WorldWideScience

Sample records for air currents

  1. Ozone - Current Air Quality Index

    Science.gov (United States)

    ... more announcements Air Quality Basics Air Quality Index | Ozone | Particle Pollution | Smoke from fires | What You Can ... Partners Kids Movies NAQ Conferences NOAA Older Adults Ozone Particle Pollution (PM2.5, PM10) Publications Publicaciones (En ...

  2. The corona discharge current in flowing air

    International Nuclear Information System (INIS)

    The DC corona discharge of both polarities, burning in flowing air (0.08-0.8 ms-1) was investigated. A cylindrical discharge tube consisting of five identical and electrically separated sections was used. A negligible effect of air flow on the positive corona properties and a conspicuous increase of the negative corona current with increasing flow velocity of the air were observed. A novel explanation of these effects is proposed. (author) 2 tabs., 6 figs., 10 refs

  3. Dispersal and air entrainment in unconfined dilute pyroclastic density currents

    Science.gov (United States)

    Andrews, Benjamin J.

    2014-09-01

    Unconfined scaled laboratory experiments show that 3D structures control the behavior of dilute pyroclastic density currents (PDCs) during and after liftoff. Experiments comprise heated and ambient temperature 20 μm talc powder turbulently suspended in air to form density currents within an unobstructed 8.5 × 6 × 2.6-m chamber. Comparisons of Richardson, thermal Richardson, Froude, Stokes, and settling numbers and buoyant thermal to kinetic energy densities show good agreement between experimental currents and dilute PDCs. The experimental Reynolds numbers are lower than those of PDCs, but the experiments are fully turbulent; thus, the large-scale dynamics are similar between the two systems. High-frequency, simultaneous observation in three orthogonal planes shows that the currents behave very differently than previous 2D (i.e., confined) currents. Specifically, whereas ambient temperature currents show radial dispersal patterns, buoyancy reversal, and liftoff of heated currents focuses dispersal along narrow axes beneath the rising plumes. The aspect ratios, defined as the current length divided by a characteristic width, are typically 2.5-3.5 in heated currents and 1.5-2.5 in ambient temperature currents, reflecting differences in dispersal between the two types of currents. Mechanisms of air entrainment differ greatly between the two currents: entrainment occurs primarily behind the heads and through the upper margins of ambient temperature currents, but heated currents entrain air through their lateral margins. That lateral entrainment is much more efficient than the vertical entrainment, >0.5 compared to ˜0.1, where entrainment is defined as the ratio of cross-stream to streamwise velocity. These experiments suggest that generation of coignimbrite plumes should focus PDCs along narrow transport axes, resulting in elongate rather than radial deposits.

  4. Summary Day 1: Second AirMonTech Workshop, Current and Future Air Quality Monitoring

    OpenAIRE

    Querol, Xavier

    2012-01-01

    Presentación resumen de las ponencias del primer día de las Second AirMonTech Workshop, Current and Future Air Quality Monitoring. Estas jornadas tuvieron lugar en Barcelona del 25 al 26 de abril de 2012.

  5. Design of air-core transformer for pulsed current system

    International Nuclear Information System (INIS)

    In this paper, a strip air-core pulse transformer is designed to convert the current. And, how it works and the process of making is elaborated in detail. The transformer contains leads, insulator, copper strip and supporting core. Under the conditions of the charging voltage 2500 V, 5.52 kA and 1.48 kA peak current of primary and secondary windings are obtained, and correspondingly, the current rising rate is 37 A/μs and 138 A/μs. It is supported by analysis and experiment that the transformer can reduce the requirement of the rising rate of the switching current effectively. So, the thyristor can be used in the pulse current system which has a high current rising rate and improve its performance on repetition and stability. (authors)

  6. Recent developments and current status of air kerma standards

    International Nuclear Information System (INIS)

    Primary Standard Dosimetry Laboratories (PSDL) usually maintain air kerma standards for kilovoltage x-rays (10 kV to 300 kV) and for 137Cs- and 60Co-γ radiation. Free-air ionisation chambers (FAC) and cavity ionisation chambers are used as primary air kerma standards for kilovoltage x-rays and for 137Cs- and 60Co-γ radiation, respectively. The majority of the National Metrology Institutes (NMIs) signed the Mutual Recognition Arrangement (MRA) of national measurement standards and of calibration and measurement certificates issued by NMIs. The MRA has been available for signature since 14th October 1999. According to the MRA, the signatories participate in CIPM key comparisons executed by the Consultative Committees or the BIPM, leading to a key comparison reference value. The degree of equivalence of a national measurement standard is expressed quantitatively in terms of its deviation from the key comparison reference value and the uncertainty of this deviation. For air kerma standards the Consultative Committee for Ionising Radiation (CCRI(I)) currently maintains three types of key comparisons and a so-called supplementary comparison. The air kerma key comparisons are organised bilaterally and are carried out between the air kerma standards of the BIPM and the participating NMIs. The radiations used are low-energy (10 kV to 50 kV) and medium energy (100 kV to 250 kV) x-ray beams and 137Cs- and 60Co-γ radiation. To be entitled to enter the key comparison database with respect to air kerma an NMI has to participate in a key comparison within a time period of 10 years. In keeping with the longstanding method of presenting the data, the CCRI(I) took the decision at its meeting in 1999 to use the BIPM determination of air kerma rate as the key comparison reference value. For this reason the BIPM air kerma standards are of special importance. Due to the fact that the air kerma key comparisons have been conducted on an ongoing basis since 1966 for low-energy x

  7. Do current levels of air pollution kill? The impact of air pollution on population mortality in England

    OpenAIRE

    Janke, KM; Propper, C; J. Henderson

    2009-01-01

    The current air quality limit values for airborne pollutants in the UK are low by historical standards and are at levels that are believed not to harm health. We assess whether this view is correct. We examine the relationship between common sources of airborne pollution and population mortality for England. We use data at local authority level for 1998-2005 to examine whether current levels of airborne pollution, as measured by annual mean concentrations of carbon monoxide, nitrogen dioxide,...

  8. Exploring Faraday's Law of Electrolysis Using Zinc-Air Batteries with Current Regulative Diodes

    Science.gov (United States)

    Kamata, Masahiro; Paku, Miei

    2007-01-01

    Current regulative diodes (CRDs) are applied to develop new educational experiments on Faraday's law by using a zinc-air battery (PR2330) and a resistor to discharge it. The results concluded that the combination of zinc-air batteries and the CRD array is simpler, less expensive, and quantitative and gives accurate data.

  9. Current and Future Developments in Air Traffic Control

    Science.gov (United States)

    Jackson, Joseph; Green, Steven M.

    1999-01-01

    Current and future energy demands, end uses, and cost used to characterize typical applications services in the industrial sector of the United States are examined. A review and evaluation of existing industrial energy data bases was undertaken to assess their potential for supporting SERI research market suitability analysis; (2) market development; (3) end use matching; (4) industrial application studies; and (5) identification of cost and performance goals for solar systems and typical information requirements for industrial energy end use. The focus was on fuels and electric energy used for heat and power purchased by the manufacturing subsector and listed by 2, 3, and 4 digit SIC, primary fuel. The effects of federal and state industrial energy conservation programs on future industrial sector demands were assessed.

  10. Transport, deposition, and liftoff in laboratory density currents composed of hot particles in air

    Science.gov (United States)

    Andrews, B. J.; Manga, M.

    2010-12-01

    Understanding the dynamics of transport, deposition, and air entrainment in pyroclastic density currents (PDCs) is required for accurate predictions of future current behaviors and interpretations of ancient deposits, but directly observing the interiors of natural PDCs is effectively impossible. We model PDCs with scaled, hot, particle-laden density currents generated in a 6 m long, 0.6 m wide, 1.8 m tall air-filled tank. Comparison of relevant scaling between our experiments and natural PDCs indicates that we are accurately capturing much of the dynamics of dilute PDCs: * Reynolds numbers of our experiments are lower than natural currents, 10^3 compared to 10^6, but still fully turbulent; * Densimetric and Thermal Richardson numbers are of O(1) in both natural and modeled currents; * Stokes and settling numbers for particles in the experiments fall within the expected range for natural PDCs. Conditions within the tank are monitored with temperature and humidity probes. Experiments are illuminated with sheet lighting, and recorded with high-definition video cameras. In general, currents have average velocities of 10-20 cm/s, initial thicknesses of 10-20 cm (although thickness greatly increases as currents entrain and expand air), and run out or lift off distances of 3-5 m. Large Kelvin-Helmholtz type eddies usually form along the top of the current immediately behind the head; these vortices are similar in size to the total current thickness. In currents that lift off, the distal current end typically retreats with time. Preliminary results suggest that lift off distance decreases with increasing thermal Richardson number. Analysis of turbulent structures indicates that the current heads are dominated by large coherent structures with length scales, L, comparable to the current thickness. Within 5-10 L of the current fronts, sequences of similar large eddies often occur. At greater distances behind the current fronts, turbulent structures become smaller and less

  11. What's All the Talc About? Air Entrainment in Dilute Pyroclastic Density Currents

    Science.gov (United States)

    Marshall, B. J.; Andrews, B. J.; Fauria, K.

    2015-12-01

    A quantitative understanding of air entrainment is critical to predicting the behaviors of dilute Pyroclastic Density Currents (PDCs), including runout distance, liftoff, and mass fractionation into co-PDC plumes. We performed experiments in an 8.5x6x2.6 meter tank using 20 micron talc powder over a range of conditions to describe air entrainment as a function of temperature, duration and mass flux. The experiments are reproducible and are scaled with respect to the densimetric and thermal Richardson numbers (Ri and RiT), Froude number, thermal to kinetic energy density ratio (TEb/KE), Stokes number, and Settling number, such that they are dynamically similar to natural dilute PDCs. Experiments are illuminated with a swept laser sheet and imaged at 1000 Hz to create 3D reconstructions of the currents, with ~1-2 cm resolution, at up to 1.5 Hz. An array of 30 high-frequency thermocouples record the precise temperature in the currents at 3 Hz. Bulk entrainment rates are calculated based on measured current volumes, surface areas, temperatures and velocities. Entrainment rates vary from ~0-0.9 and do not show simple variation with TEb/KE, Ri, or RiT. Entrainment does, however, increase with decreasing eruption duration and increasing mass flux. Our results suggest that current heads entrain air more efficiently than current bodies (>0.5 compared to ~0.1). Because shorter duration currents have proportionally larger heads, their bulk entrainment rates are controlled by those heads, whereas longer duration currents are dominated by their bodies. Our experiments demonstrate that air entrainment, which exerts a fundamental control on PDC runout and liftoff, varies spatially and temporally within PDCs.

  12. Shape of the current tube of a negative point-to-plane corona in air

    International Nuclear Information System (INIS)

    Results are presented from the experimental studies of a negative point-to-plane air corona discharge with controlled geometry. It is shown that, in a certain range of parameters, the steady-state current-voltage characteristic of the corona can be fitted by a parabola. The results obtained are used to determine the time-averaged shape of the current tube of a negative corona

  13. Current-voltage characteristics of dc corona discharges in air between coaxial cylinders

    International Nuclear Information System (INIS)

    This paper presents the experimental measurement and numerical analysis of the current-voltage characteristics of dc corona discharges in air between coaxial cylinders. The current-voltage characteristics for both positive and negative corona discharges were measured within a specially designed corona cage. Then the measured results were fitted by different empirical formulae and analyzed by the fluid model. The current-voltage characteristics between coaxial cylinders can be expressed as I = C(U − U0)m, where m is within the range 1.5–2.0, which is similar to the point-plane electrode system. The ionization region has no significant effect on the current-voltage characteristic under a low corona current, while it will affect the distribution for the negative corona under a high corona current. The surface onset fields and ion mobilities were emphatically discussed

  14. Numerical simulation and experimental validation of a direct current air corona discharge under atmospheric pressure

    Institute of Scientific and Technical Information of China (English)

    Liu Xing-Hua; He Wei; Yang Fan; Wang Hong-Yu; Liao Rui-Jin; Xiao Han-Guang

    2012-01-01

    Air corona discharge is one of the critical problems associated with high-voltage equipment.Investigating the corona mechanism plays a key role in enhancing the electrical insulation performance.An improved self-consistent multi-component two-dimensional plasma hybrid model is presented for the simulation of a direct current atmospheric pressure corona discharge in air.The model is based on plasma hydrodynamic and chemical models,and includes 12 species and 26 reactions.In addition,the photoionization effect is introduced into the model.The simulation on a bar-plate electrode configuration with an inter-electrode gap of 5.0 mm is carried out.The discharge voltage-current characteristics and the current density distribution predicted by the hybrid model agree with the experimental measurements.In addition,the dynamics of volume charged species generation,discharge current waveform,current density distribution at an electrode,charge density,electron temperature,and electric field variations are investigated in detail based on the model.The results indicate that the model can contribute valuable insights into the physics of an air plasma discharge.

  15. Numerical simulation and experimental validation of a direct current air corona discharge under atmospheric pressure

    International Nuclear Information System (INIS)

    Air corona discharge is one of the critical problems associated with high-voltage equipment. Investigating the corona mechanism plays a key role in enhancing the electrical insulation performance. An improved self-consistent multi-component two-dimensional plasma hybrid model is presented for the simulation of a direct current atmospheric pressure corona discharge in air. The model is based on plasma hydrodynamic and chemical models, and includes 12 species and 26 reactions. In addition, the photoionization effect is introduced into the model. The simulation on a bar-plate electrode configuration with an inter-electrode gap of 5.0 mm is carried out. The discharge voltage—current characteristics and the current density distribution predicted by the hybrid model agree with the experimental measurements. In addition, the dynamics of volume charged species generation, discharge current waveform, current density distribution at an electrode, charge density, electron temperature, and electric field variations are investigated in detail based on the model. The results indicate that the model can contribute valuable insights into the physics of an air plasma discharge. (physics of gases, plasmas, and electric discharges)

  16. The current distribution on the feeding probe in an air filled rectangular microstrip antenna

    DEFF Research Database (Denmark)

    Brown, K

    1989-01-01

    The current distribution on the probe and the input impedance of the rectangular air-filled microstrip antenna are calculated using the electrical-field integral equation (EFIE) formulation. A rigorous model for the coaxial line excitation is adopted which makes the formulation valid for...... electrically thick microstrip antennas. The EFIE is solved numerically using the moment method with a piecewise linear approximation of the patch current and a polynomial approximation of the probe current. It was found by numerous calculations that operating the microstrip antenna at the resonant frequency of...... the microstrip patch gives the best results with respect to the sidelobe level and cross-polar level. To validate the calculations, the impedance of the rectangular air-filled microstrip antenna was measured for the case h=6 mm and was found to agree with the calculated impedance...

  17. Current Status of Air Toxics Management and Its Strategies for Controlling Emissions in Taiwan

    Directory of Open Access Journals (Sweden)

    Wen-Tien Tsai

    2016-04-01

    Full Text Available Since the 1970s, hazardous air pollutants (HAPs, so-called air toxics, have been of great concern because they can cause serious human health effects and have adverse effects on the environment. More noticeably, some of them are known to be human carcinogens. The objective of this paper is to investigate the regulatory systems and human health effects of air toxics which have been designated by the Taiwan government under the Air Pollution Control Act. These toxic air pollutants include acutely toxic gas (i.e., ammonia, chlorine, fluorides, hydrochloric acid, hydrogen cyanide, hydrogen sulfide, nitric acid, phosphoric acid and sulfuric acid, gas containing heavy metals, and carcinogenic chemicals (including formaldehyde, vinyl chloride, asbestos and matter containing asbestos, dioxins and furans, volatile organic compounds, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls. In line with international concern about the carcinogenic risk and environmental persistence of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/PCDFs and heavy metals in recent years, the current status in monitoring and reducing the emissions of PCDDs/PCDFs from stationary sources was analyzed as a case study in the present study. Furthermore, the control strategies for reducing emissions of air toxics from stationary sources in Taiwan were also addressed.

  18. Current approaches to the diagnosis and treatment of idiopathic pulmonary fibrosis in Europe: the AIR survey

    Directory of Open Access Journals (Sweden)

    Vincent Cottin

    2014-06-01

    Full Text Available This review presents the results of the 2013 Advancing IPF Research (AIR survey, which assessed current approaches to the diagnosis and treatment of idiopathic pulmonary fibrosis (IPF by experienced physicians. A total of 149 physicians, predominantly from European countries, replied to the 28-question survey. The results of the AIR survey were compared with a similar survey of 509 French pulmonologists conducted by the French National Reference Centre and the Network of Regional Competence Centres for Rare Lung Diseases. A number of positive findings emerged from the AIR survey, including the high level of multidisciplinary team involvement in both diagnosis and management. This survey, when taken together with the French survey, suggests that there is still a need to improve earlier diagnosis of IPF.

  19. AIR-SAND BLOWING PROCESS – A RETROSPECTIVE AND CURRENT STATE

    Directory of Open Access Journals (Sweden)

    G. I. Pasyuk

    2016-01-01

    Full Text Available Information on researches and design development in the field of air-sand blowing process and creation of core-blowing installations which were carried out in 1950–1960 is provided in the article. The reference is made to the scientific centers and concrete design engineers who performed the specified activities.The essence of air-sand blowing process and the principles of its realization in core-making machines by design development and manufacture executed by the experts of NIILITAVTOPROMA (JSC BELNIILIT is briefly stated.The main ratios of the areas between elements of system the sand-blowing installation systems, the basic rules and recommendations for design and manufacture of core-making machines and equipment for them are made. The retrospective of development and improvement of design solutions of air-sand blowing process is laid out. The essence and the modern design solution of caseless option of air-sand blowing process is stated. Illustrations of standard core-making machines for production of cores in the heated equipment and with amines blow are given. Systems the air-blowing devices, hold-down unit for blast and discharge and a special design of caseless option of sand-blowing process are described.The principle of rational combination of air-blowing process and process of a purging in modern blowing technologies is designated. The current trend of transition to computer design of system the air-blowing devices and its elements is shown (reference sections for boost, ventilation, etc..

  20. Bird flight and airplane flight. [instruments to measure air currents and flight characteristics

    Science.gov (United States)

    Magnan, A.

    1980-01-01

    Research was based on a series of mechanical, electrical, and cinematographic instruments developed to measure various features of air current behavior as well as bird and airplane flight. Investigation of rising obstruction and thermal currents led to a theory of bird flight, especially of the gliding and soaring types. It was shown how a knowledge of bird flight can be applied to glider and ultimately motorized aircraft construction. The instruments and methods used in studying stress in airplanes and in comparing the lift to drag ratios of airplanes and birds are described.

  1. Sustained diffusive alternating current gliding arc discharge in atmospheric pressure air

    DEFF Research Database (Denmark)

    Zhu, Jiajian; Gao, Jinlong; Li, Zhongshan;

    2014-01-01

    Rapid transition from glow discharge to thermal arc has been a common problem in generating stable high-power non-thermal plasmas especially at ambient conditions. A sustained diffusive gliding arc discharge was generated in a large volume in atmospheric pressure air, driven by an alternating......, synchronized with simultaneously recorded current and voltage waveforms. Dynamic details of the novel non-equilibrium discharge are revealed, which is characterized by a sinusoidal current waveform with amplitude stabilized at around 200 mA intermediate between thermal arc and glow discharge, shedding light to...

  2. Impact of current policies on future air quality and health outcomes in Delhi, India

    Science.gov (United States)

    Dholakia, Hem H.; Purohit, Pallav; Rao, Shilpa; Garg, Amit

    2013-08-01

    A key policy challenge in Indian megacities is to curb high concentrations of PM2.5 and mitigate associated adverse health impacts. Using the Greenhouse Gases and Air Pollution Interactions and Synergies (GAINS) model we carry out an integrated analysis of the air quality regulations across different sectors for the city of Delhi. Our findings show that PM2.5 concentrations for Delhi will not reach the recommended national ambient air quality standards (NAAQS) even by 2030 under the current policies scenario. Adopting advanced control technologies reduces PM2.5 concentrations by about 60% and all-cause mortality by half in 2030. Climate change mitigation policies significantly reduce greenhouse gases, but have a modest impact on reducing PM2.5 concentrations. Stringent policies to control the net flow of air pollution from trans-boundary sources will play a crucial role in reducing pollution levels in Delhi city. Achieving NAAQS requires a stringent policy portfolio that combines advanced control technologies with a switch to cleaner fuels and the control of trans-boundary pollution.

  3. Characterization of dielectric barrier discharge in air applying current measurement, numerical simulation and emission spectroscopy

    CERN Document Server

    Rajasekaran, Priyadarshini; Awakowicz, Peter

    2012-01-01

    Dielectric barrier discharge (DBD) in air is characterized applying current measurement, numerical simulation and optical emission spectroscopy (OES). For OES, a non-calibrated spectrometer is used. This diagnostic method is applicable when cross-sectional area of the active plasma volume and current density can be determined. The nitrogen emission in the spectral range of 380 nm- 406 nm is used for OES diagnostics. Electric field in the active plasma volume is determined applying the measured spectrum, well-known Frank-Condon factors for nitrogen transitions and numerically- simulated electron distribution functions. The measured electric current density is used for determination of electron density in plasma. Using the determined plasma parameters, the dissociation rate of nitrogen and oxygen in active plasma volume are calculated, which can be used by simulation of the chemical kinetics.

  4. Electrode-emission effects on the saturation current in free-air ionization chamber

    International Nuclear Information System (INIS)

    The saturation current Isub(s) in a free-air parallel grid-plate ionization chamber is found to differ for positive and negative ion-collection at the plate. The difference deltaIsub(s)=(Isub(s)+-Isub(s)-) is sensitive to the metallic nature of the collector and is explained by the electron-emission due to the impact of positive ions on the electrode's metal surface. These results can be of practical interest in radiation exposure measurements and the study of electrode emission effects from the metal surfaces. (Auth.)

  5. Learning Styles of Pilots Currently Qualified in United States Air Force Aircraft

    Science.gov (United States)

    Kanske, Craig A.

    2001-01-01

    Kolb's Learning Style Inventory was used to identify the predominant learning styles of pilots currently qualified in United States Air Force aircraft. The results indicate that these pilots show a significant preference for facts and things over people and feelings. By understanding the preferred learning styles of the target population, course material can be developed that take advantage of the strengths of these learning styles. This information can be especially useful in the future design of cockpit resource management training. The training program can be developed to demonstrate both that there are different learning styles and that it is possible to take advantage of the relative strengths of each of these learning styles.

  6. Material Properties Governing Co-Current Flame Spread: The Effect of Air Entrainment

    Science.gov (United States)

    Coutin, Mickael; Rangwala, Ali S.; Torero, Jose L.; Buckley, Steven G.

    2003-01-01

    A study on the effects of lateral air entrainment on an upward spreading flame has been conducted. The fuel is a flat PMMA plate of constant length and thickness but variable width. Video images and surface temperatures have allowed establishing the progression of the pyrolyis front and on the flame stand-off distance. These measurements have been incorporated into a theoretical formulation to establish characteristic mass transfer numbers ("B" numbers). The mass transfer number is deemed as a material related parameter that could be used to assess the potential of a material to sustain co-current flame spread. The experimental results show that the theoretical formulation fails to describe heat exchange between the flame and the surface. The discrepancies seem to be associated to lateral air entrainment that lifts the flame off the surface and leads to an over estimation of the local mass transfer number. Particle Image Velocimetry (PIV) measurements are in the process of being acquired. These measurements are intended to provide insight on the effect of air entrainment on the flame stand-off distance. A brief description of the methodology to be followed is presented here.

  7. Currents trends in the application of IBA techniques to air pollution source fingerprinting and source apportionment

    International Nuclear Information System (INIS)

    Full text: IBA techniques have been used for many years to characterise fine particle air pollution. This is not new the techniques are well established. Typically 2-3 MeV protons are used to bombard thin filter papers and up to four simultaneous techniques like PIXE, PIGE, RBS and ERDA will be applied to obtain (μg/g) concentrations for elements from hydrogen to lead. Generally low volume samplers are used to sample between 20-30 m3 of air over a 24 hour period, this together with IBA's sensitivity means that concentrations down to 1 ng/m3 of air sampled can be readily achieved with only a few minutes of proton irradiation. With these short irradiation times and low sensitivities for a broad range of elements in the periodic table, large numbers of samples can be obtained and analysed very quickly and easily. At ANSTO we have used IBA methods to acquire a database of over 50,000 filters from 85 different sites through Australia and Asia, each filter has been analysed for more than 21 different chemical species. Large databases extending over many years means that modern statistical techniques like positive matrix factorisation (PMF) can be used to define well characterised source fingerprints and source contributions for a range of different fine particle air pollutants. In this paper we will discuss these PMF techniques and show how they identify both natural sources like sea spray and windblown soils as well as anthropogenic sources like automobiles, biomass burning, coal-fired power stations and industrial emissions. These data are particularly useful for Governments, EPA's and managers of pollution to better understanding pollution sources and their relative contributions and hence to better manage air pollution. Current trends are to take these IBA and PMF techniques a step further and to combine them with wind speed and back trajectory data to better pin point and identify emission sources. We show how this is now being applied on both a local

  8. Low temperature, atmospheric pressure, direct current microplasma jet operated in air, nitrogen and oxygen

    Science.gov (United States)

    Mohamed, A.-A. H.; Kolb, J. F.; Schoenbach, K. H.

    2010-12-01

    Micro-plasma jets in atmospheric pressure molecular gases (nitrogen, oxygen, air) were generated by blowing these gases through direct current microhollow cathode discharges (MHCDs). The tapered discharge channel, drilled through two 100 to 200 μm thick molybdenum electrodes separated by a 200 μm thick alumina layer, is 150 to 450 μm in diameter in the cathode and has an opening of 100 to 300 μm in diameter in the anode. Sustaining voltages are 400 to 600 V, the maximum current is 25 mA. The gas temperature of the microplasma inside the microhollow cathode varies between ~2000 K and ~1000 K depending on current, gas, and flow rate. Outside the discharge channel the temperature in the jet can be reduced by manipulating the discharge current and the gas flow to achieve values close to room temperature. This cold microplasma jet can be used for surface treatment of heat sensitive substances, and for sterilization of contaminated areas.

  9. Supershort electron beam and voluminous heavy-current air discharge at atmospheric pressure

    International Nuclear Information System (INIS)

    The conditions of the electron beam and voluminous discharge formation in the air at the atmospheric pressure and subnanosecond pulse tension front are studied. It is shown that the electron beam in the gaseous diode originates at the pulse tension front over time of ∼ 0.5 ns and has duration at the semiheight of ≤0.4 ns. The electron beam with the electrons average energy of 60-80 keV and current amplitude of ≥70 A is obtained. It is assumed that the electron beam is formed from the electron avalanches, originating in the gap on the account of the gas ionization by fast electrons at achieving the critical field between the expanding plasma cloud front and anode

  10. Interfacial friction factors for air-water co-current stratified flow in inclined channels

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Ki Yong; No, Hee Cheon [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1997-12-31

    The interfacial shear stress is experimentally investigated for co-current air-water stratified flow in inclined rectangular channels having a length of 1854mm, width of 120 mm and height of 40mm at almost atmospheric pressure. Experiments are carried out in several inclinations from 0 deg up to 10 deg. The local film thickness and the wave height are measured at three locations, i.e., L/H = 8,23, and 40. According to the inclination angle, the experimental data are categorized into two groups; nearly horizontal data group (0 deg {<=} {theta} {<=} 0.7 deg), and inclined channel data group (0.7 deg {<=} {theta} {<=} 10 deg ). Experimental observations for nearly horizontal data group show that the flow is not fully developed due to the water level gradient and the hydraulic jump within the channel. For the inclined channel data group, a dimensionless wave height, {Delta}h/h, is empirically correlated in terms of Re{sub G} and h/H. A modified root-mean-square wave height is proposed to consider the effects of the interfacial and wave propagation velocities. It is found that an equivalent roughness has a linear relationship with the modified root-mean-square wave height and its relationship is independent of the inclination. 10 refs., 6 figs., 1 tab. (Author)

  11. Occurrence of currently used pesticides in ambient air of Centre Region (France)

    Science.gov (United States)

    Coscollà, Clara; Colin, Patrice; Yahyaoui, Abderrazak; Petrique, Olivier; Yusà, Vicent; Mellouki, Abdelwahid; Pastor, Agustin

    2010-10-01

    Ambient air samples were collected, from 2006 to 2008 at three rural and two urban sites in Centre Region (France) and analyzed for 56 currently used pesticides (CUPs), of which 41 were detected. The four CUPs most frequently detected were the herbicides trifluralin, acetochlor and pendimethalin and the fungicide chlorothalonil, which were found with frequencies ranging between 52 and 78%, and with average concentrations of 1.93, 1.32, 1.84 and 12.15 ng m -3, respectively. Among the detected pesticides, concentrations of eight fungicides (spiroxamine, fenpropimorph, cyprodinil, tolyfluanid, epoxiconazole, vinchlozolin, fluazinam, fludioxinil), two insecticides (propargite, ethoprophos), and one herbicide (oxyfluorfen) are, to our knowledge, reported for the first time in the literature. The majority of the CUPs showed a seasonal trend, with most of the detections and the highest concentrations occurring during the spring and early summer. The most important pesticides detected were related to arable crops and fruit orchards, the main cultures in this region, highlighting the fact that the main sources come from local applications. Minor differences were found in the profiles of pesticides within rural areas and between rural and urban areas.

  12. Biannual INLA conference in Buenos Aires. Current subjects of nuclear law; INLA-Tagung in Buenos Aires. Entwicklungen im Atomrecht

    Energy Technology Data Exchange (ETDEWEB)

    Raetzke, Christian [CONLAR Consulting on Nuclear Law and Regulation, Leipzig (Germany)

    2014-12-15

    The biannual conference of the International Nuclear Law Association (INLA) took place from 20 to 23 October in Buenos Aires, Argentina. The various sessions covered all relevant subjects of international nuclear law such as safety and licensing, security and safeguards, waste and decommissioning, new build, nuclear third party liability, radiation protection and transport. The article briefly discusses some developments which became apparent in the sessions on new build, on liability and on waste and decommissioning. Generally, it becomes more and more apparent that nuclear law benefits from a comparison of different national approaches and from greater harmonization, since the challenges and issues are often the same in different countries. The discussion between nuclear law experts from all over the world within INLA is an important element of this international cooperation and alignment.

  13. Indoor air quality: Carbon monoxide, molds and beyond. Current issue paper number 198

    International Nuclear Information System (INIS)

    This paper provides an overview of several of the major indoor air pollutants and some of the ways in which indoor air quality is addressed by governments in the United States and Canada. The emphasis is on non-industrial settings. Pollutants discussed include carbon dioxide, tobacco smoke, radon, carbon monoxide, nitrogen dioxide, wood smoke and particles, volatile organic compounds, and molds

  14. Are current levels of air pollution in England too high?: the impact of pollution on population mortality

    OpenAIRE

    Henderson, John; Janke, Katharina; Propper, Carol

    2007-01-01

    We examine the relationship between common sources of airborne pollution and population mortality in present day England. The current air quality limit values are low by both historical and international standards, and these are set at levels which are believed not to be harmful to health. We assess whether this view is correct. We use data at local authority level for the period 1998 to 2004 to examine whether current levels of airborne pollution, as measured by annual mean concentrations of...

  15. Long Term Stability Investigation of Solid Oxide Electrolysis Cell with Infiltrated Porous YSZ Air Electrode Under High Current

    DEFF Research Database (Denmark)

    Veltzé, Sune; Ovtar, Simona; Simonsen, Søren Bredmose; Thydén, Karl Tor Sune; Kiebach, Wolff-Ragnar; Küngas, Rainer

    stabilised zirconia (YSZ) backbone air electrode and Ni/YSZ cermet fuel electrode. The SOC was tested at electrolysis conditions under high current (up to -1 A/cm2). The porous YSZ electrodes was infiltrated with gadolinium-doped ceria oxide (CGO), to act as a barrier layer between the catalyst and the...

  16. Current status of ceramic-based membranes for oxygen separation from air.

    Science.gov (United States)

    Hashim, Salwa Meredith; Mohamed, Abdul Rahman; Bhatia, Subhash

    2010-10-15

    There has been tremendous progress in membrane technology for gas separation, in particular oxygen separation from air in the last 20 years. It provides an alternative route to the existing conventional separation processes such as cryogenic distillation and pressure swing adsorption as well as cheaper production of oxygen with high purity. This review presents the recent advances of ceramic membranes for the separation of oxygen from air at high temperature. It covers the issues and problems with respect to the selectivity and separation performance. The paper also presents different approaches applied to overcome these challenges. The future directions of ceramic-based membranes for oxygen separation from air are also presented. PMID:20813344

  17. Onset conditions for positive direct current corona discharges in air under the action of photoionization

    Science.gov (United States)

    Zheng, Yuesheng; Zhang, Bo; He, Jinliang

    2011-12-01

    This paper presents a numerical model for the inception of positive dc corona discharges in air near cylindrical anodes, which plays a bridge role between the classic positive corona onset criterion and the photoionization model considering the effective radiation wavelength. The predicted onset voltages agree well with Peek's experimental data in a wide range of conductor radii and relative air densities. The influence of the collisional quenching of emitting excited states on the surface onset field is significant with low air density or small conductor radius. Within the effective radiation wavelength, numerical expressions for the photon absorption coefficient in air and Townsend's second coefficient due to photoionization are deduced on the basis of the new model. A different perspective on the classic coefficients is given.

  18. Air

    Science.gov (United States)

    ... house) Industrial emissions (like smoke and chemicals from factories) Household cleaners (spray cleaners, air fresheners) Car emissions (like carbon monoxide) *All of these things make up “particle pollution.” They mostly come from cars, trucks, buses, and ...

  19. Exposure information in environmental health research: Current opportunities and future directions for particulate matter, ozone, and toxic air pollutants

    Energy Technology Data Exchange (ETDEWEB)

    McKone, Thomas E.; Ryan, P. Barry; Ozkaynak, Haluk

    2007-02-01

    Understanding and quantifying outdoor and indoor sources of human exposure are essential but often not adequately addressed in health-effects studies for air pollution. Air pollution epidemiology, risk assessment, health tracking and accountability assessments are examples of health-effects studies that require but often lack adequate exposure information. Recent advances in exposure modeling along with better information on time-activity and exposure factors data provide us with unique opportunities to improve the assignment of exposures for both future and ongoing studies linking air pollution to health impacts. In September 2006, scientists from the US Environmental Protection Agency (EPA) and the Centers for Disease Control and Prevention (CDC) along with scientists from the academic community and state health departments convened a symposium on air pollution exposure and health in order to identify, evaluate, and improve current approaches for linking air pollution exposures to disease. This manuscript presents the key issues, challenges and recommendations identified by the exposure working group, who used cases studies of particulate matter, ozone, and toxic air pollutant exposure to evaluate health-effects for air pollution. One of the over-arching lessons of this workshop is that obtaining better exposure information for these different health-effects studies requires both goal-setting for what is needed and mapping out the transition pathway from current capabilities to meeting these goals. Meeting our long-term goals requires definition of incremental steps that provide useful information for the interim and move us toward our long-term goals. Another over-arching theme among the three different pollutants and the different health study approaches is the need for integration among alternate exposure assessment approaches. For example, different groups may advocate exposure indicators, biomonitoring, mapping methods (GIS), modeling, environmental media

  20. Review of current and anticipated regulations on air protection in the Czech Republic

    Energy Technology Data Exchange (ETDEWEB)

    Jilek, P.; Novotny, V. [Ministry of the Environment of the Czech Republic, Prague (Czechoslovakia)

    1995-12-01

    Environmental issues, especially the solution of the air pollution problem, have taken on great significance in the Czech Republic (which was a part of the Czech and Slovak Federal Republic until the end of 1992) since the 1989 {open_quotes}Velvet{close_quotes} Revolution. The former CSFR Federal Committee for the Environment and both the Republic Ministries started immediately with creating new environmental legislation, which is the main governmental tool for protecting the environment in the newly developing democracy state system with a market oriented economy. The inspiration for that activity was found in legislation of developed countries - member states of the European Union, and in German environmental law in particular. This paper surveys the major laws and regulations that gradually came into force in the Czech Republic since 1990. The provisions of the primary significance are the Act No.309/1991 S.B., dated July 9, 1991, on the protection of the air against pollutants - The Clean Air Act, the Act No.218/1992 S.B., dated April 27, 1992, which changes and supplements the Act No.309 - The Clean Air Act, the Measure of the Federal Committee for the Environment of October 1, 1991 to the Clean Air Act, and its amended wordings of June 23, 1992, 84/1991 S.B., and 84/1992 S.B., the Act No.389/1991 S.B., dated September 10, 1991 on the state administration of air protection and charges for the pollution of air, and several regulations based on the Act No.389/1991 S.B., issued in the period 1992 -1993.

  1. Air

    International Nuclear Information System (INIS)

    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.)

  2. Unmanned air/ground vehicles heterogeneous cooperative techniques:Current status and prospects

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Multiple unmanned air/ground vehicles heterogeneous cooperation is a novel and challenging filed.Heterogeneous cooperative techniques can widen the application fields of unmanned air or ground vehicles,and enhance the effectiveness of implementing detection,search and rescue tasks.This paper mainly focused on the key issues in multiple unmanned air/ground vehicles heterogeneous cooperation,including heterogeneous flocking,formation control,formation stability,network control,and actual applications.The main problems and future directions in this field were also analyzed in detail.These innovative technologies can significantly enhance the effectiveness of implementing complicated tasks,which definitely provide a series of novel breakthroughs for the intelligence,integration and advancement of future robot systems.

  3. Lithium-air batteries: survey on the current status and perspectives towards automotive applications from a battery industry standpoint

    Energy Technology Data Exchange (ETDEWEB)

    Park, Myounggu; Sun, Heeyoung; Lee, Hyungbok; Lee, Junesoo [Battery R and D, SK Innovation, Wonchon-dong, Yuseong-gu, Daejeon (Korea, Republic of); Cho, Jaephil [Interdisciplinary School of Green Energy, Ulsan National Institute of Science and Technology (UNIST), Ulsan (Korea, Republic of)

    2012-07-15

    Li-air rechargeable batteries theoretically have advantages from both secondary batteries and fuel cells, which can be viewed as the best technological blends for automotive applications resolving the so called mileage anxiety problem due to the limited driving range of electrical vehicles based upon Li-ion batteries; this problem is rooted in the intrinsically small energy density of Li-ion batteries. This very scientific trait of Li-air batteries, which is apparently suited to the requirements of batteries for future electric vehicles, has induced quite a strong surge of research recently. This occurrence has motivated the authors to undertake a thorough review in an effort to understand the current status of Li-air battery related technologies. A comprehensive survey from a battery industry standpoint has been conducted on the fundamentals of chemistry, utilized Li-air cell configurations (or types) vs. performance, and major components comprising Li-air batteries using various sources of previously published peer-reviewed journal papers, book chapters, patents, and industrial reports. The survey results are presented here. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Current status of bird pest species in agroecosystems of Buenos Aires province, central Argentina

    OpenAIRE

    Codesido, M.; Bilenca, D.

    2011-01-01

    We carried out the first assessment of abundance and distribution of bird pest species (eared dove Zenaida auriculata, monk parakeet Myiopsitta monachus, picazuro pigeon Patagioenas picazuro and spot-winged pigeon P. maculosa) in the pampas of Buenos Aires province, Argentina, and analyzed their association with the presence of crops and/or introduced exotic woodlots in the rural landscape. We surveyed 35 transects located along secondary roads. Bird pest abundance was significantly higher at...

  5. Current saturation in free-air ionization chambers with chopped synchrotron radiation

    International Nuclear Information System (INIS)

    An expression for ion recombination in free-air ionization chambers irradiated by chopped X-rays is presented. The expression is validated by comparison with experiments using synchrotron radiation. Saturation curves for free-air ionization chambers with electrode gap widths of 4.2, 8.4 and 18 mm were obtained for 10 and 15 keV undulator synchrotron radiation thinned with a 230 Hz rotating-disk chopper. Ion recombination in free-air ionization chambers was found to be inversely proportional to the applied electric field, and an expression that satisfactorily reproduced the ion-recombination rate is determined. A comparison of the expressions for continuous and pulsed X-rays revealed that chopped high-intensity X-rays require a higher voltage to attain saturation when the product of the pulse width and electric field exceeds a value that depends on the X-ray energy. This behaviour was observed explicitly for 10 keV X-rays in measurements with the ionization chamber placed before and after the chopper

  6. Effect of electrical current on the tribological behavior of the Cu-WS2-G composites in air and vacuum

    Science.gov (United States)

    Qian, Gang; Feng, Yi; Li, Bin; Huang, Shiyin; Liu, Hongjuan; Ding, Kewang

    2013-03-01

    As the traditional graphite-based composites cannot meet the requirement of rapid developing modern industry, novel sliding electrical contact materials with high self-lubricating performance in multiple environments are eagerly required. Herein a copper-based composite with WS2 and graphite as solid lubricant are fabricated by powder metallurgy hot-pressed method. The friction and wear behaviors of the composites with and without current are investigated under the condition with sliding velocity of 10 m/s and normal load of 2.5 N/cm2 in both air and vacuum. Morphologies of the worn surfaces are observed by optical microscope and compositions of the lubricating films are analyzed by XPS. Surface profile curves and roughness of the worn surfaces are obtained by 2205 surface profiler. The results of wear tests show that the friction coefficient and wear volume loss of the composites with current are greater than that without current in both air and vacuum due to the adverse effects of electrical current which damaged the lubricating film partially and roughed the worn surfaces. XPS results demonstrate that the lubricating film formed in air is composed of oxides of Cu, WS2, elemental S and graphite, while the lubricating film formed in vacuum is composed of Cu, WS2 and graphite. Because of the synergetic lubricating action of oxides of Cu, WS2 and graphite, the composites show low friction coefficient and wear volume loss in air condition. Owing to the fact that graphite loses its lubricity which makes WS2 become the only lubricant, severe adhesive and abrasive wear occur and result in a high value of wear rate in vacuum condition. The formation of the lubricating film on the contact interface between the brush and ring is one of the factors which can greatly affect the wear performance of the brushes. The low contact voltage drop of the composites in vacuum condition is attributed to the high content of Cu in the surface film. This study fabricated a kind of new

  7. Characteristics of a Direct Current-driven plasma jet operated in open air

    International Nuclear Information System (INIS)

    A DC-driven plasma jet has been developed to generate a diffuse plasma plume by blowing argon into the ambient air. The plasma plume, showing a cup shape with a diameter of several centimeters at a higher voltage, is a pulsed discharge despite a DC voltage is applied. The pulse frequency is investigated as a function of the voltage under different gap widths and gas flow rates. Results show that plasma bullets propagate from the hollow needle to the plate electrode by spatially resolved measurement. A supposition about non-electroneutral trail of the streamer is proposed to interpret these experimental phenomena

  8. Quantitative characterization of a dielectric barrier discharge in air applying non-calibrated spectrometer, current measurement and numerical simulation

    International Nuclear Information System (INIS)

    A non-calibrated spectrometer is used for quantitative characterization of a dielectric barrier discharge (DBD) in air wherein optical emission spectroscopy (OES) is completed by current measurement and numerical simulation. This diagnostic method is applicable when the cross-sectional area of the active plasma volume and the current density can be determined. The nitrogen emission in the spectral range of 330–406 nm is used for OES diagnostics. The electric field in the active plasma volume is determined by applying the measured spectrum, well-known Franck–Condon factors for nitrogen transitions and numerically simulated electron distribution functions. The measured electric current density is used for the determination of electron density in plasma. Using the determined plasma parameters, the dissociation rates of nitrogen and oxygen in active plasma volume are calculated, which can be used for the simulation of chemical kinetics. (paper)

  9. Chemical Transport and Reduced-Form Models for Assessing Air Quality Impacts of Current and Future Energy Scenarios

    Science.gov (United States)

    Adams, P. J.

    2015-12-01

    Though essential for informed decision-making, it is challenging to estimate the air quality and public health impacts associated with current and future energy generation scenarios because the analysis must address the complicated atmospheric processes that air pollutants undergo: emissions, dispersion, chemistry, and removal. Employing a chemical transport model (CTM) is the most rigorous way to address these atmospheric processes. However, CTMs are expensive from a computational standpoint and, therefore, beyond the reach of policy analysis for many types of problems. On the other hand, previously available reduced-form models used for policy analysis fall short of the rigor of CTMs and may lead to biased results. To address this gap, we developed the Estimating Air pollution Social Impacts Using Regression (EASIUR) method, which builds parameterizations that predict per-tonne social costs and intake fractions for pollutants emitted from any location in the United States. Derived from a large database of tagged CTM simulations, the EASIUR method predicts social costs almost indistinguishable from a full CTM but with negligible computational requirements. We found that the average mortality-related social costs from inorganic PM2.5 and its precursors in the United States are 150,000-180,000/t EC, 21,000-34,000/t SO2, 4,200-15,000/t NOx, and 29,000-85,000/t NH3. This talk will demonstrate examples of using both CTMs and reduced-form models for assessing air quality impacts associated with current energy production activities as well as a future deployment of carbon capture and sequestration.

  10. Biannual INLA conference in Buenos Aires. Current subjects of nuclear law

    International Nuclear Information System (INIS)

    The biannual conference of the International Nuclear Law Association (INLA) took place from 20 to 23 October in Buenos Aires, Argentina. The various sessions covered all relevant subjects of international nuclear law such as safety and licensing, security and safeguards, waste and decommissioning, new build, nuclear third party liability, radiation protection and transport. The article briefly discusses some developments which became apparent in the sessions on new build, on liability and on waste and decommissioning. Generally, it becomes more and more apparent that nuclear law benefits from a comparison of different national approaches and from greater harmonization, since the challenges and issues are often the same in different countries. The discussion between nuclear law experts from all over the world within INLA is an important element of this international cooperation and alignment.

  11. Design of experiment apparatus for testing effects of counter-current air-water flow on containment water film formation

    International Nuclear Information System (INIS)

    This paper introduces the working principle of Passive Containment Cooling System (PCS) following a design basis accident. A flat-plate test bench and the accompanying measurement system are designed to study how the counter-current air affects the water film on the containment surface. Two key experiment parameters, flat-plate spacing and probe positions, are calculated and analyzed through fluid mechanics, experimental characteristic and experience correlation. The analysis results show that the experiment plan is reasonable and feasible, and it is proper when the flat-plate spacing is 150 mm and the probe position of the first rank is 1 m away from the flat-plate upside. (authors)

  12. Air pollution control residues from waste incineration: Current UK situation and assessment of alternative technologies

    International Nuclear Information System (INIS)

    Current disposal options for APC residues in the UK and alternative treatment technologies developed world-wide have been reviewed. APC residues are currently landfilled in the UK where they undergo in situ solidification, although the future acceptability of this option is uncertain because the EU waste acceptance criteria (WAC) introduce strict limits on leaching that are difficult to achieve. Other APC residue treatment processes have been developed which are reported to reduce leaching to below relevant regulatory limits. The Ferrox process, the VKI process, the WES-PHix process, stabilisation/solidification using cementitious binders and a range of thermal treatment processes are reviewed. Thermal treatment technologies convert APC residues combined with other wastes into inert glass or glass-ceramics that encapsulate heavy metals. The waste management industry will inevitably use the cheapest available option for treating APC residues and strict interpretation and enforcement of waste legislation is required if new, potentially more sustainable technologies are to become commercially viable

  13. The current status of the GRAPES-3 extensive air shower experiment

    Science.gov (United States)

    Gupta, S. K.; Antia, H. M.; Dugad, S. R.; Goswami, U. D.; Hayashi, Y.; Iyer, A.; Ito, N.; Jagadeesan, P.; Jain, A.; Karthikeyan, S.; Kawakami, S.; Minamino, M.; Mohanty, P. K.; Morris, S. D.; Nayak, P. K.; Nonaka, T.; Oshima, A.; Rao, B. S.; Ravindran, K. C.; Tanaka, H.; Tonwar, S. C.; Grapes-3 Collaboration

    2009-12-01

    The GRAPES-3 is a dense extensive air shower array operating with ˜400 scintillator detectors and it also contains a 560 m 2 tracking muon detector ( E>1 GeV), at Ooty in India. 25% of scintillator detectors are instrumented with two fast photomultiplier tubes (PMTs) for extending the dynamic range to ˜5×10 particles m -2 . The scintillators, signal processing electronics and data recording systems were fabricated in-house to cut costs and optimize performance. The muon multiplicity distribution of the EAS is used to probe the composition of primary cosmic rays below the 'knee', with an overlap with direct measurements. Search for multi-TeV γ-rays from point sources is done with the aid of the muon detector. A good angular resolution of 0.7° at 30 TeV, is measured from the shadow of the Moon on the isotropic flux of cosmic rays. A sensitive limit on the diffuse flux of 100 TeV γ-rays is placed by using muon detector to filter the charged cosmic ray background. A tracking muon detector allows sensitive measurements on coronal mass ejections and solar flares through Forbush decrease events. We have major expansion plans to enhance the sensitivity of the GRAPES-3 experiment in the areas listed above.

  14. The current status of the GRAPES-3 extensive air shower experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S.K.; Antia, H.M.; Dugad, S.R.; Goswami, U.D. [Tata Institute of Fundamental Research, Mumbai 400005 (India); Hayashi, Y. [Graduate School of Science, Osaka City University, Osaka 558-8585 (Japan); Iyer, A. [Tata Institute of Fundamental Research, Mumbai 400005 (India); Ito, N. [Graduate School of Science, Osaka City University, Osaka 558-8585 (Japan); Jagadeesan, P.; Jain, A.; Karthikeyan, S. [Tata Institute of Fundamental Research, Mumbai 400005 (India); Kawakami, S.; Minamino, M. [Graduate School of Science, Osaka City University, Osaka 558-8585 (Japan); Mohanty, P.K.; Morris, S.D.; Nayak, P.K. [Tata Institute of Fundamental Research, Mumbai 400005 (India); Nonaka, T. [Graduate School of Science, Osaka City University, Osaka 558-8585 (Japan); Oshima, A.; Rao, B.S.; Ravindran, K.C.; Tanaka, H. [Tata Institute of Fundamental Research, Mumbai 400005 (India)

    2009-12-15

    The GRAPES-3 is a dense extensive air shower array operating with approx400 scintillator detectors and it also contains a 560 m{sup 2} tracking muon detector (E{sub m}u>1GeV), at Ooty in India. 25% of scintillator detectors are instrumented with two fast photomultiplier tubes (PMTs) for extending the dynamic range to approx5x10{sup 3} particles m{sup -2}. The scintillators, signal processing electronics and data recording systems were fabricated in-house to cut costs and optimize performance. The muon multiplicity distribution of the EAS is used to probe the composition of primary cosmic rays below the 'knee', with an overlap with direct measurements. Search for multi-TeV gamma-rays from point sources is done with the aid of the muon detector. A good angular resolution of 0.7 deg. at 30 TeV, is measured from the shadow of the Moon on the isotropic flux of cosmic rays. A sensitive limit on the diffuse flux of 100 TeV gamma-rays is placed by using muon detector to filter the charged cosmic ray background. A tracking muon detector allows sensitive measurements on coronal mass ejections and solar flares through Forbush decrease events. We have major expansion plans to enhance the sensitivity of the GRAPES-3 experiment in the areas listed above.

  15. On the physical processes ruling an atmospheric pressure air glow discharge operating in an intermediate current regime

    International Nuclear Information System (INIS)

    Low-frequency (100 Hz), intermediate-current (50 to 200 mA) glow discharges were experimentally investigated in atmospheric pressure air between blunt copper electrodes. Voltage–current characteristics and images of the discharge for different inter-electrode distances are reported. A cathode-fall voltage close to 360 V and a current density at the cathode surface of about 11 A/cm2, both independent of the discharge current, were found. The visible emissive structure of the discharge resembles to that of a typical low-pressure glow, thus suggesting a glow-like electric field distribution in the discharge. A kinetic model for the discharge ionization processes is also presented with the aim of identifying the main physical processes ruling the discharge behavior. The numerical results indicate the presence of a non-equilibrium plasma with rather high gas temperature (above 4000 K) leading to the production of components such as NO, O, and N which are usually absent in low-current glows. Hence, the ionization by electron-impact is replaced by associative ionization, which is independent of the reduced electric field. This leads to a negative current-voltage characteristic curve, in spite of the glow-like features of the discharge. On the other hand, several estimations show that the discharge seems to be stabilized by heat conduction; being thermally stable due to its reduced size. All the quoted results indicate that although this discharge regime might be considered to be close to an arc, it is still a glow discharge as demonstrated by its overall properties, supported also by the presence of thermal non-equilibrium

  16. On the physical processes ruling an atmospheric pressure air glow discharge operating in an intermediate current regime

    Energy Technology Data Exchange (ETDEWEB)

    Prevosto, L., E-mail: prevosto@waycom.com.ar; Mancinelli, B.; Chamorro, J. C.; Cejas, E. [Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto (UTN), Laprida 651, Venado Tuerto (2600), Santa Fe (Argentina); Kelly, H. [Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto (UTN), Laprida 651, Venado Tuerto (2600), Santa Fe (Argentina); Instituto de Física del Plasma (CONICET), Facultad de Ciencias Exactas y Naturales (UBA) Ciudad Universitaria Pab. I, 1428, Buenos Aires (Argentina)

    2015-02-15

    Low-frequency (100 Hz), intermediate-current (50 to 200 mA) glow discharges were experimentally investigated in atmospheric pressure air between blunt copper electrodes. Voltage–current characteristics and images of the discharge for different inter-electrode distances are reported. A cathode-fall voltage close to 360 V and a current density at the cathode surface of about 11 A/cm{sup 2}, both independent of the discharge current, were found. The visible emissive structure of the discharge resembles to that of a typical low-pressure glow, thus suggesting a glow-like electric field distribution in the discharge. A kinetic model for the discharge ionization processes is also presented with the aim of identifying the main physical processes ruling the discharge behavior. The numerical results indicate the presence of a non-equilibrium plasma with rather high gas temperature (above 4000 K) leading to the production of components such as NO, O, and N which are usually absent in low-current glows. Hence, the ionization by electron-impact is replaced by associative ionization, which is independent of the reduced electric field. This leads to a negative current-voltage characteristic curve, in spite of the glow-like features of the discharge. On the other hand, several estimations show that the discharge seems to be stabilized by heat conduction; being thermally stable due to its reduced size. All the quoted results indicate that although this discharge regime might be considered to be close to an arc, it is still a glow discharge as demonstrated by its overall properties, supported also by the presence of thermal non-equilibrium.

  17. Photoionization produced by low-current discharges in O2, air, N2 and CO2

    International Nuclear Information System (INIS)

    An analysis of gas ionization by the radiation produced in a low-current gas discharge is performed here on the basis of the comparison of measurements and the results of direct simulation of the excitation of identified extreme ultraviolet transitions, radiation transport and ionizing absorption of radiation. In unitary gases and in their mixtures with low admixtures of other gases, the ionizing radiation is generated in one electron impact by direct dissociative excitation and by direct ionizing excitation followed by a radiative transition of an excited neutral atom or ion, respectively. In N2–O2 mixtures, photoionization predominantly occurs via ionization of O2 molecules due to the absorption of the emission produced by excited N2 and, possibly, some N I, both produced by direct electron impact. The results obtained in this work provide the missing data required for performing direct numerical simulation of pre-breakdown phenomena, including the inception and propagation of coronas and creeping sparks, in the above-mentioned gases and mixtures. (paper)

  18. Experimental investigation of droplet separation in a horizontal counter-current air/water stratified flow

    International Nuclear Information System (INIS)

    A stratified counter-current two-phase gas/liquid flow can occur in various technical systems. In the past investigations have mainly been motivated by the possible occurrence of these flows in accident scenarios of nuclear light water-reactors and in numerous applications in process engineering. However, the precise forecast of flow parameters, is still challenging, for instance due to their strong dependency on the geometric boundary conditions. A new approach which uses CFD methods (Computational Fluid Dynamics) promises a better understanding of the flow phenomena and simultaneously a higher scalability of the findings. RANS methods (Reynolds Averaged Navier Stokes) are preferred in order to compute industrial processes and geometries. A very deep understanding of the flow behavior and equation systems based on real physics are necessary preconditions to develop the equation system for a reliable RANS approach with predictive power. Therefore, local highly resolved, experimental data is needed in order to provide and validate the required turbulence and phase interaction models. The central objective of this work is to provide the data needed for the code development for these unsteady, turbulent and three-dimensional flows. Experiments were carried out at the WENKA facility (Water Entrainment Channel Karlsruhe) at the Karlsruhe Institute of Technology (KIT). The work consists of a detailed description of the test-facility including a new bended channel, the measurement techniques and the experimental results. The characterization of the new channel was done by flow maps. A high-speed imaging study gives an impression of the occurring flow regimes, and different flow phenomena like droplet separation. The velocity distributions as well as various turbulence values were investigated by particle image velocimetry (PIV). In the liquid phase fluorescent tracer-particles were used to suppress optical reflections from the phase surface (fluorescent PIV, FPIV

  19. Properties and electrochemical behaviors of AuPt alloys prepared by direct-current electrodeposition for lithium air batteries

    International Nuclear Information System (INIS)

    AuPt catalyst has a prospective application in a lithium air battery because of its bi-function on catalyzing Oxygen Reduction Reaction (ORR) and Oxygen Evolution Reaction (OER). Electrodeposition is an in-situ convenient technology for catalyst preparation without chemical residue. In an acid electrolyte, AuPt alloy catalysts were electrodeposited on carbon paper. The effect of main salt concentration, electrodeposition time and current density were studied by deposit micromorphology observation, structure analyses and composition testing. Catalytic abilities of AuPt alloys were measured by cyclic voltammetry (CV) in an ionic liquid of EMI-TFSI/Li-TFSI [1- Ethyl - 3- methylimidazolium–bis (trifluoromethanesulphonyl) imide/lithium–bis (trifluoromethanesulphonyl) imide]. The electrochemical behaviors of Au, Pt and AuPt deposits were also measured. An optimized direct-current electrodeposition process of getting high active AuPt catalyst is concluded, which is an aqueous solution containing 6.7∼10 mmol · L−1 HAuCl4, 10∼13.3 mmol · L−1 H2PtCl6 and 0.5 mol · L−1 H2SO4 as the electrolyte, current density of 20mA · cm−2 and electrodeposition time of 8∼34 s. The co-deposition of AuPt alloy is an irregular co-deposition controlled by diffusion, while gold atoms enter the platinum’s crystal lattice in the structure of AuPt alloy. The increase of the concentration of H2PtCl6 in the electrolyte, the extension of the electrodeposition time or the raise of the current density can improve the content of Pt in the deposit. The clusters’ diameters of AuPt catalysts decrease to 150∼250 nm by adjusting current densities during electrodeposition

  20. Numerical study of turbulence-influence mechanism on arc characteristics in an air direct current circuit breaker

    Science.gov (United States)

    Wu, Mingliang; Yang, Fei; Rong, Mingzhe; Wu, Yi; Qi, Yang; Cui, Yufei; Liu, Zirui; Guo, Anxiang

    2016-04-01

    This paper focuses on the numerical investigation of arc characteristics in an air direct current circuit breaker (air DCCB). Using magneto-hydrodynamics (MHD) theory, 3D laminar model and turbulence model are constructed and calculated. The standard k-epsilon model is utilized to consider the turbulence effect in the arc chamber of the DCCB. Several important phenomena are found: the arc column in the turbulence-model case is more extensive, moves much more slowly than the counterpart in the laminar-model case, and shows stagnation at the entrance of the chamber, unlike in the laminar-model case. Moreover, the arc voltage in the turbulence-model case is much lower than in the laminar-model case. However, the results in the turbulence-model case show a much better agreement with the results of the breaking experiments under DC condition than in the laminar-model case, which is contradictory to the previous conclusions from the arc researches of both the low-voltage circuit breaker and the sulfur hexafluoride (SF6) nozzle. First, in the previous air-arc research of the low-voltage circuit breaker, it is assumed that the air plasma inside the chamber is in the state of laminar, and the laminar-model application gives quite satisfactory results compared with the experiments, while in this paper, the laminar-model application works badly. Second, the turbulence-model application in the arc research of the SF6-nozzle performs much better and gives higher arc voltage than the laminar-model application does, whereas in this paper, the turbulence-model application predicts lower arc voltage than the laminar-model application does. Based on the analysis of simulation results in detail, the mechanism of the above phenomena is revealed. The transport coefficients are strongly changed by turbulence, which will enhance the arc diffusion and make the arc volume much larger. Consequently, the arc appearance and the distribution of Lorentz force in the turbulence-model case

  1. Ozone generation by negative direct current corona discharges in dry air fed coaxial wire-cylinder reactors

    Energy Technology Data Exchange (ETDEWEB)

    Yehia, Ashraf [Department of Physics, Faculty of Science, Assiut University, Assiut 71516, Egypt and Department of Physics, College of Science and Humanitarian Studies in Alkharj, Salman bin Abdulaziz University, P.O. Box 83, Alkharj 11942 (Saudi Arabia); Mizuno, Akira [Department of Environmental and Life Sciences, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan)

    2013-05-14

    An analytical study was made in this paper for calculating the ozone generation by negative dc corona discharges. The corona discharges were formed in a coaxial wire-cylinder reactor. The reactor was fed by dry air flowing with constant rates at atmospheric pressure and room temperature, and stressed by a negative dc voltage. The current-voltage characteristics of the negative dc corona discharges formed inside the reactor were measured in parallel with concentration of the generated ozone under different operating conditions. An empirical equation was derived from the experimental results for calculating the ozone concentration generated inside the reactor. The results, that have been recalculated by using the derived equation, have agreed with the experimental results over the whole range of the investigated parameters, except in the saturation range for the ozone concentration. Therefore, the derived equation represents a suitable criterion for expecting the ozone concentration generated by negative dc corona discharges in dry air fed coaxial wire-cylinder reactors under any operating conditions in range of the investigated parameters.

  2. Ozone generation by negative direct current corona discharges in dry air fed coaxial wire-cylinder reactors

    International Nuclear Information System (INIS)

    An analytical study was made in this paper for calculating the ozone generation by negative dc corona discharges. The corona discharges were formed in a coaxial wire-cylinder reactor. The reactor was fed by dry air flowing with constant rates at atmospheric pressure and room temperature, and stressed by a negative dc voltage. The current-voltage characteristics of the negative dc corona discharges formed inside the reactor were measured in parallel with concentration of the generated ozone under different operating conditions. An empirical equation was derived from the experimental results for calculating the ozone concentration generated inside the reactor. The results, that have been recalculated by using the derived equation, have agreed with the experimental results over the whole range of the investigated parameters, except in the saturation range for the ozone concentration. Therefore, the derived equation represents a suitable criterion for expecting the ozone concentration generated by negative dc corona discharges in dry air fed coaxial wire-cylinder reactors under any operating conditions in range of the investigated parameters.

  3. Co-current air-water flow in downward sloping pipes: Transport of capacity reducing gas pockets in wastewater mains

    OpenAIRE

    Pothof, I.W.M.

    2011-01-01

    Air-water flow is an undesired condition in many systems for the transportation of water or wastewater. Air in storm water tunnels may get trapped and negatively affect the system. Air pockets in hydropower tunnels or sewers may cause blow-back events and inadmissible pressure spikes. Water pipes and wastewater pressure mains in particular are subject to air pocket formation in downward-sloping reaches, such as inverted siphons or terrain slopes. Air pocket accumulation causes energy losses a...

  4. Combined current and temperature mapping in an air-cooled, open-cathode polymer electrolyte fuel cell under steady-state and dynamic conditions

    Science.gov (United States)

    Meyer, Q.; Ronaszegi, K.; Robinson, J. B.; Noorkami, M.; Curnick, O.; Ashton, S.; Danelyan, A.; Reisch, T.; Adcock, P.; Kraume, R.; Shearing, P. R.; Brett, D. J. L.

    2015-11-01

    In situ diagnostic techniques provide a means of understanding the internal workings of fuel cells so that improved designs and operating regimes can be identified. Here, for the first time, a combined current density and temperature distributed measurement system is used to generate an electro-thermal performance map of an air-cooled, air-breathing polymer electrolyte fuel cell stack operating in an air/hydrogen cross-flow configuration. Analysis is performed in low- and high-current regimes and a complex relationship between localised current density, temperature and reactant supply is identified that describes the way in which the system enters limiting performance conditions. Spatiotemporal analysis was carried out to characterise transient operations in dead-ended anode/purge mode which revealed extensive current density and temperature gradients.

  5. Co-current air-water flow in downward sloping pipes: Transport of capacity reducing gas pockets in wastewater mains

    NARCIS (Netherlands)

    Pothof, I.W.M.

    2011-01-01

    Air-water flow is an undesired condition in many systems for the transportation of water or wastewater. Air in storm water tunnels may get trapped and negatively affect the system. Air pockets in hydropower tunnels or sewers may cause blow-back events and inadmissible pressure spikes. Water pipes an

  6. Assessing levels and seasonal variations of current-use pesticides (CUPs) in the Tuscan atmosphere, Italy, using polyurethane foam disks (PUF) passive air samplers

    International Nuclear Information System (INIS)

    Polyurethane foam disks (PUF) passive air samplers (PAS) were deployed over 4 sampling periods of 3–5-months (≥ 1 year) at ten urban and rural locations throughout the Tuscany Region. The purpose was to assess the occurrence and seasonal variations of ten current-use pesticides (CUPs). PUF disk extracts were analyzed using GC–MS. The organophosphates insecticides; chlorpyrifos (3–580 pg m−3) and chlorpyrifos-methyl (below detection limit – to 570 pg m−3) presented the highest levels in air, and showed seasonal fluctuation coinciding with the growing seasons. The relative proportion urban/(urban + rural) ranged from 0.4 to 0.7 showing no differences between urban and rural concentrations. Air back trajectories analysis showed air masses passing over agricultural fields and potentially enhancing the drift of pesticides into the urban sites. This study represents the first information regarding CUPs in the atmosphere of Tuscany region using PAS-PUF disk. - Highlights: • Current use pesticides (CUPs) were detected in the atmosphere of Tuscany, Italy. • Chlorpyrifos showed the highest concentrations in air with seasonal patterns. • CUPs levels might be influenced by agricultural activities. • No differences were detected between Urban and Rural sites. • Air mass analysis indicated the monitoring sites are influenced by local sources. - Seasonality of CUPs was measured in Tuscany, Italy. Chlorpyrifos showed the highest values. Urban and rural sites showed no differences. Agricultural activities influence CUPs levels in air

  7. Modeling and control of a proton exchange membrane fuel cell with the air compressor according to requested electrical current

    Directory of Open Access Journals (Sweden)

    Malekbala Mohammad Rahim

    2015-01-01

    Full Text Available The aim of this paper is to design and investigate the dynamic behavior of a PEM fuel cell system. Dynamic analysis of a PEM fuel cell system has been done in Matlab\\Simulink software according to electrical current that has been applied from hybrid system. In addition, dynamical fuel cell system has been explained according to oriented control that is started from air injection compressor model. Also hydrogen valve actuator has been controlled according to the compressor model. The results of the fuel cell dynamic model as well as the applied compressor model are fully validated based on the available results in the open literature. Finally, the effects of several operating parameters of the fuel cell system such as anode and cathode pressures, cell voltage, compressor voltage, compressor mass flow rate variation with respect to inlet pressure ratio, net and stack powers on the dynamic behavior of the hybrid system are investigated. The results show that the model can predict the dynamic behavior of the fuel cell system accurately and it can be used directly for any control purposes.

  8. Influence of Surface Resistivity and Temperature on Variation with Time of Current Pulses in Air at Optimum Pressure

    Directory of Open Access Journals (Sweden)

    S.G. Pimpale

    1977-04-01

    Full Text Available The variation of discharge current pulses with the surface nature of electrodes has been investigated by producing discharge in the intense ionizing zone of two ozonizers (A&B containing pure, dry air at a pressure of 4 & 10mm of mercury respectively. The course of reaction in the tube A showed that the periodic rise and fall of discharge counts through a series of recurrences whose amplitude varied randomly. During this reaction, steady potential, temperature of the electrolytic bath, counting time and pulse height were kept fixed. The phenomenon obtained for both the tubes is produced within a critical range of conditions. The results have been interpreted on the basis of activated adsorption at a temperature of 90 degree and 100 degree Centigrade and discussed on the theoretical grounds of change of surface resistivity upon the glass walls. Use of different coatings on annular surface in the same system with appropriate levels of electrolytic solution for a definite value of height-pulses and temperature, etc. shows significant variations in the discharge counts.

  9. A theoretical analysis of the response of an air-cored eddy current coil for remote oxide thickness measurements on reactor components

    International Nuclear Information System (INIS)

    It is shown how the impedance of an air-cored eddy current coil in close proximity to an oxidised steel component may be calculated. Representative values were selected for the oxide thickness, lift off, operating frequency, conductivities and permeabilities of the oxide coating and steel base. The values of these parameters in the calculations were allowed to vary between suitable limits to quantify the effect of each one on coil impedance. The results of the calculations are used to determine the most suitable conditions for the measurement of oxide thickness on steel components using an air-cored eddy current probe. (author)

  10. Air Pollution Exposure and Physical Activity in China: Current Knowledge, Public Health Implications, and Future Research Needs

    Directory of Open Access Journals (Sweden)

    Jiaojiao Lü

    2015-11-01

    Full Text Available Deteriorating air quality in China has created global public health concerns in regard to health and health-related behaviors. Although emerging environmental regulations address ambient air pollution in China, the level of enforcement and long-term impact of these measures remain unknown. Exposure to air pollution has been shown to lead to multiple adverse health outcomes, including increased rates of heart disease and mortality. However, a lesser-known but increasingly significant concern is the relationship between air pollution and its effects on outdoor exercise. This is especially important in China, which has a culturally rooted lifestyle that encourages participation in outdoor physical activity. This article evaluates the intersection of air pollution and outdoor exercise and provides a discussion of issues related to its public health impact in China, where efforts to promote a healthy lifestyle may be adversely affected by the ambient air pollution that has accompanied rapid economic development and urbanization.

  11. Air Pollution Exposure and Physical Activity in China: Current Knowledge, Public Health Implications, and Future Research Needs

    OpenAIRE

    Jiaojiao Lü; Leichao Liang; Yi Feng; Rena Li; Yu Liu

    2015-01-01

    Deteriorating air quality in China has created global public health concerns in regard to health and health-related behaviors. Although emerging environmental regulations address ambient air pollution in China, the level of enforcement and long-term impact of these measures remain unknown. Exposure to air pollution has been shown to lead to multiple adverse health outcomes, including increased rates of heart disease and mortality. However, a lesser-known but increasingly significant concern i...

  12. Current Applications of OMI Tropospheric NO2 Data for Air Quality and a Look to the Future

    Science.gov (United States)

    Pickering, Kenneth E.; Bucsela, E.; Allen, D.; Prados, A.; Gleason, J.; Kondragunta, S.

    2010-01-01

    Ozone Monitoring Instrument (OMI) Tropospheric NO2 products are being used to enhance the ability to monitor changes in NO2 air quality, update emission inventories, and evaluate regional air quality models. Trends in tropospheric column NO2 have been examined over the eastern United States in relation to emissions changes mandated by regulatory actions. Decreases of 20 to 40 percent over the period 2005 to 2008 were noted, largely in response to major emission reductions at power plants. The OMI data have been used to identify regions in which the opposite trend has been found. We have also used OMI NO2 in efforts to improve emission inventories for NOx emissions from soil. Lightning NOx emissions have been added to CMAQ, the US Environmental Protection Agency's regional air quality model. Evaluation of the resulting NO2 columns in the model is being conducted using the OMI NO2 observations. Community Multiscale Air Quality (CMAQ) together with the OMI NO2 data comprise a valuable tool for monitoring and predicting air quality. Looking to the future, we expect that the combination of Global Ozone Monitoring Experiment-2 (GOME-2) (morning) and OMI (afternoon) data sets obtained through use of the same retrieval algorithms will substantially increase the possibility of successful integration of satellite information into regional air quality forecast models. Farther down the road, we anticipate the Geostationary Coastal and Air Pollution Events (GEO-CAPE) platform to supply data possibly on an hourly basis, allowing much more comprehensive analysis of air quality from space.

  13. Influence of the ash content of a solid fuel on the formation of charged particles on its combustion in a current of air

    Energy Technology Data Exchange (ETDEWEB)

    Zakharov, A.G.; Fialkov, B.S.; Khvan, L.A.; Mel' nichuk, A.Yu.

    1982-01-01

    An increase in the ash content of a fuel leads to a linear decrease in the amount of charges generated on its combustion. In the combustion of a fuel in a current of air, charged particles are generated in processes taking place on the interaction of the carbon with oxygen.

  14. The impact of shipping emissions on air pollution in the greater North Sea region - Part 1: Current emissions and concentrations

    Science.gov (United States)

    Aulinger, A.; Matthias, V.; Zeretzke, M.; Bieser, J.; Quante, M.; Backes, A.

    2016-01-01

    The North Sea is one of the areas with the highest ship traffic densities worldwide. At any time, about 3000 ships are sailing its waterways. Previous scientific publications have shown that ships contribute significantly to atmospheric concentrations of NOx, particulate matter and ozone. Especially in the case of particulate matter and ozone, this influence can even be seen in regions far away from the main shipping routes. In order to quantify the effects of North Sea shipping on air quality in its bordering states, it is essential to determine the emissions from shipping as accurately as possible. Within Interreg IVb project Clean North Sea Shipping (CNSS), a bottom-up approach was developed and used to thoroughly compile such an emission inventory for 2011 that served as the base year for the current emission situation. The innovative aspect of this approach was to use load-dependent functions to calculate emissions from the ships' current activities instead of averaged emission factors for the entire range of the engine loads. These functions were applied to ship activities that were derived from hourly records of Automatic Identification System signals together with a database containing the engine characteristics of the vessels that traveled the North Sea in 2011. The emission model yielded ship emissions among others of NOx and SO2 at high temporal and spatial resolution that were subsequently used in a chemistry transport model in order to simulate the impact of the emissions on pollutant concentration levels. The total emissions of nitrogen reached 540 Gg and those of sulfur oxides 123 Gg within the North Sea - including the adjacent western part of the Baltic Sea until 5° W. This was about twice as much of those of a medium-sized industrialized European state like the Netherlands. The relative contribution of ships to, for example, NO2 concentration levels ashore close to the sea can reach up to 25 % in summer and 15 % in winter. Some hundred kilometers

  15. 容积式空压机用空气滤清器技术水平现状综述%Overview of Current Technical Level of Air Filter for Displacement Air Compressor

    Institute of Scientific and Technical Information of China (English)

    谭强

    2012-01-01

    评述空压机用空气滤清器的作用,对压缩机机组能效水平\\辅助部件的性能和寿命的影响;对比国内空气压缩机产品技术标准中对空气滤清器的性能和技术要求;概述当前空气滤清器主导产品的使用现状,以及空气滤清器产品标准和试验标准的现状;列出压缩机用空气滤清器要求进行规范化管理的技术条款.期望建立健全压缩机行业空气滤清器产品的技术标准和验收准则,满足压缩机制造厂和最终用户的要求.%This paper reviews the function of air filter for air compressor,the effect on compressor unit energy efficiency level,and the effect on performance and service life of auxiliary parts of the compressor, and contrasts the performance and technical requirements of air filter in domestic air compressor product technical standards and summarizes the current application situation of leading air filter products and the present situation of air filter product standards and test standards.This paper lists the technical items for standardized management of compressor air filter.It is expected to establish and perfect the air filter product technical standards and acceptance criteria of the compressor industry,to meet the compressor manufacturers and end-users requirements.

  16. Indoor climate and air quality . Review of current and future topics in the field of ISB study group 10

    Science.gov (United States)

    Höppe, P.; Martinac, Ivo

    In industrialized countries about 90% of the time is spent indoors. The ambient parameters affecting indoor thermal comfort are air temperature and humidity, air velocity, and radiant heat exchange within an enclosure. In assessing the thermal environment, one needs to consider all ambient parameters, the insulating properties of the occupants' clothing, and the activity level of the occupants by means of heat balance models of the human body. Apart from thermal parameters, air quality (measured and perceived) is also of importance for well-being and health in indoor environments. Pollutant levels are influenced by both outdoor concentrations and by indoor emissions. Indoor levels can thus be lower (e.g. in the case of ozone and SO2) or higher (e.g. for CO2 and formaldehyde) than outdoor levels. Emissions from cooking play an important role, especially in developing countries. The humidity of the ambient air has a wide range of effects on the energy and water balance of the body as well as on elasticity, air quality perception, build-up of electrostatic charge and the formation or mould. However, its effect on the indoor climate is often overestimated. While air-handling systems are commonly used for achieving comfortable indoor climates, their use has also been linked to a variety of problems, some of which have received attention within the context of ''sick building syndrome''.

  17. The interplay between a self-organized process and an environmental template: corpse clustering under the influence of air currents in ants

    OpenAIRE

    Jost, Christian; Verret, Julie; Casellas, Eric; Gautaris, Jacques; Challet, Mélanie; Lluc, Jacques; Blanco, Stéphane; Clifton, Michaël; Theraulaz, Guy

    2006-01-01

    Many spatial patterns observed in nature emerge from local processes and their interactions with the local environment. The clustering of objects by social insects represents such a pattern formation process that can be observed at both the individual and the collective level. In this paper, we study the interaction between air currents and clustering behaviour in order to address the coordinating mechanisms at the individual level that underlie the spatial pattern formation process in ...

  18. Fast and accurate two-dimensional modelling of high-current, high-voltage air-cored transformers

    International Nuclear Information System (INIS)

    This paper presents a detailed two-dimensional model for high-voltage air-cored pulse transformers of two quite different designs. A filamentary technique takes magnetic diffusion fully into account and enables the resistances and self and mutual inductances that are effective under fast transient conditions to be calculated. Very good agreement between calculated and measured results for typical transformers has been obtained in several cases, and the model is now regularly used in the design of compact high-power sources

  19. Field emission in air and space-charge-limited currents from iridium-iridium oxide tips with gaps below 100 nm

    Science.gov (United States)

    Brimley, Scott; Miller, Mark S.; Hagmann, Mark J.

    2011-05-01

    Field emission diodes made with Ir/IrO2 tips separated by gaps below 100 nm and operating in air gave currents of up to 1 μA just above 10 V and largely survived potentials up to 200 V. The current-voltage characteristics included signatures of Fowler-Nordheim emission and both coherent and incoherent space-charge limited emission, where both behaviors implied molecular-scale effective emission areas. The significant, nanoampere currents that flowed at biases below the expected bulk work functions corroborate the 0.1 eV work functions from Fowler-Nordheim analysis, and are attributed to molecular scale oxide structures and adsorbates shifting the surface Fermi level. Electron transit time analysis indicates that on average only one electron crossed the gap at a time, implying that the space-charge effects are due to self-interactions.

  20. Influence of current velocity and wind speed on air-water gas exchange in a mangrove estuary

    Science.gov (United States)

    Ho, David T.; Coffineau, Nathalie; Hickman, Benjamin; Chow, Nicholas; Koffman, Tobias; Schlosser, Peter

    2016-04-01

    Knowledge of air-water gas transfer velocities and water residence times is necessary to study the fate of mangrove derived carbon exported into surrounding estuaries and ultimately to determine carbon balances in mangrove ecosystems. For the first time, the 3He/SF6 dual tracer technique, which has been proven to be a powerful tool to determine gas transfer velocities in the ocean, is applied to Shark River, an estuary situated in the largest contiguous mangrove forest in North America. The mean gas transfer velocity was 3.3 ± 0.2 cm h-1 during the experiment, with a water residence time of 16.5 ± 2.0 days. We propose a gas exchange parameterization that takes into account the major sources of turbulence in the estuary (i.e., bottom generated shear and wind stress).

  1. Experimental and kinetic simulation studies of radio-frequency and direct-current breakdown in synthetic air

    International Nuclear Information System (INIS)

    We report a combined experimental and modeling study of the breakdown of synthetic air under the influence of static (dc) and time-varying electric fields, up to radio-frequencies (RF). The simulations of the breakdown events are based on a simplified model that makes the problem computationally tractable: only electrons are traced by Monte Carlo simulation. In the dc case the simulation is used for the determination of the effective secondary electron emission coefficient, based on the measured dc Paschen curve. In the RF case we observe a transition between the modes (i) where reproduction of the charges takes place in the gas volume (at electron oscillation amplitudes smaller than the gap size) and (ii) where surface processes—secondary electron emission and electron reflection—play an important role, as most of the oscillating electrons reach the electrode surfaces. The RF (f = 13.56 MHz) simulations, assuming a constant effective secondary electron yield, reproduce well the breakdown curve obtained in the experiment. (paper)

  2. Current analyses of problems of energy supply and air pollution control; Aktuelle Analysen zu energie- und klimapolitischen Fragen

    Energy Technology Data Exchange (ETDEWEB)

    Semrau, G. [Gesamtverbandes des deutschen Steinkohlenbergbaus, Essen (Germany)

    2001-10-11

    In an analysis of the electricity crisis in California the German Institute for Economic Research investigated the question whether similar problems could also arise in Europe. The outcome is that as a result of the liberalisation of the electricity markets in Europe the risk of temporary interruptions of supply tends to be greater and provision against contingencies is therefore advisable - in Great Britain intensive tests are currently being conducted on introduction of an emission trade system. In a recent analysis' Professor Luebbe-Wolff examined the British model and compared it with the German climate protection agreement. She concluded that there is no reason to advocate the British model and thus imply that the policy pursued hitherto in Germany is wrong. (orig.) [German] Das Deutsche Institut fuer Wirtschaftsforschung hat in einer Analyse der Stromkrise in Kalifornien die Frage untersucht, ob auch in Europa aehnliche Probleme entstehen koennten. Das Ergebnis ist, dass infolge der Liberalisierung der Strommaerkte in Europa das Risiko temporaerer Versorgungsstoerungen ohne flankierende Massnahmen eher groesser wuerde und daher Risikovorsorge geboten sei. - In Grossbritannien wird zur Zeit die Einfuehrung eines Emissionshandelssystems intensiv geprueft. In einer kuerzlich vorgelegten Analyse hat Frau Professor Luebbe-Wolff das britische Modell analysiert und der deutschen Klimaschutzvereinbarung gegenuebergestellt. Ihr Fazit: Es gibt keinen Grund, dem britischen Modell nachzueifern und damit implizit die in Deutschland bisher verfolgte Politik fuer verfehlt zu erklaeren. (orig.)

  3. Anomalous Oxide Charge Variation Identified by Alternating Current Surface Photovoltage Method in Cr-Aqueous-Solution-Rinsed p-Type Si(001) Wafers Exposed to Air

    Science.gov (United States)

    Shimizu, Hirofumi; Sanada, Yuji

    2011-11-01

    Chromium (Cr)-aqueous-solution-rinsed and/or hydrofluoric acid (HF)-solution-dipped p-type silicon (Si) (001) wafer surfaces are investigated by the frequency-dependent alternating current (AC) surface photovoltage (SPV) method. At the Cr(OH)3/p-type Si interface, in principle, a Schottky barrier could not possibly be generated. The Cr ion (Cr3+) is considered to forcibly deprive a p-type Si substrate of electrons during metallization (Cr3++3e-→Cr). Thus, at an early stage of air exposure, a positive fixed oxide charge may be compensated for by electrons, indicating the disappearance of AC SPV. With air exposure time, AC SPV emerges again and increases gradually in a Cr-deposited p-type Si(001) surface. This is because the native oxide between the Cr atom layer and the p-type Si substrate grows with time. As a result, a positive fixed oxide charge exceeds the overall charge state of the Cr-deposited p-type Si surface. Thus, AC SPV appears again and gradually increases with the fixed oxide charge in p-type Si. The saturated value is in a good agreement with that of the HF aqueous-solution-dipped p-type Si surface.

  4. Spatiotemporal variability and drivers of pCO2 and air-sea CO2 fluxes in the California Current System: an eddy-resolving modeling study

    Science.gov (United States)

    Turi, G.; Lachkar, Z.; Gruber, N.

    2014-02-01

    We quantify the CO2 source/sink nature of the California Current System (CalCS) and determine the drivers and processes behind the mean and spatiotemporal variability of the partial pressure of CO2 (pCO2) in the surface ocean. To this end, we analyze eddy-resolving, climatological simulations of a coupled physical-biogeochemical oceanic model on the basis of the Regional Oceanic Modeling System (ROMS). In the annual mean, the entire CalCS within 800 km of the coast and from ∼33° N to 46° N is essentially neutral with regard to atmospheric CO2: the model simulates an integrated uptake flux of -0.9 ± 3.6 Tg C yr-1, corresponding to an average flux density of -0.05 ± 0.20 mol C m-2 yr-1. This near zero flux is a consequence of an almost complete regional compensation between (i) strong outgassing in the nearshore region (first 100 km) that brings waters with high concentrations of dissolved inorganic carbon (DIC) to the surface and (ii) and a weaker, but more widespread uptake flux in the offshore region due to an intense biological reduction of this DIC, driven by the nutrients that are upwelled together with the DIC. The air-sea CO2 fluxes vary substantially in time, both on seasonal and sub-seasonal timescales, largely driven by variations in surface ocean pCO2. Most of the variability in pCO2 is associated with the seasonal cycle, with the exception of the nearshore region, where sub-seasonal variations driven by mesoscale processes dominate. In the regions offshore of 100 km, changes in surface temperature are the main driver, while in the nearshore region, changes in surface temperature, as well as anomalies in DIC and alkalinity (Alk) owing to changes in circulation, biological productivity and air-sea CO2 fluxes dominate. The prevalence of eddy-driven variability in the nearshore 100 km leads to a complex spatiotemporal mosaic of surface ocean pCO2 and air-sea CO2 fluxes that require a substantial observational effort to determine the source/sink nature

  5. Counter-current flow limitation in a model of the hot leg of a PWR—Comparison between air/water and steam/water experiments

    International Nuclear Information System (INIS)

    Highlights: ► Investigation of CCFL in a model of a PWR hot leg with rectangular cross-section. ► Visualisation of steam/water CCFL over large windows at reactor typical boundary conditions. ► Comparison between low pressure air experiments and high pressure steam experiments. ► Confirmation of the Wallis similarity to scale flooding in the hot leg over a wide range of boundary conditions. - Abstract: In order to investigate the two-phase flow behaviour in a complex reactor-typical geometry and to supply suitable data for computational fluid dynamics (CFD) code validation, a model of the hot leg of a pressurised water reactor was built at Helmholtz-Zentrum Dresden Rossendorf (HZDR). The hot leg model is devoted to optical measurement techniques, therefore, a flat test section design was chosen and equipped with large windows. In order to enable the operation at high pressures, the test section is installed in the pressure chamber of the TOPFLOW (Transient twO Phase FLOW) test facility of HZDR, which is used to perform the experiments under pressure equilibrium with the inside atmosphere. Counter-current flow limitation (CCFL) experiments were performed, simulating the reflux-condenser cooling mode appearing in small break loss-of-coolant-accident (LOCA) scenarios. The fluids used were air and water at room temperature and pressures of up to 3.0 bar, as well as steam and water at pressures of up to 50 bar and the corresponding saturation temperature of 264 °C. One selected 50 bar experiment is presented in detail: the observed behaviour is analysed and illustrated by typical high-speed camera images of the flow. Furthermore, the flooding characteristics obtained from the different experimental runs are presented in terms of the Wallis parameter and Kutateladze number, which are commonly used in the literature. However, a discrepancy was first observed between the air/water and steam/water series. Further investigations show that the steam was probably wet

  6. Air-water tests on counter-current flow limitation at lower end of vertical pipes simulating lower part of steam generator U-tube

    International Nuclear Information System (INIS)

    Air-water tests on counter-current flow limitation (CCFL) were carried out using vertical pipes with the diameter of D=20 mm and a sharp lower edge which simulated the lower part of U-tubes in a steam generator. Flow patterns were observed to identify the location of CCFL occurrence, and effects of the pipe length L and the water level in the upper tank h on CCFL were measured under the conditions of L=100-700 mm and h=100-600 mm. As a result, CCFL appeared at the upper end under the conditions of L/D=5 and h/D=5, but at the lower end for L/D≥15 and h/D=5∼30. In the case of the CCFL occurrence at the lower end, L and h did not affect CCFL characteristics. Using the Wallis parameters, JG* and JL*, a CCFL correlation for the sharp lower edge was derived. The CCFL constant, which is the value of JG*1/2 at JL*1/2=0, was C=0.73±0.02. (author)

  7. Primary and oxidative DNA damage in salivary leukocytes as a tool for the evaluation of air pollution early biological effects in children: current status of the MAPEC (Monitoring Air Pollution Effects on Children for supporting public health policy) study

    OpenAIRE

    Samuele Vannini; Sara Levorato; Elisabetta Ceretti; Sara Bonetta; Annalaura Carducci; Antonella De Donno; Alessio Perotti; Silvia Bonizzoni; Alberto Bonetti

    2015-01-01

    Background - Air pollution is a global problem: airborne or deposited pollutants are present everywhere on the planet, from highly polluted to remote areas. Twenty per cent of the EU urban population lives in areas where the EU air quality 24-hour limit value for particulate matter (PM10) is exceeded. At present, PM is Europe's most problematic pollutant in terms of harm to health, as reported by European Environmental Agency (EEA) in the EEA Technical Report on Air quality in Europe, 2011. A...

  8. Subsurface evaluation of the west parking lot and landfill 3 areas of Air Force Plant 4, Fort Worth, Texas, using two-dimensional direct-current resistivity profiling

    Science.gov (United States)

    Braun, Christopher L.; Jones, Sonya A.

    2002-01-01

    During September 1999, the U.S. Geological Survey made 10 two-dimensional direct-current resistivity profile surveys in the west parking lot and landfill 3 areas of Air Force Plant 4, Fort Worth, Texas, to identify subsurface areas of anomalously high or low resistivity that could indicate potential contamination, contaminant pathways, or anthropogenic structures. Six of the 10 surveys (transects) were in the west parking lot. Each of the inverted sections of these transects had anomalously high resistivities in the terrace alluvium/fill (the surficial subsurface layer) that probably were caused by highly resistive fill material. In addition, each of these transects had anomalously low resistivities in the Walnut Formation (a bedrock layer immediately beneath the alluvium/fill) that could have been caused by saturation of fractures within the Walnut Formation. A high-resistivity anomaly in the central part of the study area probably is associated with pea gravel fill used in construction of a French drain. Another high resistivity anomaly in the west parking lot, slightly southeast of the French drain, could be caused by dense nonaqueous-phase liquid in the Walnut Formation. The inverted sections of the four transects in the landfill 3 area tended to have slightly higher resistivities in both the alluvium/fill and the Walnut Formation than the transects in the west parking lot. The higher resistivities in the alluvium/fill could have been caused by drier conditions in grassy areas relative to conditions in the west parking lot. Higher resistivities in parts of the Walnut Formation also could be a function of drier conditions or variations in the lithology of the Walnut Formation. In addition to the 10 vertical sections, four horizontal sections at 2-meteraltitude intervals show generally increasing resistivity with decreasing altitude that most likely results from the increased influence of the Walnut Formation, which has a higher resistivity than the terrace

  9. The impact of shipping emissions on air pollution in the Greater North Sea region – Part 1: Current emissions and concentrations

    Directory of Open Access Journals (Sweden)

    A. Aulinger

    2015-04-01

    Full Text Available The North Sea is one of the areas with the highest ship traffic densities worldwide. At any time, about 3000 ships are sailing its waterways. Previous scientific publications have shown that ships contribute significantly to atmospheric concentrations of NOx, particulate matter and ozone. Especially in the case of particulate matter and ozone this influence can even be seen in regions far away from the main shipping routes. In order to quantify the effects of North Sea shipping on air quality in its bordering states, it is essential to determine the emissions from shipping as accurately as possible. Within the Interreg IVb project Clean North Sea Shipping (CNSS a bottom-up approach was developed and used to thoroughly compile such an emission inventory for 2011 that served as the base year for the current emission situation. The innovative aspect of this approach was to use load dependent functions to calculate emissions from the ships' current activities instead of averaged emission factors for the entire range of the engine loads. These functions were applied to ship activities that were derived from hourly records of Automatic Identification System signals together with a data base containing the engine characteristics of the vessels that traveled the North Sea in 2011. The emission model yielded ship emissions among others of NOx and SO2 in high temporal and spatial resolution that were subsequently used in a chemistry transport model in order to simulate the impact of the emissions on pollutant concentration levels. The total emissions of nitrogen reached 540 Gg and of sulfur oxides 123 Gg within the North Sea, which was about twice as much of those of a medium-sized industrialized European state like the Netherlands. The relative contribution of ships to, for example, NO2 concentration levels ashore close to the sea can reach up to 25% in summer and 15% in winter. Some hundred kilometers away from the sea the contribution was about 6% in

  10. Primary and oxidative DNA damage in salivary leukocytes as a tool for the evaluation of air pollution early biological effects in children: current status of the MAPEC (Monitoring Air Pollution Effects on Children for supporting public health policy study

    Directory of Open Access Journals (Sweden)

    Samuele Vannini

    2015-05-01

    Conclusions - The main objective of the MAPEC study is to evaluate the associations in children between air pollutants and early biological effects, and to propose a model for estimating the global genotoxic risk.

  11. Ambient Air Quality Data Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Office of Air and Radiation??s (OAR) Ambient Air Quality Data (Current) contains ambient air pollution data collected by EPA, other federal agencies, as well as...

  12. Ambient Air Quality Data Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Office of Air and Radiation's (OAR) Ambient Air Quality Data (Current) contains ambient air pollution data collected by EPA, other federal agencies, as well as...

  13. Air Quality Guide for Ozone

    Science.gov (United States)

    Local Air Quality Conditions Zip Code: State : My Current Location Air Quality Guide for Ozone Ground-level ozone is one of our nation’s most common air pollutants. Use the chart below to help reduce ...

  14. Air surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Patton, G.W.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the air surveillance and monitoring programs currently in operation at that Hanford Site. Atmospheric releases of pollutants from Hanford to the surrounding region are a potential source of human exposure. For that reason, both radioactive and nonradioactive materials in air are monitored at a number of locations. The influence of Hanford emissions on local radionuclide concentrations was evaluated by comparing concentrations measured at distant locations within the region to concentrations measured at the Site perimeter. This section discusses sample collection, analytical methods, and the results of the Hanford air surveillance program. A complete listing of all analytical results summarized in this section is reported separately by Bisping (1995).

  15. SU-E-P-15: Technique Factor Modulation and Reference Plane Air Kerma Rates in Response to Simulated Patient Thickness Variations for a Sample of Current Generation Fluoroscopes

    Energy Technology Data Exchange (ETDEWEB)

    Wunderle, K [Cleveland Clinic Foundation, Cleveland, OH& Wayne State University School of Medicine, Detroit, MI (United States); Rakowski, J [Wayne State University School of Medicine, Detroit, MI (United States); Dong, F [Cleveland Clinic Foundation, Cleveland, OH (United States)

    2015-06-15

    Purpose: To evaluate and compare approaches to technique factor modulation and air kerma rates in response to simulated patient thickness variations for four state-of-the-art and one previous-generation interventional fluoroscopes. Methods: A polymethyl methacrylate (PMMA) phantom was used as a tissue surrogate for the purposes of determining fluoroscopic reference plane air kerma rates, kVp, mA, and spectral filtration over a wide range of simulated tissue thicknesses. Data were acquired for each fluoroscopic and acquisition dose curve within a default abdomen or body imaging protocol. Results: The data obtained indicated vendor- and model-specific variations in the approach to technique factor modulation and reference plane air kerma rates across a range of tissue thicknesses. Some vendors have made hardware advances increasing the radiation output capabilities of their fluoroscopes; this was evident in the acquisition air kerma rates. However, in the imaging protocol evaluated, all of the state-of-the-art systems had relatively low air kerma rates in the fluoroscopic low-dose imaging mode as compared to the previous-generation unit. Each of the newest-generation systems also employ copper filtration in the selected protocol in the acquisition mode of imaging; this is a substantial benefit, reducing the skin entrance dose to the patient in the highest dose-rate mode of fluoroscope operation. Conclusion: Understanding how fluoroscopic technique factors are modulated provides insight into the vendor-specific image acquisition approach and provides opportunities to optimize the imaging protocols for clinical practice. The enhanced radiation output capabilities of some of the fluoroscopes may, under specific conditions, may be beneficial; however, these higher output capabilities also have the potential to lead to unnecessarily high dose rates. Therefore, all parties involved in imaging, including the clinical team, medical physicists, and imaging vendors, must work

  16. SU-E-P-15: Technique Factor Modulation and Reference Plane Air Kerma Rates in Response to Simulated Patient Thickness Variations for a Sample of Current Generation Fluoroscopes

    International Nuclear Information System (INIS)

    Purpose: To evaluate and compare approaches to technique factor modulation and air kerma rates in response to simulated patient thickness variations for four state-of-the-art and one previous-generation interventional fluoroscopes. Methods: A polymethyl methacrylate (PMMA) phantom was used as a tissue surrogate for the purposes of determining fluoroscopic reference plane air kerma rates, kVp, mA, and spectral filtration over a wide range of simulated tissue thicknesses. Data were acquired for each fluoroscopic and acquisition dose curve within a default abdomen or body imaging protocol. Results: The data obtained indicated vendor- and model-specific variations in the approach to technique factor modulation and reference plane air kerma rates across a range of tissue thicknesses. Some vendors have made hardware advances increasing the radiation output capabilities of their fluoroscopes; this was evident in the acquisition air kerma rates. However, in the imaging protocol evaluated, all of the state-of-the-art systems had relatively low air kerma rates in the fluoroscopic low-dose imaging mode as compared to the previous-generation unit. Each of the newest-generation systems also employ copper filtration in the selected protocol in the acquisition mode of imaging; this is a substantial benefit, reducing the skin entrance dose to the patient in the highest dose-rate mode of fluoroscope operation. Conclusion: Understanding how fluoroscopic technique factors are modulated provides insight into the vendor-specific image acquisition approach and provides opportunities to optimize the imaging protocols for clinical practice. The enhanced radiation output capabilities of some of the fluoroscopes may, under specific conditions, may be beneficial; however, these higher output capabilities also have the potential to lead to unnecessarily high dose rates. Therefore, all parties involved in imaging, including the clinical team, medical physicists, and imaging vendors, must work

  17. Current Situation Research of Domestic Air Conditioner Distribution Channel in Xuzhou and Analysis of Innovative Channel Mode:Setting Gree Air-co as an Example%徐州市家用空调器分销渠道现状调研及创新渠道模式探析--以格力空调为例

    Institute of Scientific and Technical Information of China (English)

    李阳; 姚君秋; 周长卿; 戎晓红

    2013-01-01

    Air conditioning manufaturers in Xuzhou are facing increasingly fierce competion. As an important inflluencing factor of sales performance, choosing of distribution channel is getting more and more attention. All air conditioning manufacturers are constantly adjusting distribution strategies and exploring new channel modes. Gree Electric Appliances, Inc. of Zhuhai is a leading company in Chinese air conditioning market. This article takes Zhuhai Gree Air-co as an example to analyse the current situation of air conditioner distribution chaanel in Xuzhou and explore channel innovation modes.%  空调厂家在徐州的竞争日趋激烈,分销渠道的选择作为影响其销售业绩的重要因素,越来越受重视。各空调厂家都在不断地调整渠道策略,探索新渠道模式。珠海格力电器股份有限公司占据着中国空调市场一线品牌的领军位置。本文以珠海格力空调为例,分析徐州市家用空调器分销渠道现状,探析渠道创新模式。

  18. Air Pollution

    Science.gov (United States)

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, dust, ... a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

  19. Air Pollution

    Science.gov (United States)

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, dust, pollen and ... Ozone, a gas, is a major part of air pollution in cities. When ozone forms air pollution, ...

  20. Current knowledge on the air quality impacts and greenhouse gas emissions of methane valorization or production facilities - Study report. Study synthesis

    International Nuclear Information System (INIS)

    The high potential of biogas activities development raises the question of the real impacts of the biogas sector. This study establishes the state of knowledge of impacts of biogas production and recovery plants on air pollutants and greenhouse gases emissions. This state of art is a statement of direct impacts (for any biogas plant, throughout his life cycle) and indirect impacts (for the particular case of agricultural biogas plants), aiming to propose technical recommendations to control air emissions and research subjects to further knowledge. To date, four priority thematic areas to deepen have been identified: ammonia and nitrous oxide emissions for the digestate recovery step, the uncontrolled emissions of methane in the biogas plant, odorous compounds emissions during feedstock storage and ammonia and methane emissions during digestate storage and treatment. Knowledge about indirect impacts is limited and does not allow to identify and quantify them into details. A mapping of the changes caused by the establishment of anaerobic digestion plant on a farm is proposed in the study. This is a methodological basis for reflection for further developments. The quantitative study of two cases of agricultural biogas plants is a first attempt to quantify the impacts, based on the lessons learned from the state of knowledge. Recommendations by step of anaerobic digestion process are proposed and analyzed according to their technical feasibility, maturity, efficiency and the level of investment needed. Finally, research subjects are presented: they aim at achieving measurement campaigns in installations which are functioning, at producing reference values and at developing methodologies of assessment of the impacts. (authors)

  1. 气流输送式条播机现状及我国应用情况分析%Analysis of Air Seed Drill Current Situations and Using Situation in China

    Institute of Scientific and Technical Information of China (English)

    杨慧; 刘立晶; 周军平; 赵郑斌; 赵金辉

    2013-01-01

    气流输送式条播机具有减少钢材使用量、增加作业幅宽和提高作业效率等优点,是未来条播机主要发展机型。为此,对气流输送式条播机的国内外技术现状、种类及在我国应用中存在的问题进行了分析。结果表明:国外气流输送式播种技术已经成熟并广泛应用,我国仅处于实验室研究阶段,试制产品还未推广应用,且对技术的理论研究很少。%Air seed drills have many advantages which can reduce the use quantity of steel , increase working width , im-prove efficiency etc .It will be the main form of future seeders .The current research status at home and abroad , classifi-cations and problems existing in China of air seed drills were analyzed .Analysis showed that the technology of air seed drills at abroad had been very successful and widely used .However , the study in China was still in laboratory stage , the product had not been applied , and it lacked of theoretical study .

  2. Air pollution

    International Nuclear Information System (INIS)

    Australian cites experience a number of current and emerging air pollution problems. Concentrations of traditional primary pollutants such as CO, lead and dust have fallen in recent years as a consequence of air pollutant control measures, and the widespread introduction of lead-free petrol. However, recommended guidelines for ozone, the principal component of photochemical smog, are regularly exceeded in major capital cities in the summer months. In addition, it is predicted that extensive urban expansion will lead to much greater dependence on the motor vehicle as the primary means of transportation. Effects of air pollution are felt at a variety of scales. Traditionally, concerns about gaseous and particulate emissions from industrial and vehicular sources were focused on local impacts due to exposure to toxic species such as CO and lead. As noted above, concentrations of these pollutants have been reduced by a variety of control measures. Pollutants which have effects at a regional scale, such as photochemically-produced ozone, and acidic gases and particles have proved more difficult to reduce. In general, these pollutants arc not the result of direct emissions to atmosphere, but result from complex secondary processes driven by photochemical reactions of species such as NO2 and aldehydes. In addition, global effects of gaseous and particulate emissions to the atmosphere have received significant recent attention, concentrations of atmospheric CO2 with predicted impacts on global climate, and ozone depletion due to anthropogenic emissions of chlorine-containing chemicals are the two major examples. Combustion processes from petrol- and diesel-fuelled vehicles, make major contributions to air pollution, and the magnitude of this contribution is discussed in this article

  3. Bad traffic, bad air

    OpenAIRE

    Duca, Edward

    2012-01-01

    Air pollution is one of Malta’s greatest concerns. Transportation is the principal source with over 300,000 vehicles belching out smoke, which damages our environment and health. Emissions from vehicles need to be monitored and controlled, and the information used to improve the current system and ensure an acceptable air quality. By using the pollution data set, Nicolette Formosa (supervised by Dr Kenneth Scerri) mapped the air pollution levels and major sources around Malta. http://www....

  4. Air Pollution and Industry.

    Science.gov (United States)

    Ross, R. D., Ed.

    This book is an authoritative reference and practical guide designed to help the plant engineer identify and solve industrial air pollution problems in order to be able to meet current air pollution regulations. Prepared under the editorial supervision of an experienced chemical engineer, with each chapter contributed by an expert in his field,…

  5. Air Abrasion

    Science.gov (United States)

    ... delivered directly to your desktop! more... What Is Air Abrasion? Article Chapters What Is Air Abrasion? What Happens? The Pros and Cons Will I Feel Anything? Is Air Abrasion for Everyone? print full article print this ...

  6. Effect of Gun Current on Deposition of CaZrO3 Coatings on SS316L by Air Plasma Spraying for Biomedical Applications

    International Nuclear Information System (INIS)

    CaZrO3 is high melting point ceramic material that is generally studied as coating for high temperature applications in aircrafts and land based power turbines. In this study 30 mol% calcia stabilized zirconia (CaZrO3) was deposited on SS316L substrate by atmospheric plasma spray (APS) technique as possible candidate for biomedical applications in orthopaedics and dentistry for medical implants. The coatings were deposited at three gun currents of 400A, 500A and 600A keeping gun to substrate distance fixed. Coatings were characterized by surface profilometery, SEM, XRD and wear tesing. Results indicate that coating deposited at 600A has highest coating thickness and highest roughness (Ra) values. Dipping the prepared coatings in simulated body fluid (SBF) exhibited precipitation of apatite as revealed by SEM and EDX analysis. The deposited coating will act as a barrier to diffusion of deleterious Ni ions from substrate to surrounding tissues and may enhance the bone in growth when implanted. (author)

  7. Experimental investigation of droplet separation in a horizontal counter-current air/water stratified flow; Experimentelle Untersuchung der Tropfenabscheidung einer horizontalen, entgegengerichteten Wasser/Luft-Schichtenstroemung

    Energy Technology Data Exchange (ETDEWEB)

    Gabriel, Stephan Gerhard

    2015-07-01

    A stratified counter-current two-phase gas/liquid flow can occur in various technical systems. In the past investigations have mainly been motivated by the possible occurrence of these flows in accident scenarios of nuclear light water-reactors and in numerous applications in process engineering. However, the precise forecast of flow parameters, is still challenging, for instance due to their strong dependency on the geometric boundary conditions. A new approach which uses CFD methods (Computational Fluid Dynamics) promises a better understanding of the flow phenomena and simultaneously a higher scalability of the findings. RANS methods (Reynolds Averaged Navier Stokes) are preferred in order to compute industrial processes and geometries. A very deep understanding of the flow behavior and equation systems based on real physics are necessary preconditions to develop the equation system for a reliable RANS approach with predictive power. Therefore, local highly resolved, experimental data is needed in order to provide and validate the required turbulence and phase interaction models. The central objective of this work is to provide the data needed for the code development for these unsteady, turbulent and three-dimensional flows. Experiments were carried out at the WENKA facility (Water Entrainment Channel Karlsruhe) at the Karlsruhe Institute of Technology (KIT). The work consists of a detailed description of the test-facility including a new bended channel, the measurement techniques and the experimental results. The characterization of the new channel was done by flow maps. A high-speed imaging study gives an impression of the occurring flow regimes, and different flow phenomena like droplet separation. The velocity distributions as well as various turbulence values were investigated by particle image velocimetry (PIV). In the liquid phase fluorescent tracer-particles were used to suppress optical reflections from the phase surface (fluorescent PIV, FPIV

  8. The law relating to air currents

    Science.gov (United States)

    1921-01-01

    Discussed here are the aerodynamics of a subdivided wing section. The emphasis is upon the increase of lift with more acute angles of attack. Also discussed are wind tunnel tests of the relations among wind resistance, lift, angle of attack, and velocity.

  9. Air movement - good or bad?

    DEFF Research Database (Denmark)

    Toftum, Jørn

    2004-01-01

    Air movement - good or bad? The question can only be answered by those who are exposed when they are exposed. Human perception of air movement depends on environmental factors including air velocity, air velocity fluctuations, air temperature, and personal factors such as overall thermal sensation...... and activity level. Even for the same individual, sensitivity to air movement may change from day to day as a result of e.g. different levels of fatigue. Based on existing literature, the current paper summarizes factors influencing the human perception of air movement and attempts to specify in...... general terms when air movement is desirable and when it is not. At temperatures up to 22-23oC, at sedentary activity and with occupants feeling neutral or cooler there is a risk of air movement being perceived as unacceptable, even at low velocities. In particular, a cool overall thermal sensation...

  10. High-Compression-Ratio; Atkinson-Cycle Engine Using Low-Pressure Direct Injection and Pneumatic-Electronic Valve Actuation Enabled by Ionization Current and Foward-Backward Mass Air Flow Sensor Feedback

    Energy Technology Data Exchange (ETDEWEB)

    Harold Schock; Farhad Jaberi; Ahmed Naguib; Guoming Zhu; David Hung

    2007-12-31

    This report describes the work completed over a two and one half year effort sponsored by the US Department of Energy. The goal was to demonstrate the technology needed to produce a highly efficient engine enabled by several technologies which were to be developed in the course of the work. The technologies included: (1) A low-pressure direct injection system; (2) A mass air flow sensor which would measure the net airflow into the engine on a per cycle basis; (3) A feedback control system enabled by measuring ionization current signals from the spark plug gap; and (4) An infinitely variable cam actuation system based on a pneumatic-hydraulic valve actuation These developments were supplemented by the use of advanced large eddy simulations as well as evaluations of fuel air mixing using the KIVA and WAVE models. The simulations were accompanied by experimental verification when possible. In this effort a solid base has been established for continued development of the advanced engine concepts originally proposed. Due to problems with the valve actuation system a complete demonstration of the engine concept originally proposed was not possible. Some of the highlights that were accomplished during this effort are: (1) A forward-backward mass air flow sensor has been developed and a patent application for the device has been submitted. We are optimistic that this technology will have a particular application in variable valve timing direct injection systems for IC engines. (2) The biggest effort on this project has involved the development of the pneumatic-hydraulic valve actuation system. This system was originally purchased from Cargine, a Swedish supplier and is in the development stage. To date we have not been able to use the actuators to control the exhaust valves, although the actuators have been successfully employed to control the intake valves. The reason for this is the additional complication associated with variable back pressure on the exhaust valves when

  11. AIRE-Linux

    Science.gov (United States)

    Zhou, Jianfeng; Xu, Benda; Peng, Chuan; Yang, Yang; Huo, Zhuoxi

    2015-08-01

    AIRE-Linux is a dedicated Linux system for astronomers. Modern astronomy faces two big challenges: massive observed raw data which covers the whole electromagnetic spectrum, and overmuch professional data processing skill which exceeds personal or even a small team's abilities. AIRE-Linux, which is a specially designed Linux and will be distributed to users by Virtual Machine (VM) images in Open Virtualization Format (OVF), is to help astronomers confront the challenges. Most astronomical software packages, such as IRAF, MIDAS, CASA, Heasoft etc., will be integrated into AIRE-Linux. It is easy for astronomers to configure and customize the system and use what they just need. When incorporated into cloud computing platforms, AIRE-Linux will be able to handle data intensive and computing consuming tasks for astronomers. Currently, a Beta version of AIRE-Linux is ready for download and testing.

  12. Air/Water Purification

    Science.gov (United States)

    1992-01-01

    After 18 years of research into air/water pollution at Stennis Space Center, Dr. B. C. Wolverton formed his own company, Wolverton Environmental Services, Inc., to provide technology and consultation in air and water treatment. Common houseplants are used to absorb potentially harmful materials from bathrooms and kitchens. The plants are fertilized, air is purified, and wastewater is converted to clean water. More than 100 U.S. communities have adopted Wolverton's earlier water hyacinth and artificial marsh applications. Catfish farmers are currently evaluating the artificial marsh technology as a purification system.

  13. Transportation and air quality

    International Nuclear Information System (INIS)

    In the greater Vancouver regional district (GVRD), some 80% of the annual production of 600,000 tonnes of air pollutants come from motor vehicles. Three critical air quality issues in the GVRD are discussed: local air pollution, ozone layer depletion, and greenhouse gas emissions, all of which are fundamentally linked to transportation. Overall air quality in the GVRD has been judged acceptable by current federal standards, but ground-level ozone has exceeded maximum tolerable levels at some locations and concentrations of suspended particulates are above maximum acceptable levels. Serious deterioration in air quality has been predicted unless a concerted effort is made to manage air quality on an airshed-wide basis. The GVRD is developing Canada's first Air Management Plan with the goal of halving atmospheric emissions by 2000. GVRD transportation priorities stress public transit, walking, cycling, car pooling, and reducing of travel demand; however, the viability of such strategies depends on decisions made outside the transportation sector. Restricted authority and jurisdiction also hinder GVRD goals; the regional level of government has no authority over highways or transit and only has authority for pollution control in some parts of the Fraser Valley. Airshed quality management, using the Los Angeles example, is seen as a possible direction for future GVRD policymaking in the transportation sector. A single regional planning agency with responsibility for transportation, land use, and air quality management appears as the best option for an integrated approach to solve multiple problems. 19 refs

  14. Air Pollution

    OpenAIRE

    Lawther, P. J.

    2014-01-01

    The human costs of air pollution are considerable in Jordan. According to a report published in 2000 by the World Bank under the Mediterranean Environmental Technical Assistance Program (METAP), approximately 600 people die prematurely each year in Jordan because of urban pollution. 50-90% of air pollution in Jordanian towns is caused by road traffic. Readings taken in 2007 by Jordanian researchers showed that levels of black carbon particles in the air were higher in urban areas (caused by v...

  15. Qualidade do ar em ambientes internos hospitalares: estudo de caso e análise crítica dos padrões atuais Indoor air quality in hospitals: a case study and a critical review of current standards

    Directory of Open Access Journals (Sweden)

    Marina Eller Quadros

    2009-09-01

    Full Text Available O objetivo deste trabalho foi avaliar a qualidade do ar em três categorias de ambientes hospitalares: unidade de terapia intensiva (UTI adulto, UTI neonatal (UTN e centro cirúrgico de um hospital em Florianópolis, Brasil. Avaliaram-se a concentração de dióxido de carbono, a vazão e renovação de ar nas salas do centro cirúrgico. A concentração de bioaerossóis foi estimada em um dia de avaliação para cada ambiente. Não se observou relação entre a concentração de bioaerossóis e o tempo de uso das salas de cirurgia. A concentração média de bioaerossóis foi de 231 UFC.m-3 para fungos e de 187 UFC.m-3 para bactérias. Os ambientes avaliados atendiam aos valores recomendados pela legislação vigente. Os resultados permitiram avaliar criticamente essa legislação e apresentar sugestões para estabelecimento de uma resolução específica para ambientes hospitalares no Brasil.The objective of this paper was to evaluate the air quality in three indoor hospital environments: a neonatal intensive care unit (ICU, an adult ICU and a surgical ward of a hospital in Florianópolis, Brazil. Carbon dioxide concentrations, exchange air flow rates as well as fungi and bacteria concentrations were measured in these rooms. Bioaerosol concentrations were evaluated throughout one-work day for each operating room. No relationship was observed between bioaerosol concentration and the period of use in the surgical ward. Average bioaerosol concentrations were of 231 UFC.m-3 for filamentous fungi and 187 UFC.m-3 for bacteria. All environments evaluated were, overall, in compliance with current legislations. Results allowed a critical review of the present regulations and suggestions for the establishment of a specific regulation for hospital environments in Brazil.

  16. Counter-current flow limitation experiments in a model of the hot leg of a pressurised water reactor. Comparison between low pressure air/water experiments and high pressure steam/water experiments

    International Nuclear Information System (INIS)

    In order to investigate the two-phase flow behaviour in a complex reactor-typical geometry and to supply suitable data for CFD code validation, a model of the hot leg of a pressurized water reactor was built at Forschungszentrum Dresden-Rossendorf (FZD). The hot leg model is devoted to optical measurement techniques, therefore, a flat test section design was chosen and equipped with large windows. In order to enable the operation at high pressures, the test section is installed in the pressure chamber of the TOPFLOW test facility of FZD, which is used to perform the experiments under pressure equilibrium with the inside atmosphere. Counter-current flow limitation (CCFL) experiments were performed, simulating the reflux-condenser cooling mode appearing in small break LOCA scenarios. The fluids used were air and water at room temperature and pressures of up to 3.0 bar, as well as steam and water at pressures of up to 50 bar and the corresponding saturation temperature of 264degC. One selected 50 bar experiment is presented in detail: the observed behaviour is analysed and illustrated by typical high-speed camera images of the flow. Furthermore, the flooding characteristic obtained from the different experimental runs are presented in terms of the Wallis parameter and Kutateladze number, which are commonly used in the literature. However, both parameters fail to properly correlate the data: a discrepancy is observed between the air/water and steam/water series. Therefore, a modified Wallis parameter is proposed, which takes into account the effect of the fluid viscosities on the CCFL. The new parameter is validated against comparable data found in the literature, even though no data was found with such a large range of viscosities. This analysis points out that the effect of the dynamic viscosity on flooding has already been observed, but not identified. Furthermore, it is shown that the proposed modification of the Wallis parameter allows a significant improvement

  17. Air Force neutron dosimetry program

    International Nuclear Information System (INIS)

    Approximately 1000 Air Force personnel are monitored for neutron radiation resulting from various sources at more than thirty worldwide locations. Neutron radiation spanning several orders of magnitude in energy is encountered. The Air Force currently uses albedo thermoluminescent neutron dosimeters for personnel monitoring. The energy dependence of the albedo neutron dosimeter is a current problem and the development of site specific correction factors is ongoing. A summary of data on the energy dependence is presented as well as efforts to develop algorithms for the dosimeter. An overview of current Air Force neutron dosimetry users and needs is also presented

  18. Air Pollution.

    Science.gov (United States)

    Air quality is affected by many types of pollutants that are emitted from various sources, including stationary and mobile. These sources release both criteria and hazardous air pollutants, which cause health effects, ecological harm, and material damage. They are generally categ...

  19. Vehicles and Particulate Air Pollution

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The current scene relating to particles and vehicular emissions in UK is reviewed. The active research topics are health effects of particles, particle size and composition, modeling the fate of particles and assessing individual exposure. There is a National Air Quality Strategy combined with local air quality management which includes monitoring and assessment, dispersion modeling and development of management plans.

  20. Thin air

    OpenAIRE

    Jasanoff, Sheila

    2013-01-01

    Clearing the air How do we grasp the air? Without Michel Callon’s guidance, I might never have asked that question. Years ago, when I first entered environmental law practice, I took it for granted that problems such as air pollution exist “out there” in the real world for science to discover and law to fix. It is a measure of Callon’s influence that I understand the law today as a metaphysical instrument, no less powerful in its capacity to order nature than the tools of the ancient oracular...

  1. Air Pollution

    Science.gov (United States)

    ... to a close in June 2013 when the company, Conscious Clothing, was awarded the My Air grand ... Page Options: Request Translation Services Facebook Twitter LinkedIn Google+ Reddit Email Evernote More Increase Font Size Decrease ...

  2. Air ions and aerosol science

    Science.gov (United States)

    Tammet, Hannes

    1996-03-01

    Collaboration between Gas Discharge and Plasma Physics, Atmospheric Electricity, and Aerosol Science is a factor of success in the research of air ions. The concept of air ion as of any carrier of electrical current through the air is inherent to Atmospheric Electricity under which a considerable statistical information about the air ion mobility spectrum is collected. A new model of air ion size-mobility correlation has been developed proceeding from Aerosol Science and joining the methods of neighboring research fields. The predicted temperature variation of the mobility disagrees with the commonly used Langevin rule for the reduction of air ion mobilities to the standard conditions. Concurrent errors are too big to be neglected in applications. The critical diameter distinguishing cluster ions and charged aerosol particles has been estimated to be 1.4-1.8 nm.

  3. Air ions and aerosol science

    Energy Technology Data Exchange (ETDEWEB)

    Tammet, H. [Department of Environmental Physics, Tartu University, Tartu, Estonia (Estonia) 2400

    1996-03-01

    Collaboration between Gas Discharge and Plasma Physics, Atmospheric Electricity, and Aerosol Science is a factor of success in the research of air ions. The concept of air ion as of any carrier of electrical current through the air is inherent to Atmospheric Electricity under which a considerable statistical information about the air ion mobility spectrum is collected. A new model of air ion size-mobility correlation has been developed proceeding from Aerosol Science and joining the methods of neighboring research fields. The predicted temperature variation of the mobility disagrees with the commonly used Langevin rule for the reduction of air ion mobilities to the standard conditions. Concurrent errors are too big to be neglected in applications. The critical diameter distinguishing cluster ions and charged aerosol particles has been estimated to be 1.4{endash}1.8 nm. {copyright} {ital 1996 American Institute of Physics.}

  4. Air Cleaning Technologies

    Science.gov (United States)

    2005-01-01

    , and personal protection methods. Engineering methods that are usually carried out by the building’s heating, ventilation, and air conditioning (HVAC) system function to prevent the spread of airborne infectious pathogens by diluting (dilution ventilation) and removing (exhaust ventilation) contaminated air from a room, controlling the direction of airflow and the air flow patterns in a building. However, general wear and tear over time may compromise the HVAC system’s effectiveness to maintain adequate indoor air quality. Likewise, economic issues may curtail the completion of necessary renovations to increase its effectiveness. Therefore, when exposure to airborne infectious pathogens is a risk, the use of an in-room air cleaner to reduce the concentration of airborne pathogens and prevent the spread of airborne infectious diseases has been proposed as an alternative to renovating a HVAC system. Airborne transmission is the spread of infectious pathogens over large distances through the air. Infectious pathogens, which may include fungi, bacteria, and viruses, vary in size and can be dispersed into the air in drops of moisture after coughing or sneezing. Small drops of moisture carrying infectious pathogens are called droplet nuclei. Droplet nuclei are about 1 to 5μm in diameter. This small size in part allows them to remain suspended in the air for several hours and be carried by air currents over considerable distances. Large drops of moisture carrying infectious pathogens are called droplets. Droplets being larger than droplet nuclei, travel shorter distances (about 1 metre) before rapidly falling out of the air to the ground. Because droplet nuclei remain airborne for longer periods than do droplets, they are more amenable to engineering infection control methods than are droplets. Droplet nuclei are responsible for the airborne transmission of infectious diseases such as tuberculosis, chicken pox (varicella), measles (rubeola), and dessiminated herpes

  5. Indoor air pollution

    International Nuclear Information System (INIS)

    Indoor air pollution after being a neglected subject for a number of years, is attracting attention recently because it is a side effect of energy crisis. About 50% of world's 6 billion population, mostly in developing countries, depend on biomass and coal in the form of wood, dung and crop residues for domestic energy because of poverty. These materials are burnt in simple stoves with incomplete combustion and infants, children and women are exposed to high levels of indoor air pollution for a considerable period, approximately between 2-4 hours daily. Current worldwide trade in wood fuel is over US $7 billion and about 2 million people are employed full time in production and marketing it. One of the most annoying and common indoor pollutant in both, developing and developed countries, is cigarette smoke. Children in gas-equipped homes had higher incidences of respiratory disease. Babies' DNA can be damaged even before they are born if their mothers breathe polluted air. Exposure to indoor air pollution may be responsible for nearly 2 million excess deaths in developing countries and for 4% of the global burden of the disease. Only a few indoor pollutants have been studied in detail. Indoor air pollution is a major health threat on which further research is needed to define the extent of the problem more precisely and to determine solutions by the policy-makers instead of neglecting it because sufferers mostly belong to Third World countries. (author)

  6. Spin current

    CERN Document Server

    Valenzuela, Sergio O; Saitoh, Eiji; Kimura, Takashi

    2012-01-01

    In a new branch of physics and technology called spin-electronics or spintronics, the flow of electrical charge (usual current) as well as the flow of electron spin, the so-called 'spin current', are manipulated and controlled together. This book provides an introduction and guide to the new physics and application of spin current.

  7. PERFORMANCE OF AN AIR CLASSIFIER TO REMOVE LIGHT ORGANIC CONTAMINATION FROM ALUMINUM RECOVERED FROM MUNICIPAL WASTE BY EDDY CURRENT SEPARATION. TEST NO. 5.03, RECOVERY 1, NEW ORLEANS

    Science.gov (United States)

    The report describes a test in which aluminum cans recovered from municipal waste, together with known amounts of contaminant, were processed by a 'zig-zag' vertical air classifier to remove aerodynamically light contaminant. Twelve test runs were conducted; the proportions of co...

  8. Healthy Air Outdoors

    Science.gov (United States)

    ... lung.org > Our Initiatives > Healthy Air > Outdoor Healthy Air Outdoors The quality of the air we breathe ... families and can even shorten their lives. Outdoor Air Pollution and Health Outdoor air pollution continues to ...

  9. Air quality

    International Nuclear Information System (INIS)

    This chapter of the 'Assessment of the state of the environment in Lebanon' describes the air quality and identifies the most important air quality issues. Baseline information about the factors affecting dispersion and the climate of Lebanon presents as well and overall estimation of total emissions in Lebanon. Emissions from vehicles, electricity and power plants generation are described. Industrial emitters of air pollutants are described for each kind of industry i.e.cement plants, Selaata fertilizer factory, sugar-beet factory, refineries and for those derived from the use of leaded fuel . Impact of economic and human activities on air quality in Lebanon (especially in Beirut and Tripoli) are quantified by quantities of CO2, SO2, NOx, total suspended particulates(TSP), deposition and their environmental effects on health. In abscence of emissions monitoring, data available are expressed in terms of fuel use, output and appropriate empirical factors, national output and workfores sizes. Finally key issues and some potential mitigation /management approaches are presented

  10. Royal Danish Air Force. Air Operations Doctrine

    DEFF Research Database (Denmark)

    Nørby, Søren

    This brief examines the development of the first Danish Air Force Air Operations Doctrine, which was officially commissioned in October 1997 and remained in effect until 2010. The development of a Danish air power doctrine was heavily influenced by the work of Colonel John Warden (USAF), both...... through his book ”The Air Campaign” and his subsequent planning of the air campaign against Iraq in 1990-1991. Warden’s ideas came to Denmark and the Danish Air Force by way of Danish Air Force students attending the United States Air Force Air University in Alabama, USA. Back in Denmark, graduates from...... the Air University inspired a small number of passionate airmen, who then wrote the Danish Air Operations Doctrine. The process was supported by the Air Force Tactical Command, which found that the work dovetailed perfectly with the transformation process that the Danish Air Force was in the midst of...

  11. Managing Air in Olympic Cities

    Directory of Open Access Journals (Sweden)

    Qing W. Tian

    2008-01-01

    Full Text Available The 21st century Olympic Agenda aims to align itself with the concept of sustainable development and has driven improved environmental quality in host cities, such as the Green Games in Sydney 2000 and the planned Beijing 2008 Games and in London 2012 as the Low Carbon Games. Air quality has long been a concern of Olympic mega-cities, although the air quality plans and strategies have often seemed short-lived and unsustainable in the long term. We have explored air quality data and air pollution control from seven Olympic cities: Mexico City, Los Angeles, Atlanta, Sydney and Athens and also Beijing and London which will host Olympic Games in near future. The study shows that despite a high altitude and air pollution problems, Mexico City had no clear environmental policy in place for the 1968 games. The characteristic smog of Los Angeles raised concerns about athletic performance at the Olympic Games of 1984, but there were limited efforts to tackle the ozone concentration during these games. The 1996 Atlanta Games represents a case where temporary public transport changes were used as a tactic to reduce air pollution. In Sydney a well planned sustainable strategy reduced air pollutants and CO2 emissions in 2000, but Athens' long efforts to improve air quality for the 2004 games were not wholly effective. Even where strategies proved successful the improvements in air quality seem short-lived. Current host cities Beijing and London are developing emission reduction plans. These have clear air quality objectives and are well intentioned. However, the improvements may be too narrow and may not be sustainable in the long term. Our analysis looks at the origins of success and failure and how more coherent improvements might be achieved and what would promote sustainable plans for air quality management at future games. The study illustrates the feedback between air pollution science and policy awareness.

  12. Current stabilizer

    International Nuclear Information System (INIS)

    A current stabilizer for supplying magnetic lens of β-monochromator at the electron energy up to 1 MeV is described. Stabilization method with use of reference high-stabilized source of direct voltage with switching-in loading (monochromator coil) to circuit of negative feedback of direct-current amplifier with high gain is chosen for stabilization of direct current. The range of current regulation is 0.5 A at available power up to 15 W. Current instability during 10 hour continuous work does not exceed 10-4% that makes it possible to provide instability of electron energy at the monochromator exit using 90Sr+90Y β-nucleide of not more than 10 -4% and number of electrons 2.5x10-4% respectively

  13. Molecular Epidemiology and Air Pollution

    Czech Academy of Sciences Publication Activity Database

    Rössner ml., Pavel; Binková, B.; Rössnerová, Andrea; Šrám, Radim

    Rieka: InTech, 2015 - (Nejadkoorki, F.), s. 609-643 ISBN 978-953-51-2180-0 R&D Projects: GA ČR GA13-13458S Institutional support: RVO:68378041 Keywords : molecular epidemiology * biomarkers * human populations * in vitro studies Subject RIV: DN - Health Impact of the Environment Quality http://www.intechopen.com/books/current-air-quality-issues/molecular-epidemiology-and-air- pollution

  14. The lithium air battery fundamentals

    CERN Document Server

    Imanishi, Nobuyuki; Bruce, Peter G

    2014-01-01

    Lithium air rechargeable batteries are the best candidate for a power source for electric vehicles, because of their high specific energy density. In this book, the history, scientific background, status and prospects of the lithium air system are introduced by specialists in the field. This book will contain the basics, current statuses, and prospects for new technologies. This book is ideal for those interested in electrochemistry, energy storage, and materials science.

  15. Air filtration and indoor air quality

    DEFF Research Database (Denmark)

    Bekö, Gabriel

    2006-01-01

    Demands for better indoor air quality are increasing, since we spend most of our time indoors and we are more and more aware of indoor air pollution. Field studies in different parts of the world have documented that high percentage of occupants in many offices and buildings find the indoor air...... decent ventilation and air cleaning/air filtration, high indoor air quality cannot be accomplished. The need for effective air filtration has increased with increasing evidence on the hazardous effects of fine particles. Moreover, the air contains gaseous pollutants, removal of which requires various air...... cleaning techniques. Supply air filter is one of the key components in the ventilation system. Studies have shown that used ventilation filters themselves can be a significant source of indoor air pollution with consequent impact on perceived air quality, sick building syndrome symptoms and performance...

  16. Norma Primaria de calidad del aire AIR QUALITY STANDARD

    Directory of Open Access Journals (Sweden)

    PATRICIA MATUS C.

    2002-04-01

    Full Text Available Las normas primarias de calidad del aire tienen por finalidad proteger la salud de la población de la contaminación atmosférica. Ellas establecen un nivel de riesgo socialmente aceptado. Este artículo describe los antecedentes considerados durante el proceso de actualización de la regulación vigente en Chile. Detalla conceptos sobre la calidad del aire, describe los efectos en la salud de los contaminantes, y el procedimiento seguido para fijar los nuevos estándares Finaliza enumerando la norma primaria de calidad del aire, sus valores y los limites definidos para ser considerados en el ámbito de la gestión de los episodios críticos o de alta contaminaciónThe main purpose of air quality standards is to protect people health from air pollution. They establish a socially accepted level of risk. This article describes the background information considered during the process for updating the current Chilean regulation. Concepts about quality of air, and the effects of the pollutants on the health are described. The procedure followed to fix the new standards is detailed. Finally we state the primary air quality norm, its values as well as the critical limits in order to control critical events of high air pollution

  17. Free Flight vs. Centralized Air Traffic Management

    OpenAIRE

    Octavian Thor PLETER; Bogdan DONCIU

    2011-01-01

    The current Air Traffic Management system is subject to structural changes, which are expected over the next 20 years.These changes are required for a number of reasons:The current system inflicts delays and fuel inefficiencies to flights (as demonstrated by the historic Paris-Miami Air France flight in April 2010)The current system has structural and operational capacity limitationsUnder current system, the complexity of the Air Traffic Controller’s work increases steeply with trafficVoi...

  18. Air System Information Management

    Science.gov (United States)

    Filman, Robert E.

    2004-01-01

    I flew to Washington last week, a trip rich in distributed information management. Buying tickets, at the gate, in flight, landing and at the baggage claim, myriad messages about my reservation, the weather, our flight plans, gates, bags and so forth flew among a variety of travel agency, airline and Federal Aviation Administration (FAA) computers and personnel. By and large, each kind of information ran on a particular application, often specialized to own data formats and communications network. I went to Washington to attend an FAA meeting on System-Wide Information Management (SWIM) for the National Airspace System (NAS) (http://www.nasarchitecture.faa.gov/Tutorials/NAS101.cfm). NAS (and its information infrastructure, SWIM) is an attempt to bring greater regularity, efficiency and uniformity to the collection of stovepipe applications now used to manage air traffic. Current systems hold information about flight plans, flight trajectories, weather, air turbulence, current and forecast weather, radar summaries, hazardous condition warnings, airport and airspace capacity constraints, temporary flight restrictions, and so forth. Information moving among these stovepipe systems is usually mediated by people (for example, air traffic controllers) or single-purpose applications. People, whose intelligence is critical for difficult tasks and unusual circumstances, are not as efficient as computers for tasks that can be automated. Better information sharing can lead to higher system capacity, more efficient utilization and safer operations. Better information sharing through greater automation is possible though not necessarily easy.

  19. 78 FR 30829 - Approval and Promulgation of Air Quality Implementation Plans; Illinois; Air Quality Standards...

    Science.gov (United States)

    2013-05-23

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Illinois; Air Quality Standards Revision AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule. SUMMARY... current national ambient air quality standards (NAAQS) for ozone, lead, and particulate matter. EPA...

  20. Air Filtration as Protection against Fouling of Ventilation and Air Conditioning Units

    DEFF Research Database (Denmark)

    Bekö, Gabriel; Lajčíková, Ariana

    2005-01-01

    Currently, air filters are one of the most critical components of air treatment systems as they decontaminate the air delivered to living space. During the operation, however, the level of harmful surface deposits increases, and at certain times, an uncleaned filter can itself become a source of ...

  1. R9 Air Districts

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Region 9 Air Districts layer is a compilation of polygons representing the California Air Pollution Control and Air Quality Management Districts, Arizona Air...

  2. AirData

    Data.gov (United States)

    U.S. Environmental Protection Agency — The AirData site provides access to yearly summaries of United States air pollution data, taken from EPA's air pollution databases. AirData has information about...

  3. California Air Basins

    Data.gov (United States)

    California Department of Resources — Air ResourcesCalifornia Air Resources BoardThe following datasets are from the California Air Resources Board: * arb_california_airbasins - California Air BasinsThe...

  4. Hazardous Air Pollutants

    Science.gov (United States)

    ... Facebook Twitter Google+ Pinterest Contact Us Hazardous Air Pollutants Hazardous air pollutants are those known to cause ... protect against adverse environmental effects. About Hazardous Air Pollutants What are hazardous air pollutants? Health and Environmental ...

  5. Neutral currents

    International Nuclear Information System (INIS)

    The evidence for the existence of weak neutral current has been a very controverted topics in the early 1970's, as well as the muon did in the 1930's. The history is very rich considering the evolution of the experimental techniques in high energy particle physics. The history of the discovery and the study of weak neutral current is reviewed. Later the quest of the intermediate vector boson continues with the decision of the community to build a large proton antiproton collider. (K.A.). 14 refs., 1 fig

  6. Air quality in Europe - 2011 report

    Energy Technology Data Exchange (ETDEWEB)

    Guerreiro, C.; Larssen, S. (Norsk Inst. for Luftforskning (NILU), Lillestroem (Norway)); Leeuw, F. de (RIVM, Bilthoven (Netherlands)); Foltescu, V. (EEA, Copenhagen (Denmark))

    2011-11-15

    The annual report 'Air quality in Europe' summarises the most recent evaluation of Europe's air quality status. It is mainly based on air quality measurement data that have been made available officially by 32 EEA member countries as well as 6 EEA cooperating countries. The report includes maps and analyses of air quality status over the calendar year 2009. It also analyses air quality trends over the past years. The evaluation of the status and trends of air quality is based on ambient air measurements, in conjunction with reported anthropogenic emissions. The report summarizes the main effects of different air pollutants on human health, the environment and the climate. An overview of policies and measures at European level is also given for each pollutant. This report reviews progress towards meeting the requirements of the two air quality directives in force as well as the air quality guidelines set by the World Health Organization (WHO). The report is produced in support of European and national policy development and implementation in the field of air quality. It also supports air quality management and informs the general public on the current status and trends of air quality in Europe. (Author)

  7. Current Titles

    Energy Technology Data Exchange (ETDEWEB)

    Various

    2006-06-01

    This booklet is published for those interested in current research being conducted at the National Center for Electron Microscopy. The NCEM is a DOE-designated national user facility and is available at no charge to qualified researchers. Access is controlled by an external steering committee. Interested researchers may contact Jane Cavlina, Administrator, at 510/486-6036.

  8. Control of air toxics

    International Nuclear Information System (INIS)

    For more than 10 years, Argonne National Laboratory has supported the US DOE's Flue Gas Cleanup Program objective by developing new or improved environmental controls for industries that use fossil fuels. Argonne's pollutant emissions research has ranged from experiments in the basic chemistry of pollution-control systems, through laboratory-scale process development and testing, to pilot-scale field tests of several technologies. The work on air toxics is currently divided into two components: Investigating measures to improve the removal of mercury in existing pollution-control systems applied to coal combustion; and, Developing sensors and control techniques for emissions found in the textile industry

  9. Pressurized air supply device

    International Nuclear Information System (INIS)

    Ventilation air-conditioning facilities in a nuclear reactor building are adapted to suck clean external air not containing radioactivity through air supply filters disposed at an air intake port of the nuclear reactor building by means of an air supply blower and then supply the sucked air through an air supply duct and an air supply port to the inside of the power plant. Futher, pipeways for supplying sucked air to a compressor is branched from the air supply duct, through which air is supplied to an air compressor for instrumentation and an air compressor used in the power plant. The air sucked and compressed in the air compressor for instrumentation is further supplied by way of pipeways for supplying air for instrumentation to air-actuated valves, instruments, etc. Further, air sucked and compressed in the air compressor used in the power plant is further supplied by way of air supply pipeways for the power plant to a reservoir, air mask, etc. By supplying clean compressed air in this way, operators exposure dose can be reduced. (T.M.)

  10. In Brief: Air pollution app

    Science.gov (United States)

    Showstack, Randy

    2010-10-01

    A new smartphone application takes advantage of various technological capabilities and sensors to help users monitor air quality. Tapping into smartphone cameras, Global Positioning System (GPS) sensors, compasses, and accelerometers, computer scientists with the University of Southern California's (USC) Viterbi School of Engineering have developed a new application, provisionally entitled “Visibility.” Currently available for the Android telephone operating system, the application is available for free download at http://robotics.usc.edu/˜mobilesensing/Projects/AirVisibilityMonitoring. An iPhone application may be introduced soon. Smartphone users can take a picture of the sky and then compare it with models of sky luminance to estimate visibility. While conventional air pollution monitors are costly and thinly deployed in some areas, the smartphone application potentially could help fill in some blanks in existing air pollution maps, according to USC computer science professor Gaurav Sukhatme.

  11. Neutral Current $\

    CERN Document Server

    Chauhan, S; Singh, S K

    2011-01-01

    We calculate cross sections for the neutral current induced neutrino/antineutrino reaction from $^{208}Pb$ target and applied it to study Supernova neutrino event rates. The calculations are done in local density approximation taking into account Pauli blocking, Fermi motion effects and renormalization of weak transition strengths in the nuclear medium. The numerical results for the neutrino nucleus total cross sections have been averaged over the various Supernova neutrino/antineutrino fluxes available in literature.

  12. Air movement and perceived air quality

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Kaczmarczyk, J.

    2012-01-01

    The impact of air movement on perceived air quality (PAQ) and sick building syndrome (SBS) symptoms was studied. In total, 124 human subjects participated in four series of experiments performed in climate chambers at different combinations of room air temperature (20, 23, 26 and 28 °C), relative...... humidity (30, 40 and 70%) and pollution level (low and high). Most of the experiments were performed with and without facially applied airflow at elevated velocity. The importance of the use of recirculated room air and clean, cool and dry outdoor air was studied. The exposures ranged from 60. min to 235....... min. Acceptability of PAQ and freshness of the air improved when air movement was applied. The elevated air movement diminished the negative impact of increased air temperature, relative humidity and pollution level on PAQ. The degree of improvement depended on the pollution level, the temperature and...

  13. Clean Air Act. Revision 5

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-15

    This Reference Book contains a current copy of the Clean Air Act, as amended, and those regulations that implement the statute and appear to be most relevant to DOE activities. The document is provided to DOE and contractor staff for informational purposes only and should not be interpreted as legal guidance. This Reference Book has been completely revised and is current through February 15, 1994.

  14. Air filtration and indoor air quality

    DEFF Research Database (Denmark)

    Bekö, Gabriel

    decent ventilation and air cleaning/air filtration, high indoor air quality cannot be accomplished. The need for effective air filtration has increased with increasing evidence on the hazardous effects of fine particles. Moreover, the air contains gaseous pollutants, removal of which requires various air...... contradictions should motivate manufacturers and researchers to develop new efficient filtration techniques and/or improve the existing ones. Development of low polluting filtration techniques, which are at the same time easy and inexpensive to maintain is the way forward in the future....

  15. European Private Law: Up in the Air?

    OpenAIRE

    Luzak, J.; Bobek, M.; Prassl, J.

    2016-01-01

    This paper compares the existing rights granted to consumers when they purchase services in the EU, whether in a shop or within a distance selling scheme, with the provisions of Regulation 261/2004. While the works on the new European rules on air passengers’ rights are still ongoing it is important to examine what protection measures the air passengers are currently missing that European consumers may already be enjoying while concluding contracts other than for air transport services. Addit...

  16. Air pollution: UNCED convention on climate change

    International Nuclear Information System (INIS)

    In addition to United Nations papers delineating the Organization's convention on climate change and strategies concerning the protection of the earth's atmosphere, this booklet presents four papers expressing the views of Italian and American strategists. The central theme is the establishment of current global air pollution trends, the determination of suitable air pollution limits, and the preparation of feasible socio-economic strategies to allow industrialized and developing countries to work together effectively to achieve the proposed global air quality goals

  17. Current titles

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    This booklet is published for those interested in current research being conducted at the National Center for Electron Microscopy. The NCEM is a DOE-designated national user facility and is available at no charge to qualified researchers. Access is controlled by an external steering committee. Interested researchers may contact Gretchen Hermes at (510) 486-5006 or address below for a User`s Guide. Copies of available papers can be ordered from: Theda Crawford National Center for Electron Microscopy, Lawrence Berkeley Laboratory, One Cyclotron Rd., MS72, Berkeley, California, USA 94720.

  18. Current ornithology

    CERN Document Server

    1983-01-01

    The appearance of the first volume of a projected series is the occasion for comment on scope, aims, and genesis of the work. The scope of Current Ornithology is all of the biology of birds. Ornithology, as a whole-organism science, is concerned with birds at every level of bi­ ological organization, from the molecular to the community, at least from the Jurassic to the present time, and over every scholarly discipline in which bird biology is done; to say this is merely to expand a dic­ tionary definition of "ornithology. " The aim of the work, to be realized over several volumes, is to present reviews or position statements con­ cerning the active fields of ornithological research. The reviews will be relatively short, and often will be done from the viewpoint of a readily­ identified group or school. Such a work could have come into being at any time within the past fifty years, but that Current Ornithology appears now is a result of events that are only seven to eight years old. One important event wa...

  19. Estimating the Mean Annual Surface Air Temperature at Armagh Observatory, Northern Ireland, and the Global Land-Ocean Temperature Index for Sunspot Cycle 24, the Current Ongoing Sunspot Cycle

    Science.gov (United States)

    Wilson, Robert M.

    2013-01-01

    surface air temperature (ASAT) and the Global Land-Ocean Temperature Index (GLOTI) in relation to SSN and the SC in order to determine their likely values during SC24. Hence, it may provide insight as to whether solar forcing of global temperature is now lessening as a contributor to global warming, thereby indicating a possible cooling in the near term immediate future that potentially could ameliorate the effect of increased anthropogenic warming.

  20. Megacities, air quality and climate

    Science.gov (United States)

    Baklanov, Alexander; Molina, Luisa T.; Gauss, Michael

    2016-02-01

    The rapid urbanization and growing number of megacities and urban complexes requires new types of research and services that make best use of science and available technology. With an increasing number of humans now living in urban sprawls, there are urgent needs of examining what the rising number of megacities means for air pollution, local climate and the effects these changes have on global climate. Such integrated studies and services should assist cities in facing hazards such as storm surge, flooding, heat waves, and air pollution episodes, especially in changing climates. While important advances have been made, new interdisciplinary research studies are needed to increase our understanding of the interactions between emissions, air quality, and regional and global climates. Studies need to address both basic and applied research and bridge the spatial and temporal scales connecting local emissions and air pollution and local weather, global atmospheric chemistry and climate. This paper reviews the current status of studies of the complex interactions between climate, air quality and megacities, and identifies the main gaps in our current knowledge as well as further research needs in this important field of research.

  1. Air protection. Ochrana ovzdusia

    Energy Technology Data Exchange (ETDEWEB)

    Siska, F.

    1980-01-01

    This paper discusses problems of air pollution control, air pollution abatement and effects of air pollution. Air pollution caused by black and brown coal combustion, by fossil-fuel power plants and by coking plants is evaluated. Air pollution by dusts, sulfur oxides, nitrogen oxides, carbon monoxide, ammonia as well arsenic, barium, beryllium, boron, chromium, gallium, cobalt, manganese, copper, nickel, lead, plutonium, titanium and vanadium, which sometimes accompany ashes in coal, is analyzed. Methods of air pollution abatement such as fluidized bed combustion, coal preparation, desulfurization or dry coke quenching are described. Systems for air pollution control are presented: air filtration, cyclones, electrostatic precipitators. Systems of air pollution measurement and recording are evaluated. Propagation of air pollutants in the atmosphere as well as the factors which influence pollutant propagation are characterized. Problems associated with site selection for fossil-fuel power plants are also discussed. An analysis of economic aspects of air pollution abatement and air pollution control is made. (55 refs.)

  2. Indoor Air Quality

    Science.gov (United States)

    ... protect yourself and your family. Learn more Air Quality at Work Workers should breathe easy while on the job, but worksites with poor air quality put employees at risk. Healthy air is essential ...

  3. HEPA air filter (image)

    Science.gov (United States)

    ... pet dander and other irritating allergens from the air. Along with other methods to reduce allergens, such ... controlling the amount of allergens circulating in the air. HEPA filters can be found in most air ...

  4. Bad Air Day

    Science.gov (United States)

    ... link, please review our exit disclaimer . Subscribe Bad Air Day Air Quality and Your Health In many parts of the country, summer has the worst air quality of any season. When the forecast says ...

  5. Air quality indices : a review

    International Nuclear Information System (INIS)

    Pollution Probe presents some background information that will help in the development of a national Air Quality Index (AQI) in Canada. This report examines the issues that should be addressed in revising the national Index of the Quality of Air (IQUA) or creating a new national Air Quality Index. The IQUA was devised in 1976 and provides Canadians with real-time information on the state of community air quality by including major pollutants and their synergies. It is currently being used for air quality management plans and air quality alert systems. At the same time that the IQUA was devised, the United States Environmental Protection Agency (US EPA) produced a parallel air quality index known as the Pollution Standard Index (PSI) which incorporated 5 criteria pollutants (particulate matter, sulphur dioxide, carbon monoxide, nitrogen oxide and ground level ozone) for which national health-based standards were devised. In 1999, the US EPA renamed their index the Air Quality Index (AQI) and made revisions to the primary health-based national ambient air quality standards for ground-level ozone and particulate matter. Separate values for PM2.5 and PM10 were incorporated and mandatory reporting was required for metropolitan areas with populations of 350,000 or more. Similarly, the IQUA has undergone major developments that affect the validity of the index, including: rejection by the Working Group on Air Quality Objectives and Guidelines of the previous maximum desirable and maximum acceptable air quality criteria, recognition that standards for many of the contaminants are outdated, developing more sensitive instrumentation for real-time monitoring of contaminants. This report also describes the use of the national short term Air Quality Index by provincial, territorial and local authorities in Canada. Pollution Probe recommends setting up a mechanism to review and revise IQUA on a regular basis that would incorporate governments, the medical profession, special

  6. Isothermal air ingress validation experiments

    International Nuclear Information System (INIS)

    Idaho National Laboratory carried out air ingress experiments as part of validating computational fluid dynamics (CFD) calculations. An isothermal test loop was designed and set to understand the stratified-flow phenomenon, which is important as the initial air flow into the lower plenum of the very high temperature gas cooled reactor (VHTR) when a large break loss-of-coolant accident occurs. The unique flow characteristics were focused on the VHTR air-ingress accident, in particular, the flow visualization of the stratified flow in the inlet pipe to the vessel lower plenum of the General Atomic's Gas Turbine-Modular Helium Reactor (GT-MHR). Brine and sucrose were used as heavy fluids, and water was used to represent a light fluid, which mimics a counter current flow due to the density difference between the stimulant fluids. The density ratios were changed between 0.87 and 0.98. This experiment clearly showed that a stratified flow between simulant fluids was established even for very small density differences. The CFD calculations were compared with experimental data. A grid sensitivity study on CFD models was also performed using the Richardson extrapolation and the grid convergence index method for the numerical accuracy of CFD calculations . As a result, the calculated current speed showed very good agreement with the experimental data, indicating that the current CFD methods are suitable for predicting density gradient stratified flow phenomena in the air-ingress accident. (author)

  7. ISOTHERMAL AIR INGRESS VALIDATION EXPERIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Chang H Oh; Eung S Kim

    2011-09-01

    Idaho National Laboratory carried out air ingress experiments as part of validating computational fluid dynamics (CFD) calculations. An isothermal test loop was designed and set to understand the stratified-flow phenomenon, which is important as the initial air flow into the lower plenum of the very high temperature gas cooled reactor (VHTR) when a large break loss-of-coolant accident occurs. The unique flow characteristics were focused on the VHTR air-ingress accident, in particular, the flow visualization of the stratified flow in the inlet pipe to the vessel lower plenum of the General Atomic’s Gas Turbine-Modular Helium Reactor (GT-MHR). Brine and sucrose were used as heavy fluids, and water was used to represent a light fluid, which mimics a counter current flow due to the density difference between the stimulant fluids. The density ratios were changed between 0.87 and 0.98. This experiment clearly showed that a stratified flow between simulant fluids was established even for very small density differences. The CFD calculations were compared with experimental data. A grid sensitivity study on CFD models was also performed using the Richardson extrapolation and the grid convergence index method for the numerical accuracy of CFD calculations . As a result, the calculated current speed showed very good agreement with the experimental data, indicating that the current CFD methods are suitable for predicting density gradient stratified flow phenomena in the air-ingress accident.

  8. Neutral currents

    International Nuclear Information System (INIS)

    A short survey of the new experimental data on weak neutral currents is given, followed by a comparison with modern theoretical models. Cross sections of the anti νsub(e)e → anti νsub(e)e, anti νsub(μ)e→ νsub(μ)e, νp → νp and anti νp → anti νp elastic scattering as well as inclusive cross sections of the ν+N → ν+X and anti ν+N → anti ν+X deep inelastic scattering are presented. On the basis of the comparison the Weinberg-Salam model is concluded to be in a good agreement with the shape of the cross sections. Six-quark vector models appear to be ruled out. The five-quark model due to Achiman, Koller and Walsh and two versions of the Gursey-Sikivie model satisfactorily account for the observed data in shape and in magnitude

  9. ATMOSPHERIC AIR QUALITY IN CALARASI TOWN

    OpenAIRE

    Cecilia NEAGU

    2013-01-01

    The present paper seeks to highlight the appearance of air pollution in Calarasi region on the basis of the annual reports of the environment in recent years and of the integrated air quality management for Cǎlǎraşi (data are presented about current and future emissions and concentrations of pollutants) I tried to mark out the impurity of the atmospheric air from this area.Emission data interpretation was made on the basis of the inventory of emissions of pollutants in the air made for fixed ...

  10. LHC data and extensive air showers

    Directory of Open Access Journals (Sweden)

    Pierog Tanguy

    2013-06-01

    Full Text Available Currently the uncertainty in the prediction of shower observables for different primary particles and energies is dominated by differences between hadronic interaction models. The LHC data on minimum bias measurements can be used to test Monte Carlo generators and these new constraints will help to reduce the uncertainties in air shower predictions. In this article, after a short introduction on air showers we will show the results of the comparison between the updated version of high energy hadronic interaction models EPOS LHC and QGSJETII-04 with LHC data. Results for air shower simulations and their consequences on comparisons with air shower data will be discussed.

  11. LHC data and extensive air showers

    International Nuclear Information System (INIS)

    Currently the uncertainty in the prediction of shower observables for different primary particles and energies is dominated by differences between hadronic interaction models. The LHC data on minimum bias measurements can be used to test Monte Carlo generators and these new constraints will help to reduce the uncertainties in air shower predictions. In this article, after a short introduction on air showers we will show the results of the comparison between the updated version of high energy hadronic interaction models EPOS LHC and QGSJETII-04 with LHC data. Results for air shower simulations and their consequences on comparisons with air shower data will be discussed. (authors)

  12. Air pollution dispersion models as used in Poland in regional development planning

    Energy Technology Data Exchange (ETDEWEB)

    Pruchnicki, J.

    1977-02-01

    This paper discusses air pollution models used in regional development planning in Poland. After outlining the institutional structure and legislature dealing with air pollution control, the paper describes the air quality standards currently in effect. Dispersion models used in predicting air pollution concentrations are then detailed. Finally the application of air pollution modelling to urban design is discussed.

  13. Air quality and urban management in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Alberti, M. [Stanford Univ. (United States). Center for Conservation Biology; Joffre, S. [Finnish Meteorological Inst., Helsinki (Finland)

    1995-12-31

    Important changes in the quality of urban air have occurred in Europe during the last 20 years. Urban air quality trends are clearly correlated to changes in production and consumption processes which have occurred in European cities during the last decades. However, the way these trends are linked with the changes in the urban structure is not yet fully appreciated. A set of indicators is proposed to examine the relationships between air quality, energy consumption and transportation trends. On this basis is argued that the current decentralization of the urban structure and specialization of land use are major driving forces in current urban air pollution. The range of actions and tools to improve urban air quality should include: (1) land use planning, (2) efficient urban management, and (3) measures directed to protecting the quality of the urban environment. (author)

  14. Metal-air electrochemical cell

    Energy Technology Data Exchange (ETDEWEB)

    Sarbacher, R. I.; Fechter, H. R.

    1985-01-01

    An electrochemical cell for which fuel is prepared and introduced under artificial gravity forces. The active metal is deposited through the action of the field on an anode current collecting member, effecting good compaction and reduced cell internal impedance. A microprocessor provides control of the induced gravity, flow rates, temperature, and other variables-enabling the active metal to be controlled in its thickness as well as providing a predetermined separation from the cathode. Abrasion of the cathode and the possibility of shorting are avoided by the presence of outwardly directed radial forces. These forces are induced by rotation of the electrolyte, air cathode, anode collector and the active metal. The forces promote also the passage of moisture laden air through the air cathode elements. Reaction products produced within the cell volume are circulated to an outside container for separation and possible reuse.

  15. Urban air quality management. V. 1

    International Nuclear Information System (INIS)

    This is the first in a series of reports commissioned by the International Petroleum Industry Environmental Conservation Association (IPIECA) to represent members' views on the management of urban air quality in the growing cities in developing countries. In this report, a general, science based framework is provided as a basis for understanding the nature of the problem in any specific urban area, the range of solutions that might be available, and the potential impact of each solution and its least cost privatisation. The topics covered are: a process for urban air quality management; setting air quality targets; a structured approach to the assessment of current and future air quality modelling methodologies; identification and collation of air quality model input data; development of socio-economic scenarios -long-term trend forecasting; cost effectiveness studies; the IPIECA approach to urban air quality management - development of partnerships; encouraging commitment to implementation of programme recommendations. (7 figures; 2 tables; 18 references). (UK)

  16. REACH. Air Conditioning Units.

    Science.gov (United States)

    Garrison, Joe; And Others

    As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of air conditioning. The instructional units focus on air conditioning fundamentals, window air conditioning, system and installation, troubleshooting and…

  17. The weight of air

    International Nuclear Information System (INIS)

    Once a controversial idea, the fact that gases like air have weight can easily be demonstrated using reasonably precise scales in the modern teaching laboratory. But unlike a liquid, where a mechanical model suggests a pile of hard spheres resting on each other, gas molecules are in continual motion and can have minimal interaction. How should we think about the effect these molecules have on the scale? And more importantly, how should we explain it to students? Several models of gas behavior are employed to answer these questions and it is shown how the weight of a gas is, like electric current, an emergent phenomena in contrast to the weight of a liquid which is direct or causal. (paper)

  18. Indoor Air Pollution (Environmental Health Student Portal)

    Science.gov (United States)

    ... Students to Environmental Health Information Menu Home Air Pollution Air Pollution Home Indoor Air Pollution Outdoor Air Pollution ... Pollution Indoor Air Pollution Print this Page Air Pollution Air Pollution Home Indoor Air Pollution Outdoor Air Pollution ...

  19. Air transport of plutonium metal: content expansion initiative for the plutonium air transportable (PAT01) packaging

    Energy Technology Data Exchange (ETDEWEB)

    Caviness, Michael L [Los Alamos National Laboratory; Mann, Paul T [NNSA/ALBUQUERQUE; Yoshimura, Richard H [SNL

    2010-01-01

    The National Nuclear Security Administration (NNSA) has submitted an application to the Nuclear Regulatory Commission (NRC) for the air shipment of plutonium metal within the Plutonium Air Transportable (PAT-1) packaging. The PAT-1 packaging is currently authorized for the air transport of plutonium oxide in solid form only. The INMM presentation will provide a limited overview of the scope of the plutonium metal initiative and provide a status of the NNSA application to the NRC.

  20. Investigating the air quality in aircraft cabins

    International Nuclear Information System (INIS)

    In recent years, there has been increasing concern about the air quality in aircraft cabins and its effects on health and safety for crew and passengers. Some of the major worries are risk of communication of infectious diseases, high incidence of respiratory diseases caused by low air moisture, and increased concentration of carbon dioxide from exhaled air due to the cabin air being recirculated. It also happens that fumes and gases enter the cabin by way of the ventilation system. This article describes the EU-funded research programme called CabinAir. The project aims to: (1) establish the current level of air quality in aircraft cabins, (2) establish the relationship between cabin air quality and the performance of environmental control and filtration systems, the air distribution, the energy consumption and the environmental impact of fuel burn. (3) develop new designs and technical solutions to improve the environmental control system and cabin air distribution/control systems, (4) optimise air quality in the cabin and minimise fuel consumption and environmental impacts, (5) develop performance specifications for the components, (6) draft European Pre-Normative Standards

  1. Technology Candidates for Air-to-Air and Air-to-Ground Data Exchange

    Science.gov (United States)

    Haynes, Brian D.

    2015-01-01

    underlying architecture of ground-air and air-air communications as a whole, rather than as simple "link to function" paired solutions. For the business case analysis, a number of "reference architectures" were developed for both the future technologies and the current systems, based on three typical configurations of current aircraft. Current and future costs were assigned, and various comparisons made between the current and future architectures. In general, it was assumed that if a future architecture offers lower cost than the current typical architecture, while delivering equivalent or better performance, it is likely that the future solution will gain industry acceptance. Conversely, future architectures presenting higher costs than their current counterparts must present a compelling benefit case in other areas or risk a lack of industry acceptance. The business case analysis consistently indicated lower costs for the proposed future architectures, and in most cases, significantly so. The proposed future solutions were found to offer significantly greater functionality, flexibility, and growth potential over time, at lower cost, than current systems. This was true for overall, fleet-wide equipage for domestic and oceanic air carriers, as well as for single, General Aviation (GA) aircraft. The overall research results indicate that all identified requirements can be met by the proposed solutions with significant capacity for future growth. Results also illustrate that the majority of the future communication needs can be met using currently allocated aviation RF spectrum, if used in more effective ways than it is today. A combination of such optimized aviation-specific links and commercial communication systems meets all identified needs for the 50-year future and beyond, with the caveat that a new, overall function will be needed to manage all information exchange, individual links, security, cost, and other factors. This function was labeled "Delivery Manager" (DM

  2. Electricity competition and clean air

    International Nuclear Information System (INIS)

    The government of Ontario plans to establish a competitive market for the generation and sale of electricity by the year 2000, at which time Ontario Hydro will lose its monopoly. The government's rationale for moving to a competitive electricity market and the details of why this move could lead to a significant increase in air pollution was discussed. An overview of the health and environmental effects of electricity related air pollution was presented and the current national and provincial air quality objectives were outlined. The government of Ontario has promised that in implementing a competitive electricity market it will ensure that the province's environmental protection record is maintained and improved. It was suggested that in order to fulfill this commitment, new environmental regulations should be established to ensure that Ontario's total electricity-related emissions will decline when competition begins. Currently, air pollution from coal-fired power generating stations causes some of Ontario's most challenging health and environmental problems. Coal-fired generation stations are also major contributors to the build-up of greenhouse gases in the atmosphere. 74 refs., 2 tabs., 2 figs

  3. Report by the Commission of environment accounting and economy - Health and outdoor air quality

    International Nuclear Information System (INIS)

    After an overview of the issue of air pollution (definition, pollutant emission, population exposure, main air pollutants and emission sources, assessment of air quality in France), this report discusses the various impacts of air pollution on health and their related costs: pathologies associated with a bad air quality, categories which are more exposed than others, assessment of health impacts of air pollution, health costs. The next part describes the current policies aimed at improving air quality: European and international commitments, national policy, public policy tools, impacts of policies of struggle against air pollution by some pollutants, current researches and knowledge to be improved

  4. Diaphragms in air-operated valves

    International Nuclear Information System (INIS)

    The author will present current issues related to diaphgrams in air-operated valves. Altran Materials Engineering, Inc., often performs root-cause analyses for nuclear power plant owners. The author will discuss various analyses that have been performed or are currently underway

  5. Diaphragms in air-operated valves

    Energy Technology Data Exchange (ETDEWEB)

    Groeger, J.E.

    1996-12-01

    The author will present current issues related to diaphgrams in air-operated valves. Altran Materials Engineering, Inc., often performs root-cause analyses for nuclear power plant owners. The author will discuss various analyses that have been performed or are currently underway.

  6. Eddy current inspection of tubing

    International Nuclear Information System (INIS)

    The Experimental research work carried out to develop a Eddy current testing equipment is described. Search coils with ferrite or air cores were used and the obtained results are discussed. Valuable information was gained from a improved channel in which a direct measure of the defect and the reference signal phase difference is obtained. Artificial defect used to evaluate resolution and sensitivity were produced by electro-machining and mechanical means. Finned SAP tubing was tested in a routine basis with the described equipment and the results plotted. Basic and theoretical considerations on the Eddy current testing technique are given in the last section of this report. (Author)

  7. Indoor Air Quality

    OpenAIRE

    Korlakunta Divya #1, M.Anil Kumar

    2013-01-01

    The main aim of our project is to maintain the indoor air quality.The analysis is done on different parameters like temperature,relativehumidity,CO2,lights,sens ors and air conditioners to maintain the indoor environment.This report provides overview on importance of indoor air quality in an office or any other closed structure. It also discusses about the effects of poor indoor air quality, the various factors that affect the indoor air quality and various methods to assess indoor air qualit...

  8. Impact of Aircraft Performance Characteristics on Air Traffic Delays

    OpenAIRE

    Aydan CAVCAR; CAVCAR, Mustafa

    2004-01-01

    Air transportation has been suffering for decades from delays caused by air traffic congestion. This paper presents the effect of aircraft performance differences on air traffic delays. Rate of climb and cruising speeds of 70 different aircraft types are compared to demonstrate performance differences in the current transport aircraft fleet. The effect of these performance differences on air traffic delays is proved by a deterministic calculation of delays for a departure queue cons...

  9. The Economic Value of Air Quality Forecasting

    Science.gov (United States)

    Anderson-Sumo, Tasha

    Both long-term and daily air quality forecasts provide an essential component to human health and impact costs. According the American Lung Association, the estimated current annual cost of air pollution related illness in the United States, adjusted for inflation (3% per year), is approximately $152 billion. Many of the risks such as hospital visits and morality are associated with poor air quality days (where the Air Quality Index is greater than 100). Groups such as sensitive groups become more susceptible to the resulting conditions and more accurate forecasts would help to take more appropriate precautions. This research focuses on evaluating the utility of air quality forecasting in terms of its potential impacts by building on air quality forecasting and economical metrics. Our analysis includes data collected during the summertime ozone seasons between 2010 and 2012 from air quality models for the Washington, DC/Baltimore, MD region. The metrics that are relevant to our analysis include: (1) The number of times that a high ozone or particulate matter (PM) episode is correctly forecasted, (2) the number of times that high ozone or PM episode is forecasted when it does not occur and (3) the number of times when the air quality forecast predicts a cleaner air episode when the air was observed to have high ozone or PM. Our collection of data included available air quality model forecasts of ozone and particulate matter data from the U.S. Environmental Protection Agency (EPA)'s AIRNOW as well as observational data of ozone and particulate matter from Clean Air Partners. We evaluated the performance of the air quality forecasts with that of the observational data and found that the forecast models perform well for the Baltimore/Washington region and the time interval observed. We estimate the potential amount for the Baltimore/Washington region accrues to a savings of up to 5,905 lives and 5.9 billion dollars per year. This total assumes perfect compliance with

  10. OpenAIRE guidelines: supporting interoperability for Data Archives

    OpenAIRE

    Príncipe, Pedro; Nielsen, Lars Holm Nielsen; Rodrigues, Eloy; Schirrwagen, Jochen

    2015-01-01

    OpenAIRE supports the European Commission Open Access policy by providing an infrastructure for researchers to comply with the European Union Open Access mandate. The current OpenAIRE infrastructure and services, resulting from OpenAIRE and OpenAIREplus FP7 projects, builds on Open Access research results from a wide range of repositories and other data sources: institutional or thematic publication repositories, Open Access journals, data repositories, Current Research Information Systems...

  11. Air Quality Facilities

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Facilities with operating permits for Title V of the Federal Clean Air Act, as well as facilities required to submit an air emissions inventory, and other...

  12. Indoor Air Pollution

    Science.gov (United States)

    We usually think of air pollution as being outdoors, but the air in your house or office could also be polluted. Sources of indoor pollution include Mold and pollen Tobacco smoke Household products ...

  13. Allegheny County Air Quality

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Air quality data from Allegheny County Health Department monitors throughout the county. Air quality monitored data must be verified by qualified individuals...

  14. Nuclear air cleaning

    International Nuclear Information System (INIS)

    This report briefly describes the history of the use of high- efficiency particulate air filters for air cleaning at nuclear installations in the United States and discusses future uses of such filters

  15. Air Quality System (AQS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Air Quality System (AQS) database contains measurements of air pollutant concentrations from throughout the United States and its territories. The measurements...

  16. Air quality management planning (AQMP

    Directory of Open Access Journals (Sweden)

    Sivertsen Bjarne

    2012-01-01

    Full Text Available In most urban areas of the world, particulate matter (PM levels pose severe problems, addressed in several policy areas (air quality, climate change, and human health. PM presents multiple challenges due to the multitude of its sources, spanning many sectors of economic activity as well as nature, and due to the complexity of atmospheric processes involved in its transport and secondary formation. For the authorities, the goal is to assure minimal impacts of atmospheric PM levels, in practice represented by compliance with existing regulations and standards. This may be achieved through an air quality management plan (AQMP. In Northern America and in parts of Europe, comprehensive research programs have guided development of AQMP over the last forty years. This cumulated experience can be utilized by others who face the same problems, but have yet to develop their own substantial research base. The main purpose of the AQMP development process is to establish an effective and sound basis for planning and management of air quality in a selected area. This type of planning will ensure that significant sources of impacts are identified and controlled in a most cost-effective manner. The choice of tools, methods and input information is often dictated by their availability, and should be evaluated against current best practices. Important elements of the AQMP are the identification of sources and development of a complete emission inventory, the development and operation of an air quality monitoring programme, and the development and application of atmospheric dispersion models. Major task is to collect the necessary input data. The development of the AQMP will take into account: - Air Quality Management System (AQMS requirements; - Operational and functional structure requirements; - Source identification through emission inventories; - Source reduction alternatives, which may be implemented; - Mechanisms for facilitating interdepartmental

  17. Indoor air: Reference bibliography

    International Nuclear Information System (INIS)

    The U. S. Environmental Protection Agency initially established the indoor air Reference Bibliography in 1987 as an appendix to the Indoor Air Quality Implementation Plan. The document was submitted to Congress as required under Title IV--Radon Gas and Indoor Air Quality Research of the Superfund Amendments and Reauthorization Act of 1986. The Reference Bibliography is an extensive bibliography of reference materials on indoor air pollution. The Bibliography contains over 4500 citations and continues to increase as new articles appear

  18. Air-ion counter and mobility spectrometer

    International Nuclear Information System (INIS)

    Mono-electrode self “zeroing” air-ion counter and mobility (size) scanning spectrometer (CDI-011) based on the Gerdien aspirated condenser principle has been developed. Instrument is intended for short- and long-term indoor and outdoor air-ion concentration measurements and scanning of air-ions by mobility. Measuring small currents (typically 10−14 A) generated by the air-ions in outdoor conditions is demanding and causes many problems related to change of temperature, relative humidity, wind and electromagnetic noise. Also, measuring of both ion polarities with mono electrode detector require alternate changes of the polarizing voltage sign which produces capacitive current spikes. Various techniques, including “zeroing” method, have been applied to successfully overcome most of these measuring interferences.

  19. Air-ion counter and mobility spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Kolarz, Predrag, E-mail: kolarz@ipb.ac.rs [Institute of Physics, University of Belgrade, Pregrevica 118, 11080 Belgrade (Serbia); Miljkovic, Budimir [Merni Instrumenti D.O.O., Ljube Stojanovica 38, 11000 Belgrade (Serbia); Curguz, Zoran [Faculty of Transport and Traffic Engineering, University of East Sarajevo, Vojvode Misica 52, 74000 Doboj (Bosnia and Herzegowina)

    2012-05-15

    Mono-electrode self 'zeroing' air-ion counter and mobility (size) scanning spectrometer (CDI-011) based on the Gerdien aspirated condenser principle has been developed. Instrument is intended for short- and long-term indoor and outdoor air-ion concentration measurements and scanning of air-ions by mobility. Measuring small currents (typically 10{sup -14} A) generated by the air-ions in outdoor conditions is demanding and causes many problems related to change of temperature, relative humidity, wind and electromagnetic noise. Also, measuring of both ion polarities with mono electrode detector require alternate changes of the polarizing voltage sign which produces capacitive current spikes. Various techniques, including 'zeroing' method, have been applied to successfully overcome most of these measuring interferences.

  20. Air climate health

    International Nuclear Information System (INIS)

    'France Nature Environnement Ile de France' publishes, on occasion of the COP 21, a special paper about the air pollution in the Paris region, greenhouse gases and their influence on the environment. This document has been written in close cooperation with professionals and civil associations. Elected representatives from local and regional authorities also speak about their experiences. The first part emphasizes the urgency to accelerate preventive and corrective measures since the air pollution, after slightly decreasing in the 2000's, remains stable. Our work is a science based analysis of essential parameters and details the impact of local pollution and greenhouse gases on the climate. It is based on the GIEC 2013 and 2015 reports, as well as the work of National meteorology in association with the Climate agency of Paris. The threshold of not exceeding an average temperature of +2 deg. C in 2100 is almost reached. If consumption of fossil energies does not heavily decline in the next 10 years, the earth's thermal machine will enter, for several centuries, into an uncontrollable cycle which could endanger life on earth with average temperatures exceeding 4 to 6 deg. C above the current level. The second part reveals the impact of air pollution on the health of the Paris region's population, especially on women who are the most affected by respiratory diseases: obstructive pulmonary bronchitis and asthma. Four departments are particularly affected: Paris, Seine-et-Marne, Seine-Saint-Denis and Val-d'Oise. Even though we do not have the formal causal proof between gas concentration and disease, analysis of similar situations worldwide eliminate any doubts about the reality of the relationship. The third part proposes solutions which can be implemented by local government, companies, but also civil associations and citizens in order to quickly decrease greenhouse gas production. Solutions range from energy sobriety to change in travel

  1. Indoor Air Quality Manual.

    Science.gov (United States)

    Baldwin Union Free School District, NY.

    This manual identifies ways to improve a school's indoor air quality (IAQ) and discusses practical actions that can be carried out by school staff in managing air quality. The manual includes discussions of the many sources contributing to school indoor air pollution and the preventive planning for each including renovation and repair work,…

  2. Air Pollution Training Programs.

    Science.gov (United States)

    Public Health Service (DHEW), Rockville, MD.

    This catalog lists the universities, both supported and not supported by the Division of Air Pollution, which offer graduate programs in the field of air pollution. The catalog briefly describes the programs and their entrance requirements, the requirements, qualifications and terms of special fellowships offered by the Division of Air Pollution.…

  3. Indoor air quality

    DEFF Research Database (Denmark)

    Jensen, Trine Susanne; Recevska, Ieva

     The objective of the 35th specific agreement is to provide support to the EEA activities in Environment and Health (E&H) on the topic of indoor air quality. The specific objectives have been to provide an overview of indoor air related projects in EU and indoor air related policies as well...

  4. Indoor Air Pollution

    Science.gov (United States)

    We usually think of air pollution as being outdoors, but the air in your house or office could also be polluted. Sources of indoor pollution ... is known as sick building syndrome. Usually indoor air quality problems only cause discomfort. Most people feel ...

  5. Air Travel Health Tips

    Science.gov (United States)

    MENU Return to Web version Air Travel Health Tips Air Travel Health Tips How can I improve plane travel? Most people don't have any problems when ... and dosages of all of your medicines. The air in airplanes is dry, so drink nonalcoholic, decaffeinated ...

  6. We Pollute the Air

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    1.Clean air is important to good health.If the aircontains impurities,they may be absorbed by ourbodies and make us ill.We need clean air,butunfortunately,air pollution is generally present,especially in cities. 2.Our cities have many factories,which we need tomake food products,clothing and many other things.

  7. Microwave detection of air showers with MIDAS

    Energy Technology Data Exchange (ETDEWEB)

    Facal San Luis, P., E-mail: facal@kicp.uchicago.edu [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Alekotte, I. [Centro Atomico Bariloche and Instituto Balseiro (CNEA-UNCuyo-CONICET), 8400 San Carlos de Bariloche, Rio Negro (Argentina); Alvarez, J. [Universidad de Santiago de Compostela, Departamento de Fisica de Particulas, Campus Sur, E-15782 Santiago de Compostela (Spain); Berlin, A. [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Bertou, X. [Centro Atomico Bariloche and Instituto Balseiro (CNEA-UNCuyo-CONICET), 8400 San Carlos de Bariloche, Rio Negro (Argentina); Bogdan, M.; Bohacova, M. [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Bonifazi, C. [Univ. Federal do Rio de Janeiro (UFRJ), Instituto de Fisica, Cidade Universitaria, Caixa Postal 68528, 21945-970 Rio de Janeiro, RJ (Brazil); Carvalho, W.R. [Universidad de Santiago de Compostela, Departamento de Fisica de Particulas, Campus Sur, E-15782 Santiago de Compostela (Spain); Mello Neto, J.R.T. de [Univ. Federal do Rio de Janeiro (UFRJ), Instituto de Fisica, Cidade Universitaria, Caixa Postal 68528, 21945-970 Rio de Janeiro, RJ (Brazil); Genat, J.F.; Mills, E.; Monasor, M.; Privitera, P.; Reyes, I.C.; Rouille d& #x27; Orfeuil, B. [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); and others

    2012-01-11

    MIDAS (MIcrowave Detector of Air Showers) is a prototype of a microwave telescope to detect extensive air showers: it images a 20{sup Degree-Sign } Multiplication-Sign 10{sup Degree-Sign} region of the sky with a 4.5 m parabolic reflector and 53 feeds in the focal plane. It has been commissioned in March 2010 and is currently taking data. We present the design, performance and first results of MIDAS.

  8. Microwave detection of air showers with MIDAS

    Science.gov (United States)

    Facal San Luis, P.; Alekotte, I.; Alvarez, J.; Berlin, A.; Bertou, X.; Bogdan, M.; Bohacova, M.; Bonifazi, C.; Carvalho, W. R.; de Mello Neto, J. R. T.; Genat, J. F.; Mills, E.; Monasor, M.; Privitera, P.; Reyes, I. C.; Rouille D'Orfeuil, B.; Santos, E. M.; Wayne, S.; Williams, C.; Zas, E.

    2012-01-01

    MIDAS (MIcrowave Detector of Air Showers) is a prototype of a microwave telescope to detect extensive air showers: it images a 20°×10° region of the sky with a 4.5 m parabolic reflector and 53 feeds in the focal plane. It has been commissioned in March 2010 and is currently taking data. We present the design, performance and first results of MIDAS.

  9. Microwave detection of air showers with MIDAS

    International Nuclear Information System (INIS)

    MIDAS (MIcrowave Detector of Air Showers) is a prototype of a microwave telescope to detect extensive air showers: it images a 20°×10° region of the sky with a 4.5 m parabolic reflector and 53 feeds in the focal plane. It has been commissioned in March 2010 and is currently taking data. We present the design, performance and first results of MIDAS.

  10. Asthma aggravation, combustion, and stagnant air

    OpenAIRE

    Norris, G; Larson, T; Koenig, J.; Claiborn, C.; Sheppard, L; D. Finn

    2000-01-01

    BACKGROUND—The relationship between current concentrations of ambient air pollution and adverse health effects is controversial. We report a meteorological index of air stagnation that is associated with daily visits to the emergency department for asthma in two urban areas.
METHODS—Data on daily values of a stagnation persistence index and visits to the emergency department for asthma were collected for approximately two years in Spokane, Washington, USA and for 15months...

  11. Adiabatic Liquid Piston Compressed Air Energy Storage

    OpenAIRE

    Petersen, Tage; Elmegaard, Brian; Pedersen, Allan Schrøder

    2013-01-01

    This project investigates the potential of a Compressed Air Energy Storage system (CAES system). CAES systems are used to store mechanical energy in the form of compressed air. The systems use electricity to drive the compressor at times of low electricity demand with the purpose of converting the mechanical energy into electricity at times of high electricity demand. Two such systems are currently in operation; one in Germany (Huntorf) and one in the USA (Macintosh, Alabama). In both cases, ...

  12. Air-Breathing Rocket Engines

    Science.gov (United States)

    1998-01-01

    This photograph depicts an air-breathing rocket engine prototype in the test bay at the General Applied Science Lab facility in Ronkonkoma, New York. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced Space Transportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  13. Air Conditioning Does Reduce Air Pollution Indoors

    Science.gov (United States)

    Healy, Bud

    1970-01-01

    Report of the winter meeting of the American Society of Heating, Refrigerating and Air-Conditioning Engineers. Subjects covered are--(1) title subject, (2) predictions for the human habitat in 1994, (3) fans, and (4) fire safety in buildings. (JW)

  14. Biomonitoring of air quality using plants

    Energy Technology Data Exchange (ETDEWEB)

    Mulgrew, A.; Williams, P. [King' s Coll., London (United Kingdom). Monitoring and Assessment Research Centre - WHO Collaborating Centre for Monitoring and Assessment

    2000-02-01

    This report is an update of the MARC Report No. 32 'Biological Monitoring' and a first volume referring to a WHO project on biological monitoring. The monograph reviews comprehensively the existing literature on biological monitoring of air quality with plants. This review includes consideration of all plant species that are currently, or have a potential of, being used as bioindicators of air pollution. This review is intended to serve as a background paper for the derivation of guidelines for the use of biological monitors in air pollution control. (orig.)

  15. Advanced air distribution

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor

    2011-01-01

    The aim of total volume air distribution (TVAD) involves achieving uniform temperature and velocity in the occupied zone and environment designed for an average occupant. The supply of large amounts of clean and cool air are needed to maintain temperature and pollution concentration at acceptable....... Ventilation in hospitals is essential to decrease the risk of airborne cross-infection. At present, mixing air distribution at a minimum of 12 ach is used in infection wards. Advanced air distribution has the potential to aid in achieving healthy, comfortable and productive indoor environments at levels...... higher than what can be achieved today with the commonly used total volume air distribution principles....

  16. Air quality and future energy system planning

    Science.gov (United States)

    Sobral Mourao, Zenaida; Konadu, Dennis; Lupton, Rick

    2016-04-01

    Ambient air pollution has been linked to an increasing number of premature deaths throughout the world. Projected increases in demand for food, energy resources and manufactured products will likely contribute to exacerbate air pollution with an increasing impact on human health, agricultural productivity and climate change. Current events such as tampering emissions tests by VW car manufacturers, failure to comply with EU Air Quality directives and WHO guidelines by many EU countries, the problem of smog in Chinese cities and new industrial emissions regulations represent unique challenges but also opportunities for regulators, local authorities and industry. However current models and practices of energy and resource use do not consider ambient air impacts as an integral part of the planing process. Furthermore the analysis of drivers, sources and impacts of air pollution is often fragmented, difficult to understand and lacks effective visualization tools that bring all of these components together. This work aims to develop a model that links impacts of air quality on human health and ecosystems to current and future developments in the energy system, industrial and agricultural activity and patterns of land use. The model will be added to the ForeseerTM tool, which is an integrated resource analysis platform that has been developed at the University of Cambridge initially with funding from BP and more recently through the EPSRC funded Whole Systems Energy Modeling (WholeSEM) project. The basis of the tool is a set of linked physical models for energy, water and land, including the technologies that are used to transform these resources into final services such as housing, food, transport and household goods. The new air quality model will explore different feedback effects between energy, land and atmospheric systems with the overarching goal of supporting better communication about the drivers of air quality and to incorporate concerns about air quality into

  17. Released air during vapor and air cavitation

    Science.gov (United States)

    Jablonská, Jana; Kozubková, Milada

    2016-06-01

    Cavitation today is a very important problem that is solved by means of experimental and mathematical methods. The article deals with the generation of cavitation in convergent divergent nozzle of rectangular cross section. Measurement of pressure, flow rate, temperature, amount of dissolved air in the liquid and visualization of cavitation area using high-speed camera was performed for different flow rates. The measurement results were generalized by dimensionless analysis, which allows easy detection of cavitation in the nozzle. For numerical simulation the multiphase mathematical model of cavitation consisting of water and vapor was created. During verification the disagreement with the measurements for higher flow rates was proved, therefore the model was extended to multiphase mathematical model (water, vapor and air), due to release of dissolved air. For the mathematical modeling the multiphase turbulence RNG k-ɛ model for low Reynolds number flow with vapor and air cavitation was used. Subsequently the sizes of the cavitation area were verified. In article the inlet pressure and loss coefficient depending on the amount of air added to the mathematical model are evaluated. On the basis of the approach it may be create a methodology to estimate the amount of released air added at the inlet to the modeled area.

  18. Manual for THOR-AirPAS - air pollution assessment system

    DEFF Research Database (Denmark)

    Jensen, Steen Solvang; Ketzel, Matthias; Brandt, Jørgen;

    The report provides an outline of the THOR-AirPAS - air pollution assessment system and a brief manual for getting started with the air quality models and input data included in THOR-AirPAS.......The report provides an outline of the THOR-AirPAS - air pollution assessment system and a brief manual for getting started with the air quality models and input data included in THOR-AirPAS....

  19. ATMOSPHERIC AIR QUALITY IN CALARASI TOWN

    Directory of Open Access Journals (Sweden)

    Cecilia NEAGU

    2013-01-01

    Full Text Available The present paper seeks to highlight the appearance of air pollution in Calarasi region on the basis of the annual reports of the environment in recent years and of the integrated air quality management for Cǎlǎraşi (data are presented about current and future emissions and concentrations of pollutants I tried to mark out the impurity of the atmospheric air from this area.Emission data interpretation was made on the basis of the inventory of emissions of pollutants in the air made for fixed and mobile sources in Calarasi town in recent years using the program Corinvent and Corinair emission factors, and imissions data were used to monitor the air quality monitoring network air quality. The index of the quality of the air showed the highest values in winter.There have been occasional instances of the limit provided by law for particulate matter PM10, Calarasi, or being the intense traffic, the topoclimate in summer periods with high temperatures and deficient pluviometric regime, but also because housing fuel winter warming solid. There major problems of environmental pollution of air quality in Calarasi town that falls within the limits imposed by the legislation in force. This is due especially to the fact that many industrial centres have been closed.

  20. State of the air in British Columbia

    International Nuclear Information System (INIS)

    Scientific evidence is rising regarding the danger of air pollution. Poor air quality can pose a problem in British Columbia, particularly in interior communities when temperature inversions, during certain times of the year, trap pollutants in mountain valleys. This document described where pollutants come from, ambient levels in the atmosphere and how they affect human health. Particular focus was on fine particulate matter, ozone and oxides of nitrogen, as these 3 pollutants have been linked to health impacts. The cost of air pollution through increased health care costs and the economic impact of lost productivity from missed work days was also discussed along with the influence of poor air quality on crop damage and forestry production losses. The document also outlined government and community initiatives to protect public health and listed some measures that individuals can do to keep air clean. Air pollution stems from activities such as land development, burning fossil fuels for energy and transportation, industrial operations, residential wood burning and backyard burning of debris and burning from forestry and agricultural operations. The health impacts range from irritation, to coughing and worsening of existing heart and lung conditions. The document states that despite all measures being taken to reduce emissions and to maintain levels of air pollutants at current low levels, health effects are still observed and still pose a burden to health care cost. Scientific evidence indicates that a further reduction in air pollution will result in health benefits. refs., figs

  1. Senate passes clean air bill

    Science.gov (United States)

    In an 89 to 11 vote the Senate passed a clean air bill aimed at reducing pollution by the turn of the century by imposing tougher controls on American industry. The bill is the first revision of the Clean Air Act of 1970 in 13 years and calls for new limits on auto pollution to clean up smog in most U.S. cities, decreasing by half emissions by power plants that cause acid rain to protect the ecology, and increasing technological controls on factories to protect against cancer-causing and toxic substances. The bill will add about $20 billion per year to the estimated $33 billion cost of complying with current pollution laws.

  2. Standards for air monitoring calibration

    International Nuclear Information System (INIS)

    The US Department of Energy and the US Nuclear Regulatory Commission initiated a joint program to test the applicability of a performance-type testing standard. Draft American National Standards Institute (ANSI) Standard N42.17a was, because of difficulty in application, divided into three parts: (a) portable instruments, (b) air monitors, and (c) extended range. This new testing program used the criteria listed in parts a, b, and c to determine whether they could be used as the basis of an instrument qualification testing program. The results of the test were then provided to the standards committee, and appropriate changes were made in the standard. The detailed results of this testing program will be documented in the future. The purpose of this presentation is to discuss the current draft of the air monitoring standard, general test procedures, results of some of the tests, and the means by which the testing program could be implemented in the United States

  3. Health Effects of Air Pollution

    Science.gov (United States)

    ... air pollution How to protect yourself from air pollution Chemicals Noise Quizzes Links to more information girlshealth glossary girlshealth.gov home http://www.girlshealth.gov/ Home The environment and your health Air Health effects of air pollution ... Health effects of air pollution Breathing air that ...

  4. Air filtration in HVAC systems

    CERN Document Server

    Ginestet, Alain; Tronville, Paolo; Hyttinen, Marko

    2010-01-01

    Air filtration Guidebook will help the designer and user to understand the background and criteria for air filtration, how to select air filters and avoid problems associated with hygienic and other conditions at operation of air filters. The selection of air filters is based on external conditions such as levels of existing pollutants, indoor air quality and energy efficiency requirements.

  5. Overview of NASA's Next Generation Air Transportation System (NextGen) Research

    Science.gov (United States)

    Swenson, Harry N.

    2009-01-01

    This slide presentation is an overview of the research for the Next Generation Air Transportation System (NextGen). Included is a review of the current air transportation system and the challenges of air transportation research. Also included is a review of the current research highlights and significant accomplishments.

  6. Air Quality in Lithuania

    Energy Technology Data Exchange (ETDEWEB)

    Pietilae, P. [Tampere University of Technology / ECAT-Lithuania (Lithuania); Kliucininkas, L. [Department for Environmental Engineering, Kaunas University of Technology (Lithuania)

    2000-07-01

    Sustainable monitoring of the ambient air is the major preventive measure of ensuring its proper quality. Only with a monitoring procedure going-on a continuous basis it is possible to make an objective evaluation of air pollution trends, of the efficiency of air protection measures and, partially, to a certain extent of the impact the pollution exerts on a human health. The information stemming from the monitoring procedure must be reliable, sustainable and efficient. (orig.)

  7. Indonesia's Clean Air Program

    OpenAIRE

    Budy P. Resosudarmo

    2002-01-01

    Unprecedented industrial development in Indonesia during the last two decades, accompanied by a growing population, has increased the amount of environmental damage. One of the most important environmental problems is that the level of air pollution in several large cities has become alarming, particularly in the last few years. This high pollution level has stimulated the government to develop a national clean air program designed to control the quantity of pollutants in the air. However, th...

  8. Emergency air supply

    International Nuclear Information System (INIS)

    An air supply safety device is described which can operate in an hostile environment. The system ensures that should the ring mains supply or the operator's individual hose fail an emergency air supply is obtained from a compressed air bottle fed to the operator's face mask via a valve. The valve switches from mains/mask to emergency supply/mask when the mains pressure falls below the emergency supply pressure. (U.K.)

  9. Radioactive material air transportation

    International Nuclear Information System (INIS)

    As function of the high aggregated value, safety regulations and the useful life time, the air transportation has been used more regularly because is fast, reliable, and by giving great security to the cargo. Based on the International Atomic Energy Agency (IAEA), the IATA (International Air Transportation Association) has reproduced in his dangerous goods manual (Dangerous Goods Regulations - DGR IATA), the regulation for the radioactive material air transportation. Those documents support this presentation

  10. Electric air filtration movie

    International Nuclear Information System (INIS)

    The use of electrostatics to improve the performance of conventional air filters has gained considerable attention in recent years. This interest is due to the higher efficiency and reduced pressure drop of electrically enhanced filters compared to conventional fibrous filters. This 30-minute movie presents a state of the art review of electric air filters in the United States with major illustrations provided by the research and development program at the Lawrence Livermore National Laboratory sponsored by the Department of Energy. The electric air filters described in this movie are mechanical air filters to which electrical forces have been added

  11. Applications Using AIRS Data

    Science.gov (United States)

    Ray, S. E.; Pagano, T. S.; Fetzer, E. J.; Lambrigtsen, B.; Olsen, E. T.; Teixeira, J.; Licata, S. J.; Hall, J. R.; Thompson, C. K.

    2015-12-01

    The Atmospheric Infrared Sounder (AIRS) on NASA's Aqua spacecraft has been returning daily global observations of Earth's atmospheric constituents and properties since 2002. With a 12-year data record and daily, global observations in near real-time, AIRS data can play a role in applications that fall under many of the NASA Applied Sciences focus areas. For vector-borne disease, research is underway using AIRS near surface retrievals to assess outbreak risk, mosquito incubation periods and epidemic potential for dengue fever, malaria, and West Nile virus. For drought applications, AIRS temperature and humidity data are being used in the development of new drought indicators and improvement in the understanding of drought development. For volcanic hazards, new algorithms using AIRS data are in development to improve the reporting of sulfur dioxide concentration, the burden and height of volcanic ash and dust, all of which pose a safety threat to aircraft. In addition, anomaly maps of many of AIRS standard products are being produced to help highlight "hot spots" and illustrate trends. To distribute it's applications imagery, AIRS is leveraging existing NASA data frameworks and organizations to facilitate archiving, distribution and participation in the BEDI. This poster will communicate the status of the applications effort for the AIRS Project and provide examples of new maps designed to best communicate the AIRS data.

  12. Air pollution meteorology

    International Nuclear Information System (INIS)

    This report is intended as a training cum reference document for scientists posted at the Environmental Laboratories at the Nuclear Power Station Sites and other sites of the Department of Atomic Energy with installations emitting air pollutants, radioactive or otherwise. Since a manual already exists for the computation of doses from radioactive air pollutants, a general approach is take here i.e. air pollutants in general are considered. The first chapter presents a brief introduction to the need and scope of air pollution dispersion modelling. The second chapter is a very important chapter discussing the aspects of meteorology relevant to air pollution and dispersion modelling. This chapter is important because without this information one really does not understand the phenomena affecting dispersion, the scope and applicability of various models or their limitations under various weather and site conditions. The third chapter discusses the air pollution models in detail. These models are applicable to distances of a few tens of kilometres. The fourth chapter discusses the various aspects of meteorological measurements relevant to air pollution. The chapters are followed by two appendices. Apendix A discusses the reliability of air pollution estimates. Apendix B gives some practical examples relevant to general air pollution. It is hoped that the document will prove very useful to the users. (author)

  13. Tubular solid oxide fuel cell current collector

    Science.gov (United States)

    Bischoff, Brian L.; Sutton, Theodore G.; Armstrong, Timothy R.

    2010-07-20

    An internal current collector for use inside a tubular solid oxide fuel cell (TSOFC) electrode comprises a tubular coil spring disposed concentrically within a TSOFC electrode and in firm uniform tangential electrical contact with the electrode inner surface. The current collector maximizes the contact area between the current collector and the electrode. The current collector is made of a metal that is electrically conductive and able to survive under the operational conditions of the fuel cell, i.e., the cathode in air, and the anode in fuel such as hydrogen, CO, CO.sub.2, H.sub.2O or H.sub.2S.

  14. LAAS network observation of air showers

    International Nuclear Information System (INIS)

    A network observation of air showers is in progress in Japan. Researchers from 10 institutions are taking part in the network, forming the Large Area Air Shower (LAAS) group. As of June 2000, eight air shower arrays (stations) are in operation, while five more stations are under construction. The stations are scattered over an enormous area of 130,000 km2, however the Global Positioning System (GPS) provides comparable time stamps among them with an accuracy of one microsecond. The aim of the network is to find out correlations in primary cosmic rays just below the knee. The data from the planned Norikura array (2,770 m a.s.l.) is expected to reveal new aspects of correlated cosmic rays. The current status of the network and performance of arrays calculated by the air shower simulation code CORSIKA are described here

  15. Formal Methods Applications in Air Transportation

    Science.gov (United States)

    Farley, Todd

    2009-01-01

    The U.S. air transportation system is the most productive in the world, moving far more people and goods than any other. It is also the safest system in the world, thanks in part to its venerable air traffic control system. But as demand for air travel continues to grow, the air traffic control system s aging infrastructure and labor-intensive procedures are impinging on its ability to keep pace with demand. And that impinges on the growth of our economy. Air traffic control modernization has long held the promise of a more efficient air transportation system. Part of NASA s current mission is to develop advanced automation and operational concepts that will expand the capacity of our national airspace system while still maintaining its excellent record for safety. It is a challenging mission, as efforts to modernize have, for decades, been hamstrung by the inability to assure safety to the satisfaction of system operators, system regulators, and/or the traveling public. In this talk, we ll provide a brief history of air traffic control, focusing on the tension between efficiency and safety assurance, and the promise of formal methods going forward.

  16. A study of lithium air rechargeable batteries

    International Nuclear Information System (INIS)

    Lithium air battery system electro-chemically couples lithium metal anode to atmospheric oxygen through an air cathode. Due to the fact that the only electrolyte composition aprotic (proton donor) of lithium-air battery has shown the best refillable electric power, has attracted the electrical system in all parts of the world even more effort now. Aprotic electrolytes which are used include organic carbonates (e.g. ethylene carbonate. dimethyl carbonate, propylene carbonate), or ethers (tetrahydrofuran (THF), dioxolane) or esters (γ-butyrolactone), Manganese dioxide catalyzed porous carbon cathode. PVDF (Polyvinylidene fluoride) binder. Teflon (PTFE) membrane is normally deposited on air side of cathode to control moisture penetration in it. Lithium salts, such as LiN (SO/sub 2/CF/sub 3/),/sub 2/, LiSO/sub 3/CF/sub 3/, LiPF/sub 6/, LiAsF/sub 6/ can be used in electrolyte to improve their conductivity. Polyethylene terephthalate layers or polypropylene layer are normally used as casing material whereas Nickel foam is used as current collector material. It is noted from the literature that Gold and Platinum enhance the charge discharge efficiency as catalysts. Most of the research on lithium air batteries has its focus on developing lithium air batteries for hybrid transportation vehicles. High reactivity of pure metallic lithium anode creates the major safety concerns. Nowadays research is mainly focused on developing certain protective mechanism to overcome this hindrance in the commercialization of lithium air batteries. (author)

  17. Research review: Indoor air quality control techniques

    International Nuclear Information System (INIS)

    Techniques for controlling the concentration of radon, formaldehyde, and combustion products in the indoor air are reviewed. The most effective techniques, which are generally based on limiting or reducing indoor pollutant source strengths, can decrease indoor pollutant concentrations by a factor of 3 to 10. Unless the initial ventilation rate is unusually low, it is difficult to reduce indoor pollutant concentrations more than approximately 50% by increasing the ventilation rate of an entire building. However, the efficiency of indoor pollutant control by ventilation can be enhanced through the use of local exhaust ventilation near concentrated sources of pollutants, by minimizing short circuiting of air from supply to exhaust when pollutant sources are dispersed and, in some situations, by promoting a displacement flow of air and pollutants toward the exhaust. Active air cleaning is also examined briefly. Filtration and electrostatic air cleaning for removal of particles from the indoor air are the most practical and effective currently available techniques of air cleaning. 49 refs., 7 figs

  18. Dynamic Density: An Air Traffic Management Metric

    Science.gov (United States)

    Laudeman, I. V.; Shelden, S. G.; Branstrom, R.; Brasil, C. L.

    1998-01-01

    The definition of a metric of air traffic controller workload based on air traffic characteristics is essential to the development of both air traffic management automation and air traffic procedures. Dynamic density is a proposed concept for a metric that includes both traffic density (a count of aircraft in a volume of airspace) and traffic complexity (a measure of the complexity of the air traffic in a volume of airspace). It was hypothesized that a metric that includes terms that capture air traffic complexity will be a better measure of air traffic controller workload than current measures based only on traffic density. A weighted linear dynamic density function was developed and validated operationally. The proposed dynamic density function includes a traffic density term and eight traffic complexity terms. A unit-weighted dynamic density function was able to account for an average of 22% of the variance in observed controller activity not accounted for by traffic density alone. A comparative analysis of unit weights, subjective weights, and regression weights for the terms in the dynamic density equation was conducted. The best predictor of controller activity was the dynamic density equation with regression-weighted complexity terms.

  19. Restoran Buenos Aires = Restaurant Buenos Aires

    Index Scriptorium Estoniae

    2008-01-01

    Restorani Buenos Aires (Narva mnt. 5, Tallinn) sisekujundusest. Sisearhitektid: Janno Roos ja Andres Labi (Ruumilabor OÜ). Laudu eraldavad 400 vardasse aetud puukuuli. Sisearhitektidest, nende tähtsamad tööd. I-III korruse plaan, 12 värv. vaadet, fotod sisearhitektidest

  20. Infectious Risks of Air Travel.

    Science.gov (United States)

    Mangili, Alexandra; Vindenes, Tine; Gendreau, Mark

    2015-10-01

    Infectious diseases are still among the leading causes of death worldwide due to their persistence, emergence, and reemergence. As the recent Ebola virus disease and MERS-CoV outbreaks demonstrate, the modern epidemics and large-scale infectious outbreaks emerge and spread quickly. Air transportation is a major vehicle for the rapid spread and dissemination of communicable diseases, and there have been a number of reported outbreaks of serious airborne diseases aboard commercial flights including tuberculosis, severe acute respiratory syndrome, influenza, smallpox, and measles, to name a few. In 2014 alone, over 3.3 billion passengers (a number equivalent to 42% of the world population) and 50 million metric tons of cargo traveled by air from 41,000 airports and 50,000 routes worldwide, and significant growth is anticipated, with passenger numbers expected to reach 5.9 billion by 2030. Given the increasing numbers of travelers, the risk of infectious disease transmission during air travel is a significant concern, and this chapter focuses on the current knowledge about transmission of infectious diseases in the context of both transmissions within the aircraft passenger cabin and commercial aircraft serving as vehicles of worldwide infection spread. PMID:26542037

  1. Air pollution and society

    OpenAIRE

    Brimblecombe P.

    2010-01-01

    Air pollution is as much a product of our society as it is one of chemistry and meteorology. Social variables such as gender, age, health status and poverty are often linked with our exposure to air pollutants. Pollution can also affect our behaviour, while regulations to improve the environment can often challenge of freedom.

  2. AIR RADIOACTIVITY MONITOR

    Science.gov (United States)

    Bradshaw, R.L.; Thomas, J.W.

    1961-04-11

    The monitor is designed to minimize undesirable background buildup. It consists of an elongated column containing peripheral electrodes in a central portion of the column, and conduits directing an axial flow of radioactively contaminated air through the center of the column and pure air through the annular portion of the column about the electrodes. (AEC)

  3. Air Pollution, Teachers' Edition.

    Science.gov (United States)

    Lavaroni, Charles W.; O'Donnell, Patrick A.

    One of three in a series about pollution, this teacher's guide for a unit on air pollution is designed for use in junior high school grades. It offers suggestions for extending the information and activities contained in the textual material for students. Chapter 1 discusses the problem of air pollution and involves students in processes of…

  4. International Air Services

    OpenAIRE

    Productivity Commission

    2001-01-01

    On 12 December 1997 the Treasurer referred international air services arrangements to the Industry Commission for inquiry and report within nine months. The Commission was asked to report on the arrangements for negotiating entitlements under air services agreements and the process of allocating capacity entitlements to Australian carriers.

  5. Energy and air quality

    International Nuclear Information System (INIS)

    This is one of a series of handbooks designed to provide nontechnical readers with a general understanding of the interaction between energy development and environmental media and to provide a rudimentary data base from which estimates of potential future impacts can be made. This handbook describes the air quality impacts of energy development and summarizes the major federal legislation which regulates the potential air quality impacts of energy facilities and can thus influence the locations and timing of energy development. In addition, this report describes and presents the data which can be used as the basis for measurement, and in some cases, prediction of the potential conflicts between energy development and achieving and maintaining clean air. Energy utilization is the largest emission source of man-made air pollutants. Choices in energy resource development and utilization generate varying emissions or discharges into the atmosphere, the emissions are affected by the assimilative character of the atmosphere, and the resultant air pollutant concentrations have biological and aesthetic effects. This handbook describes the interrelationships of energy-related air emissions under various methods of pollution control, the assimilative character of the air medium, and the effects of air pollution. The media book is divided into three major sections: topics of concern relating to the media and energy development, descriptions of how to use available data to quantify and examine energy/environmental impacts, and the data

  6. Air Pollution Primer.

    Science.gov (United States)

    National Tuberculosis and Respiratory Disease Association, New York, NY.

    As the dangers of polluted air to the health and welfare of all individuals became increasingly evident and as the complexity of the causes made responsibility for solutions even more difficult to fix, the National Tuberculosis and Respiratory Disease Association felt obligated to give greater emphasis to its clean air program. To this end they…

  7. Over the air test

    DEFF Research Database (Denmark)

    2015-01-01

    [1] This invention relates to over-the-air testing of a device in an anechoic chamber. In particular, the invention is suitable for simulating both uplink and downlink over-the-air communication with a device under test even when the anechoic chamber has different numbers of uplink and downlink...

  8. Use of the Operational Air Quality Monitor (AQM) for In-Flight Water Testing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Currently, the Air Quality Monitor (AQM) on-board ISS provides specific information for a number of target compounds in the air. However, there is a significant...

  9. Bio-Electrochemical Carbon Dioxide Removal for Air Revitalization in Exploration Life Support Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An important aspect of the ISS air revitalization system for life support is the removal of carbon dioxide from cabin air and retrieves oxygen from CO2. The current...

  10. Air pollution and air cleaning equipment in buildings

    OpenAIRE

    Evdokimova, Ekaterina

    2011-01-01

    The subject of this thesis work is air pollution and air cleaners in building. Clean air has big significance for human health because different pollutions can cause allergy and disease. The quality of indoor air affects health and effective working. The aim of this thesis is to present methods and devices for cleaning the air.

  11. PREV'AIR : an operational forecasting and mapping system for air quality in Europe

    OpenAIRE

    Rouil, Laurence; Honore, Cécile; Vautard, Robert; Beekmann, Matthias; Bessagnet, Bertrand; Malherbe, Laure; Meleux, Frédérik; Dufour, Anne; Elichegaray, Christian; Flaud, Jean-Marie; Menut, Laurent; Martin, Daniel; Peuch, Aline; Peuch, Vincent-Henri; Poisson, Nathalie

    2009-01-01

    The current state of the art in three-dimensional chemistry-transport models allows them to be considered as mature and reliable enough to be combined with observations networks for implementing integrated air quality monitoring systems over large territories. A cooperative initiative of four research and operational organizations in France has led to the creation of an integrated air quality platform providing near-real-time and forecasted information using last model developments. Since sum...

  12. Current distribution characteristics of superconducting parallel circuits

    International Nuclear Information System (INIS)

    In order to increase the current carrying capacity of the current path of the superconducting magnet system, the portion of parallel circuits such as insulated multi-strand cables or parallel persistent current switches (PCS) are made. In superconducting parallel circuits of an insulated multi-strand cable or a parallel persistent current switch (PCS), the current distribution during the current sweep, the persistent mode, and the quench process were investigated. In order to measure the current distribution, two methods were used. (1) Each strand was surrounded with a pure iron core with the air gap. In the air gap, a Hall probe was located. The accuracy of this method was deteriorated by the magnetic hysteresis of iron. (2) The Rogowski coil without iron was used for the current measurement of each path in a 4-parallel PCS. As a result, it was shown that the current distribution characteristics of a parallel PCS is very similar to that of an insulated multi-strand cable for the quench process

  13. Current Status of Radioisotope Applications in Defence

    Directory of Open Access Journals (Sweden)

    P. K. Bhatnagar

    1987-07-01

    Full Text Available Reviews the current status of radioisotope applications in Defence- R&D Establishments, Defence Inspectorates, Ordnance Factories, Public Sector Undertakings under the Defence Ministry, Army, Navy and Air Force Establishments and Military Hospitals. It also lists the users of film badge service in Defence. Training programmes in radioisotope applications in Defence conducted by DRDO organisations have also been highlighted.

  14. Teaching Tips on Current Environmental Problems.

    Science.gov (United States)

    Busch, Phyllis S.

    This manual, prepared by the Science Project Related to Upgrading Conservation Education (Project S.P.R.U.C.E.), contains suggestions for introducing elementary school students to current environmental problems. Problems treated are population density, social pollution, visual pollution, air pollution, and water pollution. A background discussion…

  15. Current and temperature structure of Rihand Lake

    Digital Repository Service at National Institute of Oceanography (India)

    Suryanarayana, A.; Swamy, G.N.; Sadhuram, Y.

    The environmental parameters such as wind, water and air temperatures, and currents were measured in Rihand Lake, Madhya Pradesh, India during the hotest months, May-June of 1983. Rihand is an artificial lake having an area of 300 km super(2...

  16. Exercise and outdoor ambient air pollution

    OpenAIRE

    Carlisle, A.; Sharp, N

    2001-01-01

    Objectives—To establish by literature survey: (a) levels at which air pollutants are considered damaging to human health and to exercisers in particular; (b) the current ambient levels experienced in the United Kingdom; (c) whether athletes are especially at risk.

  17. Short-term airing by natural ventilation

    DEFF Research Database (Denmark)

    Perino, Marco; Heiselberg, Per

    2009-01-01

    traditional mechanical ventilation components with natural ventilation devices, such as motorized windows and louvers. Among the various ventilation strategies that are currently available, buoyancy driven single-sided natural ventilation has proved to be very effective and can provide high air change rates...

  18. The Conquest of Air and Space

    Science.gov (United States)

    Eisley, J. G.

    1971-01-01

    Describes a course for non-engineering students as an introduction to: (1) the physical principles of flight within the atmosphere and in space, (2) the major historical developments in the conquest of air and space, and (3) the current state of aeronautical developments. (Author/TS)

  19. Cooling efficiency of a brushless direct current stand fan

    OpenAIRE

    Yang, Bin; Schiavon, Stefano; Sekhar, Chandra; Cheong, David; Tham, Kwok Wai; Nazaroff, William W.

    2015-01-01

    In warm environments, isothermal cooling by deliberately enhanced air movement can maintain thermal comfort using less energy than compressor-based air conditioning. To evaluate the performance of a brushless direct current (DC) stand fan, the cooling fan efficiency (CFE) index was measured in a climatic chamber under four dry-bulb temperatures (24, 26, 28, and 30 °C), six speed In warm environments, isothermal cooling by deliberately enhanced air movement can maintain thermal comfort using l...

  20. Hydrodynamic modeling of semi-planing hulls with air cavities

    Directory of Open Access Journals (Sweden)

    Matveev Konstantin I.

    2015-05-01

    Full Text Available High-speed heavy loaded monohull ships can benefit from application of drag-reducing air cavities under stepped hull bottoms. The subject of this paper is the steady hydrodynamic modeling of semi-planing air-cavity hulls. The current method is based on a linearized potential-flow theory for surface flows. The mathematical model description and parametric calculation results for a selected configuration with pressurized and open air cavities are presented.

  1. Assessment of Air Quality Status in Wuhan, China

    OpenAIRE

    Jiabei Song; Wu Guang; Linjun Li; Rongbiao Xiang

    2016-01-01

    In this study, air quality characteristics in Wuhan were assessed through descriptive statistics and Hierarchical Cluster Analysis (HCA). Results show that air quality has slightly improved over the recent years. While the NO2 concentration is still increasing, the PM10 concentration shows a clearly downward trend with some small fluctuations. In addition, the SO2 concentration has steadily decreased since 2008. Nevertheless, the current level of air pollutants is still quite high, with the P...

  2. Public attitudes to air pollution from road vehicles

    OpenAIRE

    Ian D. Williams

    1994-01-01

    An assessment of the environmental effects of any new road scheme is currently recommended by the Department of Transport, but the existing appraisal does not include an evaluation of public nuisance from vehicle-derived air pollution. This research project has investigated the subjective nuisance effects of air pollution from road traffic on the public through the simultaneous measurement of public attitudes towards vehicle-generated nuisance and air quality in residential and commercial are...

  3. Aircraft Recirculation Filter for Air-Quality and Incident Assessment

    OpenAIRE

    Eckels, Steven J.; Jones, Byron; Mann, Garrett; Mohan, Krishnan R.; Weisel, Clifford P.

    2014-01-01

    The current research examines the possibility of using recirculation filters from aircraft to document the nature of air-quality incidents on aircraft. These filters are highly effective at collecting solid and liquid particulates. Identification of engine oil contaminants arriving through the bleed air system on the filter was chosen as the initial focus. A two-step study was undertaken. First, a compressor/bleed air simulator was developed to simulate an engine oil leak, and samples were an...

  4. The air pollution index system in Hong Kong

    Energy Technology Data Exchange (ETDEWEB)

    Lee, F.Y.P.; Gervat, G.P. [Hong Kong Government, Wanchai (Hong Kong). Environmental Protection Dept.

    1995-12-31

    The Hong Kong Environmental Protection Department (EPD) is currently operating an air quality monitoring network in the territory. There are nine monitoring stations, each with air quality monitoring equipment, meteorological instruments and a data logger. Five minute averaged data are transmitted through telephone lines to the central computer at the EPD Air Laboratory and are also stored in the data logger on site, as backup. At present, the EPD releases its air quality measurements to the public via monthly and special press releases, and annual reports. However, as public awareness of air pollution problems has increased, there has been an urgent need for timely and simpler information about air pollution levels. The development and operation of an Air Pollution Index (API) system has addressed that need. This presentation discusses the API computation, the information and advice released to the general public and how they can access the API information. Some API results are also presented. (author)

  5. Air Baltic: Estonian Air on nurka surutud / Teele Tammeorg

    Index Scriptorium Estoniae

    Tammeorg, Teele

    2010-01-01

    Air Balticu asepresidendi Janis Vanagsi hinnangul on Estonian Air aastaid jätnud tähelepanuta oma peamised turismiturud ning on praegu halvas seisus. Air Baltic on endiselt huvitatud Estonian Airi ostust. Majandus- ja kommunikatsiooniminister Juhan Partsi seisukoht

  6. The current catalog--how current?

    Science.gov (United States)

    Sargent, C W

    1968-07-01

    NLM's Current Catalog has recently come in for some criticism. To be useful as a tool in acquisition and cataloging, currency in receipt of the Current Catalog is necessary. A survey of 263 titles with 1967 imprints, which were received by the Library of the Medical Sciences, University of New Mexico School of Medicine, was made to determine the correlation between the receipt of these books in the library and their appearance in the Current Catalog. PMID:5695111

  7. CityAir app: Mapping air-quality perception using people as sensors

    Science.gov (United States)

    Castell, Nuria; Fredriksen, Mirjam; Cole-Hunter, Thomas; Robinson, Johanna; Keune, Hans; Nieuwenhuijsen, Mark; Bartonova, Alena

    2016-04-01

    Outdoor air pollution is a major environmental health problem affecting all people in developed and developing countries alike. Ambient (outdoor) air pollution in both cities and rural areas was estimated to cause 3.7 million premature deaths worldwide in 2012. In modern society, people are expending an increasing amount of time in polluted urban environments, thus increasing their exposure and associated health responses. Some cities provide information about air pollution levels to their citizens using air quality monitoring networks. However, due to their high cost and maintenance, the density of the monitoring networks is very low and not capable to capture the high temporal and spatial variability of air pollution. Thus, the citizen lacks a specific answer to the question of "how the air quality is in our surroundings". In the framework of the EU-funded CITI-SENSE project the innovative concept of People as Sensors is being applied to the field of outdoor air pollution. This is being done in eight European cities, including Barcelona, Belgrade, Edinburgh, Haifa, Ljubljana, Oslo, Ostrava and Vienna. People as Sensors defines a measurement model, in which measurements are not only taken by hardware sensors, but in which also humans can contribute with their individual "measurements" such as their subjective perception of air quality and other personal observations. In order to collect the personal observations a mobile app, CityAir, has been developed. CityAir allows citizens to rate the air quality in their surroundings with colour at their current location: green if air quality is very good, yellow if air quality is good, orange if air quality is poor and red if air quality is very poor. The users have also the possibility of indicating the source of pollution (i.e. traffic, industry, wood burning) and writing a comment. The information is on-line and accessible for other app users, thus contributing to create an air-quality map based on citizens' perception

  8. Monitoring tritium in air containing other radioactive gases

    International Nuclear Information System (INIS)

    A brief survey is presented of methods that have been developed for active tritium monitoring that may be applied to measure tritium concentrations in air containing 13N, 16N, and 41Ar produced by D-T neutrons. Included are instruments that employ current subtraction to achieve discriminations and others that selectively remove atmospheric water vapor from stream of activated air

  9. Demonstrations of Magnetic Phenomena: Measuring the Air Permeability Using Tablets

    Science.gov (United States)

    Lara, V. O. M.; Amaral, D. F.; Faria, D.; Vieira, L. P.

    2014-01-01

    We use a tablet to experimentally determine the dependencies of the magnetic field (B) on the electrical current and the axial distance from a coil (z). Our data shows good precision on the inverse cubic dependence of the magnetic field on the axial distance, B?z[superscript -3]. We obtain the value of air permeability µ[subscript air] with good…

  10. Evaluation of reciprocating electromagnetic air pumping for portable PEMFC

    International Nuclear Information System (INIS)

    In this paper, we present a proton exchange membrane fuel cell (PEMFC) integrated with an electromagnetic (EM) air pump. The EM air pump provides the PEMFC with air by reciprocating motions of the permanent magnet attached to a flexible membrane. We performed a parametric study to decide the optimal dimensions of the reciprocating EM air pump. The effects of various operating parameters on the EM air pump were investigated with the root-mean-square (RMS) flow rate and current. A core with a higher relative permeability shows better performance. The RMS current linearly increases with the applied voltage and shows no dependence on the frequency. The RMS flow rate also increases with the voltage. The RMS flow rate per power consumption is highest at the frequency around 20 Hz and decreases as the applied voltage increases. When the reciprocating EM air pump was used to supply air to the portable PEMFC, it was found that the power density of the PEMFC increases with the applied voltage and shows the highest performance at the frequency of 10 Hz. We compared the performance of the PEMFC between the flow meter and the EM air pump used as an air supplier. About 81% of the output power using the flow meter was obtained when the EM air pump is operated at the applied voltage of 5 V. The parasitic power ratio reaches at its minimum value about 0.1 with an EM applied voltage of 0.25V. (paper)

  11. Clean Air and Water

    Centers for Disease Control (CDC) Podcasts

    2007-04-10

    The air we breathe and the water we drink are both vital components of our health. Nevertheless, bacteria, pollutants, and other contaminates can alter life-giving air and water into health-threatening hazards. Learn about how scientists at the Centers for Disease Control and Prevention work to protect the public from air and water-related health risks.  Created: 4/10/2007 by CDC National Center for Environmental Health.   Date Released: 4/13/2007.

  12. AIR / SEA RESCUE LAUNCHES

    Directory of Open Access Journals (Sweden)

    W.H. Rice

    2012-02-01

    Full Text Available The Motor Boat Wing of the South African Air Force was inaugurated some thirty eight years ago.With its main base at Gordon's Bay, the wing was formed to operate the various marine craft used to provide a service to the flying component of the South African Air Force. Its main function was to be air/sea rescue, but it also had to man and maintain armoured target boats, seaplane tenders, marine tenders and the 'bomb scows', used for recovering practise bombs and missiles and for laying and lifting moorings.

  13. Mid-air Acrobatics

    Institute of Scientific and Technical Information of China (English)

    LlU FENG'AN

    2011-01-01

    On September 1 two new aerobatic demonstration teams,theSky Wing and the Red Falcon,debuted at an air show held in Changchun,capital of northeast China's Jilin Province.The show was staged at a ceremony held by the Aviation University of the People's Liberation Army (PLA) Air Force.Also performing at the show was the 50-year-old Bayi aerobatic demonstration team.The teams demonstrated their superlative flying skills,which showcase the quality of the air force's rigorous pilot training.

  14. Air/liquid collectors

    DEFF Research Database (Denmark)

    Jensen, Søren Østergaard; Olesen, Ole; Kristiansen, Finn Harken

    1997-01-01

    This report determine efficiency equations for combined air/liquid solar collectors by measurements on to different air/liquid collectors. Equations which contain all relevant informations on the solar collectors. A simulation program (Kviksol) has been modified in order to be able to handle this...... kind of collectors. The modified simulation program has been used for the determination of the surplus in performance which solar heating systems with this type of solar collectors for combined preheating of ventilation air and domestic hot water will have. The simulation program and the efficiency...

  15. Air Quality Monitoring Programme

    DEFF Research Database (Denmark)

    Kemp, K.; Palmgren, F.

    The air quality in Danish cities has been monitored continuously since 1982 within the Danish Air Quality (LMP) network. The aim has been to follow the concentration levels of toxic pollutants in the urban atmosphere and to provide the necessary knowledge to assess the trends, to perform source...... apportionment, and to evaluate the chemical reactions and the dispersion of the pollutants in the atmosphere. In 2002 the air quality was measured in four Danish cities and at two background sites. NO2 and PM10 were at several stations found in concentrations above the new EU limit values, which the Member...

  16. Olefin metathesis in air

    Directory of Open Access Journals (Sweden)

    Lorenzo Piola

    2015-10-01

    Full Text Available Since the discovery and now widespread use of olefin metathesis, the evolution of metathesis catalysts towards air stability has become an area of significant interest. In this fascinating area of study, beginning with early systems making use of high oxidation state early transition metal centers that required strict exclusion of water and air, advances have been made to render catalysts more stable and yet more functional group tolerant. This review summarizes the major developments concerning catalytic systems directed towards water and air tolerance.

  17. Air issues update

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    A government sponsored poll revealed that the primary environmental concern for Ontarians in 2000 was air pollution. While scientists tend to focus on smog episodes, greenhouse gas emissions, acid rain or emissions of toxic pollutants, the public shows concern in more practical terms such as the overall impact of poor air quality on people and the ecosystem, and how this will affect future life on earth. It was emphasized that policy makers should try to apply this holistic approach to the complex issues associated with air quality. Climate change, acid rain and ultraviolet radiation are some examples of how air emissions impact on ecosystems. Other examples include elevated levels of mercury in otters in Ontario. Climate change has also been linked with the re-acidification of lakes, as droughts typically occur in years following an El Nino cycle which has been pronounced as a possible consequence of greenhouse gas emissions. The Environmental Commissioner of Ontario (ECO) has reviewed the efforts of the Ontario Ministry of the Environment (MOE) regarding the regulation of air quality. The MOE has proposed several initiatives, including newer air dispersion models into legislation, establishing a new consultation process for applying new air quality standards to emission sources, an expansion of the Drive Clean Program, and a discussion paper on a proposed emission cap and trade system. This paper presents ECO's review of these initiatives and provides updates on other air quality issues such as control of emissions from Ontario's transportation, industrial and electricity sectors. It also described policy proposals related to standard-setting for air pollutants, as well as the newly adopted Canada-wide Standards for Particulate Matter and Ozone. A progress report on Ontario's Anti-Smog Action Plan (ASAP) confirms that major reductions in NO{sub x} expected from Ontario's coal-fired power plants never materialized. Emissions of nitrogen oxide

  18. Training Studies with Compressed Air Breathing Apparatus – Methodology, Exercises

    Directory of Open Access Journals (Sweden)

    Buks Roberts

    2015-11-01

    Full Text Available The current article describes topics ranging from the respiratory physiology and the structure of compressed air breathing apparatus to the performance of practical training exercises in an unbreathable environment (hereinafter referred to as UE.

  19. Current lead thermal analysis code 'CURRENT'

    International Nuclear Information System (INIS)

    Large gas-cooled current lead with the capacity more than 30 kA and 22 kV is required for superconducting toroidal and poloidal coils for fusion application. The current lead is used to carry electrical current from the power supply system at room temperature to the superconducting coil at 4 K. Accordingly, the thermal performance of the current lead is significantly important to determine the heat load requirements of the coil system at 4 K. Japan Atomic Energy Research Institute (JAERI) has being developed the large gas-cooled current leads with the optimum condition in which the heat load is around 1 W per 1 kA at 4 K. In order to design the current lead with the optimum thermal performances, JAERI developed thermal analysis code named as ''CURRENT'' which can theoretically calculate the optimum geometric shape and cooling conditions of the current lead. The basic equations and the instruction manual of the analysis code are described in this report. (author)

  20. Emission Facilities - Air Emission Plants

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Represents the Primary Facility type Air Emission Plant (AEP) point features. Air Emissions Plant is a DEP primary facility type related to the Air Quality Program....

  1. Introduction to Indoor Air Quality

    Science.gov (United States)

    ... US Environmental Protection Agency Search Search Indoor Air Quality (IAQ) Share Facebook Twitter Google+ Pinterest Contact Us ... Indoor Air Quality An Introduction to Indoor Air Quality IAQ & Health Causes of IAQ Problems Identifying IAQ ...

  2. Air transportation energy efficiency

    Science.gov (United States)

    Williams, L. J.

    1977-01-01

    The energy efficiency of air transportation, results of the recently completed RECAT studies on improvement alternatives, and the NASA Aircraft Energy Efficiency Research Program to develop the technology for significant improvements in future aircraft were reviewed.

  3. Criteria Air Emissions Trends

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Air Emissions Trends site provides national trends of criteria pollutant and precursor emissions data based on the the National Emissions Inventory (NEI) from...

  4. Indoor air quality

    International Nuclear Information System (INIS)

    Indoor Air Quality is rapidly becoming a major environmental concern because a significant amount of people spend a substantial amount of time in a variety of different indoor environments. Health effects from indoor pollutants fall into two categories: those that are experienced immediately after exposure and those that do not show up until years later. They are: radon, formaldehyde, asbestos, lead and household organic chemicals. The authors presented a source-by-source look at the most common indoor air pollutants, their potential health effects, and ways to reduce their levels in the home. There are three basic strategies to improve indoor air quality: one method is source control, another is through ventilation improvements, and the third is the utilization of some sort of mechanical device such as air cleaners

  5. Transportation and Air Quality

    Science.gov (United States)

    ... factors research. - Modeling & Inventories - Testing & Measuring Emissions - Clean Automotive Technologies - Emission Factors Research This page is maintained by EPA's Office of Transportation and Air Quality (OTAQ) . For more: About Us | Get E-mail ...

  6. Air conditioning system

    Science.gov (United States)

    Lowenstein, Andrew; Miller, Jeffrey; Gruendeman, Peter; DaSilva, Michael

    2005-02-01

    An air conditioner comprises a plurality of plates arranged in a successively stacked configuration with portions thereof having a spaced apart arrangement, and defining between successive adjacent pairs of plates at the spaced apart portions a first and second series of discrete alternating passages wherein a first air stream is passed through the first series of passages and a second air stream is passed through the second series of passages; and said stacked configuration of plates forming integrally therewith a liquid delivery means for delivering from a source a sufficient quantity of a liquid to the inside surfaces of the first series of fluid passages in a manner which provides a continuous flow of the liquid from a first end to a second end of the plurality of plates while in contact with the first air stream.

  7. Indoor air pollution

    International Nuclear Information System (INIS)

    Although official efforts to control air pollution have traditionally focused on outdoor air, it is now apparent that elevated contaminant concentrations are common inside some private and public buildings. Concerns about potential public health problems due to indoor air pollution are based on evidence that urban residents typically spend more than 90 percent of their time indoors, concentrations of some contaminants are higher indoors than outdoors, and for some pollutants personal exposures are not characterized adequately by outdoor measurements. Among the more important indoor contaminants associated with health or irritation effects are passive tobacco smoke, radon decay products, carbon monoxide, nitrogen dioxide, formaldehyde, asbestos fibers, microorganisms and aeroallergens. Efforts to assess health risks associated with indoor air pollution are limited by insufficient information about the number of people exposed, the pattern and severity of exposures, and the health consequences of exposures. An overall strategy should be developed to investigate indoor exposures, health effects, control options, and public policy alternatives

  8. Indoor air quality

    International Nuclear Information System (INIS)

    Rising energy prices, among other factors, have generated an incentive to reduce ventilation rates and thereby reduce the cost of heating and cooling buildings. Reduced ventilation in buildings may significantly increase exposure to indoor air pollution and perhaps have adverse effects on occupant health and comfort. Preliminary findings suggest that reduced ventilation may adversely affect indoor air quality unless appropriate control strategies are undertaken. The strategies used to control indoor air pollution depend on the specific pollutant or class of pollutants encountered, and differ somewhat depending on whether the application is to an existing building or a new building under design and construction. Whenever possible, the first course of action is prevention or reduction of pollutant emissions at the source. In most buildings, control measures involve a combination of prevention, removal, and suppression. Common sources of indoor air pollution in buildings, the specific pollutants emitted by each source, the potential health effects, and possible control techniques are discussed

  9. Radioactive air sampling methods

    CERN Document Server

    Maiello, Mark L

    2010-01-01

    Although the field of radioactive air sampling has matured and evolved over decades, it has lacked a single resource that assimilates technical and background information on its many facets. Edited by experts and with contributions from top practitioners and researchers, Radioactive Air Sampling Methods provides authoritative guidance on measuring airborne radioactivity from industrial, research, and nuclear power operations, as well as naturally occuring radioactivity in the environment. Designed for industrial hygienists, air quality experts, and heath physicists, the book delves into the applied research advancing and transforming practice with improvements to measurement equipment, human dose modeling of inhaled radioactivity, and radiation safety regulations. To present a wide picture of the field, it covers the international and national standards that guide the quality of air sampling measurements and equipment. It discusses emergency response issues, including radioactive fallout and the assets used ...

  10. Regional Air Quality Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset provides data on regional air quality, including trace level SO2, nitric acid, ozone, carbon monoxide, and NOy; and particulate sulfate, nitrate, and...

  11. Air Data Calibration Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This facility is for low altitude subsonic altimeter system calibrations of air vehicles. Mission is a direct support of the AFFTC mission. Postflight data merge is...

  12. Current measurement apparatus

    Science.gov (United States)

    Umans, Stephen D.

    2008-11-11

    Apparatus and methods are provided for a system for measurement of a current in a conductor such that the conductor current may be momentarily directed to a current measurement element in order to maintain proper current without significantly increasing an amount of power dissipation attributable to the current measurement element or adding resistance to assist in current measurement. The apparatus and methods described herein are useful in superconducting circuits where it is necessary to monitor current carried by the superconducting elements while minimizing the effects of power dissipation attributable to the current measurement element.

  13. INDOOR AIR QUALITY ANALYSIS

    OpenAIRE

    Wang, Xin

    2010-01-01

    With the development of modern architecture, one of the building's interior decoration, furnishings, appliances and equipment have become increasingly demanding, making construction of the indoor environment of increasing pollution, increasing pollution, indoor environmental pollution hazards to human is also a growing the greater. This thesis summarizes the major indoor air pollution sources and major pollutants. Indoor air pollutants are formaldehyde, radon, ammonia, total volatile org...

  14. Indoor Air Pollution

    OpenAIRE

    Kirk R Smith

    2003-01-01

    Outdoor air pollution in developing-country cities is difficult to overlook. Indoor air pollution caused by burning such traditional fuels as wood, crop residues, and dung is less evident, yet it is responsible for a significant part of country and global disease burdens. The main groups affected are poor women and children in rural areas and urban slums as they go about their daily activi...

  15. INDOOR AIR POLLUTION

    OpenAIRE

    Ahmet Soysal; Yucel Demiral

    2007-01-01

    The existance of hazardious materials including biological, chemical, and physical agents such as carbon dioxide, carbon monoxide, sulphur dioxide, nitrogen oxides, radon, volotile organic compounds, microorganisms in houses and the other non-industrilized buildings have been defined as “indoor air pollution”. Indoor air pollutants could possible arised from inside or outside environment and categorized into six subgroups. Almost 80% Turkish population have living in the urban areas...

  16. Air Distribution in Rooms

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    The research on air distribution in rooms is often done as full-size investigations, scale-model investigations or by Computational Fluid Dynamics (CFD). New activities have taken place within all three areas and this paper draws comparisons between the different methods. The outcome of the l......EA sponsored research "Air Flow Pattern within Buildings" is used for comparisons in some parts of the paper because various types of experiments and many countries are involved....

  17. Hot Air Engines

    OpenAIRE

    P. Stouffs

    2011-01-01

    Invented in 1816, the hot-air engines have known significant commercial success in the nineteenth century, before falling into disuse. Nowadays they enjoy a renewed interest for some specific applications. The "hot-air engines" family is made up of two groups: Stirling engines and Ericsson engines. The operating principle of Stirling and Ericsson engines, their troubled history, their advantages and their niche applications are briefly presented, especially in the field of...

  18. Air gun test facility

    International Nuclear Information System (INIS)

    This paper describes a facility that is potentially useful in providing data for models to predict the effects of nuclear explosions on cities. IIT Research Institute has a large air gun facility capable of launching heavy items of a wide variety of geometries to velocities ranging from about 80 fps to 1100 fps. The facility and its capabilities are described, and city model problem areas capable of investigation using the air gun are presented

  19. Canada's Clean Air Act

    International Nuclear Information System (INIS)

    This paper provided an outline of Canada's Clean Air Act and examined some of the regulatory changes that will occur as a result of its implementation. The Act is being introduced to strengthen the legislative basis for taking action on reducing air pollution and GHGs, and will allow the government to regulate both indoor and outdoor air pollutants and GHGs. The Act will require the Ministers of the Environment and Health to establish national air quality objectives, as well as to monitor and report on their attainment. The Canadian Environmental Protection Act will be amended to enable the government to regulate the blending of fuels and their components. The Motor Vehicle Fuel Consumption Standards Act will also be amended to enhance the government's authority to regulate vehicle fuel efficiency. The Energy Efficiency Act will also be expanded to allow the government to set energy efficiency standards and labelling requirements for a wider range of consumer and commercial products. The Act will commit to short, medium and long-term industrial air pollution targets. Regulations will be proposed for emissions from industry; on-road and off-road vehicles and engines; and consumer and commercial products. It was concluded that the Government of Canada will continue to consult with provinces, territories, industries and Canadians to set and reach targets for the reduction of both indoor and outdoor air pollutants and GHG emissions. 6 figs

  20. Air Force Research Laboratory Cryocooler Technology Development

    Science.gov (United States)

    Davis, Thomas M.; Smith, D. Adam; Easton, Ryan M.

    2004-06-01

    This paper presents an overview of the cryogenic refrigerator and cryogenic integration programs in development and characterization under the Cryogenic Cooling Technology Group, Space Vehicles Directorate of the Air Force Research Laboratory (AFRL). The vision statement for the group is to support the space community as the center of excellence for developing and transitioning space cryogenic thermal management technologies. This paper will describe the range of Stirling, pulse tube; reverse Brayton, and Joule-Thomson cycle cryocoolers currently under development to meet current and future Air Force and Department of Defense requirements. Cooling requirements at 10K, 35K, 60K, 95K, and multistage cooling requirements at 35/85K are addressed. In order to meet these various requirements, the Air Force Research Laboratory, Space Vehicles Directorate is pursuing various strategic cryocooler and cryogenic integration options. The Air Force Research Laboratory, working with industry partners, is also developing several advanced cryogenic integration technologies that will result in the reduction in current cryogenic system integration penalties and design time. These technologies include the continued development of gimbaled transport systems, 35K and 10K thermal storage units, heat pipes, cryogenic straps, and thermal switches.

  1. Coherent radiation from extensive air showers

    International Nuclear Information System (INIS)

    The generic properties of the emission of coherent radiation from a moving charge distribution are discussed. The general structure of the charge and current distributions in an extensive air shower are derived. These are subsequently used to develop a very intuitive picture for the properties of the emitted radio pulse. Using this picture can be seen that the structure of the pulse is a direct reflection of the shower profile. At higher frequencies the emission is suppressed because the wavelength is shorter than the important length scale in the shower. It is shown that radio emission can be used to distinguish proton- and iron-induced air showers.

  2. ACS air bearing test-bed design

    OpenAIRE

    Glitt, Sascha

    2010-01-01

    This thesis is about the construction and design of a new air bearing test-bed to verify the programmed ACS attitude control algorithm and to validate the ACS MATLAB/SimuLink¬ model of NPSAT1, the second small satellite currently under development at the Naval Postgraduate School Space Systems Academic Group. The software was already verified and validated using a comparable air bearing test-bed. But due to changes in hardware from commercial magnetic torque rods to custom, NPS-built, magneti...

  3. Biomass and air quality the UK experience

    International Nuclear Information System (INIS)

    Policies to encourage the use of biomass in the UK can perhaps be held up as an example of how not to develop integrated environmental policy. The UK has considered the air quality effects of biomass burning only after putting in place policies that will hugely increase the amount of biomass burning plant that will be installed. Whilst these issues are now being addressed, it will be some time before a satisfactory framework will be in place. The current situation is not a positive one for all involved - air quality practitioners, climate change policy makers and the wider biomass industry. For clean air organisations such as Environmental Protection UK and our European counterparts there are essentially two lessons to take away. The first is that we have to raise our sights to look for potential threats to air quality from wider policy measures, and flag up potential concerns at the earliest opportunity. It is easy to focus on the job in hand (for example emissions from vehicles) and miss developments further afield. Secondly, and most importantly, we have to offer our own solutions to wider environmental challenges. Climate change is likely to remain the dominant global environmental issue for decades to come; clean air agencies need to understand this and put forward low carbon solutions that offer strong synergies with air quality. The alternative is for policy makers to see air i quality standards and clean air agencies as a barrier t to progress towards a low carbon economy, rather than a positive source of solutions. (N.C.)

  4. Hanford Site air operating permit application

    International Nuclear Information System (INIS)

    The Clean Air Act Amendments of 1990, which amended the Federal Clean Air Act of 1977, required that the US Environmental Protection Agency develop a national Air Operating Permit Program, which in turn would require each state to develop an Air Operating Permit Program to identify all sources of ''regulated'' pollutants. Regulated pollutants include ''criteria'' pollutants (oxides of nitrogen, sulfur oxides, total suspended particulates, carbon monoxide, particulate matter greater than 10 micron, lead) plus 189 other ''Hazardous'' Air Pollutants. The Hanford Site, owned by the US Government and operated by the US Department of Energy, Richland Operations Office, is located in southcentral Washington State and covers 560 square miles of semi-arid shrub and grasslands located just north of the confluence of the Snake and Yakima Rivers with the Columbia River. This land, with restricted public access, provides a buffer for the smaller areas historically used for the production of nuclear materials, waste storage, and waste disposal. About 6 percent of the land area has been disturbed and is actively used. The Hanford Site Air Operating Permit Application consists of more than 1,100 sources and in excess of 300 emission points. Before January 1995, the maintenance and operations contractor and the environmental restoration contractor for the US Department of Energy completed an air emission inventory on the Hanford Site. The inventory has been entered into a database so that the sources and emission points can be tracked and updated information readily can be retrieved. The Hanford Site Air Operating Permit Application contains information current as of April 19, 1995

  5. Hanford Site air operating permit application

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    The Clean Air Act Amendments of 1990, which amended the Federal Clean Air Act of 1977, required that the US Environmental Protection Agency develop a national Air Operating Permit Program, which in turn would require each state to develop an Air Operating Permit Program to identify all sources of ``regulated`` pollutants. Regulated pollutants include ``criteria`` pollutants (oxides of nitrogen, sulfur oxides, total suspended particulates, carbon monoxide, particulate matter greater than 10 micron, lead) plus 189 other ``Hazardous`` Air Pollutants. The Hanford Site, owned by the US Government and operated by the US Department of Energy, Richland Operations Office, is located in southcentral Washington State and covers 560 square miles of semi-arid shrub and grasslands located just north of the confluence of the Snake and Yakima Rivers with the Columbia River. This land, with restricted public access, provides a buffer for the smaller areas historically used for the production of nuclear materials, waste storage, and waste disposal. About 6 percent of the land area has been disturbed and is actively used. The Hanford Site Air Operating Permit Application consists of more than 1,100 sources and in excess of 300 emission points. Before January 1995, the maintenance and operations contractor and the environmental restoration contractor for the US Department of Energy completed an air emission inventory on the Hanford Site. The inventory has been entered into a database so that the sources and emission points can be tracked and updated information readily can be retrieved. The Hanford Site Air Operating Permit Application contains information current as of April 19, 1995.

  6. Generation of subnanosecond electron beams in air at atmospheric pressure

    Science.gov (United States)

    Kostyrya, I. D.; Tarasenko, V. F.; Baksht, E. Kh.; Burachenko, A. G.; Lomaev, M. I.; Rybka, D. V.

    2009-11-01

    Optimum conditions for the generation of runaway electron beams with maximum current amplitudes and densities in nanosecond pulsed discharges in air at atmospheric pressure are determined. A supershort avalanche electron beam (SAEB) with a current amplitude of ˜30 A, a current density of ˜20 A/cm2, and a pulse full width at half maximum (FWHM) of ˜100 ps has been observed behind the output foil of an air-filled diode. It is shown that the position of the SAEB current maximum relative to the voltage pulse front exhibits a time shift that varies when the small-size collector is moved over the foil surface.

  7. Clean air Hamilton

    Energy Technology Data Exchange (ETDEWEB)

    McCarry, B.E. [McMaster Univ., Hamilton, ON (Canada)

    2002-07-01

    The industrial City of Hamilton is located on Lake Ontario, downwind from the Ohio Valley. The Hamilton Air Quality Initiative (HAQI) was divided in several phases, one of which is Clean Air Hamilton. This most recent phase was described in this presentation. Two major goals of this phase were: to ensure that the City of Hamilton has the best air quality of any major urban area in Ontario, and to reduce the emissions of greenhouse gases by 20 per cent compared to the levels in 1990. There were five main objectives to this initiative, namely: (1) the identification of priority air quality issues, (2) achieving an understanding of air quality issues, (3) the identification of sources, the evaluation of impacts and the recommendation of solutions, (4) the assessment of human health, and (5) the identification of further research. The reduction of air quality impacts is progressing through the support provided to the Drive Clean Program, the discouragement of vehicle idling, the support to car pooling initiatives, and the promotion of green vehicles. The implementation of pollution control technologies is taking place on the industrial side, as well as the development of plans to reduce steel industry emissions, the development of energy conservation measures and the promotion of green building practices. Efforts are being deployed over fleet greening partnerships, community tree planting program, an international air conference, an electronic information network linking the United States and the communities of Southern Ontario, a road dust study, a truck emissions research project, the assessment of human health impacts, and finally methods for the monitoring of local improvements. figs.

  8. Current interruption transients calculation

    CERN Document Server

    Peelo, David F

    2014-01-01

    Provides an original, detailed and practical description of current interruption transients, origins, and the circuits involved, and how they can be calculated Current Interruption Transients Calculationis a comprehensive resource for the understanding, calculation and analysis of the transient recovery voltages (TRVs) and related re-ignition or re-striking transients associated with fault current interruption and the switching of inductive and capacitive load currents in circuits. This book provides an original, detailed and practical description of current interruption transients, origins,

  9. Marine Current Energy Conversion

    OpenAIRE

    Lundin, Staffan

    2016-01-01

    Marine currents, i.e. water currents in oceans and rivers, constitute a large renewable energy resource. This thesis presents research done on the subject of marine current energy conversion in a broad sense. A review of the tidal energy resource in Norway is presented, with the conclusion that tidal currents ought to be an interesting option for Norway in terms of renewable energy. The design of marine current energy conversion devices is studied. It is argued that turbine and generator cann...

  10. Recognizing the impact of ambient air pollution on skin health.

    Science.gov (United States)

    Mancebo, S E; Wang, S Q

    2015-12-01

    Ambient air pollution is a known public health hazard that negatively impacts non-cutaneous organs; however, our knowledge regarding the effects on skin remains limited. Current scientific evidence suggests there are four mechanisms by which ambient air pollutants cause adverse effects on skin health: (i) generation of free radicals, (ii) induction of inflammatory cascade and subsequent impairment of skin barrier, (iii) activation of the aryl hydrocarbon receptor (AhR) and (iv) alterations to skin microflora. In this review, we provide a comprehensive overview on ambient air pollutants and their relevant sources, and highlight current evidence of the effects on skin. PMID:26289769

  11. Steady Thermal Field Simulation of Forced Air-cooled Column-type Air-core Reactor

    Institute of Scientific and Technical Information of China (English)

    DENG Qiu; LI Zhenbiao; YIN Xiaogen; YUAN Zhao

    2013-01-01

    Modeling the steady thermal field of the column-type air-core reactor,and further analyzing its distribution regularity,will help optimizing reactor design as well as improving its quality.The operation mechanism and inner insulation structure of a novel current limiting column-type air-core reactor is introduced in this paper.The finite element model of five encapsulation forced air-cooled column type air-core reactor is constructed using Fluent.Most importantly,this paper present a new method that,the steady thermal field of reactor working under forced air-cooled condition is simulated without arbitrarily defining the convection heat transfer coefficient for the initial condition; The result of the thermal field distribution shows that,the maximum steady temperature rise of forced air-cooled columntype air-core reactor happens approximately 5% to its top.The law of temperature distribution indicates:In the 1/3part of the reactor to its bottom,the temperature will rise rapidly to the increasing of height,yet the gradient rate is gradually decreasing; In the 5 % part of the reactor to its top,the temperature will drop rapidly to the increasing of height; In the part between,the temperature will rise slowly to the increasing of height.The conclusion draws that more thermal withstand capacity should be considered at the 5 % part of the reactor to its top to achieve optimal design solution.

  12. Computers in Air Defence

    Directory of Open Access Journals (Sweden)

    P. V.S. Rao

    1987-10-01

    Full Text Available With man's mastery over the third dimension - the near atmosphere and space- it has become increasingly necessary to protect oneself not merely from attacks from land and the sea but, more importantly, from attacks from the air. This was recognised even during the World War II and a rudimentary air defence capability was sought to be established; by the manul (visual surveillance and the anti-aircraft guns. The advent of radar signified a major advance in air defence technology and techniques. Rather than depend on visual observation and the hazards and limitations thereof, it became possible with radar to detect the presence of flying objects at much great distances. The PPI display of a conventional air-surveillance radar permits an operator to scan the sky for several hundreds of kilometers all around. Early radar-based air defence systems were dependent on human observation and decision making for detecting targets, identifying them, deciding on interception strategy and for recovering the interceptor after completion of his mission. This was feasible because, with a radar of between 200 to 400 kilometers and aircraft speeds in the range of 500 kilometers per hour, upto 30 minutes warning was available before the target was overhead.

  13. Building ventilation and indoor air quality

    International Nuclear Information System (INIS)

    Rising energy prices, among other factors, have generated an incentive to reduce ventilation rates and thereby reduce the cost of heating and cooling buildings. Reduced infiltration and ventilation in buildings may significantly increase exposure to indoor contaminations and perhaps have adverse effects on occupant health and comfort. Four indoor air contaminants - carbon monoxide and nitrogen dioxide from gas appliances; formaldehyde from particleboard, plywood, urea-formaldehyde foam insulation, and gas appliances; and radon from building materials, soil, and ground water - are currently receiving considerable attention in the context of potential health risks associated with reduced infiltration and ventilation rates. The authors have measured and analyzed these air contaminants in conventional and energy efficient buildings with a view to assessing their potential health risks and various control strategies capable of lowering pollutant concentrations. Preliminary findings suggest that further intensive studies are needed in order to develop criteria for maintaining acceptable indoor air quality without compromising energy efficiency. (Auth.)

  14. Equivalence in Ventilation and Indoor Air Quality

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, Max; Walker, Iain; Logue, Jennifer

    2011-08-01

    We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy. To use variable ventilation in a way that meets standards, it is necessary to have a method for determining equivalence in terms of either ventilation or indoor air quality. This study develops methods to calculate either equivalent ventilation or equivalent IAQ. We demonstrate that equivalent ventilation can be used as the basis for dynamic ventilation control, reducing peak load and infiltration of outdoor contaminants. We also show that equivalent IAQ could allow some contaminants to exceed current standards if other contaminants are more stringently controlled.

  15. Helium corona-assisted air discharge

    Energy Technology Data Exchange (ETDEWEB)

    Jiang Nan; Gao Lei; Ji Ailing; Cao Zexian [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2011-10-15

    Operation of atmospheric discharge of electronegative gases including air at low voltages yet without consuming any inert gas will enormously promote the application of non-thermal plasmas. By taking advantage of the low onset voltage for helium corona, air discharge was successfully launched at much reduced voltages with a needle-plate system partly contained in a helium-filled glass bulb--for a needle-plate distance of 12 mm, 1.0 kV suffices. Ultraviolet emission from helium corona facilitates the discharging of air, and the discharge current manifests distinct features such as relatively broad Trichel pulses in both half periods. This design allows safe and economic implementation of atmospheric discharge of electronegative gases, which will find a broad palette of applications in surface modification, plasma medicine and gas treatment, etc.

  16. Helium corona-assisted air discharge

    International Nuclear Information System (INIS)

    Operation of atmospheric discharge of electronegative gases including air at low voltages yet without consuming any inert gas will enormously promote the application of non-thermal plasmas. By taking advantage of the low onset voltage for helium corona, air discharge was successfully launched at much reduced voltages with a needle-plate system partly contained in a helium-filled glass bulb--for a needle-plate distance of 12 mm, 1.0 kV suffices. Ultraviolet emission from helium corona facilitates the discharging of air, and the discharge current manifests distinct features such as relatively broad Trichel pulses in both half periods. This design allows safe and economic implementation of atmospheric discharge of electronegative gases, which will find a broad palette of applications in surface modification, plasma medicine and gas treatment, etc.

  17. Behaviour of air discharged from a sparger

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Yoon Yeong [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2000-03-01

    This research has been performed as a part of the project, Development of Design Verification Technology for Korea Next Generation Reactor. At first, current state of the art of the bubble dynamics and the result will be used to develop an optimum tool including computer code for analysis of air or air-steam mixture bubble, which is discharged from a sparger. Introduced are linear perturbation; spherical bubble cloud theory; bubble interaction; and Volume of Fluid, a method of tracking free surface, which is to be used in computational fluid dynamics. An analysis was performed for the oscillation of an air bubble of perfect spherical shape. The heat transfer through the bubble surface is considered, although the effect was not so significant. The effect of initial and boundary conditions were investigated and the correlation equation was developed. 42 refs., 22 figs., 2 tabs. (Author)

  18. Magnetodynamic waves in the air

    Science.gov (United States)

    Korolev, Alexander I.

    2013-02-01

    The paper describes experiments to search for a variable magnetic field close to a rechargeable conductive flat plate and a ball in the air, as well as an experiment looking for a variable electric field near a rotating permanent magnet. It has been found that variable electric and magnetic fields do not induce each other within the measurement error. It means that rotary Maxwell's equations are not applicable in the near-field zone and the classical concept of displacement current in vacuum (air) has no physical meaning. A conclusion is made on the existence of transverse magnetodynamic waves. Statics and dynamics of the magnetic field near the permanent magnet rod are investigated experimentally. The methods to compute magnetodynamic waves from any source are presented. Four types of polarization of these waves are identified: linear, circular, toroidal and mixed. Concentration and deflection of magnetodynamic waves are observed on introducing inhomogeneity in the form of a ferrite rod into their propagation way, which is similar to diffraction in optics. Secondary magnetodynamic waves from the induced magnetic moments in atoms of ferrite are registered near its surface, which is like reflection in optics. Some ideas for observation of effects similar to dispersion and interference are presented for magnetodynamic waves. The structure and properties of electrodynamic, magnetodynamic and electromagnetic waves are discussed. The ideas of experiments to search for their unknown properties are described. In conclusion, technical applications of magnetodynamic waves such as magnetography, magnetic tomography and other are considered.

  19. An Innovative Reactor Technology to Improve Indoor Air Quality

    Energy Technology Data Exchange (ETDEWEB)

    Rempel, Jane [TIAX LLC., Lexington, MA (United States)

    2013-03-30

    As residential buildings achieve tighter envelopes in order to minimize energy used for space heating and cooling, accumulation of indoor air pollutants such as volatile organic compounds (VOCs), becomes a major concern causing poor air quality and increased health risks. Current VOC removal methods include sorbents, ultraviolet photocatalytic oxidation (UVPCO), and increased ventilation, but these methods do not capture or destroy all VOCs or are prohibitively expensive to implement. TIAX's objective in this program was to develop a new VOC removal technology for residential buildings. This novel air purification technology is based on an innovative reactor and light source design along with UVPCO properties of the chosen catalyst to purify indoor air and enhance indoor air quality (IAQ). During the program we designed, fabricated and tested a prototype air purifier to demonstrate its feasibility and effectiveness. We also measured kinetics of VOC destruction on photocatalysts, providing deep insight into reactor design.

  20. Infants Can Study Air Science.

    Science.gov (United States)

    Ward, Alan

    1983-01-01

    Provided are activities and demonstrations which can be used to teach infants about the nature of air, uses of air, and objects that fly in the air. The latter include airships, hot-air balloons, kites, parachutes, airplanes, and Hovercraft. (JN)

  1. Selection of Air Terminal Device

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    This paper discusses the selection of the air terminal device for the experiments and numerical prediction in the International Energy Agency Annex 20 work: Air Flow Pattern within Buildings,......This paper discusses the selection of the air terminal device for the experiments and numerical prediction in the International Energy Agency Annex 20 work: Air Flow Pattern within Buildings,...

  2. Proceedings of the upwind downwind air quality conference 2004 : a practical conference on improving air quality

    International Nuclear Information System (INIS)

    This conference provided a forum for policy makers, environmental managers, urban designers and citizens to discuss current air quality issues. It provided information on urban sprawl and the resulting human health impacts. Many presentations described efforts that are currently underway to improve local air quality through smart growth initiatives, new urban design approaches, successful airshed management and planning legislation. The roles that industry, community groups and governments play in achieving air quality improvements were also highlighted. The mitigation efforts relate to both natural areas and industrial corridors and involve reducing waste, consuming less energy, changing our modes of transportation, and wise land use in urban areas. Sixteen presentations were indexed separately for inclusion in this database. refs., tabs., figs

  3. Circle Points Discharge Tube Current Controller

    Institute of Scientific and Technical Information of China (English)

    Meng Jinjia; Meng Lisheng

    2005-01-01

    Circle points discharge tube current controller is a new type device to limit theoutput of high voltage discharge current. Circle points uniform corona discharge to form airionization current in the discharge tube. On the outside, even if the discharge electrode is sparkdischarging or the two discharge electrodes are short circuited, the air ionization current in the tuberemains within a stable range, and there is no spark discharge. In this case, when the dischargecurrent only increases slightly, the requirement to limited current is obtained. By installing thecontroller at a discharge pole with a small power but high voltage supply, we can realize the shiftbetween the continuous spark line discharge and corona discharge. This provides a new simpledevice for spark discharge research and is a supplement to the Townsend discharge experiment.

  4. The Clean Air Act

    International Nuclear Information System (INIS)

    The Clean Air Act amendments alter the complex laws affecting atmospheric pollution and at the same time have broad implications for energy. Specifically, the Clean Air Act amendments for the first time deal with the environmental problem of acid deposition in a way that minimizes energy and economic impacts. By relying upon a market-based system of emission trading, a least cost solution will be used to reduce sulfur dioxide (SO2) emissions by almost 40 percent. The emission trading system is the centerpiece of the Clean Air Act (CAA) amendments effort to resolve energy and environmental interactions in a manner that will maximize environmental solutions while minimizing energy impacts. This paper will explore how the present CAA amendments deal with the emission trading system and the likely impact of the emission trading system and the CAA amendments upon the electric power industry

  5. Advanced Air Data Systems for Commercial Aircraft

    Science.gov (United States)

    2006-01-01

    It is possible to get a crude estimate of wind speed and direction while driving a car at night in the rain, with the motion of the raindrop reflections in the headlights providing clues about the wind. The clues are difficult to interpret, though, because of the relative motions of ground, car, air, and raindrops. More subtle interpretation is possible if the rain is replaced by fog, because the tiny droplets would follow the swirling currents of air around an illuminated object, like, for example, a walking pedestrian. Microscopic particles in the air (aerosols) are better for helping make assessments of the wind, and reflective air molecules are best of all, providing the most refined measurements. It takes a bright light to penetrate fog, so it is easy to understand how other factors, like replacing the headlights with the intensity of a searchlight, can be advantageous. This is the basic principle behind a lidar system. While a radar system transmits a pulse of radiofrequency energy and interprets the received reflections, a lidar system works in a similar fashion, substituting a near-optical laser pulse. The technique allows the measurement of relative positions and velocities between the transmitter and the air, which allows measurements of relative wind and of air temperature (because temperature is associated with high-frequency random motions on a molecular level). NASA, as well as the National Oceanic and Atmospheric Administration (NOAA), have interests in this advanced lidar technology, as much of their explorative research requires the ability to measure winds and turbulent regions within the atmosphere. Lidar also shows promise for providing warning of turbulent regions within the National Airspace System to allow commercial aircraft to avoid encounters with turbulence and thereby increase the safety of the traveling public. Both agencies currently employ lidar and optical sensing for a variety of weather-related research projects, such as analyzing

  6. Liquid air cycle engines

    Science.gov (United States)

    Rosevear, Jerry

    1992-01-01

    Given here is a definition of Liquid Air Cycle Engines (LACE) and existing relevant technologies. Heat exchanger design and fabrication techniques, the handling of liquid hydrogen to achieve the greatest heat sink capabilities, and air decontamination to prevent heat exchanger fouling are discussed. It was concluded that technology needs to be extended in the areas of design and fabrication of heat exchangers to improve reliability along with weight and volume reductions. Catalysts need to be improved so that conversion can be achieved with lower quantities and lower volumes. Packaging studies need to be investigated both analytically and experimentally. Recycling with slush hydrogen needs further evaluation with experimental testing.

  7. Unit for air decontamination

    International Nuclear Information System (INIS)

    To fulfill the applicable requirements of safety to the ventilation systems in nuclear facilities, it is necessary to make a cleaning of the air that hurtles to the atmosphere. For that which was designed and it manufactured an unit for decontamination of the air for the Pilot plant of production of Nuclear Fuel that this built one with national parts, uses Hepa national filters and the design can adapt for different dimensions of filters, also can be added a lodging for a prefilter or to adopt two Hepa filters. (Author)

  8. Air the excellent canopy

    CERN Document Server

    Fahy, F

    2013-01-01

    We take it for granted, but without it we perish and if we continue to abuse it, it may kill us in the end. This fascinating text provides an understanding and appreciation of the role that air plays in our environment and its importance in relation to human life and technology. Aimed at those who are scientifically curious but who have no specialist training, it contains no mathematical equations and relies upon the qualitative descriptions and analogies to explain the more technical parts of the text together with simple home experiments to illustrate a range of air-based phenomena. Liberall

  9. Air Freight and Logistics Services

    OpenAIRE

    Kiso, Fadila; Deljanin, Abidin

    2009-01-01

    Air transport industry has gradually increased its share of global passenger and freight traffic, and this trend has accelerated in the last 40 years. For the past decade, air-freight traffic growth has outpaced air passenger traffic growth by 1-2% each year. In the past, air-freight sector offered limited services, with heavy reliance on several intermediaries and a significant dependence on air passenger operations. The sector can now be characterized as a sophisticated, innovative one, rel...

  10. Primary and secondary consequences of indoor air cleaners.

    Science.gov (United States)

    Siegel, J A

    2016-02-01

    Air cleaning is broadly applied to reduce contaminant concentrations in many buildings. Although diverse in underlying technology, mode of application, target contaminants, and effectiveness, there are also commonalities in the framework for understanding their primary impact (i.e. concentration reductions) and secondary impacts (e.g. energy use and by-product production). Furthermore, both primary and secondary impacts are moderated by the specific indoor context in which an air cleaner is used. This investigation explores the dynamics of removal efficiency in a variety of air cleaners and combines efficiency and flow rate to put air cleaning in the context of real indoor environments. This allows for the direct comparison to other indoor pollutant loss mechanisms (ventilation and deposition) and further suggests that effective air cleaner use is context and contaminant specific. The concentration reduction impacts of air cleaning need to be contrasted with the secondary consequences that arise from the use of air cleaners. This study emphasizes two important secondary consequences: energy use of the air cleaning process and primary and secondary emissions from air cleaners. This study also identifies current research challenges and areas for large leaps in our understanding of the role of air cleaners in improving indoor environmental quality. PMID:25689321

  11. Current Research Studies

    Science.gov (United States)

    ... Home > Explore CCFA Research > Current Research Studies Current Research Studies Email Print + Share The Crohn’s & Colitis Foundation ... online. Learn more about CCFA Partners. CCFA Clinical Research Alliance The Clinical Research Alliance is a network ...

  12. 33 CFR 334.1280 - Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force. 334.1280 Section 334.1280 Navigation and Navigable... REGULATIONS § 334.1280 Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force....

  13. Pollution prevention at ports: clearing the air

    International Nuclear Information System (INIS)

    Seaports are major hubs of economic activity and of environmental pollution in coastal urban areas. Due to increasing global trade, transport of goods through ports has been steadily increasing and will likely continue to increase in the future. Evaluating air pollution impacts of ports requires consideration of numerous sources, including marine vessels, trucks, locomotives, and off-road equipment used for moving cargo. The air quality impacts of ports are significant, with particularly large emissions of diesel exhaust, particulate matter, and nitrogen oxides. The health effects of these air pollutants to residents of local communities include asthma, other respiratory diseases, cardiovascular disease, lung cancer, and premature mortality. In children, there are links with asthma, bronchitis, missed school days, and emergency room visits. The significance of these environmental health impacts requires aggressive efforts to mitigate the problem. Approaches to mitigation encompass a range of possibilities from currently available, low-cost approaches, to more significant investments for cleaner air. Examples of the former include restrictions on truck idling and the use of low-sulfur diesel fuel; the latter includes shore-side power for docked ships, and alternative fuels. A precautionary approach to port-related air pollution would encourage local production of goods in order to reduce marine traffic, greener design for new terminals, and state-of-the art approaches to emissions-control that have been successfully demonstrated at ports throughout the world

  14. Eddy current seminar

    International Nuclear Information System (INIS)

    The paper presents the fifth symposium in the series of Eddy Current Seminars, held in Abingdon, 1988. The meeting included a discussion on three-dimensional eddy current formulations, as well as thirteen contributed papers on computational electromagnetics. Of the thirteen papers, two papers on eddy currents in tokamaks were selected for INIS and indexed separately. (U.K.)

  15. Indoor air pollution

    International Nuclear Information System (INIS)

    Indoor air pollution is a potential risk to human health. Prolonged exposure to indoor pollutants may cause various infectious, allergic and other diseases. Indoor pollutants can emanate from a broad array of internal and external sources. Internal sources include building and furnishing materials, consumer and commercial products, office equipment, micro-organisms, pesticides and human occupants activities. External sources include soil, water supplies and outside makeup air. The main indoor air pollutants of concern are inorganic gases, formaldehyde and other volatile organic compounds, pesticides, radon and its daughters, particulates and microbes. The magnitude of human exposure to indoor pollutants can be estimated or predicted with the help of mathematical models which have been developed using the data from source emission testing and field monitoring of pollutants. In order to minimize human exposure to indoor pollutants, many countries have formulated guidelines / standards for the maximum permissible levels of main pollutants. Acceptable indoor air quality can be achieved by controlling indoor pollution sources and by effective ventilation system for removal of indoor pollutants. (author)

  16. Indoor air quality research

    International Nuclear Information System (INIS)

    The various types of pollutant found in indoor air are introduced and the effects on the health of the occupants of buildings summarized. The ''sick'' building syndrome is described in detail and the need for further investigation into its causes and remedies is stressed. 8 tabs

  17. Mid-air Acrobatics

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Two new aerobatic demonstration teams take to the skies On September 1,two new aerobatic demonstration teams,the Sky Wing and the Red Falcon,debuted at an air show held in Changchun,capital of northeast China’s Jilin Province.

  18. Russia air management program

    Energy Technology Data Exchange (ETDEWEB)

    Pace, T.G. [U.S. Environmental Protection Agency, NC (United States); Markin, S. [Ministry of Environmental Protection and Natural Resources, Moscow (Sweden); Kosenkova, S.V. [Volgograd Environmental Services Administration, Volgograd (Russian Federation)

    1995-12-31

    The Russia Air Management Program is in the second year of a four-year cooperative program between the Russian Ministry of Environmental Protection and Natural Resources (MEPNR) and the U.S. Environmental Protection Agency (EPA) to improve national institutions, policies, and practices for air quality management in Russia. This program is part of the Environmental Policy and Technology project being conducted by the U.S. Agency for International Development. The Russia Air Management Program will pilot the application of potential air program improvements in the important industrial City of Volgograd which will enable the development, practical demonstration and evaluation of alternative approaches for improving AQM policies and practices in Russia. Volgograd has a progressive and environmentally enlightened local government, a diverse industrial base and a relatively healthy economy. It is located south of Moscow on the Volga River and was proposed by the Ministry of Environmental Protection and Natural Resources. It was selected after a site visit and a series of discussions with the Ministry, Volgograd officials, the World Bank and the EPA. Following the pilot, RAMP will work to facilitate implementation of selected parts of the pilot in other areas of Russia using training, technology transfer, and public awareness. (author)

  19. Air Quality Monitoring Programme

    DEFF Research Database (Denmark)

    Kemp, K.; Palmgren, F.

    The Danish Air Quality Monitoring Programme (LMP IV) has been revised in accordance with the Framework Directive and the first three daughter directives of SO2, NOx/NO2, PM10, lead, benzene, CO and ozone. PM10 samplers are under installation and the installation will be completed during 2002...

  20. Indoor Air Quality

    DEFF Research Database (Denmark)

    Selman, Ayser Dawod; Heiselberg, Per

    Overall purpose of the research is to provide an overview of the relevance and importance of various defined Indoor Air Quality (IAQ) parameters in a European perspective. Based on the report it should be possible to prioritize which countries to target for further activities as well as it should...

  1. Hexane Air Combustion

    CERN Document Server

    Boettcher, Philipp A; Shepherd, Joseph E

    2010-01-01

    Hot surface ignition and subsequent flame propagation of premixed n-hexane air mixtures are shown in this fluid dynamics video. High speed schlieren photography revealed 3 distinct behaviors of ignition and propagation as a function of mixture composition and initial pressure.

  2. Images in the Air

    Science.gov (United States)

    Riveros, H. G.; Rosenberger, Franz

    2012-01-01

    This article discusses two "magic tricks" in terms of underlying optical principles. The first trick is new and produces a "ghost" in the air, and the second is the classical real image produced with two parabolic mirrors. (Contains 2 figure and 6 photos.)

  3. Ames Air Revitalization

    Science.gov (United States)

    Huang, Roger Z.

    2015-01-01

    This is an informal presentation presented to the University of Colorado, Boulder Bioastronautics group seminar. It highlights the key focal areas of the Air Revitalization Group research over the past year, including progress on the CO2 Removal and Compression System, testing of CDRA drying bed configurations, and adsorption research.

  4. Hydrogen-air detonations

    International Nuclear Information System (INIS)

    General gaseous detonation propagation phenomena are briefly discussed. The importance of cellular structure and cell size to detonation initiation, transmission and failure is emphasized. Experimental measurements of cell size lambda for hydrogen-air-carbon dioxide mixtures are presented; the hydrogen/air volume ratios range between 0.16 and 1.5 and the carbon dioxide mole fractions are 0, 0.05, 0.10 and 0.15. Cell sizes are a minimum for both diluted and undiluted hydrogen-air mixtures near stoichiometric (i.e., hydrogen/air = 0.4). Minimum cell sizes for carbon dioxide mole fractions of 0, 0.05, 0.10 and 0.15 are 1.51, 2.05, 4.2 and 15.0 cm, respectively. Results of large- and small-scale critical tube diameter (d/sub c/) measurements are presented and show good agreement with the empirical scaling law, d/sub c/ = 13 lambda. Mean detonation velocities and pressures have been measured and compared to the theoretical Chapman-Jouguet values

  5. Air-cleaning apparatus

    International Nuclear Information System (INIS)

    An air-cleaning, heat-exchange apparatus includes a main housing portion connected by means of an air inlet fan to the kitchen exhaust stack of a restaurant. The apparatus includes a plurality of heat exchangers through which a heat-absorptive fluid is circulated, simultaneously, by means of a suitable fluid pump. These heat exchangers absorb heat from the hot exhaust gas, out of the exhaust stack of the restaurant, which flows over and through these heat exchangers and transfers this heat to the circulating fluid which communicates with remote heat exchangers. These remote heat exchangers further transfer this heat to a stream of air, such as that from a cold-air return duct for supplementing the conventional heating system of the restaurant. Due to the fact that such hot exhaust gas is heavily grease laden , grease will be deposited on virtually all internal surfaces of the apparatus which this exhaust gas contacts. Consequently, means are provided for spraying these contacted internal surfaces , as well as the hot exhaust gas itself, with a detergent solution in which the grease is soluble, thereby removing grease buildup from these internal surfaces

  6. Learning AirWatch

    CERN Document Server

    Dunkerley, Mark

    2015-01-01

    If you are a technical professional who wants to dive deeper into the functionality offered by AirWatch or manage the solution, then this book will help you choose the best set of configuration, device management, and monitoring options that you can use to effectively manage your EMM implementation.

  7. Air quality indicators

    International Nuclear Information System (INIS)

    This report proposes and describes in detail several air quality indicators that may be used to describe population exposure. The suggested indicators account for temporal and spatial patterns of pollution and movements of individuals between different micro-environments. The Air Quality Indicator /AQI) should represent both the spatial and temporal aspects of pollution exposure that may have important effects on health. Two indicators are needed, the Population Air Quality Indicator and the Individual Air Quality Indicator. Mean concentrations, 98th percentile and maximum values are the traditional indicators for estimating exposure. the temporal variability of PM-10 and NO2, however, is here described by means of: 1) The rate of change of pollution as the difference between two consecutive hourly values and of 2) episodes, described in terms of number, duration and winter episode period, maximum concentration in the episode and integrated episode exposure (episode AOT50/100). The spatial variation of AQIs can be described in several ways, e.g.: 1) Concentrations in neighbouring grid squares can be compared as an indication of spatial variation and 2) point estimates can be compared to grid values for a description of variation within a grid. Both methods are presented here. A test of the representativity of static point estimates for pollution exposure is to compare them to an estimate of air pollution exposure accounting for movements between different locations, obtained using diaries. The ultimate aim of AQIs is to describe the population exposure to ambient pollution. This is done by estimating the number of people exposed using different characteristics of AQIs. The data used to describe these indicators originates from dispersion modelling of short-term air pollution concentrations in Oslo. Two series of data are used. One represents hour-for hour concentrations in the 1 km2 grid system covering the city of Oslo, winter 1994/95, calculated by the grid

  8. Current enhancement update

    International Nuclear Information System (INIS)

    Net current enhancement to levels in excess of the beam current has been observed in gases at pressures excess of 50 torr. We delineate the regimes where enhancement is observed. The experimental results fall into two very distinct classes; current enhancement at injection where the beam is only slightly displaced and current enhancement clearly associated with the high amplitude hose instability. A careful theoretical and experimental study of the diagnostics revealed no fundamental flaws although there are several complex and unlikely scenarios which could introduce fictitious current enhancement. Theoretical efforts indicate several mechanisms for generating enhancement but none of the theories can account for the detailed observations. 4 references, 4 figures

  9. Fast wave current drive

    Energy Technology Data Exchange (ETDEWEB)

    Goree, J.; Ono, M.; Colestock, P.; Horton, R.; McNeill, D.; Park, H.

    1985-07-01

    Fast wave current drive is demonstrated in the Princeton ACT-I toroidal device. The fast Alfven wave, in the range of high ion-cyclotron harmonics, produced 40 A of current from 1 kW of rf power coupled into the plasma by fast wave loop antenna. This wave excites a steady current by damping on the energetic tail of the electron distribution function in the same way as lower-hybrid current drive, except that fast wave current drive is appropriate for higher plasma densities.

  10. AIR LOAD BREAK SWITCH DESIGN PARAMETERS

    OpenAIRE

    Støa-Aanensen, Nina Sasaki

    2015-01-01

    Current interruption is vital in the power system, as this makes it possible to control the use of different loads, change the grid configuration, and minimize damage when faults occur. This thesis presents a study of the different switch design and test circuit parameters involved in medium voltage air load break switching and how they affect the thermal interrupting capability. Mediumvoltage load break switches are common in the distribution grid, and are a cheaper option ...

  11. Air reversing CO2 heat pumps

    OpenAIRE

    Andreassen, Hanne Elisabeth Bø

    2010-01-01

    CO2 is an environmentally friendly refrigerant that has a no global warming potential when used as refrigerant. The current refrigerants used for air conditioning in public transport are chemical components, and have a high global warming impact. The possibility of replacing the conventional refrigerants by CO2 is investigated for various parts of the transport sector. A possible CO2system for heating and cooling for public transport has been modeled and simulated. This system is a turntable ...

  12. Summary findings from the border air quality study

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-03-15

    The Border Air Quality Study (BAQS) is an ongoing study which supports the development of an international strategy for the Georgia Basin-Puget Sound airshed. The study investigates the association of health risks with the exposure to a range of air pollutants. It identified links between air pollutants and several health impacts ranging from asthma to birthweight. The tools developed for studying air quality provide greater spatial resolution, thus enabling the identification of pollution hot spots that require monitoring and intervention. The tools also provide spatially accurate exposure data for future research and enable land-use decisions that reduce risk to the most vulnerable populations, including children and the elderly. The study found that traffic-related air pollution is an additional risk factor for disease, such as bronchiolitis, asthma and middle ear infections in children. Although air pollution is a known risk factor for cardiovascular disease, relatively few studies have evaluated the effects of chronic exposures. Therefore, the BAQS is currently assessing the relationship between air quality and cardiovascular diseases in the Metro Vancouver area, with particular attention to the combined effects of traffic-related air pollution and noise pollution. Wood smoke was also found to be an important source of air pollution, even in urban centres. The study showed that building design and ventilation can help reduce infiltration of air pollutants into buildings. It was concluded that despite some concerns, the air quality in the Georgia-Basin-Puget Sound region is good compared to other major metropolitan areas. Air quality managers can use the study to evaluate different policy scenarios and the associated economic costs of air pollution. 5 figs.

  13. EN EL AIRE / In the air

    Directory of Open Access Journals (Sweden)

    Andrés López Fernández

    2011-11-01

    Full Text Available RESUMEN En el aire es un viaje a la primera mitad del siglo XX que nos tratará de acercar la frescura y oportunidad de las calles corredor y los jardines en la ciudad vertical. Se inicia en 1909 en Nueva York, con la publicación por la revista Life de La Torre del Globo, se acerca al Inmueble-Villas y al Plan Obus para Argel de Le Corbusier, y finaliza en 1952 con el proyecto para el conjunto residencial de Golden Lane en Londres de A. y P. Smithson. Fragmentos para la ciudad vertical que se construía sobre papel, tras el espejo, paralela en el tiempo, pero muy distinta a la ciudad real, con el objetivo entre otros de integrar arquitectura y naturaleza. Esas propuestas siguen teniendo hoy un gran valor, en un panorama en que el espacio público ligado a la vivienda colectiva, prácticamente ha desaparecido, y el esfuerzo que se demanda al arquitecto se centra, en tejer a modo de encaje de bolillos, una fachada que envuelva un programa de vivienda, funcional y espacialmente obsoleto.SUMMARY In the air, is a journey to the first half of the twentieth century that will try to bring us to the freshness and opportunity of the corridor streets and gardens in the vertical city. It begins in 1909 in New York, with the publication in Life magazine of the Globe Tower, it approaches the Immeubles-Villas and Plan Obus for Algiers by Le Corbusier, and ends in 1952 with the project for the Golden Lane Estate residential complex in London, by A. and P. Smithson. Fragments for the vertical city that was constructed on paper, behind the mirror, parallel in time, but was very different from the real city, with the aim, inter alia, of integrating architecture and nature. These proposals continue to have great value today, in a scenario where the public space linked to the collective home has virtually disappeared, and the effort that is demanded of the architect focuses on weaving a facade like bobbin lace around a functionally and spatially obsolete housing

  14. Impact of air quality guidelines on COPD sufferers

    Science.gov (United States)

    Liu, Youcheng; Yan, Shuang; Poh, Karen; Liu, Suyang; Iyioriobhe, Emanehi; Sterling, David A

    2016-01-01

    Background COPD is one of the leading causes of morbidity and mortality in both high- and low-income countries and a major public health burden worldwide. While cigarette smoking remains the main cause of COPD, outdoor and indoor air pollution are important risk factors to its etiology. Although studies over the last 30 years helped reduce the values, it is not very clear if the current air quality guidelines are adequately protective for COPD sufferers. Objective This systematic review was to summarize the up-to-date literature on the impact of air pollution on the COPD sufferers. Methods PubMed and Google Scholar were utilized to search for articles related to our study’s focus. Search terms included “COPD exacerbation”, “air pollution”, “air quality guidelines”, “air quality standards”, “COPD morbidity and mortality”, “chronic bronchitis”, and “air pollution control” separately and in combination. We focused on articles from 1990 to 2015. We also used articles prior to 1990 if they contained relevant information. We focused on articles written in English or with an English abstract. We also used the articles in the reference lists of the identified articles. Results Both short-term and long-term exposures to outdoor air pollution around the world are associated with the mortality and morbidity of COPD sufferers even at levels below the current air quality guidelines. Biomass cooking in low-income countries was clearly associated with COPD morbidity in adult nonsmoking females. Conclusion There is a need to continue to improve the air quality guidelines. A range of intervention measures could be selected at different levels based on countries’ socioeconomic conditions to reduce the air pollution exposure and COPD burden. PMID:27143874

  15. Molecular Air Data Clear Air Turbulence Sensor: MADCAT Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Clear air turbulence (CAT), often referred to as "air pockets," is attributed to Kelvin-Helmholtz instabilities at altitudes usually above 18,000ft, often without...

  16. Molecular Air Data Clear Air Turbulence Sensor: MADCAT Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Clear air turbulence (CAT), often referred to as "air pockets," is attributed to Kelvin-Helmholtz instabilities at altitudes generally above 18,000ft, often in the...

  17. Simulation of Gravity Currents Using VOF Model

    Institute of Scientific and Technical Information of China (English)

    邹建锋; 黄钰期; 应新亚; 任安禄

    2002-01-01

    By the Volume of Fluid (VOF) multiphase flow model two-dimensional gravity currents with three phases including air are numerically simulated in this article. The necessity of consideration of turbulence effect for high Reynolds numbers is demonstrated quantitatively by LES (the Large Eddy Simulation) turbulence model. The gravity currents are simulated for h ≠ H as well as h = H, where h is the depth of the gravity current before the release and H is the depth of the intruded fluid. Uprising of swell occurs when a current flows horizontally into another lighter one for h ≠ H. The problems under what condition the uprising of swell occurs and how long it takes are considered in this article. All the simulated results are in reasonable agreement with the experimental results available.

  18. Enhancing indoor air quality –The air filter advantage

    OpenAIRE

    Vannan Kandi Vijayan; Haralappa Paramesh; Sundeep Santosh Salvi; Alpa Anil Kumar Dalal

    2015-01-01

    Air pollution has become the world's single biggest environmental health risk, linked to around 7 million deaths in 2012 according to a recent World Health Organisation (WHO) report. The new data further reveals a stronger link between, indoor and outdoor air pollution exposure and cardiovascular diseases, such as strokes and ischemic heart disease, as well as between air pollution and cancer. The role of air pollution in the development of respiratory diseases, including acute respiratory in...

  19. BOOK REVIEW: The Current Comparator

    Science.gov (United States)

    Petersons, Oskars

    1989-01-01

    . One would hardly find a standards laboratory today without an instrument employing a current comparator. The NRC program, now nearing the end of its third decade, has resulted in a large number of papers in technical journals. The fact that the results of the current-comparator program are now documented in a well-written book is a most welcome development. The material in the book is well organized and divided into seven chapters. Chapter 1 deals very briefly with the historical aspects of the development, including related work in other organizations. Chapter 2 is the longest, occupying one third of the book. It presents the background theory; the definitions and origins of the errors; and the related concepts and devices including two-stage current transformers, electronic methods for improving the performance of current transformers, and null detectors. The idea of the current comparator is developed starting from Ampere's law; and then progressing to the practical realization of measuring the line integral of the magnetic field surrounding an electric current. Such an approach, as opposed to the more common methods of analyzing transformers, has a tutorial value in explaining how the current balance is achieved. Such analysis is intuitive for air-core sensing coils with infinitesimal cross-sections and uniform winding densities. The intuitive understanding, however, becomes less obvious when high-permeability magnetic cores are used. The subject of errors is discussed thoroughly. For errors of magnetic origin, ample experimental data are provided to support the hypothesis for the cause of such errors. The cause is discussed in a macroscopic sense (non-uniform effective permeability along the torus) without going into design and processing details which could be responsible for the non-uniformities. For capacitive errors, equations have been developed to compute them from geometrical considerations. Techniques are presented to reduce both types of errors shielding

  20. Air sampling in the workplace

    International Nuclear Information System (INIS)

    This report provides technical information on air sampling that will be useful for facilities following the recommendations in the NRC's Regulatory Guide 8.25, Revision 1, ''Air sampling in the Workplace.'' That guide addresses air sampling to meet the requirements in NRC's regulations on radiation protection, 10 CFR Part 20. This report describes how to determine the need for air sampling based on the amount of material in process modified by the type of material, release potential, and confinement of the material. The purposes of air sampling and how the purposes affect the types of air sampling provided are discussed. The report discusses how to locate air samplers to accurately determine the concentrations of airborne radioactive materials that workers will be exposed to. The need for and the methods of performing airflow pattern studies to improve the accuracy of air sampling results are included. The report presents and gives examples of several techniques that can be used to evaluate whether the airborne concentrations of material are representative of the air inhaled by workers. Methods to adjust derived air concentrations for particle size are described. Methods to calibrate for volume of air sampled and estimate the uncertainty in the volume of air sampled are described. Statistical tests for determining minimum detectable concentrations are presented. How to perform an annual evaluation of the adequacy of the air sampling is also discussed

  1. A Breath of Fresh Air: Addressing Indoor Air Quality

    Science.gov (United States)

    Palliser, Janna

    2011-01-01

    Indoor air pollution refers to "chemical, biological, and physical contamination of indoor air," which may result in adverse health effects (OECD 2003). The causes, sources, and types of indoor air pollutants will be addressed in this article, as well as health effects and how to reduce exposure. Learning more about potential pollutants in home…

  2. Indoor Air Quality in Schools: Clean Air Is Good Business.

    Science.gov (United States)

    Guarneiri, Michele A.

    2003-01-01

    Describes the effect of poor indoor air quality (IAQ) on student health, the cost of safeguarding good IAQ, the cause of poor IAQ in schools, how to tell whether a school has an IAQ problem, and how the U.S. Environmental Protection Agency can help schools improve indoor air quality though the use of their free "Indoor Air Quality Tools for…

  3. Properties of air and combustion products of fuel with air

    Science.gov (United States)

    Poferl, D. J.; Svehla, R. A.

    1975-01-01

    Thermodynamic and transport properties have been calculated for air, the combustion products of natural gas and air, and combustion products of ASTM-A-1 jet fuel and air. Properties calculated include: ratio of specific heats, molecular weight, viscosity, specific heat, thermal conductivity, Prandtl number, and enthalpy.

  4. Optimization of air ducts for nuclear reactor power generation station

    International Nuclear Information System (INIS)

    In the optimization study on the heating, ventilating and air conditions system in Nuclear Reactor Power Generation Station, proper arrangement of air ducts has been studied using the experimental and analytical investigation from a viewpoint of duct arrangement optimization. This study consists of two parts. Part I is optimization of air ducts in the corridors and Part II is optimization of air duct in each room. In part I, from viewpoints of confinement of radioactive materials in facilities having possible radioactive contamination and improvement of thermal environment for workers, the authors have studied air ducts system in which fresh air is supplied to corridors and heat removal and ventilation for each room are performed by transferring air from the corridors, instead of current ducts system with supply duct to each room. In part II, the condenser room with complex configuration and large space, and the electrical equipment room with simple space are selected for model areas. Based on these studies, experimental and analytical investigation (using a three-dimensional thermal hydraulic analysis) technique has been established, and the effective design method for duct arrangement of HVAC design has been verified for Boiling Water Reactor Power Station. The air-duct arrangements optimized in this study are applied to an Advanced Boiling Water Reactor Power Station in trial and reduction of the air-duct quantity is confirmed

  5. Shaft Current Protection

    OpenAIRE

    Rabuzin, Tin

    2015-01-01

    Shaft current protection in hydro and turbo generators is an important generatorprotection issue. Currents owing in the generator shaft might damagegenerator bearings which, in turn, could reduce operating time and cause largenancial losses. Therefore, it is important to prevent operation of the generatorunder conditions of high shaft currents.In this project, task was to develop measurement and protection system thatis able to operate under certain conditions. Measurement device has to be ab...

  6. Air travel, life-style, energy use and environmental impact

    Energy Technology Data Exchange (ETDEWEB)

    Krueger Nielsen, S.

    2001-09-01

    The overall aim of this project is to investigate the linkages between energy use, life style and environmental impact. As a case of study, this report investigates the future possibilities for reducing the growth in greenhouse gas emissions from commercial civil air transport, that is passenger air travel and airfreight. The season for this choice of focus is that we found that commercial civil air transport may become a relatively large energy consumer and greenhouse gas emitter in the future. For example, according to different scenarios presented by Intergovernmental Panel on Climate Change (IPCC), commercial civil air transport's fuel burn may grow by between 0,8 percent a factor of 1,6 and 16 between 1990 and 2050 and 2050. The actual growth in fuel consumption will depend on the future growth in airborne passenger travel and freight and the improvement rate for the specific fuel efficiency. As a central mid-term estimate the IPCC foresees that the fuel consumption may grow by around 3 percent per year until 2015. This report looks into the possibilities for reducing the growth in air traffic, as well as the possibilities for reducing the specific fuel consumption, to achieve an environmentally sustainable development. For commercial civil air transport the main challenge seems to lie in the strong growth rates currently envisioned by the aeronautical industry for the next decades. Like it is the case with most other types of (fossil) energy intensive activities the bulk of air traffic is currently performed in and between industrialised countries. In an environmentally sustainable World countries should aim at distributing resources evenly between the World's citizens. Therefore, on the longer term, there are tremendous challenges to be overcome. Achieving environmentally sustainable commercial civil air transport will first of all require that people living in currently industrialised countries stop travelling ever more by air each year. As it is

  7. Assessment of SRS ambient air monitoring network

    Energy Technology Data Exchange (ETDEWEB)

    Abbott, K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Jannik, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-08-03

    Three methodologies have been used to assess the effectiveness of the existing ambient air monitoring system in place at the Savannah River Site in Aiken, SC. Effectiveness was measured using two metrics that have been utilized in previous quantification of air-monitoring network performance; frequency of detection (a measurement of how frequently a minimum number of samplers within the network detect an event), and network intensity (a measurement of how consistent each sampler within the network is at detecting events). In addition to determining the effectiveness of the current system, the objective of performing this assessment was to determine what, if any, changes could make the system more effective. Methodologies included 1) the Waite method of determining sampler distribution, 2) the CAP88- PC annual dose model, and 3) a puff/plume transport model used to predict air concentrations at sampler locations. Data collected from air samplers at SRS in 2015 compared with predicted data resulting from the methodologies determined that the frequency of detection for the current system is 79.2% with sampler efficiencies ranging from 5% to 45%, and a mean network intensity of 21.5%. One of the airmonitoring stations had an efficiency of less than 10%, and detected releases during just one sampling period of the entire year, adding little to the overall network intensity. By moving or removing this sampler, the mean network intensity increased to about 23%. Further work in increasing the network intensity and simulating accident scenarios to further test the ambient air system at SRS is planned

  8. INVESTIGATION OF TIGHTLY COUPLED SINS/GPS INTEGRATION MIDCOURSE GUIDANCE FOR AIR-TO-AIR MISSILES

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    The applied problems of SINS/GPS integration navigation system existing in midcourse guidance of air-to-air missiles have been investigated recently. In comparison with those investigations existing in current publications, a new tightly coupled SINS/GPS integration navigation system for air-to-air missiles, based on the decorrelated pseudo-range approach, is presented in this paper. Because of high jamming and dynamic of air-to-air missiles, inertial velocity aiding GPS receiver is used to provide a more accurate, jam-resistant measurement for midcourse guidance systems. A tracking error estimator is designed to distinguish the correlation that existed between pseudo-range measurements and inertial information. It is found better to regard inertial velocity aiding errors as the noise of which statistical properties are unknown. So using mixed Kalman/minimax filtering theory, one can obtain the new tracking error estimator with simple and robust algorithm through constructing a composite filter consisting of two parts: Kalman filter for the noise of known statistics and minimax filter for the unknown. In order to ensure this simple estimator stability, a new method is proposed to choose its parameters, based on Khargonekars work. Moreover, it is demonstrated that the given method also ensures the proposed estimator optimality. All the work mentioned above is involved in the tightly coupled SINS/GPS integration midcourse system design in which a set of low-accuracy inertial components is shared by SINS and autopilot. Simulation results of a certain type of air-to-air missile are presented. Due to decorrelation by the tracking error estimator, only small white noise of pseudo-range measurements remains. So it is shown that application of the new midcourse guidance system results in better guidance accuracy, higher jam-resistance.

  9. Aeromicrobiology/air quality

    Science.gov (United States)

    Andersen, Gary L.; Frisch, A.S.; Kellogg, Christina A.; Levetin, E.; Lighthart, Bruce; Paterno, D.

    2009-01-01

    The most prevalent microorganisms, viruses, bacteria, and fungi, are introduced into the atmosphere from many anthropogenic sources such as agricultural, industrial and urban activities, termed microbial air pollution (MAP), and natural sources. These include soil, vegetation, and ocean surfaces that have been disturbed by atmospheric turbulence. The airborne concentrations range from nil to great numbers and change as functions of time of day, season, location, and upwind sources. While airborne, they may settle out immediately or be transported great distances. Further, most viable airborne cells can be rendered nonviable due to temperature effects, dehydration or rehydration, UV radiation, and/or air pollution effects. Mathematical microbial survival models that simulate these effects have been developed.

  10. Air Pollution in Europe

    International Nuclear Information System (INIS)

    In spite of improvements relative to air pollution, there is still much to do. more than thirty millions of European people are exposed to sulfur dioxide concentrations superior to guide values for health fixed by European Union, 20% of ecosystems in Europe are above the critical charges in the area of acidification and 33% concern eutrophication. Relative to the carbon dioxide, it is not sure that European Union realize the objective to stabilize the emissions for the year 2000 at the level of the year 1990, because of the increasing of automobile traffic and the energy consumption. Four subjects are presented: the climatic change, acidification and eutrophication, tropospheric ozone and air quality. (N.C.)

  11. Hot Air Engines

    Directory of Open Access Journals (Sweden)

    P. Stouffs

    2011-01-01

    Full Text Available Invented in 1816, the hot-air engines have known significant commercial success in the nineteenth century, before falling into disuse. Nowadays they enjoy a renewed interest for some specific applications. The "hot-air engines" family is made up of two groups: Stirling engines and Ericsson engines. The operating principle of Stirling and Ericsson engines, their troubled history, their advantages and their niche applications are briefly presented, especially in the field of micro-combined heat and power, solar energy conversion and biomass energy conversion. The design of an open cycle Ericsson engine for solar application is proposed. A first prototype of the hot part of the engine has been built and tested. Experimental results are presented.

  12. Air transport system

    CERN Document Server

    Schmitt, Dieter

    2016-01-01

    The book addresses all major aspects to be considered for the design and operation of aircrafts within the entire transportation chain. It provides the basic information about the legal environment, which defines the basic requirements for aircraft design and aircraft operation. The interactions between  airport, air traffic management and the airlines are described. The market forecast methods and the aircraft development process are explained to understand the very complex and risky business of an aircraft manufacturer. The principles of flight physics as basis for aircraft design are presented and linked to the operational and legal aspects of air transport including all environmental impacts. The book is written for graduate students as well as for engineers and experts, who are working in aerospace industry, at airports or in the domain of transport and logistics.

  13. The weak currents

    International Nuclear Information System (INIS)

    The main facts known on the structure of the weak hadronic current are given. An attempt is made to elucidate the physical meaning of different hypotheses such as C.V.C., PCAC, SU(3) and angle theta, chiral algebra, which have led to progress in the understanding of weak interactions. The central problem to overcome in order to specify the structure of the hadronic current is the fact that gaps remain in the knowledge of strong interactions. However a solution has been found by assuming that the weak current is a combination of the currents associated with exact or approximate symmetries of strong interactions

  14. Quantization of interface currents

    Energy Technology Data Exchange (ETDEWEB)

    Kotani, Motoko [AIMR, Tohoku University, Sendai (Japan); Schulz-Baldes, Hermann [Department Mathematik, Universität Erlangen-Nürnberg, Erlangen (Germany); Villegas-Blas, Carlos [Instituto de Matematicas, Cuernavaca, UNAM, Cuernavaca (Mexico)

    2014-12-15

    At the interface of two two-dimensional quantum systems, there may exist interface currents similar to edge currents in quantum Hall systems. It is proved that these interface currents are macroscopically quantized by an integer that is given by the difference of the Chern numbers of the two systems. It is also argued that at the interface between two time-reversal invariant systems with half-integer spin, one of which is trivial and the other non-trivial, there are dissipationless spin-polarized interface currents.

  15. Superconducting current generators

    International Nuclear Information System (INIS)

    After a brief summary of the principle of energy storage and liberation with superconducting coils,two current generators are described that create currents in the range 600 to 1400 A, used for two storage experiments of 25 kJ and 50 kJ respectively. The two current generators are: a) a flux pump and b) a superconducting transformer. Both could be developed into more powerful units. The study shows the advantage of the transformer over the flux pump in order to create large currents. The efficiencies of the two generators are 95 per cent and 40 to 60 per cent respectively. (author)

  16. Current and Current Fluctuations in Quantum Shuttles

    DEFF Research Database (Denmark)

    Jauho, Antti-Pekka; Flindt, Christian; Novotny, Tomas;

    2005-01-01

    We review the properties of electron shuttles, i.e., nanoelectromechanical devices that transport electrons one by one by utilizing a combination of electronic and mechanical degrees of freedom. We focus on the extreme quantum limit, where the mechanical motion is quantized. We introduce the main...... theoretical tools needed for the analysis, e.g., generalized master equations and Wigner functions, and we outline the methods how the resulting large numerical problems can be handled. Illustrative results are given for current, noise, and full counting statistics for a number of model systems. Throughout...

  17. Fast Air Temperature Sensors

    DEFF Research Database (Denmark)

    Hendricks, Elbert

    1998-01-01

    The note documents briefly work done on a newly developed sensor for making fast temperature measurements on the air flow in the intake ports of an SI engine and in the EGR input line. The work reviewed has been carried out in close cooperation with Civ. Ing. Michael Føns, the author (IAU......) and Spencer C. Sorenson (ET). The theory which decribes in detail the overall dynamic chracteristics of the sensor was developed at IAU, DTU....

  18. Urban air quality

    International Nuclear Information System (INIS)

    Since 1950 the world population has more than doubled, and the global number of cars has increased by a factor of 10. In the same period the fraction of people living in urban areas has increased by a factor of 4. In year 2000 this will amount to nearly half of the world population. About 20 urban regions will each have populations above 10 million people. Seen over longer periods, pollution in major cities tends to increase during the built up phase, they pass through a maximum and are then again reduced, as abatement strategies are developed. In the industrialised western world urban air pollution is in some respects in the last stage with effectively reduced levels of sulphur dioxide and soot. In recent decades however, the increasing traffic has switched the attention to nitrogen oxides, organic compounds and small particles. In some cities photochemical air pollution is an important urban problem, but in the northern part of Europe it is a large-scale phenomenon, with ozone levels in urban streets being normally lower than in rural areas. Cities in Eastern Europe have been (and in many cases still are) heavily polluted. After the recent political upheaval, followed by a temporary recession and a subsequent introduction of new technologies, the situation appears to improve. However, the rising number of private cars is an emerging problem. In most developing countries the rapid urbanisation has so far resulted in uncontrolled growth and deteriorating environment. Air pollution levels are here still rising on many fronts. Apart from being sources of local air pollution, urban activities are significant contributors to transboundary pollution and to the rising global concentrations of greenhouse gasses. Attempts to solve urban problems by introducing cleaner, more energy-efficient technologies will generally have a beneficial impact on these large-scale problems. Attempts based on city planning with a spreading of the activities, on the other hand, may generate

  19. Urban air quality

    Science.gov (United States)

    Fenger, Jes

    Since 1950 the world population has more than doubled, and the global number of cars has increased by a factor of 10. In the same period the fraction of people living in urban areas has increased by a factor of 4. In year 2000 this will amount to nearly half of the world population. About 20 urban regions will each have populations above 10 million people. Seen over longer periods, pollution in major cities tends to increase during the built up phase, they pass through a maximum and are then again reduced, as abatement strategies are developed. In the industrialised western world urban air pollution is in some respects in the last stage with effectively reduced levels of sulphur dioxide and soot. In recent decades however, the increasing traffic has switched the attention to nitrogen oxides, organic compounds and small particles. In some cities photochemical air pollution is an important urban problem, but in the northern part of Europe it is a large-scale phenomenon, with ozone levels in urban streets being normally lower than in rural areas. Cities in Eastern Europe have been (and in many cases still are) heavily polluted. After the recent political upheaval, followed by a temporary recession and a subsequent introduction of new technologies, the situation appears to improve. However, the rising number of private cars is an emerging problem. In most developing countries the rapid urbanisation has so far resulted in uncontrolled growth and deteriorating environment. Air pollution levels are here still rising on many fronts. Apart from being sources of local air pollution, urban activities are significant contributors to transboundary pollution and to the rising global concentrations of greenhouse gasses. Attempts to solve urban problems by introducing cleaner, more energy-efficient technologies will generally have a beneficial impact on these large-scale problems. Attempts based on city planning with a spreading of the activities, on the other hand, may generate

  20. Air Facility System (AFS) Widget

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Air Facility System (AFS) widget allows users to enter a specific location and retrieve facilities in the area of interest for stationary sources of air...

  1. State of the Air 2015

    Science.gov (United States)

    ... Banners Social Media What's the State of Your Air ? Home > 2015 > States States State List FAQ Understanding ... Environment: Act Locally What You Can Do Healthy Air News Facebook Twitter Google Plus Instagram © American Lung ...

  2. Air Compliance Complaint Database (ACCD)

    Data.gov (United States)

    U.S. Environmental Protection Agency — THIS DATA ASSET NO LONGER ACTIVE: This is metadata documentation for the Region 7 Air Compliance Complaint Database (ACCD) which logs all air pollution complaints...

  3. Air Markets Program Data (AMPD)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Air Markets Program Data tool allows users to search EPA data to answer scientific, general, policy, and regulatory questions about industry emissions. Air...

  4. Aviary heating: control of air temperature heated by a set biomass gasifier-combustor in a co-current flow, using a frequency inverter; Aquecimento de aviarios: controle da temperatura do ar aquecido por um conjunto gaseificador-combustor de biomassa de fluxo concorrente, utilizando um inversor de frequencia

    Energy Technology Data Exchange (ETDEWEB)

    Santos, William Rosario dos [Universidade Presidente Antonio Carlos (UNIPAC), Ponte Nova, MG (Brazil); Silva, Jadir Nogueira; Oliveira Filho, Delly; Martins, Marcio Aredes; Oliveira, Jofran Luiz de [Universidade Federal de Vicosa (UFV), MG (Brazil)], Emails: jadir@ufv.br, delly@ufv.br, aredes@ufv.br, jofran.oliveira@ufv.br

    2009-07-01

    One of the problems with using the gasifier for heating purposes in poultry facilities is the waste of energy during the day, once the equipment does not have control of the thermal and power generated. During this period, the difference in temperature between the air and the standard for the birds inside the building is lower than when compared with the nocturnal period. During the day, the temperature inside the poultry house is controlled by curtains, which occurs without diminishing the biomass burning. Another way to control the temperature is the shutdown of the system, which requires the constant attention of the operator. In this way, there is a potential for energy savings if the thermal power could be controlled according to the demand, which can be represented by the temperature gradient. The purpose of this study was to control the temperature of exhaustion air from a set combustor-gasifier (down draft), based on the model developed by Martin et al. (2006), through the control of speed of the fan engine and also controlling the flow contributions of primary and secondary air in the combustor. The experiment was carried out in the Energy and Pre-processing of Agricultural Products areas, at the Department of Agricultural Engineering - Federal University of Vicosa. (author)

  5. Air transparent soundproof window

    International Nuclear Information System (INIS)

    A soundproof window or wall which is transparent to airflow is presented. The design is based on two wave theories: the theory of diffraction and the theory of acoustic metamaterials. It consists of a three-dimensional array of strong diffraction-type resonators with many holes centered on each individual resonator. The negative effective bulk modulus of the resonators produces evanescent wave, and at the same time the air holes with subwavelength diameter existed on the surfaces of the window for macroscopic air ventilation. The acoustic performance levels of two soundproof windows with air holes of 20mm and 50mm diameters were measured. The sound level was reduced by about 30 - 35dB in the frequency range of 400 - 5,000Hz with the 20mm window, and by about 20 - 35dB in the frequency range of 700 - 2,200Hz with the 50mm window. Multi stop-band was created by the multi-layers of the window. The attenuation length or the thickness of the window was limited by background noise. The effectiveness of the soundproof window with airflow was demonstrated by a real installation

  6. Air transparent soundproof window

    Directory of Open Access Journals (Sweden)

    Sang-Hoon Kim

    2014-11-01

    Full Text Available A soundproof window or wall which is transparent to airflow is presented. The design is based on two wave theories: the theory of diffraction and the theory of acoustic metamaterials. It consists of a three-dimensional array of strong diffraction-type resonators with many holes centered on each individual resonator. The negative effective bulk modulus of the resonators produces evanescent wave, and at the same time the air holes with subwavelength diameter existed on the surfaces of the window for macroscopic air ventilation. The acoustic performance levels of two soundproof windows with air holes of 20mm and 50mm diameters were measured. The sound level was reduced by about 30 - 35dB in the frequency range of 400 - 5,000Hz with the 20mm window, and by about 20 - 35dB in the frequency range of 700 - 2,200Hz with the 50mm window. Multi stop-band was created by the multi-layers of the window. The attenuation length or the thickness of the window was limited by background noise. The effectiveness of the soundproof window with airflow was demonstrated by a real installation.

  7. Air transparent soundproof window

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang-Hoon, E-mail: shkim@mmu.ac.kr [Division of Marine Engineering, Mokpo National Maritime University, Mokpo 530-729, R. O. Korea (Korea, Republic of); Lee, Seong-Hyun [Korea Institute of Machinery and Materials, Yuseong-Gu, Daejeon 305-343, R. O. Korea (Korea, Republic of)

    2014-11-15

    A soundproof window or wall which is transparent to airflow is presented. The design is based on two wave theories: the theory of diffraction and the theory of acoustic metamaterials. It consists of a three-dimensional array of strong diffraction-type resonators with many holes centered on each individual resonator. The negative effective bulk modulus of the resonators produces evanescent wave, and at the same time the air holes with subwavelength diameter existed on the surfaces of the window for macroscopic air ventilation. The acoustic performance levels of two soundproof windows with air holes of 20mm and 50mm diameters were measured. The sound level was reduced by about 30 - 35dB in the frequency range of 400 - 5,000Hz with the 20mm window, and by about 20 - 35dB in the frequency range of 700 - 2,200Hz with the 50mm window. Multi stop-band was created by the multi-layers of the window. The attenuation length or the thickness of the window was limited by background noise. The effectiveness of the soundproof window with airflow was demonstrated by a real installation.

  8. CODEX and RUSET air oxidation experiments

    International Nuclear Information System (INIS)

    In the late phase of a severe accident after the failure of the lower head, or in shut-down state with open reactor vessel the interaction of air with high temperature core materials can be expected. The intense oxidation of zirconium components can strongly affect the evolution of the severe accident scenario and chemical interaction of air with fission products can influence the radiological source term due to the volatilization of ruthenium oxide. The KFKI Atomic Energy Institute initiated an experimental program in order to extend our knowledge in this field and to provide data for model development and better estimation of the consequences of air ingress type accidents. Two integral tests were performed in 1998-1999 with electrically heated nine-rod pressurized water reactor type bundles in the CODEX (Core Degradation Experiment) facility. The CODEX-AIT-1 (Air Ingress Test) and AIT-2 experiments indicated the acceleration of oxidation phenomena and core degradation process in air atmosphere under severe accident conditions. The degradation process was accompanied with zirconium-nitride formation and release of large number of aerosol particles, some of which contained uranium. The enhanced fission product release was not addressed in these tests. The oxidation behavior and release of fission products in high temperature air is investigated in the current RUSET program (Ruthenium Separate Effect Tests) 2002-2004. The first series of experiments was performed with fission product simulants mixed into ZrO2 or UC2 powder. Fast oxidation and release of Ru and other fission products was observed. The formed oxides deposited in the cold part of the facility and only few percent of the inventory reached the room temperature samplers. In 2003-2004 the RUSET experiments will be continued with short fuel rod segments, containing inactive fission product simulant materials. (author)

  9. Magnetodynamic waves in the air

    International Nuclear Information System (INIS)

    The paper describes experiments to search for a variable magnetic field close to a rechargeable conductive flat plate and a ball in the air, as well as an experiment looking for a variable electric field near a rotating permanent magnet. It has been found that variable electric and magnetic fields do not induce each other within the measurement error. It means that rotary Maxwell's equations are not applicable in the near-field zone and the classical concept of displacement current in vacuum (air) has no physical meaning. A conclusion is made on the existence of transverse magnetodynamic waves. Statics and dynamics of the magnetic field near the permanent magnet rod are investigated experimentally. The methods to compute magnetodynamic waves from any source are presented. Four types of polarization of these waves are identified: linear, circular, toroidal and mixed. Concentration and deflection of magnetodynamic waves are observed on introducing inhomogeneity in the form of a ferrite rod into their propagation way, which is similar to diffraction in optics. Secondary magnetodynamic waves from the induced magnetic moments in atoms of ferrite are registered near its surface, which is like reflection in optics. Some ideas for observation of effects similar to dispersion and interference are presented for magnetodynamic waves. The structure and properties of electrodynamic, magnetodynamic and electromagnetic waves are discussed. The ideas of experiments to search for their unknown properties are described. In conclusion, technical applications of magnetodynamic waves such as magnetography, magnetic tomography and other are considered. - Highlights: ► This paper is about new type of spatial-in-time disturbance (wave)- magnetodynamic waves. ► Theoretical and experimental evidences of existence the waves are done. ► The general properties of this waves are considered and suggestions regarding research new useful properties are done.

  10. Human preference for air movement

    DEFF Research Database (Denmark)

    Toftum, Jørn; Melikov, Arsen Krikor; Tynel, A.;

    2002-01-01

    Human preference for air movement was studied at slightly cool, neutral, and slightly warm overall thermal sensations and at temperatures ranging from 18 deg.C to 28 deg.C. Air movement preference depended on both thermal sensation and temperature, but large inter-individual differences existed...... between subjects. Preference for less air movement was linearly correlated with draught discomfort, but the percentage of subjects who felt draught was lower than the percentage who preferred less air movement....

  11. Air quality assessment for Portugal

    OpenAIRE

    Monteiro, A; Miranda, A. I.; C. Borrego; R. Vautard

    2007-01-01

    According to the Air Quality Framework Directive, air pollutant concentration levels have to be assessed and reported annually by each European Union member state, taking into consideration European air quality standards. Plans and programmes should be implemented in zones and agglomerations where pollutant concentrations exceed the limit and target values. The main objective of this study is to perform a long-term air quality simulation for Portugal, using the CHIMERE chemistry-transport mod...

  12. Iron-Air Rechargeable Battery

    Science.gov (United States)

    Narayan, Sri R. (Inventor); Prakash, G.K. Surya (Inventor); Kindler, Andrew (Inventor)

    2014-01-01

    Embodiments include an iron-air rechargeable battery having a composite electrode including an iron electrode and a hydrogen electrode integrated therewith. An air electrode is spaced from the iron electrode and an electrolyte is provided in contact with the air electrode and the iron electrodes. Various additives and catalysts are disclosed with respect to the iron electrode, air electrode, and electrolyte for increasing battery efficiency and cycle life.

  13. Air quality management in China: Issues, challenges, and options

    Institute of Scientific and Technical Information of China (English)

    Shuxiao Wang; Jiming Hao

    2012-01-01

    This article analyzed the control progress and current status of air quality,identified the major air pollution issues and challenges in future,proposed the long-term air pollution control targets,and suggested the options for better air quality in China.With the continuing growth of economy in the next 10-15 years,China will face a more severe situation of energy consumption,electricity generation and vehicle population leading to increase in multiple pollutant emissions.Controlling regional air pollution especially fine particles and ozone,as well as lowering carbon emissions from fossil fuel consumption will be a big challenge for the country.To protect public health and the eco-system,the ambient air quality in all Chinese cities shall attain the national ambient air quality standards (NAAQS)and ambient air quality guideline values set by the World Health Organization (WHO).To achieve the air quality targets,the emissions of SO2,NOx,PM10,and volatile organic compounds (VOC) should decrease by 60%,40%,50%,and 40%,respectively,on the basis of that in 2005.A comprehensive control policy focusing on multiple pollutants and emission sources at both the local and regional levels was proposed to mitigate the regional air pollution issue in China.The options include development of clean energy resources,promotion of clean and efficient coal use,enhancement of vehicle pollution control,implementation of synchronous control of multiple pollutants including SO2,NOx,VOC,and PM emissions,joint prevention and control of regional air pollution,and application of climate friendly air pollution control measures.

  14. Agriculture Communication in Malaysia: The Current Situation

    Directory of Open Access Journals (Sweden)

    Md. S. Hassan

    2010-01-01

    Full Text Available Problem statement: Without doubt, it is important to expose and educate farmers with the current and updated agriculture information. To implement this, the related agriculture agencies in Malaysia should consider the best channels for them in spreading the needed valuable agriculture information to the farmers. The question that can be raised now, can the mass media be the right channel for agriculture information dissemination and is the mass media has been utilized in disseminating the agriculture information to the farmers. Approach: This is a conceptual study discussing the usage of mass media in disseminating agriculture information. The data of this study are gained through literature analysis and document analysis. The data is presented descriptively. Results: Based on the analyses done, it was found that majority of Malaysian nowadays can afford to own their own mass media such as television, radio and internet. The number of available television channels, radio channels and newspapers either free or paid are encouraging. Currently, there are three television agriculture programs aired on RTM, while currently there are five agriculture radio programs aired on local radio stations, one program aired on Klasik National FM and the other four programs aired on four different states FM. For newspapers, there are two daily newspapers that provide agriculture information to their readers namely Utusan Malaysia and Berita Harian. Based on the data gained, usage of internet especially on website surfing must be encouraged among the farmers. Mobile web system initiated by five agriculture agencies in Malaysia is seen as a wise step for information dissemination and information sharing. Conclusion: Even though mass media in Malaysia has played its role in disseminating agriculture information, the number of programs and spaces produced and provided can be doubled, hence it is recommended that local giant agriculture based companies can play their

  15. A Wireless Sensor Network Air Pollution Monitoring System

    CERN Document Server

    Khedo, Kavi K; Mungur, Avinash; Mauritius, University of; Mauritius,; 10.5121/ijwmn.2010.2203

    2010-01-01

    Sensor networks are currently an active research area mainly due to the potential of their applications. In this paper we investigate the use of Wireless Sensor Networks (WSN) for air pollution monitoring in Mauritius. With the fast growing industrial activities on the island, the problem of air pollution is becoming a major concern for the health of the population. We proposed an innovative system named Wireless Sensor Network Air Pollution Monitoring System (WAPMS) to monitor air pollution in Mauritius through the use of wireless sensors deployed in huge numbers around the island. The proposed system makes use of an Air Quality Index (AQI) which is presently not available in Mauritius. In order to improve the efficiency of WAPMS, we have designed and implemented a new data aggregation algorithm named Recursive Converging Quartiles (RCQ). The algorithm is used to merge data to eliminate duplicates, filter out invalid readings and summarise them into a simpler form which significantly reduce the amount of dat...

  16. In-air and underwater hearing of the cormorant

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye; Wahlberg, Magnus; Christensen-Dalsgaard, Jakob

    Numerous studies have mapped the hearing abilities of birds in air but currently there is little or no data on how diving birds hear or react to sound under water. Therefore, it is unknown whether the ears and auditory system of diving birds are adapted to underwater hearing. In the present study......, we measured audiograms from wild-caught cormorant fledglings Phalacrocorax carbo sinensis) using auditory brainstem response (ABR). Each bird was anesthetized and the ABR was measured, first, in a sound attenuated and anechoic box in air and, secondly, with its head and neck submerged approximately....... The shape of the audiogram was similar to that reported for birds of the same size in air. The bandwidth and slopes of the audiogram were similar in air and water. In air the highest sensitivity was found at 1-2 kHz, while the most sensitive response was displaced towards lower frequencies (lower than...

  17. Shock-swallowing air sensor

    Science.gov (United States)

    Nugent, J.; Sakamoto, G. M.; Webb, L. D.; Couch, L. M.

    1979-01-01

    An air-data probe allows air to flow through it so that supersonic and hypersonic shock waves form behind pressure measuring orifices and tube instead of directly on them. Measured pressures are close to those in free-flowing air and are used to determine mach numbers of flying aircraft.

  18. Overview of Emerging Air Sensors

    Science.gov (United States)

    These slides will be presented at the 2014 National Ambient Air Monitoring Conference in Atlanta, GA during August 11-15, 2014. The goal is to provide an overview of air sensor technology and the audience will be primarily state air monitoring agencies and EPA Regions.

  19. Pupils' Understanding of Air Pollution

    Science.gov (United States)

    Dimitriou, Anastasia; Christidou, Vasilia

    2007-01-01

    This paper reports on a study of pupils' knowledge and understanding of atmospheric pollution. Specifically, the study is aimed at identifying: 1) the extent to which pupils conceptualise the term "air pollution" in a scientifically appropriate way; 2) pupils' knowledge of air pollution sources and air pollutants; and 3) pupils' knowledge of air…

  20. IMEF eddy current test

    International Nuclear Information System (INIS)

    The eddy current inspection technique which can detects in irradiated fuel rod cladding is described. Theoretical considerations for eddy current experiments devices, and experimental procedures are described. By doing the experiments on standard sample, conditions for defect test are established. (author). 1 tab., 9 figs., 5 refs

  1. Direct current transformer

    Science.gov (United States)

    Khanna, S. M.; Urban, E. W. (Inventor)

    1979-01-01

    A direct current transformer in which the primary consists of an elongated strip of superconductive material, across the ends of which is direct current potential is described. Parallel and closely spaced to the primary is positioned a transformer secondary consisting of a thin strip of magnetoresistive material.

  2. Charged weak currents

    International Nuclear Information System (INIS)

    In this review of charged weak currents we shall concentrate on inclusive high energy neutrino physics. The plan of this review is the following: general structure of charged current; new results on total cross-section; Callan-Gross relation; antiquark distribution; scaling violations and tests of QCD. At the end we will give a very short summary on multilepton physics

  3. Air Consumption Analysis of Air-Jet Weaving

    Directory of Open Access Journals (Sweden)

    RAJ KUMAR KHIANI

    2016-07-01

    Full Text Available In Textile industry, production is mostly key concern for Industry owner. This always has attracted researchers and machines manufacturers to make new developments in process and machines. Air-jet is one of the leading and successful highest productive weaving machines. However, it is now well established that due to add of charges of compressed air, manufacturing cost of air-jet weaving machine is higher as compared with rapier and projectile weaving machines. This is why countries having energy issues do not prefer air-jet weaving machines comparing projectile weaving machines. In this regard, several researchers and machine manufacturers have continuously been working to improve the efficiency of air-jet weft insertion. However, industry practice is as important as design made by researchers. The aim of this research is to investigate the air consumption of air-jet weaving on industrial scale practice. In this study, five weaving machine of same manufacturer and model were selected. It was observed that despite of manufacturing same quality of fabric, air consumption was varying almost in all weaving machines. Conventionally, mill workers adopt hit and trial practice in weaving industry including airpressure setting which leads to variation of nozzle pressure. Main reason of disparity of air consumption in air-jet weaving machines may be variation of distance from compressor to weaving machines, number of joints, un-necessary valve opening and pipes leakages cause an increase of compressed air consumption.

  4. Enhancing indoor air quality –The air filter advantage

    Directory of Open Access Journals (Sweden)

    Vannan Kandi Vijayan

    2015-01-01

    Full Text Available Air pollution has become the world's single biggest environmental health risk, linked to around 7 million deaths in 2012 according to a recent World Health Organisation (WHO report. The new data further reveals a stronger link between, indoor and outdoor air pollution exposure and cardiovascular diseases, such as strokes and ischemic heart disease, as well as between air pollution and cancer. The role of air pollution in the development of respiratory diseases, including acute respiratory infections and chronic obstructive pulmonary diseases, is well known. While both indoor and outdoor pollution affect health, recent statistics on the impact of household indoor pollutants (HAP is alarming. The WHO factsheet on HAP and health states that 3.8 million premature deaths annually - including stroke, ischemic heart disease, chronic obstructive pulmonary disease (COPD and lung cancer are attributed to exposure to household air pollution. Use of air cleaners and filters are one of the suggested strategies to improve indoor air quality. This review discusses the impact of air pollutants with special focus on indoor air pollutants and the benefits of air filters in improving indoor air quality.

  5. Enhancing indoor air quality -The air filter advantage.

    Science.gov (United States)

    Vijayan, Vannan Kandi; Paramesh, Haralappa; Salvi, Sundeep Santosh; Dalal, Alpa Anil Kumar

    2015-01-01

    Air pollution has become the world's single biggest environmental health risk, linked to around 7 million deaths in 2012 according to a recent World Health Organisation (WHO) report. The new data further reveals a stronger link between, indoor and outdoor air pollution exposure and cardiovascular diseases, such as strokes and ischemic heart disease, as well as between air pollution and cancer. The role of air pollution in the development of respiratory diseases, including acute respiratory infections and chronic obstructive pulmonary diseases, is well known. While both indoor and outdoor pollution affect health, recent statistics on the impact of household indoor pollutants (HAP) is alarming. The WHO factsheet on HAP and health states that 3.8 million premature deaths annually - including stroke, ischemic heart disease, chronic obstructive pulmonary disease (COPD) and lung cancer are attributed to exposure to household air pollution. Use of air cleaners and filters are one of the suggested strategies to improve indoor air quality. This review discusses the impact of air pollutants with special focus on indoor air pollutants and the benefits of air filters in improving indoor air quality. PMID:26628762

  6. Voltage controlled current source

    International Nuclear Information System (INIS)

    A seven decade, voltage controlled current source is described for use in testing intermediate range nuclear instruments that covers the entire test current range of from 10 picoamperes to 100 microamperes. High accuracy is obtained throughout the entire seven decades of output current with circuitry that includes a coordinated switching scheme responsive to the input signal from a hybrid computer to control the input voltage to an antilog amplifier, and to selectively connect a resistance to the antilog amplifier output to provide a continuous output current source as a function of a preset range of input voltage. An operator controlled switch provides current adjustment for operation in either a real-time simulation test mode or a time response test mode. 6 figs

  7. Laboratory study of air sparging: Air flow visualization

    International Nuclear Information System (INIS)

    Laboratory flow visualization experiments, using glass beads as the porous medium, were conducted to study air sparging, an innovative technology for subsurface contaminant remediation. The purpose of these experiments was to observe how air flows through saturated porous media and to obtain a basic understanding of air plume formation and medium heterogeneity effects. The experiments indicate that air flow occurring in discrete, stable channels is the most probable flow behavior in medium to fine grained water saturated porous media and that medium heterogeneity plays an important role in the development of air channels. Several simulated scales of heterogeneities, from pore to field, have been studied. The results suggest that air channel formation is sensitive to the various scales of heterogeneities. Site-specific hydrogeologic settings have to be carefully reviewed before air sparging is applied to remediate sites contaminated by volatile organic compounds

  8. Microwave detection of air showers with the MIDAS experiment

    Science.gov (United States)

    Privitera, Paolo; Alekotte, I.; Alvarez-Muñiz, J.; Berlin, A.; Bertou, X.; Bogdan, M.; Boháčová, M.; Bonifazi, C.; Carvalho, W. R.; de Mello Neto, J. R. T.; Facal San Luis, P.; Genat, J. F.; Hollon, N.; Mills, E.; Monasor, M.; Reyes, L. C.; Rouille d'Orfeuil, B.; Santos, E. M.; Wayne, S.; Williams, C.; Zas, E.

    2011-03-01

    Microwave emission from Extensive Air Showers could provide a novel technique for ultra-high energy cosmic rays detection over large area and with 100% duty cycle. We describe the design, performance and first results of the MIDAS (MIcrowave Detection of Air Showers) detector, a 4.5 m parabolic dish with 53 feeds in its focal plane, currently installed at the University of Chicago.

  9. Microwave detection of air showers with the MIDAS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Privitera, Paolo [University of Chicago, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Alekotte, I. [Centro Atomico Bariloche and Instituto Balseiro (CNEA-UNCuyo-CONICET), 8400 San Carlos de Bariloche, Rio Negro (Argentina); Alvarez-Muniz, J. [Universidad de Santiago de Compostela, Departamento de Fisica de Particulas, Campus Sur, E-15782 Santiago de Compostela (Spain); Berlin, A. [University of Chicago, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Bertou, X. [Centro Atomico Bariloche and Instituto Balseiro (CNEA-UNCuyo-CONICET), 8400 San Carlos de Bariloche, Rio Negro (Argentina); Bogdan, M.; Bohacova, M. [University of Chicago, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Bonifazi, C. [Univ. Federal do Rio de Janeiro (UFRJ), Instituto de Fisica, Cidade Universitaria, Caixa Postal 68528, 21945- 970 Rio de Janeiro, RJ (Brazil); Carvalho, W.R. [Universidad de Santiago de Compostela, Departamento de Fisica de Particulas, Campus Sur, E-15782 Santiago de Compostela (Spain); Mello Neto, J.R.T. de [Univ. Federal do Rio de Janeiro (UFRJ), Instituto de Fisica, Cidade Universitaria, Caixa Postal 68528, 21945- 970 Rio de Janeiro, RJ (Brazil); Facal San Luis, P.; Genat, J.F.; Hollon, N.; Mills, E.; Monasor, M.; Reyes, L.C.; Rouille d' Orfeuil, B. [University of Chicago, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Santos, E.M. [Univ. Federal do Rio de Janeiro (UFRJ), Instituto de Fisica, Cidade Universitaria, Caixa Postal 68528, 21945- 970 Rio de Janeiro, RJ (Brazil); Wayne, S.; Williams, C. [University of Chicago, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States)

    2011-03-15

    Microwave emission from Extensive Air Showers could provide a novel technique for ultra-high energy cosmic rays detection over large area and with 100% duty cycle. We describe the design, performance and first results of the MIDAS (MIcrowave Detection of Air Showers) detector, a 4.5 m parabolic dish with 53 feeds in its focal plane, currently installed at the University of Chicago.

  10. Indoor air quality control techniques. Radon, formaldehyde, combustion products

    International Nuclear Information System (INIS)

    This book reviews and evaluates existing indoor air quality control techniques. The indoor air pollutants of most concern are radon, formaldehyde, and certain combustion products-nitrogen dioxide, carbon monoxide, carbon dioxide, and various respirable particles. Many techniques exist to control the concentration of these pollutants and other indoor pollutants that are only now being recognized as significant. The purpose of the book is to provide a current review and evaluation of these control techniques

  11. The use of scientific information in setting ambient air standards.

    OpenAIRE

    Jordan, B C; Richmond, H M; McCurdy, T

    1983-01-01

    The Clean Air Act, as amended in 1977, requires periodic review and revision of all national ambient air quality standards (NAAQS) to insure that they are based on the latest scientific information. This article presents an overview of how EPA currently reviews and establishes NAAQS. The role of scientific information and expertise in the process is illustrated by a review of several key issues faced in the development of the proposed revisions to the carbon monoxide NAAQS. Finally, a risk an...

  12. Validation of a 3-D hemispheric nested air pollution model

    OpenAIRE

    Frohn, L. M.; Christensen, J.H.; Brandt, J; C. Geels; Hansen, K. M.

    2003-01-01

    Several air pollution transport models have been developed at the National Environmental Research Institute in Denmark over the last decade (DREAM, DEHM, ACDEP and DEOM). A new 3-D nested Eulerian transport-chemistry model: REGIonal high resolutioN Air pollution model (REGINA) is based on modules and parameterisations from these models as well as new methods. The model covers the majority of the Northern Hemisphere with currently one nest...

  13. Ionization current sensing; Jonstroem-maetning

    Energy Technology Data Exchange (ETDEWEB)

    Aengeby, Jakob; Goeras, Anders; Nytomt, Jan [Hoerbiger Control Systems AB, Aamaal, (Sweden)

    2012-05-15

    Ion current measurements give information on the combustion in the cylinders of an internal combustion engine in run time, cycle by cycle. Ion sense has been used in gasoline engines for many years for detection of knock and misfire, combustion stability and for air to fuel ratio estimation. However, the use of ion sense in industrial gas engines has been limited, despite the potential of ion sense. The objective with the project is to investigate which combustion process information that can be retrieved using ion sense applied to industrial lean burn engines using pre-chambers for the ignition in which case the spark plug is encapsulated in the pre-chamber. Experiments show that ion current measured in the pre-chamber can successfully be used to retrieve information from the in-cylinder combustion process. It is possible to detect misfire and to some extent knock. It is also possible to optimize the ignition and hence minimize emissions and optimize the performance by using the ion current measured in the pre- chamber. A statistical signal processing approach to use more than one ion current feature in the estimation of combustion parameters was evaluated on a heavy duty gas engine. By using more than one feature the performance of in cylinder air to fuel ratio estimation was improved.

  14. Control Technologies for Room Air-conditioner and Packaged Air-conditioner

    Science.gov (United States)

    Ito, Nobuhisa

    Trends of control technologies about air-conditioning machineries, especially room or packaged air conditioners, are presented in this paper. Multiple air conditioning systems for office buildings are mainly described as one application of the refrigeration cycle control technologies including sensors for thermal comfort and heating/ cooling loads are also described as one of the system control technologies. Inverter systems and related technologies for driving variable speed compressors are described in both case of including induction motors and brushless DC motors. Technologies for more accurate control to meet various kind of regulations such as ozone layer destruction, energy saving and global warming, and for eliminating harmonic distortion of power source current, as a typical EMC problem, will be urgently desired.

  15. Indoor air quality/air infiltration in selected low-energy houses

    International Nuclear Information System (INIS)

    Indoor air quality and air infiltration were measured in 16 low-energy California houses. Eleven has gas stoves; all had average infiltration rates of 0.5 h-1 of less, recent construction dates, low natural ventilation, and no mechanical ventilation. HCHO levels in 12 houses and radon-222 and NO2 levels in all houses were measured using passive monitors. Blower door measurements and local weather data were used to calculate average infiltration rates during the monitoring period. Correlation of pollutant concentrations with infiltration rates and building characteristics indicate that new houses with average heating season infiltration rates less than 0.5 h-1 do not necessarily experience poor indoor air quality, HCHO and radon-222 levels in new houses exceeded the lowest currently proposed standards or guidelines, and much higher levels probably exist elsewhere. Therefore, some strategy for identifying 'problem' houses is needed. We recommend an approach for future research in this area. (Author)

  16. Air-breathing Rocket Engine Test

    Science.gov (United States)

    1999-01-01

    This Quick Time movie depicts the Rocketdyne static test of an air-breathing rocket. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's advanced Transportation Program at the Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  17. The Air Toxics Health Effects Database (ATHED)

    International Nuclear Information System (INIS)

    The Air Toxics Health Effects Database (ATHED) is currently used by the EPA's Office of Air Quality Planning and Standards (OAQPS) to support risk assessments for the Residual Risk Program. An assessment of the residual risk is required to be performed at a specified time (typically 8years) following the promulgation of a technology-based Maximum Achievable Control Technologies (MACT) standard. The goal of the Residual Risk Program is to assure that the risk that remains after MACT standards are implemented (i.e., the 'residual risk') is acceptable, and if not, to propose additional regulations to mitigate those risks. ATHED maintains all available reference values for each chemical as separate data records, and includes values for all exposure durations (acute, short-term, subchronic and chronic). These values are used as benchmarks to determine acceptable exposure levels to the hazardous air pollutants (HAPs) listed in Section 112 of the Clean Air Act. ATHED also provides useful background information on the uncertainty and/or modifying factors that were applied in the derivation of each reference value, as well as the point of departure and the critical study/studies. To facilitate comparisons across durations for a specific chemical, ATHED data can be graphically presented

  18. Situational Leadership in Air Traffic Control

    Science.gov (United States)

    Arvidsson, Marcus; Johansson, Curt R.; Ek, Asa; Akselsson, Roland

    2007-01-01

    In high-risk environments such as air traffic control, leadership on different levels plays a certain role in establishing, promoting, and maintaining a good safety culture. The current study aimed to investigate how leadership styles, leadership style adaptability, and over and under task leadership behavior differed across situations, operative conditions, leadership structures, and working tasks in an air traffic control setting. Study locations were two air traffic control centers in Sweden with different operational conditions and leadership structures, and an administrative air traffic management unit. Leadership was measured with a questionnaire based on Leader Effectiveness and Adaptability Description (LEAD; Blanchard, Zigarmi & Zigarmi, 2003; Hersey & Blanchard, 1988). The results showed that the situation had strong impact on the leadership in which the leadership behavior was more relationship oriented in Success and Group situations than in Hardship and Individual situations. The leadership adaptability was further superior in Success and Individual situations compared with Hardship and Group situations. Operational conditions, leadership structures and working tasks were, on the other hand, not associated with leadership behavior.

  19. Air density correction in ionization dosimetry

    International Nuclear Information System (INIS)

    Air density must be taken into account when ionization dosimetry is performed with unsealed ionization chambers. The German dosimetry protocol DIN 6800-2 states an air density correction factor for which current barometric pressure and temperature and their reference values must be known. It also states that differences between air density and the attendant reference value, as well as changes in ionization chamber sensitivity, can be determined using a radioactive check source. Both methods have advantages and drawbacks which the paper discusses in detail. Barometric pressure at a given height above sea level can be determined by using a suitable barometer, or data downloaded from airport or weather service internet sites. The main focus of the paper is to show how barometric data from measurement or from the internet are correctly processed. Therefore the paper also provides all the requisite equations and terminological explanations. Computed and measured barometric pressure readings are compared, and long-term experience with air density correction factors obtained using both methods is described

  20. A reference current source for the calibration of current measuring systems in dosimetry using ionisation chambers

    International Nuclear Information System (INIS)

    This work describes a newly developed, easily handled current source containing one 90Sr + 90Y Y beta emitter. Four different currents from 7x10-11A to 4x10-14A are supplied. From 5 to 10 control measurements were performed for each of the four currents during a period of eight months. The standard deviation of the values of these control measurements, corrected to a reference air density and for radioactive decay, was between 0,07% and 0,4% with respect to the mean values obtained during the eight months. The relative standard deviation of the single values belonging to a control measurement carried out on one day under constant ambient conditions amounts to approximately one fourth of the values quoted above. The current source was utilized in a number of laboratories in the PTB and proved its reliability for checking current measuring systems in dosimetry with ionization chambers. (orig.)

  1. Current status of research and related activities in NAA application

    Energy Technology Data Exchange (ETDEWEB)

    Ab. Khalik bin Haji Wood [Malaysia Institute for Nuclear Technology Research, Bangi, Selangor (Malaysia)

    1999-10-01

    Current activities of Analytical Chemistry Group of MINT (Malaysia Institute for Nuclear Technology Research) laboratory for elemental analysis of trace amounts in environmental samples such as air particulate matter (on air filter), soils/sediments, water, flora/fauna, oil sludge/waste sludge, and tailing/blasting slag and others, utilizing particularly NAA (Neutron Activation Analysis) method are reviewed. The laboratory participates in the IAEA-organized Interlaboratory Comparison Studies to ensure the analytical system. Other activities include analytical chemistry services with ICP-mass spectrometry and GC/GCMS to compliment the NAA and, moreover, air and marine pollution studies with participation in the UNDP/RCA/IAEA project. (S. Ohno)

  2. Current status of research and related activities in NAA application

    International Nuclear Information System (INIS)

    Current activities of Analytical Chemistry Group of MINT (Malaysia Institute for Nuclear Technology Research) laboratory for elemental analysis of trace amounts in environmental samples such as air particulate matter (on air filter), soils/sediments, water, flora/fauna, oil sludge/waste sludge, and tailing/blasting slag and others, utilizing particularly NAA (Neutron Activation Analysis) method are reviewed. The laboratory participates in the IAEA-organized Interlaboratory Comparison Studies to ensure the analytical system. Other activities include analytical chemistry services with ICP-mass spectrometry and GC/GCMS to compliment the NAA and, moreover, air and marine pollution studies with participation in the UNDP/RCA/IAEA project. (S. Ohno)

  3. Workplace air monitoring and sampling practices at DOE facilities

    International Nuclear Information System (INIS)

    The Pacific Northwest Laboratory (PNL) surveyed the current air monitoring and sampling practices at U.S. Department of Energy (DOE) facilities as a part of an air monitoring upgrade task. A comprehensive questionnaire was developed and distributed to DOE contractors through the DOE field offices. Twenty-six facilities returned a completed questionnaire. Questionnaire replies indicate a large diversity in air sampling and monitoring practices among DOE facilities. The differences among the facilities exist in monitoring and sampling instrumentation, procedures, calibration, analytical methods, detection levels, and action levels. Many of these differences could be attributed to different operational needs. 5 references, 2 figures, 2 tables

  4. Polymer electrolyte fuel cells: flow field for efficient air operation

    Energy Technology Data Exchange (ETDEWEB)

    Buechi, F.N.; Tsukada, A.; Haas, O.; Scherer, G.G. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    A new flow field was designed for a polymer electrolyte fuel cell stack with an active area of 200 cm{sup 2} for operation at low air stoichiometry and low air over pressure. Optimum of gas flow and channel dimensions were calculated based on the required pressure drop in the fluid. Single cells and a bi-cell stack with the new flow field show an improved current/voltage characteristic when operated at low air stoichiometries as compared to that of the previous non optimized design. (author) 4 figs., 3 refs.

  5. CFD simulation of an offshore air intake and exhaust system

    OpenAIRE

    Sirevaag, Ola

    2015-01-01

    The main purpose is to investigate whether the exhaust gases from an offshore turbine can be rerouted to heat the air entering the turbine system, thus keeping air humidity concentration above acceptable levels. To ensure this, temperature of the incoming airflow must be above 4,5 degrees Celsius. Currently the exhaust is vented out to the atmosphere and an electrical anti-icing system is used to heat the air intake. The objective of this thesis is therefore to make a CFD model in OpenFOAM to...

  6. Demonstrations of magnetic phenomena: Measuring the air permeablity using tablets

    CERN Document Server

    Lara, Vitor O M; Faria, Daiara; Vieira, Leonardo P

    2015-01-01

    We use a tablet to determine experimentally the dependencies of the magnetic field (B) on the electrical current and on the axial distance from a coil (z). Our data shows a good precision on the inverse cubic dependence of the magnetic field on the axial distance, $B \\propto z^{-3}$. We obtain with good accuracy the value of air permeability $\\mu_{air}$. We also observe the same dependence of $B$ on $z$ when considering a magnet instead of a coil. Although our estimates are obtained through simple data fits, we also perform a more sophisticated error analysis, confirming the result for $\\mu_{air}$.

  7. Indoor air. Seminar of Zentrale Informationsstelle, Umweltberatung Bayern. Vol. 2

    International Nuclear Information System (INIS)

    This seminar dealt with the subject of indoor air pollution and welcomed participants from environmental consultancy agencies and authorities and institutions related with environmental protection. Leading scientists from research and authorities presented the current state of knowledge abut the risks of indoorair pollution. The papers contained in these proceedings addressed: room climate and sick-building syndrome; allergens in indoor spaces; pollutants emitted by exemplary building materials; pollutant levels of organic compounds in indoor spaces; air quality in motor vehicle interiors; indoor air pollution - risk assessment and need for actions. (Uhe)

  8. Adobe AIR for Android -sovelluskehitys

    OpenAIRE

    Palovuori, Jani

    2011-01-01

    Tässä opinnäytetyössä käsitellään sovelluskehitystä Android-laitteille Adoben AIR for Android -tekniikkaa hyväksi käyttäen. Tavoitteena on esitellä sovelluskehityksen periaatteita Adoben Flash-tekniikkaan pohjautuvan AIR for Android -teknologian kannalta. Työ on tehty Yleisradio Oy:n toimeksiantona ja toimii johdatuksena AIR-sovelluksen kehittämiseen AIR for Android -teknologialla. Työssä esitellään yleisesti rikkaat internet-sovellukset ja käydään tarkemmin läpi Adoben AIR-teknologia sek...

  9. Air Risk Information Support Center

    Energy Technology Data Exchange (ETDEWEB)

    Shoaf, C.R.; Guth, D.J. [Environmental Protection Agency, Washington, DC (United States)

    1990-12-31

    The Air Risk Information Support Center (Air RISC) was initiated in early 1988 by the US Environmental Protection Agency`s (EPA) Office of Health and Environmental Assessment (OHEA) and the Office of Air Quality Planning and Standards (OAQPS) as a technology transfer effort that would focus on providing information to state and local environmental agencies and to EPA Regional Offices in the areas of health, risk, and exposure assessment for toxic air pollutants. Technical information is fostered and disseminated by Air RISCs three primary activities: (1) a {open_quotes}hotline{close_quotes}, (2) quick turn-around technical assistance projects, and (3) general technical guidance projects. 1 ref., 2 figs.

  10. Effect of Pulse Current on the Tensile Deformation of SUS304 Stainless Steel

    Science.gov (United States)

    Li, Xifeng; Wang, Shen; Zhao, Shuangjun; Ding, Wei; Chen, Jun; Wu, Guohong

    2015-12-01

    The effect of pulse current on the mechanical properties of SUS304 metastable austenitic stainless steel was studied by tension test with and without air-cooling under different current densities. The microstructural variations at different conditions were also studied by SEM, TEM, and Feritscope. A negative effect on the plasticity was observed when current pulse was applied without air-cooling. But when Joule heating resulting from current pulse was excluded by air-cooling, the elongation of SUS304 stainless steel was increased to 72.4% at a current density of 2.95 A/mm2, which is 23.3% higher than that tested without pulse current at room temperature. Pulse current can decrease the dislocation density and dislocation pile-ups. Furthermore, EP effect from pulse current can accelerate martensitic transformation and enhance TRIP effect. The mechanism of current-induced martensitic transformation was discussed from Gibbs free energy change.

  11. A smart indoor air quality sensor network

    Science.gov (United States)

    Wen, Jin

    2006-03-01

    The indoor air quality (IAQ) has an important impact on public health. Currently, the indoor air pollution, caused by gas, particle, and bio-aerosol pollutants, is considered as the top five environmental risks to public health and has an estimated cost of $2 billion/year due to medical cost and lost productivity. Furthermore, current buildings are especially vulnerable for chemical and biological warfare (CBW) agent contamination because the central air conditioning and ventilation system serve as a nature carrier to spread the released agent from one location to the whole indoor environment within a short time period. To assure the IAQ and safety for either new or existing buildings, real time comprehensive IAQ and CBW measurements are needed. With the development of new sensing technologies, economic and reliable comprehensive IAQ and CBW sensors become promising. However, few studies exist that examine the design and evaluation issues related to IAQ and CBW sensor network. In this paper, relevant research areas including IAQ and CBW sensor development, demand control ventilation, indoor CBW sensor system design, and sensor system design for other areas such as water system protection, fault detection and diagnosis, are reviewed and summarized. Potential research opportunities for IAQ and CBW sensor system design and evaluation are discussed.

  12. In the air

    OpenAIRE

    Andrés López Fernández

    2011-01-01

    RESUMEN En el aire es un viaje a la primera mitad del siglo XX que nos tratará de acercar la frescura y oportunidad de las calles corredor y los jardines en la ciudad vertical. Se inicia en 1909 en Nueva York, con la publicación por la revista Life de La Torre del Globo, se acerca al Inmueble-Villas y al Plan Obus para Argel de Le Corbusier, y finaliza en 1952 con el proyecto para el conjunto residencial de Golden Lane en Londres de A. y P. Smithson. Fragmentos para la ciudad vertical que se ...

  13. Method and device for measuring the smoke concentration in air

    International Nuclear Information System (INIS)

    The patent deals with a method and a device for measuring the smoke concentration in air. In a smoke chamber are located two electrodes, connected to a voltage source for forming a circuit in which a DC current flows. A radioactive radiation source to ionize the air molecules is located in the vicinity of the smoke chamber, so that the number of ionized air molecules which are formed is dependent upon the radiation intensity of the ion source and the concentration of smoke particles in the smoke chamber. The charging voltage will further imply that a cloud of high ion concentration is built up close to the surface of the electrodes. The ion cloud will be discharged capacitively upon a plurality of short voltages pulses applied to the electrodes to thereby result in current pulses substantially greater than the DC current flowing through the chamber. 8 figs

  14. Laboratory demonstration of runaway electron breakdown of air

    Energy Technology Data Exchange (ETDEWEB)

    Gurevich, A.V., E-mail: alex@lpi.ru [P.N. Lebedev Physical Institute, RAS, 53 Lenin Avenue, 119991 Moscow (Russian Federation); Mesyats, G.A.; Zybin, K.P. [P.N. Lebedev Physical Institute, RAS, 53 Lenin Avenue, 119991 Moscow (Russian Federation); Reutova, A.G.; Shpak, V.G.; Shunailov, S.A.; Yalandin, M.I. [Institute of Electrophysics, UB RAS, 106 Amundsen Str., 620016 Ekaterinburg (Russian Federation)

    2011-07-18

    Results of experiments demonstrating the phenomenon of runaway electron breakdown of atmospheric air under laboratory conditions are presented. As the discharge-initiating electron beam of duration ∼50 ps had passed through the electrode gap, a runaway electron avalanche current was detected in the electrode gap downstream of the anode grid and then breakdown occurred with picosecond stability. The maximum electron energy and the duration of the avalanche current corresponded to theoretical notions about the runaway electron breakdown of atmospheric air in a strong electric field. Breakdown did not occur at all or was considerably delayed when no initiating beam was used. -- Highlights: → Runaway electron air breakdown in laboratory experiments is demonstrated. → The discharge is initiated by electron beam of 50 ps duration. → The maximum electron energy and avalanche current duration correspond to the theory.

  15. Prediction of Indoor Air Exposure from Outdoor Air Quality Using an Artificial Neural Network Model for Inner City Commercial Buildings

    OpenAIRE

    Avril Challoner; Francesco Pilla; Laurence Gill

    2015-01-01

    NO2 and particulate matter are the air pollutants of most concern in Ireland, with possible links to the higher respiratory and cardiovascular mortality and morbidity rates found in the country compared to the rest of Europe. Currently, air quality limits in Europe only cover outdoor environments yet the quality of indoor air is an essential determinant of a person’s well-being, especially since the average person spends more than 90% of their time indoors. The modelling conducted in this res...

  16. Medicare Current Beneficiary Survey

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Characteristics and Perceptions of the Medicare Population Data from the 2010 Medicare Current Beneficiary Survey is a series of source books based on the...

  17. NOAA NDBC SOS - currents

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA NDBC SOS server is part of the IOOS DIF SOS Project. The stations in this dataset have currents data. Because of the nature of SOS requests, requests for...

  18. Current Resource Imagery Projects

    Data.gov (United States)

    Farm Service Agency, Department of Agriculture — Map showing coverage of current Resource imagery projects. High resolution/large scale Resource imagery is typically acquired for the U.S. Forest Service and other...

  19. Geothermal Energy: Current abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Ringe, A.C. (ed.)

    1988-02-01

    This bulletin announces the current worldwide information available on the technologies required for economic recovery of geothermal energy and its use as direct heat or for electric power production. (ACR)

  20. Rigid current Lie algebras

    OpenAIRE

    Goze, Michel; Remm, Elisabeth

    2006-01-01

    A current Lie algebra is contructed from a tensor product of a Lie algebra and a commutative associative algebra of dimension greater than 2. In this work we are interested in deformations of such algebras and in the problem of rigidity. In particular we prove that a current Lie algebra is rigid if it is isomorphic to a direct product gxg...xg where g is a rigid Lie algebra.

  1. Eddy current testing

    Energy Technology Data Exchange (ETDEWEB)

    Song, Sung Jin; Lee, Hyang Beom; Kim, Young Hwan [Soongsil Univ., Seoul (Korea, Republic of); Shin, Young Kil [Kunsan Univ., Gunsan (Korea, Republic of)

    2004-02-15

    Eddy current testing has been widely used for non destructive testing of steam generator tubes. In order to retain reliability in ECT, the following subjects were carried out in this study: numerical modeling and analysis of defects by using BC and RPC probes in SG tube, preparation of absolute coil impedance plane diagram by FEM. Signal interpretation of the eddy current signals obtained from nuclear power plants.

  2. Quadrant I description of current conditions

    International Nuclear Information System (INIS)

    In accordance with the requirements of the Consent Decree issued by the Ohio Attorney General's office on August 29, 1989 and with the RCRA Section 3008(h) Consent Order issued by the US Environmental Protection Agency, Region V (USEPA) on September 29, 1989, this report, which provides a Description of Current Conditions within Quadrant I of the Portsmouth Gaseous Diffusion Plant (PORTS) located in Piketon, Ohio, has been developed and submitted for approval. The objectives of this report are to provide data concerning: (1) the current state of knowledge of the environmental setting of Quadrant I of PORTS including ground water, surface water, soil and air; and (2) the extent of known, potential and suspected contamination of these segments of the environment in Quadrant I of the facility. This report is the initial step in the comprehensive RCRA Facility Investigation (RFI) currently underway at PORTS, and will provide a foundation for all subsequent activities related to the RFI in Quadrant I

  3. Progress Towards AIRS Science Team Version-7 at SRT

    Science.gov (United States)

    Susskind, Joel; Blaisdell, John; Iredell, Lena; Kouvaris, Louis

    2016-01-01

    The AIRS Science Team Version-6 retrieval algorithm is currently producing level-3 Climate Data Records (CDRs) from AIRS that have been proven useful to scientists in understanding climate processes. CDRs are gridded level-3 products which include all cases passing AIRS Climate QC. SRT has made significant further improvements to AIRS Version-6. At the last Science Team Meeting, we described results using SRT AIRS Version-6.22. SRT Version-6.22 is now an official build at JPL called 6.2.4. Version-6.22 results are significantly improved compared to Version-6, especially with regard to water vapor and ozone profiles. We have adapted AIRS Version-6.22 to run with CrIS/ATMS, at the Sounder SIPS which processed CrIS/ATMS data for August 2014. JPL AIRS Version-6.22 uses the Version-6 AIRS tuning coefficients. AIRS Version-6.22 has at least two limitations which must be improved before finalization of Version-7: Version-6.22 total O3 has spurious high values in the presence of Saharan dust over the ocean; and Version-6.22 retrieved upper stratospheric temperatures are very poor in polar winter. SRT Version-6.28 addresses the first concern. John Blaisdell ran the analog of AIRS Version-6.28 in his own sandbox at JPL for the 14th and 15th of every month in 2014 and all of July and October for 2014. AIRS Version-6.28a is hot off the presses and addresses the second concern.

  4. Updated ozone absorption cross section will reduce air quality compliance

    Science.gov (United States)

    Sofen, E. D.; Evans, M. J.; Lewis, A. C.

    2015-12-01

    Photometric ozone measurements rely upon an accurate value of the ozone absorption cross section at 253.65 nm. This has recently been re-evaluated by Viallon et al. (2015) as 1.8 % smaller than the accepted value (Hearn, 1961) used for the preceding 50 years. Thus, ozone measurements that applied the older cross section systematically underestimate the amount of ozone in air. We correct the reported historical surface data from North America and Europe and find that this modest change in cross section has a significant impact on the number of locations that are out of compliance with air quality regulations if the air quality standards remain the same. We find 18, 23, and 20 % increases in the number of sites that are out of compliance with current US, Canadian, and European ozone air quality health standards for the year 2012. Should the new cross-section value be applied, it would impact attainment of air quality standards and compliance with relevant clean air acts, unless the air quality target values themselves were also changed proportionately. We draw attention to how a small change in gas metrology has a global impact on attainment and compliance with legal air quality standards. We suggest that further laboratory work to evaluate the new cross section is needed and suggest three possible technical and policy responses should the new cross section be adopted.

  5. Air Pollution Studies in Metromanila and Catalysis Technology Towards Clean Air Philippines

    Science.gov (United States)

    Gallardo, S. M.

    - Considerable air quality and emission data gathered in Metropolitan Manila (MM) led to the development of automobile exhaust treatment catalysts as well as their continued improvement. Findings of a 5-year (1993-1998) collaborative work on the development of base metal oxide catalysts for automobile exhaust are summarized here. One study in 1991 reveals an average 16% increase in the number of motor vehicles in MM where 16% are new and the rest are old ones. Another study in 1992 shows the CO and hydrocarbon emission levels from different types of motor vehicles in MM as a function of the age of the vehicle, type of fuel, and the operating condition. Reports of the Department of Environment and Natural Resources (DENR) and other related studies also provided data showing the quality of air in MM. Currently, there are several requirements to further improve the catalyst performance towards the reduction of NOX and to develop catalyst-sorbent for simultaneous NOX-SOX removal. This is so because of the present condition of rain acidification that is found in certain places in MM. These air quality and emission data are needed not only to establish practical emission standards for motor vehicles and the stationary industries and power plants but also in the development of technologies for air pollution control and other clean technologies for cleaner air in the country.

  6. Building air exhaustion device

    International Nuclear Information System (INIS)

    An opening is formed on the side wall of a building such as of a nuclear power plant, and a blow out panel is held (supported) by a clip for closing the opening. A large-diameter pipeline is connected at one end to the opening so as to cover the blow out panel, and immersed at the other end in a pool water. When a pipeline such as of main steam pipelines is ruptured in the building, high temperature and high pressure coolants are flown out from the ruptured port, and the pressure in the building is elevated. The blow out panel falls off from the side of the building by the elevation of the pressure in the building. Steams or compressed air discharged from the opening is introduced to the pool through the large diameter pipeline, then the steams are condensed by the pool water and radioactive materials contained in the condensed steams are kept in the pool water. Radioactive materials contained in the released compression air are also removed into the pool water. (I.N.)

  7. EPA issues offshore air pollution regulations

    International Nuclear Information System (INIS)

    This paper reports that the Environmental Protection Agency has issued regulations equalizing offshore air pollution rules with onshore standards except in the Gulf of Mexico. The rules hold platforms and drilling rigs within 25 miles of states' seaward boundaries to the same state, local, and federal requirements as if they were located in the corresponding onshore areas. If EPA finds state regulations are adequate, it will delegate to the coastal state the implementation and enforcement authority for the OCS rules. Air emissions sources more than 25 miles offshore will be subject only to federal requirements. EPA said within 2 years the rules will result in significant benefits to certain onshore areas currently violating smog standards

  8. Air quality criteria for carbon monoxide

    International Nuclear Information System (INIS)

    The revised air quality criteria document for CO reviews and evaluates available scientific information on the health effects associated with exposure to the concentrations of CO found in ambient air. Although the document is not intended to be an exhaustive literature review, it is intended to cover all the pertinent literature through early 1991. The references cited in the document are, therefore, reflective of the present state of knowledge on those issues relevant to the subsequent review of the NAAQS for CO, currently set at 9 ppm (10 mg/cu m) for 8 h and 35 ppm (40 mg/cu m) for 1 h. Major gaps in knowledge also are identified. Although emphasis is placed on the presentation of health effects data, other scientific data are presented and evaluated in order to provide a better understanding of the nature, sources, distribution, measurement, and concentration of CO in the environment, as well as the measurement of population exposure to CO

  9. Air Turbines for Wave Energy Conversion

    Directory of Open Access Journals (Sweden)

    Manabu Takao

    2012-01-01

    Full Text Available This paper describes the present status of the art on air turbines, which could be used for wave energy conversion. The air turbines included in the paper are as follows: Wells type turbines, impulse turbines, radial turbines, cross-flow turbine, and Savonius turbine. The overall performances of the turbines under irregular wave conditions, which typically occur in the sea, have been compared by numerical simulation and sea trial. As a result, under irregular wave conditions it is found that the running and starting characteristics of the impulse type turbines could be superior to those of the Wells turbine. Moreover, as the current challenge on turbine technology, the authors explain a twin-impulse turbine topology for wave energy conversion.

  10. Microwave Regenerable Air Purification Device

    Science.gov (United States)

    Atwater, James E.; Holtsnider, John T.; Wheeler, Richard R., Jr.

    1996-01-01

    The feasibility of using microwave power to thermally regenerate sorbents loaded with water vapor, CO2, and organic contaminants has been rigorously demonstrated. Sorbents challenged with air containing 0.5% CO2, 300 ppm acetone, 50 ppm trichloroethylene, and saturated with water vapor have been regenerated, singly and in combination. Microwave transmission, reflection, and phase shift has also been determined for a variety of sorbents over the frequency range between 1.3-2.7 GHz. This innovative technology offers the potential for significant energy savings in comparison to current resistive heating methods because energy is absorbed directly by the material to be heated. Conductive, convective and radiative losses are minimized. Extremely rapid heating is also possible, i.e., 1400 C in less than 60 seconds. Microwave powered thermal desorption is directly applicable to the needs of Advance Life Support in general, and of EVA in particular. Additionally, the applicability of two specific commercial applications arising from this technology have been demonstrated: the recovery for re-use of acetone (and similar solvents) from industrial waste streams using a carbon based molecular sieve; and the separation and destruction of trichloroethylene using ZSM-5 synthetic zeolite catalyst, a predominant halocarbon environmental contaminant. Based upon these results, Phase II development is strongly recommended.

  11. Baltimore Air Toxics Study (BATS)

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, D.A. [Sullivan Environmental Consulting, Inc., Alexandria, VA (United States)

    1996-12-31

    The Baltimore Air Toxics Study is one of the three urban air toxics initiatives funded by EPA to support the development of the national air toxics strategy. As part of this project, the Air Quality Integrated Management System (AIMS) is under development. AIMS is designed to bring together the key components of urban air quality management into an integrated system, including emissions assessment, air quality modeling, and air quality monitoring. Urban area source emissions are computed for a wide range of pollutants and source categories, and are joined with existing point source emissions data. Measured air quality data are used to evaluate the adequacy of the emissions data and model treatments as a function of season, meteorological parameters, and daytime/nighttime conditions. Based on tested model performance, AIMS provides the potential to improve the ability to predict air quality benefits of alternative control options for criteria and toxic air pollutants. This paper describes the methods used to develop AIMS, and provides examples from its application in the Baltimore metropolitan area. The use of AIMS in the future to enhance environmental management of major industrial facilities also will be addressed in the paper.

  12. Comparison of indoor air and outdoor air contaminant concentrations

    OpenAIRE

    Pykhova, Ekaterina

    2014-01-01

    Since most people spend their time indoors, there has been increased interest in air pollution concen-trations. Number of very small liquid and solid particles suspended in the air is depending on different factors. But how should be decreased particle number? The field of this work is particulate matter concentration in the indoor and outdoor air. Measurements were carried out in number concentration. The Indoor-Outdoor correlation was de-termined in order to investigate normative parti...

  13. Cubesat Constellation Design for Air Traffic Monitoring

    Science.gov (United States)

    Nag, Sreeja; Rios, Joseph Lucio; Gerhardt, David; Pham, Camvu

    2015-01-01

    Suitably equipped global and local air traffic can be tracked. The tracking information may then be used for control from ground-based stations by receiving the Automatic Dependent Surveillance-Broadcast (ADS-B) signal. The ADS-B signal, emitted from the aircraft's Mode-S transponder, is currently tracked by terrestrial based receivers but not over remote oceans or sparsely populated regions such as Alaska or the Pacific Ocean. Lack of real-time aircraft time/location information in remote areas significantly hinders optimal planning and control because bigger "safety bubbles" (lateral and vertical separation) are required around the aircraft until they reach radar-controlled airspace. Moreover, it presents a search-and-rescue bottleneck. Aircraft in distress, e.g. Air France AF449 that crashed in 2009, take days to be located or cannot be located at all, e.g. Malaysia Airlines MH370 in 2014. In this paper, we describe a tool for designing a constellation of small satellites which demonstrates, through high-fidelity modeling based on simulated air traffic data, the value of space-based ADS-B monitoring and provides recommendations for cost-efficient deployment of a constellation of small satellites to increase safety and situational awareness in the currently poorly-served surveillance area of Alaska. Air traffic data has been obtained from the Future ATM Concepts Evaluation Tool (FACET), developed at NASA Ames Research Center, simulated over the Alaskan airspace over a period of one day. The simulation is driven by MATLAB with satellites propagated and coverage calculated using AGI's Satellite ToolKit(STK10).

  14. Jambu drying with cold air circulation

    Directory of Open Access Journals (Sweden)

    Alan Franco Barbosa

    2015-06-01

    Full Text Available The purpose of this study was to evaluate the drying process of jambu using cold air which is a technology that can add value to the horticultural food, improve the production rates and help in waste reduction. Initially, the vegetable is washed in water in order to remove residual impurities. Then, the roots are removed. The raw material is sanitized with 200 ppm (mg.L-1 of sodium hypochlorite (10 minutes. Therefore, the final rinse is carried out with a 5 ppm sodium hypochlorite bath for 10 minutes with the subsequent drainage of this water. The cold air-drying of jambu is performed under temperatures around 25 °C using an air conditioning system. A dehumidifier is used in order to reduce the product's relative humidity (54.6 ± 2.87. The process takes place in a room with an area of 4 square meters that remains shut during the process, which lasts a total time of 44 hours. Later, the product is stored in a high protective package to avoid moisture. Jambu centrifugation is not performed because its leaves are fragile. The cold air-dried jambu is in accordance with the current legislation regarding microbiological aspects. Also, it is well accepted by consumers and its centesimal composition is similar to fresh jambu. Other drying techniques can also be applied, such as hot air and ultrasound. Thus, considering sanitary and sensory aspects and chemical composition, the commercialization of dried jambu is feasible in terms of transport and handling.

  15. Surface Flux Modeling for Air Quality Applications

    Directory of Open Access Journals (Sweden)

    Limei Ran

    2011-08-01

    Full Text Available For many gasses and aerosols, dry deposition is an important sink of atmospheric mass. Dry deposition fluxes are also important sources of pollutants to terrestrial and aquatic ecosystems. The surface fluxes of some gases, such as ammonia, mercury, and certain volatile organic compounds, can be upward into the air as well as downward to the surface and therefore should be modeled as bi-directional fluxes. Model parameterizations of dry deposition in air quality models have been represented by simple electrical resistance analogs for almost 30 years. Uncertainties in surface flux modeling in global to mesoscale models are being slowly reduced as more field measurements provide constraints on parameterizations. However, at the same time, more chemical species are being added to surface flux models as air quality models are expanded to include more complex chemistry and are being applied to a wider array of environmental issues. Since surface flux measurements of many of these chemicals are still lacking, resistances are usually parameterized using simple scaling by water or lipid solubility and reactivity. Advances in recent years have included bi-directional flux algorithms that require a shift from pre-computation of deposition velocities to fully integrated surface flux calculations within air quality models. Improved modeling of the stomatal component of chemical surface fluxes has resulted from improved evapotranspiration modeling in land surface models and closer integration between meteorology and air quality models. Satellite-derived land use characterization and vegetation products and indices are improving model representation of spatial and temporal variations in surface flux processes. This review describes the current state of chemical dry deposition modeling, recent progress in bi-directional flux modeling, synergistic model development research with field measurements, and coupling with meteorological land surface models.

  16. Assessment of Environmentally Friendly Refrigerants for Window Air Conditioners

    OpenAIRE

    Shen, Bo; Bansal, Pradeep

    2014-01-01

    Window air conditioners (WAC) are cheap and sold in large numbers internationally as alternatives to central air-conditioning systems. There are nearly 57 million WACs currently operating within United States alone which account for approximately 1.5% of the total US residential energy use or about 0.21 quads per year. Due to global warming and other environmental concerns, there is a need to find an alternative to the currently used refrigerant R410a in WACs. There are several alternative re...

  17. Nitrogen fluorescence in air for observing extensive air showers

    Directory of Open Access Journals (Sweden)

    Tsunesada Y.

    2013-06-01

    Full Text Available Extensive air showers initiate the fluorescence emissions from nitrogen molecules in air. The UV-light is emitted isotropically and can be used for observing the longitudinal development of extensive air showers in the atmosphere over tenth of kilometers. This measurement technique is well-established since it is exploited for many decades by several cosmic ray experiments. However, a fundamental aspect of the air shower analyses is the description of the fluorescence emission in dependence on varying atmospheric conditions. Different fluorescence yields affect directly the energy scaling of air shower reconstruction. In order to explore the various details of the nitrogen fluorescence emission in air, a few experimental groups have been performing dedicated measurements over the last decade. Most of the measurements are now finished. These experimental groups have been discussing their techniques and results in a series of Air Fluorescence Workshops commenced in 2002. At the 8th Air Fluorescence Workshop 2011, it was suggested to develop a common way of describing the nitrogen fluorescence for application to air shower observations. Here, first analyses for a common treatment of the major dependences of the emission procedure are presented. Aspects like the contributions at different wavelengths, the dependence on pressure as it is decreasing with increasing altitude in the atmosphere, the temperature dependence, in particular that of the collisional cross sections between molecules involved, and the collisional de-excitation by water vapor are discussed.

  18. Tests on the stability of the displacement current in a cubic space; Untersuchungen zur Stabilitaet der Verdraengungsstroemung in einem Kubusraum

    Energy Technology Data Exchange (ETDEWEB)

    Gores, I.; Fitzner, K. [Technische Univ. Berlin (Germany). Hermann-Rietschel-Institut fuer Heizungs- und Klimatechnik

    2000-07-01

    Air current flow rates inside rooms have considerable effect on thermal comfort. Apart from the forced air currents of air conditioning systems, there are upward and downward currents near heat sources and heat sinks. If both types of air currents are superposed, the maximum air flow rate may increase, resulting in reduced thermal comfort. Greater internal loads in modern office buildings (e.g. call centres) lead one to expect increasing problems as air current flow rates get faster with increasing loads. [German] Die Luftgeschwindigkeiten in Innenraeumen haben einen wichtigen Einfluss auf die thermische Behaglichkeit. Neben den erzwungenen Luftstroemungen durch RLT-Anlagen beeinflussen insbesondere auch Auf- und Abtriebsstroemungen an Waermequellen bzw. -senken die Aufenthaltszone. Bei der Ueberlagerung der beiden Stroemungen kann es zu einer Verstaerkung der maximalen Luftgeschwindigkeit kommen, die zu Unbehaglichkeit fuehrt. Die Zunahme der inneren Lasten in heutigen Buerogebaeuden (z.B. Callcenter) laesst eine Verschaerfung des Problems erwarten, da die Luftgeschwindigkeiten mit steigender Last zunehmen. (orig.)

  19. Sights from the air

    Science.gov (United States)

    Tartara, P.

    2009-04-01

    The first aerial shots were taken by aerostat balloon during the second half of the nineteen century for military purpose and subsequently utilized for civilian, archaeological and town planning uses (Roman Forum 1900, Pompei 1910, Venezia 1913, etc.). Sights from the air have given the most objective representation of the landscape and traces progressively left by human activities. After the First World War the use of airplanes for photogrammetric shots suitable to create cartography (territorial map making) has permitted to realize a good basic documentation; successively it has been increased by aerial reconnaissance during the Second World War. Aerial shots by RAF, USAF and Luftwaffe brought to the establishment of rich aerial photograph Archives, particularly in Europe, which have had a very low utilization for the historical restoration of landscape. From the fifties, aerial documentation becomes systematic for different scale analysis and territorial planning. The use of satellite imagery and multispectral bands integrates the historical and recent aerial photographs; the former is particularly helpful for cartography updating, for large scale environmental analysis, for study and research of territories with not available air photographs or lacking in aerial shots. The amount and density of archaeological buried evidences, unknown at the most, is very substantial in Italy and in the whole Mediterranean area; here air-photo interpretation is being applied at advanced levels, but not systematically, since several decades. Some archaeological research teams, working for the knowledge of territorial cultural heritage, utilize historical and recent aerial photographs intensively (aerial photographs previous the II WW, just before the intensive and extensive use of mechanical means to till the land, preserve a large amount of traces or cropmarks of buried evidences; recent shots taken on different conditions of climate and crops, allow to see and read important

  20. Steadiness in Dilute Pyroclastic Density Currents

    Science.gov (United States)

    Andrews, B. J.

    2015-12-01

    Pyroclastic density currents (PDCs) are often unsteady, as evidenced by direct observations of dilute lobes or jets emerging from the fronts of larger currents and by deposits that indicate transient transport and depositional regimes. We used scaled experiments to investigate unsteadiness in dilute PDCs. The experimental currents were run in an 8.5x6.1x2.6 m tank and comprised heated or ambient temperature 20-μm talc powder turbulently suspended in air. Experiments were scaled such that densimetric and thermal Richardson numbers, Froude number, and particle Stokes and settling numbers were dynamically similar to natural dilute PDCs. Although the experiment Reynolds numbers are substantially lower than those of natural PDCs, the experiments are fully turbulent. Experiments were observed with video and high-speed cameras and high-frequency thermocouples. Currents were generated with total eruption durations of 100 s. Unsteadiness in source conditions was produced by interrupting supply for intervals, t, with durations of 1, 2.5, 5, and 10 s in the experimental runs at 35 and 70 s. When t3t>τ, unsteadiness decays such that at a distance of ~4Ut, the currents are again steady. Applied to natural dilute PDCs, our results suggest that currents and their resulting deposits, will only show evidence of unsteadiness if they are disrupted for many seconds and those breaks may "heal" over distances of 100s of meters.

  1. Air Quality and Climate Change

    International Nuclear Information System (INIS)

    Climate change and air quality are closely related: through the policy measures implemented to mitigate these major environmental threats but also through the geophysical processes that drive them. We designed, developed and implemented a comprehensive regional air quality and climate modeling System to investigate future air quality in Europe taking into account the combined pressure of future climate change and long range transport. Using the prospective scenarios of the last generation of pathways for both climate change (emissions of well mixed greenhouse gases) and air pollutants, we can provide a quantitative view into the possible future air quality in Europe. We find that ozone pollution will decrease substantially under the most stringent scenario but the efforts of the air quality legislation will be adversely compensated by the penalty of global warming and long range transport for the business as usual scenario. For particulate matter, the projected reduction of emissions efficiently reduces exposure levels. (authors)

  2. Clean air policy under the UNECE Convention on long-range transboundary air pollution: how are monitoring results "translated" to policy action

    Directory of Open Access Journals (Sweden)

    Johannessen T

    2009-01-01

    Full Text Available Concerning clean air policy, under the convention on long-range transboundary air pollution, the following themes are discussed: the history of observed effects; the public awareness and concern for the ecosystem health; the current scientific evidence; the development of the critical load concept, and its application for an effects-based abatement policy.

  3. Eddy current damper

    Science.gov (United States)

    Ellis, R. C.; Fink, R. A.; Rich, R. W.

    1989-01-01

    A high torque capacity eddy current damper used as a rate limiting device for a large solar array deployment mechanism is discussed. The eddy current damper eliminates the problems associated with the outgassing or leaking of damping fluids. It also provides performance advantages such as damping torque rates, which are truly linear with respect to input speed, continuous 360 degree operation in both directions of rotation, wide operating temperature range, and the capability of convenient adjustment of damping rates by the user without disassembly or special tools.

  4. Regularization of current algebra

    CERN Document Server

    Mickelsson, J

    1993-01-01

    In this talk I want to explain the operator substractions needed to regularize gauge currents in a second quantized theory. The case of space-time dimension $3+1$ is considered in detail. In presence of chiral fermions the regularization effects a modification of the local commutation relations of the currents by local Schwinger terms. In $1+1$ dimensions one gets the usual central extension (Schwinger term does not depend on background gauge field) whereas in $3+1$ dimensions one gets an anomaly linear in the background potential.

  5. Feedback cooling of currents

    Science.gov (United States)

    Washburn, Sean

    1989-02-01

    Just as feedback can be used to correct errors in the output voltages of amplifiers, it can also be used to remove noise from the current through a resistor. Such a feedback amplifier behaves as a refrigerator cooling the electrons in a resistor connnected to it. This principle has been recognized since the 1940s but has been largely ignored because the cooling power available from such refrigerators is miniscule. It is pointed out here that the method might be practical for cooling the currents in the microscopic circuits that are typical of modern electrical engineering and recent studies in transport physics.

  6. The Anderson Current Loop

    Science.gov (United States)

    Anderson, Karl F.

    1994-01-01

    Four-wire-probe concept applied to electrical-resistance transducers. Anderson current loop is excitation-and-signal-conditioning circuit suitable for use with strain gauges, resistance thermometers, and other electrical-resistance transducers mounted in harsh environments. Used as alternative to Wheatstone bridge. Simplifies signal-conditioning problem, enabling precise measurement of small changes in resistance of transducer. Eliminates some uncertainties in Wheatstone-bridge resistance-change measurements in flight research. Current loop configuration makes effects of lead-wire and contact resistances insignificantly small. Also provides output voltage that varies linearly with change in gauge resistance, and does so at double sensitivity of Wheatstone bridge.

  7. Photochemical air pollution syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Hamming, W.J.; MacBeth, W.C.; Chass, R.L.

    1967-01-01

    There are two distinct pollution problems in the Los Angeles Basin - one in winter, the other most frequently in summer and fall. In winter the concentrations of carbon monoxide, nitrogen oxides, sulfur dioxide and black filterable aerosols are higher than in summer, but the secondary pollutants such as ozone and photochemical oxidants are not as high. The photochemical air pollution syndrome is due to a pattern set by previous smog attacks. This pattern is due to low wind speeds, low inversion heights, a trajectory to carry the pollution and sufficient sunlight to photodissociate the nitrogen dioxide formed and to form nitric oxide and atomic oxygen. The results are high levels of oxidant or ozone and large quantities of particles. 5 references, 9 figures, 7 tables.

  8. Change in the air

    International Nuclear Information System (INIS)

    Aviation has a key part to play in the future protection of the environment. Such issues as climate change raise serious questions for all of us, but particularly for energy-intensive industries such as aviation, which makes a small but identifiable contribution to man's impact on the global climate. Airlines, such as British Airways, must strive to meet ever-higher standards of environmental performance. Environmental challenges facing the aviation industry are categorized as: noise, emissions and fuel efficiency, waste of energy, water and material, congestion in the air and on the ground, tourism and conservation. These headings have proved to be robust and our environmental programmes have, accordingly, been deployed under them

  9. metropolitana en Buenos Aires

    Directory of Open Access Journals (Sweden)

    Pedro Pírez

    2006-01-01

    Full Text Available In this paper, we present a description of some concrete processes that made up the transformations in the metropolitan configuration and functioning in Buenos Aires in the 1990s during the 20th Century. We are referring to components related to the impact of processes at the macro level (national and international pertaining to restructuring and globalisation. We aim to understand the “forces” that mediate between the global and the local arenas, identifying the actors and the relationships behind metropolitan changes as well as searching for the meaning that the city acquires and which is understood as “privatisation”. In the first section of the paper, this concept is made explicit.

  10. de Buenos Aires

    Directory of Open Access Journals (Sweden)

    Joaquín Linne

    2014-01-01

    Full Text Available Esta investigación explora la situación de los cibercafés en la Ciudad de Buenos Aires y de su principalpoblación, los adolescentes de sectores populares. Aunque en los últimos años millones de adolescentes abandonaronestos espacios como consecuencia de la ampliación de la Internet hogareña, en sectores popularesmuchos adolescentes aún continúan asistiendo en busca de recreación lúdico-comunicativa, información eintegración social. La metodología utilizada consiste en 40 entrevistas en profundidad, observaciones participantesy análisis de contenido de perfiles de Facebook (n: 200. Entre los resultados, se destaca que lasprincipales prácticas de estos adolescentes son comunicativas y que estos espacios funcionan para ellos comoherramientas de alfabetización digital, sociabilidad entre pares e inclusión ciudadana.

  11. Metal hydride air conditioner

    Institute of Scientific and Technical Information of China (English)

    YANG; Ke; DU; Ping; LU; Man-qi

    2005-01-01

    The relationship among the hydrogen storage properties, cycling characteristics and thermal parameters of the metal hydride air conditioning systems was investigated. Based on a new alloy selection model, three pairs of hydrogen storage alloys, LaNi4.4 Mn0.26 Al0.34 / La0.6 Nd0.4 Ni4.8 Mn0.2 Cu0. 1, LaNi4.61Mn0. 26 Al0.13/La0.6 Nd0.4 Ni4.8 Mn0.2 Cu0. 1 and LaNi4.61 Mn0.26 Al0.13/La0.6 Y0.4 Ni4.8 Mn0. 2, were selected as the working materials for the metal hydride air conditioning system. Studies on the factors affecting the COP of the system showed that higher COP and available hydrogen content need the proper operating temperature and cycling time,large hydrogen storage capacity, flat plateau and small hysterisis of hydrogen alloys, proper original input hydrogen content and mass ratio of the pair of alloys. It also needs small conditioning system was established by using LaNi4.61 Mn0.26 Al0. 13/La0.6 Y0.4 Ni4.8 Mn0.2 alloys as the working materials, which showed that under the operating temperature of 180℃/40℃, a low temperature of 13℃ was reached, with COP =0.38 and Wnet =0.09 kW/kg.

  12. Atmospheric Chemistry and Air Pollution

    OpenAIRE

    Gaffney, Jeffrey S.; Marley, Nancy A.

    2003-01-01

    Atmospheric chemistry is an important discipline for understanding air pollution and its impacts. This mini-review gives a brief history of air pollution and presents an overview of some of the basic photochemistry involved in the production of ozone and other oxidants in the atmosphere. Urban air quality issues are reviewed with a specific focus on ozone and other oxidants, primary and secondary aerosols, alternative fuels, and the potential for chlorine releases to amplify oxidant chemistry...

  13. Air and metal hydride battery

    Energy Technology Data Exchange (ETDEWEB)

    Lampinen, M.; Noponen, T. [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Applied Thermodynamics

    1998-12-31

    The main goal of the air and metal hydride battery project was to enhance the performance and manufacturing technology of both electrodes to such a degree that an air-metal hydride battery could become a commercially and technically competitive power source for electric vehicles. By the end of the project it was possible to demonstrate the very first prototype of the air-metal hydride battery at EV scale, achieving all the required design parameters. (orig.)

  14. Air pollution control in practice

    International Nuclear Information System (INIS)

    The book offers a comprehensive treatment of the subject, from air pollution monitoring and effects on human and animal health, on plants and materials, to pollution reduction measures, practical applications, and legal regulations. It intends to give the air pollution expert a basis for developing practicable solutions. Apart from the 'classic' pollutants, also radioactive air pollution is gone into. (DG) With 366 figs., 190 tabs

  15. Air pollution: Impact and prevention

    OpenAIRE

    SIERRA-VARGAS, MARTHA PATRICIA; Teran, Luis M.

    2012-01-01

    ABSTRACT Air pollution is becoming a major health problem that affects millions of people worldwide. In support of this observation, the World Health Organization estimates that every year, 2.4 million people die because of the effects of air pollution on health. Mitigation strategies such as changes in diesel engine technology could result in fewer premature mortalities, as suggested by the US Environmental Protection Agency. This review: (i) discusses the impact of air pollution on respirat...

  16. CATS-based Air Traffic Controller Agents

    Science.gov (United States)

    Callantine, Todd J.

    2002-01-01

    This report describes intelligent agents that function as air traffic controllers. Each agent controls traffic in a single sector in real time; agents controlling traffic in adjoining sectors can coordinate to manage an arrival flow across a given meter fix. The purpose of this research is threefold. First, it seeks to study the design of agents for controlling complex systems. In particular, it investigates agent planning and reactive control functionality in a dynamic environment in which a variety perceptual and decision making skills play a central role. It examines how heuristic rules can be applied to model planning and decision making skills, rather than attempting to apply optimization methods. Thus, the research attempts to develop intelligent agents that provide an approximation of human air traffic controller behavior that, while not based on an explicit cognitive model, does produce task performance consistent with the way human air traffic controllers operate. Second, this research sought to extend previous research on using the Crew Activity Tracking System (CATS) as the basis for intelligent agents. The agents use a high-level model of air traffic controller activities to structure the control task. To execute an activity in the CATS model, according to the current task context, the agents reference a 'skill library' and 'control rules' that in turn execute the pattern recognition, planning, and decision-making required to perform the activity. Applying the skills enables the agents to modify their representation of the current control situation (i.e., the 'flick' or 'picture'). The updated representation supports the next activity in a cycle of action that, taken as a whole, simulates air traffic controller behavior. A third, practical motivation for this research is to use intelligent agents to support evaluation of new air traffic control (ATC) methods to support new Air Traffic Management (ATM) concepts. Current approaches that use large, human

  17. "Air embolism during fontan operation"

    Directory of Open Access Journals (Sweden)

    Madan Mohan Maddali

    2014-01-01

    Full Text Available In patients with a right to left intracardiac shunt, air embolism results in an obligatory systemic embolization. Nonembolization of entrained air is described in a child with a single ventricle physiology who had earlier undergone bidirectional Glenn shunt construction and Damus-Kaye-Stansel anastomosis. The air entrainment was detected by intra-operative transesophageal echocardiography. The combined effect of a "diving bell" phenomenon and mild aortic valve regurgitation are suggested as the reasons for the confinement of air into the ventricle preventing catastrophic systemic embolization.

  18. Managing Air in Olympic Cities

    OpenAIRE

    Qing W. Tian; Peter Brimblecombe

    2008-01-01

    The 21st century Olympic Agenda aims to align itself with the concept of sustainable development and has driven improved environmental quality in host cities, such as the Green Games in Sydney 2000 and the planned Beijing 2008 Games and in London 2012 as the Low Carbon Games. Air quality has long been a concern of Olympic mega-cities, although the air quality plans and strategies have often seemed short-lived and unsustainable in the long term. We have explored air quality data and air pollut...

  19. Current topics in photovoltaics

    International Nuclear Information System (INIS)

    This book contains papers on current research in photovoltaics. Areas include: outdoor spectral odor radiation variations and their relationship to photovoltaic device performance, numerical modeling for analysis and design of solar cells, radiation damage mechanisms in GaAs and Si solar cells, and health and safety issues in the manufacturing of photovoltaic cells

  20. Second class weak currents

    International Nuclear Information System (INIS)

    The definition and general properties of weak second class currents are recalled and various detection possibilities briefly reviewed. It is shown that the existing data on nuclear beta decay can be consistently analysed in terms of a phenomenological model. Their implication on the fundamental structure of weak interactions is discussed

  1. Issues in neutral currents

    International Nuclear Information System (INIS)

    The experimental results on low energy confirming the structure of the effective Lagrangian of the weak neutral current processes as predicted by the Salam-Weinberg model are reviewed. Some possible modifications of the effective Lagrangian and the feasibility of their experimental verification are also considered. (P.L.)

  2. Effect of Air Outlet Angle on Air Distribution Performance Index

    Directory of Open Access Journals (Sweden)

    Isbeyeh W. Maid

    2013-05-01

    Full Text Available       In this paper a numerical study of velocity and temperature distribution in air conditioned space have been made. The computational model consists of the non-isothermal 3-D turbulent with (k-ε model. The numerical study is made to conduct air distribution in a room air-conditioned space with real interior dimensions (6×4×3m and to analyze the effect of changing angle of grille vanes on the flow pattern, velocity, and temperature distribution in the room under a set of different condition, and under a supply air temperature of 16˚C to examine the final result on air distribution performance index (ADPI.The results show a significant effect within the change of supply air angle, the maximum air distribution performance index (ADPI is 52% when air change per hour (ACH is equal to 10 at 16˚C inlet temperature with angle ( 15˚ down, and the minimum value of (ADPI is 20% when ACH is equal to 15 at 16˚C inlet temperature and angle ( degree. 

  3. AIR QUALITY IMPACTS OF LIQUEFIED NATURAL GAS IN THE SOUTH COAST AIR BASIN OF CALIFORNIA

    Energy Technology Data Exchange (ETDEWEB)

    Carerras-Sospedra, Marc; Brouwer, Jack; Dabdub, Donald; Lunden, Melissa; Singer, Brett

    2011-07-01

    The effects of liquefied natural gas (LNG) on pollutant emission inventories and air quality in the South Coast Air Basin of California were evaluated using recent LNG emission measurements by Lawrence Berkeley National Laboratory and the Southern California Gas Company (SoCalGas), and with a state-of-the-art air quality model. Pollutant emissions can be affected by LNG owing to differences in composition and physical properties, including the Wobbe index, a measure of energy delivery rate. This analysis uses LNG distribution scenarios developed by modeling Southern California gas flows, including supplies from the LNG receiving terminal in Baja California, Mexico. Based on these scenarios, the projected penetratino of LNG in the South Coast Air Basin is expected to be limited. In addition, the increased Wobbe index of delivered gas (resulting from mixtures of LNG and conventional gas supplies) is expected to cause increases smaller than 0.05 percent in overall (area-wide) emissions of nitrogen oxides (NOx). BAsed on the photochemical state of the South Coast Air Basin, any increase in NOx is expected to cause an increase in the highest local ozone concentrations, and this is reflected in model results. However, the magnitude of the increase is well below the generally accepted accuracy of the model and would not be discernible with the existing monitoring network. Modeling of hypothetical scenarios indicates that discernible changes to ambient ozone and particulate matter concentrations would occur only at LNG distribution rates that are not achievable with current or planned infrastructure and with Wobbe index vlaues that exceed current gas quality tariffs. Results of these hypothetical scenarios are presented for consideration of any proposed substantial expansion of LNG supply infrastructure in Southern California.

  4. Fundamentals of air pollution. Third edition

    Energy Technology Data Exchange (ETDEWEB)

    Boubel, R.W.; Fox, D.L.; Turner, D.B.; Stern, A.C.

    1994-12-31

    This book presents an overview of air pollution. In Part I, the history of air pollution and the basic concepts involved with air pollution such as sources, scales, definitions are covered. Part II describes how airborne pollutants damage materials, vegetation, animals, and humans. Six fundamental aspects of air pollution are included in the text: The Elements of Air Pollution; The Effects of Air Pollution; Measurement and Monitoring of Air Pollution; Meterology of Air Pollution; regulatory Control of Air Pollution; and Engineering Control of Air Pollution.

  5. Reduced bleed air extraction for DC-10 cabin air conditioning

    Science.gov (United States)

    Newman, W. H.; Viele, M. R.; Hrach, F. J.

    1980-01-01

    It is noted that a significant fuel savings can be achieved by reducing bleed air used for cabin air conditioning. Air in the cabin can be recirculated to maintain comfortable ventilation rates but the quality of the air tends to decrease due to entrainment of smoke and odors. Attention is given to a development system designed and fabricated under the NASA Engine Component Improvement Program to define the recirculation limit for the DC-10. It is shown that with the system, a wide range of bleed air reductions and recirculation rates is possible. A goal of 0.8% fuel savings has been achieved which results from a 50% reduction in bleed extraction from the engine.

  6. 14 CFR 298.52 - Air taxi operations by commuter air carriers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Air taxi operations by commuter air... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Commuter Air Carrier Authorizations § 298.52 Air taxi operations by commuter air carriers. (a) A...

  7. Health and air quality 2005 : phase 2 : valuation of health impacts from air quality in the Lower Fraser Valley airshed

    Energy Technology Data Exchange (ETDEWEB)

    Furberg, M.; Preston, K. [RWDI West Inc., Vancouver, BC (Canada); Sawyer, D. [Marbek Resource Consultants Ltd., Ottawa, ON (Canada); Brauer, M. [British Columbia Univ., Vancouver, BC (Canada). School of Occupational and Environmental Hygiene; Hanvelt, R. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Health Care and Epidemiology

    2005-07-15

    This study provided estimates the health benefits and costs associated with specified changes in ambient air concentrations of particulate matter (PM) and ozone in the Lower Fraser Valley (LFV). Estimates were developed on a regional level. The study focused on PM and ozone, as current air quality monitoring data and scientific findings have indicated that these are the air contaminants of greatest concern in the region. Known air quality health outcome relationships were applied in a spreadsheet model to predict changes in health outcomes associated with 6 ambient air quality scenarios for 3 sub-regions within the LFV airshed. Concentration response functions based on epidemiological studies were used to estimate the number of health events associated with changes in air quality. For each scenario, the model calculated the expected number of the following health outcomes: mortality; chronic bronchitis; respiratory hospital admissions; cardiac hospital admissions; emergency room visits; child acute bronchitis; restricted activity days; asthma symptom days; minor restricted activity days and acute respiratory symptom days. The model also produced the dollar value of the health outcomes. A dollar metric was used so that the health outcomes could be aggregated and compared with other air quality management actions such the costs of improving ambient air quality. Results indicated that improving ambient air quality in the LFV will produce valued and socially desirable benefits, including reduced mortality and morbidity. The measures contemplated by decision-makers to maintain and improve air quality in the LFV will trigger benefits that are likely to be significant. 101 refs., 7 tabs., 7 figs.

  8. Aspirated capacitor measurements of air conductivity and ion mobility spectra

    CERN Document Server

    Aplin, K L

    2005-01-01

    Measurements of ions in atmospheric air are used to investigate atmospheric electricity and particulate pollution. Commonly studied ion parameters are (1) air conductivity, related to the total ion number concentration, and (2) the ion mobility spectrum, which varies with atmospheric composition. The physical principles of air ion instrumentation are long-established. A recent development is the computerised aspirated capacitor, which measures ions from (a) the current of charged particles at a sensing electrode, and (b) the rate of charge exchange with an electrode at a known initial potential, relaxing to a lower potential. As the voltage decays, only ions of higher and higher mobility are collected by the central electrode and contribute to the further decay of the voltage. This enables extension of the classical theory to calculate ion mobility spectra by inverting voltage decay time series. In indoor air, ion mobility spectra determined from both the novel voltage decay inversion, and an established volt...

  9. Thin-film silicon for flexible metal-air batteries.

    Science.gov (United States)

    Garamoun, Ahmed; Schubert, Markus B; Werner, Jürgen H

    2014-12-01

    Due to its high energy density, theoretical studies propose silicon as a promising candidate material for metal-air batteries. Herein, for the first time, experimental results detail the use of n-type doped amorphous silicon and silicon carbide as fuel in Si-air batteries. Thin-film silicon is particularly interesting for flexible and rolled batteries with high specific energies. Our Si-air batteries exhibit a specific capacity of 269 Ah kg(-1) and an average cell voltage of 0.85 V at a discharge current density of 7.9 μA cm(-2) , corresponding to a specific energy of 229 Wh kg(-1) . Favorably in terms of safety, low concentrated alkaline solution serves as electrolyte. Discharging of the Si-air cells continues as long as there is silicon available for oxidation. PMID:25251223

  10. Progress in development of flexible metal-air batteries

    Science.gov (United States)

    Sumboja, Afriyanti; Ge, Xiaoming; Zong, Yun; Liu, Zhaolin

    2016-04-01

    Flexible electronics has gained great interest in emerging wearable or rolling-up gadgets, such as foldable displays, electronic papers, and other personal multimedia devices. Subsequently, there is a need to develop energy storage devices that are pliable, inexpensive, and lightweight. Metal-air batteries have been identified as one of alternative energy storages for cost effective and high energy density applications. They offer cheaper production cost and higher energy density than most of the currently available battery technologies. Thus, they are promising candidates for flexible energy storage devices. Flexible metal-air batteries have to maintain their performances during various mechanical deformations. To date, efforts have been focused on fabricating flexible components for metal-air batteries. This review presents a brief introduction to the field, followed by progress on development of flexible electrolytes, electrodes, and prototype devices. Challenges and outlook towards the practical use of metal-air batteries are given in the last part.

  11. Structural Properties of the Brazilian Air Transportation Network.

    Science.gov (United States)

    Couto, Guilherme S; da Silva, Ana Paula Couto; Ruiz, Linnyer B; Benevenuto, Fabrício

    2015-09-01

    The air transportation network in a country has a great impact on the local, national and global economy. In this paper, we analyze the air transportation network in Brazil with complex network features to better understand its characteristics. In our analysis, we built networks composed either by national or by international flights. We also consider the network when both types of flights are put together. Interesting conclusions emerge from our analysis. For instance, Viracopos Airport (Campinas City) is the most central and connected airport on the national flights network. Any operational problem in this airport separates the Brazilian national network into six distinct subnetworks. Moreover, the Brazilian air transportation network exhibits small world characteristics and national connections network follows a power law distribution. Therefore, our analysis sheds light on the current Brazilian air transportation infrastructure, bringing a novel understanding that may help face the recent fast growth in the usage of the Brazilian transport network. PMID:26312421

  12. Measurement of oxygen transfer from air into organic solvents

    DEFF Research Database (Denmark)

    Ramesh, Hemalata; Mayr, Torsten; Hobisch, Mathias;

    2016-01-01

    biological reactions require the supply of oxygen, most normally from air. However, reliable on-line measurements of oxygen concentration in organic solvents (and hence oxygen transfer rates from air to the solvent) has to date proven impossible due limitations in the current analytical methods. Results For...... the first time, we demonstrate on-line oxygen measurements in non-aqueous media using a novel optical sensor. The sensor was used to measure oxygen concentration in various organic solvents including toluene, THF, isooctane, DMF, heptane and hexane (which have all been shown suitable for several...... biological applications). Subsequently, we measured the oxygen transfer rates from air into these organic solvents. Conclusion The measurement of oxygen transfer rates from air into organic solvents using the dynamic method was established using the solvent resistant optical sensor. The feasibility of online...

  13. Ambient air pollution and allergic diseases in children

    Directory of Open Access Journals (Sweden)

    Byoung-Ju Kim

    2012-06-01

    Full Text Available The prevalence of allergic diseases has increased worldwide, a phenomenon that can be largely attributed to environmental effects. Among environmental factors, air pollution due to traffic is thought to be a major threat to childhood health. Residing near busy roadways is associated with increased asthma hospitalization, decreased lung function, and increased prevalence and severity of wheezing and allergic rhinitis. Recently, prospective cohort studies using more accurate measurements of individual exposure to air pollution have been conducted and have provided definitive evidence of the impact of air pollution on allergic diseases. Particulate matter and groundlevel ozone are the most frequent air pollutants that cause harmful effects, and the mechanisms underlying these effects may be related to oxidative stress. The reactive oxidative species produced in response to air pollutants can overwhelm the redox system and damage the cell wall, lipids, proteins, and DNA, leading to airway inflammation and hyper-reactivity. Pollutants may also cause harmful effects via epigenetic mechanisms, which control the expression of genes without changing the DNA sequence itself. These mechanisms are likely to be a target for the prevention of allergies. Further studies are necessary to identify children at risk and understand how these mechanisms regulate gene-environment interactions. This review provides an update of the current understanding on the impact of air pollution on allergic diseases in children and facilitates the integration of issues regarding air pollution and allergies into pediatric practices, with the goal of improving pediatric health.

  14. Humidification dehumidification desalination system using parabolic trough solar air collector

    International Nuclear Information System (INIS)

    This paper deals with a detailed thermodynamic analysis to assess the performance of an HDH system with an integrated parabolic trough solar collector (PTSC). The HDH system considered is an open air, open water, air heated system that uses a PTSC as an air heater. Two different configurations were considered of the HDH system. In the first configuration, the solar air heater was placed before the humidifier whereas in the second configuration the solar air heater was placed between the humidifier and the dehumidifier. The current study revealed that PTSCs are well suited for air heated HDH systems for high radiation location, such as Dhahran, Saudi Arabia. The comparison between the two HDH configurations demonstrates that the gained output ratio (GOR) of the first configuration is, on average, about 1.5 whereas for the second configuration the GOR increases up to an average value of 4.7. The study demonstrates that the HDH configuration with the air heater placed between the humidifier and the dehumidifier has a better performance and a higher productivity. - Highlights: • Thermodynamic analysis of an HDH system driven by a parabolic trough solar collector was conducted. • The first configuration reveals a GOR of 1.5 while the second configuration reveals a GOR of 4.7. • Effective heating of the HDH system was obtained through parabolic trough solar collector

  15. The implementation challenge of urban air quality

    Energy Technology Data Exchange (ETDEWEB)

    Lint, R.J.T. van; Buitenkamp, S.; Zebregs, M. [Ministry of Housing, The Hague (Netherlands). Air Quality and Acidification Abatement Div.

    1995-12-31

    In recent years, the policy followed has booked some significant successes in the structural reduction of the emissions by a number of air polluting substances (e.g. sulphur dioxide and lead). However, the Third Environmental Outlook 1993-2015 has determined that the policy goals for a number of other air polluting substances will not be achieved, particularly in urban areas. This concerns fine dust (PM-10) and polycyclic aromatic hydrocarbons (PAHs), nitrogen dioxide, benzene and black smoke. The policy goals for the above priority substances have been set so as to protect the population against the negative effects on health from too high concentrations of these substances. Forty-six per cent of the Dutch population live in cities of more than 100,000 inhabitants, and, hence, many people are exposed to (too) high concentrations. For this reason, the Netherlands` Second National Environmental Policy Plan lays down that government, provinces and municipalities will together develop a plan of action to reduce urban air pollution to acceptable levels. The formulated strategy is presented in the document here. To that end, the problem analysis and current policy related to the issue are considered in more detail below. On the basis of this, the additional policy strategy is formulated. (author)

  16. Alternative non-CFC mobile air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Mei, V.C.; Chen, F.C.; Kyle, D.M.

    1992-09-01

    Concern about the destruction of the global environment by chlorofluorocarbon (CFC) fluids has become an impetus in the search for alternative, non-CFC refrigerants and cooling methods for mobile air conditioning (MAC). While some alternative refrigerants have been identified, they are not considered a lasting solution because of their high global warming potential, which could result in their eventual phaseout. In view of this dilemma, environmentally acceptable alternative cooling methods have become important. This report, therefore, is aimed mainly at the study of alternative automotive cooling methodologies, although it briefly discusses the current status of alternative refrigerants. The alternative MACs can be divided into work-actuated and heat-actuated systems. Work-actuated systems include conventional MAC, reversed Brayton air cycle, rotary vane compressor air cycle, Stirling cycle, thermoelectric (TE) cooling, etc. Heat-actuated MACs include metal hydride cooling, adsorption cooling, ejector cooling, absorption cycle, etc. While we are better experienced with some work-actuated cycle systems, heat-actuated cycle systems have a high potential for energy savings with possible waste heat applications. In this study, each altemative cooling method is discussed for its advantages and its limits.

  17. A statistical evaluation of asbestos air concentrations

    International Nuclear Information System (INIS)

    Both area and personal air samples collected during an asbestos abatement project were matched and statistically analysed. Among the many parameters studied were fibre concentrations and their variability. Mean values for area and personal samples were 0.005 and 0.024 f cm--3 of air, respectively. Summary values for area and personal samples suggest that exposures are low with no single exposure value exceeding the current OSHA TWA value of 0.1 f cm-3 of air. Within- and between-worker analysis suggests that these data are homogeneous. Comparison of within- and between-worker values suggests that the exposure source and variability for abatement are more related to the process than individual practices. This supports the importance of control measures for abatement. Study results also suggest that area and personal samples are not statistically related, that is, there is no association observed for these two sampling methods when data are analysed by correlation or regression analysis. Personal samples were statistically higher in concentration than area samples. Area sampling cannot be used as a surrogate exposure for asbestos abatement workers. (author)

  18. Green Propulsion Technologies for Advanced Air Transports

    Science.gov (United States)

    Del Rosario, Ruben

    2015-01-01

    Air transportation is critical to U.S. and Global economic vitality. However, energy and climate issues challenge aviations ability to be sustainable in the long term. Aviation must dramatically reduce fuel use and related emissions. Energy costs to U.S. airlines nearly tripled between 1995 and 2011, and continue to be the highest percentage of operating costs. The NASA Advanced Air Transports Technology Project addresses the comprehensive challenge of enabling revolutionary energy efficiency improvements in subsonic transport aircraft combined with dramatic reductions in harmful emissions and perceived noise to facilitate sustained growth of the air transportation system. Advanced technologies and the development of unconventional aircraft systems offer the potential to achieve these improvements. The presentation will highlight the NASA vision of revolutionary systems and propulsion technologies needed to achieve these challenging goals. Specifically, the primary focus is on the N+3 generation; that is, vehicles that are three generations beyond the current state of the art, requiring mature technology solutions in the 2025-30 timeframe, which are envisioned as being powered by Hybrid Electric Propulsion Systems.

  19. Current management of presbyopia

    Directory of Open Access Journals (Sweden)

    Pandelis A Papadopoulos

    2014-01-01

    Full Text Available Presbyopia is a physiologic inevitability that causes gradual loss of accommodation during the fifth decade of life. The correction of presbyopia and the restoration of accommodation are considered the final frontier of refractive surgery. Different approaches on the cornea, the crystalline lens and the sclera are being pursued to achieve surgical correction of this disability. There are however, a number of limitations and considerations that have prevented widespread acceptance of surgical correction for presbyopia. The quality of vision, optical and visual distortions, regression of effect, complications such as corneal ectasia and haze, anisometropia after monovision correction, impaired distance vision and the invasive nature of the currently techniques have limited the utilization of presbyopia surgery. The purpose of this paper is to provide an update of current procedures available for presbyopia correction and their limitations.

  20. The NLM current catalog.

    Science.gov (United States)

    Wiggins, E V

    1969-01-01

    When the National Library of Medicine acquired a computer to augment its publication program, the intent was to present in one medium an index to journal articles and a catalog of books and new serial titles. The computer programs designed for indexing were unsatisfactory for cataloging, however; so two publications were issued, the Index Medicus and the NLM Current Catalog. The Current Catalog features separate name and subject sections, added volumes, and technical reports. The Express Cataloging Service was one of the first attempts to increase the speed and coverage of the Catalog. Shared cataloging with the Library of Congress, the Countway Library at Harvard, and the Upstate Medical Library in Syracuse, New York, have also contributed to the efforts toward improving this library service. An additional shared cataloging program, this time with the National Medical Audiovisual Center, is expected to be implemented shortly. PMID:5782262