic controllers.

    Science.gov (United States)

    Zhang, Jingyu; Yang, Jiazhong; Wu, Changxu

    2015-01-01

    In this paper, we propose a relational complexity (RC) network framework based on RC metric and network theory to model controllers' workload in conflict detection and resolution. We suggest that, at the sector level, air traffic showing a centralised network pattern can provide cognitive benefits in visual search and resolution decision which will in turn result in lower workload. We found that the network centralisation index can account for more variance in predicting perceived workload and task completion time in both a static conflict detection task (Study 1) and a dynamic one (Study 2) in addition to other aircraft-level and pair-level factors. This finding suggests that linear combination of aircraft-level or dyad-level information may not be adequate and the global-pattern-based index is necessary. Theoretical and practical implications of using this framework to improve future workload modelling and management are discussed. We propose a RC network framework to model the workload of air traffic controllers. The effect of network centralisation was examined in both a static conflict detection task and a dynamic one. Network centralisation was predictive of perceived workload and task completion time over and above other control variables.

  13. Links Related to the Indoor Air Quality Building Education and Assessment Model

    Science.gov (United States)

    The Indoor Air Quality Building Education and Assessment Model (I-BEAM) is a guidance tool designed for use by building professionals and others interested in indoor air quality in commercial buildings.

  14. Sophisticated Calculation of the 1oo4-architecture for Safety-related Systems Conforming to IEC61508

    International Nuclear Information System (INIS)

    Hayek, A; Al Bokhaiti, M; Schwarz, M H; Boercsoek, J

    2012-01-01

    With the publication and enforcement of the standard IEC 61508 of safety related systems, recent system architectures have been presented and evaluated. Among a number of techniques and measures to the evaluation of safety integrity level (SIL) for safety-related systems, several measures such as reliability block diagrams and Markov models are used to analyze the probability of failure on demand (PFD) and mean time to failure (MTTF) which conform to IEC 61508. The current paper deals with the quantitative analysis of the novel 1oo4-architecture (one out of four) presented in recent work. Therefore sophisticated calculations for the required parameters are introduced. The provided 1oo4-architecture represents an advanced safety architecture based on on-chip redundancy, which is 3-failure safe. This means that at least one of the four channels have to work correctly in order to trigger the safety function.

  15. Biomonitoring of air pollution in Jamaica through trace-element analysis of epiphytic plants using nuclear and related analytical techniques

    International Nuclear Information System (INIS)

    Vutchkov, M.; Lalor, G.C.; Preston, J.

    1999-01-01

    Air quality has been monitored at selected areas in Jamaica using high volume samplers. The results obtained, showed elevated levels of aluminium in bauxitic areas and very high lead concentrations in urban areas, from 5 to 35 times greater than in rural areas. The lower throughput of the conventional air particulate samplers however, restricts the air quality and health assessment on a nation-wide scale. Biomonitoring offers a cost-effective alternative to air-quality assessment if appropriate indicator species are chosen. The epiphytic lower plants such as lichens and mosses have been used as indicators of regional air quality in several European countries and USA. However, there is not enough studies on lichens and mosses in tropical countries, probably due to the lower occurrence of these species, which cover only 8% of the world's land surface. In Jamaica the epiphytic higher plants, represented by the genus Tillandsia are widely distributed, which make them along with the lichens and mosses potential site-specific bioindicators of air quality. The IAEA Co-ordinated Research Project entitled 'Biomonitoring of Air Pollution in Jamaica Through Trace-Element Analysis of Epiphytic Plants Using Nuclear And Related Analytical Techniques' will address these needs of the country. The primary purpose of the present study was to develop specific bioindicators of atmospheric air pollution in Jamaica, which will provide baseline information for health hazards assessment

  16. Air pollution and children's asthma-related emergency hospital visits in southeastern France.

    Science.gov (United States)

    Mazenq, Julie; Dubus, Jean-Christophe; Gaudart, Jean; Charpin, Denis; Nougairede, Antoine; Viudes, Gilles; Noel, Guilhem

    2017-06-01

    Children's asthma is multifactorial. Environmental factors like air pollution exposure, meteorological conditions, allergens, and viral infections are strongly implicated. However, place of residence has rarely been investigated in connection with these factors. The primary aim of our study was to measure the impact of particulate matter (PM), assessed close to the children's homes, on asthma-related pediatric emergency hospital visits within the Bouches-du-Rhône area in 2013. In a nested case-control study on 3- to 18-year-old children, each control was randomly matched on the emergency room visit day, regardless of hospital. Each asthmatic child was compared to 15 controls. PM 10 and PM 2.5 , meteorological conditions, pollens, and viral data were linked to ZIP code and analyzed by purpose of emergency visit. A total of 68,897 visits were recorded in children, 1182 concerning asthma. Short-term exposure to PM 10 measured near children's homes was associated with excess risk of asthma emergency visits (adjusted odds ratio 1.02 (95% CI 1.01-1.04; p = 0.02)). Male gender, young age, and temperature were other risk factors. Conversely, wind speed was a protective factor. PM 10 and certain meteorological conditions near children's homes increased the risk of emergency asthma-related hospital visits in 3- to 18-year-old children in Bouches-du-Rhône. What is Known: • A relationship between short-term exposure to air pollution and increase in emergency room visits or hospital admissions as a result of increased pollution levels has already been demonstrated. What is New: • This study confirms these results but took into account confounding factors (viral data, pollens, and meteorological conditions) and is based on estimated pollution levels assessed close to the children's homes, rather than those recorded at the hospital. • The study area, the Mediterranean, is favorable to creation of secondary pollutants in these sunny and dry seasons.

  17. Ethylene sensitivity and relative air humidity regulate root hydraulic properties in tomato plants.

    Science.gov (United States)

    Calvo-Polanco, Monica; Ibort, Pablo; Molina, Sonia; Ruiz-Lozano, Juan Manuel; Zamarreño, Angel María; García-Mina, Jose María; Aroca, Ricardo

    2017-11-01

    The effect of ethylene and its precursor ACC on root hydraulic properties, including aquaporin expression and abundance, is modulated by relative air humidity and plant sensitivity to ethylene. Relative air humidity (RH) is a main factor contributing to water balance in plants. Ethylene (ET) is known to be involved in the regulation of root water uptake and stomatal opening although its role on plant water balance under different RH is not very well understood. We studied, at the physiological, hormonal and molecular levels (aquaporins expression, abundance and phosphorylation state), the plant responses to exogenous 1-aminocyclopropane-1-carboxylic acid (ACC; precursor of ET) and 2-aminoisobutyric acid (AIB; inhibitor of ET biosynthesis), after 24 h of application to the roots of tomato wild type (WT) plants and its ET-insensitive never ripe (nr) mutant, at two RH levels: regular (50%) and close to saturation RH. Highest RH induced an increase of root hydraulic conductivity (Lp o ) of non-treated WT plants, and the opposite effect in nr mutants. The treatment with ACC reduced Lp o in WT plants at low RH and in nr plants at high RH. The application of AIB increased Lp o only in nr plants at high RH. In untreated plants, the RH treatment changed the abundance and phosphorylation of aquaporins that affected differently both genotypes according to their ET sensitivity. We show that RH is critical in regulating root hydraulic properties, and that Lp o is affected by the plant sensitivity to ET, and possibly to ACC, by regulating aquaporins expression and their phosphorylation status. These results incorporate the relationship between RH and ET in the response of Lp o to environmental changes.

  18. Subclinical responses in healthy cyclists briefly exposed to traffic-related air pollution: an intervention study

    Directory of Open Access Journals (Sweden)

    Bernard Alfred

    2010-10-01

    Full Text Available Abstract Background Numerous epidemiological studies have demonstrated adverse health effects of a sedentary life style, on the one hand, and of acute and chronic exposure to traffic-related air pollution, on the other. Because physical exercise augments the amount of inhaled pollutants, it is not clear whether cycling to work in a polluted urban environment should be encouraged or not. To address this conundrum we investigated if a bicycle journey along a busy commuting road would induce changes in biomarkers of pulmonary and systematic inflammation in a group of healthy subjects. Methods 38 volunteers (mean age: 43 ± 8.6 years, 26% women cycled for about 20 minutes in real traffic near a major bypass road (road test; mean UFP exposure: 28,867 particles per cm3 in Antwerp and in a laboratory with filtered air (clean room; mean UFP exposure: 496 particles per cm3. The exercise intensity (heart rate and duration of cycling were similar for each volunteer in both experiments. Exhaled nitric oxide (NO, plasma interleukin-6 (IL-6, platelet function, Clara cell protein in serum and blood cell counts were measured before and 30 minutes after exercise. Results Percentage of blood neutrophils increased significantly more (p = 0.004 after exercise in the road test (3.9%; 95% CI: 1.5 to 6.2%; p = 0.003 than after exercise in the clean room (0.2%; 95% CI: -1.8 to 2.2%, p = 0.83. The pre/post-cycling changes in exhaled NO, plasma IL-6, platelet function, serum levels of Clara cell protein and number of total blood leukocytes did not differ significantly between the two scenarios. Conclusions Traffic-related exposure to particles during exercise caused a small increase in the distribution of inflammatory blood cells in healthy subjects. The health significance of this isolated change is unclear.

  19. Relative Order of Sulfuric Acid, Bisulfate, Hydronium, and Cations at the Air-Water Interface.

    Science.gov (United States)

    Hua, Wei; Verreault, Dominique; Allen, Heather C

    2015-11-04

    Sulfuric acid (H2SO4), bisulfate (HSO4(-)), and sulfate (SO4(2-)) are among the most abundant species in tropospheric and stratospheric aerosols due to high levels of atmospheric SO2 emitted from biomass burning and volcanic eruptions. The air/aqueous interfaces of sulfuric acid and bisulfate solutions play key roles in heterogeneous reactions, acid rain, radiative balance, and polar stratospheric cloud nucleation. Molecular-level knowledge about the interfacial distribution of these inorganic species and their perturbation of water organization facilitates a better understanding of the reactivity and growth of atmospheric aerosols and of the aerosol surface charge, thus shedding light on topics of air pollution, climate change, and thundercloud electrification. Here, the air/aqueous interface of NaHSO4, NH4HSO4, and Mg(HSO4)2 salt solutions as well as H2SO4 and HCl acid solutions are investigated by means of vibrational sum frequency generation (VSFG) and heterodyne-detected (HD) VSFG spectroscopy. VSFG spectra of all acid solutions show higher SFG response in the OH-bonded region relative to neat water, with 1.1 M H2SO4 being more enhanced than 1.1 M HCl. In addition, VSFG spectra of bisulfate salt solutions highly resemble that of the dilute H2SO4 solution (0.26 M) at a comparable pH. HD-VSFG (Im χ((2))) spectra of acid and bisulfate salt solutions further reveal that hydrogen-bonded water molecules are oriented preferentially toward the bulk liquid phase. General agreement between Im χ((2)) spectra of 1.1 M H2SO4 and 1.1 M HCl acid solutions indicate that HSO4(-) ions have a similar surface preference as that of chloride (Cl(-)) ions. By comparing the direction and magnitude of the electric fields arising from the interfacial ion distributions and the concentration of each species, the most reasonable relative surface preference that can be deduced from a simplified model follows the order H3O(+) > HSO4(-) > Na(+), NH4(+), Mg(2+) > SO4(2-). Interestingly

  20. Statistical Modelling of Temperature and Moisture Uptake of Biochars Exposed to Selected Relative Humidity of Air

    Directory of Open Access Journals (Sweden)

    Luciane Bastistella

    2018-02-01

    Full Text Available New experimental techniques, as well as modern variants on known methods, have recently been employed to investigate the fundamental reactions underlying the oxidation of biochar. The purpose of this paper was to experimentally and statistically study how the relative humidity of air, mass, and particle size of four biochars influenced the adsorption of water and the increase in temperature. A random factorial design was employed using the intuitive statistical software Xlstat. A simple linear regression model and an analysis of variance with a pairwise comparison were performed. The experimental study was carried out on the wood of Quercus pubescens, Cyclobalanopsis glauca, Trigonostemon huangmosun, and Bambusa vulgaris, and involved five relative humidity conditions (22, 43, 75, 84, and 90%, two mass samples (0.1 and 1 g, and two particle sizes (powder and piece. Two response variables including water adsorption and temperature increase were analyzed and discussed. The temperature did not increase linearly with the adsorption of water. Temperature was modeled by nine explanatory variables, while water adsorption was modeled by eight. Five variables, including factors and their interactions, were found to be common to the two models. Sample mass and relative humidity influenced the two qualitative variables, while particle size and biochar type only influenced the temperature.

  1. Traffic-related air pollution and allergic disease: an update in the context of global urbanization.

    Science.gov (United States)

    Carlsten, Christopher; Rider, Christopher F

    2017-04-01

    The review aims to give an update on the literature around traffic-related air pollution (TRAP) and allergic disease in the context of global urbanization, as the most populous countries in the world face severe TRAP exposure challenges. As research continues to show that gene-environment interactions and epigenetics contribute to the TRAP-allergy link, evidence around the links to climate change grows. Greenspace may provide a buffer to adverse effects of traffic on health, overall, but pose risks in terms of allergic disease. The link between traffic-related pollution and allergy continues to strengthen, in terms of supportive observational findings and mechanistic studies. Levels of TRAP across the world, particularly in Asia, continue to dramatically exceed acceptable levels, suggesting that the related adverse health consequences will accelerate. This could be counterbalanced by primary emission control and urban planning. Attention to combined effects of TRAP and allergen exposure is critical to avoiding misleading inferences drawn though examination only of isolated factors.

  2. Improved ROS defense in the swimbladder of a facultative air-breathing erythrinid fish, jeju, compared to a non-air-breathing close relative, traira.

    Science.gov (United States)

    Pelster, Bernd; Giacomin, Marina; Wood, Chris M; Val, Adalberto L

    2016-07-01

    The jeju Hoplerythrinus unitaeniatus and the traira Hoplias malabaricus are two closely related erythrinid fish, both possessing a two-chambered physostomous swimbladder. In the jeju the anterior section of the posterior bladder is highly vascularized and the swimbladder is used for aerial respiration; the traira, in turn, is a water-breather that uses the swimbladder as a buoyancy organ and not for aerial oxygen uptake. Observation of the breathing behavior under different levels of water oxygenation revealed that the traira started aquatic surface respiration only under severe hypoxic conditions and did not breathe air. In the jeju air-breathing behavior was observed under normoxic conditions, and the frequency of air-breathing was significantly increased under hypoxic conditions. Unexpectedly, even under hyperoxic conditions (30 mg O2 L(-1)) the jeju continued to take air breaths, and compared with normoxic conditions the frequency was not reduced. Because the frequently air-exposed swimbladder tissue faces higher oxygen partial pressures than normally experienced by other fish tissues, it was hypothesized that in the facultative air-breathing jeju, swimbladder tissue would have a higher antioxidative capacity than the swimbladder tissue of the water breathing traira. Measurement of total glutathione (GSSG/GSH) concentration in anterior and posterior swimbladder tissue revealed a higher concentration of this antioxidant in swimbladder tissue as compared to muscle tissue in the jeju. Furthermore, the GSSG/GSH concentration in jeju tissues was significantly higher than in traira tissues. Similarly, activities of enzymes involved in the breakdown of reactive oxygen species were significantly higher in the jeju swimbladder as compared to the traira swimbladder. The results show that the jeju, using the swimbladder as an additional breathing organ, has an enhanced antioxidative capacity in the swimbladder as compared to the traira, using the swimbladder only as a

  3. The Covariance between Air Pollution Annoyance and Noise Annoyance, and Its Relationship with Health-Related Quality of Life

    Science.gov (United States)

    Shepherd, Daniel; Dirks, Kim; Welch, David; McBride, David; Landon, Jason

    2016-01-01

    Air pollution originating from road traffic is a known risk factor of respiratory and cardiovascular disease (both in terms of chronic and acute effects). While adverse effects on cardiovascular health have also been linked with noise (after controlling for air pollution), noise exposure has been commonly linked to sleep impairment and negative emotional reactions. Health is multi-faceted, both conceptually and operationally; Health-Related Quality of Life (HRQOL) is one of many measures capable of probing health. In this study, we examine pre-collected data from postal surveys probing HRQOL obtained from a variety of urban, suburban, and rural contexts across the North Island of New Zealand. Analyses focus on the covariance between air pollution annoyance and noise annoyances, and their independent and combined effects on HRQOL. Results indicate that the highest ratings of air pollution annoyance and noise annoyances were for residents living close to the motorway, while the lowest were for rural residents. Most of the city samples indicated no significant difference between air pollution- and noise-annoyance ratings, and of all of the correlations between air pollution- and noise-annoyance, the highest were found in the city samples. These findings suggest that annoyance is driven by exposure to environmental factors and not personality characteristics. Analysis of HRQOL indicated that air pollution annoyance predicts greater variability in the physical HRQOL domain while noise annoyance predicts greater variability in the psychological, social and environmental domains. The lack of an interaction effect between air pollution annoyance and noise annoyance suggests that air pollution and noise impact on health independently. These results echo those obtained from objective measures of health and suggest that mitigation of traffic effects should address both air and noise pollution. PMID:27509512

  4. The Covariance between Air Pollution Annoyance and Noise Annoyance, and Its Relationship with Health-Related Quality of Life.

    Science.gov (United States)

    Shepherd, Daniel; Dirks, Kim; Welch, David; McBride, David; Landon, Jason

    2016-08-06

    Air pollution originating from road traffic is a known risk factor of respiratory and cardiovascular disease (both in terms of chronic and acute effects). While adverse effects on cardiovascular health have also been linked with noise (after controlling for air pollution), noise exposure has been commonly linked to sleep impairment and negative emotional reactions. Health is multi-faceted, both conceptually and operationally; Health-Related Quality of Life (HRQOL) is one of many measures capable of probing health. In this study, we examine pre-collected data from postal surveys probing HRQOL obtained from a variety of urban, suburban, and rural contexts across the North Island of New Zealand. Analyses focus on the covariance between air pollution annoyance and noise annoyances, and their independent and combined effects on HRQOL. Results indicate that the highest ratings of air pollution annoyance and noise annoyances were for residents living close to the motorway, while the lowest were for rural residents. Most of the city samples indicated no significant difference between air pollution- and noise-annoyance ratings, and of all of the correlations between air pollution- and noise-annoyance, the highest were found in the city samples. These findings suggest that annoyance is driven by exposure to environmental factors and not personality characteristics. Analysis of HRQOL indicated that air pollution annoyance predicts greater variability in the physical HRQOL domain while noise annoyance predicts greater variability in the psychological, social and environmental domains. The lack of an interaction effect between air pollution annoyance and noise annoyance suggests that air pollution and noise impact on health independently. These results echo those obtained from objective measures of health and suggest that mitigation of traffic effects should address both air and noise pollution.

  5. Calculation of gas temperature at the outlet of the combustion chamber and in the air-gas channel of a gas-turbine unit by data of acceptance tests in accordance with ISO

    Science.gov (United States)

    Kostyuk, A. G.; Karpunin, A. P.

    2016-01-01

    This article describes a high accuracy method enabling performance of the calculation of real values of the initial temperature of a gas turbine unit (GTU), i.e., the gas temperature at the outlet of the combustion chamber, in a situation where manufacturers do not disclose this information. The features of the definition of the initial temperature of the GTU according to ISO standards were analyzed. It is noted that the true temperatures for high-temperature GTUs is significantly higher than values determined according to ISO standards. A computational procedure for the determination of gas temperatures in the air-gas channel of the gas turbine and cooling air consumptions over blade rims is proposed. As starting equations, the heat balance equation and the flow mixing equation for the combustion chamber are assumed. Results of acceptance GTU tests according to ISO standards and statistical dependencies of required cooling air consumptions on the gas temperature and the blade metal are also used for calculations. An example of the calculation is given for one of the units. Using a developed computer program, the temperatures in the air-gas channel of certain GTUs are calculated, taking into account their design features. These calculations are performed on the previously published procedure for the detailed calculation of the cooled gas turbine subject to additional losses arising because of the presence of the cooling system. The accuracy of calculations by the computer program is confirmed by conducting verification calculations for the GTU of the Mitsubishi Comp. and comparing results with published data of the company. Calculation data for temperatures were compared with the experimental data and the characteristics of the GTU, and the error of the proposed method is estimated.

  6. Dependence of alpha radionuclide diffusion and deposition on relative air humidity

    International Nuclear Information System (INIS)

    Danis, A.; Ciubotariu, M.; Oncescu, M.; Mocsy, I.; Tomulescu, V.

    2000-01-01

    The diffusion and deposition of the gaseous and solid alpha radionuclides/aerosols depend strongly on the relative air humidity. This dependence gets a great significance in the case of radon and their genetically related alpha radionuclides monitoring in the dwelling and working places for radioprotection purposes, particularly in establishing the equilibrium factor. For the gaseous and solid alpha radionuclides genetically related, Rn-222 and its solid alpha descendants including their aerosols obtained by radionuclide attachments to different particles present in air, the vertical gradient of volume concentrations was experimentally determined. The experiments were performed in: an airtight tubular laboratory chamber, a house cellar (Cluj-Napoca) and the entrance gallery of an abandoned mine (Avram Iancu, Bihor), in which the relative humidity was ranging from 65% up to 96%. For the laboratory chamber, these radionuclides were generated by a calibrated Ra-226 source, prepared at the Radionuclide Production Centre, IPNE-HH, Bucharest. The source was included into an air tight device with a well known volume and it was used only after 40 days, when the Ra-226 and its alpha descendants were under radioactive equilibrium. For the diffusion/deposition studies, this source was coupled with the airtight laboratory chamber. In the mine gallery and house cellar, the radon and its descendants were naturally and continuously generated by radium sources in soil and building materials. The alpha volume concentration determinations required the use of a very accurate and sensitive alpha measurement method. These requirements were met by the alpha track method. This method was used by us in the following conditions: the CR-39 plastic track detector (Page, England) for the detection of the alpha particles and the optical microscopy for the study of alpha tracks (Wild stereomicroscope M7S and a Karl Zeiss Jena binocular microscope). The volume concentrations of radon and the

  7. On the calculation of air flow rates to ventilate closed-type stations in subway with the double-track tunnel

    Science.gov (United States)

    Kiyanitsa, LA

    2018-03-01

    Metro is not only the most promising kind of public transport but also an important part of infrastructure in a modern city. As a place where large groups of people gather, subway is to ensure the required air exchange at the passenger platforms of the stations. The air flow rate for airing the stations is also determined based on the required temperature, humidity and MAC of gases. The present study estimates the required air flow rate at the passenger platform of the closed-type subway station with the double-track tunnel given the standard air temperature, humidity and gas concentration, as well as based on the condition of the specified air flow feed and air changes per hour. The article proposes the scheme of air recirculation from the double-track tunnel to the station.

  8. Revision to the humidity correction equation in the calculation formulae of the air refractive index based on a phase step interferometer with three frequency-stabilized lasers

    International Nuclear Information System (INIS)

    Chen, Qianghua; Zhang, Mengce; Liu, Shuaijie; He, Yongxi; Luo, Huifu; Luo, Jun; Lv, Weiwei

    2016-01-01

    At present the formulae proposed by G Boensch and E Potulski in 1998 (Boensch and Potulski 1998 Metrologia 35 133–9) are mostly used to calculate the air refractive index. However, the humidity correction equation in the formulae is derived by using the light source of a Cd lamp whose light frequency stability is poor and at a narrow temperature range, around 20 °C. So it is no longer suitable in present optical precision measurements. To solve this problem, we propose a refractive index measurement system based on phase step interferometer with three frequency stabilized lasers (532 nm, 633 nm, 780 nm), corrected coefficients of the humidity are measured and a corresponding revised humidity correction equation is acquired. Meanwhile, the application temperature range is extended from 14.6 °C to 25.0 °C. The experiment comparison results at the temperature of 22.2–23.2 °C show the accuracy by the presented equation is better than that of Boensch and Potulski. (paper)

  9. Traffic-related air quality trends in São Paulo, Brazil

    Science.gov (United States)

    Pérez-Martínez, Pedro José; de Fátima Andrade, María.; de Miranda, Regina Maura

    2015-06-01

    The urban population of South America has grown at 1.05%/yr, greater urbanization increasing problems related to air pollution. In most large cities in South America, there has been no continuous long-term measurement of regulated pollutants. One exception is São Paulo, Brazil, where an air quality monitoring network has been in place since the 1970s. In this paper, we used an air quality-based approach to determine pollutant trends for emissions of carbon monoxide (CO), nitrogen oxides (NOx), ozone (O3), and coarse particulate matter (PM10), mostly from mobile sources, in the Metropolitan Region of São Paulo for the 2000-2013 period. Mobile sources included light-duty vehicles (LDVs, comprising gasoline- or ethanol-powered cars and motorcycles) and heavy-duty vehicles (HDVs, comprising diesel-powered trucks and buses). Pollutant concentrations for mobile source emissions were measured and correlated with fuel sales by the emission factors. Over the 2000-2013 period, concentrations of NOx, CO, and PM10 decreased by 0.65, 0.37, and 0.71% month-1, respectively, whereas sales of gasoline, ethanol, and diesel increased by 0.26, 1.96, and 0.38% month-1, respectively. LDVs were the major mobile source of CO, whereas LDVs were the major source of NOx and PM10. Increases in fuel sales and in the corresponding traffic volume were partially offset by decreases in pollutant concentrations. Between 2000 and 2013, there was a sharp (-5 ppb month-1) decrease in the concentrations of LDV-emitted CO, together with (less dramatic) decreases in the concentrations of HDV-emitted NOx and PM10 (-0.25 and -0.09 ppb month-1, respectively). Variability was greater for HDV-emitted NOx and PM10 (R = -0.47 and -0.41, respectively) than for LDV-emitted CO (R = -0.72). We draw the following conclusions: the observed concentrations of LDV-emitted CO decreased at a sharper rate than did those of HDV-emitted NOx and PM10; mobile source contributions to O3 formation varied significantly, LDVs

  10. Influence of relative humidity of air on the level of aqueous tritium in corn, wheat and sunflower

    International Nuclear Information System (INIS)

    Indeka, L.

    1981-01-01

    The short-term changes in level of aqueous tritium in the leaves in relation to the air humidity were studied. The experiments were carried out on corn in which the transpiration is relatively small, on sunflower with very high transpiration and on wheat with intermediate transpiration. (M.F.W.)

  11. Predicting long-term average concentrations of traffic-related air pollutants using GIS-based information

    Science.gov (United States)

    Hochadel, Matthias; Heinrich, Joachim; Gehring, Ulrike; Morgenstern, Verena; Kuhlbusch, Thomas; Link, Elke; Wichmann, H.-Erich; Krämer, Ursula

    Global regression models were developed to estimate individual levels of long-term exposure to traffic-related air pollutants. The models are based on data of a one-year measurement programme including geographic data on traffic and population densities. This investigation is part of a cohort study on the impact of traffic-related air pollution on respiratory health, conducted at the westerly end of the Ruhr-area in North-Rhine Westphalia, Germany. Concentrations of NO 2, fine particle mass (PM 2.5) and filter absorbance of PM 2.5 as a marker for soot were measured at 40 sites spread throughout the study region. Fourteen-day samples were taken between March 2002 and March 2003 for each season and site. Annual average concentrations for the sites were determined after adjustment for temporal variation. Information on traffic counts in major roads, building densities and community population figures were collected in a geographical information system (GIS). This information was used to calculate different potential traffic-based predictors: (a) daily traffic flow and maximum traffic intensity of buffers with radii from 50 to 10 000 m and (b) distances to main roads and highways. NO 2 concentration and PM 2.5 absorbance were strongly correlated with the traffic-based variables. Linear regression prediction models, which involved predictors with radii of 50 to 1000 m, were developed for the Wesel region where most of the cohort members lived. They reached a model fit ( R2) of 0.81 and 0.65 for NO 2 and PM 2.5 absorbance, respectively. Regression models for the whole area required larger spatial scales and reached R2=0.90 and 0.82. Comparison of predicted values with NO 2 measurements at independent public monitoring stations showed a satisfactory association ( r=0.66). PM 2.5 concentration, however, was only slightly correlated and thus poorly predictable by traffic-based variables ( rGIS-based regression models offer a promising approach to assess individual levels of

  12. [Prevention of Occupational Injuries Related to Hands: Calculation of Subsequent Injury Costs for the Austrian Social Occupational Insurance Institution (AUVA)].

    Science.gov (United States)

    Rauner, M S; Mayer, B; Schaffhauser-Linzatti, M M

    2015-08-01

    Occupational injuries cause short-term, direct costs as well as long-term follow-up costs over the lifetime of the casualties. Due to shrinking budgets accident insurance companies focus on cost reduction programmes and prevention measures. For this reason, a decision support system for consequential cost calculation of occupational injuries was developed for the main Austrian social occupational insurance institution (AUVA) during three projects. This so-called cost calculation tool combines the traditional instruments of accounting with quantitative methods such as micro-simulation. The cost data are derived from AUVA-internal as well as external economic data sources. Based on direct and indirect costs, the subsequent occupational accident costs from the time of an accident and, if applicable, beyond the death of the individual casualty are predicted for the AUVA, the companies in which the casualties are working, and the other economic sectors. By using this cost calculation tool, the AUVA classifies risk groups and derives related prevention campaigns. In the past, the AUVA concentrated on falling, accidents at construction sites and in agriculture/forestry, as well as commuting accidents. Currently, among others, a focus on hand injuries is given and first prevention programmes have been initiated. Hand injuries represent about 38% of all casualties with average costs of about 7,851 Euro/case. Main causes of these accidents are cutting injuries in production, agriculture, and forestry. Beside a low, but costly, number of amputations with average costs of more than 100,000 Euro/case, bone fractures and strains burden the AUVA-budget with about 17,500 and 10,500 € per case, respectively. Decision support systems such as this cost calculation tool represent necessary instruments to identify risk groups and their injured body parts, causes of accidents, and economic activities, which highly burden the budget of an injury company, and help derive

  13. Effects of canyon geometry on the distribution of traffic-related air pollution in a large urban area: Implications of a multi-canyon air pollution dispersion model

    Science.gov (United States)

    Fu, Xiangwen; Liu, Junfeng; Ban-Weiss, George A.; Zhang, Jiachen; Huang, Xin; Ouyang, Bin; Popoola, Olalekan; Tao, Shu

    2017-09-01

    Street canyons are ubiquitous in urban areas. Traffic-related air pollutants in street canyons can adversely affect human health. In this study, an urban-scale traffic pollution dispersion model is developed considering street distribution, canyon geometry, background meteorology, traffic assignment, traffic emissions and air pollutant dispersion. In the model, vehicle exhausts generated from traffic flows first disperse inside street canyons along the micro-scale wind field generated by computational fluid dynamics (CFD) model. Then, pollutants leave the street canyon and further disperse over the urban area. On the basis of this model, the effects of canyon geometry on the distribution of NOx and CO from traffic emissions were studied over the center of Beijing. We found that an increase in building height leads to heavier pollution inside canyons and lower pollution outside canyons at pedestrian level, resulting in higher domain-averaged concentrations over the area. In addition, canyons with highly even or highly uneven building heights on each side of the street tend to lower the urban-scale air pollution concentrations at pedestrian level. Further, increasing street widths tends to lead to lower pollutant concentrations by reducing emissions and enhancing ventilation simultaneously. Our results indicate that canyon geometry strongly influences human exposure to traffic pollutants in the populated urban area. Carefully planning street layout and canyon geometry while considering traffic demand as well as local weather patterns may significantly reduce inhalation of unhealthy air by urban residents.

  14. Analysis of chemistry textbook content and national science education standards in terms of air quality-related learning goals

    Science.gov (United States)

    Naughton, Wendy

    In this study's Phase One, representatives of nine municipal agencies involved in air quality education were interviewed and interview transcripts were analyzed for themes related to what citizens need to know or be able to do regarding air quality concerns. Based on these themes, eight air quality Learning Goal Sets were generated and validated via peer and member checks. In Phase Two, six college-level, liberal-arts chemistry textbooks and the National Science Education Standards (NSES) were analyzed for congruence with Phase One learning goals. Major categories of desired citizen understandings highlighted in agency interviews concerned air pollution sources, impact, detection, and transport. Identified cognitive skills focused on information-gathering and -evaluating skills, enabling informed decision-making. A content match was found between textbooks and air quality learning goals, but most textbooks fail to address learning goals that remediate citizen misconceptions and inabilities---particularly those with a "personal experience" focus. A partial match between NSES and air quality learning goals was attributed to differing foci: Researcher-derived learning goals deal specifically with air quality, while NSES focus is on "fundamental science concepts," not "many science topics." Analysis of findings within a situated cognition framework suggests implications for instruction and NSES revision.

  15. Combined effects of road traffic noise and ambient air pollution in relation to risk for stroke?

    DEFF Research Database (Denmark)

    Sørensen, Mette; Lühdorf, Pernille; Ketzel, Matthias

    2014-01-01

    Exposure to road traffic noise and air pollution have both been associated with risk for stroke. The few studies including both exposures show inconsistent results. We aimed to investigate potential mutual confounding and combined effects between road traffic noise and air pollution in association...... to 2009 were identified in national registers and road traffic noise and air pollution were modeled for all addresses. Analyses were done using Cox regression. A higher mean annual exposure at time of diagnosis of 10µg/m(3) nitrogen dioxide (NO2) and 10dB road traffic noise at the residential address...... was found for combination of high noise and high NO2 (IRR=1.28; 95% CI=1.09-1.52). Fatal stroke was positively associated with air pollution and not with traffic noise. In conclusion, in mutually adjusted models road traffic noise and not air pollution was associated ischemic stroke, while only air...

  16. Calculation of the relative chemical stabilities of proteins as a function of temperature and redox chemistry in a hot spring.

    Directory of Open Access Journals (Sweden)

    Jeffrey M Dick

    Full Text Available Uncovering the chemical and physical links between natural environments and microbial communities is becoming increasingly amenable owing to geochemical observations and metagenomic sequencing. At the hot spring known as Bison Pool in Yellowstone National Park, the cooling of the water in the outflow channel is associated with an increase in oxidation potential estimated from multiple field-based measurements. Representative groups of proteins whose sequences were derived from metagenomic data also exhibit an increase in average oxidation state of carbon in the protein molecules with distance from the hot-spring source. The energetic requirements of reactions to form selected proteins used in the model were computed using amino-acid group additivity for the standard molal thermodynamic properties of the proteins, and the relative chemical stabilities of the proteins were investigated by varying temperature, pH and oxidation state, expressed as activity of dissolved hydrogen. The relative stabilities of the proteins were found to track the locations of the sampling sites when the calculations included a function for hydrogen activity that increases with temperature and is higher, or more reducing, than values consistent with measurements of dissolved oxygen, sulfide and oxidation-reduction potential in the field. These findings imply that spatial patterns in the amino acid compositions of proteins can be linked, through energetics of overall chemical reactions representing the formation of the proteins, to the environmental conditions at this hot spring, even if microbial cells maintain considerably different internal conditions. Further applications of the thermodynamic calculations are possible for other natural microbial ecosystems.

  17. Lichen and bryophyte distribution on oak in London in relation to air pollution and bark acidity

    International Nuclear Information System (INIS)

    Larsen, R.S.; Bell, J.N.B.; James, P.W.; Chimonides, P.J.; Rumsey, F.J.; Tremper, A.; Purvis, O.W.

    2007-01-01

    Epiphytic lichen and bryophyte distribution and frequency were investigated on the trunks of 145 young oak trees throughout London and surrounding counties, and compared with pollution levels and bark pH. Sixty-four lichen and four bryophyte species were recorded. Three major zones were identified: (i) two central regions with a few lichens, bryophytes absent; (ii) a surrounding region with a more diverse flora including a high cover of nitrophyte lichens; and (iii) an outer region, characterised by species absent from central London, including acidophytes. Nineteen species were correlated with nitrogen oxides and 16 with bark pH, suggesting that transport-related pollution and bark acidity influence lichen and bryophyte distribution in London today. Lichens and bryophytes are responding to factors that influence human and environmental health in London. Biomonitoring therefore has a practical role to assess the effects of measures to improve London's air quality. - Transport-related pollutants and bark acidity influence lichen and bryophyte distribution and abundance in London today

  18. Means and method of sampling flow related variables from a waterway in an accurate manner using a programmable calculator

    Science.gov (United States)

    Rand E. Eads; Mark R. Boolootian; Steven C. [Inventors] Hankin

    1987-01-01

    Abstract - A programmable calculator is connected to a pumping sampler by an interface circuit board. The calculator has a sediment sampling program stored therein and includes a timer to periodically wake up the calculator. Sediment collection is controlled by a Selection At List Time (SALT) scheme in which the probability of taking a sample is proportional to its...

  19. Measuring PM and related air pollutants using low-cost sensors

    Science.gov (United States)

    Emerging air quality sensors may play a key role in better characterizing levels of air pollution in a variety of settings There are a wide range of low-cost (sensors on the market, but few have been characterized. If accurate, this new generation of inexpensive sens...

  20. Risk of Air Pollution in Relation to Cancer in the Nordic Countries

    DEFF Research Database (Denmark)

    Fauser, Patrik; Ketzel, Matthias; Becker, Thomas

    Seventeen pollutants (particles, heavy metals, inorganic gases and organic compounds) are for the first time analyzed in a screening of the carcinogenic risk at very high resolution and large scale in ambient air in the Nordic countries. Modelled 2010 annual mean air concentrations show...

  1. Indoor air quality issues related to the acquisition of conservation in commercial buildings

    Energy Technology Data Exchange (ETDEWEB)

    Baechler, M.C.; Hadley, D.L.; Marseille, T.J.

    1990-09-01

    The quality of indoor air in commercial buildings is dependent on the complex interaction between sources of indoor pollutants, environmental factors within buildings such as temperature and humidity, the removal of air pollutants by air-cleaning devices, and the removal and dilution of pollutants from outside air. To the extent that energy conservation measures (ECMs) may affect a number of these factors, the relationship between ECMs and indoor air quality is difficult to predict. Energy conservation measures may affect pollutant levels in other ways. Conservation measures, such as caulking and insulation, may introduce sources of indoor pollutants. Measures that reduce mechanical ventilation may allow pollutants to build up inside structures. Finally, heating, ventilation, and air-conditioning (HVAC) systems may provide surface areas for the growth of biogenic agents, or may encourage the dissemination of pollutants throughout a building. Information about indoor air quality and ventilation in both new and existing commercial buildings is summarized in this report. Sick building syndrome and specific pollutants are discussed, as are broader issues such as ventilation, general mitigation techniques, and the interaction between energy conservation activities and indoor air quality. Pacific Northwest Laboratory (PNL) prepared this review to aid the Bonneville Power Administration (Bonneville) in its assessment of potential environmental effects resulting from conservation activities in commercial buildings. 76 refs., 2 figs., 19 tabs.

  2. High resolution dynamical downscaling of air temperature and relative humidity: performance assessment of WRF for Portugal

    Science.gov (United States)

    Menezes, Isilda; Pereira, Mário; Moreira, Demerval; Carvalheiro, Luís; Bugalho, Lourdes; Corte-Real, João

    2017-04-01

    Air temperature and relative humidity are two of the atmospheric variables with higher impact on human and natural systems, contributing to define the stress/comfortable conditions, affecting the productivity and health of the individuals as well as diminishing the resilience to other environmental hazards. Atmospheric regional models, driven by large scale forecasts from global circulation models, are the best way to reproduce such environmental conditions in high space-time resolution. This study is focused on the performance assessment of the WRF mesoscale model to perform high resolution dynamical downscaling for Portugal with three two-way nested grids, at 60 km, 20 km and 5 km horizontal resolution. The simulations of WRF models were produced with different initial and boundary forcing conditions. The NCEP-FNL Operational Global Analysis data available on 1-degree by 1-degree grid every six hours and ERA-Interim reanalyses dataset were used to drive the models. Two alternative configurations of the WRF model, including planetary boundary, layer schemes, microphysics, land-surface models, radiation schemes, were used and tested within the 5 km spatial resolution domain. Simulations of air temperature and relative humidity were produced for January and July of 2016 and compared with the observed datasets provided by the Instituto Português do Mar e da Atmosfera (IPMA) for 83 weather stations. Different performance measures of bias, precision, and accuracy were used, namely normalized bias, standard deviation, mean absolute error, root mean square error, bias of root mean square error as well as correlation based measures (e.g., coefficient of determination) and goodness of fit measures (index of agreement). Main conclusions from the obtained results reveal: (i) great similarity between the spatial patterns of the simulated and observed fields; (ii) only small differences between simulations produced with ERA-Interim and NCEP-FNL, in spite of some differences

  3. Temperature-related mortality estimates after accounting for the cumulative effects of air pollution in an urban area.

    Science.gov (United States)

    Stanišić Stojić, Svetlana; Stanišić, Nemanja; Stojić, Andreja

    2016-07-11

    To propose a new method for including the cumulative mid-term effects of air pollution in the traditional Poisson regression model and compare the temperature-related mortality risk estimates, before and after including air pollution data. The analysis comprised a total of 56,920 residents aged 65 years or older who died from circulatory and respiratory diseases in Belgrade, Serbia, and daily mean PM10, NO2, SO2 and soot concentrations obtained for the period 2009-2014. After accounting for the cumulative effects of air pollutants, the risk associated with cold temperatures was significantly lower and the overall temperature-attributable risk decreased from 8.80 to 3.00 %. Furthermore, the optimum range of temperature, within which no excess temperature-related mortality is expected to occur, was very broad, between -5 and 21 °C, which differs from the previous findings that most of the attributable deaths were associated with mild temperatures. These results suggest that, in polluted areas of developing countries, most of the mortality risk, previously attributed to cold temperatures, can be explained by the mid-term effects of air pollution. The results also showed that the estimated relative importance of PM10 was the smallest of four examined pollutant species, and thus, including PM10 data only is clearly not the most effective way to control for the effects of air pollution.

  4. [Biological contamination in office buildings related to ventilation/air conditioning system].

    Science.gov (United States)

    Bródka, Karolina; Sowiak, Małgorzata; Kozajda, Anna; Cyprowski, Marcin; Irena, Szadkowska-Stańczyk

    2012-01-01

    Indoor air is contaminated with microorganisms coming from both the atmospheric air and sources present in premises. The aim of this study was to analyze the concentrations of biological agents in office buildings, dependending on ventilation/air conditioning system and season. The study covered office buildings (different in the system of ventila-tion/air conditioning). Air samples for assessing the levels of inhalable dust, endotoxins and (1-->3)-beta-D-glucans, were taken at the selected stationary points of each building during summer and winter. The air was sampled for 6 h, using portable sets consisting of the GilAir 5 pump and the head filled with a filter of fiber glass. The samples for the presence of airborne bacteria and fungi were collected twice during the day using the impaction method. Average concentrations of inhalable dust, bacteria, fungi, endotoxins and (1-->3)-beta-D-glucans in office premises were 0.09 mg/m3, 6.00 x 10(2) cfu/m3, 4.59 x 10(1) cfu/m3, 0.42 ng/m3 and 3.91 ng/m3, respectively. Higher concentrations of the investigated agents were found in summer. In premises with air conditioning concentrations of airborne fungi, (1-->3)-beta-D-glucans and inhalable dust were significantly lower in winter. In summer the trend was reverse except for (1-->3)-beta-D-glucans. Concentrations of biological agents were affected by the season and the presence of air conditioning. Concentrations of inhalable dust, bacteria, fungi, endotoxins and (1-->3)-beta-D-glucans, observed inside the office buildings, were significantly higher in summer than in winter. The presence of the air conditioning system modified in various ways the levels of biological agents. Its influence was greater on the concentration of fungi and (1-->3)-beta-D-glucans than on that of bacteria and endotoxins.

  5. Traffic-related Air Pollution, Lung Function, and Host Vulnerability. New Insights from the PARIS Birth Cohort.

    Science.gov (United States)

    Bougas, Nicolas; Rancière, Fanny; Beydon, Nicole; Viola, Malika; Perrot, Xavier; Gabet, Stephan; Lezmi, Guillaume; Amat, Flore; De Blic, Jacques; Just, Jocelyne; Momas, Isabelle

    2018-05-01

    Although the effects of traffic-related air pollution on respiratory exacerbations have been well documented, its impact on lung function in childhood remains unclear. Our aim was to investigate the associations of prenatal, early, and lifetime traffic-related air pollution exposure with lung function at 8-9 years studying possible effect modification by sex, sensitization at 8-9 years, and early lower respiratory tract infections. We conducted this study among 788 children from the PARIS (Pollution and Asthma Risk: an Infant Study) birth cohort. Lung function tests were performed during the medical examination at 8-9 years. Traffic-related air pollution exposure during each trimester of pregnancy was estimated using nitrogen oxides background measurements. Postnatal traffic-related air pollution exposure was assessed by a nitrogen oxides air dispersion model at both residential and daycare/school addresses. Associations between lung function and traffic-related air pollution exposure were analyzed by multiple linear regression models. Higher prenatal nitrogen oxides levels, especially during the second trimester of pregnancy, were associated with a lower forced expiratory flow at 25-75% of the forced vital capacity, but there were no significant associations between prenatal nitrogen oxide levels and forced vital capacity, forced expiratory volume during 1 second, or the forced expiratory volume during 1 second/forced vital capacity ratio overall. Postnatal traffic-related air pollution exposure was associated with lower lung function among children with early lower respiratory tract infections or sensitization at 8-9 years, but not in the full cohort. In children with early repeated lower respiratory tract infections, an interquartile increase in lifetime nitrogen oxides exposure was associated with both a lower forced expiratory volume during 1 second (-62.6 ml; 95% confidence interval = -107.0 to -18.1) and forced vital capacity (-55.7 ml; 95% confidence

  6. Interpreting Mobile and Handheld Air Sensor Readings in Relation to Air Quality Standards and Health Effect Reference Values: Tackling the Challenges

    Directory of Open Access Journals (Sweden)

    George M. Woodall

    2017-09-01

    Full Text Available The US Environmental Protection Agency (EPA and other federal agencies face a number of challenges in interpreting and reconciling short-duration (seconds to minutes readings from mobile and handheld air sensors with the longer duration averages (hours to days associated with the National Ambient Air Quality Standards (NAAQS for the criteria pollutants-particulate matter (PM, ozone, carbon monoxide, lead, nitrogen oxides, and sulfur oxides. Similar issues are equally relevant to the hazardous air pollutants (HAPs where chemical-specific health effect reference values are the best indicators of exposure limits; values which are often based on a lifetime of continuous exposure. A multi-agency, staff-level Air Sensors Health Group (ASHG was convened in 2013. ASHG represents a multi-institutional collaboration of Federal agencies devoted to discovery and discussion of sensor technologies, interpretation of sensor data, defining the state of sensor-related science across each institution, and provides consultation on how sensors might effectively be used to meet a wide range of research and decision support needs. ASHG focuses on several fronts: improving the understanding of what hand-held sensor technologies may be able to deliver; communicating what hand-held sensor readings can provide to a number of audiences; the challenges of how to integrate data generated by multiple entities using new and unproven technologies; and defining best practices in communicating health-related messages to various audiences. This review summarizes the challenges, successes, and promising tools of those initial ASHG efforts and Federal agency progress on crafting similar products for use with other NAAQS pollutants and the HAPs. NOTE: The opinions expressed are those of the authors and do not necessary represent the opinions of their Federal Agencies or the US Government. Mention of product names does not constitute endorsement.

  7. The burden of ischemic heart disease related to ambient air pollution exposure in a coastal city in South China.

    Science.gov (United States)

    Huang, Jing; Li, Guoxing; Qian, Xujun; Xu, Guozhang; Zhao, Yan; Huang, Jian; Liu, Qichen; He, Tianfeng; Guo, Xinbiao

    2018-07-01

    Air pollution is considered one of the most important risk factors for ischemic heart disease (IHD), which is a major public health concern. The disease burden of IHD has continued to rise in China in the past two decades. However, epidemiological studies examining the associations between air pollution and IHD have been scarce in China, and the only studies were conducted in severe air pollution areas, where air pollution levels seriously exceed the World Health Organization Air Quality Guidelines. Whether the influence of air pollution on IHD in areas with relatively low levels of air pollution differs from the influence of high pollution levels in heavily studied areas was unknown until now. Furthermore, the estimation of the disease burden of IHD related to air pollution has been very limited. We conducted a time-series study to estimate the short-term burden of ambient air pollution on IHD using the indicator of years of life lost (YLL), based on 10 322 IHD deaths from 2011 to 2015 in Ningbo, a coastal city in South China. The mean concentrations of fine particle (PM 2.5 ), sulfur dioxide (SO 2 ) and nitrogen dioxide (NO 2 ) were 49.58 μg/m 3 , 21.34 μg/m 3 and 43.41 μg/m 3 , respectively. A 10 μg/m 3 increase in PM 2.5 , SO 2 and NO 2 was associated with changes in YLL of 0.71 (95%CI: - 0.21,1.64), 3.31 (95%CI: 0.78, 5.84), and 2.27 (95%CI: 0.26, 4.28) years, respectively. Relatively stronger impacts were found for gaseous pollutants than PM 2.5 . A larger increase in YLL was found in the younger population than in the older population for NO 2 exposure. In addition, estimations of the effects of SO 2 and NO 2 on YLL were higher for males than females. SO 2 exposure was positively associated with YLL in widowed group. The findings highlighted the importance of stringent air pollution control, especially for gaseous pollutants. Furthermore, using the indicator of YLL, considering the occurrence of death at different ages, provided more

  8. War-related stressors as predictors of post-deployment health of Air Force women.

    Science.gov (United States)

    Pierce, Penny F; Lewandowski-Romps, Lisa; Silverschanz, Perry

    2011-01-01

    Little is known about the effects of combat exposure on women's health after service in Operation Iraqi Freedom (OIF). Our purpose was to describe the incidence and nature of physical heath symptoms reported by deployed women to identify problematic areas where early intervention or better surveillance might be directed. Using a random, stratified sample (theater vs. non-theater; parent vs. non-parent; and military component including active, guard, and reserve members) of 1,114 Air Force women, we provide descriptive statistics, group comparisons, and multiple regression models to identify health concerns and potential predictors of physical health outcomes. Findings revealed that those in the reserve/guard forces (vs. active duty) and those in the theater of operations (vs. elsewhere during the same time period) reported greater physical health problems (β = -0.07, p social functioning (β = 0.08, p war-related predictors of health among women serving in deployed locations around the world. Copyright © 2011. Published by Elsevier Inc.

  9. Urban air pollution in school-related microenvironments in Bogota, Colombia

    Directory of Open Access Journals (Sweden)

    Juan Felipe Franco

    2013-05-01

    Full Text Available Particle-related pollution (PM10, PM2.5 and soot was measured in both indoor and outdoor microenvironments at four public elementary schools in Bogota, Colombia. Three of these schools were located alongside major urban roads in which different types of public transit systems are used (bus rapid transit system and conventional transit buses. The fourth school was located on a non-congested road (background school. Pollutant levels at schools situated on major-roads were higher than those found at the low-congestion-road school. Outdoor black carbon daily mean concentrations at the schools located near major roads were up to six times higher than those recorded at the background school. Mean particulate matter concentrations at schools near major roads were above international standards, suggesting that school-age children in Bogota are exposed to pollution levels that are considered to be harmful by environmental and public health authorities. Elevated indoor and outdoor pollutant concentrations documented in this study suggested that traffic has a direct impact on air quality regarding the schools’ characterised microenvironments.

  10. Regionally differentiated air pollution control regulations in the installation-related emission control law of the Federal Republic of Germany

    International Nuclear Information System (INIS)

    Buettner, T.W.

    1992-01-01

    The volume treats an issue from the boundary zone between environmental law and environmental economics, namely the regionalization of air pollution control standards in installation-related emission control law. In order to examine the question of whether this proposal, which originates in the field of environmental economics, can be adopted and is purposeful, the author initially performs a complete inventorization of applicable norms, this covering emission control law, the law of regional planning, and the provisions of international law. This status quo is then reviewed using conformity and optimization criteria developed by the political sciences. The assessment comes to the conclusion that the introduction of regionally differentiated air pollution control standards is not desirable. The author further submits proposals for the streamlining of the law of installation-related air pollution control in the Federal Republic of Germany. (orig.) [de

  11. Relation of air pollution with epidemiology of respiratory diseases in isfahan, Iran from 2005 to 2009

    Directory of Open Access Journals (Sweden)

    Maasoumeh Rashidi

    2013-01-01

    Full Text Available Background: National Institute of Environmental Health Sciences (NIEHS scientists shows that long-term exposure to air pollutants increases the risk of respiratory diseases such as allergies, asthma, chronic obstructive pulmonary disease, and lung cancer. Children and the elderly are particularly vulnerable to the health effects of ozone, fine particles, and other airborne toxicants. Air pollution factors are considered as one of the underlying causes of respiratory diseases. This study aimed to determine the association of respiratory diseases documented in medical records and air pollution (Map distribution of accumulation in Isfahan province, Iran. By plotting the prevalence and spatial distribution maps, important differences from different points can be observed. Materials and Methods: The geographic information system (GIS, pollutant standards index (PSI measurements, and remote Sensing (RS technology were used after entering data in the mapping information table; spatial distribution was mapped and distribution of Geographical Epidemiology of Respiratory Diseases in Isfahan province (Iran was determined in this case study from 2005 to 2009. Results: Space with tracing the distribution of respiratory diseases was scattered based on the distribution of air pollution in the points is an important part of this type of diseases in Isfahan province where air pollution was more abundant. Conclusion: The findings of this study emphasis on the importance of preventing the exposure to air pollution, and to control air pollution product industries, to improve work environmental health, and to increase the health professionals and public knowledge in this regard.

  12. Relation of air pollution with epidemiology of respiratory diseases in isfahan, Iran from 2005 to 2009.

    Science.gov (United States)

    Rashidi, Maasoumeh; Ramesht, Mohammad Hossein; Zohary, Moein; Poursafa, Parinaz; Kelishadi, Roya; Rashidi, Zeinab; Rouzbahani, Reza

    2013-12-01

    National Institute of Environmental Health Sciences (NIEHS) scientists shows that long-term exposure to air pollutants increases the risk of respiratory diseases such as allergies, asthma, chronic obstructive pulmonary disease, and lung cancer. Children and the elderly are particularly vulnerable to the health effects of ozone, fine particles, and other airborne toxicants. Air pollution factors are considered as one of the underlying causes of respiratory diseases. This study aimed to determine the association of respiratory diseases documented in medical records and air pollution (Map distribution) of accumulation in Isfahan province, Iran. By plotting the prevalence and spatial distribution maps, important differences from different points can be observed. The geographic information system (GIS), pollutant standards index (PSI) measurements, and remote Sensing (RS) technology were used after entering data in the mapping information table; spatial distribution was mapped and distribution of Geographical Epidemiology of Respiratory Diseases in Isfahan province (Iran) was determined in this case study from 2005 to 2009. Space with tracing the distribution of respiratory diseases was scattered based on the distribution of air pollution in the points is an important part of this type of diseases in Isfahan province where air pollution was more abundant. The findings of this study emphasis on the importance of preventing the exposure to air pollution, and to control air pollution product industries, to improve work environmental health, and to increase the health professionals and public knowledge in this regard.

  13. Relations between Air-Fuel Ratio and Dynamic Performance of Small Race Cars

    OpenAIRE

    位田, 晴良; Ida, Haruyoshi; 漁, 佑一郎; Sunadori, Yuichiro; 牧田, 俊太郎; Makita, Syuntaro; 宮﨑, 真央; Miyazaki, Manaka; 磯松, 弥司; Isomatsu, Yatsuka

    2017-01-01

    'It goes without saying that engine output power characteristics greatly affect the dynamic performance of the race car. One of the methods of changing the output power of the engine is to adjust the set amount of fuel supply. This method changes the air-fuel ratio of the air fuel mixture supplied to the engine. In this study, a slalom test run of a small race car was used to examine dynamic performance with attention to the air-fuel ratio changed by adjusting the set amount of fuel supply. T...

  14. Traffic-related air pollution and noise and children's blood pressure: results from the PIAMA birth cohort study.

    Science.gov (United States)

    Bilenko, Natalya; van Rossem, Lenie; Brunekreef, Bert; Beelen, Rob; Eeftens, Marloes; Hoek, Gerard; Houthuijs, Danny; de Jongste, Johan C; van Kempen, Elise; Koppelman, Gerard H; Meliefste, Kees; Oldenwening, Marieke; Smit, Henriette A; Wijga, Alet H; Gehring, Ulrike

    2015-01-01

    Elevation of a child's blood pressure may cause possible health risks in later life. There is evidence for adverse effects of exposure to air pollution and noise on blood pressure in adults. Little is known about these associations in children. We investigated the associations of air pollution and noise exposure with blood pressure in 12-year-olds. Blood pressure was measured at age 12 years in 1432 participants of the PIAMA birth cohort study. Annual average exposure to traffic-related air pollution [NO2, mass concentrations of particulate matter with diameters of less than 2.5 µm (PM2.5) and less than 10 µm (PM10), and PM2.5 absorbance] at the participants' home and school addresses at the time of blood pressure measurements was estimated by land-use regression models. Air pollution exposure on the days preceding blood pressure measurements was estimated from routine air monitoring data. Long-term noise exposure was assessed by linking addresses to modelled equivalent road traffic noise levels. Associations of exposures with blood pressure were analysed by linear regression. Effects are presented for an interquartile range increase in exposure. Long-term exposure to NO2 and PM2.5 absorbance were associated with increased diastolic blood pressure, in children who lived at the same address since birth [adjusted mean difference (95% confidence interval) [mmHg] 0.83 (0.06 to 1.61) and 0.75 (-0.08 to 1.58), respectively], but not with systolic blood pressure. We found no association of blood pressure with short-term air pollution or noise exposure. Long-term exposure to traffic-related air pollution may increase diastolic blood pressure in children. © The European Society of Cardiology 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  15. Results of calculations of external gamma radiation exposure rates from local fallout and the related radionuclide compositions of two hypothetical 1-MT nuclear bursts. Final report

    International Nuclear Information System (INIS)

    Hicks, H.

    1984-12-01

    This report presents data on calculated gamma radiation exposure rates and local surface deposition of related radionuclides resulting from two hypothetical 1-Mt nuclear bursts. Calculations are made of the debris from two types of bombs: one containing 235 U as a fissionable material (designated oralloy), the other containing 238 U (designated tuballoy). 4 references

  16. Applied research on air pollution using nuclear-related analytical techniques. Report on the second research co-ordination meeting

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    A co-ordinated research programme (CRP) on applied research on air pollution using nuclear-related techniques is a global CRP which started in 1992, and is scheduled to run until early 1997. The purpose of this CRP is to promote the use of nuclear analytical techniques in air pollution studies, e.g. NAA, XRF, and PIXE for the analysis of toxic and other trace elements in air particulate matter. The main purposes of the core programme are i) to support the use of nuclear and nuclear-related analytical techniques for research and monitoring studies on air pollution, ii) to identify major sources of air pollution affecting each of the participating countries with particular reference to toxic heavy metals, and iii) to obtain comparative data on pollution levels in areas of high pollution (e.g. a city centre or a populated area downwind of a large pollution source) and low pollution (e.g. rural area). This document reports the discussions held during the second Research Co-ordination Meeting (RCM) for the CRP which took place at ANSTO in Menai, Australia. (author)

  17. Applied research on air pollution using nuclear-related analytical techniques. Report on the second research co-ordination meeting

    International Nuclear Information System (INIS)

    1995-01-01

    A co-ordinated research programme (CRP) on applied research on air pollution using nuclear-related techniques is a global CRP which started in 1992, and is scheduled to run until early 1997. The purpose of this CRP is to promote the use of nuclear analytical techniques in air pollution studies, e.g. NAA, XRF, and PIXE for the analysis of toxic and other trace elements in air particulate matter. The main purposes of the core programme are i) to support the use of nuclear and nuclear-related analytical techniques for research and monitoring studies on air pollution, ii) to identify major sources of air pollution affecting each of the participating countries with particular reference to toxic heavy metals, and iii) to obtain comparative data on pollution levels in areas of high pollution (e.g. a city centre or a populated area downwind of a large pollution source) and low pollution (e.g. rural area). This document reports the discussions held during the second Research Co-ordination Meeting (RCM) for the CRP which took place at ANSTO in Menai, Australia. (author)

  18. 'Green' on the ground but not in the air: Pro-environmental attitudes are related to household behaviours but not discretionary air travel.

    Science.gov (United States)

    Alcock, Ian; White, Mathew P; Taylor, Tim; Coldwell, Deborah F; Gribble, Matthew O; Evans, Karl L; Corner, Adam; Vardoulakis, Sotiris; Fleming, Lora E

    2017-01-01

    The rise in greenhouse gas emissions from air travel could be reduced by individuals voluntarily abstaining from, or reducing, flights for leisure and recreational purposes. In theory, we might expect that people with pro-environmental value orientations and concerns about the risks of climate change, and those who engage in more pro-environmental household behaviours, would also be more likely to abstain from such voluntary air travel, or at least to fly less far. Analysis of two large datasets from the United Kingdom, weighted to be representative of the whole population, tested these associations. Using zero-inflated Poisson regression models, we found that, after accounting for potential confounders, there was no association between individuals' environmental attitudes, concern over climate change, or their routine pro-environmental household behaviours, and either their propensity to take non-work related flights, or the distances flown by those who do so. These findings contrasted with those for pro-environmental household behaviours, where associations with environmental attitudes and concern were observed. Our results offer little encouragement for policies aiming to reduce discretionary air travel through pro-environmental advocacy, or through 'spill-over' from interventions to improve environmental impacts of household routines.

  19. ‘Green’ on the ground but not in the air: Pro-environmental attitudes are related to household behaviours but not discretionary air travel

    Science.gov (United States)

    White, Mathew P.; Taylor, Tim; Coldwell, Deborah F.; Gribble, Matthew O.; Evans, Karl L.; Corner, Adam; Vardoulakis, Sotiris; Fleming, Lora E.

    2017-01-01

    The rise in greenhouse gas emissions from air travel could be reduced by individuals voluntarily abstaining from, or reducing, flights for leisure and recreational purposes. In theory, we might expect that people with pro-environmental value orientations and concerns about the risks of climate change, and those who engage in more pro-environmental household behaviours, would also be more likely to abstain from such voluntary air travel, or at least to fly less far. Analysis of two large datasets from the United Kingdom, weighted to be representative of the whole population, tested these associations. Using zero-inflated Poisson regression models, we found that, after accounting for potential confounders, there was no association between individuals' environmental attitudes, concern over climate change, or their routine pro-environmental household behaviours, and either their propensity to take non-work related flights, or the distances flown by those who do so. These findings contrasted with those for pro-environmental household behaviours, where associations with environmental attitudes and concern were observed. Our results offer little encouragement for policies aiming to reduce discretionary air travel through pro-environmental advocacy, or through ‘spill-over’ from interventions to improve environmental impacts of household routines. PMID:28367001

  20. SPECIAL ISSUE OF THE JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION ON THE PARTICULATE MATTER SUPERSITES PROGRAM AND RELATED STUDIES

    Science.gov (United States)

    This article is the preface or editors note to the dedicated issue of the Journal of the Air & Waste Management Association for a selection of scientific papers from the specialty conference entitled, "Particulate Matter Supersites Program and Related Studies," that was...

  1. Traffic-Related air pollution, noise at school, and behavioral problems in barcelona schoolchildren: A cross-sectional study

    NARCIS (Netherlands)

    J. Forns (Joan); P. Dadvand (Payam); M. Foraster (Maria); M. Alvarez-Pedrerol (Mar); I. Rivas (Ioar); M. López-Vicente (Mònica); E. Suades-González (Elisabet); R. Garcia-Esteban (Raquel); M. Esnaola (Mikel); M. Cirach (Marta); J. Grellier (James); X. Basagaña (Xavier); X. Querol (Xavier); M. Guxens Junyent (Mònica); M. Nieuwenhuijsen (Mark); J. Sunyer (Jordi)

    2016-01-01

    textabstractBackground: The available evidence of the effects of air pollution and noise on behavioral development is limited, and it overlooks exposure at schools, where children spend a considerable amount of time. Objective: We aimed to investigate the associations of exposure to traffic-related

  2. Dynamics of spatial heterogeneity of stomatal closure in Tradescantia virginiana altered by growth at high relative air humidity

    NARCIS (Netherlands)

    Rezaei Nejad, A.; Harbinson, J.; Meeteren, van U.

    2006-01-01

    The spatial heterogeneity of stomatal closure in response to rapid desiccation of excised well-watered Tradescantia virginiana leaves grown at moderate (55%) or high (90%) relative air humidity (RH) was studied using a chlorophyll fluorescence imaging system under non-photorespiratory conditions.

  3. (Un)Healthy in the city : Adverse health effects of traffic-related noise and air pollution

    NARCIS (Netherlands)

    Zijlema, Wilma

    2016-01-01

    We investigated the adverse health effects of urbanity, traffic-related noise and air pollution. We used harmonized data from multiple European cohort studies: LifeLines, HUNT, FINRISK, EPIC-Oxford and KORA. Based on our studies, we concluded that the living environment may be associated with

  4. Traffic-related air pollutants induce the release of allergen-containing cytoplasmic granules from grass pollen.

    NARCIS (Netherlands)

    Motta, A C; Marliere, M; Peltre, G; Sterenberg, P A; Lacroix, G

    2006-01-01

    BACKGROUND/AIM: Pollen cytoplasmic granules (PCG) are loaded with allergens. They are released from grass pollen grains following contact with water and can form a respirable allergenic aerosol. On the other hand, the traffic-related air pollutants NO2 and O3 are known to be involved in the current

  5. Traffic-related air pollutants induce the release of allergen-containing cytoplasmic granules from grass pollen

    NARCIS (Netherlands)

    Motta, AC; Marliere, M; Peltre, G; Sterenberg, PA; Lacroix, G

    2006-01-01

    Background/Aim: Pollen cytoplasmic granules (PCG) are loaded with allergens. They are released from grass pollen grains following contact with water and can form a respirable allergenic aerosol. On the other hand, the traffic-related air pollutants NO2 and O-3 are known to be involved in the current

  6. Calculation of Relative Binding Free Energy in the Water-Filled Active Site of Oligopeptide-Binding Protein A.

    Science.gov (United States)

    Maurer, Manuela; de Beer, Stephanie B A; Oostenbrink, Chris

    2016-04-15

    The periplasmic oligopeptide binding protein A (OppA) represents a well-known example of water-mediated protein-ligand interactions. Here, we perform free-energy calculations for three different ligands binding to OppA, using a thermodynamic integration approach. The tripeptide ligands share a high structural similarity (all have the sequence KXK), but their experimentally-determined binding free energies differ remarkably. Thermodynamic cycles were constructed for the ligands, and simulations conducted in the bound and (freely solvated) unbound states. In the unbound state, it was observed that the difference in conformational freedom between alanine and glycine leads to a surprisingly slow convergence, despite their chemical similarity. This could be overcome by increasing the softness parameter during alchemical transformations. Discrepancies remained in the bound state however, when comparing independent simulations of the three ligands. These difficulties could be traced to a slow relaxation of the water network within the active site. Fluctuations in the number of water molecules residing in the binding cavity occur mostly on a timescale larger than the simulation time along the alchemical path. After extensive simulations, relative binding free energies that were converged to within thermal noise could be obtained, which agree well with available experimental data.

  7. Application of genomic densitometry for calculating the relative population of Escherichia Coli in the intestine of broiler chicks

    Directory of Open Access Journals (Sweden)

    A.R Seidavi

    2009-05-01

    Full Text Available In this study, the densitometry technique for calculating of the relative population of Escherichia coli in various segments of the intestine of broiler chicks was evaluated. Following preparation of the intestinal contents, the process of extraction and purification of DNA from the contents of duodenum, jejunum, ileum and cecum was undertaken. A specific polymerase chain reaction (PCR using two pairs of primers was employed to detect Escherichia coli and total bacteria present in the gastrointestinal tract of the chicks. Specific bands of E.coli were obtained using densitometry and Gel Proc Analyzer software based on linear regression with extrapolation. E.coli populations at different ages were also determined in various segments of the gastrointestinal tract of the chicks. The Results of this experiment indicated that 0.000004%, 0.07%, 0.64% and 2.51% of total bacteria present in the duodenum, jejunum, ileum and cecum respectively consisted of E.coli. Also, E.coli constitutes 1.76, 0.01 and 0.80% of the total intestinal bacteria of chicks at 4, 14 and 30 days of age respectively. Furthermore, it was shown that at 4 days of age, 0.30, 2.05 and 3.97% of the total bacteria present in the jejunum, ileum and cecum respectively were from E.coli species and this bacteria was absent in the duodenum. At 14 days of age these figures were 0.000009%, 0.00011% and 0.08% respectively while at 30 days of age 0.00011%, 0.009% and 2.40% of all bacteria in the duodenum, ileum and cecum were E.coli species and this bacteria was absent in the jejunum. In conclusion, the densitometry method based on PCR results can be regarded as a useful tool for densitometry the relative population E.coli in the gastrointestinal tract of poultry.

  8. Comparative Studies on Vehicle Related Policies for Air Pollution Reduction in Ten Asian Countries

    Directory of Open Access Journals (Sweden)

    Keiko Hirota

    2010-01-01

    Full Text Available Asian countries are facing major air pollution problems due to rapid economic growth, urbanization and motorization. Mortality and respiratory diseases caused by air pollution are believed to be endemic in major cities of these countries. Regulations and standards are the first requirement for reducing emissions from both fixed and mobile sources. This paper emphasizes monitoring problems such as vehicle registration systems, inspection and maintenance (I/M systems and fuel quality monitoring systems for vehicles in use. Monitoring problems in developing countries share similar characteristics such as a weakness in government initiatives and inadequate operation of government agencies, which results from a lack of human resources and availability of adequate facilities. Finally, this paper proposes a method to assure air quality improvements under the different shares of emission regulations in these Asian countries and introduces an example of an evaluation method based on a policy survey to improve air quality.

  9. Long-Term Exposure to Traffic-Related Air Pollution and Risk of Incident Atrial Fibrillation

    DEFF Research Database (Denmark)

    Monrad, Maria; Sajadieh, Ahmad; Christensen, Jeppe Schultz

    2017-01-01

    BACKGROUND: Atrial fibrillation is the most common sustained arrhythmia and associated with cardiovascular morbidity and mortality. The few studies conducted on short-term effects of air pollution on episodes of atrial fibrillation indicates a positive association, though not consistently...

  10. Results of calculations of external gamma radiation exposure rates from fallout and the related radionuclide compositions. Operation Tumbler-Snapper, 1952

    International Nuclear Information System (INIS)

    Hicks, H.G.

    1981-07-01

    This report presents data on calculated gamma radiation exposure rates and ground deposition of related radionuclides resulting from Events that deposited detectable radioactivity outside the Nevada Test Site complex

  11. Air pollution-related health and climate benefits of clean cookstove programs in Mozambique

    Science.gov (United States)

    Anenberg, Susan C.; Henze, Daven K.; Lacey, Forrest; Irfan, Ans; Kinney, Patrick; Kleiman, Gary; Pillarisetti, Ajay

    2017-02-01

    Approximately 95% of households in Mozambique burn solid fuels for cooking, contributing to elevated indoor and outdoor fine particulate matter (PM2.5) concentrations and subsequent health and climate impacts. Little is known about the potential health and climate benefits of various approaches for expanding the use of cleaner stoves and fuels in Mozambique. We use state-of-the-science methods to provide a first-order estimation of potential air pollution-related health and climate benefits of four illustrative scenarios in which traditional cooking fires and stoves are displaced by cleaner and more efficient technologies. For rural areas, we find that a 10% increase in the number of households using forced draft wood-burning stoves could achieve >2.5 times more health benefits from reduced PM2.5 exposure (200 avoided premature deaths and 14 000 avoided disability adjusted life years, DALYs, over a three-year project lifetime) compared to natural draft stoves in the same households, assuming 70% of households use the new technology for both cases. Expanding use of LPG stoves to 10% of households in five major cities is estimated to avoid 160 premature deaths and 11 000 DALYs from reduced PM2.5 exposure for a three-year intervention, assuming 60% of households use the new stove. Advanced charcoal stoves would achieve ∽80% of the PM2.5-related health benefits of LPG stoves. Approximately 2%-5% additional health benefits would result from reduced ambient PM2.5, depending on the scenario. Although climate impacts are uncertain, we estimate that all scenarios would reduce expected climate change-related temperature increases from continued solid fuel use by 4%-6% over the next century. All results are based on an assumed adjustment factor of 0.8 to convert from laboratory-based emission reduction measurements to exposure reductions, which could be optimistic in reality given potential for continued use of the traditional stove. We conclude that cleaner cooking stoves

  12. Relation Between Bitumen Content and Percentage Air Voids in Semi Dense Bituminous Concrete

    Science.gov (United States)

    Panda, R. P.; Das, Sudhanshu Sekhar; Sahoo, P. K.

    2018-06-01

    Hot mix asphalt (HMA) is a heterogeneous mix of aggregate, mineral filler, bitumen, additives and air voids. Researchers have indicated that the durability of the HMA is sensitive on the actual bitumen content and percentage air void. This paper aims at establishing the relationship between the bitumen content and the percentage air voids in Semi Dense Bituminous Concrete (SDBC) using Viscosity Grade-30 (VG-30) bitumen. Total 54 samples have been collected, for formulation and validation of relationship and observed that the percentage air voids increases with decrease in actual bitumen content and vice versa. A minor increase in percentage air voids beyond practice of designed air voids in Marshall Method of design is required for better performance, indicating a need for reducing the codal provision of minimum bitumen content for SDBC as specified in Specification for Road & Bridges (Fourth Revision) published by Indian Road Congress, 2001. The study shows a possibility of reducing designed minimum bitumen content from codal provision for SDBC by 0.2% of weight with VG-30 grade of Bitumen.

  13. Relation Between Bitumen Content and Percentage Air Voids in Semi Dense Bituminous Concrete

    Science.gov (United States)

    Panda, R. P.; Das, Sudhanshu Sekhar; Sahoo, P. K.

    2018-02-01

    Hot mix asphalt (HMA) is a heterogeneous mix of aggregate, mineral filler, bitumen, additives and air voids. Researchers have indicated that the durability of the HMA is sensitive on the actual bitumen content and percentage air void. This paper aims at establishing the relationship between the bitumen content and the percentage air voids in Semi Dense Bituminous Concrete (SDBC) using Viscosity Grade-30 (VG-30) bitumen. Total 54 samples have been collected, for formulation and validation of relationship and observed that the percentage air voids increases with decrease in actual bitumen content and vice versa. A minor increase in percentage air voids beyond practice of designed air voids in Marshall Method of design is required for better performance, indicating a need for reducing the codal provision of minimum bitumen content for SDBC as specified in Specification for Road & Bridges (Fourth Revision) published by Indian Road Congress, 2001. The study shows a possibility of reducing designed minimum bitumen content from codal provision for SDBC by 0.2% of weight with VG-30 grade of Bitumen.

  14. Acute symptoms related to air pollution in urban areas: a study protocol

    Directory of Open Access Journals (Sweden)

    Forouzanfar Mohammad

    2006-08-01

    Full Text Available Abstract Background The harmful effects of urban air pollution on general population in terms of annoying symptoms are not adequately evaluated. This is in contrast to the hospital admissions and short term mortality. The present study protocol is designed to assess the association between the level of exposure to certain ambient air pollutants and a wide range of relevant symptoms. Awareness of the impact of pollution on the population at large will make our estimates of the pertinent covert burden imposed on the society more accurate. Methods/design A cross sectional study with spatial analysis for the addresses of the participants was conducted. Data were collected via telephone interviews administered to a representative sample of civilians over age four in the city. Households were selected using random digit dialling procedures and randomization within each household was also performed to select the person to be interviewed. Levels of exposure are quantified by extrapolating the addresses of the study population over the air pollution matrix of the city at the time of the interview and also for different lag times. This information system uses the data from multiple air pollution monitoring stations in conjunction with meteorological data. General linear models are applied for statistical analysis. Discussion The important limitations of cross-sectional studies on acute effects of air pollution are personal confounders and measurement error for exposure. A wide range of confounders in this study are controlled for in the statistical analysis. Exposure error may be minimised by employing a validated geographical information system that provides accurate estimates and getting detailed information on locations of individual participants during the day. The widespread operation of open air conditioning systems in the target urban area which brings about excellent mixing of the outdoor and indoor air increases the validity of outdoor pollutants

  15. Assessment of indoor air quality related to potential vapor intrusion: Issues for former manufactured gas plants

    International Nuclear Information System (INIS)

    Rames, Antoine; Guillossou, Gaelle; Ronga-Pezeret, Sylvaine; Hulot, Corinne

    2012-01-01

    The indoor air quality of buildings on sites with soil or groundwater contaminated with volatile or semi-volatile compounds can be degraded by potential vapor intrusion (VI) from these environmental media. For sites of former manufactured gas plants (MGP), the compounds that must be considered are BTEX (benzene, toluene, ethylbenzene, and xylenes), 8 of the 16 polycyclic aromatic hydrocarbons (PAHs) generally studied, and, to a lesser degree, phenol and hydrogen cyanide. Given the plausibility of VI and in accordance with current recommendations of the French Ministry of the Environment, measurements of indoor air quality (and outdoor air, for additional analyses) were conducted on two occasions during the winter and summer of 2010. These measurements simultaneously used multiple air sampling devices (Summa canisters, Gore modules, air pumps coupled to various matrices; such as XAD2, silica gel, etc.). Phenol and hydrogen cyanide have not previously been quantified (limit of quantification between 0.12 and 2.00 μg/m 3 ). BTEX and PAHs were found ubiquitously at concentrations on the order of 1 to 10 μg/m 3 for BTEX and naphthalene and one to ten ng/m 3 for PAHs other than naphthalene) at all 14 MGP and both control sites, regardless of where onsite the air was sampled (office, basement or crawl space, or outdoors). These levels (the maximum considered) do not allow us to conclude that the indoor air is degraded according to the official French guidelines for managing potentially contaminated sites and soils. Thus, no excess health risk is expected for residents of these sites because of exposure to possible VI, which cannot be ruled out in view of the ubiquity of some compounds. (authors)

  16. Assessment of externalities related to global and local air pollutants with the NEEDS-TIMES Italy model

    Energy Technology Data Exchange (ETDEWEB)

    Pietrapertosa, F.; Cosmi, C.; Loperte, S.; Salvia, M.; Cuomo, V. [National Research Council, Institute of Methodologies for Environmental Analysis, C.da S. Loja, I-85050 Tito Scalo (PZ) (Italy); Di Leo, S. [University of Basilicata, Dept. of Environmental Engineering and Physics, C.da Macchia Romana, I-85100 Potenza (Italy); Macchiato, M. [Federico II University, Dept. of Physical Sciences, Via Cintia, I-80126 Naples (Italy)

    2010-01-15

    This work is aimed to illustrate the potentiality of the multi-region NEEDS-TIMES modelling platform, in the economic evaluation of the environmental damages due to air pollution. In particular the effects of external costs on the least-cost optimised energy system configuration were analysed in a national case study with the NEEDS-TIMES Italy model, considering the externalities related to local and global air pollutants (NO{sub x}, SO{sub 2}, VOC, particulates and GHGs). Different scenarios were compared to emphasise the role of external costs in the achievement of strategic environmental targets. The main results obtained are discussed, focusing on the changes in energy fuel mix as well as in local air pollutants and GHG emissions, highlighting the main conclusions in terms of policy strategies. (author)

  17. Transfer coefficients of energy in mass for X radiation-air: the kV relation and effective energy

    International Nuclear Information System (INIS)

    Teixeira, G.J.; Sousa, C.H.S.; Peixoto, J.G.P.

    2014-01-01

    The objective was to determine, through specific software, the mass-energy transfer coefficients by X-ray beams in air between 30-150 kV. Were generated by the Spectrum Processor program, the spectra and calculated their mass coefficients. The results behaved numerically decreasing order, ranging between 0.3733 and 0.0439 cm 2 /g, inversely proportional to the voltage used and differing behavior of mono-energetic beams above 100 keV. Values align with literal definitions of the interaction of radiation with matter, being useful for dosimetry in diagnostic radiology, including for systems not using an ionization chamber. (author)

  18. Association of long-term exposure to community noise and traffic-related air pollution with coronary heart disease mortality.

    Science.gov (United States)

    Gan, Wen Qi; Davies, Hugh W; Koehoorn, Mieke; Brauer, Michael

    2012-05-01

    In metropolitan areas, road traffic is a major contributor to ambient air pollution and the dominant source of community noise. The authors investigated the independent and joint influences of community noise and traffic-related air pollution on risk of coronary heart disease (CHD) mortality in a population-based cohort study with a 5-year exposure period (January 1994-December 1998) and a 4-year follow-up period (January 1999-December 2002). Individuals who were 45-85 years of age and resided in metropolitan Vancouver, Canada, during the exposure period and did not have known CHD at baseline were included (n = 445,868). Individual exposures to community noise and traffic-related air pollutants, including black carbon, particulate matter less than or equal to 2.5 μm in aerodynamic diameter, nitrogen dioxide, and nitric oxide, were estimated at each person's residence using a noise prediction model and land-use regression models, respectively. CHD deaths were identified from the provincial death registration database. After adjustment for potential confounders, including traffic-related air pollutants or noise, elevations in noise and black carbon equal to the interquartile ranges were associated with 6% (95% confidence interval: 1, 11) and 4% (95% confidence interval: 1, 8) increases, respectively, in CHD mortality. Subjects in the highest noise decile had a 22% (95% confidence interval: 4, 43) increase in CHD mortality compared with persons in the lowest decile. These findings suggest that there are independent effects of traffic-related noise and air pollution on CHD mortality.

  19. Effects of long-term exposure to traffic-related air pollution on respiratory and cardiovascular mortality in the Netherlands: the NLCS-AIR study.

    Science.gov (United States)

    Brunekreef, Bert; Beelen, Rob; Hoek, Gerard; Schouten, Leo; Bausch-Goldbohm, Sandra; Fischer, Paul; Armstrong, Ben; Hughes, Edward; Jerrett, Michael; van den Brandt, Piet

    2009-03-01

    Evidence is increasing that long-term exposure to ambient air pollution is associated with deaths from cardiopulmonary diseases. In a 2002 pilot study, we reported clear indications that traffic-related air pollution, especially at the local scale, was related to cardiopulmonary mortality in a randomly selected subcohort of 5000 older adults participating in the ongoing Netherlands Cohort Study (NLCS) on diet and cancer. In the current study, referred to as NLCS-AIR, our objective was to obtain more precise estimates of the effects of traffic-related air pollution by analyzing associations with cause-specific mortality, as well as lung cancer incidence, in the full cohort of approximately 120,000 subjects. Cohort members were 55 to 69 years of age at enrollment in 1986. Follow-up was from 1987 through 1996 for mortality (17,674 deaths) and from late 1986 through 1997 for lung cancer incidence (2234 cases). Information about potential confounding variables and effect modifiers was available from the questionnaire that subjects completed at enrollment and from publicly available data (including neighborhood-scale information such as income distributions). The NLCS was designed for a case-cohort approach, which makes use of all the cases in the full cohort, while data for the random subcohort are used to estimate person-time experience in the study. Full information on confounders was available for the subjects in the random subcohort and for the emerging cases of mortality and lung cancer incidence during the follow-up period, and in NLCS-AIR we used the case-cohort approach to examine the relation between exposure to air pollution and cause-specific mortality and lung cancer. We also specified a standard Cox proportional hazards model within the full cohort, for which information on potential confounding variables was much more limited. Exposure to air pollution was estimated for the subjects' home addresses at baseline in 1986. Concentrations were estimated for

  20. Prenatal and childhood traffic-related air pollution exposure and childhood executive function and behavior.

    Science.gov (United States)

    Harris, Maria H; Gold, Diane R; Rifas-Shiman, Sheryl L; Melly, Steven J; Zanobetti, Antonella; Coull, Brent A; Schwartz, Joel D; Gryparis, Alexandros; Kloog, Itai; Koutrakis, Petros; Bellinger, David C; Belfort, Mandy B; Webster, Thomas F; White, Roberta F; Sagiv, Sharon K; Oken, Emily

    Traffic-related air pollution exposure may influence brain development and function and thus be related to neurobehavioral problems in children, but little is known about windows of susceptibility. Examine associations of gestational and childhood exposure to traffic-related pollution with executive function and behavior problems in children. We studied associations of pre- and postnatal pollution exposures with neurobehavioral outcomes in 1212 children in the Project Viva pre-birth cohort followed to mid-childhood (median age 7.7years). Parents and classroom teachers completed the Behavior Rating Inventory of Executive Function (BRIEF) and the Strengths and Difficulties Questionnaire (SDQ). Using validated spatiotemporal models, we estimated exposure to black carbon (BC) and fine particulate matter (PM 2.5 ) in the third trimester of pregnancy, from birth to 3years, from birth to 6years, and in the year before behavioral ratings. We also measured residential distance to major roadways and near-residence traffic density at birth and in mid-childhood. We estimated associations of BC, PM 2.5 , and other traffic exposure measures with BRIEF and SDQ scores, adjusted for potential confounders. Higher childhood BC exposure was associated with higher teacher-rated BRIEF Behavioral Regulation Index (BRI) scores, indicating greater problems: 1.0 points (95% confidence interval (CI): 0.0, 2.1) per interquartile range (IQR) increase in birth-age 6BC, and 1.7 points (95% CI: 0.6, 2.8) for BC in the year prior to behavioral ratings. Mid-childhood residential traffic density was also associated with BRI score (0.6, 95% CI: 0.1, 1.1). Birth-age 3BC was not associated with BRIEF or SDQ scores. Third trimester BC exposure was not associated with teacher-rated BRI scores (-0.2, 95% CI: -1.1, 0.8), and predicted lower scores (fewer problems) on the BRIEF Metacognition Index (-1.2, 95% CI: -2.2, -0.2) and SDQ total difficulties (-0.9, 95% CI: -1.4, -0.4). PM 2.5 exposure was

  1. Relation between lead in air and in petrol in two urban areas of Britain

    Science.gov (United States)

    Pattenden, N. J.; Branson, J. R.

    The recent reduction in the lead content of petrol in the United Kingdom, following government legislation, has been used to investigate the relationship between lead in petrol and in outside air in urban environments. In parts of London and Manchester, the airborne lead concentration closely followed the petrol lead concentration, within a time resolution of about 1 month. These results indicate that, in these areas, the petrol lead content has a fairly direct and prompt effect on the urban air lead concentration, i.e. any environmental lead reservoirs in the pathway from petrol to air (and hence to man by inhalation) are not significant on this timescale. A small component of the airborne lead, apparently independent of the petrol lead, was also observed.

  2. Combined effects of road traffic noise and ambient air pollution in relation to risk for stroke?

    Science.gov (United States)

    Sørensen, Mette; Lühdorf, Pernille; Ketzel, Matthias; Andersen, Zorana J; Tjønneland, Anne; Overvad, Kim; Raaschou-Nielsen, Ole

    2014-08-01

    Exposure to road traffic noise and air pollution have both been associated with risk for stroke. The few studies including both exposures show inconsistent results. We aimed to investigate potential mutual confounding and combined effects between road traffic noise and air pollution in association with risk for stroke. In a population-based cohort of 57,053 people aged 50-64 years at enrollment, we identified 1999 incident stroke cases in national registries, followed by validation through medical records. Mean follow-up time was 11.2 years. Present and historical residential addresses from 1987 to 2009 were identified in national registers and road traffic noise and air pollution were modeled for all addresses. Analyses were done using Cox regression. A higher mean annual exposure at time of diagnosis of 10 µg/m(3) nitrogen dioxide (NO2) and 10 dB road traffic noise at the residential address was associated with ischemic stroke with incidence rate ratios (IRR) of 1.11 (95% CI: 1.03, 1.20) and 1.16 (95% CI: 1.07, 1.24), respectively, in single exposure models. In two-exposure models road traffic noise (IRR: 1.15) and not NO2 (IRR: 1.02) was associated with ischemic stroke. The strongest association was found for combination of high noise and high NO2 (IRR=1.28; 95% CI=1.09-1.52). Fatal stroke was positively associated with air pollution and not with traffic noise. In conclusion, in mutually adjusted models road traffic noise and not air pollution was associated ischemic stroke, while only air pollution affected risk for fatal strokes. There were indications of combined effects. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Electronic structure and related properties of ferrocyanide ion calculated by the SCF Xα-scattered wave method

    International Nuclear Information System (INIS)

    Guenzburger, D.; Maffeo, B.; Siqueira, M.L. de

    1975-08-01

    The SCF-XαSW method is used to calculate the electronic structure of the ferrocyanide ion. Optical transitions and X-Ray photoelectron emission are obtained from the energy level scheme and compared with experimental results. The charge density in the Fe nucleus is also computed and the result is correlated with isomer shift measurements made on this and other Fe complexes for which theoretical calculations have been performed

  4. A review of reaction rates and thermodynamic and transport properties for the 11-species air model for chemical and thermal nonequilibrium calculations to 30000 K

    Science.gov (United States)

    Gupta, Roop N.; Yos, Jerrold M.; Thompson, Richard A.

    1989-01-01

    Reaction rate coefficients and thermodynamic and transport properties are provided for the 11-species air model which can be used for analyzing flows in chemical and thermal nonequilibrium. Such flows will likely occur around currently planned and future hypersonic vehicles. Guidelines for determining the state of the surrounding environment are provided. Approximate and more exact formulas are provided for computing the properties of partially ionized air mixtures in such environments.

  5. Physical activity profile of 2014 FIFA World Cup players, with regard to different ranges of air temperature and relative humidity

    Science.gov (United States)

    Chmura, Paweł; Konefał, Marek; Andrzejewski, Marcin; Kosowski, Jakub; Rokita, Andrzej; Chmura, Jan

    2017-04-01

    The present study attempts to assess changes in soccer players' physical activity profiles under the simultaneous influence of the different combinations of ambient temperature and relative humidity characterising matches of the 2014 FIFA World Cup hosted by Brazil. The study material consisted of observations of 340 players representing 32 national teams taking part in the tournament. The measured indices included total distances covered; distances covered with low, moderate, or high intensity; numbers of sprints performed, and peak running speeds achieved. The analysis was carried out using FIFA official match data from the Castrol Performance Index system. Ultimately, consideration was given to a combination of three air temperature ranges, i.e. below 22 °C, 22-28 °C, and above 28 °C; and two relative humidity ranges below 60 % and above 60 %. The greatest average distance recorded (10.54 ± 0.91 km) covered by players at an air temperature below 22 °C and a relative humidity below 60 %, while the shortest (9.83 ± 1.08 km) characterised the same air temperature range, but conditions of relative humidity above 60 % ( p ≤ 0.001). Two-way ANOVA revealed significant differences ( p ≤ 0.001) in numbers of sprints performed by players, depending on whether the air temperature range was below 22 °C (40.48 ± 11.17) or above 28 °C (30.72 ± 9.40), but only where the relative humidity was at the same time below 60 %. Results presented indicate that the conditions most comfortable for physical activity on the part of players occur at 22 °C, and with relative humidity under 60 %.

  6. Individual traffic-related air pollution and new onset adult asthma: A GIS-based pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Sherson, D.; Lysbeck Hansen, C. (Hospital of Vejle, Dept. of Occupational and Environmental Medicine, (Denmark)); Solvang Jensen, S.; Hertel, O. (Univ. of Aarhus, National Environmental Research Institute (Denmark)); Baelum, J. (Odense Univ. Hospital, Dep. of Occupational and Environmental Medicine (Denmark)); Skadhauge, L. (Haderslev Hospital, Dep. of Occupational and Environmental Medicine (Denmark)); Siersted, H.C. (Odense Univ. Hospital, Dep. of Respiratory Medicine (Denmark)); Omland, OE. (Aalborg Hospital, Dep. of Occupational Medicine (Denmark)); Thomsen, G. (South-West Jutland Hospital Esbjerg, Dep. of Occupational and Environmental Medicine (Denmark)); Sigsgaard, T. (Univ. of Aarhus, Institute of Occupational and Environmental Medicine (Denmark))

    2008-03-15

    The objective of this pilot study is to investigate the relation between asthma and wheeze debut and individually estimated exposure to traffic-related air pollutants with a validated exposure system (AirGIS). A non-smoking cohort with recently acquired asthma or wheeze as well as matched controls was identified from a large cross-sectional study. All residential and working addresses with corresponding time periods for a 10 year period were successfully identified for all study participants (N=33) and exposure estimated for both urban background and street level. Individual levels of air pollutants in the years preceding debut of asthma or wheeze were analyzed using survival analysis. No significant correlations between exposure levels and onset of disease or symptom were demonstrated. A tendency towards higher levels of nitrogen oxides exposure during the year prior to debut was seen in wheeze cases. Substantial problems in determining time of onset were encountered. It is recommended that the analytic methods developed in this pilot study are used in a larger prospective cohort to investigate individual trafficrelated air pollutants as a risk factor for the development of new asthma and wheeze. (au)

  7. Predicting Indian Summer Monsoon onset through variations of surface air temperature and relative humidity

    Science.gov (United States)

    Stolbova, Veronika; Surovyatkina, Elena; Kurths, Jurgen

    2015-04-01

    Indian Summer Monsoon (ISM) rainfall has an enormous effect on Indian agriculture, economy, and, as a consequence, life and prosperity of more than one billion people. Variability of the monsoonal rainfall and its onset have a huge influence on food production, agricultural planning and GDP of the country, which on 22% is determined by agriculture. Consequently, successful forecasting of the ISM onset is a big challenge and large efforts are being put into it. Here, we propose a novel approach for predictability of the ISM onset, based on critical transition theory. The ISM onset is defined as an abrupt transition from sporadious rainfall to spatially organized and temporally sustained rainfall. Taking this into account, we consider the ISM onset as is a critical transition from pre-monsoon to monsoon, which take place in time and also in space. It allows us to suggest that before the onset of ISM on the Indian subcontinent should be areas of critical behavior where indicators of the critical transitions can be detected through an analysis of observational data. First, we identify areas with such critical behavior. Second, we use detected areas as reference points for observation locations for the ISM onset prediction. Third, we derive a precursor for the ISM onset based on the analysis of surface air temperature and relative humidity variations in these reference points. Finally, we demonstrate the performance of this precursor on two observational data sets. The proposed approach allows to determine ISM onset in advance in 67% of all considered years. Our proposed approach is less effective during the anomalous years, which are associated with weak/strong monsoons, e.g. El-Nino, La-Nina or positive Indian Ocean Dipole events. The ISM onset is predicted for 23 out of 27 normal monsoon years (85%) during the past 6 decades. In the anomalous years, we show that time series analysis in both areas during the pre-monsoon period reveals indicators whether the

  8. Physical aerosol properties and their relation to air mass origin at Monte Cimone (Italy during the first MINATROC campaign

    Directory of Open Access Journals (Sweden)

    R. Van Dingenen

    2005-01-01

    Full Text Available Aerosol physical properties were measured at the Monte Cimone Observatory (Italy from 1 June till 6 July 2000. The measurement site is located in the transition zone between the continental boundary layer and the free troposphere (FT, at the border between the Mediterranean area and Central Europe, and is exposed to a variety of air masses. Sub-μm number size distributions, aerosol hygroscopicity near 90% RH, refractory size distribution at 270°C and equivalent black carbon mass were continuously measured. Number size distributions and hygroscopic properties indicate that the site is exposed to aged continental air masses, however during daytime it is also affected by upslope winds. The mixing of this transported polluted boundary layer air masses with relatively clean FT air leads to frequent nucleation events around local noon. Night-time size distributions, including fine and coarse fractions for each air mass episode, have been parameterized by a 3-modal lognormal distribution. Number and volume concentrations in the sub-μm modes are strongly affected by the air mass origin, with highest levels in NW-European air masses, versus very clean, free tropospheric air coming from the N-European sector. During a brief but distinct dust episode, the coarse mode is clearly enhanced. The observed hygroscopic behavior of the aerosol is consistent with the chemical composition described by Putaud et al. (2004, but no closure between known chemical composition and measured hygroscopicity could be made because the hygroscopic properties of the water-soluble organic matter (WSOM are not known. The data suggest that WSOM is slightly-to-moderately hygroscopic (hygroscopic growth factor GF at 90% relative humidity between 1.05 and 1.51, and that this property may well depend on the air mass origin and history. External mixing of aerosol particles is observed in all air masses through the occurrence of two hygroscopicity modes (average GF of 1.22 and 1

  9. The relative impacts of distributed and centralized generation of electricity on local air quality in the South Coast Air Basin of California

    International Nuclear Information System (INIS)

    Jing Qiguo; Venkatram, Akula

    2011-01-01

    This paper examines the air quality impact of using distributed generation (DG) to satisfy future growth in power demand in the South Coast Air Basin of Los Angeles, relative to the impact when the demand is met by expanding current central generation (CG) capacity. The impact of decreasing boiler emissions by capturing the waste heat from DGs is not examined. The air quality impacts of these two alternate scenarios are quantified in terms of hourly maximum ground-level and annually averaged primary NO x concentrations, which are estimated using AERMOD. This study focuses on the impact of primary emissions at source-receptor distances of tens of kilometers. We find that the shift to DGs has the potential for decreasing maximum hourly impacts of power generation in the vicinity of the DGs. The maximum hourly concentration is reduced from 25 to 6 ppb if DGs rather than CGs are used to generate power. However, the annually averaged concentrations are likely to be higher than for the scenario in which existing CGs are used to satisfy power demand growth. Future DG penetration will add an annual average of 0.1 ppb to the current basin average, 20 ppb, while expanding existing CGs will add 0.05 ppb. - Highlights: → NO x levels in the LA basin will change by shifting to distributed generation (DG). → Shifting to DG will reduce the maximum hourly concentration from 25 to 6 ppb. → DG will add 0.1 ppb versus 0.05 ppb for CG to the annual average of 20 ppb.

  10. Evaluating heat-related mortality in Korea by objective classifications of 'air masses'

    Czech Academy of Sciences Publication Activity Database

    Kyselý, Jan; Huth, Radan; Kim, J.

    2010-01-01

    Roč. 30, č. 10 (2010), s. 1484-1501 ISSN 0899-8418 R&D Projects: GA ČR GC205/07/J044 Institutional research plan: CEZ:AV0Z30420517 Keywords : weather type classifications * air masses * biometeorology * human mortality * South Korea Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 2.479, year: 2010

  11. A Numerical Simulation of Traffic-Related Air Pollution Exposures in Urban Street Canyons

    Science.gov (United States)

    Liu, J.; Fu, X.; Tao, S.

    2016-12-01

    Urban street canyons are usually associated with intensive vehicle emissions. However, the high buildings successively along both sides of a street block the dispersion of traffic-generated air pollutants, which enhances human exposure and adversely affects human health. In this study, an urban scale traffic pollution dispersion model is developed with the consideration of street distribution, canyon geometry, background meteorology, traffic assignment, traffic emissions and air pollutant dispersion. Vehicle exhausts generated from traffic flows will first disperse inside a street canyon along the micro-scale wind field (generated by computational fluid dynamics (CFD) model) and then leave the street canyon and further disperse over the urban area. On the basis of this model, the effects of canyon geometry on the distribution of NOx and CO from traffic emissions were studied over the center of Beijing, China. We found that an increase of building height along the streets leads to higher pollution levels inside streets and lower pollution levels outside, resulting in higher domain-averaged concentrations over the area. In addition, street canyons with equal (or highly uneven) building heights on two sides of a street tend to lower the urban-scale air pollution concentrations at pedestrian level. Our results indicate that canyon geometry strongly influences human exposure to traffic pollutants in the populated urban area. Carefully planning street layout and canyon geometry in consideration of traffic demand as well as local weather pattern may significantly reduce the chances of unhealthy air being inhaled by urban residents.

  12. STRATEGIES TO REDUCE EXPOSURE TO TRAFFIC-RELATED AIR POLLUTION AT THE LOCAL LEVEL

    Science.gov (United States)

    As public health concerns for populations living, working and going to school near high-traffic roadways have increased, so have the need to identify and implement air pollution control strategies effective at the local level. While strategies implemented at the federal and stat...

  13. Temporal distribution of air quality related to meteorology and road traffic in Madrid.

    Science.gov (United States)

    Perez-Martinez, Pedro J; Miranda, Regina M

    2015-04-01

    The impact of climatology--air temperature, precipitation and wind speed--and road traffic--volume, vehicle speed and percentage of heavy-duty vehicles (HDVs)--on air quality in Madrid was studied by estimating the effect for each explanatory variable using generalized linear regression models controlling for monthly variations, days of week and parameter levels. Every 1 m/s increase in wind speed produced a decrease in PM10 concentrations by 10.3% (95% CI 12.6-8.6) for all weekdays and by 12.4% (95% CI 14.9-9.8) for working days (up to the cut-off of 2.4 m/s). Increases of PM10 concentrations due to air temperature (7.2% (95% CI 6.2-8.3)) and traffic volume (3.3% (95% CI 2.9-3.8)) were observed at every 10 °C and 1 million vehicle-km increases for all weekdays; oppositely, slight decreases of PM10 concentrations due to percentage of HDVs (3.2% (95% CI 2.7-3.7)) and vehicle speed (0.7% (95% CI 0.6-0.8)) were observed at every 1% and 1 km/h increases. Stronger effects of climatology on air quality than traffic parameters were found.

  14. Respiratory disease in relation to outdoor air pollution in Kanpur, India.

    Science.gov (United States)

    Liu, Hai-Ying; Bartonova, Alena; Schindler, Martin; Sharma, Mukesh; Behera, Sailesh N; Katiyar, Kamlesh; Dikshit, Onkar

    2013-01-01

    This paper examines the effect of outdoor air pollution on respiratory disease in Kanpur, India, based on data from 2006. Exposure to air pollution is represented by annual emissions of sulfur dioxide (SO(2)), particulate matter (PM), and nitrogen oxides (NO(x)) from 11 source categories, established as a geographic information system (GIS)-based emission inventory in 2 km × 2 km grid. Respiratory disease is represented by number of patients who visited specialist pulmonary hospital with symptoms of respiratory disease. The results showed that (1) the main sources of air pollution are industries, domestic fuel burning, and vehicles; (2) the emissions of PM per grid are strongly correlated to the emissions of SO(2) and NO(x); and (3) there is a strong correlation between visits to a hospital due to respiratory disease and emission strength in the area of residence. These results clearly indicate that appropriate health and environmental monitoring, actions to reduce emissions to air, and further studies that would allow assessing the development in health status are necessary.

  15. Relation between 222Rn concentration in outdoor air and lower atmosphere

    International Nuclear Information System (INIS)

    Kataoka, Toshio; Mori, Tadashige; Yunoki, Eiji; Michihiro, Kenshuh; Sugiyama, Hirokazu; Shimizu, Mitsuo; Tsukamoto, Osamu; Sahashi, Ken.

    1991-01-01

    Using the height of the surface-based inversion layer obtained by the acoustic sounder returns and the variation of the 222 Rn concentration in the outdoor air during the presence of the surface-based inversion layer, the exhalation rate of 222 Rn is estimated to be 0.020 Bq·m -2 ·s -1 , which is observed elsewhere on land. Furthermore, the exposure rate at 1 m above the air-ground interface due to the short-lived 222 Rn daughters in the outdoor air during the presence of the surface-based inversion layer can be estimated using the height of the surface-based inversion layer and the 222 Rn concentrations in the outdoor air at the ground level before and after the onset of the surface-based inversion layer. From these treatment, it is clearly demonstrated that the monostatic acoustic sounder is useful as a supplementary method for a weather survey which forms a part of monitoring around the nuclear facilities. (author)

  16. Determination of the reference air kerma rate for 192Ir brachytherapy sources and the related uncertainty

    International Nuclear Information System (INIS)

    Dijk, Eduard van; Kolkman-Deurloo, Inger-Karine K.; Damen, Patricia M. G.

    2004-01-01

    Different methods exist to determine the air kerma calibration factor of an ionization chamber for the spectrum of a 192 Ir high-dose-rate (HDR) or pulsed-dose-rate (PDR) source. An analysis of two methods to obtain such a calibration factor was performed: (i) the method recommended by [Goetsch et al., Med. Phys. 18, 462-467 (1991)] and (ii) the method employed by the Dutch national standards institute NMi [Petersen et al., Report S-EI-94.01 (NMi, Delft, The Netherlands, 1994)]. This analysis showed a systematic difference on the order of 1% in the determination of the strength of 192 Ir HDR and PDR sources depending on the method used for determining the air kerma calibration factor. The definitive significance of the difference between these methods can only be addressed after performing an accurate analysis of the associated uncertainties. For an NE 2561 (or equivalent) ionization chamber and an in-air jig, a typical uncertainty budget of 0.94% was found with the NMi method. The largest contribution in the type-B uncertainty is the uncertainty in the air kerma calibration factor for isotope i, N k i , as determined by the primary or secondary standards laboratories. This uncertainty is dominated by the uncertainties in the physical constants for the average mass-energy absorption coefficient ratio and the stopping power ratios. This means that it is not foreseeable that the standards laboratories can decrease the uncertainty in the air kerma calibration factors for ionization chambers in the short term. When the results of the determination of the 192 Ir reference air kerma rates in, e.g., different institutes are compared, the uncertainties in the physical constants are the same. To compare the applied techniques, the ratio of the results can be judged by leaving out the uncertainties due to these physical constants. In that case an uncertainty budget of 0.40% (coverage factor=2) should be taken into account. Due to the differences in approach between the

  17. Association between traffic-related air pollution in schools and cognitive development in primary school children: a prospective cohort study.

    Directory of Open Access Journals (Sweden)

    Jordi Sunyer

    2015-03-01

    Full Text Available Air pollution is a suspected developmental neurotoxicant. Many schools are located in close proximity to busy roads, and traffic air pollution peaks when children are at school. We aimed to assess whether exposure of children in primary school to traffic-related air pollutants is associated with impaired cognitive development.We conducted a prospective study of children (n = 2,715, aged 7 to 10 y from 39 schools in Barcelona (Catalonia, Spain exposed to high and low traffic-related air pollution, paired by school socioeconomic index; children were tested four times (i.e., to assess the 12-mo developmental trajectories via computerized tests (n = 10,112. Chronic traffic air pollution (elemental carbon [EC], nitrogen dioxide [NO2], and ultrafine particle number [UFP; 10-700 nm] was measured twice during 1-wk campaigns both in the courtyard (outdoor and inside the classroom (indoor simultaneously in each school pair. Cognitive development was assessed with the n-back and the attentional network tests, in particular, working memory (two-back detectability, superior working memory (three-back detectability, and inattentiveness (hit reaction time standard error. Linear mixed effects models were adjusted for age, sex, maternal education, socioeconomic status, and air pollution exposure at home. Children from highly polluted schools had a smaller growth in cognitive development than children from the paired lowly polluted schools, both in crude and adjusted models (e.g., 7.4% [95% CI 5.6%-8.8%] versus 11.5% [95% CI 8.9%-12.5%] improvement in working memory, p = 0.0024. Cogently, children attending schools with higher levels of EC, NO2, and UFP both indoors and outdoors experienced substantially smaller growth in all the cognitive measurements; for example, a change from the first to the fourth quartile in indoor EC reduced the gain in working memory by 13.0% (95% CI 4.2%-23.1%. Residual confounding for social class could not be discarded completely

  18. Association between traffic-related air pollution in schools and cognitive development in primary school children: a prospective cohort study.

    Science.gov (United States)

    Sunyer, Jordi; Esnaola, Mikel; Alvarez-Pedrerol, Mar; Forns, Joan; Rivas, Ioar; López-Vicente, Mònica; Suades-González, Elisabet; Foraster, Maria; Garcia-Esteban, Raquel; Basagaña, Xavier; Viana, Mar; Cirach, Marta; Moreno, Teresa; Alastuey, Andrés; Sebastian-Galles, Núria; Nieuwenhuijsen, Mark; Querol, Xavier

    2015-03-01

    Air pollution is a suspected developmental neurotoxicant. Many schools are located in close proximity to busy roads, and traffic air pollution peaks when children are at school. We aimed to assess whether exposure of children in primary school to traffic-related air pollutants is associated with impaired cognitive development. We conducted a prospective study of children (n = 2,715, aged 7 to 10 y) from 39 schools in Barcelona (Catalonia, Spain) exposed to high and low traffic-related air pollution, paired by school socioeconomic index; children were tested four times (i.e., to assess the 12-mo developmental trajectories) via computerized tests (n = 10,112). Chronic traffic air pollution (elemental carbon [EC], nitrogen dioxide [NO2], and ultrafine particle number [UFP; 10-700 nm]) was measured twice during 1-wk campaigns both in the courtyard (outdoor) and inside the classroom (indoor) simultaneously in each school pair. Cognitive development was assessed with the n-back and the attentional network tests, in particular, working memory (two-back detectability), superior working memory (three-back detectability), and inattentiveness (hit reaction time standard error). Linear mixed effects models were adjusted for age, sex, maternal education, socioeconomic status, and air pollution exposure at home. Children from highly polluted schools had a smaller growth in cognitive development than children from the paired lowly polluted schools, both in crude and adjusted models (e.g., 7.4% [95% CI 5.6%-8.8%] versus 11.5% [95% CI 8.9%-12.5%] improvement in working memory, p = 0.0024). Cogently, children attending schools with higher levels of EC, NO2, and UFP both indoors and outdoors experienced substantially smaller growth in all the cognitive measurements; for example, a change from the first to the fourth quartile in indoor EC reduced the gain in working memory by 13.0% (95% CI 4.2%-23.1%). Residual confounding for social class could not be discarded completely; however

  19. Statistics of surface divergence and their relation to air-water gas transfer velocity

    Science.gov (United States)

    Asher, William E.; Liang, Hanzhuang; Zappa, Christopher J.; Loewen, Mark R.; Mukto, Moniz A.; Litchendorf, Trina M.; Jessup, Andrew T.

    2012-05-01

    Air-sea gas fluxes are generally defined in terms of the air/water concentration difference of the gas and the gas transfer velocity,kL. Because it is difficult to measure kLin the ocean, it is often parameterized using more easily measured physical properties. Surface divergence theory suggests that infrared (IR) images of the water surface, which contain information concerning the movement of water very near the air-water interface, might be used to estimatekL. Therefore, a series of experiments testing whether IR imagery could provide a convenient means for estimating the surface divergence applicable to air-sea exchange were conducted in a synthetic jet array tank embedded in a wind tunnel. Gas transfer velocities were measured as a function of wind stress and mechanically generated turbulence; laser-induced fluorescence was used to measure the concentration of carbon dioxide in the top 300 μm of the water surface; IR imagery was used to measure the spatial and temporal distribution of the aqueous skin temperature; and particle image velocimetry was used to measure turbulence at a depth of 1 cm below the air-water interface. It is shown that an estimate of the surface divergence for both wind-shear driven turbulence and mechanically generated turbulence can be derived from the surface skin temperature. The estimates derived from the IR images are compared to velocity field divergences measured by the PIV and to independent estimates of the divergence made using the laser-induced fluorescence data. Divergence is shown to scale withkLvalues measured using gaseous tracers as predicted by conceptual models for both wind-driven and mechanically generated turbulence.

  20. Is there any interaction between domestic radon exposure and air pollution from traffic in relation to childhood leukemia risk?

    DEFF Research Database (Denmark)

    Bräuner, E.V.; Andersen, Claus Erik; Andersen, H.P.

    2010-01-01

    risk within different strata of air pollution and traffic density. Results: The relative risk for childhood leukemia in association with a 103 Bq/m3-years increase in radon was 1.77 (1.11, 2.82) among those exposed to high levels of NOx and 1.23 (0.79, 1.91) for those exposed to low levels of NOx...

  1. Subsolidus Phase Relations of the SrO-In2O3-CuO System in Air

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude; Thydén, Karl Tor Sune

    2013-01-01

    The subsolidus phase relations of the SrO-In2O3-CuO system were investigated at 900 °C in air. Under these conditions, five binary oxide phases are stable: Sr2CuO3, SrCuO2, Sr14Cu24O41, In2Cu2O5 and SrIn2O4. The pseudo-ternary section is characterised by six three-phase regions and is dominated...

  2. Are we Breathing Clean Air in Metro Manila? (Nuclear and Related Analytical Techniques and Receptor Modeling Revealing the Real Score)

    International Nuclear Information System (INIS)

    Pabroa, Preciosa Corazon B.

    2015-01-01

    Air Particulate matter (APM) is a mixture of different pollutant sources which can be of anthropogenic and/or natural origin, of which the size of great concern with regard to adverse effects on human health are generally less than 10μm (Referred to as PM10). Identification and apportionment of pollutant sources is important to be able to have better understanding of prevailing conditions in the area and thus better air quality management can be applied. APM (PM10) at sampling sites in Metro Manila (Philippines) has been monitored since 1998 for the primary purpose of source identification and source apportionment. APM samples (fractionated into coarse (PM2.5-10) and fine (PM2.5) fractions) were collected using a Gent air sampler. Particulate mass was determined by gravimetry and black carbon by reflectometry organic carbon/elemental carbon by thermal optical reflectance. Elemental concentrations were determined using nuclear and related analytical techniques such as the particle-induced x-ray emission (PIXE) spectrometry and x-ray fluorescence (XRF) spectrometry. Source apportionment of fine air particles was done using PMF2. Result show PM10 levels to be in compliance to the Philippine 1-year guideline value of 60 μg m“-“3 but in exceedance of the US EPA 1-year standard of 15 μg m“-“3 and the WHO 1-year guideline value of 10 μg m“-“3. Annual mean % Fine BC levels range from 33% to 59%, but individual points can reach up to more than 80% of the PM2.5 levels. Pb level in the fine fraction exhibit decreasing trend coinciding with the introduction of unleaded-gasoline starting in 1998 and the eventual phase-out of the use of leaded-gasoline in 2001. Six air pollution sources have been identified in the fine fraction with vehicular emissions making up the bulk at about 50%. Other sources are smoke, secondary S, fine soil and industry. Addressing problems regarding traffic-related activities can greatly reduce the fine particulate pollution problems

  3. Analysis of various tracts of mastoid air cells related to CSF leak after the anterior transpetrosal approach.

    Science.gov (United States)

    Tamura, Ryota; Tomio, Ryosuke; Mohammad, Farrag; Toda, Masahiro; Yoshida, Kazunari

    2018-03-16

    OBJECTIVE The anterior transpetrosal approach (ATPA) was established in 1984 and has been particularly effective for petroclival tumors. Although some complications associated with this approach, such as venous hemorrhage in the temporal lobe and nervous disturbances, have been resolved over the years, the incidence rate of CSF leaks has not greatly improved. In this study, some varieties of air cell tracts that are strongly related to CSF leaks are demonstrated. In addition, other pre- and postoperative risk factors for CSF leakage after ATPA are discussed. METHODS Preoperative and postoperative target imaging of the temporal bone was performed in a total of 117 patients who underwent ATPA, and various surgery-related parameters were analyzed. RESULTS The existence of air cells at the petrous apex, as well as fluid collection in the mastoid antrum detected by a postoperative CT scan, were possible risk factors for CSF leakage. Tracts that directly connected to the antrum from the squamous part of the temporal bone and petrous apex, rather than through numerous air cells, were significantly related to CSF leak and were defined as "direct tract." All patients with a refractory CSF leak possessed "unusual tracts" that connected to the attic, tympanic cavity, or eustachian tube, rather than through the mastoid antrum. CONCLUSIONS Preoperative assessment of petrous pneumatization types is necessary to prevent CSF leaks. Direct and unusual tracts are particularly strong risk factors for CSF leaks.

  4. Noninvasive method using multidetector CT for calculating the relative blood supply ratio of duplicated renal arteries in renal donors

    International Nuclear Information System (INIS)

    Kuwabara, Masatomo; Kim, Tonsok; Nakamura, Hironobu; Narumi, Yoshifumi; Takahashi, Satoru; Sato, Yoshinobu; Murakami, Takamichi

    2006-01-01

    The aim of this study was to evaluate the correlation between the renal artery cross-sectional area measured by multidetector computed tomography (MDCT) and the nephrogram area calculated by renal arteriography in potential living renal donors with duplicated renal arteries. Medical records of 18 patients with duplicated renal arteries who underwent both MDCT angiography and renal arteriography between 2001 and 2003 were retrospectively reviewed. All 20 kidneys were evaluated. Renal artery cross-sectional areas were measured using the workstation to which the CT data were transferred; the nephrogram areas on the digitized angiographic images were calculated using public domain software. Bland-Altman analysis was performed to compare the cross-sectional area ratio of the accessory arteries to the main renal arteries, with the ratios obtained from the nephrogram areas calculated from the arteriograms. The mean cross-sectional areas of the accessory and main renal arteries were 6.78 and 20.9 mm 2 , respectively. The ratio of the nephrogram areas calculated from the arteriograms ranged from 0.094 to 0.809. Bland-Altman analysis showed no significant difference. It is possible to predict the supply volume of accessory renal arteries by measuring the cross-sectional area of the accessory and main renal arteries in potential living renal donors. (author)

  5. Toward calculations of the 129Xe chemical shift in Xe@C60 at experimental conditions: Relativity, correlation, and dynamics

    Czech Academy of Sciences Publication Activity Database

    Straka, Michal; Lantto, P.; Vaara, J.

    2008-01-01

    Roč. 112, č. 12 (2008), s. 2658-2668 ISSN 1089-5639 Institutional research plan: CEZ:AV0Z40550506 Keywords : NMR * theoretical calculations * role of dynamics Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.871, year: 2008

  6. Air conditioning technology. Vol. 1. Calculation, design, meteorological data. Standards, guidelines. As of October 31, 1986. Raumlufttechnik. Bd. 1. Berechnung, Konstruktion, meteorologische Daten. Normen, Richtlinien. Stand der abgedruckten Normen: 31. Oktober 1986

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    Since 1970 the energy consumption of air-conditioning systems has almost been reduced by half. This has been achieved by means of improved technologies and on the basis of a change in technological awareness. Revised DIN Standards have contributed to this as well. The application of the standards compiled in the DIN pocket book No. 217 'Raumlufttechnik 1' (Air-conditioning Technology 1) will secure the associated systems to actually generate the desired air-conditioning effects. With its major DIN Standards for the calculation and design of air-conditioning systems, this DIN pocket book turns out to be a valuable guide and tool for planners, manufacturers and operators. In addition, its annex supplies substantiated information on the control of HVAC systems (VDI/VDE 3525 BI) and contains the guideline for the acceptance testing of HVAC systems (VDI/2079), the draft for the building inspection guideline on fire protection requirements on ventilation systems, and annotations for air-conditioning installations in public buildings.

  7. Ambient concentrations of aldehydes in relation to Beijing Olympic air pollution control measures

    Science.gov (United States)

    Gong, J. C.; Zhu, T.; Hu, M.; Zhang, L. W.; Cheng, H.; Zhang, L.; Tong, J.; Zhang, J.

    2010-08-01

    Aldehydes are ubiquitous constituents of the atmosphere. Their concentrations are elevated in polluted urban atmospheres. The present study was carried out to characterize three aldehydes of most health concern (formaldehyde, acetaldehyde, and acrolein) in a central Beijing site in the summer and early fall of 2008 (from June to October). Measurements were made before, during, and after the Beijing Olympics to examine whether the air pollution control measures implemented to improve Beijing's air quality during the Olympics had any impact on concentrations of the three aldehydes. Average concentrations of formaldehyde, acetaldehyde and acrolein were 29.34 ± 15.12 μg/m3, 27.09 ± 15.74 μg/m3 and 2.32 ± 0.95 μg/m3, respectively, for the entire period of measurements, all being the highest among the levels measured in cities around the world in photochemical smog seasons. Among the three measured aldehydes, only acetaldehyde had a substantially reduced mean concentration during the Olympic air pollution control period compared to the pre-Olympic period. Formaldehyde and acrolein followed the changing pattern of temperature and were each significantly correlated with ozone (a secondary product of photochemical reactions). In contrast, acetaldehyde was significantly correlated with several pollutants emitted mainly from local emission sources (e.g., NO2, CO, and PM2.5). These findings suggest that local direct emissions had a larger impact on acetaldehyde than formaldehyde and acrolein.

  8. Relative power density distribution calculations of the Kori unit 1 pressurized water reactor with full-scope explicit modeling of monte carlo simulation

    International Nuclear Information System (INIS)

    Kim, J. O.; Kim, J. K.

    1997-01-01

    Relative power density distributions of the Kori unit 1 pressurized water reactor calculated by Monte Carlo modeling with the MCNP code. The Kori unit 1 core is modeled on a three-dimensional representation of the one-eighth of the reactor in-vessel component with reflective boundaries at 0 and 45 degrees. The axial core model is based on half core symmetry and is divided into four axial segments. Fission reaction density in each rod is calculated by following 100 cycles with 5,000 test neutrons in each cycle after starting with a localized neutron source and ten noncontributing settle cycles. Relative assembly power distributions are calculated from fission reaction densities of rods in assembly. After 100 cycle calculations, the system coverages to a κ value of 1.00039 ≥ 0.00084. Relative assembly power distribution is nearly the same with that of the Kori unit 1 FSAR. Applicability of the full-scope Monte Carlo simulation in the power distribution calculation is examined by the relative root mean square error of 2.159%. (author)

  9. Mobile phone tracking: in support of modelling traffic-related air pollution contribution to individual exposure and its implications for public health impact assessment

    Science.gov (United States)

    2013-01-01

    We propose a new approach to assess the impact of traffic-related air pollution on public health by mapping personal trajectories using mobile phone tracking technology in an urban environment. Although this approach is not based on any empirical studies, we believe that this method has great potential and deserves serious attention. Mobile phone tracking technology makes it feasible to generate millions of personal trajectories and thereby cover a large fraction of an urban population. Through analysis, personal trajectories are not only associated to persons, but it can also be associated with vehicles, vehicle type, vehicle speed, vehicle emission rates, and sources of vehicle emissions. Pollution levels can be estimated by dispersion models from calculated traffic emissions. Traffic pollution exposure to individuals can be estimated based on the exposure along the individual human trajectories in the estimated pollution concentration fields by utilizing modelling tools. By data integration, one may identify trajectory patterns of particularly exposed human groups. The approach of personal trajectories may open a new paradigm in understanding urban dynamics and new perspectives in population-wide empirical public health research. This new approach can be further applied to individual commuter route planning, land use planning, urban traffic network planning, and used by authorities to formulate air pollution mitigation policies and regulations. PMID:24188173

  10. Use of nuclear and related analytical techniques in environmental research as exemplified by selected air pollution studies

    International Nuclear Information System (INIS)

    Smodis, B.; Jacimovic, R.; Jeran, Z.; Stropnik, B.; Svetina, M.

    2000-01-01

    Among nuclear and nuclear related analytical techniques, neutron activation analysis and X-ray fluorescence spectrometry proved to be particularly useful for environmental studies owing to their nondestructive character and multi element capability. This paper emphasizes their importance among other multielement analytical methods by discussing their specific role due to specific physics basis, quite different to other destructive non-nuclear methods, and by summarizing results obtained in several studies related to air pollution research, including analyses of airborne particulate matter, water samples, lichens and mosses. (author)

  11. Relation between calculated Lennard-Jones potential and thermal stability of Cu-based bulk metallic glasses

    International Nuclear Information System (INIS)

    Lin, T.; Bian, X.F.; Jiang, J.

    2006-01-01

    Two metallic bulk glasses, Cu 60 Zr 30 Ti 10 and Cu 47 Ti 33 Zr 11 Ni 8 Si 1 , with a diameter of 3 mm were prepared by copper mold casting method. Dilatometric measurement was carried out on the two glassy alloys to obtain information about the average nearest-neighbour distance r 0 and the effective depth of pair potential V 0 . By assuming a Lennard-Jones potential, r 0 and V 0 were calculated to be 0.28 nm and 0.16 eV for Cu 60 Zr 30 Ti 10 and 0.27 nm and 0.13 eV for Cu 47 Ti 33 Zr 11 Ni 8 Si 1 , respectively. It was found that the glassy alloy Cu 60 Zr 30 Ti 10 was more stable than Cu 47 Ti 33 Zr 11 Ni 8 Si 1 against heating from both experiment and calculation

  12. Some applications of the particle-in-a-box eigenfunctions: fast-convergent variational and related calculations

    International Nuclear Information System (INIS)

    Pathak, R.K.; Chandra, A.K.; Bhattacharyya, K.

    1994-01-01

    Eigenfunctions of the quantum mechanical particle-in-a-box problem are shown to lead to a new trigonometric expansion scheme with good convergence properties. This hitherto unexplored expansion strategy is found to be quite efficient in variational calculations and as an alternative to the Fourier series. Demonstrative computations involve a few one-dimensional models of confining potentials for bound states and pulses of various shapes in signal analysis. ((orig.))

  13. Applicability of the Environmental Relative Moldiness Index for Quantification of Residential Mold Contamination in an Air Pollution Health Effects Study

    Directory of Open Access Journals (Sweden)

    Ali Kamal

    2014-01-01

    Full Text Available The Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS investigated the impact of exposure to traffic-related air pollution on the respiratory health of asthmatic children in Detroit, Michigan. Since indoor mold exposure may also contribute to asthma, floor dust samples were collected in participants homes (n=112 to assess mold contamination using the Environmental Relative Moldiness Index (ERMI. The repeatability of the ERMI over time, as well as ERMI differences between rooms and dust collection methods, was evaluated for insights into the application of the ERMI metric. ERMI values for the standard settled floor dust samples had a mean ± standard deviation of 14.5±7.9, indicating high levels of mold contamination. ERMI values for samples collected from the same home 1 to 7 months apart (n=52 were consistent and without systematic bias. ERMI values for separate bedroom and living room samples were highly correlated (r=0.69, n=66. Vacuum bag dust ERMI values were lower than for floor dust but correlated (r=0.58, n=28. These results support the use of the ERMI to evaluate residential mold exposure as a confounder in air pollution health effects studies.

  14. Traffic-Related Air Pollution and Risk of Preterm Birth in the San Joaquin Valley of California

    Science.gov (United States)

    Padula, Amy M.; Mortimer, Kathleen M.; Tager, Ira B.; Hammond, S. Katharine; Lurmann, Frederick W.; Yang, Wei; Stevenson, David K.; Shaw, Gary M.

    2014-01-01

    We evaluated associations between traffic-related air pollution during pregnancy and preterm birth in births in four counties in California during years 2000–2006. We used logistic regression to examine the association between the highest quartile of ambient air pollutants (carbon monoxide, nitrogen dioxide, particulate matter <10 and 2.5 μm) and traffic density during pregnancy and each of five levels of prematurity based on gestational age at birth (20–23, 24–27, 28–31, 32–33 and 34–36 weeks) versus term (37–42 weeks). We examined trimester averages and the last month and last 6 weeks of pregnancy. Models were adjusted for birth weight, maternal age, race/ethnicity, education, prenatal care and birth costs payment. Neighborhood socioeconomic status was evaluated as a potential effect modifier. There were increased odds ratios for early preterm birth for those exposed to the highest quartile of each pollutant during the second trimester and the end of pregnancy (adjusted odds ratios: 1.4– 2.8). Associations were stronger among mothers living in low socioeconomic status neighborhoods (adjusted odds ratios: 2.1–4.3). We observed exposure-response associations for multiple pollutant exposures and early preterm birth. Inverse associations during the first trimester were observed. The results confirm associations between traffic-related air pollution and prematurity, particularly among very early preterm births and low socioeconomic status neighborhoods. PMID:25453347

  15. Traffic-related air pollution and risk of preterm birth in the San Joaquin Valley of California.

    Science.gov (United States)

    Padula, Amy M; Mortimer, Kathleen M; Tager, Ira B; Hammond, S Katharine; Lurmann, Frederick W; Yang, Wei; Stevenson, David K; Shaw, Gary M

    2014-12-01

    To evaluate associations between traffic-related air pollution during pregnancy and preterm birth in births in four counties in California during years 2000 to 2006. We used logistic regression to examine the association between the highest quartile of ambient air pollutants (carbon monoxide, nitrogen dioxide, particulate matter prematurity based on gestational age at birth (20-23, 24-27, 28-31, 32-33, and 34-36 weeks) versus term (37-42 weeks). We examined trimester averages and the last month and the last 6 weeks of pregnancy. Models were adjusted for birthweight, maternal age, race/ethnicity, education, prenatal care, and birth costs payment. Neighborhood socioeconomic status (SES) was evaluated as a potential effect modifier. There were increased odds ratios (ORs) for early preterm birth for those exposed to the highest quartile of each pollutant during the second trimester and the end of pregnancy (adjusted OR, 1.4-2.8). Associations were stronger among mothers living in low SES neighborhoods (adjusted OR, 2.1-4.3). We observed exposure-response associations for multiple pollutant exposures and early preterm birth. Inverse associations during the first trimester were observed. The results confirm associations between traffic-related air pollution and prematurity, particularly among very early preterm births and low SES neighborhoods.

  16. Using continuous sampling to examine the distribution of traffic related air pollution in proximity to a major road

    Science.gov (United States)

    McAdam, Kim; Steer, Peter; Perrotta, Kim

    2011-04-01

    A study to characterize the distribution of vehicle related air pollution in proximity to a major arterial road was undertaken to inform local land use planning and policy regarding separation distances that could help reduce exposure for new sensitive land use development. Measurements of criteria air contaminants were made at ground level, 10 m, 30 m, and 60 m from curb side, and at 9 m height, 10 m from curb side along a traffic corridor carrying over 34,000 vehicles per day. Pollutant decay with distance or height was not statistically significant for O 3, CO, or SO 2. No clear distance decay pattern emerged for PM 2.5. Compared to concentrations at ground level 30 m from curb side, concentrations at 10 m, 60 m, and 10 m at 9 m height were 83%, 45% and 54% higher, respectively. For NO, NO 2, and NO x, however, there was a statistically significant decline in concentrations with distance with the decay most apparent from 30 m to 60 m from the road. Concentrations at 10 m from curb side at 9 m height were equivalent to (all wind conditions) or less than (downwind conditions) those at 30 m and ground level. These findings suggest that for protection of public health in the near road environment, vertical distance is an important determinant of exposure to pollutants that are key indicators of traffic related air pollution. This has implications for sensitive land use development in proximity to high volume traffic corridors.

  17. Transport and its energy-related air pollution problems in Bangkok

    Energy Technology Data Exchange (ETDEWEB)

    Boontherawara, N.; Panich, S.; Phiu-Nual, K.

    1995-12-31

    Suspended Particulate Matter (SPM) is a major pollutant, followed by carbon monoxide and lead, as the ambient levels of these pollutants all exceed international standards such as those laid down by the World Health Organization (WHO). In order to meet these standards, it is necessary to reduce the emissions of these pollutants by 84.9%, 47.3%, and 13.0% respectively. Ambient air quality in Bangkok will continue to deteriorate to an unacceptable level by the year 2000, if no action is taken over and above implementation of already approved projects (including mass transit projects). Carbon monoxide and hydrocarbon emissions could be reduced by 28 and 22% respectively, with the implementation of Reasonable Technology Measures used to control vehicle emissions alone. These measures include inspection and maintenance programs. Their success is dependent on effective quality control and on the application of stringent standards. However, these measures would have little impact in reducing the emissions of SPM. It can therefore be concluded that Reasonable Technology Measures will be insufficient to address Bangkok`s air pollution problems, without complementary measures to reduce traffic congestion. Implementation of the traffic measures outlined under the Demand-Management Policy Scenario alone will reduce CO and HC emissions by up to 45%. These measures serve to reduce traffic congestion and increase the average travel speed. However, in order to improve air quality to internationally acceptable levels, traffic measures must be implemented in conjunction with the Reasonable Technology Scenario. This will provide an additional reduction of CO and HC emissions by 45%.

  18. A regression-based method for mapping traffic-related air pollution. Application and testing in four contrasting urban environments

    International Nuclear Information System (INIS)

    Briggs, D.J.; De Hoogh, C.; Elliot, P.; Gulliver, J.; Wills, J.; Kingham, S.; Smallbone, K.

    2000-01-01

    Accurate, high-resolution maps of traffic-related air pollution are needed both as a basis for assessing exposures as part of epidemiological studies, and to inform urban air-quality policy and traffic management. This paper assesses the use of a GIS-based, regression mapping technique to model spatial patterns of traffic-related air pollution. The model - developed using data from 80 passive sampler sites in Huddersfield, as part of the SAVIAH (Small Area Variations in Air Quality and Health) project - uses data on traffic flows and land cover in the 300-m buffer zone around each site, and altitude of the site, as predictors of NO 2 concentrations. It was tested here by application in four urban areas in the UK: Huddersfield (for the year following that used for initial model development), Sheffield, Northampton, and part of London. In each case, a GIS was built in ArcInfo, integrating relevant data on road traffic, urban land use and topography. Monitoring of NO 2 was undertaken using replicate passive samplers (in London, data were obtained from surveys carried out as part of the London network). In Huddersfield, Sheffield and Northampton, the model was first calibrated by comparing modelled results with monitored NO 2 concentrations at 10 randomly selected sites; the calibrated model was then validated against data from a further 10-28 sites. In London, where data for only 11 sites were available, validation was not undertaken. Results showed that the model performed well in all cases. After local calibration, the model gave estimates of mean annual NO 2 concentrations within a factor of 1.5 of the actual mean (approx. 70-90%) of the time and within a factor of 2 between 70 and 100% of the time. r 2 values between modelled and observed concentrations are in the range of 0.58-0.76. These results are comparable to those achieved by more sophisticated dispersion models. The model also has several advantages over dispersion modelling. It is able, for example, to

  19. Long-term traffic air and noise pollution in relation to mortality and hospital readmission among myocardial infarction survivors.

    Science.gov (United States)

    Tonne, Cathryn; Halonen, Jaana I; Beevers, Sean D; Dajnak, David; Gulliver, John; Kelly, Frank J; Wilkinson, Paul; Anderson, H Ross

    2016-01-01

    There is relatively little evidence of health effects of long-term exposure to traffic-related pollution in susceptible populations. We investigated whether long-term exposure to traffic air and noise pollution was associated with all-cause mortality or hospital readmission for myocardial infarction (MI) among survivors of hospital admission for MI. Patients from the Myocardial Ischaemia National Audit Project database resident in Greater London (n = 1 8,138) were followed for death or readmission for MI. High spatially-resolved annual average air pollution (11 metrics of primary traffic, regional or urban background) derived from a dispersion model (resolution 20 m × 20 m) and road traffic noise for the years 2003-2010 were used to assign exposure at residence. Hazard ratios (HR, 95% confidence interval (CI)) were estimated using Cox proportional hazards models. Most air pollutants were positively associated with all-cause mortality alone and in combination with hospital readmission. The largest associations with mortality per interquartile range (IQR) increase of pollutant were observed for non-exhaust particulate matter (PM(10)) (HR = 1.05 (95% CI 1.00, 1.10), IQR = 1.1 μg/m(3)); oxidant gases (HR = 1.05 (95% CI 1.00, 1.09), IQR = 3.2 μg/m(3)); and the coarse fraction of PM (HR = 1.05 (95% CI 1.00, 1.10), IQR = 0.9 μg/m(3)). Adjustment for traffic noise only slightly attenuated these associations. The association for a 5 dB increase in road-traffic noise with mortality was HR = 1.02 (95% CI 0.99, 1.06) independent of air pollution. These data support a relationship of primary traffic and regional/urban background air pollution with poor prognosis among MI survivors. Although imprecise, traffic noise appeared to have a modest association with prognosis independent of air pollution. Copyright © 2015 The Authors. Published by Elsevier GmbH.. All rights reserved.

  20. Air rifles are more than toys: BB gun-related traumatic brain injury.

    Science.gov (United States)

    Klopotek, Blaine; Weibley, Richard; Chapados, Rene

    2014-12-01

    Gunshot wounds are traumatic events that emergency departments around the country treat on a daily basis. An increasing number of these wounds are being caused by air rifles that shoot ball bearings (ie, BB guns) and, although uncommon, the results can be fatal. The general public and most practitioners may not realize the damage these "toys" can inflict. This article highlights an unfortunate event involving a BB gun accidentally discharged at close range and the consequences. Data from recent and older studies are discussed regarding the firepower of these guns and their potential for injury. Copyright 2014, SLACK Incorporated.

  1. Matrix of Title V-Related And Air Grant-Eligible Activities

    Science.gov (United States)

    This document may be of assistance in applying the Title V air operating permit regulations. This document is part of the Title V Policy and Guidance Database available at www2.epa.gov/title-v-operating-permits/title-v-operating-permit-policy-and-guidance-document-index. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  2. Concentrations of Staphylococcus species in indoor air as associated with other bacteria, season, relative humidity, air change rate, and S. aureus-positive occupants.

    Science.gov (United States)

    Madsen, Anne Mette; Moslehi-Jenabian, Saloomeh; Islam, Md Zohorul; Frankel, Mika; Spilak, Michal; Frederiksen, Margit W

    2018-01-01

    The aim of this study was to obtain knowledge about concentrations of Staphylococcus aureus, MRSA (methicillin-resistant S. aureus), and other Staphylococcus species in indoor air in Greater Copenhagen and about factors affecting the concentrations. The effects of season, temperature, relative humidity, air change rate (ACR), other bacterial genera, area per occupant, and presence of S. aureus-positive occupants were studied. In samples from 67 living rooms, S. hominis, S. warneri, S. epidermidis, and S. capitis were found in 13-25%; S. saprophyticus, S. cohnii, and S. pasteuri in 5-10%; and S. lugdunensis, S. haemolyticus, S. caprae, S. equorum, S. kloosii, S. pettenkoferi, S. simulans, and S. xylosus in less than 3%. Staphylococcus aureus were found in two of 67 living rooms: spa type t034 (an MRSA) was recovered from a farmhouse, while spa type t509 was found in an urban home. Two species, S. equorum and S. kloosii, were found only in the farmhouse. Staphylococcus was significantly associated with season with lowest concentration and richness in winter. Genera composition was associated with ACR with smaller fractions of Staphylococcus at higher ACR, while richness was significantly and negatively associated with area per occupant. Concentration of Staphylococcus correlated positively with the total concentration of bacteria, but negatively with the total concentration of other bacteria. The concentration of Staphylococcus was not significantly associated with concentrations of the other abundant genera Bacillus, Kocuria, and Micrococcus. In offices with S. aureus-positive occupants, airborne S. aureus was not found. In conclusion, Staphylococcus species constitute a considerable proportion of the airborne bacteria in the studied homes and offices. However, both S. aureus and MRSA had very low prevalence during all seasons. Thus, transmission of S. aureus and MRSA through the air in living rooms in Copenhagen is expected to be limited. The negative associations

  3. Uncertainty evaluation of the kerma in the air, related to the active volume in the ionization chamber of concentric cylinders, by Monte Carlo simulation; Avaliacao de incerteza no kerma no ar, em relacao ao volume ativo da camara de ionizacao de cilindros concentricos, por simulacao de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Lo Bianco, A.S.; Oliveira, H.P.S.; Peixoto, J.G.P., E-mail: abianco@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. Nacional de Metrologia das Radiacoes Ionizantes (LNMRI)

    2009-07-01

    To implant the primary standard of the magnitude kerma in the air for X-ray between 10 - 50 keV, the National Metrology Laboratory of Ionizing Radiations (LNMRI) must evaluate all the uncertainties of measurement related with Victtoren chamber. So, it was evaluated the uncertainty of the kerma in the air consequent of the inaccuracy in the active volume of the chamber using the calculation of Monte Carlo as a tool through the Penelope software

  4. Traffic-related air pollution and health co-benefits of alternative transport in Adelaide, South Australia.

    Science.gov (United States)

    Xia, Ting; Nitschke, Monika; Zhang, Ying; Shah, Pushan; Crabb, Shona; Hansen, Alana

    2015-01-01

    Motor vehicle emissions contribute nearly a quarter of the world's energy-related greenhouse gases and cause non-negligible air pollution, primarily in urban areas. Changing people's travel behaviour towards alternative transport is an efficient approach to mitigate harmful environmental impacts caused by a large number of vehicles. Such a strategy also provides an opportunity to gain health co-benefits of improved air quality and enhanced physical activities. This study aimed at quantifying co-benefit effects of alternative transport use in Adelaide, South Australia. We made projections for a business-as-usual scenario for 2030 with alternative transport scenarios. Separate models including air pollution models and comparative risk assessment health models were developed to link alternative transport scenarios with possible environmental and health benefits. In the study region with an estimated population of 1.4 million in 2030, by shifting 40% of vehicle kilometres travelled (VKT) by passenger vehicles to alternative transport, annual average urban PM2.5 would decline by approximately 0.4μg/m(3) compared to business-as-usual, resulting in net health benefits of an estimated 13deaths/year prevented and 118 disability-adjusted life years (DALYs) prevented per year due to improved air quality. Further health benefits would be obtained from improved physical fitness through active transport (508deaths/year prevented, 6569DALYs/year prevented), and changes in traffic injuries (21 deaths and, 960 DALYs prevented). Although uncertainties remain, our findings suggest that significant environmental and health benefits are possible if alternative transport replaces even a relatively small portion of car trips. The results may provide assistance to various government organisations and relevant service providers and promote collaboration in policy-making, city planning and infrastructure establishment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Impact of commuting exposure to traffic-related air pollution on cognitive development in children walking to school.

    Science.gov (United States)

    Alvarez-Pedrerol, Mar; Rivas, Ioar; López-Vicente, Mònica; Suades-González, Elisabet; Donaire-Gonzalez, David; Cirach, Marta; de Castro, Montserrat; Esnaola, Mikel; Basagaña, Xavier; Dadvand, Payam; Nieuwenhuijsen, Mark; Sunyer, Jordi

    2017-12-01

    A few studies have found associations between the exposure to traffic-related air pollution at school and/or home and cognitive development. The impact on cognitive development of the exposure to air pollutants during commuting has not been explored. We aimed to assess the role of the exposure to traffic-related air pollutants during walking commute to school on cognitive development of children. We performed a longitudinal study of children (n = 1,234, aged 7-10 y) from 39 schools in Barcelona (Catalonia, Spain) who commuted by foot to school. Children were tested four times during a 12-month follow-up to characterize their developmental trajectories of working memory (d' of the three-back numbers test) and inattentiveness (hit reaction time standard error of the Attention Network Test). Average particulate matter ≤2.5 μm (PM 2.5 ), Black Carbon (BC) and NO 2 concentrations were estimated using Land Use Regression for the shortest walking route to school. Differences in cognitive growth were evaluated by linear mixed effects models with age-by-pollutant interaction terms. Exposure to PM 2.5 and BC from the commutes by foot was associated with a reduction in the growth of working memory (an interquartile range increase in PM 2.5 and BC concentrations decreased the annual growth of working memory by 5.4 (95% CI [-10.2, -0.6]) and 4.6 (95% CI [-9.0, -0.1]) points, respectively). The findings for NO 2 were not conclusive and none of the pollutants were associated with inattentiveness. Efforts should be made to implement pedestrian school pathways through low traffic streets in order to increase security and minimize children's exposure to air pollutants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. A novel mobile monitoring approach to characterize spatial and temporal variation in traffic-related air pollutants in an urban community

    Science.gov (United States)

    Yu, Chang Ho; Fan, Zhihua; Lioy, Paul J.; Baptista, Ana; Greenberg, Molly; Laumbach, Robert J.

    2016-09-01

    Air concentrations of traffic-related air pollutants (TRAPs) vary in space and time within urban communities, presenting challenges for estimating human exposure and potential health effects. Conventional stationary monitoring stations/networks cannot effectively capture spatial characteristics. Alternatively, mobile monitoring approaches became popular to measure TRAPs along roadways or roadsides. However, these linear mobile monitoring approaches cannot thoroughly distinguish spatial variability from temporal variations in monitored TRAP concentrations. In this study, we used a novel mobile monitoring approach to simultaneously characterize spatial/temporal variations in roadside concentrations of TRAPs in urban settings. We evaluated the effectiveness of this mobile monitoring approach by performing concurrent measurements along two parallel paths perpendicular to a major roadway and/or along heavily trafficked roads at very narrow scale (one block away each other) within short time period (monitors, including battery-operated PM2.5 monitor (SidePak), condensation particle counter (CPC 3007), black carbon (BC) monitor (Micro-Aethalometer), carbon monoxide (CO) monitor (Langan T15), and portable temperature/humidity data logger (HOBO U12), and a GPS-based tracker (Trackstick). Sampling was conducted for ∼3 h in the morning (7:30-10:30) in 7 separate days in March/April and 6 days in May/June 2012. Two simultaneous samplings were made at 5 spatially-distributed locations on parallel roads, usually distant one block each other, in each neighborhood. The 5-min averaged BC concentrations (AVG ± SD, [range]) were 2.53 ± 2.47 [0.09-16.3] μg/m3, particle number concentrations (PNC) were 33,330 ± 23,451 [2512-159,130] particles/cm3, PM2.5 mass concentrations were 8.87 ± 7.65 [0.27-46.5] μg/m3, and CO concentrations were 1.22 ± 0.60 [0.22-6.29] ppm in the community. The traffic-related air pollutants, BC and PNC, but not PM2.5 or CO, varied spatially depending on

  7. A review of reaction rates and thermodynamic and transport properties for an 11-species air model for chemical and thermal nonequilibrium calculations to 30000 K

    Science.gov (United States)

    Gupta, Roop N.; Yos, Jerrold M.; Thompson, Richard A.; Lee, Kam-Pui

    1990-01-01

    Reaction rate coefficients and thermodynamic and transport properties are reviewed and supplemented for the 11-species air model which can be used for analyzing flows in chemical and thermal nonequilibrium up to temperatures of 3000 K. Such flows will likely occur around currently planned and future hypersonic vehicles. Guidelines for determining the state of the surrounding environment are provided. Curve fits are given for the various species properties for their efficient computation in flowfield codes. Approximate and more exact formulas are provided for computing the properties of partially ionized air mixtures in a high energy environment. Limitations of the approximate mixing laws are discussed for a mixture of ionized species. An electron number-density correction for the transport properties of the charged species is obtained. This correction has been generally ignored in the literature.

  8. Reprocessing and reuse of waste tire rubber to solve air-quality related problems

    Science.gov (United States)

    Lehmann, C.M.B.; Rostam-Abadi, M.; Rood, M.J.; Sun, Jielun

    1998-01-01

    There is a potential for using waste tire rubber to make activated-carbon adsorbents for air-quality control applications. Such an approach provides a recycling path for waste tires and the production of new adsorbents from a low-cost waste material. Tire-derived activated carbons (TDACs) were prepared from waste tires. The resulting products are generally mesoporous, with N2-BET specific surface areas ranging from 239 to 1031 m2/g. TDACs were tested for their ability to store natural gas and remove organic compounds and mercury species from gas streams. TDACs are able to achieve 36% of the recommended adsorbed natural gas (methane) storage capacity for natural-gas-fueled vehicles. Equilibrium adsorption capacities for CH4 achieved by TDACs are comparable to Calgon BPL, a commercially available activated-carbon adsorbent. The acetone adsorption capacity for a TDAC is 67% of the adsorption capacity achieved by BPL at 1 vol % acetone. Adsorption capacities of mercury in simulated flue-gas streams are, in general, larger than adsorption capacities achieved by coal-derived activated carbons (CDACs) and BPL. Although TDACs may not perform as well as commercial adsorbents in some air pollution control applications, the potential lower cost of TDACS should be considered when evaluating economics.

  9. The application of the German reg. guides ('elements of calculation') for radioactive discharges via exhaust air and waste water on fuel element fabrication

    International Nuclear Information System (INIS)

    Hille, R.; Rudolph, W.

    1978-01-01

    The fuel element fabricating plants at Hanau are handlung uranium, plutonium and thorium. The process essentially of converting these heavy metals into oxide, carbide or metal compounds. Thereby occur radioactive discharges into the exhaust air and the waste water. The most important pathway for exposure from these substances is inhalation, the released radionuclides mostly being α-emitters. Compared to this the external irradiation from immersion in γ, β, and neutron radiation is of less importance. (orig./HP) [de

  10. Assessment and economic valuation of air pollution impacts on human health over Europe and the United States as calculated by a multi-model ensemble in the framework of AQMEII3

    Science.gov (United States)

    Im, Ulas; Brandt, Jørgen; Geels, Camilla; Mantzius Hansen, Kaj; Heile Christensen, Jesper; Skou Andersen, Mikael; Solazzo, Efisio; Kioutsioukis, Ioannis; Alyuz, Ummugulsum; Balzarini, Alessandra; Baro, Rocio; Bellasio, Roberto; Bianconi, Roberto; Bieser, Johannes; Colette, Augustin; Curci, Gabriele; Farrow, Aidan; Flemming, Johannes; Fraser, Andrea; Jimenez-Guerrero, Pedro; Kitwiroon, Nutthida; Liang, Ciao-Kai; Nopmongcol, Uarporn; Pirovano, Guido; Pozzoli, Luca; Prank, Marje; Rose, Rebecca; Sokhi, Ranjeet; Tuccella, Paolo; Unal, Alper; Garcia Vivanco, Marta; West, Jason; Yarwood, Greg; Hogrefe, Christian; Galmarini, Stefano

    2018-04-01

    The impact of air pollution on human health and the associated external costs in Europe and the United States (US) for the year 2010 are modeled by a multi-model ensemble of regional models in the frame of the third phase of the Air Quality Modelling Evaluation International Initiative (AQMEII3). The modeled surface concentrations of O3, CO, SO2 and PM2.5 are used as input to the Economic Valuation of Air Pollution (EVA) system to calculate the resulting health impacts and the associated external costs from each individual model. Along with a base case simulation, additional runs were performed introducing 20 % anthropogenic emission reductions both globally and regionally in Europe, North America and east Asia, as defined by the second phase of the Task Force on Hemispheric Transport of Air Pollution (TF-HTAP2). Health impacts estimated by using concentration inputs from different chemistry-transport models (CTMs) to the EVA system can vary up to a factor of 3 in Europe (12 models) and the United States (3 models). In Europe, the multi-model mean total number of premature deaths (acute and chronic) is calculated to be 414 000, while in the US, it is estimated to be 160 000, in agreement with previous global and regional studies. The economic valuation of these health impacts is calculated to be EUR 300 billion and 145 billion in Europe and the US, respectively. A subset of models that produce the smallest error compared to the surface observations at each time step against an all-model mean ensemble results in increase of health impacts by up to 30 % in Europe, while in the US, the optimal ensemble mean led to a decrease in the calculated health impacts by ˜ 11 %. A total of 54 000 and 27 500 premature deaths can be avoided by a 20 % reduction of global anthropogenic emissions in Europe and the US, respectively. A 20 % reduction of North American anthropogenic emissions avoids a total of ˜ 1000 premature deaths in Europe and 25 000 total premature deaths in the

  11. Assessment and economic valuation of air pollution impacts on human health over Europe and the United States as calculated by a multi-model ensemble in the framework of AQMEII3

    Directory of Open Access Journals (Sweden)

    U. Im

    2018-04-01

    Full Text Available The impact of air pollution on human health and the associated external costs in Europe and the United States (US for the year 2010 are modeled by a multi-model ensemble of regional models in the frame of the third phase of the Air Quality Modelling Evaluation International Initiative (AQMEII3. The modeled surface concentrations of O3, CO, SO2 and PM2.5 are used as input to the Economic Valuation of Air Pollution (EVA system to calculate the resulting health impacts and the associated external costs from each individual model. Along with a base case simulation, additional runs were performed introducing 20 % anthropogenic emission reductions both globally and regionally in Europe, North America and east Asia, as defined by the second phase of the Task Force on Hemispheric Transport of Air Pollution (TF-HTAP2. Health impacts estimated by using concentration inputs from different chemistry–transport models (CTMs to the EVA system can vary up to a factor of 3 in Europe (12 models and the United States (3 models. In Europe, the multi-model mean total number of premature deaths (acute and chronic is calculated to be 414 000, while in the US, it is estimated to be 160 000, in agreement with previous global and regional studies. The economic valuation of these health impacts is calculated to be EUR 300 billion and 145 billion in Europe and the US, respectively. A subset of models that produce the smallest error compared to the surface observations at each time step against an all-model mean ensemble results in increase of health impacts by up to 30 % in Europe, while in the US, the optimal ensemble mean led to a decrease in the calculated health impacts by  ∼  11 %. A total of 54 000 and 27 500 premature deaths can be avoided by a 20 % reduction of global anthropogenic emissions in Europe and the US, respectively. A 20 % reduction of North American anthropogenic emissions avoids a total of  ∼  1000 premature

  12. Indoor environmental and air quality characteristics, building-related health symptoms, and worker productivity in a federal government building complex.

    Science.gov (United States)

    Lukcso, David; Guidotti, Tee Lamont; Franklin, Donald E; Burt, Allan

    2016-01-01

    Building Health Sciences, Inc. (BHS), investigated environmental conditions by many modalities in 71 discreet areas of 12 buildings in a government building complex that had experienced persistent occupant complaints despite correction of deficiencies following a prior survey. An online health survey was completed by 7,637 building occupants (49% response rate), a subset of whom voluntarily wore personal sampling apparatus and underwent medical evaluation. Building environmental measures were within current standards and guidelines, with few outliers. Four environmental factors were consistently associated with group-level building-related health complaints: physical comfort/discomfort, odor, job stress, and glare. Several other factors were frequently commented on by participants, including cleanliness, renovation and construction activities, and noise. Low relative humidity was significantly associated with lower respiratory and "sick building syndrome"-type symptoms. No other environmental conditions (including formaldehyde, PM10 [particulate matter with an aerodynamic diameter work but at reduced capacity), and increase in reported symptom-days, including symptoms not related to respiratory disease. We found that in buildings without unusual hazards and with environmental and air quality indicators within the range of acceptable indoor air quality standards, there is an identifiable population of occupants with a high prevalence of asthma and allergic disease who disproportionately report discomfort and lost productivity due to symptoms and that in "normal" buildings these outcome indicators are more closely associated with host factors than with environmental conditions. We concluded from the experience of this study that building-related health complaints should be investigated at the work-area level and not at a building-wide level. An occupant-centric medical evaluation should guide environmental investigations, especially when screening results of building

  13. Development of CHARMM-Compatible Force-Field Parameters for Cobalamin and Related Cofactors from Quantum Mechanical Calculations.

    Science.gov (United States)

    Pavlova, Anna; Parks, Jerry M; Gumbart, James C

    2018-02-13

    Corrinoid cofactors such as cobalamin are used by many enzymes and are essential for most living organisms. Therefore, there is broad interest in investigating cobalamin-protein interactions with molecular dynamics simulations. Previously developed parameters for cobalamins are based mainly on crystal structure data. Here, we report CHARMM-compatible force field parameters for several corrinoids developed from quantum mechanical calculations. We provide parameters for corrinoids in three oxidation states, Co 3+ , Co 2+ , and Co 1+ , and with various axial ligands. Lennard-Jones parameters for the cobalt center in the Co(II) and Co(I) states were optimized using a helium atom probe, and partial atomic charges were obtained with a combination of natural population analysis (NPA) and restrained electrostatic potential (RESP) fitting approaches. The Force Field Toolkit was used to optimize all bonded terms. The resulting parameters, determined solely from calculations of cobalamin alone or in water, were then validated by assessing their agreement with density functional theory geometries and by analyzing molecular dynamics simulation trajectories of several corrinoid proteins for which X-ray crystal structures are available. In each case, we obtained excellent agreement with the reference data. In comparison to previous CHARMM-compatible parameters for cobalamin, we observe a better agreement for the fold angle and lower RMSD in the cobalamin binding site. The approach described here is readily adaptable for developing CHARMM-compatible force-field parameters for other corrinoids or large biomolecules.

  14. Recent changes in solar irradiance and infrared irradiance related with air temperature and cloudiness at the King Sejong Station, Antarctica

    Science.gov (United States)

    Jung, Y.; Kim, J.; Cho, H.; Lee, B.

    2006-12-01

    The polar region play a critical role in the surface energy balance and the climate system of the Earth. The important question in the region is that what is the role of the Antarctic atmospheric heat sink of global climate. Thus, this study shows the trends of global solar irradiance, infrared irradiance, air temperature and cloudiness measured at the King Sejong station, Antarctica, during the period of 1996-2004 and determines their relationship and variability of the surface energy balance. Annual average of solar radiation and cloudiness is 81.8 Wm-2 and 6.8 oktas and their trends show the decrease of -0.24 Wm-2yr-1(-0.30 %yr-1) and 0.02 oktas yr-1(0.30 %yr-1). The change of solar irradiance is directly related to change of cloudiness and decrease of solar irradiance presents radiative cooling at the surface. Monthly mean infrared irradiance, air temperature and specific humidity shows the decrease of -2.11 Wm^{- 2}yr-1(-0.75 %yr-1), -0.07 'Cyr-1(-5.15 %yr-1) and -0.044 gkg-1yr-1(-1.42 %yr-1), respectively. Annual average of the infrared irradiance is 279.9 Wm-2 and correlated with the air temperature, specific humidity and cloudiness. A multiple regression model for estimation of the infrared irradiance using the components has been developed. Effects of the components on the infrared irradiance changes show 52 %, 19 % and 10 % for air temperature, specific humidity and cloudiness, respectively. Among the components, air temperature has a great influence on infrared irradiance. Despite the increase of cloudiness, the decrease in the infrared irradiance is due to the decrease of air temperature and specific humidity which have a cooling effect. Therefore, the net radiation of the surface energy balance shows radiative cooling of negative 11-24 Wm^{- 2} during winter and radiative warming of positive 32-83 Wm-2 during the summer. Thus, the amount of shortage and surplus at the surface is mostly balanced by turbulent flux of sensible and latent heat.

  15. Background air pollution studies in urban and rural areas of Bangladesh using nuclear-related analytical techniques

    International Nuclear Information System (INIS)

    Khan, A.H.; Khaliquzzaman, M.; Tarafdar, S.A.; Biswas, S.K.; Islam, A.

    1994-01-01

    The trace element constituents of aerosols such as Hg, Pb, Cd, Se, As, Cu, Zn, Cr, V, etc. are permanent pollutants affecting the biosphere and the general ecosystem. The measurements of these elements collected on air filters, in rainwater, and also in some bioindicators such as moss and lichen, can yield very significant information on the origin, transport, removal and deposition of these pollutants. A set of sensitive and precise nuclear-related and chemical methods such as PIXE, EDXRF, FAAS and DPASV have, therefore, been developed and applied to analyze a number of trace and minor elements in air particulates, coal fly ash, plant materials, moss and water. Further analytical developments would include INAA and TRXRF. Some of the results from air particulates (integral), coal fly ash and moss analyses are presented to illustrate the experience level of the Laboratory. A core programme of study on the trace element composition of aerosols from urban and rural atmosphere in Bangladesh has been planned for implementation within the framework of this CRP. 10 refs, 1 fig., 5 tabs

  16. Use of nuclear and nuclear-related analytical techniques in studies of trace and minor elements in air pollution

    International Nuclear Information System (INIS)

    Smodis, Borut; Stropnik, Boris

    1994-01-01

    Among nuclear and nuclear-related analytical techniques, neutron activation and X-ray fluorescence analysis are particularly useful for environmental studies owing to their non-destructive character and multi-element capability. In this work, procedures for k o -standardized instrumental neutron activation analysis (INAA) and energy-dispersive X-ray fluorescence (EDXRF) spectrometry for trace and minor elements in air pollution studies were investigated. The methods applied were validated by the analysis of suitable reference materials. Using INAA, 20 experimentally obtained elemental values out of 21 certified and all 29 experimentally obtained values compared with 'consensus' values (for the elements where no certified numbers are available) in two SRMs were statistically indistinguishable. Also, the contents of 28 elements in candidate NIST SRM 1573a Tomato Leaves are reported. The EDXRF results were statistically indistinguishable from certified values for eight out of nine elements in NIST SRM 3087. The detection limit for this method is around at 0.1 μg cm -2 per element, so in BCR CRM No. 128, which is intended for ambient air pollution data, only Fe and Zn out of 14 elements reported in the certificate were detected with acceptable precision (i.e., 10%) owing to the very low air particulate matter loading, lying in the region of only 250 μg cm -2 . (Author)

  17. Socioeconomic inequalities and exposure to traffic-related air pollution in the city of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Mateus Habermann

    2014-01-01

    Full Text Available Air pollution is a leading public health concern. In addition, poor populations have been reported as showing increased exposure to such pollution. The current study thus aimed to evaluate the socioeconomic status of the population exposed to vehicle-related air pollution in the city of São Paulo, Brazil. The study used data from the 2010 Census on head-of-household’s mean monthly income and the percentage of households connected to the sewage system. Exposure to air pollutants was estimated according to traffic density in the census tract plus a 200m surrounding buffer. The relationship between exposure and socioeconomic variables was analyzed by the Kruskal-Wallis test. Exposure increased with increasing socioeconomic status (p < 0.001. The population with the highest socioeconomic status lives in the most polluted areas of the city. However, place of residence alone is not capable of measuring exposure. The study suggests that future epidemiological studies include other indicators of vulnerability.

  18. Air-pulse OCE for assessment of age-related changes in mouse cornea in vivo

    International Nuclear Information System (INIS)

    Li, Jiasong; Wang, Shang; Singh, M; Larin, K V; Aglyamov, S; Emelianov, S; Twa, M D

    2014-01-01

    We demonstrate the use of phase-stabilized swept source optical coherence elastography (PhS-SSOCE) to assess the relaxation rate of deformation created by a focused air-pulse in tissue-mimicking gelatin phantoms of various concentrations and mouse corneas of different ages in vivo. The results show that the relaxation rate can be quantified and is different for gels with varying concentrations of gelatin and mouse corneas of different ages. The results indicate that gel phantoms with higher concentrations of gelatin as well as older mouse corneas have faster relaxation rates indicating stiffer material. This non-contact and non-invasive measurement technique utilizes low surface displacement amplitude (in µm scale) for tissue excitation and, therefore, can be potentially used to study the biomechanical properties of ocular and other sensitive tissues. (letter)

  19. Assessment of codes, by-laws and regulations relating to air wells in building design

    Science.gov (United States)

    Fadzil, Sharifah Fairuz Syed; Karamazaman, Nazli

    2017-10-01

    Codes and by-laws concerning air well design (for buildings and lavatories) in Malaysia has been established in the Malaysian Uniform Building By-Laws UBBL number 40 (1) and (2) since the 1980s. Wells are there to fulfill the ventilation and daylighting requirements. The minimum well area according to building storey height are compared between UBBL and the Singapore's well requirements from the Building Construction Authority BCA. A visual and graphical representation (with schematics building and well diagrams drawn to scale) of the minimum well sizes and dimensions is given. It can be seen that if the minimum requirement of well size is used for buildings above 8 storeys high, a thin well resulted which is not proportionate to the building height. A proposed dimension is graphed and given to be used in the UBBL which translated to graphics (3 dimensional buildings drawn to scale) created a much better well proportion.

  20. [An AIDS-related cognitive map in a sample of drug abusers in Buenos Aires City].

    Science.gov (United States)

    Kornblit, A L; Bilyk, A

    1990-01-01

    This paper is an approach to AIDS as a topic among a drug abusers sample of the city of Buenos Aires. Research was carried out on the basis of a qualitative methodology. In an attempt at surveying opinions and attitudes of such a sample as regards AIDS (i.e. subjects' cognitive map), 21 drug abusers from three different rehabilitation programs operating in the B.A. area were interviewed. On the basis of the research performed, the authors elaborate communication strategies among drug abusers that would be helpful for authorities engaged in AIDS prevention to adopt. To boost a strategy likely to break up the AIDS-drug association existing in the mind of many an abuser would be highly advisable so that a separation be settled between both representations, thus giving drug abusers a higher motivation for self-care practice.

  1. Relation between the degree of lung pollution by air pollution and heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, H; Endo, R; Takemoto, K

    1975-04-01

    Human and dog lungs were analyzed for 13 kinds of heavy metals. The human lungs (all of Tokyo citizens) showed a broad range of dust sedimentation, some correlation between the degree of pollution and the amount of cadmium, nickel, and chromium only, and conspicuous individual differences seemingly due to occupation. No correlation was found between the amount of pulmonary metals, and age, or sex. In dog lungs there was no correlation between the local pollution and the amount of iron, copper, zinc, cobalt, and cadmium. Cadmium, nickel, lead, and chromium showed a correlation between local air pollution in human lungs. In dogs obtained in Korea, Ni and Cr were higher than in dog lungs obtained in Jinsen.

  2. SU-C-BRC-05: Monte Carlo Calculations to Establish a Simple Relation of Backscatter Dose Enhancement Around High-Z Dental Alloy to Its Atomic Number

    Energy Technology Data Exchange (ETDEWEB)

    Utsunomiya, S; Kushima, N; Katsura, K; Tanabe, S; Hayakawa, T; Sakai, H; Yamada, T; Takahashi, H; Abe, E; Wada, S; Aoyama, H [Niigata University, Niigata (Japan)

    2016-06-15

    Purpose: To establish a simple relation of backscatter dose enhancement around a high-Z dental alloy in head and neck radiation therapy to its average atomic number based on Monte Carlo calculations. Methods: The PHITS Monte Carlo code was used to calculate dose enhancement, which is quantified by the backscatter dose factor (BSDF). The accuracy of the beam modeling with PHITS was verified by comparing with basic measured data namely PDDs and dose profiles. In the simulation, a high-Z alloy of 1 cm cube was embedded into a tough water phantom irradiated by a 6-MV (nominal) X-ray beam of 10 cm × 10 cm field size of Novalis TX (Brainlab). The ten different materials of high-Z alloys (Al, Ti, Cu, Ag, Au-Pd-Ag, I, Ba, W, Au, Pb) were considered. The accuracy of calculated BSDF was verified by comparing with measured data by Gafchromic EBT3 films placed at from 0 to 10 mm away from a high-Z alloy (Au-Pd-Ag). We derived an approximate equation to determine the relation of BSDF and range of backscatter to average atomic number of high-Z alloy. Results: The calculated BSDF showed excellent agreement with measured one by Gafchromic EBT3 films at from 0 to 10 mm away from the high-Z alloy. We found the simple linear relation of BSDF and range of backscatter to average atomic number of dental alloys. The latter relation was proven by the fact that energy spectrum of backscatter electrons strongly depend on average atomic number. Conclusion: We found a simple relation of backscatter dose enhancement around high-Z alloys to its average atomic number based on Monte Carlo calculations. This work provides a simple and useful method to estimate backscatter dose enhancement from dental alloys and corresponding optimal thickness of dental spacer to prevent mucositis effectively.

  3. Lattice energy calculation - A quick tool for screening of cocrystals and estimation of relative solubility. Case of flavonoids

    Science.gov (United States)

    Kuleshova, L. N.; Hofmann, D. W. M.; Boese, R.

    2013-03-01

    Cocrystals (or multicomponent crystals) have physico-chemical properties that are different from crystals of pure components. This is significant in drug development, since the desired properties, e.g. solubility, stability and bioavailability, can be tailored by binding two substances into a single crystal without chemical modification of an active component. Here, the FLEXCRYST program suite, implemented with a data mining force field, was used to estimate the relative stability and, consequently, the relative solubility of cocrystals of flavonoids vs their pure crystals, stored in the Cambridge Structural Database. The considerable potency of this approach for in silico screening of cocrystals, as well as their relative solubility, was demonstrated.

  4. Acute changes in pulse pressure in relation to constituents of particulate air pollution in elderly persons

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, Lotte [Occupational and Environmental Medicine, Unit of Lung Toxicology, K.U.Leuven, Leuven (Belgium); Buczynska, Anna [Departement of Chemistry, UA, Wilrijk (Belgium); Walgraeve, Christophe [Research group EnVOC, Department of Sustainable Organic Chemistry and Technology, UGent, Gent (Belgium); Delcloo, Andy [Royal Meteorological Institute, Brussels (Belgium); Potgieter-Vermaak, Sanja [Departement of Chemistry, UA, Wilrijk (Belgium); Molecular Science Institute, School of Chemistry, University of Witwatersrand, Johannesburg (South Africa); Division of Chemistry and Environmental Science, Manchester Metropolitan University, Manchester (United Kingdom); Van Grieken, Rene [Departement of Chemistry, UA, Wilrijk (Belgium); Demeestere, Kristof; Dewulf, Jo; Van Langenhove, Herman [Research group EnVOC, Department of Sustainable Organic Chemistry and Technology, UGent, Gent (Belgium); De Backer, Hugo [Royal Meteorological Institute, Brussels (Belgium); Nemery, Benoit, E-mail: ben.nemery@med.kuleuven.be [Occupational and Environmental Medicine, Unit of Lung Toxicology, K.U.Leuven, Leuven (Belgium); Nawrot, Tim S. [Occupational and Environmental Medicine, Unit of Lung Toxicology, K.U.Leuven, Leuven (Belgium); Centre for Environmental Sciences, Hasselt University, Diepenbeek (Belgium)

    2012-08-15

    An increased pulse pressure (difference between systoli