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Sample records for alpha continuous air

  1. Alpha-environmental continuous air monitor inlet

    DOEpatents

    Rodgers, John C.

    2003-01-01

    A wind deceleration and protective shroud that provides representative samples of ambient aerosols to an environmental continuous air monitor (ECAM) has a cylindrical enclosure mounted to an input on the continuous air monitor, the cylindrical enclosure having shrouded nozzles located radially about its periphery. Ambient air flows, often along with rainwater flows into the nozzles in a sampling flow generated by a pump in the continuous air monitor. The sampling flow of air creates a cyclonic flow in the enclosure that flows up through the cylindrical enclosure until the flow of air reaches the top of the cylindrical enclosure and then is directed downward to the continuous air monitor. A sloped platform located inside the cylindrical enclosure supports the nozzles and causes any moisture entering through the nozzle to drain out through the nozzles.

  2. Beta/alpha continuous air monitor

    DOEpatents

    Becker, G.K.; Martz, D.E.

    1988-06-27

    A single deep layer silicon detector in combination with a microcomputer, recording both alpha and beta activity and the energy of each pulse, distinquishing energy peaks using a novel curve fitting technique to reduce the natural alpha counts in the energy region where plutonium and other transuranic alpha emitters are present, and using a novel algorithm to strip out radon daughter contribution to actual beta counts. 7 figs.

  3. Beta/alpha continuous air monitor

    DOEpatents

    Becker, Gregory K.; Martz, Dowell E.

    1989-01-01

    A single deep layer silicon detector in combination with a microcomputer, recording both alpha and beta activity and the energy of each pulse, distinguishing energy peaks using a novel curve fitting technique to reduce the natural alpha counts in the energy region where plutonium and other transuranic alpha emitters are present, and using a novel algorithm to strip out radon daughter contribution to actual beta counts.

  4. Sensitivities of five alpha continuous air monitors for detection of airborne sup 239 Pu

    SciTech Connect

    McIsaac, C.V.; Amaro, C.R.

    1992-07-01

    Results of measurements of the sensitivities of five alpha continuous air monitors (CAMs) for detection of airborne {sup 239}Pu are presented. Four commercially available alpha CAMs (Kurz model 8311, Merlin Gerin Edgar, RADeCO model 452, and Victoreen model 758) and a prototype alpha CAM currently in use at Argonne National Laboratory- West (ANL-W) were tested sampling natural ambient air and laboratory-generated atmospheres laden with either blank dust or dust containing nCi/g concentrations of {sup 239}Pu. Cumulative alpha spectra were stored at 30 or 60 minute intervals during each sampling and were subsequently analyzed using three different commonly used alpha spectrum analysis algorithms. The effect of airborne dust concentration and sample filter porosity on detector resolution and sensitivity for airborne {sup 239}Pu are described.

  5. Sensitivities of five alpha continuous air monitors for detection of airborne {sup 239}Pu

    SciTech Connect

    McIsaac, C.V.; Amaro, C.R.

    1992-07-01

    Results of measurements of the sensitivities of five alpha continuous air monitors (CAMs) for detection of airborne {sup 239}Pu are presented. Four commercially available alpha CAMs (Kurz model 8311, Merlin Gerin Edgar, RADeCO model 452, and Victoreen model 758) and a prototype alpha CAM currently in use at Argonne National Laboratory- West (ANL-W) were tested sampling natural ambient air and laboratory-generated atmospheres laden with either blank dust or dust containing nCi/g concentrations of {sup 239}Pu. Cumulative alpha spectra were stored at 30 or 60 minute intervals during each sampling and were subsequently analyzed using three different commonly used alpha spectrum analysis algorithms. The effect of airborne dust concentration and sample filter porosity on detector resolution and sensitivity for airborne {sup 239}Pu are described.

  6. The influence of salt aerosol on alpha radiation detection by WIPP continuous air monitors

    SciTech Connect

    Bartlett, W.T.; Walker, B.A.

    1997-08-01

    Waste Isolation Pilot Plant (WIPP) alpha continuous air monitor (CAM) performance was evaluated to determine if CAMs could detect accidental releases of transuranic radioactivity from the underground repository. Anomalous alpha spectra and poor background subtraction were observed and attributed to salt deposits on the CAM sampling filters. Microscopic examination of salt laden sampling filters revealed that aerosol particles were forming dendritic structures on the surface of the sampling filters. Alpha CAM detection efficiency decreased exponentially as salt deposits increased on the sampling filters, suggesting that sampling-filter salt was performing like a fibrous filter rather than a membrane filter. Aerosol particles appeared to penetrate the sampling-filter salt deposits and alpha particle energy was reduced. These findings indicate that alpha CAMs may not be able to detect acute releases of radioactivity, and consequently CAMs are not used as part of the WIPP dynamic confinement system. 12 refs., 12 figs., 1 tab.

  7. Use of MCNPX for Alpha Spectrometry Simulations of a Continuous Air Monitor

    SciTech Connect

    Robert Hayes, Craig Marianno

    2007-01-01

    The purpose of this study was to determine if the alpha energy spectrum in a Passive Implanted Planar Silicon (PIPS) detector, as modeled by MCNPX [1], can be used to design a radon stripping algorithm for a continuous air monitor (CAM). This stripping algorithm would be employed to discriminate naturally occurring radioisotopes from the anthropogenic for nuclear safety -related applications. It is hoped that using an algorithm based on MCNPX simulations, the CAM will not be prone to false alarms when radon levels are dynamic as identified in other CAM systems [2,3]. This work is focused on the design of the next generation air particulate detector (NGAPD) for the United States Navy. The primary isotope of interest is Co-60. This radionuclide emits a beta with an average energy of 96 keV. Therefore, once deposited on the CAM filter, it will produce a beta continuum seen by the PIPS detector. In addition, as radon progeny is deposited on the air filter, these will give rise to characteristic alpha peaks and a beta continuum. This is primarily an issue in port-or land-based applications. Ultimately, measurement of a radon alpha spectrum is desired to predict the amount of beta activity which would be measured from the radon progeny decay chains. All excess beta activity could then be attributed to anthropogenic sources once the radon progeny contributions have been stripped out.

  8. The influence of salt aerosol on alpha radiation detection by WIPP continuous air monitors

    SciTech Connect

    Bartlett, W.T.; Walker, B.A.

    1996-01-01

    Alpha continuous air monitors (CAMs) will be used at the Waste Isolation Pilot Plant (WIPP) to measure airborne transuranic radioactivity that might be present in air exhaust or in work-place areas. WIPP CAMs are important to health and safety because they are used to alert workers to airborne radioactivity, to actuate air-effluent filtration systems, and to detect airborne radioactivity so that the radioactivity can be confined in a limited area. In 1993, the Environmental Evaluation Group (EEG) reported that CAM operational performance was affected by salt aerosol, and subsequently, the WIPP CAM design and usage were modified. In this report, operational data and current theories on aerosol collection were reviewed to determine CAM quantitative performance limitations. Since 1993, the overall CAM performance appears to have improved, but anomalous alpha spectra are present when sampling-filter salt deposits are at normal to high levels. This report shows that sampling-filter salt deposits directly affect radon-thoron daughter alpha spectra and overall monitor efficiency. Previously it was assumed that aerosol was mechanically collected on the surface of CAM sampling filters, but this review suggests that electrostatic and other particle collection mechanisms are more important than previously thought. The mechanism of sampling-filter particle collection is critical to measurement of acute releases of radioactivity. 41 refs.

  9. A review of acceptance testing of the Los Alamos/Canberra Alpha Sentry Continuous Air Monitor (CAM)

    SciTech Connect

    Rodgers, J.C.

    1998-09-01

    Los Alamos National Laboratory (LANL) undertook the design and development of a new generation of alpha continuous air monitor (CAM) instrumentation that would incorporate advanced technologies in the design of the sampling inlet, multi-channel analyzer (MCA) electronics, solid state alpha detectors, radon background interference suppression, background interference compensation and based on spectral analysis, and microcomputer based data communication, processing, storage, and retrieval. The ANSI air monitoring instrument standards (Performance Specifications for Health Physics Instrumentation -- Occupational Airborne Radioactivity Monitoring Instrumentation, N42.17B) specify performance criteria and testing procedures for instruments and instrument systems designed to continuously sample and quantify airborne radioactivity in the workplace. Although the intent of the standard is to provide performance testing criteria for type testing, it is appropriate to evaluate the performance of a new instrument such as the Alpha Sentry against certain of these criteria for purposes of an acceptance test based on stated specifications and the Los Alamos CAM Requirements document. This report provides an overview of the results of these tests, as they pertain to instruments designed to detect alpha-emitting radionuclides in particulate form.

  10. Effect of prior dust collection on detection, counting efficiency, and energy resolution for alpha continuous air monitors

    SciTech Connect

    Newton, G.J.; Hoover, M.D.

    1994-11-01

    For the past several years, we have supported the DOE Waste Isolation Pilot Plant (WIPP) project by evaluating the capabilities and performance of the Eberline Alpha 6 continuous air monitor (CAM). This evalution has focused on the ability of the CAM to correctly report plutonium in the presence of salt dust. Tests involving the simultaneous collection of plutonium and salt have shown that burial by salt can degrade the detection of plutonium, but that this interference is negligible when salt concentrations are below about 0.2 mg/m{sup 3}. Throughout the evalution, it has been assumed that salt burial is a concern for slow, chronic release of plutonium, but that any acute release of plutonium would be collected on the top surface of the filter or salt and would be unattenuated. The spectral quality of alpha radiation detection on membrane filters is observed to improve with filter loading. This is attributed to the probability that accumulations of dust tend to fill in surface irregularities of the collection filter at a a faster rate than they create additional surface irregularities. The validity of these assumptions about the improved detection of plutonium on salt-layer surfaces has recently been questioned. Based on electron micrographic examination of salt-laden filters, it has been speculated that collection of salt dust on a membrane filter results in formation of pores, fissures, and dendritic shapes of salt on the filter surface. If plutonium were collected, particles could penetrate into the pores and fissures, resulting in a degraded or lost signal from the plutonium. Because no experimental evidence existed to answer the concern, the purpose of the current study was to quantify any differences between detection of plutonium on clean or salt-laden filters.

  11. Influence of dust loading on the alpha-particle energy resolution of continuous air monitors for thin deposits of radioactive aerosols.

    PubMed

    Huang, Suilou; Schery, Stephen D; Alcantara, Raul E; Rodgers, John C; Wasiolek, Piotr T

    2002-12-01

    Alpha-particle continuous air monitors must sometimes be operated in dusty environments where significant dust loading of the filter can be anticipated. It is important to understand how this dust loading affects the response of the continuous air monitors. Not only must a filter be changed if there is a reduction in airflow, but a change may be necessary if the energy resolution deteriorates and the continuous air monitor loses sensitivity and specificity for the radioactive aerosols of interest. A series of experiments were conducted to investigate alpha-particle energy resolution of continuous air monitor filters, particularly under dust loading conditions. Aerosol particles of various sizes were tagged with radon decay products to serve as surrogates for radioactive aerosols of interest such as plutonium or uranium. While the size of radioactive aerosols, filter type, and dust type affected the energy resolution, the thickness of an underlying (nonradioactive) dust layer did not show significant effect for the materials studied and a loading range of 0.01-10 mg x cm(-2). Our results indicate that it is possible for continuous air monitors to detect the release of radioactive aerosols with little deterioration in energy resolution under conditions of significant dust loading provided that the deposited layer of radioactive aerosols remains thin (< or = 0.1 mg x cm(-2)).

  12. Personal continuous air monitor

    DOEpatents

    Morgan, Ronald G.; Salazar, Samuel A.

    2000-01-01

    A personal continuous air monitor capable of giving immediate warning of the presence of radioactivity has a filter/detector head to be worn in the breathing zone of a user, containing a filter mounted adjacent to radiation detectors, and a preamplifier. The filter/detector head is connected to a belt pack to be worn at the waist or on the back of a user. The belt pack contains a signal processor, batteries, a multichannel analyzer, a logic circuit, and an alarm. An air pump also is provided in the belt pack for pulling air through the filter/detector head by way of an air tube.

  13. Improvement in understanding the deposition of ambient dust particles on ECAM (environmental continuous air monitor) filters, reduction of the alpha-particle interference of radon progeny and other radioactive aerosols in different particle size ranges on filters, and development of ECAMs with increased sensitivity under dusty outdoor conditions.

    SciTech Connect

    Schery, Stephen D., Wasiolek, Piotr; Rodgers, John

    1999-06-01

    Improvement in understanding the deposition of ambient dust particles on ECAM (environmental continuous air monitor) filters, reduction of the alpha-particle interference of radon progeny and other radioactive aerosols in different particle size ranges on filters, and development of ECAMs with increased sensitivity under dusty outdoor conditions.

  14. Continuous coherent Lyman- alpha excitation of atomic hydrogen.

    PubMed

    Eikema, K S; Walz, J; Hänsch, T W

    2001-06-18

    The 1S-2P transition in atomic hydrogen has been observed for the first time with almost natural linewidth. We employ a unique source of continuous coherent Lyman- alpha radiation based on four-wave mixing in mercury. The output of the source has been improved 40-fold to yield 20 nW. This demonstration shows that laser cooling and detection with continuous Lyman- alpha radiation has excellent prospects for future experiments with antihydrogen.

  15. Continuous Coherent Lyman-{alpha} Excitation of Atomic Hydrogen

    SciTech Connect

    Eikema, K. S. E.; Walz, J.; Hansch, T. W.

    2001-06-18

    The 1S{minus}2P transition in atomic hydrogen has been observed for the first time with almost natural linewidth. We employ a unique source of continuous coherent Lyman-{alpha} radiation based on four-wave mixing in mercury. The output of the source has been improved 40-fold to yield 20nW. This demonstration shows that laser cooling and detection with continuous Lyman-{alpha} radiation has excellent prospects for future experiments with antihydrogen.

  16. A clean air continuous flow propulsion facility

    NASA Technical Reports Server (NTRS)

    Krauss, R. H.; Mcdaniel, J. C., Jr.

    1992-01-01

    Consideration is given to a contaminant-free, high enthalpy, continuous flow facility designed to obtain detailed code validation measurements of high speed combustion. The facility encompasses uncontaminated air temperature control to within 5 K, fuel temperature control to 2 K, a ceramic flow straightener, drying of inlet air, and steady state continuous operation. The air heating method provides potential for independent control of contaminant level by injection, mixing, and heating upstream. Particular attention is given to extension of current capability of 1250 K total air temperature, which simulates Scramjet enthalpy at Mach 5.

  17. Identification of a major continuous epitope of human alpha crystallin

    NASA Technical Reports Server (NTRS)

    Takemoto, L.; Emmons, T.; Spooner, B. S. (Principal Investigator)

    1992-01-01

    Human lens proteins were digested with trypsin or V8 protease, and the resulting peptides resolved on a C18 reverse phase column. Fractions from this column were probed with polyclonal antiserum made against the whole alpha crystallin molecule. Peptides in the seropositive fraction were purified to homogeneity, then characterized by mass spectral analysis and partial Edman degradation. The tryptic and V8 digests contained only one seropositive peptide that was derived from the C-terminal region of the alpha-A molecule. To determine the exact boundaries of the epitope, various size analogues of this region were synthesized and probed with anti-alpha serum. Together, these studies demonstrate that the major continuous epitope of the alpha-A chain includes the sequence KPTSAPS, corresponding to residues 166-172 of the human alpha-A crystallin chain.

  18. Standoff alpha radiation detection via excited state absorption of air

    SciTech Connect

    Yao, Jimmy; Yin, Stuart Shizhuo; Brenizer, Jack; Hui, Rongqing

    2013-06-24

    A standoff alpha radiation detection technique based on the physical mechanism of excited state absorption of air molecules was explored and is presented in this paper. Instead of directly detecting the radiation via measuring the intensity of radiation induced air fluorescence, the radiation is detected via the excited state absorption of alpha radiation excited/ionized air molecules. Both theoretical analyses and experimental verifications were conducted. The experimental results confirmed that the radiation could be detected via excited state absorption of radiation excited/ionized air molecules at a 10 m standoff distance, which was consistent with the theoretical analyses.

  19. Alpha migration through air filters: A numerical simulation

    NASA Astrophysics Data System (ADS)

    Biermann, Arthur H.; Daroza, Robert A.; Chang, Yun

    1991-12-01

    This theoretical study investigates the migration of alpha-emitting particles through high-efficiency particulate air (HEPA) filters. As part of the study, a review of previous research relating to the alpha-migration phenomena was conducted. As a result of the literature review, a numerical model was developed to simulate the migration of alpha-emitting radionuclide aerosols through HEPA filters. This model predicts the filter performance with regard to particle penetration. It can be used to better estimate the penetration of alpha radioactive species through filter systems for environmental concerns, to aid in the use of current filter systems, and to design new filter systems.

  20. Continuous air monitoring apparatus and method

    SciTech Connect

    Sides, G.D.; Cates, M.

    1992-01-01

    A continuous air monitoring apparatus utilizes a solid sorbent preconcentrator to concentrate airborne sorbent compounds to gas chromatographic analysis. Direct connection between the preconcentrator and gas chromatographic column allows direct desorption of the compounds into the column with minimal dead space. Temperature control on the column allows sharp chromatographic peaks to be attained without cryogenic focusing.

  1. Direct analysis of air filter samples for alpha emitting isotopes

    SciTech Connect

    Mohagheghi, A.H.; Ghanbari, F.; Ebara, S.B.; Enghauser, M.E.; Bakhtiar, S.N.

    1997-04-01

    The traditional method for determination of alpha emitting isotopes on air filters has been to process the samples by radiochemical methods. However, this method is too slow for cases of incidents involving radioactive materials where the determination of personnel received dose is urgent. A method is developed to directly analyze the air filters taken from personal and area air monitors. The site knowledge is used in combination with alpha spectral information to identify isotopes. A mathematical function is developed to estimate the activity for each isotope. The strengths and weaknesses of the method are discussed.

  2. Continuous air monitor filter changeout apparatus

    DOEpatents

    Rodgers, John C.

    2008-07-15

    An apparatus and corresponding method for automatically changing out a filter cartridge in a continuous air monitor. The apparatus includes: a first container sized to hold filter cartridge replacements; a second container sized to hold used filter cartridges; a transport insert connectively attached to the first and second containers; a shuttle block, sized to hold the filter cartridges that is located within the transport insert; a transport driver mechanism means used to supply a motive force to move the shuttle block within the transport insert; and, a control means for operating the transport driver mechanism.

  3. Dynamic Radioactive Source for Evaluating and Demonstrating Time-dependent Performance of Continuous Air Monitors.

    PubMed

    McLean, Thomas D; Moore, Murray E; Justus, Alan L; Hudston, Jonathan A; Barbé, Benoît

    2016-11-01

    Evaluation of continuous air monitors in the presence of a plutonium aerosol is time intensive, expensive, and requires a specialized facility. The Radiation Protection Services Group at Los Alamos National Laboratory has designed a Dynamic Radioactive Source, intended to replace plutonium aerosol challenge testing. The Dynamic Radioactive Source is small enough to be inserted into the sampler filter chamber of a typical continuous air monitor. Time-dependent radioactivity is introduced from electroplated sources for real-time testing of a continuous air monitor where a mechanical wristwatch motor rotates a mask above an alpha-emitting electroplated disk source. The mask is attached to the watch's minute hand, and as it rotates, more of the underlying source is revealed. The measured alpha activity increases with time, simulating the arrival of airborne radioactive particulates at the air sampler inlet. The Dynamic Radioactive Source allows the temporal behavior of puff and chronic release conditions to be mimicked without the need for radioactive aerosols. The new system is configurable to different continuous air monitor designs and provides an in-house testing capability (benchtop compatible). It is a repeatable and reusable system and does not contaminate the tested air monitor. Test benefits include direct user control, realistic (plutonium) aerosol spectra, and iterative development of continuous air monitor alarm algorithms. Data obtained using the Dynamic Radioactive Source has been used to elucidate alarm algorithms and to compare the response time of two commercial continuous air monitors. PMID:27682903

  4. Continuous Air Monitor Operating Experience Review

    SciTech Connect

    L. C. Cadwallader; S. A. Bruyere

    2008-09-01

    Continuous air monitors (CAMs) are used to sense radioactive particulates in room air of nuclear facilities. CAMs alert personnel of potential inhalation exposures to radionuclides and can also actuate room ventilation isolation for public and environmental protection. This paper presents the results of a CAM operating experience review of the DOE Occurrence Reporting and Processing System (ORPS) database from the past 18 years. Regulations regarding these monitors are briefly reviewed. CAM location selection and operation are briefly discussed. Operating experiences reported by the U.S. Department of Energy and in other literature sources were reviewed to determine the strengths and weaknesses of these monitors. Power losses, human errors, and mechanical issues cause the majority of failures. The average “all modes” failure rate is 2.65E-05/hr. Repair time estimates vary from an average repair time of 9 hours (with spare parts on hand) to 252 hours (without spare parts on hand). These data should support the use of CAMs in any nuclear facility, including the National Ignition Facility and the international ITER experiment.

  5. Mathematical model of an air-filled alpha stirling refrigerator

    NASA Astrophysics Data System (ADS)

    McFarlane, Patrick; Semperlotti, Fabio; Sen, Mihir

    2013-10-01

    This work develops a mathematical model for an alpha Stirling refrigerator with air as the working fluid and will be useful in optimizing the mechanical design of these machines. Two pistons cyclically compress and expand air while moving sinusoidally in separate chambers connected by a regenerator, thus creating a temperature difference across the system. A complete non-linear mathematical model of the machine, including air thermodynamics, and heat transfer from the walls, as well as heat transfer and fluid resistance in the regenerator, is developed. Non-dimensional groups are derived, and the mathematical model is numerically solved. The heat transfer and work are found for both chambers, and the coefficient of performance of each chamber is calculated. Important design parameters are varied and their effect on refrigerator performance determined. This sensitivity analysis, which shows what the significant parameters are, is a useful tool for the design of practical Stirling refrigeration systems.

  6. Comparison of continuous air monitor utilization: A case study

    SciTech Connect

    Rodgers, J.C.; Whicker, J.J.; Voss, J.T.

    1997-08-01

    The Chemical Metallurgy Research (CMR) building has been upgrading to different continuous air monitors (CAMs) over the past several years. During the transition, both the newer and older CAMs were positioned in the rooms for field testing and comparison. On December 19, 1996, an accidental release of plutonium aerosol occurred into a laboratory in the CMR building. The event occurred while the room was unoccupied, and no personnel were exposed from this incident. There were two fixed air samplers (FASs) and three CAMs operating in the room at the time the release occurred, including two of the recently installed Canberra Alpha Sentry CAMs and one older Eberline CAM. The apparent cause of the release was a procedure carried out in the basement involving the replacement of the HEPA filter in the ventilation exhaust of a slot-box in the laboratory. For a short period, the ventilation was disconnected from the slot-box in this room, but not from the chemical hood exhaust on the opposite side of the laboratory. Therefore, a condition was created where backflow could occur out of the slot-box and into the room. Eventually all three CAMs in the room alarmed, and the situation was successfully monitored and brought under control by health physics personnel. Data on CAM performance were logged, and Pu activity collected on CAM and FAS filters were measured. A comparison of the new and old continuous air monitoring programs was performed and many interesting lessons on CAM performance and CAM utilization were learned. Overall, this comparison showed the advantages of remote monitoring, timely spectral information, and concentration measurements resolved in time and space.

  7. A Novel Experiment to Investigate the Attenuation of Alpha Particles in Air

    ERIC Educational Resources Information Center

    Andrews, D. G. H.

    2008-01-01

    A simple student experiment investigating dependence on air pressure of the attenuation of alpha particles in air is described. An equation giving the pressure needed to absorb all alpha particles of a given energy is derived from the Bethe-Bloch formula. Results are presented for the attenuation of alpha particles from americium 241 and radium…

  8. A quantitative method for optimized placement of continuous air monitors.

    PubMed

    Whicker, Jeffrey J; Rodgers, John C; Moxley, John S

    2003-11-01

    Alarming continuous air monitors (CAMs) are a critical component for worker protection in facilities that handle large amounts of hazardous materials. In nuclear facilities, continuous air monitors alarm when levels of airborne radioactive materials exceed alarm thresholds, thus prompting workers to exit the room to reduce inhalation exposures. To maintain a high level of worker protection, continuous air monitors are required to detect radioactive aerosol clouds quickly and with good sensitivity. This requires that there are sufficient numbers of continuous air monitors in a room and that they are well positioned. Yet there are no published methodologies to quantitatively determine the optimal number and placement of continuous air monitors in a room. The goal of this study was to develop and test an approach to quantitatively determine optimal number and placement of continuous air monitors in a room. The method we have developed uses tracer aerosol releases (to simulate accidental releases) and the measurement of the temporal and spatial aspects of the dispersion of the tracer aerosol through the room. The aerosol dispersion data is then analyzed to optimize continuous air monitor utilization based on simulated worker exposure. This method was tested in a room within a Department of Energy operated plutonium facility at the Savannah River Site in South Carolina, U.S. Results from this study show that the value of quantitative airflow and aerosol dispersion studies is significant and that worker protection can be significantly improved while balancing the costs associated with CAM programs.

  9. A continuous sampling air-ICP for metals emission monitoring

    SciTech Connect

    Baldwin, D.P.; Zamzow, D.S.; Eckels, D.E.; Miller, G.P.

    1999-09-19

    An air-inductively coupled plasma (air-ICP) system has been developed for continuous sampling and monitoring of metals as a continuous emission monitor (CEM). The plasma is contained in a metal enclosure to allow reduced-pressure operation. The enclosure and plasma are operated at a pressure slightly less than atmospheric using a Roots blower, so that sample gas is continuously drawn into the plasma. A Teflon sampling chamber, equipped with a sampling pump, is connected to the stack that is to be monitored to isokinetically sample gas from the exhaust line and introduce the sample into the air-ICP. Optical emission from metals in the sampled gas stream is detected and monitored using an acousto-optic tunable filter (AOTF)--echelle spectrometer system. A description of the continuous sampling air-ICP system is given, along with some preliminary laboratory data for continuous monitoring of metals.

  10. Calculating alpha Eigenvalues in a Continuous-Energy Infinite Medium with Monte Carlo

    SciTech Connect

    Betzler, Benjamin R.; Kiedrowski, Brian C.; Brown, Forrest B.; Martin, William R.

    2012-09-04

    The {alpha} eigenvalue has implications for time-dependent problems where the system is sub- or supercritical. We present methods and results from calculating the {alpha}-eigenvalue spectrum for a continuous-energy infinite medium with a simplified Monte Carlo transport code. We formulate the {alpha}-eigenvalue problem, detail the Monte Carlo code physics, and provide verification and results. We have a method for calculating the {alpha}-eigenvalue spectrum in a continuous-energy infinite-medium. The continuous-time Markov process described by the transition rate matrix provides a way of obtaining the {alpha}-eigenvalue spectrum and kinetic modes. These are useful for the approximation of the time dependence of the system.

  11. Solid-state continuous Lyman-alpha source for laser-cooling of antihydrogen

    SciTech Connect

    Walz, Jochen; Beyer, Thomas; Kolbe, Daniel; Markert, Frank; Muellers, Andreas; Scheid, Martin

    2008-08-08

    Cooling antihydrogen atoms is important for future experiments both to test the fundamental CPT symmetry by high-resolution laser spectroscopy and also to measure the gravitational acceleration of antimatter. Laser-cooling of antihydrogen can be done on the strong 1 S-2 P transition at the wavelength of Lyman-alpha (121.6 nm). Ongoing work to set up a solid-state continuous-wave laser source at Lyman-alpha is described.

  12. Early and continuing effects of combined alpha and beta irradiation of the lung:

    SciTech Connect

    Scott, B.R.; Hahn, F.F.; Snipes, M.B.; Newton, G.J.; Eidson, A.F.; Mauderly, J.L.; Boecker, B.B.

    1988-03-01

    This report summarizes an inhalation exposure experiment that concerns early and continuing effects of combined alpha and beta irradiation of the lung of rats. Both morbidity at 18 months and mortality within 18 months after exposure were examined for rats exposed to the beta-emitter /sup 147/Pm, the alpha-emitter /sup 238/Pu, or both combined. The results were used to validate hazard-function models that were developed (1)for pulmonary functional morbidity at 18 months and (2) for lethality from radiation pneumonitis and pulmonary fibrosis within 18 months. Both models were found to adequately predict the experimental observations after combined chronic alpha and beta irradiation of the lung. A relative biological effectiveness of approximately 7 was obtained for /sup 238/Pu alpha radiation compared to /sup 147/Pm beta radiation for both pulmonary functional morbidity and lethality from radiation pneumonitis and pulmonary fibrosis. 12 refs., 16 figs., 11 tabs.

  13. Determination of human EEG alpha entrainment ERD/ERS using the continuous complex wavelet transform

    NASA Astrophysics Data System (ADS)

    Chorlian, David B.; Porjesz, Bernice; Begleiter, Henri

    2003-04-01

    Alpha entrainment caused by exposure to a background stimulus continuously flickering at a rate of 8 1/3 Hz was affected by the appearance of a foreground target stimulus to which the subjects were requested to press a button. With the use of bipolar derivations (to reduce volume conduction effects), scalp recorded EEG potentials were subjected to a continuous wavelet transform using complex Morlet wavelets at a range of scales. Complex Morlet wavelets were used to calculate efficiently instantaneous amplitudes and phases on a per-trial basis, rather than using the Hilbert transform on band-pass filtered data. Multiple scales were employed to contrast the pattern of alpha activity with those in other bands, and to determine whether the harmonics observed in the spectral analysis of the data were simply a result of the non-sinusoidal response to the entraining signal or a distinct neural phenomenon. We were thus able to calculate desynchronization/resynchronization for both the entrained and non-entrained alpha activity. The occurance of the target stimulus caused a sharp increase in amplitude in both the entrained and non-entrained alpha activity, followed by a sharp decrease, and then a return to baseline, over a period of 2.5 seconds. However, the entrained alpha activity showed a much more rapid recovery than non-entrained activity.

  14. Continuous air agglomeration method for high carbon fly ash beneficiation

    DOEpatents

    Gray, McMahon L.; Champagne, Kenneth J.; Finseth, Dennis H.

    2000-01-01

    The carbon and mineral components of fly ash are effectively separated by a continuous air agglomeration method, resulting in a substantially carboree mineral stream and a highly concentrated carbon product. The method involves mixing the fly ash comprised of carbon and inorganic mineral matter with a liquid hydrocarbon to form a slurry, contacting the slurry with an aqueous solution, dispersing the hydrocarbon slurry into small droplets within the aqueous solution by mechanical mixing and/or aeration, concentrating the inorganic mineral matter in the aqueous solution, agglomerating the carbon and hydrocarbon in the form of droplets, collecting the droplets, separating the hydrocarbon from the concentrated carbon product, and recycling the hydrocarbon.

  15. Thermal effects on bacterial bioaerosols in continuous air flow.

    PubMed

    Jung, Jae Hee; Lee, Jung Eun; Kim, Sang Soo

    2009-08-01

    Exposure to bacterial bioaerosols can have adverse effects on health, such as infectious diseases, acute toxic effects, and allergies. The search for ways of preventing and curing the harmful effects of bacterial bioaerosols has created a strong demand for the study and development of an efficient method of controlling bioaerosols. We investigated the thermal effects on bacterial bioaerosols of Escherichia coli and Bacillus subtilis by using a thermal electric heating system in continuous air flow. The bacterial bioaerosols were exposed to a surrounding temperature that ranged from 20 degrees C to 700 degrees C for about 0.3 s. Both E. coli and B. subtilis vegetative cells were rendered more than 99.9% inactive at 160 degrees C and 350 degrees C of wall temperature of the quartz tube, respectively. Although the data on bacterial injury showed that the bacteria tended to sustain greater damage as the surrounding temperature increased, Gram-negative E. coli was highly sensitive to structural injury but Gram-positive B. subtilis was slightly more sensitive to metabolic injury. In addition, the inactivation of E. coli endotoxins was found to range from 9.2% (at 200 degrees C) to 82.0% (at 700 degrees C). However, the particle size distribution and morphology of both bacterial bioaerosols were maintained, despite exposure to a surrounding temperature of 700 degrees C. Our results show that thermal heating in a continuous air flow can be used with short exposure time to control bacterial bioaerosols by rendering the bacteria and endotoxins to a large extent inactive. This result could also be useful for developing more effective thermal treatment strategies for use in air purification or sterilization systems to control bioaerosols.

  16. Continuous infusion of 5-fluorouracil with alpha 2b interferon for advanced colorectal carcinoma.

    PubMed Central

    Ferguson, J. E.; Hulse, P.; Lorigan, P.; Jayson, G.; Scarffe, J. H.

    1995-01-01

    Thirty patients with symptomatic colorectal carcinoma were commenced on treatment with 5-fluorouracil (2.5 g week-1) administered by continuous intravenous infusion and alpha 2b interferon (3 x 10(6) U s.c. three times a week). Six out of 30 patients (20%) achieved a partial response. Three patients (10%) had stable disease and 21 patients (70%) progressed on treatment. Twenty patients (67%) completed ten or more weeks of treatment. In nine patients, treatment was withdrawn after 2-9 weeks because of disease progression or death. One patient's treatment was interrupted by emergency surgery. The median survival for all patients was 210 days (7 months). The principal side-effects were oral mucositis (12/30 patients), nausea (8/30 patients) and transient diarrhoea (4/30 patients), and initial constitutional symptoms due to alpha 2b interferon. The combination of low-dose continuous infusional 5-fluorouracil and low-dose alpha 2b interferon is well tolerated but has no obvious advantage over alternative infusional regimens using 5-fluorouracil as a single agent. PMID:7599051

  17. The influence of nitrogen sources on the alpha-amylase productivity of Aspergillus oryzae in continuous cultures.

    PubMed

    Pedersen, H; Nielsen, J

    2000-03-01

    The influence of the nitrogen source on the alpha-amylase productivity of Aspergillus oryzae was quantified in continuous cultivations. Both inorganic and complex nitrogen sources were investigated and glucose was used as the carbon and energy sources. For production of alpha-amylase, nitrate was shown to be inferior to ammonia as a nitrogen source. A mixture of ammonia and complex nitrogen sources, such as yeast extract or casein hydrolysate, was better than with ammonia as the sole nitrogen source. Even a low concentration of casein hydrolysate (0.05 g l(-1)) resulted in a 35% increase in the alpha-amylase productivity. The higher alpha-amylase productivity during growth on casein hydrolysate was not caused by increased transcription of the alpha-amylase genes but was caused by a faster secretion of alpha-amylase or by a lower binding of alpha-amylase to the biomass.

  18. The TOMPs ambient air monitoring network - Continuous data on UK air quality for over 20 years.

    PubMed

    Graf, Carola; Katsoyiannis, Athanasios; Jones, Kevin C; Sweetman, Andrew J

    2016-10-01

    Long-term air monitoring datasets are needed for persistent organic pollutants (POPs) to assess the effectiveness of source abatement measures and the factors controlling ambient levels. The Toxic Organic Micro Pollutants (TOMPs) Network, which has operated since 1991, collects ambient air samples at six sites across England and Scotland, using high-volume active air samplers. The network provides long-term ambient air trend data for a range of POPs at both urban and rural locations. Data from the network provides the UK Government, regulators and researchers with valuable information on emission/source controls and on the effectiveness of international chemicals regulation such as the Stockholm Convention and UN/ECE Protocol on POPs. The target chemicals of TOMPs have been polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and, since 2010, polybrominated diphenyl ethers (PBDEs). The continuous monitoring of these compounds demonstrates the constant decline in UK air concentrations over the last two decades, with average clearance rates for PCDD/Fs in urban locations of 5.1 years and for PCBs across all sites 6.6 years. No significant declines in rural locations for PCDD/Fs have been observed. There is a strong observable link between the declining ambient air concentrations and the emission reductions estimated in the annually produced National Atmospheric Emission Inventory (NAEI) dataset. These findings clearly demonstrate the unique strengths of long-term consistent datasets for the evaluation of the success of chemical regulation and control.

  19. Gross Alpha Beta Radioactivity in Air Filters Measured by Ultra Low Level α/β Counter

    NASA Astrophysics Data System (ADS)

    Cfarku, Florinda; Bylyku, Elida; Deda, Antoneta; Dhoqina, Polikron; Bakiu, Erjona; Perpunja, Flamur

    2010-01-01

    Study of radioactivity in air as very important for life is done regularly using different methods in every country. As a result of nuclear reactors, atomic centrals, institutions and laboratories, which use the radioactivity substances in open or closed sources, there are a lot radioactive wastes. Mixing of these wastes after treatment with rivers and lakes waters makes very important control of radioactivity. At the other side nuclear and radiological accidents are another source of the contamination of air and water. Due to their radio toxicity, especially those of Sr90, Pu239, etc. a contamination hazard for human begins exist even at low concentration levels. Measurements of radioactivity in air have been performed in many parts of the world mostly for assessment of the doses and risk resulting from consuming air. In this study we present the results of international comparison organized by IAEA Vienna, Austria for the air filters spiked with unknown Alpha and Beta Activity. For the calibration of system we used the same filters spiked: a) with Pu-239 as alpha source; b) Sr-90 as beta source and also the blank filter. The measurements of air filter samples after calibration of the system are done with Ultra Low Level α/β Counter (MPC 9604) Protean Instrument Corporation. The high sensitivity of the system for the determination of the Gross Alpha and Beta activity makes sure detection of low values activity of air filters. Our laboratory results are: Aα = (0.19±0.01) Bq/filter and Aα (IAEA) = (0.17±0.009) Bq/filter; Aβ = (0.33±0.009) Bq/filter and Aβ (IAEA) = (0.29±0.01) Bq/filter. As it seems our results are in good agreement with reference values given by IAEA (International Atomic Energy Agency).

  20. Continuous hydrogen production during fermentation of alpha-cellulose by the thermophillic bacterium Clostridium thermocellum.

    PubMed

    Magnusson, Lauren; Cicek, Nazim; Sparling, Richard; Levin, David

    2009-02-15

    Continuous hydrogen (H2) production during fermentation of alpha-cellulose was established using the thermophillic, anaerobic bacterium Clostridium thermocellum ATCC 27405. The objectives of this work were to characterize growth of C. thermocellum, quantify H2 production and determine soluble end-product synthesis patterns during fermentation of a cellulosic substrate under continuous culture conditions. A 5 L working volume fermentor was established and growth experiments were maintained for over 3,000 h. Substrate concentrations were varied from 1 to 4 g/L and the feed was introduced with continuous nitrogen gas sparging to prevent clogging of the feed-line. The pH and temperature of the reactor were maintained at 7.0 and 600 degrees C, respectively, throughout the study. At concentrations above 4 g/L, the delivery of alpha-cellulose was impaired due to feed-line clogging and it became difficult to maintain a homogenous suspension. The highest total gas (H2 plus CO2) production rate, 56.6 mL L(-1) h(-1), was observed at a dilution rate of 0.042 h(-1) and substrate concentration of 4 g/L. Under these conditions, the H2 production rate was 5.06 mmol h(-1). Acetate and ethanol were the major soluble end-products, while lactate and formate were greatly reduced compared to production in batch cultures. Concentrations of all metabolites increased with increasing substrate concentration, with the exception of lactate. Despite a number of short-term electrical and mechanical failures during the testing period, the system recovered quickly, exhibiting substantial robustness. A carbon balance was completed to ensure that all end-products were accounted for, with final results indicating near 100% carbon recovery. This study shows that long-term, stable H2 production can be achieved during direct fermentation of an insoluble cellulosic substrate under continuous culture conditions.

  1. An experimental quantification of the NOX production efficiency of energetic alpha particles in air

    NASA Astrophysics Data System (ADS)

    Rahman, Mahbubur; Cooray, Vernon; Possnert, Göran; Nyberg, Johan

    2006-07-01

    An experimental study on the production of NOX by alpha particles impact in air at atmospheric pressure is presented. A mixed radioactive source of 208Po and 209Po with an integrated activity of 9.6 MBq over a solid angle of 2π and an average alpha particle energy of 4.5 MeV was used for ionization of atmospheric air in an airtight chamber and the NOX production was measured by the chemiluminescence method. The NOX production rate is found to be about 1.2 NOX molecules per ion-pair. The NOX production efficiency per Joule of dissipated energy is calculated to be 20×1016 NOX molecules per Joule. This efficiency is comparable to that of hot laboratory sparks discharges.

  2. 42 CFR 84.148 - Type C supplied-air respirator, continuous flow class; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Type C supplied-air respirator, continuous flow... RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.148 Type C supplied-air respirator, continuous flow class; minimum requirements. (a) Respirators tested under this section shall be approved only...

  3. Continuous air monitor correlation to fixed air sample data at Los Alamos National Laboratory

    SciTech Connect

    Whicker, J.J.

    1993-05-01

    Continuous air monitoring instruments (CAMS) deployed in laboratories in the TA-55 plutonium facility at Los Alamos National Laboratory (LANL) alarmed less than 33 percent of the time when fixed air sample measurements in the same laboratory showed integrated concentrations exceeding 500 DAC-hrs. The purpose of this study was to explore effects of non-instrument variables on alarm sensitivities for properly working CAMS. Non-instrument variables include air flow patterns, particle size of released material, and the energy of the release. Dilution Factors (DFs) for 21 airborne releases in various rooms and of different magnitudes were calculated and compared. The median DF for releases where the CAM alarmed was 13.1 while the median DF for releases where the CAM did not alarm was 179. Particle sizes ranged considerably with many particles larger than 10 {mu}m. The cause of the release was found to be important in predicting if a CAM would alarm with releases from bagouts resulting in the greatest percentage of CAM alarms. The results of this study suggest that a two-component strategy for CAM placement at LANL be utilized. The first component would require CAMs at exhaust points in the rooms to provide for reliable detection for random release locations. The second component would require placing CAMs at locations where releases have historically been seen. Finally, improvements in CAM instrumentation is needed.

  4. Comparison of Ambient Radon Concentrations in Air in the Northern Mojave Desert from Continuous and Integrating Instruments

    SciTech Connect

    David S. Shafer; David McGraw; Lynn H. Karr; Greg McCurdy; Tammy L. Kluesner; Karen J. Gray; Jeffrey Tappen

    2010-05-18

    As part of a program to characterize and baseline environmental parameters, ambient radon-222 (Rn) monitoring was conducted in the rural community of Amargosa Valley, NV, the closest community to Yucca Mountain. Passive integrating and continuous Rn monitoring instruments were deployed adjacent to the Community Environmental Monitoring Program (CEMP) station in Amargosa Valley. The CEMP station provided real-time ambient gamma exposure and meteorological data used to correct the integrated Rn measurements, verified the meteorological data collected by the continuous Rn monitoring instrument, and for provided instrumentation for evaluating the relationships between meteorological conditions and Rn concentrations. Hourly Rn concentrations in air measured by the continuous Rn monitoring instrument (AlphaGUARD®) were compared to the average hourly values for the integrating Rn measurements (E-PERM®) by dividing the total Rn measurements by the number of hours the instruments were deployed. The results of the comparison indicated that average hourly ambient Rn concentrations as measured by both methods ranged from 0.2 to 0.4 pico-curies per liter of air. Ambient Rn values for the AlphaGUARD exhibited diurnal variations. When Rn concentrations were compared with measurements of temperature (T), barometric pressure, and relative humidity, the correlation (inversely) was highest with T, albeit weakly.

  5. Alpha image reconstruction (AIR): A new iterative CT image reconstruction approach using voxel-wise alpha blending

    SciTech Connect

    Hofmann, Christian; Sawall, Stefan; Knaup, Michael; Kachelrieß, Marc

    2014-06-15

    Purpose: Iterative image reconstruction gains more and more interest in clinical routine, as it promises to reduce image noise (and thereby patient dose), to reduce artifacts, or to improve spatial resolution. Among vendors and researchers, however, there is no consensus of how to best achieve these aims. The general approach is to incorporatea priori knowledge into iterative image reconstruction, for example, by adding additional constraints to the cost function, which penalize variations between neighboring voxels. However, this approach to regularization in general poses a resolution noise trade-off because the stronger the regularization, and thus the noise reduction, the stronger the loss of spatial resolution and thus loss of anatomical detail. The authors propose a method which tries to improve this trade-off. The proposed reconstruction algorithm is called alpha image reconstruction (AIR). One starts with generating basis images, which emphasize certain desired image properties, like high resolution or low noise. The AIR algorithm reconstructs voxel-specific weighting coefficients that are applied to combine the basis images. By combining the desired properties of each basis image, one can generate an image with lower noise and maintained high contrast resolution thus improving the resolution noise trade-off. Methods: All simulations and reconstructions are performed in native fan-beam geometry. A water phantom with resolution bar patterns and low contrast disks is simulated. A filtered backprojection (FBP) reconstruction with a Ram-Lak kernel is used as a reference reconstruction. The results of AIR are compared against the FBP results and against a penalized weighted least squares reconstruction which uses total variation as regularization. The simulations are based on the geometry of the Siemens Somatom Definition Flash scanner. To quantitatively assess image quality, the authors analyze line profiles through resolution patterns to define a contrast

  6. Alpha power and coherence primarily reflect neural activity related to stages of motor response during a continuous monitoring task.

    PubMed

    Moore, Roger A; Gale, Anthony; Morris, Paul H; Forrester, Dave

    2008-08-01

    Previously, EEG theta (4-6 Hz) was related to goal conflict resolution [Moore, R.A., Gale, A., Morris, P.H., Forrester, D., 2006. Theta phase locking across the neocortex reflects cortico-hippocampal recursive communication during goal conflict resolution. Int. J. Psychophysiol. 60, 260-273] in the context of theory linked with animal hippocampal theta [Gray, J.A., McNaughton, N., 2000. The Neuropsychology of Anxiety: An Enquiry into the Functions of the Septo-Hippocampal system, 2nd ed, Oxford University Press, Oxford]. Here, the hypothesis that human EEG alpha (8-12 Hz) may also be a natural analogue to animal hippocampal theta is tested. Participants engaged in a monitoring task where the object was to press a response key immediately after presentation of 4 individual, non-repeating, single integer odd digits. These were presented amongst a continuous stream of single integer digits and Xs. EEG recorded in the earlier study were reanalysed; this time extracting alpha power and coherence from the same 34 participants. Alpha had a different profile to theta and was not primarily related to goal conflict. Low alpha (8-10 Hz) coherence consistently increased at electrodes close to primary sensorimotor cortex; particularly during response execution and response inhibition. The coherence analysis revealed that high alpha (10-12 Hz) related to response execution. Supplementary analyses demonstrated widespread high alpha coherence increase during response execution, inhibition and preparation. These data were discussed within the context of motor driven 'classic alpha' and Rolandic mu. A coherence profile which differentiated response execution and response inhibition was proposed to reflect a working memory network which was activated during response execution. Also, alpha power (8-12 Hz) reduced at several central electrodes during response execution. This reflected classic Rolandic mu response. Participants displaying a predicted low alpha power trend had the

  7. Continuous Quantitative Measurements on a Linear Air Track

    ERIC Educational Resources Information Center

    Vogel, Eric

    1973-01-01

    Describes the construction and operational procedures of a spark-timing apparatus which is designed to record the back and forth motion of one or two carts on linear air tracks. Applications to measurements of velocity, acceleration, simple harmonic motion, and collision problems are illustrated. (CC)

  8. Hexachlorocyclohexanes (HCHs) in the Canadian Archipelago. 2. Air-water gas exchange of alpha- and gamma-HCH.

    PubMed

    Jantunen, Liisa M; Helm, Paul A; Kylin, Henrik; Bidleman, Terry F

    2008-01-15

    Air and water were sampled in the Canadian Archipelago during summer on the Tundra Northwest 1999 (TNW-99) expedition and air was sampled at Resolute Bay (RB), Nunavut, to determine the gas exchange of alpha- and gamma-hexachlorocyclohexanes (HCHs) and the enantiomers of alpha-HCH. Air concentrations of sigmaHCH during TNW-99 and at RB were similar, averaging 55 and 53 pg m(-3), respectively. The net gas exchange direction was volatilization for alpha-HCH and near equilibrium or deposition for gamma-HCH, whereas actual fluxes depended on the fraction of open water. Enantiomer fractions, EF = (+)/[(+) + (-)] of alpha-HCH in air sampled from shipboard were significantly correlated to those in surface water for events with >90% open water, but were closer to racemic and not correlated to EFs in water for events with 0-50% open water. Levels of alpha-HCH in air at RB averaged 37 +/- 9 pg m(-3) from June to early July, and EFs were close to racemic (0.496 +/- 0.004). In mid-July the ice pack broke up around RB. From this point through August, air concentrations increased significantly to 53 +/- 5 pg m(-3), and the mean EF decreased significantly to 0.483 +/- 0.009. Air concentrations of gamma-HCH at RB did not differ significantly before (8.0 +/- 3.7 pg m(-3)) and after (6.6 +/- 0.76 pg m(-3)) ice breakup. Results show that alpha-HCH enantiomers are sensitive tracers for following the impact of ice cover loss on gas exchange in the Arctic.

  9. Influence of environmental factors and air composition on the emission of {alpha}-pinene from Quercus ilex leaves

    SciTech Connect

    Loreto, F.; Tricoli, D.; Ciccioli, P.

    1996-01-01

    We studied the emission of {alpha}-pinene from Quercus ilex leaves. Only the abaxial side of the hypostomatous Q. ilex leaf emits {alpha}-pinene. Light induced photosynthesis and {alpha}-pinene emission. However, the response of photosynthesis to dark-to-light transitions was faster than that of {alpha}-pinene, suggesting that ATP controls the emission. The emission was higher at 30 than at 20{degrees}C, whereas photosynthesis did not change. Therefore, the relationship between photosynthesis and {alpha}-pinene emission does not always hold. When CO{sub 2} was removed from the air, transpiration was stimulated and transpiration was reduced, but {alpha}-pinene emission was unaffected. Therefore, the emission depends on the availability of photosynthetic carbon, is not saturated at ambient CO{sub 2}, and is not dependent on stomatal opening. The pattern of {alpha}-pinene emission from Q. ilex is different from that of plants having specialized structures for storage and emission of terpenes. We suggest that {alpha}-pinene emitted by Q. ilex leaves is synthesized in the chloroplasts and shares the same biochemical pathway with isoprene emitted by isoprene-emitting oak species. 28 refs., 8 figs., 1 tab.

  10. Indicator providing continuous indication of the presence of a specific pollutant in air

    NASA Technical Reports Server (NTRS)

    Miller, C. G.; Bartera, R. E. (Inventor)

    1976-01-01

    A continuous HCl in-air indicator was developed which consists of a tube-like element with an inlet end through which a continuous stream of air containing HCl enters. The air flows downstream from the inlet end and exits the element's outlet end. Positioned between the element's inlet and outlet ends are first and second spaced apart photoelectric units, which are preferably positioned adjacent the inlet and outlet ends, respectively. Ammonia gas is injected into the air, flowing through the element, at a position between the two photoelectric units. The ammonia gas reacts with the HCl in the air to form ammonium chloride particles. The difference between the outputs of the two photoelectric units is an indication of the amount of HCl in the air stream.

  11. Field estimates of polyurethane foam - air partition coefficients for hexachlorobenzene, alpha-hexachlorocyclohexane and bromoanisoles.

    PubMed

    Bidleman, Terry F; Nygren, Olle; Tysklind, Mats

    2016-09-01

    Partition coefficients of gaseous semivolatile organic compounds (SVOCs) between polyurethane foam (PUF) and air (KPA) are needed in the estimation of sampling rates for PUF disk passive air samplers. We determined KPA in field experiments by conducting long-term (24-48 h) air sampling to saturate PUF traps and shorter runs (2-4 h) to measure air concentrations. Sampling events were done at daily mean temperatures ranging from 1.9 to 17.5 °C. Target compounds were hexachlorobenzene (HCB), alpha-hexachlorocyclohexane (α-HCH), 2,4-dibromoanisole (2,4-DiBA) and 2,4,6-tribromoanisole (2,4,6-TriBA). KPA (mL g(-1)) was calculated from quantities on the PUF traps at saturation (ng g(-1)) divided by air concentrations (ng mL(-1)). Enthalpies of PUF-to-air transfer (ΔHPA, kJ mol(-1)) were determined from the slopes of log KPA/mL g(-1) versus 1/T(K) for HCB and the bromoanisoles, KPA of α-HCH was measured only at 14.3 to 17.5 °C and ΔHPA was not determined. Experimental log KPA/mL g(-1) at 15 °C were HCB = 7.37; α-HCH = 8.08; 2,4-DiBA = 7.26 and 2,4,6-TriBA = 7.26. Experimental log KPA/mL g(-1) were compared with predictions based on an octanol-air partition coefficient (log KOA) model (Shoeib and Harner, 2002a) and a polyparameter linear free relationship (pp-LFER) model (Kamprad and Goss, 2007) using different sets of solute parameters. Predicted KP values varied by factors of 3 to over 30, depending on the compound and the model. Such discrepancies provide incentive for experimental measurements of KPA for other SVOCs. PMID:27285381

  12. 42 CFR 84.155 - Airflow resistance test; Type C supplied-air respirator, continuous flow class and Type CE...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... respirator, continuous flow class and Type CE supplied-air respirator; minimum requirements. 84.155 Section... Respirators § 84.155 Airflow resistance test; Type C supplied-air respirator, continuous flow class and Type... shall not exceed 25 mm. (1 inch) of water-column height when the air flow into the...

  13. 42 CFR 84.155 - Airflow resistance test; Type C supplied-air respirator, continuous flow class and Type CE...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Airflow resistance test; Type C supplied-air... Respirators § 84.155 Airflow resistance test; Type C supplied-air respirator, continuous flow class and Type CE supplied-air respirator; minimum requirements. The resistance to air flowing from the...

  14. 42 CFR 84.155 - Airflow resistance test; Type C supplied-air respirator, continuous flow class and Type CE...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Airflow resistance test; Type C supplied-air... Respirators § 84.155 Airflow resistance test; Type C supplied-air respirator, continuous flow class and Type CE supplied-air respirator; minimum requirements. The resistance to air flowing from the...

  15. 42 CFR 84.155 - Airflow resistance test; Type C supplied-air respirator, continuous flow class and Type CE...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Airflow resistance test; Type C supplied-air... Respirators § 84.155 Airflow resistance test; Type C supplied-air respirator, continuous flow class and Type CE supplied-air respirator; minimum requirements. The resistance to air flowing from the...

  16. 42 CFR 84.155 - Airflow resistance test; Type C supplied-air respirator, continuous flow class and Type CE...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Airflow resistance test; Type C supplied-air... Respirators § 84.155 Airflow resistance test; Type C supplied-air respirator, continuous flow class and Type CE supplied-air respirator; minimum requirements. The resistance to air flowing from the...

  17. Investigation of Techniques to Improve Continuous Air Monitors Under Conditions of High Dust Loading in Environmental Settings

    SciTech Connect

    Suilou Huang; Stephen D. Schery; John C. Rodgers

    2002-07-23

    A number of DOE facilities, such as the Los Alamos National Laboratory (LANL) and the Waste Isolation Pilot Plant (WIPP), use alpha-particle environmental continuous air monitors (ECAMs) to monitor air for unwanted releases of radioactive aerosols containing such materials as plutonium and uranium. High sensitivity, ease of operation, and lack of false alarms are all important for ECAMs. The object of the project was to conduct investigations to improve operation of ECAMs, particularly under conditions where a lot of nonradioactive dust may be deposited on the filters (conditions of high dust loading). The presence of such dust may increase the frequency with which filters must be changed and can lead to an increased incidence of false alarms due to deteriorated energy resolution and response specificity to the radionuclides of interest. A major finding of the investigation, not previously documented, was that under many conditions thick layers of underlying nonradioactive dust do not decrease energy resolution and specificity for target radionuclides if the radioactive aerosol arrives as a sudden thin burst deposit, as commonly occurs in the early-warning alarm mode. As a result, operators of ECAMs may not need to change filters as often as previously thought and have data upon which to base more reliable operating procedures.

  18. Activity and tolerance of a continuous subcutaneous infusion of interferon-alpha2b in patients with chronic hepatitis C.

    PubMed

    Schenker, S; Cutler, D; Finch, J; Tamburro, C H; Affrime, M; Sabo, R; Bay, M

    1997-11-01

    We administered interferon-alpha2b (IFN-alpha2b) by continuous subcutaneous infusion (60,000 IU/h, or 10 million IU/week) over 3 months to 7 patients with chronic hepatitis C. All had previously responded, as assessed by normalization of transaminases to the same dose of IFN administered by intermittent injection over 6 months, but had relapsed after cessation of therapy. The continuous infusion was tolerated well at the site of infusion, and the systemic side effects were similar in type but were lesser in intensity than with intermittent dosage. Four of 7 subjects had normalization of transaminase at the end of week 12 of therapy. Serum HCV RNA and HCV by PCR decreased with treatment, and there was a prompt and sustained increase in serum beta2-microglobulin and of 2', 5' OAS activity. The level of the latter appeared to correlate with response of the transaminase. Serum IFN concentrations were low but detectable throughout therapy. After stopping IFN administration, the transaminases in responders increased again to pretreatment levels.

  19. Continuous measurements of ammonia, nitrous oxide and methane from air scrubbers at pig housing facilities.

    PubMed

    Van der Heyden, C; Brusselman, E; Volcke, E I P; Demeyer, P

    2016-10-01

    Ammonia, largely emitted by agriculture, involves a great risk for eutrophication and acidification leading to biodiversity loss. Air scrubbers are widely applied to reduce ammonia emission from pig and poultry housing facilities, but it is not always clear whether their performance meets the requirements. Besides, there is a growing international concern for the livestock related greenhouse gases methane and nitrous oxide but hardly any data concerning their fate in air scrubbers are available. This contribution presents the results from measurement campaigns conducted at a chemical, a biological and a two-stage biological air scrubber installed at pig housing facilities in Flanders. Ammonia, nitrous oxide and methane at the inlet and outlet of the air scrubbers were monitored on-line during one week using a photoacoustic gas monitor, which allowed to investigate diurnal fluctuations in the removal performance of air scrubbers. Additionally, the homogeneity of the air scrubbers, normally checked by gas detection tubes, was investigated in more detail using the continuous data. The biological air scrubber with extra nitrification tank performed well in terms of ammonia removal (86 ± 6%), while the two-stage air scrubber suffered from nitrifying bacteria inhibition. In the chemical air scrubber the pH was not kept constant, lowering the ammonia removal efficiency. A lower ammonia removal efficiency was found during the day, when the ventilation rate was the highest. Nitrous oxide was produced inside the biological and two-stage scrubber, resulting in an increased outlet concentration of more than 200%. Methane could not be removed in the different air scrubbers because of its low water solubility. PMID:27341376

  20. Continuous measurements of ammonia, nitrous oxide and methane from air scrubbers at pig housing facilities.

    PubMed

    Van der Heyden, C; Brusselman, E; Volcke, E I P; Demeyer, P

    2016-10-01

    Ammonia, largely emitted by agriculture, involves a great risk for eutrophication and acidification leading to biodiversity loss. Air scrubbers are widely applied to reduce ammonia emission from pig and poultry housing facilities, but it is not always clear whether their performance meets the requirements. Besides, there is a growing international concern for the livestock related greenhouse gases methane and nitrous oxide but hardly any data concerning their fate in air scrubbers are available. This contribution presents the results from measurement campaigns conducted at a chemical, a biological and a two-stage biological air scrubber installed at pig housing facilities in Flanders. Ammonia, nitrous oxide and methane at the inlet and outlet of the air scrubbers were monitored on-line during one week using a photoacoustic gas monitor, which allowed to investigate diurnal fluctuations in the removal performance of air scrubbers. Additionally, the homogeneity of the air scrubbers, normally checked by gas detection tubes, was investigated in more detail using the continuous data. The biological air scrubber with extra nitrification tank performed well in terms of ammonia removal (86 ± 6%), while the two-stage air scrubber suffered from nitrifying bacteria inhibition. In the chemical air scrubber the pH was not kept constant, lowering the ammonia removal efficiency. A lower ammonia removal efficiency was found during the day, when the ventilation rate was the highest. Nitrous oxide was produced inside the biological and two-stage scrubber, resulting in an increased outlet concentration of more than 200%. Methane could not be removed in the different air scrubbers because of its low water solubility.

  1. Selective central alpha-2 adrenoceptor control of regional haemodynamic responses to air jet stress in conscious spontaneously hypertensive rats.

    PubMed

    Kapusta, D R; Knardahl, S; Koepke, J P; Johnson, A K; DiBona, G F

    1989-03-01

    The role of central nervous system alpha 2-adrenoceptors in the regulation of peripheral sympathetic outflow to regional vascular resistance beds during environmental stress was examined in conscious chronically instrumented spontaneously hypertensive rats (SHR). SHR were instrumented with pulsed Doppler flow probes on the renal and mesenteric arteries and the lower abdominal aorta. The mean arterial pressure (MAP), heart rate and regional vascular resistance responses to air jet stress were determined before and after cumulative administration of the alpha 2-adrenoceptor agonist, guanabenz, into the lateral cerebral ventricle in doses of 5 and 25 micrograms. Compared with intracerebroventricular (i.c.v.) administration of isotonic saline vehicle which did not affect baseline systemic and regional haemodynamic measurements, guanabenz produced significant decreases in baseline MAP and heart rate but did not affect regional vascular resistances. During air jet stress, the characteristic pattern of the classic defense reaction with an increase in MAP, heart rate, renal and mesenteric vascular resistances and a decrease in hindquarters vascular resistance was observed and was not affected by i.c.v. administration of isotonic saline vehicle. Guanabenz did not affect the MAP, heart rate or renal vascular resistance responses to air jet stress. The air jet stress-induced increase in mesenteric vascular resistance was reduced by 25 micrograms guanabenz. The air jet stress-induced decrease in hindquarters vascular resistance was converted to an increase by 25 micrograms guanabenz. These results demonstrate that the regulation of environmental stress-stimulated sympathetic neural outflow to different vascular beds may be independently controlled by central nervous system alpha 2-adrenoceptors.

  2. Continuous matrix assisted refolding of alpha-lactalbumin by ion exchange chromatography with recycling of aggregates combined with ultradiafiltration.

    PubMed

    Machold, Christine; Schlegl, Robert; Buchinger, Wolfgang; Jungbauer, Alois

    2005-07-01

    Continuous matrix assisted refolding (MAR) can be achieved on a solid support by using a continuous chromatographic system. Recycling the aggregate fraction, simultaneously formed during a refolding reaction, can further increase the refolding yield. Due to the nature of this reaction, aggregates are the main reason for a refolding yield below stoichiometric conversion. A preparative continuous annular chromatographic system (P-CAC) equipped with an ion exchange resin was used to continuously refold the model protein alpha-lactalbumin. For this purpose, this protein was denatured, reduced and adsorbed on the ion exchange resin. Elution was performed with or without redox reagents in the buffer system permitting fast formation of the native disulfide bonds. In the case redox reagents were present, the protein refolds then during its residence time on the matrix. However, aggregate formation is also increased and refolding yields are lower. Tightly bound aggregates were removed from the column by 2M guanidinium hydrochloride. In order to increase the system yield, this aggregate fraction was recycled after lowering the conductivity by ultradiafiltration and adjustment of the protein concentration by dilution. For on-column refolding, recycling of aggregates at a recycling rate of 0.17 increased the system yield from 25% to 30%. An algorithm was developed to show interdependencies of the single influencing parameters. The operability of the system was demonstrated but limitations due to instability of the P-CAC, especially inhomogeneous flow and peak wobbling, have to be considered.

  3. An Algorithm for Source Checking Continuous Air Monitors Using Radon Progeny

    SciTech Connect

    Hogue, M.G.

    2000-03-06

    Department of Energy requirements contained within 10CFR835 require that continuous air monitors be periodically checked for operability. The DOE air monitoring implementation guide for 10CFR835 allows the use of radon progeny to perform the recommended weekly source check. The Defense Waste Processing Facility located at the Savannah River Site has demonstrated that, through the use of the Hypotheses Concerning Two Means, diurnal changes in the radon progeny detected by the monitors meets the requirements for weekly source checks. The use of the diurnal changes in radon progeny has replaced the man-hours expended performing direct weekly source checking with an automated system requiring minimal man-hour expenditure.

  4. OPERATIONAL LIMITATIONS FOR DEMOLITION OF A HIGHLY ALPHA CONTAMINATED BUILDING MODLES VERSUS MEASURED AIR & SURFACE ACTIVITY CONCENTRATIONS

    SciTech Connect

    LLOYD, E.R.

    2006-11-02

    The demolition of a facility historically used for processing and handling transuranic materials is considered. Residual alpha emitting radionuclide contamination poses an exposure hazard if released to the local environment during the demolition. The process of planning for the demolition of this highly alpha contaminated building, 232-Z, included a predemolition modeling analysis of potential exposures. Estimated emission rates were used as input to an air dispersion model to estimate frequencies of occurrence of peak air and surface exposures. Postdemolition modeling was also conducted, based on the actual demolition schedule and conditions. The modeling results indicated that downwind deposition is the main operational limitation for demolition of a highly alpha-contaminated building. During the demolition of 232-Z, airborne radiation and surface contamination were monitored. The resultant non-detect monitoring results indicate a significant level of conservatism in the modeled results. This comparison supports the use of more realistic assumption in the estimating emission rates. The resultant reduction in modeled levels of potential exposures has significant implications in terms of the projected costs of demolition of such structures.

  5. Certolizumab pegol: new drug. As a last resort in Crohn's disease: continue to use other TNF alpha inhibitors.

    PubMed

    2009-06-01

    basis, while adalimumab is injected twice a month; (9) In practice, as with other TNF alpha inhibitors used in Crohn's disease, certolizumab pegol is only modestly effective and carries a disturbing risk of adverse effects. In the absence of a better alternative, patients with Crohn's disease who might benefit from TNF alpha inhibitor therapy should continue to receive either infliximab or adalimumab, two drugs with which we have more experience.

  6. A method for near real time continuous air monitoring of phosgene, hydrogen cyanide, and cyanogen chloride

    SciTech Connect

    Lattin, F.G.; Paul, D.G.

    1996-12-31

    A sorbent-based gas chromatographic method provides continuous quantitative measurement of phosgene, hydrogen cyanide, and cyanogen chloride in ambient air. These compounds are subject to workplace exposure limits as well as regulation under terms of the Chemical Arms Treaty and Title III of the 1990 Clean Air Act amendments. The method was developed for on-site use in a mobile laboratory during remediation operations. Incorporated into the method are automated multi-level calibrations at time weighted average (TW) concentrations, or lower. Gaseous standards are prepared in fused silica lined air sampling canisters, then transferred to the analytical system through dynamic spiking. Precision and accuracy studies performed to validate the method are described. Also described are system deactivation and passivation techniques critical to optimum method performance.

  7. Use of Source Term and Air Dispersion Modeling in Planning Demolition of Highly Alpha-Contaminated Buildings

    SciTech Connect

    Droppo, James G.; Napier, Bruce A.; Rishel, Jeremy P.; Bloom, Richard W.

    2011-06-22

    The current cleanup of structures related to cold-war production of nuclear materials includes the need to demolish a number of highly alpha-contaminated structures. The process of planning for the demolition of such structures includes unique challenges related to ensuring the protection of both workers and the public. Pre-demolition modeling analyses were conducted to evaluate potential exposures resulting from the proposed demolition of a number of these structures. Estimated emission rates of transuranic materials during demolition are used as input to an air-dispersion model. The climatological frequencies of occurrence of peak air and surface exposures at locations of interest are estimated based on years of hourly meteorological records. The modeling results indicate that downwind deposition is the main operational limitation for demolition of a highly alpha-contaminated building. The pre-demolition modeling directed the need for better contamination characterization and/or different demolition methods—and in the end, provided a basis for proceeding with the planned demolition activities. Post-demolition modeling was also conducted for several contaminated structures, based on the actual demolition schedule and conditions. Comparisons of modeled and monitoring results are shown. Recent monitoring data from the demolition of a UO3 plant shows increments in concentrations that were previously identified in the pre-demolition modeling predictions; these comparisons confirm the validity and value of the pre-demolition source-term and air dispersion computations for planning demolition activities for other buildings with high levels of radioactive contamination.

  8. Continuous multichannel monitoring of cave air carbon dioxide using a pumped non-dispersive infrared analyser

    NASA Astrophysics Data System (ADS)

    Mattey, D.

    2012-04-01

    The concentration of CO2 in cave air is one of the main controls on the rate of degassing of dripwater and on the kinetics of calcite precipitation forming speleothem deposits. Measurements of cave air CO2reveal great complexity in the spatial distribution among interconnected cave chambers and temporal changes on synoptic to seasonal time scales. The rock of Gibraltar hosts a large number of caves distributed over a 300 meter range in altitude and monthly sampling and analysis of air and water combined with continuous logging of temperature, humidity and drip discharge rates since 2004 reveals the importance of density-driven seasonal ventilation which drives large-scale advection of CO2-rich air though the cave systems. Since 2008 we have deployed automatic CO2 monitoring systems that regularly sample cave air from up to 8 locations distributed laterally and vertically in St Michaels Cave located near the top of the rock at 275m asl and Ragged Staff Cave located in the heart of the rock near sea level. The logging system is controlled by a Campbell Scientific CR1000 programmable datalogger which controls an 8 port manifold connected to sampling lines leading to different parts of the cave over a distance of up to 250 meters. The manifold is pumped at a rate of 5l per minute drawing air through 6mm or 8mm id polythene tubing via a 1m Nafion loop to reduce humidity to local ambient conditions. The outlet of the primary pump leads to an open split which is sampled by a second low flow pump which delivers air at 100ml/minute to a Licor 820 CO2 analyser. The software selects the port to be sampled, flushes the line for 2 minutes and CO2 analysed as a set of 5 measurements averaged over 10 second intervals. The system then switches to the next port and when complete shuts down to conserve power after using 20 watts over a 30 minute period of analysis. In the absence of local mains power (eg from the show cave lighting system) two 12v car batteries will power the system

  9. cap alpha. -dicarbonyl yields from the NO/sub x/ - air photooxidations of a series of aromatic hydrocarbons in air

    SciTech Connect

    Tuazon, E.C.; Mac Leod, H.; Atkinson, R.; Carter, W.P.L.

    1986-04-01

    The yields of the ring cleavage products glyoxal, methylglyoxal, and biacetyl from the reactions of OH radicals with benzene, toluene, o-, m-, and p-xylene, and 1,2,3-, 1,2,4-, and 1,3,5-trimethylbenzene in the presence of parts per million concentrations of NO have been determined in 1 atm of air at 298 +/- 2 K using in situ long-path-length Fourier transform infrared absorption spectroscopy and differential optical absorption spectroscopy with supplementary gas chromatographic analyses. These data are important inputs to chemical models of the NO/sub x/-air photoxidations of these aromatic hydrocarbons. 25 references, 3 figures, 1 table.

  10. Measurement of air exchange rates in different indoor environments using continuous CO2 sensors.

    PubMed

    You, Yan; Niu, Can; Zhou, Jian; Liu, Yating; Bai, Zhipeng; Zhang, Jiefeng; He, Fei; Zhang, Nan

    2012-01-01

    A new air exchange rate (AER) monitoring method using continuous CO2 sensors was developed and validated through both laboratory experiments and field studies. Controlled laboratory simulation tests were conducted in a 1-m3 environmental chamber at different AERs (0.1-10.0 hr(-1)). AERs were determined using the decay method based on box model assumptions. Field tests were conducted in classrooms, dormitories, meeting rooms and apartments during 2-5 weekdays using CO2 sensors coupled with data loggers. Indoor temperature, relative humidity (RH), and CO2 concentrations were continuously monitored while outdoor parameters combined with on-site climate conditions were recorded. Statistical results indicated that good laboratory performance was achieved: duplicate precision was within 10%, and the measured AERs were 90%-120% of the real AERs. Average AERs were 1.22, 1.37, 1.10, 1.91 and 0.73 hr(-1) in dormitories, air-conditioned classrooms, classrooms with an air circulation cooling system, reading rooms, and meeting rooms, respectively. In an elderly particulate matter exposure study, all the homes had AER values ranging from 0.29 to 3.46 hr(-1) in fall, and 0.12 to 1.39 hr(-1) in winter with a median AER of 1.15.

  11. The two-dimensional calculation of the temperature field of a continuous optical discharge in air

    NASA Astrophysics Data System (ADS)

    Raizer, Iu. P.; Silantev, A. Iu.

    1986-03-01

    A two-dimensional temperature field present in a continuous optical discharge in air sustained by CO2 laser radiation is computed numerically. Consideration is given to both laser beam refraction in the discharge and radiative heat transfer. It is found that the refraction induces strong caustic broadening as well as displacement of the constriction region towards the beam, so that the discharge is located in the region of highest radiation intensity. Hence, the phenomenon whereby high-output optical discharge never burns at the geometrical locus (even when there is sufficient radiation power) is explained. Power output and lens focussing are used to find the threshold and upper limits of discharge existence.

  12. Two-dimensional calculations of a continuous optical discharge in atmospheric air flow (optical plasma generator)

    NASA Astrophysics Data System (ADS)

    Raizer, Iu. P.; Silant'ev, A. Iu.; Surzhikov, S. T.

    1987-06-01

    Two-dimensional gasdynamic processes in a continuous optical discharge in subsonic flow of atmospheric air are simulated numerically with allowance for distortions of the light channel due to laser beam refraction in the generated plasma, radiative energy losses, and radiant heat transfer. It is found that instabilities and vortex structures are formed in the hot jet behind the energy release region; flow in this region is nonstationary but periodic. These effects are not observed in the main part of the discharge, which is quite stable. Depending on flow velocity, diffraction in the plasma may lead to both defocusing and focusing of the beam.

  13. Characterization of a New Continuous Air Monitoring System For the University of Massachusetts Lowell Research Reactor

    NASA Astrophysics Data System (ADS)

    Alqahtani, Mohammad Saad

    A continuous air monitor (CAM) is a critical piece of equipment to support radiation safety in nuclear facilities where the generation of airborne radioactivity is a possibility for either normal operations or accident scenarios. The University of Massachusetts Lowell Research Reactor is planning to install a new CAM system manufactured by Canberra Industries for monitoring airborne radioactive particulates. In this study, the new CAM was evaluated to determine 1) baseline response, 2) response to high exposure rates, 3) appropriate background compensation, 4) detection limits, and 5) alarm settings. The results of this study will help to properly integrate the new CAM into the reactor radiation monitoring system.

  14. Evaluation of the Eberline AMS-3A and AMS-4 Beta continuous air monitors

    SciTech Connect

    Johnson, M.L.; Sisk, D.R.

    1996-03-01

    Eberline AMS-3A-1 and AMS-4 beta continuous air monitors were tested against the criteria set forth in the ANSI Standards N42.18, Specification and Performance of On-site Instrumentation for Continuously Monitoring Radioactivity in Effluents, and ANSI N42.17B, Performance Specification for Health Physics Instrumentation - Occupational Airborne Radioactivity Monitoring Instrumentation. ANSI N42.18 does not, in general, specify testing procedures for demonstrating compliance with the criteria set forth in the standard; therefore, wherever possible, the testing procedures given in ANSI N42.17B were adopted. In all cases, the more restrictive acceptance criteria and/or the more demanding test conditions of the two standards were used.

  15. Practical strategies for stable operation of HFF-QCM in continuous air flow.

    PubMed

    Wessels, Alexander; Klöckner, Bernhard; Siering, Carsten; Waldvogel, Siegfried R

    2013-09-09

    Currently there are a few fields of application using quartz crystal microbalances (QCM). Because of environmental conditions and insufficient resolution of the microbalance, chemical sensing of volatile organic compounds in an open system was as yet not possible. In this study we present strategies on how to use 195 MHz fundamental quartz resonators for a mobile sensor platform to detect airborne analytes. Commonly the use of devices with a resonant frequency of about 10 MHz is standard. By increasing the frequency to 195 MHz the frequency shift increases by a factor of almost 400. Unfortunately, such kinds of quartz crystals tend to exhibit some challenges to obtain a reasonable signal-to-noise ratio. It was possible to reduce the noise in frequency in a continuous air flow of 7.5 m/s to 0.4 Hz [i.e., σ(τ) = 2 × 10-9] by elucidating the major source of noise. The air flow in the vicinity of the quartz was analyzed to reduce turbulences. Furthermore, we found a dependency between the acceleration sensitivity and mechanical stress induced by an internal thermal gradient. By reducing this gradient, we achieved reduction of the sensitivity to acceleration by more than one decade. Hence, the resulting sensor is more robust to environmental conditions such as temperature, acceleration and air flow.

  16. Practical Strategies for Stable Operation of HFF-QCM in Continuous Air Flow

    PubMed Central

    Wessels, Alexander; Klöckner, Bernhard; Siering, Carsten; Waldvogel, Siegfried R.

    2013-01-01

    Currently there are a few fields of application using quartz crystal microbalances (QCM). Because of environmental conditions and insufficient resolution of the microbalance, chemical sensing of volatile organic compounds in an open system was as yet not possible. In this study we present strategies on how to use 195 MHz fundamental quartz resonators for a mobile sensor platform to detect airborne analytes. Commonly the use of devices with a resonant frequency of about 10 MHz is standard. By increasing the frequency to 195 MHz the frequency shift increases by a factor of almost 400. Unfortunately, such kinds of quartz crystals tend to exhibit some challenges to obtain a reasonable signal-to-noise ratio. It was possible to reduce the noise in frequency in a continuous air flow of 7.5 m/s to 0.4 Hz [i.e., σ(τ) = 2 × 10−9] by elucidating the major source of noise. The air flow in the vicinity of the quartz was analyzed to reduce turbulences. Furthermore, we found a dependency between the acceleration sensitivity and mechanical stress induced by an internal thermal gradient. By reducing this gradient, we achieved reduction of the sensitivity to acceleration by more than one decade. Hence, the resulting sensor is more robust to environmental conditions such as temperature, acceleration and air flow. PMID:24021970

  17. Incorrect interpretation of moving-filter continuous particulate air monitor responses.

    PubMed

    Evans, William C

    2013-04-01

    The graphs supplied by the vendors of moving-filter continuous particulate air monitors (CPAMs) in their sales literature show linear curves on a log-log scale, with net count rate on one axis and concentration on the other. The implication is that the monitor user is to read the concentration from the graph, given an observed net count rate, at any time. For the nominal filter speeds commonly used for these monitors, using the graph in this way is incorrect. The graphs do not state the limitations of the calculation: (1) the nuclide measured must be long-lived; (2) the concentration of that nuclide in the sampled air must remain constant; and (3) the reading of the net count rate must be obtained after a specific time, called the "transit time." This time is typically on the order of several hours. Reading the net count rate at any time earlier than this will result in an incorrect concentration estimate. Given that a major purpose of a CPAM is to alert plant personnel to a change in airborne radioactivity concentrations, by definition when this happens the concentration is not constant. Thus, using the supplied curves will result in an incorrect estimate of that concentration. The solution is to use instead a fixed-filter CPAM and a previously-published quantitative method. With this approach, there is no need to attempt to estimate a concentration, much less to assume that it is constant over long periods of time or that it can only change in a stair-step manner. With this alternative to a moving-filter CPAM, a signal proportional to the time-integrated worker intake can be generated continuously for any time-varying air concentration, including the sums-of-exponentials shapes expected during transient events in compartmental systems.

  18. Operation Greenhouse. Scientific Director's report of atomic-weapon tests at Eniwetok, 1951. Annex 1. 9. Air-drop instrumentation. Part 2. Teller-alpha

    SciTech Connect

    Grier, H.E.

    1985-09-01

    It was the purpose of the Teller-Alpha experiment to measure the coefficient alpha by means of detectors placed a long distance from the bomb. The detectors are photoelectric devices that respond to visible light produced in the air surrounding the bomb by the absorbed gamma rays. A measurement of this sort was proposed by Edward Teller prior to the Sandstone Operation. The main components of the Teller-Alpha equipment were the photohead, the 200-Mc timing oscillator, and the high-speed-sensitivity recoding oscilloscope. A complete discussion of the experiment is provided.

  19. Definition and means of maintaining the room continuous air monitors portion of the plutonium finishing plant (PFP) safety envelope

    SciTech Connect

    WHITE, W.F.

    1999-05-20

    Room Continuous Air Monitors (CAMs) are used in areas where there is potential for dispersible radioactive material. These CAMs provide audible and visual alarms to warn personnel of an increase in airborne radioactivity.

  20. Comparison of orthorhombic and alpha-two titanium aluminides as matrices for continuous SiC-reinforced composites

    NASA Astrophysics Data System (ADS)

    Smith, P. R.; Graves, J. A.; Rhodes, Cg.

    1994-06-01

    The attributes of an orthorhombic Ti aluminide alloy, Ti-21Al-22Nb (at. pct), and an alpha-two Ti aluminide alloy, Ti-24Al-11Nb (at. pct), for use as a matrix with continuous SiC (SCS-6) fiber reinforcement have been compared. Foil-fiber-foil processing was used to produce both unreinforced (“neat”) and unidirectional “SCS-6” reinforced panels. Microstructure of the Ti-24A1-11Nb matrix consisted of ordered Ti3Al ( α 2) + disordered beta (β), while the Ti-21 Al-22Nb matrix contained three phases: α2, ordered beta ( β 0), and ordered orthorhombic (O). Fiber/ matrix interface reaction zone growth kinetics at 982 °C were examined for each composite system. Although both systems exhibited similar interface reaction products (i.e., mixed Ti carbides, silicides, and Ti-Al carbides), growth kinetics in the α 2 + β matrix composite were much more rapid than in the O + β 0 + α 2 matrix composite. Additionally, interfacial reaction in the α 2 + β} composite resulted in a relatively large brittle matrix zone, depleted of beta phase, which was not present in the O + β 0+ α 2 matrix composite. Mechanical property measurements included room and elevated temperature tensile, thermal stability, thermal fatigue, thermo-mechanical fatigue (TMF), and creep. The three-phase orthorhombic-based alloy outperformed the α2+ β alloy in all of these mechanical behavioral areas, on both an absolute and a specific (i.e., density corrected) basis.

  1. Alpha-dicarbonyl yields from the NOx-air photooxidations of a series of aromatic hydrocarbons in air

    SciTech Connect

    Tuazon, E.C.; Mac Leod, H.; Atkinson, R.; Carter, W.P.L.

    1986-01-01

    The yields of the ring-cleavage products glyoxal, methylglyoxal and biacetyl from the reactions of OH radicals with benzene, toluene, o-, m- and p-xylene and 1,2,3-, 1,2,4- and 1,3,5-trimethylbenzene in the presence of part-per-million concentrations of NO have been determined in one atmosphere of air using in-situ long pathlength Fourier-transform infrared absorption spectroscopy and differential optical absorption spectroscopy with supplementary gas-chromatographic analyses. The yields of glyoxal and methylglyoxal were respectively: from toluene, 0.105 plus or minus 0.019 and 0.146 plus or minus 0.006; from o-xylene, 0.087 plus or minus 0.012 and 0.246 plus or minus 0.020; from m-xylene, 0.086 plus or minus 0.011 and 0.319 plus or minus 0.009; from p-xylene, 0.225 plus or minus 0.039 and 0.105 plus or minus 0.034; from 1,2,3-trimethylbenzene, 0.058 plus or minus 0.008 and 0.152 plus or minus 0.025; and from 1,2,4-trimethylbenzene, 0.048 plus or minus 0.005 and 0.357 plus or minus 0.017.

  2. Outdoor air pollution in close proximity to a continuous point source

    NASA Astrophysics Data System (ADS)

    Klepeis, Neil E.; Gabel, Etienne B.; Ott, Wayne R.; Switzer, Paul

    Data are lacking on human exposure to air pollutants occurring in ground-level outdoor environments within a few meters of point sources. To better understand outdoor exposure to tobacco smoke from cigarettes or cigars, and exposure to other types of outdoor point sources, we performed more than 100 controlled outdoor monitoring experiments on a backyard residential patio in which we released pure carbon monoxide (CO) as a tracer gas for continuous time periods lasting 0.5-2 h. The CO was emitted from a single outlet at a fixed per-experiment rate of 120-400 cc min -1 (˜140-450 mg min -1). We measured CO concentrations every 15 s at up to 36 points around the source along orthogonal axes. The CO sensors were positioned at standing or sitting breathing heights of 2-5 ft (up to 1.5 ft above and below the source) and at horizontal distances of 0.25-2 m. We simultaneously measured real-time air speed, wind direction, relative humidity, and temperature at single points on the patio. The ground-level air speeds on the patio were similar to those we measured during a survey of 26 outdoor patio locations in 5 nearby towns. The CO data exhibited a well-defined proximity effect similar to the indoor proximity effect reported in the literature. Average concentrations were approximately inversely proportional to distance. Average CO levels were approximately proportional to source strength, supporting generalization of our results to different source strengths. For example, we predict a cigarette smoker would cause average fine particle levels of approximately 70-110 μg m -3 at horizontal distances of 0.25-0.5 m. We also found that average CO concentrations rose significantly as average air speed decreased. We fit a multiplicative regression model to the empirical data that predicts outdoor concentrations as a function of source emission rate, source-receptor distance, air speed and wind direction. The model described the data reasonably well, accounting for ˜50% of the log

  3. Two-dimensional calculations of a continuous optical discharge in atmospheric-air flow (optical plasmatron)

    SciTech Connect

    Raizer, Yu.P.; Silant'ev, A.Yu.; Surzhikov, S.T.

    1987-11-01

    A two-dimensional gas-dynamic process in a continuous optical discharge, burning in subsonic atmospheric-air flow, is modeled numerically. The distortion of the light channel owing to refraction of the laser beam in the plasma created by it, the radiative energy losses, and radiant heat transfer were taken into account. It was found that in a hot jet instabilities and eddy structures appear behind the region of energy liberation. These effects do not affect the main part of the discharge, where the state is completely stable. The calculations showed that for an optical plasmatron in the free atmosphere the incoming flow primarily flows around the highly heated region, and penetrates into it only slightly. Depending on the velocity of the flow the refraction in the plasma can lead to both defocusing and additional focusing of the beam. The results agree qualitatively with available experimental data.

  4. Continuous high order sliding mode controller design for a flexible air-breathing hypersonic vehicle.

    PubMed

    Wang, Jie; Zong, Qun; Su, Rui; Tian, Bailing

    2014-05-01

    This paper investigates the problem of tracking control with uncertainties for a flexible air-breathing hypersonic vehicle (FAHV). In order to overcome the analytical intractability of this model, an Input-Output linearization model is constructed for the purpose of feedback control design. Then, the continuous finite time convergence high order sliding mode controller is designed for the Input-Output linearization model without uncertainties. In addition, a nonlinear disturbance observer is applied to estimate the uncertainties in order to compensate the controller and disturbance suppression, where disturbance observer and controller synthesis design is obtained. Finally, the synthesis of controller and disturbance observer is used to achieve the tracking for the velocity and altitude of the FAHV and simulations are presented to illustrate the effectiveness of the control strategies.

  5. Photocatalysis for continuous air purification in wastewater treatment plants: from lab to reality.

    PubMed

    Portela, R; Tessinari, R F; Suárez, S; Rasmussen, S B; Hernández-Alonso, M D; Canela, M C; Avila, P; Sánchez, B

    2012-05-01

    The photocatalytic efficiency of TiO(2)-SiMgO(x) plates to oxidize H(2)S was first evaluated in a flat laboratory reactor with 50 mL min(-1) synthetic air containing 100 ppm H(2)S in the presence of humidity. The use of the photocatalyst-adsorbent hybrid material enhanced the photocatalytic activity in terms of pollutant conversion, selectivity, and catalyst lifetime compared to previous H(2)S tests with pure TiO(2) because total H(2)S elimination was maintained for more than 30 operating hours with SO(2) appearing in the outlet as reaction product only after 18 h. Subsequently, the hybrid material was successfully tested in a photoreactor prototype to treat real polluted air in a wastewater treatment plant. For this purpose, a new tubular photocatalytic reactor that may use solar radiation in combination with artificial radiation was designed; the lamp was turned on when solar UV-A irradiance was below 20 W m(-2), which was observed to be the minimum value to ensure 100% conversion. The efficient distribution of the opaque photocatalyst inside the tubular reactor was achieved by using especially designed star-shaped structures. These structures were employed for the arrangement of groups of eight TiO(2)-SiMgO(x) plates in easy-to-handle channelled units obtaining an adequate flow regime without shading. The prototype continuously removed during one month and under real conditions the H(2)S contained in a 1 L min(-1) air current with a variable inlet concentration in the range of tens of ppmv without release of SO(2). PMID:22443317

  6. Photocatalysis for continuous air purification in wastewater treatment plants: from lab to reality.

    PubMed

    Portela, R; Tessinari, R F; Suárez, S; Rasmussen, S B; Hernández-Alonso, M D; Canela, M C; Avila, P; Sánchez, B

    2012-05-01

    The photocatalytic efficiency of TiO(2)-SiMgO(x) plates to oxidize H(2)S was first evaluated in a flat laboratory reactor with 50 mL min(-1) synthetic air containing 100 ppm H(2)S in the presence of humidity. The use of the photocatalyst-adsorbent hybrid material enhanced the photocatalytic activity in terms of pollutant conversion, selectivity, and catalyst lifetime compared to previous H(2)S tests with pure TiO(2) because total H(2)S elimination was maintained for more than 30 operating hours with SO(2) appearing in the outlet as reaction product only after 18 h. Subsequently, the hybrid material was successfully tested in a photoreactor prototype to treat real polluted air in a wastewater treatment plant. For this purpose, a new tubular photocatalytic reactor that may use solar radiation in combination with artificial radiation was designed; the lamp was turned on when solar UV-A irradiance was below 20 W m(-2), which was observed to be the minimum value to ensure 100% conversion. The efficient distribution of the opaque photocatalyst inside the tubular reactor was achieved by using especially designed star-shaped structures. These structures were employed for the arrangement of groups of eight TiO(2)-SiMgO(x) plates in easy-to-handle channelled units obtaining an adequate flow regime without shading. The prototype continuously removed during one month and under real conditions the H(2)S contained in a 1 L min(-1) air current with a variable inlet concentration in the range of tens of ppmv without release of SO(2).

  7. Thermal imaging and air-coupled ultrasound characterization of a continuous-fiber ceramic composite panels.

    SciTech Connect

    Sun, J. G.; Easler, T. E.; Szweda, A.; Pillai, T. A. K.; Deemer, C.; Ellingson, W. A.

    1998-04-01

    SYLRAMIC{trademark} continuous fiber ceramic-matrix composites (Nicalon{trademark} fiber/SiNC matrix) were fabricated by Dow Corning Corporation with the polymer-impregnation and pyrolysis (PIP) process. The composite microstructure and its uniformity, and the completeness of infiltration during processing were studied as a function of number of PIP cycles. Two nondestructive evaluation (NDE) methods, i.e., infrared thermal imaging and air-coupled ultrasound (UT), were used to investigate flat composite panels of two thicknesses and various sizes. The thermal imaging method provided two-dimensional (2D) images of through-thickness thermal diffusivity distributions, and the air-coupled UT method provided 2D images of through-thickness ultrasonic transmission of the panel components. Results from both types of NDEs were compared at various PIP cycles during fabrication of the composites. A delaminated region was clearly detected and its progressive repair was monitored during processing. The NDE data were also correlated to results obtained from destructive characterization.

  8. Application of continuous remote sensing of mixing layer height for assessment of airport air quality

    NASA Astrophysics Data System (ADS)

    Schäfer, Klaus; Helmis, Costas; Emeis, Stefan; Sgouros, George; Kurtenbach, Ralf; Wiesen, Peter; Münkel, Christoph; Jahn, Carsten; Hoffmann, Maria; Anamaterou, Evi; O'Connor, Michael

    2010-10-01

    The assessment of airport air quality requires not only the knowledge of the emissions and the temporal and spatial distribution of meteorological parameters like wind direction and wind speed but also of the mixing layer height, because this variable controls the vertical space for rapid mixing of near-surface pollutants. It was demonstrated that the lowest stable layer or temperature inversion limits the vertical exchange of primary pollutants emitted at or near the surface and thus controls the near-surface pollutant concentrations. Remote sensing is a suitable tool to determine mixing layer height continuously as was demonstrated in urban and sub-urban areas (Hannover, Munich, Budapest, Augsburg) as well as at airports (Zurich, Paris CDG, Mexico City International Airport, Athens International Airport). The Vaisala ceilometer LD40 was used which is an eye-safe commercial lidar and designed originally to detect cloud base heights and vertical visibility for aviation safety purposes. These measurements of the vertical aerosol distribution are routinely retrieved for mixing layer height estimation by using software which was improved continuously and compared with radiosonde data. Further, mixing layer height was determined by remote sensing with a combination of a Doppler- SODAR (Sound Detection and Ranging), a RASS (Radio Acustic Sounding System) and in-situ measurements. Vertical wind, temperature and turbulence parameter profiles up to 1500 m maximum were measured by this method too. Some results of interpretation of measured data at Athens International Airport will be discussed as the influence of mixing layer height upon airport air quality and estimation of the airport emission source strengths.

  9. Detectors for alpha particles and X-rays operating in ambient air in pulse counting mode or/and with gas amplification

    NASA Astrophysics Data System (ADS)

    Charpak, G.; Benaben, P.; Breuil, P.; Peskov, V.

    2008-02-01

    Ionization chambers working in ambient air in current detection mode are attractive due to their simplicity and low cost and are widely used in several applications such as smoke detection, dosimetry, therapeutic beam monitoring and so on. The aim of this work was to investigate if gaseous detectors can operate in ambient air in pulse counting mode as well as with gas amplification which potentially offers the highest possible sensitivity in applications like alpha particle detection or high energy X-ray photon or electron detection. To investigate the feasibility of this method two types of open- end gaseous detectors were build and successfully tested. The first one was a single wire or multiwire cylindrical geometry detector operating in pulse mode at a gas gain of one (pulse ionization chamber). This detector was readout by a custom made wide -band charge sensitive amplifier able to deal with slow induced signals generated by slow motion of negative and positive ions. The multiwire detector was able to detect alpha particles with an efficiency close to 22%. The second type of an alpha detector was an innovative GEM-like detector with resistive electrodes operating in air in avalanche mode at high gas gains (up to 104). This detector can also operate in a cascaded mode or being combined with other detectors, for example with MICROMEGAS. This detector was readout by a conventional charge -sensitive amplifier and was able to detect alpha particles with 100% efficiency. This detector could also detect X-ray photons or fast electrons. A detailed comparison between these two detectors is given as well as a comparison with commercially available alpha detectors. The main advantages of gaseous detectors operating in air in a pulse detection mode are their simplicity, low cost and high sensitivity. One of the possible applications of these new detectors is alpha particle background monitors which, due to their low cost can find wide application not only in houses, but

  10. Summary of second generation alpha CAM testing performed at Hanford

    SciTech Connect

    Johnson, M.L.; Sisk, D.R.; Goles, R.W.; Swinth, K.L.; Tinker, M.R.; Hickey, E.E.

    1994-05-01

    Pacific Northwest Laboratory and Westinghouse Hanford Company tested six models of commercially available alpha continuous air monitors (CAMs): the Canberra Alpha Sentry, Eberline Alpha 6A-1, Merlin Gerin A-CAM, NE America CAM1A, SAIC/RADeCO Model 452, and Victoreen Model 758. The CAMs were tested for calibration and workmanship, performance in various environments, and human factors for field use.

  11. Some Analysis of Integrated-count Processing for Fixed-filter Continuous Particulate Air Monitors.

    PubMed

    Evans, William C

    2016-09-01

    A calculation for estimating concentrations of long-lived airborne particulate radioactivity using fixed-filter continuous air monitors is given in an ISO standard. The method uses counts integrated over relatively long time intervals, rather than the 'instantaneous' count rates that in digital systems are evaluated using much shorter time intervals and some form of variance-reduction filtering. This article presents three ways of deriving and interpreting this calculation, based on previously published mathematical models that were derived from first principles. The method is also extended here to apply for short-lived activity. Some statistical properties of the estimator are discussed, including its time-dependent variance and the presence of strong autocorrelation in the concentration estimates. An interactive simulation was used to examine the performance of the concentration estimation, using physically plausible concentration time-dependence profiles; example plots are provided. The conclusion of these studies is that the method, as modified herein, can perform remarkably well in providing periodic average-concentration estimates for both long- and short-lived activity, and it should be considered an appropriate method in those situations where the tracking of a time-dependent concentration is deemed necessary. PMID:27472754

  12. Continuous electricity generation by a graphite granule baffled air-cathode microbial fuel cell.

    PubMed

    Feng, Yujie; Lee, He; Wang, Xin; Liu, Yaolan; He, Weihua

    2010-01-01

    A baffled air-cathode microbial fuel cell (BAFMFC) was designed and operated under continuous flow. With glucose fed as substrate, an average voltage of 652 mV was obtained under the external resistance of 1000 Omega (30 degrees C). The maximum power density was 15.2 W/m(3) with the chemical oxygen demand (COD) removal rate of 88.0%. The overall resistance was 13.7 Omega while ohmic internal resistance was 10.8 Omega. Average COD removal rate was 69.7-88.0%, when COD loading varied from 4.11 kg COD/(m(3)NACd) to 16.0 kg COD/(m(3)NACd). The liquid from corn stover steam explosion process (COD=7160+/-50mg/L) was treated by BAFMFC, and the maximum power density was 10.7 W/m(3) with the average COD removal rate was 89.1%. The present study indicated BAFMFC can be comparable to the traditional anaerobic baffled reactor in COD removal rate for high-concentration wastewater and have an advantage in energy harvest from wastewater.

  13. Uncertainties in Air Exchange using Continuous-Injection, Long-Term Sampling Tracer-Gas Methods

    SciTech Connect

    Sherman, Max H.; Walker, Iain S.; Lunden, Melissa M.

    2013-12-01

    The PerFluorocarbon Tracer (PFT) method is a low-cost approach commonly used for measuring air exchange in buildings using tracer gases. It is a specific application of the more general Continuous-Injection, Long-Term Sampling (CILTS) method. The technique is widely used but there has been little work on understanding the uncertainties (both precision and bias) associated with its use, particularly given that it is typically deployed by untrained or lightly trained people to minimize experimental costs. In this article we will conduct a first-principles error analysis to estimate the uncertainties and then compare that analysis to CILTS measurements that were over-sampled, through the use of multiple tracers and emitter and sampler distribution patterns, in three houses. We find that the CILTS method can have an overall uncertainty of 10-15percent in ideal circumstances, but that even in highly controlled field experiments done by trained experimenters expected uncertainties are about 20percent. In addition, there are many field conditions (such as open windows) where CILTS is not likely to provide any quantitative data. Even avoiding the worst situations of assumption violations CILTS should be considered as having a something like a ?factor of two? uncertainty for the broad field trials that it is typically used in. We provide guidance on how to deploy CILTS and design the experiment to minimize uncertainties.

  14. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  15. Continuous Distributions of Ventilation-Perfusion Ratios in Normal Subjects Breathing Air and 100% O2

    PubMed Central

    Wagner, Peter D.; Laravuso, Raymond B.; Uhi, Richard R.; West, John B.

    1974-01-01

    A new method has been developed for measuring virtually continuous distributions of ventilation-perfusion ratios (V̇A/Q̇) based on the steadystate elimination of six gases of different solubilities. The method is applied here to 12 normal subjects, aged 21—60. In nine, the distributions were compared breathing air and 100% oxygen, while in the remaining three, effects of changes in posture were examined. In four young semirecumbent subjects (ages 21—24) the distributions of blood flow and ventilation with respect to V̇A/Q̇ were virtually log-normal with little dispersion (mean log standard deviations 0.43 and 0.35, respectively). The 95.5% range of both blood flow and ventilation was from V̇A/Q̇ ratios of 0.3—2.1, and there was no intrapulmonary shunt (V̇A/Q̇ of 0). On breathing oxygen, a shunt developed in three of these subjects, the mean value being 0.5% of the cardiac output. The five older subjects (ages 39—60) had broader distributions (mean log standard deviations, 0.76 and 0.44) containing areas with V̇A/Q ratios in the range 0.01—0.1 in three subjects. As for the young subjects, there was no shunt breathing air, but all five developed a shunt breathing oxygen (mean value 3.2%), and in one the value was 10.7%. Postural changes were generally those expected from the known effects of gravity, with more ventilation to high VA/Q areas when the subjects were erect than supine. Measurements of the shunt while breathing oxygen, the Bohr CO2 dead space, and the alveolar-arterial oxygen difference were all consistent with the observed distributions. Since the method involves only a short infusion of dissolved inert gases, sampling of arterial blood and expired gas, and measurement of cardiac output and minute ventilation, we conclude that it is well suited to the investigation of pulmonary gas exchange in man. PMID:4601004

  16. Continuous extraction of alpha- and beta-amylases from Zea mays malt in a PEG4000/CaCl2 ATPS.

    PubMed

    Biazus, J P M; Santana, J C C; Souza, R R; Jordão, E; Tambourgi, E B

    2007-10-15

    In the present work, alpha- and beta-amylase enzymes from Zea mays malt were recovered by continuous extraction in a PEG/CaCl2 aqueous two-phase system (ATPS). The influences of the flux rate (RQ), free area of vane (A(free)) and vane rotation (RV) on enzyme recovery were studied by optimization using response surface methodology (RSM). The protein content and enzyme activity were measured from time to time in the extract and refined fluxes. RSM curves showed a squared dependence of recovery index with the RQ, A(free) and RV. The best system for recovering the maize malt enzymes was with low vane rotation and flux rate and high free area of vane. Alpha- and beta-amylases were purified 130-fold in the salt-rich phase.

  17. Computation of conversion coefficients relating air Kerma to Hp(0.07,alpha), Hp(10,alpha), and H*(10) for x-ray narrow spectrum from 40 to 140 kV.

    PubMed

    Kharrati, Hedi; Zarrad, Boubaker

    2004-02-01

    A computation method was implemented to predict the conversion coefficients and the angular dependence factors relating air Kerma to Hp(0.07,alpha), Hp(10,alpha), and H*(10) in an ICRU slab phantom for tungsten anode x-ray spectra for tube potentials from 40 to 140 kV. The simulation of the unfiltered x-ray spectra is based on the Boone and Seibert model. The calculation of conversion coefficients were performed for an x-ray narrow spectrum at any filtration material and tube potentials in the diagnostic radiology range. This computation method has been checked for five narrow x-ray spectra using a comparison of the results with published data given by the International Organization for Standardization (ISO), and American National Standards Institute (ANSI). In all cases, the mean deviation of the calculated mean conversion coefficients values do not exceed 1% for Hp (0.07,alpha) and 1.5% for Hp (10,alpha), except at 60 degrees where a mean deviation from the ISO values of 1.72% and of 2.27% was, respectively, found. But it is still lower than the mean deviation of 2.31% for Hp(0.07,alpha), and of 3.08% for Hp(10,alpha) observed at this angle between ISO and ANSI values. Otherwise, the computed values of conversion coefficients of H*(10) differ by only 0.41% from the ISO values. The results of this computation method can be considered satisfactory considering the accuracy required in radioprotection fields, and can allow an appreciable estimation of conversion coefficients for the narrow x-ray spectra indispensable to calibrate the personnel dosimeters in terms of the personal dose equivalent.

  18. Bag breakup of low viscosity drops in the presence of a continuous air jet

    SciTech Connect

    Kulkarni, V. Sojka, P. E.

    2014-07-15

    This work examines the breakup of a single drop of various low viscosity fluids as it deforms in the presence of continuous horizontal air jet. Such a fragmentation typically occurs after the bulk liquid has disintegrated upon exiting the atomizer and is in the form of an ensemble of drops which undergo further breakup. The drop deformation and its eventual disintegration is important in evaluating the efficacy of a particular industrial process, be it combustion in automobile engines or pesticide spraying in agricultural applications. The interplay between competing influences of surface tension and aerodynamic disruptive forces is represented by the Weber number, We, and Ohnesorge number, Oh, and used to describe the breakup morphology. The breakup pattern considered in our study corresponds to that of a bag attached to a toroidal ring which occurs from ∼12 < We < ∼16. We aim to address several issues connected with this breakup process and their dependence on We and Oh which have been hitherto unexplored. The We boundary at which breakup begins is theoretically determined and the expression obtained, We=12(1+2/3Oh{sup 2}), is found to match well with experimental data ([L.-P. Hsiang and G. M. Faeth, Int. J. Multiphase Flow 21(4), 545–560 (1995)] and [R. S. Brodkey, “Formation of drops and bubbles,” in The Phenomena of Fluid Motions (Addison-Wesley, Reading, 1967)]). An exponential growth in the radial extent of the deformed drop and the streamline dimension of the bag is predicted by a theoretical model and confirmed by experimental findings. These quantities are observed to strongly depend on We. However, their dependence on Oh is weak.

  19. 75 FR 60493 - Advisory Circular 120-79A, Developing and Implementing an Air Carrier Continuing Analysis and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-30

    ... (AC) 120-79A, ``Developing and Implementing an Air Carrier Continuing Analysis and Surveillance System''. This new advisory circular (AC) updates AC 120-79 originally issued on April 21, 2003. This new AC... . SUPPLEMENTARY INFORMATION: How To Obtain Copies: You can read or download this AC from the Internet at...

  20. Alpha B-crystallin prevents the arrhythmogenic effects of particulate matter isolated from ambient air by attenuating oxidative stress

    SciTech Connect

    Park, Hyelim; Park, Sanghoon; Jeon, Hyunju; Song, Byeong-Wook; Kim, Jin-Bae; Kim, Chang-Soo; Pak, Hui-Nam; Hwang, Ki-Chul; Lee, Moon-Hyoung; Chung, Ji Hyung; Joung, Boyoung

    2013-01-15

    Ca{sup 2+}/calmodulin-dependent protein kinase II (CaMKII) is activated by particulate matter (PM) isolated from ambient air and linked to prolonged repolarization and cardiac arrhythmia. We evaluated whether alpha B-crystallin (CryAB), a heat shock protein, could prevent the arrhythmogenic effects of PM by preventing CaMKII activation. CryAB was delivered into cardiac cells using a TAT-protein transduction domain (TAT-CryAB). ECGs were measured before and after tracheal exposure of diesel exhaust particles (DEP) and each intervention in adult Sprague–Dawley rats. After endotracheal exposure of DEP (200 μg/mL for 30 minutes, n = 11), QT intervals were prolonged from 115 ± 14 ms to 144 ± 20 ms (p = 0.03), and premature ventricular contractions were observed more frequently (0% vs. 44%) than control (n = 5) and TAT-Cry (n = 5). However, DEP-induced arrhythmia was not observed in TAT-CryAB (1 mg/kg) pretreated rats (n = 5). In optical mapping of Langendorff-perfused rat heats, compared with baseline, DEP infusion of 12.5 μg/mL (n = 12) increased apicobasal action potential duration (APD) differences from 2 ± 6 ms to 36 ± 15 ms (p < 0.001), APD restitution slope from 0.26 ± 0.07 to 1.19 ± 0.11 (p < 0.001) and ventricular tachycardia (VT) from 0% to 75% (p < 0.001). DEP infusion easily induced spatially discordant alternans. However, the effects of DEP were prevented by TAT-CryAB (1 mg/kg, n = 9). In rat myocytes, while DEP increased reactive oxygen species (ROS) generation and phosphated CaMKII, TAT-CryAB prevented these effects. In conclusion, CryAB, a small heat shock protein, might prevent the arrhythmogenic effects of PM by attenuating ROS generation and CaMKII activation. -- Highlights: ► Particulate matter (PM) increases arrhythmia. ► PM induced arrhythmias are related with oxidative stress and CaMKII activation. ► Alpha B-crystallin (CryAB) could attenuate the arrhythmogenic effect of PM. ► CryAB decreases oxidative stress and CaMKII activation

  1. Community Air Sensor Network (CAIRSENSE) Project: Lower Cost, Continuous Ambient Monitoring Methods

    EPA Science Inventory

    Advances in air pollution sensor technology have enabled the development of small and low cost systems to measure outdoor air pollution. The deployment of numerous sensors across a small geographic area would have potential benefits to supplement existing monitoring networks and ...

  2. Environmental continuous air monitor inlet with combined preseparator and virtual impactor

    DOEpatents

    Rodgers, John C.

    2007-06-19

    An inlet for an environmental air monitor is described wherein a pre-separator interfaces with ambient environment air and removes debris and insects commonly associated with high wind outdoors and a deflector plate in communication with incoming air from the pre-separator stage, that directs the air radially and downward uniformly into a plurality of accelerator jets located in a manifold of a virtual impactor, the manifold being cylindrical and having a top, a base, and a wall, with the plurality of accelerator jets being located in the top of the manifold and receiving the directed air and accelerating directed air, thereby creating jets of air penetrating into the manifold, where a major flow is deflected to the walls of the manifold and extracted through ports in the walls. A plurality of receiver nozzles are located in the base of the manifold coaxial with the accelerator jets, and a plurality of matching flow restrictor elements are located in the plurality of receiver nozzles for balancing and equalizing the total minor flow among all the plurality of receiver nozzles, through which a lower, fractional flow extracts large particle constituents of the air for collection on a sample filter after passing through the plurality of receiver nozzles and the plurality of matching flow restrictor elements.

  3. Insect hygroreceptor responses to continuous changes in humidity and air pressure.

    PubMed

    Tichy, H; Kallina, W

    2010-06-01

    The most favored model of humidity transduction views the cuticular wall of insect hygroreceptive sensilla as a hygromechanical transducer. Hygroscopic swelling or shrinking alters the geometry of the wall, deforming the dendritic membranes of the moist and dry cells. The small size the sensilla and their position surrounded by elevated structures creates technical difficulties to mechanically stimulate them by direct contact. The present study investigated hygroreceptors on the antennae of the cockroach and the stick insect. Accurately controlled, homogeneous mechanical input was delivered by modulating air pressure. Both the moist and dry cells responded not only to changes in air pressure but also in the opposite direction, as observed during changes in air humidity. The moist cell's excitatory response to increasing humidity and increasing air pressure implies that swelling of the hygroscopic cuticle compresses the dendrites, and the dry cell's excitatory response to decreasing humidity and decreasing air pressure implies that shrinking of the hygroscopic cuticle expands the dendrites. The moist and dry cells of the stick insect are more sensitive to pressure changes than those of the cockroach, but the responses to air pressure are generally weaker than to humidity. Therefore the hygroreceptive sensilla differ in their physical properties and constitutions. Furthermore, the mechanical parameters associated with homogeneous changes in air pressure on the sensillum surface can only partially account for the responses of the moist and dry cells of both species to humidity stimulation. PMID:20375249

  4. Phase characteristic analysis of continuous depth air-gun source wavelet

    NASA Astrophysics Data System (ADS)

    Xing, Lei; Liu, Huaishan; Zheng, Xilai; Liu, Xueqin; Zhang, Jin; Wang, Linfei; Zou, Zhihui; Xu, Yiming

    2016-10-01

    Air guns are important sources for marine seismic exploration. Far-field wavelet of air gun arrays, as a necessary parameter for pre-stack processing and source models, plays an important role during marine seismic data processing and interpretation. When an air gun fires, it generates a series of air bubbles. Similar to onshore seismic exploration, the water forms a plastic fluid near the bubble; the farther the air gun is located from the measurement, the more steady and more accurately represented the wavelet will be. In practice, hydrophones should be placed more than 100 m from the air gun; however, traditional seismic cables cannot meet this requirement. On the other hand, vertical cables provide a viable solution to this problem. This study uses a vertical cable to receive wavelets from 38 air guns and data are collected offshore Southeast Qiong, where the water depth is over 1000 m. In this study, the wavelets measured using this technique coincide very well with the simulated wavelets and can therefore represent the real shape of the wavelets. This experiment fills a technology gap in China.

  5. Insect hygroreceptor responses to continuous changes in humidity and air pressure

    PubMed Central

    Tichy, H.; Kallina, W.

    2011-01-01

    The most favored model of humidity transduction views the cuticular wall of insect hygroreceptive sensilla as a hygromechanical transducer. Hygroscopic swelling or shrinking alters the geometry of the wall, deforming the dendritic membranes of the moist and dry cells. The small size the sensilla and their position surrounded by elevated structures creates technical difficulties to mechanically stimulate them by direct contact. The present study investigated hygroreceptors on the antennae of the cockroach and the stick insect. Accurately controlled, homogeneous mechanical input was delivered by modulating air pressure. Both the moist and dry cells responded not only to changes in air pressure, but also in the opposite direction, as observed during changes in air humidity. The moist-cell’s excitatory response to increasing humidity and increasing air pressure implies that swelling of the hygroscopic cuticle compresses the dendrites, and the dry-cell’s excitatory response to decreasing humidity and decreasing air pressure implies that shrinking of the hygroscopic cuticle expands the dendrites. The moist and dry cells of the stick insect are more sensitive to pressure changes than those of the cockroach, but the responses to air pressure are generally weaker than to humidity. Therefore, the hygroreceptive sensilla differ in their physical properties and constitutions. Furthermore, the mechanical parameters associated with homogeneous changes in air pressure on the sensillum surface can only partially account for the responses of the moist and dry cells of both species to humidity stimulation. PMID:20375249

  6. Influences of air calcination and steam activation on microstructure and photocatalytic activity of continuous TiO{sub 2} fibers

    SciTech Connect

    You, Yang; Zhang, Shiying; Xu, Difa

    2013-02-15

    Graphical abstract: Display Omitted Highlights: ► Effects of air calcination and steam activation on TiO{sub 2} fibers were studied. ► The photocatalytic activity was evaluated by degradation of formaldehyde. ► Steam activation promoted the anatase–rutile phase transformation. ► Steam activation decreased grain size and increased special surface area. ► Steam activation improved photocatalytic activity of TiO{sub 2} fibers. -- Abstract: Effects of air calcination and steam activation, on phase transformation, microstructure and photocatalytic activity of continuous TiO{sub 2} fibers prepared by sol–gel method were studied. The fibers were characterized by XRD, SEM, and N{sub 2} adsorption–desorption. The photocatalytic activity was evaluated by photocatalytic degradation of formaldehyde. Results showed that 100% rutile fibers heat-treated in air and steam were obtained at 800 °C and 600 °C, respectively. The anatase grain sizes and special surface areas of the fibers heat-treated at 500 °C in air and steam were 31.6 nm, 22.7 nm, 26.7 m{sup 2}/g and 32.3 m{sup 2}/g, respectively. The degradation rates of formaldehyde over the fibers heat-treated at 500 °C in air and steam were 92.3% and 98.6% after 14 h under UV irradiation, respectively. Compared with the air calcination, the steam activation promoted the anatase–rutile phase transformation, reduced the grain size, increased the special surface area, and improved photocatalytic activity of continuous TiO{sub 2} fibers.

  7. Continuous culture of Plasmodium falciparum asexual stages in "normal" air atmosphere.

    PubMed

    Mirovský, P

    1989-01-01

    The growth of six strains of Plasmodium falciparum in 5% CO2, 5% O2, 90% N2 and normal air atmosphere was determined daily by microscopical examination of blood films. All strains were able to grow in flasks without additional gas mixture but significantly lower parasitaemia was observed within the first five days of cultivation. Attempt at cultivating in petri dishes without candle jar technique failed but parasites survived in plasticine sealed dishes. The cultivation in air cannot be recommended for cultures initiated from cryopreserved material or low parasitaemia (0.1-0.3%) cultures. PMID:2504654

  8. Dry/wet performance of a plate-fin air-cooled heat exchanger with continuous corrugated fins

    SciTech Connect

    Hauser, S.G.; Kreid, D.K.; Johnson, B.M.

    1981-01-01

    The performance and operating characteristics of a plate-fin heat exchanger in dry/wet or deluge operations was experimentally determined. Development of the deluge heat/mass transfer model continued. The experiments were conducted in a specially-designed wind tunnel at the PNL. Air that was first heated and humidified to specified conditions was circulated at a controlled rate through a 2 ft x 6 ft heat exchanger module. The heat exchanger used in the tests was a wavy surface, plate fin on tube configuration. Hot water was circulated through the tubes at high flow rates to maintain an essentially isothermal condition on the tube side. Deionized water sprayed on the top of the vertically oriented plate fins was collected at the bottom of the core and recirculated. Instrumentation was provided for measurement of flow rates and thermodynamic conditions in the air, in the core circulation water, and in the deluge water. Measurements of the air side pressure drop and heat rejection rate were made as a function of air flow rate, air inlet temperature and humidity, deluge water flow rate, and the core inclination from the vertical. An overall heat transfer coefficient and an effective deluge film convective coefficient was determined. The deluge model, for predicting heat transfer from a wet finned heat exchanger was further developed and refined, and a major extension of the model was formulated that permits simultaneous calculation of both the heat transfer and evaporation rates from the wetted surface. The experiments showed an increase in the heat rejection rate due to wetting, accompanied by a proportional increase in the air side pressure drop. For operation at the same air side pressure drop, the enhancement ratio Q/sub w//Q/sub d/ varied between 2 and 5 for the conditions tested. Thus, the potential enhancement of heat transfer due to wetting can be substantial.

  9. Physical and Mathematical Modeling of Thin Steel Slab Continuous Casting Secondary Cooling Zone Air-Mist Impingement

    NASA Astrophysics Data System (ADS)

    de León B., Melecio; Castillejos E., A. Humberto

    2015-10-01

    This study is an attempt to unveil the fluid dynamic phenomena occurring during interaction of air-mists with the surface of the steel strand during its pass through the continuous casting secondary cooling system. Air-mists generated under conditions of practical interest are studied while impacting on a vertical wall at room temperature. Experimentally a spatial multiple-counting technique based on capturing instantaneous double-exposure shadowgraphs is used to visualize the internal structure of mists at distances between 0 and 4 mm from the wall. Analysis of single exposure images allows determination of size distributions of primary (impinging) and secondary (ejecting) drops and of fluctuating thickness of water films formed on the wall surface. Besides, examination of image pairs enables measurement of velocity and trajectory angles of both kinds of drops. These results aided in the formulation and validation of a transient, turbulent, 3D, multiphase fluid dynamic model for simulating impinging air-mists. The model is based on KIVA-3V and for simulating the airborne mist region it solves the continuity equations—mass, momentum, turbulence quantities—for the air coupled with the equation of motion for drops sampled randomly from distributions assumed to govern their size and volume flux at the nozzle orifice. While for the impingement region submodels are established to estimate the results of drop/wall interaction, i.e., the dynamics of secondary drops and water films formed by the impingement of primary drops. The model forecasts reasonably well the random distributions of diameters, velocities, trajectory angles, and Weber numbers of both kind of drops moving near the wall. Additionally, it predicts well the average thickness of the water film and the important effect that air nozzle pressure has on the normal impinging velocity of drops; high pressures result in large drop velocities favoring intimate contact with the surface.

  10. Continuous flow membrane-less air cathode microbial fuel cell with spunbonded olefin diffusion layer.

    PubMed

    Tugtas, Adile Evren; Cavdar, Pelin; Calli, Baris

    2011-11-01

    The power production performance of a membrane-less air-cathode microbial fuel cell was evaluated for 53 days. Anode and cathode electrodes and the micro-fiber cloth separator were configured by sandwiching the separator between two electrodes. In addition, the air-facing side of the cathode was covered with a spunbonded olefin sheet instead of polytetrafluoroethylene (PTFE) coating to control oxygen diffusion and water loss. The configuration resulted in a low resistance of about 4Ω and a maximum power density of 750 mW/m2. However, as a result of a gradual decrease in the cathode potential, maximum power density decreased to 280 mW/m2. The declining power output was attributed to loss of platinum catalyst (8.26%) and biomass growth (38.44%) on the cathode. Coulombic efficiencies over 55% and no water leakage showed that the spunbonded olefin sheet covering the air-facing side of the cathode can be a cost-effective alternative to PTFE coating.

  11. Air humidity may influence the aerosol distribution of normal saline administered by closed or vented nebulizers operated continuously or dosimetrically.

    PubMed

    Krajnik, Malgorzata; Podolec, Zygmunt; Zylicz, Zbigniew; Jassem, Ewa

    2009-03-01

    In clinical practice the majority of inhaled agents require deposition in the most distant regions of the bronchial tree. Contrary to this, it is likely that morphine delivery in breathlessness and chronic cough should be directed to the tracheobronchial area. The aim of the present study was to assess how an environmental condition such as air humidity might influence the particle distribution of normal saline administered by closed or vented nebulizers operated continuously or dosimetrically. Aerosol generated as a saline solution was assessed for BCTSS (Bronchial Control Treatment System-Sidestream) and BCTS-MC (Bronchial Control Treatment System-Micro Cirrus), together with two pneumatic delivery systems: Pneumatic Inhalation-Sidestream (PI-S) and Pneumatic Inhalation-Micro Cirrus (PI-MC). To clarify the influence of humidity on the aerosol we introduced a fifth method, BCTS-S/C, which included a vented nebulizer operated continuously. The impact of different air humidity on the size of particles was examined. Only in the case of the vented methods (BCTS-S and BCTSS/C) of nebulization did air humidifying lead to a significant enlargement of particle size. Moreover, the mean particle size at 90% was almost twice as large with the use of BCTS-S than with BCTS-S/C. Our experiment demonstrated that ambient humidity has a greater effect on particle size with vented rather than nonvented nebulizers and the effect might be potentiated by the pulsative method of nebulization.

  12. Use of sulfur hexafluoride airflow studies to determine the appropriate number and placement of air monitors in an alpha inhalation exposure laboratory

    SciTech Connect

    Newton, G.J.; Hoover, M.D.

    1995-12-01

    Determination of the appropriate number and placement of air monitors in the workplace is quite subjective and is generally one of the more difficult tasks in radiation protection. General guidance for determining the number and placement of air sampling and monitoring instruments has been provided by technical reports such as Mishima, J. These two documents and other published guidelines suggest that some insight into sampler placement can be obtained by conducting airflow studies involving the dilution and clearance of the relatively inert tracer gas sulfur hexafluoride (SF{sub 6}) in sampler placement studies and describes the results of a study done within the ITRI alpha inhalation exposure laboratories. The objectives of the study were to document an appropriate method for conducting SF{sub 6} dispersion studies, and to confirm the appropriate number and placement of air monitors and air samplers within a typical ITRI inhalation exposure laboratory. The results of this study have become part of the technical bases for air sampling and monitoring in the test room.

  13. A fiber air-gap Fabry-Pérot temperature sensor demodulated by using frequency modulated continuous wave

    NASA Astrophysics Data System (ADS)

    Zheng, Wanfu; Xie, Jianglei; Li, Yi; Xu, Ben; Kang, Juan; Shen, Changyu; Wang, Jianfeng; Jin, Yongxing; Liu, Honglin; Ni, Kai; Dong, Xinyong; Zhao, Chunliu; Jin, Shangzhong

    In this study, a fiber in-line air-gap Fabry-Pérot interferometer (FPI) is fabricated by HF acid etching. For a low-cost and higher precise measurement, a demodulation system based on frequency modulated continuous wave (FMCW) technique is build up and demonstrated in this air-gap FPI. In temperature measurements, the temperature sensitivity is about 1.75 rad/°C by phase shift detection. We also test the long term performance of the system and the RMS error is about 0.04 rad, which corresponds to the temperature resolution of ~0.02 °C. It is much higher than the measurement resolution by using the traditional wavelength shift detection method. Our experiments show that the FMCW can provide a low-cost, high resolution and high speed interrogation solution to the fiber FPIs.

  14. Evaluation of the Impact of Media Marketing Strategies on Continuing Education Enrollments. AIR Forum 1982 Paper.

    ERIC Educational Resources Information Center

    Campbell, Jill F.; Spiro, Louis M.

    The impact of media marketing strategies on continuing education enrollment at the State University of New York College at Brockport (SUNY-CB), was evaluated. The evaluation of advertising impacts used advertising records of SUNY-CB and other area colleges and a telephone questionnaire instrument. A stratified, random countywide sample, in…

  15. A model for treating polluted air streams in a continuous two liquid phase stirred tank bioreactor.

    PubMed

    Fazaelipoor, Mohammad Hassan

    2007-09-01

    Biological air treatment systems have been widely under investigation in recent years. Inclusion of non-biodegradable organic solvents to these systems is a way to improve the biotic removal capacity of the systems. In this article the process of absorption and biodegradation of a hydrophobic organic compound in a two liquid phase stirred tank bioreactor has been modeled. Using the model it has been shown that the inclusion of an organic solvent is advantageous if certain conditions are met. Some simulation examples showed that the usefulness of adding an organic solvent to the system depends on kinetic parameters of biological reactions and mass transfer coefficients of pollutants and oxygen between the air and liquid phases. Since different factors influence the process, the usefulness of including an organic solvent to the system should be checked in each special case. The simple model presented in this article can help the prediction of the effect of amending a solvent to the bioreactor under a set of given conditions.

  16. Pulling Results Out of Thin Air: Four Years of Ozone and Greenhouse Gas Measurements by the Alpha Jet Atmospheric Experiment (AJAX)

    NASA Technical Reports Server (NTRS)

    Yates, Emma

    2015-01-01

    The Alpha Jet Atmospheric eXperiment (AJAX) has been measuring atmospheric ozone, carbon dioxide, methane and meteorological parameters from near the surface to 8000 m since January 2011. The main goals are to study photochemical ozone production and the impacts of extreme events on western US air quality, provide data to support satellite observations and aid in the quantification of emission sources e.g. wildfires, urban outflow, diary and oil and gas. The aircraft is based at Moffett Field and flies multiple times a month to sample vertical profiles at selected sites in California and Nevada, providing long-term data records at these sites. AJAX is also uniquely positioned to launch with short notice sampling flights in rapid response to extreme events e.g. the 2013 Yosemite Rim fire. This talk will focus on the impacts of vertical transport on surface air quality, and investigation of emission sources from diaries and wildfires.

  17. [Study on immobilized cells for producing alpha-amylase by using polyving alcohol as the carrier(II): The effect of fermentating conditions on the ability producing alpha-amylase of the cells immobilized with polyving alcohol as the corrier and continuous fermentation of the immobilized cells in CSTR].

    PubMed

    Liu, Z; Wang, J; Li, Z

    1998-03-01

    The effects of fermentating conditions on the ability of immobilized cells with PVA as carrier for producing alpha-amylase were studied. The continuous fermentation with the immobilized cells were tested in continuous flow stirred tank reactor (CSTR). The results showed that the adaptability of the immobilized Bacillus substilis to pH increased after immobilization. In CSTR, the immobilized cells can be fermentated continuously for 360 hrs and the activity of alpha-amylase can be kept on the level of about 170 u/ml.

  18. Detection of Campylobacter Bacteria in Air Samples for Continuous Real-Time Monitoring of Campylobacter Colonization in Broiler Flocks▿

    PubMed Central

    Olsen, Katja N.; Lund, Marianne; Skov, Julia; Christensen, Laurids S.; Hoorfar, Jeffrey

    2009-01-01

    Improved monitoring tools are important for the control of Campylobacter bacteria in broiler production. In this study, we compare the sensitivities of detection of Campylobacter by PCR with feces, dust, and air samples during the lifetimes of broilers in two poultry houses and conclude that the sensitivity of detection of Campylobacter in air is comparable to that in other sample materials. Profiling of airborne particles in six poultry houses revealed that the aerodynamic conditions were dependent on the age of the chickens and very comparable among different poultry houses, with low proportions of particles in the 0.5- to 2-μm-diameter range and high proportions in the 2- to 5-μm-diameter range. Campylobacter could also be detected by PCR in air samples collected at the hanging stage during the slaughter process but not at the other stages tested at the slaughterhouse. The exploitation of airborne dust in poultry houses as a sample material for the detection of Campylobacter and other pathogens provides an intriguing possibility, in conjunction with new detection technologies, for allowing continuous or semicontinuous monitoring of colonization status. PMID:19201953

  19. Detection of Campylobacter bacteria in air samples for continuous real-time monitoring of Campylobacter colonization in broiler flocks.

    PubMed

    Olsen, Katja N; Lund, Marianne; Skov, Julia; Christensen, Laurids S; Hoorfar, Jeffrey

    2009-04-01

    Improved monitoring tools are important for the control of Campylobacter bacteria in broiler production. In this study, we compare the sensitivities of detection of Campylobacter by PCR with feces, dust, and air samples during the lifetimes of broilers in two poultry houses and conclude that the sensitivity of detection of Campylobacter in air is comparable to that in other sample materials. Profiling of airborne particles in six poultry houses revealed that the aerodynamic conditions were dependent on the age of the chickens and very comparable among different poultry houses, with low proportions of particles in the 0.5- to 2-microm-diameter range and high proportions in the 2- to 5-microm-diameter range. Campylobacter could also be detected by PCR in air samples collected at the hanging stage during the slaughter process but not at the other stages tested at the slaughterhouse. The exploitation of airborne dust in poultry houses as a sample material for the detection of Campylobacter and other pathogens provides an intriguing possibility, in conjunction with new detection technologies, for allowing continuous or semicontinuous monitoring of colonization status.

  20. Long range alpha particle detector

    DOEpatents

    MacArthur, D.W.; Wolf, M.A.; McAtee, J.L.; Unruh, W.P.; Cucchiara, A.L.; Huchton, R.L.

    1993-02-02

    An alpha particle detector capable of detecting alpha radiation from distant sources. In one embodiment, a high voltage is generated in a first electrically conductive mesh while a fan draws air containing air molecules ionized by alpha particles through an air passage and across a second electrically conductive mesh. The current in the second electrically conductive mesh can be detected and used for measurement or alarm. The detector can be used for area, personnel and equipment monitoring.

  1. Long range alpha particle detector

    DOEpatents

    MacArthur, Duncan W.; Wolf, Michael A.; McAtee, James L.; Unruh, Wesley P.; Cucchiara, Alfred L.; Huchton, Roger L.

    1993-01-01

    An alpha particle detector capable of detecting alpha radiation from distant sources. In one embodiment, a high voltage is generated in a first electrically conductive mesh while a fan draws air containing air molecules ionized by alpha particles through an air passage and across a second electrically conductive mesh. The current in the second electrically conductive mesh can be detected and used for measurement or alarm. The detector can be used for area, personnel and equipment monitoring.

  2. Direct, Continuous Monitoring of Air Pollution by Transgenic Sensor Mice Responsive to Halogenated and Polycyclic Aromatic Hydrocarbons

    PubMed Central

    Kasai, Ayumi; Hiramatsu, Nobuhiko; Hayakawa, Kunihiro; Yao, Jian; Kitamura, Masanori

    2008-01-01

    Background The aryl hydrocarbon receptor (AhR, also called the dioxin receptor) plays crucial roles in toxicologic responses of animals to environmental pollutants, especially to halogenated and polycyclic aromatic hydrocarbons. To achieve direct, continuous risk assessment of air pollution using biological systems, we generated transgenic sensor mice that produce secreted alkaline phosphatase (SEAP) under the control of AhR. Methods To characterize responses of the mice to AhR agonists, sensor mice were orally administered 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3-methylcholanthrene (3MC), benzo[a]pyrene (B[a]P), or β-naphthoflavone (BNF), and serum levels of SEAP were evaluated. To monitor air pollution caused by cigarette smoke, we placed the mice each day in an experimental smoking room, and evaluated activity of serum SEAP for up to 4 days. Activation of AhR in individual organs was also examined by reverse transcription–polymerase chain reaction (RT-PCR) analysis of SEAP. Results In response to oral exposure to TCDD, sensor mice exhibited dramatic and sustained activation of AhR. The mice also responded sensitively to 3MC, B[a]P, and BNF. Activation of AhR was dose dependent, and the liver was identified as the main responding organ. After exposure to the smoking environment, sensor mice consistently exhibited transient, reversible activation of AhR. RT-PCR analysis of SEAP revealed that activation of AhR occurred predominantly in the lung. Conclusion We are the first laboratory to demonstrate successfully direct, comprehensive monitoring of air pollution using genetically engineered mammals. The established system would be useful for real risk assessment of halogenated and polycyclic aromatic hydrocarbons in the air, especially in smoking environments. PMID:18335102

  3. Continuous droplet removal upon dropwise condensation of humid air on a hydrophobic micropatterned surface.

    PubMed

    Zamuruyev, Konstantin O; Bardaweel, Hamzeh K; Carron, Christopher J; Kenyon, Nicholas J; Brand, Oliver; Delplanque, Jean-Pierre; Davis, Cristina E

    2014-08-26

    Combination of two physical phenomena, capillary pressure gradient and wettability gradient, allows a simple two-step fabrication process that yields a reliable hydrophobic self-cleaning condenser surface. The surface is fabricated with specific microscopic topography and further treatment with a chemically inert low-surface-energy material. This process does not require growth of nanofeatures (nanotubes) or hydrophilic-hydrophobic patterning of the surface. Trapezoidal geometry of the microfeatures facilitates droplet transfer from the Wenzel to the Cassie state and reduces droplet critical diameter. The geometry of the micropatterns enhances local coalescence and directional movement for droplets with diameter much smaller than the radial length of the micropatterns. The hydrophobic self-cleaning micropatterned condenser surface prevents liquid film formation and promotes continuous dropwise condensation cycle. Upon dropwise condensation, droplets follow a designed wettability gradient created with micropatterns from the most hydrophobic to the least hydrophobic end of the surface. The surface has higher condensation efficiency, due to its directional self-cleaning property, than a plain hydrophobic surface. We explain the self-actuated droplet collection mechanism on the condenser surface and demonstrate experimentally the creation of an effective wettability gradient over a 6 mm radial distance. In spite of its fabrication simplicity, the fabricated surface demonstrates self-cleaning property, enhanced condensation performance, and reliability over time. Our work enables creation of a hydrophobic condenser surface with the directional self-cleaning property that can be used for collection of biological (chemical, environmental) aerosol samples or for condensation enhancement.

  4. Continuous Droplet Removal upon Dropwise Condensation of Humid Air on a Hydrophobic Micropatterned Surface

    PubMed Central

    2015-01-01

    Combination of two physical phenomena, capillary pressure gradient and wettability gradient, allows a simple two-step fabrication process that yields a reliable hydrophobic self-cleaning condenser surface. The surface is fabricated with specific microscopic topography and further treatment with a chemically inert low-surface-energy material. This process does not require growth of nanofeatures (nanotubes) or hydrophilic–hydrophobic patterning of the surface. Trapezoidal geometry of the microfeatures facilitates droplet transfer from the Wenzel to the Cassie state and reduces droplet critical diameter. The geometry of the micropatterns enhances local coalescence and directional movement for droplets with diameter much smaller than the radial length of the micropatterns. The hydrophobic self-cleaning micropatterned condenser surface prevents liquid film formation and promotes continuous dropwise condensation cycle. Upon dropwise condensation, droplets follow a designed wettability gradient created with micropatterns from the most hydrophobic to the least hydrophobic end of the surface. The surface has higher condensation efficiency, due to its directional self-cleaning property, than a plain hydrophobic surface. We explain the self-actuated droplet collection mechanism on the condenser surface and demonstrate experimentally the creation of an effective wettability gradient over a 6 mm radial distance. In spite of its fabrication simplicity, the fabricated surface demonstrates self-cleaning property, enhanced condensation performance, and reliability over time. Our work enables creation of a hydrophobic condenser surface with the directional self-cleaning property that can be used for collection of biological (chemical, environmental) aerosol samples or for condensation enhancement. PMID:25073014

  5. Efficient salt removal in a continuously operated upflow microbial desalination cell with an air cathode.

    PubMed

    Jacobson, Kyle S; Drew, David M; He, Zhen

    2011-01-01

    Microbial desalination cells (MDCs) hold great promise for drinking water production because of potential energy savings during the desalination process. In this study, we developed a continuously operated MDC--upflow microbial desalination cell (UMDC) for the purpose of salt removal. During the 4-month operation, the UMDC constantly removed salts and generated bio-electricity. At a hydraulic retention time (HRT) of 4 days (salt solution) and current production of ∼62 mA, the UMDC was able to remove more than 99% of NaCl from the salt solution that had an initial salt concentration of 30 g total dissolved solids (TDS)/L. In addition, the TDS removal rate was 7.50 g TDSL(-1)d(-1) (salt solution volume) or 5.25 g TDSL(-1)d(-1) (wastewater volume), and the desalinated water met the drinking water standard, in terms of TDS concentration. A high charge transfer efficiency of 98.6% or 81% was achieved at HRT 1 or 4d. The UMDC produced a maximum power density of 30.8 W/m(3). The phenomena of bipolar electrodialysis and proton transport in the UMDC were discussed. These results demonstrated the potential of the UMDC as either a sole desalination process or a pre-desalination reactor for downstream desalination processes.

  6. First continuous measurements of δ18O-CO2 in air with a Fourier transform infrared spectrometer

    NASA Astrophysics Data System (ADS)

    Vardag, S. N.; Hammer, S.; Sabasch, M.; Griffith, D. W. T.; Levin, I.

    2015-02-01

    The continuous in situ measurement of δ18O in atmospheric CO2 opens a new door to differentiating between CO2 source and sink components with high temporal resolution. Continuous 13C-CO2 measurement systems have already been commercially available for some time, but until now, only few instruments have been able to provide a continuous measurement of the oxygen isotope ratio in CO2. Besides precise 13C/12C observations, the Fourier transform infrared (FTIR) spectrometer is also able to measure the 18O / 16O ratio in CO2, but the precision and accuracy of the measurements have not yet been evaluated. Here we present a first analysis of δ18O-CO2 (and δ13C-CO2) measurements with the FTIR analyser in Heidelberg. We used Allan deviation to determine the repeatability of δ18O-CO2 measurements and found that it decreases from 0.25‰ for 10 min averages to about 0.1‰ after 2 h and remains at that value up to 24 h. We evaluated the measurement precision over a 10-month period (intermediate measurement precision) using daily working gas measurements and found that our spectrometer measured δ18O-CO2 to better than 0.3‰ at a temporal resolution of less than 10 min. The compatibility of our FTIR-spectrometric measurements to isotope-ratio mass-spectrometric (IRMS) measurements was determined by comparing FTIR measurements of cylinder gases and ambient air with IRMS measurements of flask samples, filled with gases of the same cylinders or collected from the same ambient air intake. Two-sample t tests revealed that, at the 0.01 significance level, the FTIR and the IRMS measurements do not differ significantly from each other and are thus compatible. We describe two weekly episodes of ambient air measurements, one in winter and one in summer, and discuss what potential insights and new challenges combined highly resolved CO2, δ13C-CO2 and δ18O-CO2 records may provide in terms of better understanding regional scale continental carbon exchange processes.

  7. Size and Velocity Characteristics of Droplets Generated by Thin Steel Slab Continuous Casting Secondary Cooling Air-Mist Nozzles

    NASA Astrophysics Data System (ADS)

    Minchaca M, J. I.; Castillejos E, A. H.; Acosta G, F. A.

    2011-06-01

    Direct spray impingement of high temperature surfaces, 1473 K to 973 K (1200 °C to 700 °C), plays a critical role in the secondary cooling of continuously cast thin steel slabs. It is known that the spray parameters affecting the local heat flux are the water impact flux w as well as the droplet velocity and size. However, few works have been done to characterize the last two parameters in the case of dense mists ( i.e., mists with w in the range of 2 to 90 L/m2s). This makes it difficult to rationalize how the nozzle type and its operating conditions must be selected to control the cooling process. In the present study, particle/droplet image analysis was used to determine the droplet size and velocity distributions simultaneously at various locations along the major axis of the mist cross section at a distance where the steel strand would stand. The measurements were carried out at room temperature for two standard commercial air-assisted nozzles of fan-discharge type operating over a broad range of conditions of practical interest. To achieve statistically meaningful samples, at least 6000 drops were analyzed at each location. Measuring the droplet size revealed that the number and volume frequency distributions were fitted satisfactorily by the respective log-normal and Nukiyama-Tanasawa distributions. The correlation of the parameters of the distribution functions with the water- and air-nozzle pressures allowed for reasonable estimation of the mean values of the size of the droplets generated. The ensemble of measurements across the mist axis showed that the relationship between the droplet velocity and the diameter exhibited a weak positive correlation. Additionally, increasing the water flow rate at constant air pressure caused a decrease in the proportion of the water volume made of finer droplets, whereas the volume proportion of faster droplets augmented until the water flow reached a certain value, after which it decreased. Diminishing the air

  8. [Hearing loss by continuous exposure to high sound pressure among maintenance workers at a Brazilian Air Force helicopters unity].

    PubMed

    Ribeiro, Ana Maria Dutra; Câmara, Volney de M

    2006-06-01

    Continuous exposure to high sound pressure in aeronautical workers can be associated with inner ear hearing loss. This study aims to evaluate the prevalence of deafness among all maintenance workers from a Brazilian Air Force helicopter unit. The methods included the application of individual questionnaires and audiometric tests. The results showed a high prevalence (32.4%) of hearing loss related to time on the job (p < 0.05; RP = 2.11; 95%CI: 1.03-4.32) and the 41-50-year age bracket (p = 0.00; RP < 3.94; 95%CI: 2.04-7.62). No influence was found from selected variables that might result in bias. Finally, a program to prevent hearing loss was recommended.

  9. Experimental und numerical investigations on cooling efficiency of Air-Mist nozzles on steel during continuous casting

    NASA Astrophysics Data System (ADS)

    Arth, G.; Taferner, M.; Bernhard, C.; Michelic, S.

    2016-07-01

    Cooling strategies in continuous casting of steel can vary from rapid cooling to slow cooling, mainly controlled by adjusting the amount of water sprayed onto the surface of the product. Inadequate adjustment however can lead to local surface undercooling or reheating, leading to surface and inner defects. This paper focuses on cooling efficiency of Air-Mist nozzles on casted steel and the experimental and numerical prediction of surface temperature distributions over the product width. The first part explains the determination of heat transfer coefficients (HTC) on laboratory scale, using a so called nozzle measuring stand (NMS). Based on measured water distributions and determined HTC's for air-mist nozzles using the NMS, surface temperatures are calculated by a transient 2D-model on a simple steel plate, explained in the second part of this paper. Simulations are carried out varying water impact density and spray water distribution, consequently influencing the local HTC distribution over the plate width. Furthermore, these results will be interpreted with regard to their consequence for surface and internal quality of the cast product. The results reveal the difficulty of correct adjustment of the amount of sprayed water, concurrent influencing water distribution and thus changing HTC distribution and surface temperature.

  10. Diamond detector for alpha-particle spectrometry.

    PubMed

    Dueñas, J A; de la Torre Pérez, J; Martín Sánchez, A; Martel, I

    2014-08-01

    An artificially grown high purity diamond was used as a detector for alpha-particle spectrometry. Diamond detectors can match the performance of silicon detectors employed in standard continuous air monitoring systems. Its radiation hardness and electronic properties make them ideal to work under extreme condition such as high temperature and ambient lights. A 50 μm thickness single-crystal diamond detector has been compared with a 300 μm passivated implanted planar silicon detector, under ambient conditions.

  11. Prototype development and test results of a continuous ambient air monitoring system for hydrazine at the 10 ppb level

    NASA Astrophysics Data System (ADS)

    Meneghelli, Barry; Parrish, Clyde; Barile, Ron; Lueck, Dale E.

    1995-01-01

    A Hydrazine Vapor Area Monitor (HVAM) system is currently being field tested as a detector for the presence of hydrazine in ambient air. The MDA/Polymetron Hydrazine Analyzer has been incorporated within the HVAM system as the core detector. This analyzer is a three-electrode liquid analyzer typically used in boiler feed water applications. The HVAM system incorporates a dual-phase sample collection/transport method which simultaneously pulls ambient air samples containing hydrazine and a very dilute sulfuric acid solution (0.0001 M) down a length of 1/4 inch outside diameter (OD) tubing from a remote site to the analyzer. The hydrazine-laden dilute acid stream is separated from the air and the pH is adjusted by addition of a dilute caustic solution to a pH greater than 10.2 prior to analysis. Both the dilute acid and caustic used by the HVAM are continuously generated during system operation on an "as needed" basis by mixing a metered amount of concentrated acid/base with dilution water. All of the waste water generated by the analyzer is purified for reuse by Barnstead ion-exchange cartridges so that the entire system minimizes the generation of waste materials. The pumping of all liquid streams and mixing of the caustic solution and dilution water with the incoming sample are done by a single pump motor fitted with the appropriate mix of peristaltic pump heads. The signal to noise (S/N) ratio of the analyzer has been enhanced by adding a stirrer in the MDA liquid cell to provide mixing normally generated by the high liquid flow rate designed by the manufacturer. An onboard microprocessor continuously monitors liquid levels, sample vacuum, and liquid leak sensors, as well as handles communications and other system functions (such as shut down should system malfunctions or errors occur). The overall system response of the HVAM can be automatically checked at regular intervals by measuring the analyzer response to a metered amount of calibration standard injected

  12. Prototype development and test results of a continuous ambient air monitoring system for hydrazine at the 10 ppb level

    NASA Technical Reports Server (NTRS)

    Meneghelli, Barry; Parrish, Clyde; Barile, Ron; Lueck, Dale E.

    1995-01-01

    A Hydrazine Vapor Area Monitor (HVAM) system is currently being field tested as a detector for the presence of hydrazine in ambient air. The MDA/Polymetron Hydrazine Analyzer has been incorporated within the HVAM system as the core detector. This analyzer is a three-electrode liquid analyzer typically used in boiler feed water applications. The HVAM system incorporates a dual-phase sample collection/transport method which simultaneously pulls ambient air samples containing hydrazine and a very dilute sulfuric acid solution (0.0001 M) down a length of 1/4 inch outside diameter (OD) tubing from a remote site to the analyzer. The hydrazine-laden dilute acid stream is separated from the air and the pH is adjusted by addition of a dilute caustic solution to a pH greater than 10.2 prior to analysis. Both the dilute acid and caustic used by the HVAM are continuously generated during system operation on an "as needed" basis by mixing a metered amount of concentrated acid/base with dilution water. All of the waste water generated by the analyzer is purified for reuse by Barnstead ion-exchange cartridges so that the entire system minimizes the generation of waste materials. The pumping of all liquid streams and mixing of the caustic solution and dilution water with the incoming sample are done by a single pump motor fitted with the appropriate mix of peristaltic pump heads. The signal to noise (S/N) ratio of the analyzer has been enhanced by adding a stirrer in the MDA liquid cell to provide mixing normally generated by the high liquid flow rate designed by the manufacturer. An onboard microprocessor continuously monitors liquid levels, sample vacuum, and liquid leak sensors, as well as handles communications and other system functions (such as shut down should system malfunctions or errors occur). The overall system response of the HVAM can be automatically checked at regular intervals by measuring the analyzer response to a metered amount of calibration standard injected

  13. Discontinuous and Continuous Indoor Air Quality Monitoring in Homes with Fireplaces or Wood Stoves as Heating System.

    PubMed

    de Gennaro, Gianluigi; Dambruoso, Paolo Rosario; Di Gilio, Alessia; Di Palma, Valerio; Marzocca, Annalisa; Tutino, Maria

    2015-12-24

    Around 50% of the world's population, particularly in developing countries, uses biomass as one of the most common fuels. Biomass combustion releases a considerable amount of various incomplete combustion products, including particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs). The paper presents the results of Indoor Air Quality (IAQ) measurements in six houses equipped with wood burning stoves or fireplaces as heating systems. The houses were monitored for 48-h periods in order to collect PM10 samples and measure PAH concentrations. The average, the maximum and the lowest values of the 12-h PM10 concentration were 68.6 μg/m³, 350.7 μg/m³ and 16.8 μg/m³ respectively. The average benzo[a]pyrene 12-h concentration was 9.4 ng/m³, while the maximum and the minimum values were 24.0 ng/m³ and 1.5 ng/m³, respectively. Continuous monitoring of PM10, PAHs, Ultra Fine Particle (UFP) and Total Volatile Organic Compounds (TVOC) was performed in order to study the progress of pollution phenomena due to biomass burning, their trends and contributions to IAQ. The results show a great heterogeneity of impacts on IAQ in terms of magnitude and behavior of the considered pollutants' concentrations. This variability is determined by not only different combustion technologies or biomass quality, but overall by different ignition mode, feeding and flame management, which can also be different for the same house. Moreover, room dimensions and ventilation were significant factors for pollution dispersion. The increase of PM10, UFP and PAH concentrations, during lighting, was always detected and relevant. Continuous monitoring allowed singling out contributions of other domestic sources of considered pollutants such as cooking and cigarettes. Cooking contribution produced an impact on IAQ in same cases higher than that of the biomass heating system.

  14. Discontinuous and Continuous Indoor Air Quality Monitoring in Homes with Fireplaces or Wood Stoves as Heating System

    PubMed Central

    de Gennaro, Gianluigi; Dambruoso, Paolo Rosario; Di Gilio, Alessia; Di Palma, Valerio; Marzocca, Annalisa; Tutino, Maria

    2015-01-01

    Around 50% of the world’s population, particularly in developing countries, uses biomass as one of the most common fuels. Biomass combustion releases a considerable amount of various incomplete combustion products, including particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs). The paper presents the results of Indoor Air Quality (IAQ) measurements in six houses equipped with wood burning stoves or fireplaces as heating systems. The houses were monitored for 48-h periods in order to collect PM10 samples and measure PAH concentrations. The average, the maximum and the lowest values of the 12-h PM10 concentration were 68.6 μg/m3, 350.7 μg/m3 and 16.8 μg/m3 respectively. The average benzo[a]pyrene 12-h concentration was 9.4 ng/m3, while the maximum and the minimum values were 24.0 ng/m3 and 1.5 ng/m3, respectively. Continuous monitoring of PM10, PAHs, Ultra Fine Particle (UFP) and Total Volatile Organic Compounds (TVOC) was performed in order to study the progress of pollution phenomena due to biomass burning, their trends and contributions to IAQ. The results show a great heterogeneity of impacts on IAQ in terms of magnitude and behavior of the considered pollutants’ concentrations. This variability is determined by not only different combustion technologies or biomass quality, but overall by different ignition mode, feeding and flame management, which can also be different for the same house. Moreover, room dimensions and ventilation were significant factors for pollution dispersion. The increase of PM10, UFP and PAH concentrations, during lighting, was always detected and relevant. Continuous monitoring allowed singling out contributions of other domestic sources of considered pollutants such as cooking and cigarettes. Cooking contribution produced an impact on IAQ in same cases higher than that of the biomass heating system. PMID:26712773

  15. Discontinuous and Continuous Indoor Air Quality Monitoring in Homes with Fireplaces or Wood Stoves as Heating System.

    PubMed

    de Gennaro, Gianluigi; Dambruoso, Paolo Rosario; Di Gilio, Alessia; Di Palma, Valerio; Marzocca, Annalisa; Tutino, Maria

    2016-01-01

    Around 50% of the world's population, particularly in developing countries, uses biomass as one of the most common fuels. Biomass combustion releases a considerable amount of various incomplete combustion products, including particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs). The paper presents the results of Indoor Air Quality (IAQ) measurements in six houses equipped with wood burning stoves or fireplaces as heating systems. The houses were monitored for 48-h periods in order to collect PM10 samples and measure PAH concentrations. The average, the maximum and the lowest values of the 12-h PM10 concentration were 68.6 μg/m³, 350.7 μg/m³ and 16.8 μg/m³ respectively. The average benzo[a]pyrene 12-h concentration was 9.4 ng/m³, while the maximum and the minimum values were 24.0 ng/m³ and 1.5 ng/m³, respectively. Continuous monitoring of PM10, PAHs, Ultra Fine Particle (UFP) and Total Volatile Organic Compounds (TVOC) was performed in order to study the progress of pollution phenomena due to biomass burning, their trends and contributions to IAQ. The results show a great heterogeneity of impacts on IAQ in terms of magnitude and behavior of the considered pollutants' concentrations. This variability is determined by not only different combustion technologies or biomass quality, but overall by different ignition mode, feeding and flame management, which can also be different for the same house. Moreover, room dimensions and ventilation were significant factors for pollution dispersion. The increase of PM10, UFP and PAH concentrations, during lighting, was always detected and relevant. Continuous monitoring allowed singling out contributions of other domestic sources of considered pollutants such as cooking and cigarettes. Cooking contribution produced an impact on IAQ in same cases higher than that of the biomass heating system. PMID:26712773

  16. High relative air humidity and continuous light reduce stomata functionality by affecting the ABA regulation in rose leaves.

    PubMed

    Arve, Louise E; Terfa, Meseret T; Gislerød, Hans Ragnar; Olsen, Jorunn E; Torre, Sissel

    2013-02-01

    Plants developed under high (90%) relative air humidity (RH) have previously been shown to have large, malfunctioning stomata, which results in high water loss during desiccation and reduced dark induced closure. Stomatal movement is to a large extent regulated by abscisic acid (ABA). It has therefore been proposed that low ABA levels contribute to the development of malfunctioning stomata. In this study, we investigated the regulation of ABA content in rose leaves, through hormone analysis and β-glucosidase quantification. Compared with high RH, rose plants developed in moderate RH (60%) and 20 h photoperiod contained higher levels of ABA and β-glucosidase activity. Also, the amount of ABA increased during darkness simultaneously as the ABA-glucose ester (GE) levels decreased. In contrast, plants developed under high RH with 20 h photoperiod showed no increase in ABA levels during darkness, and had low β-glucosidase activity converting ABA-GE to ABA. Continuous lighting (24 h) resulted in low levels of β-glucosidase activity irrespective of RH, indicating that a dark period is essential to activate β-glucosidase. Our results provide new insight into the regulation of ABA under different humidities and photoperiods, and clearly show that β-glucosidase is a key enzyme regulating the ABA pool in rose plants. PMID:22812416

  17. Monitoring the impact of the indoor air quality on silver cultural heritage objects using passive and continuous corrosion rate assessments

    NASA Astrophysics Data System (ADS)

    `t Hart, Lucy; Storme, Patrick; Anaf, Willemien; Nuyts, Gert; Vanmeert, Frederik; Dorriné, Walter; Janssens, Koen; de Wael, Karolien; Schalm, Olivier

    2016-10-01

    There is a long tradition in evaluating industrial atmospheres by measuring the corrosion rate of exposed metal coupons. The heritage community also uses this method, but the interpretation of the corrosion rate often lacks clarity due to the low corrosivity in indoor museum environments. This investigation explores the possibilities and drawbacks of different silver corrosion rate assessments. The corrosion rate is determined by three approaches: (1) chemical characterization of metal coupons using analytical techniques such as electrochemical measurements, SEM-EDX, XRD, and µ-Raman spectroscopy, (2) continuous corrosion monitoring methods based on electrical resistivity loss of a corroding nm-sized metal wire and weight gain of a corroding silver coated quartz crystal, and (3) characterization of the visual degradation of the metal coupons. This study confirms that subtle differences in corrosivity between locations inside a museum can be determined on condition that the same corrosion rate assessment is used. However, the impact of the coupon orientation with respect to the prevailing direction of air circulation can be substantially larger than the impact of the coupon location.

  18. Long-term continuous measurement of near-road air pollution in Las Vegas: Seasonal variability in traffic emissions impact on local air quality

    EPA Science Inventory

    Excess air pollution along roadways is an issue of public health concern and motivated a long-term measurement effort established by the U.S. Environmental Protection Agency in Las Vegas, Nevada. Measurements of air pollutants – including black carbon (BC), carbon monoxide (CO),...

  19. Alpha7 nicotinic acetylcholine receptor activation ameliorates scopolamine-induced behavioural changes in a modified continuous Y-maze task in mice.

    PubMed

    Redrobe, John P; Nielsen, Elsebet Ø; Christensen, Jeppe K; Peters, Dan; Timmermann, Daniel B; Olsen, Gunnar M

    2009-01-01

    The alpha7 (alpha7) nicotinic acetylcholine receptor may represent a drug target for the treatment of disorders associated with working memory/attentional dysfunction. We investigated the effects of three distinct alpha7 nicotinic acetylcholine receptor agonists: 2-methyl-5-(6-phenyl-pyridazin-3-yl)-octahydro-pyrrolo[3,4-c]pyrrole (A-582941; 0.01-0.1 mg/kg), 4-bromophenyl 1,4-diazabicyclo(3.2.2) nonane-4-carboxylate (SSR180711; 0.3-3 mg/kg) and N-[(3R)-1-azabicyclo[2.2.2]oct-3-yl]-4-chlorobenzamide (PNU-282987; 1-10 mg/kg), on scopolamine-induced deficits in a modified Y-maze procedure. Mice were forced to choose one of two visually distinct arms, and were confined there for a 5 min exploration period before being allowed to explore both arms for a 2 min test session, immediately thereafter. The time spent in each arm, entries and total distance travelled were recorded using an automated system. Characterisation experiments showed that scopolamine-treated (1 mg/kg) mice spent less time exploring the unfamiliar arm, when compared with vehicle-treated animals. Combination experiments showed that all three alpha7 agonists ameliorated scopolamine-induced changes in unfamiliar arm exploration. In conclusion, the present data support the idea that alpha7 nicotinic acetylcholine receptors may represent an interesting target for the treatment of conditions associated with attentional/working memory dysfunction.

  20. Independent Evaluation of Air Filter Media from Chornobyl

    SciTech Connect

    MD Hoover; AF Fencl; GJ Vargo

    1999-12-21

    An independent evaluation was performed to assess the morphology, pressure drop characteristics, alpha spectroscopy characteristics, and collection efficiency of an air sampling filter media and two types of aerosol face masks provided from Chernobyl by Pacific Northwest National Laboratory. The evaluation included characterizing the filter morphology by scqg electron microscopy; measuring the filter pressure drop as a function of air flowrate; evaluating the spectroscopy characteristics of the filter for alpha-emitting radionuclides by sampling ambient radon progeny aerosols in an Eberline Alpha-6A alpha continuous air monitor; determining the particle collection efficiency of the filter media for 0.3 {micro}m aerodynamic diameter monodisperse particles at 1 and 2 cfm; and comparing the apparent construction, durability, and performance similarities of the filter media to other media commonly used for monitoring airborne alpha-emitting radionuclides.

  1. Simultaneous determination of 222Rn and 220Rn exhalation rates from building materials used in Central Italy with accumulation chambers and a continuous solid state alpha detector: influence of particle size, humidity and precursors concentration.

    PubMed

    Tuccimei, P; Moroni, M; Norcia, D

    2006-02-01

    A method to determine simultaneously the rates of 222Rn and 220Rn released from building materials quarried in Central Italy is presented. The method makes use of a continuous monitor equipped with a solid state alpha detector, in-line connected to a small accumulation chamber. The effects of chamber leakage and back diffusion on 222Rn free exhalation rate is evaluated. The influence of available exhalation surface, humidity content and precursors concentration on radon and thoron exhalation rates is investigated.

  2. Continuous distributions of ventilation-perfusion ratios in normal subjects breathing air and 100 per cent O2.

    PubMed

    Wagner, P D; Laravuso, R B; Uhl, R R; West, J B

    1974-07-01

    A new method has been developed for measuring virtually continuous distributions of ventilation-perfusion ratios (V(A)/Q) based on the steadystate elimination of six gases of different solubilities. The method is applied here to 12 normal subjects, aged 21-60. In nine, the distributions were compared breathing air and 100% oxygen, while in the remaining three, effects of changes in posture were examined. In four young semirecumbent subjects (ages 21-24) the distributions of blood flow and ventilation with respect to V(A)/Q were virtually log-normal with little dispersion (mean log standard deviations 0.43 and 0.35, respectively). The 95.5% range of both blood flow and ventilation was from V(A)/Q ratios of 0.3-2.1, and there was no intrapulmonary shunt (V(A)/Q of 0). On breathing oxygen, a shunt developed in three of these subjects, the mean value being 0.5% of the cardiac output. The five older subjects (ages 39-60) had broader distributions (mean log standard deviations, 0.76 and 0.44) containing areas with V(A)/Q ratios in the range 0.01-0.1 in three subjects. As for the young subjects, there was no shunt breathing air, but all five developed a shunt breathing oxygen (mean value 3.2%), and in one the value was 10.7%. Postural changes were generally those expected from the known effects of gravity, with more ventilation to high V(A)/Q areas when the subjects were erect than supine. Measurements of the shunt while breathing oxygen, the Bohr CO(2) dead space, and the alveolar-arterial oxygen difference were all consistent with the observed distributions. Since the method involves only a short infusion of dissolved inert gases, sampling of arterial blood and expired gas, and measurement of cardiac output and minute ventilation, we conclude that it is well suited to the investigation of pulmonary gas exchange in man.

  3. Estimation of high-level, rapidly-changing concentrations using moving-filter continuous particulate air monitors.

    PubMed

    Evans, William C

    2012-04-01

    A previously published mathematical model for the dynamic response of moving-filter continuous particulate air monitors has been enhanced to extend that model to include decay chains. During this work, it was observed that a quantitative relationship appeared to exist between the monitor count rate and the time-dependent particulate airborne radioactive material concentration if, and only if, the filter (tape) speed was much faster than the nominal 2.54 cm h(-1) (1 in h(-1)). The extended model demonstrated that operating moving-filter monitors at this nominal filter speed does not provide a quantitative measurement of a changing airborne particulate concentration of a fission product or other contaminant. By contrast, at faster filter speeds [e.g., 76.2 or 152.4 cm h(-1) (30 or 60 in h(-1))], numerical experimentation with this model showed that the count rate trace has essentially the same shape as the concentration profile. It was then found that a quantitative relationship applies, but only when the filter speed is sufficiently fast so that a Taylor series expansion of the monitor count rate can be reasonably well truncated at the first-order term. This mode of operation, which does not require any new monitor hardware, is capable of tracking rapidly changing concentrations. Since the fast filter speed also reduces the monitor's count rate, all else being equal, the approach will best be used for relatively high-level concentrations, such as may occur in abnormal or "accident" conditions. The count rate suppression may also be useful for reducing the detector saturation that can occur with higher levels of airborne particulate radioactivity in post-accident situations.

  4. 42 CFR 84.162 - Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air respirators; test requirements. 84.162 Section 84.162 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES...

  5. 42 CFR 84.162 - Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air respirators; test requirements. 84.162 Section 84.162 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES...

  6. 42 CFR 84.162 - Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air respirators; test requirements. 84.162 Section 84.162 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES...

  7. 42 CFR 84.162 - Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air respirators; test requirements. 84.162 Section 84.162 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES...

  8. 42 CFR 84.162 - Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air respirators; test requirements. 84.162 Section 84.162 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES...

  9. Event counting alpha detector

    DOEpatents

    Bolton, R.D.; MacArthur, D.W.

    1996-08-27

    An electrostatic detector is disclosed for atmospheric radon or other weak sources of alpha radiation. In one embodiment, nested enclosures are insulated from one another, open at the top, and have a high voltage pin inside and insulated from the inside enclosure. An electric field is produced between the pin and the inside enclosure. Air ions produced by collision with alpha particles inside the decay volume defined by the inside enclosure are attracted to the pin and the inner enclosure. With low alpha concentrations, individual alpha events can be measured to indicate the presence of radon or other alpha radiation. In another embodiment, an electrical field is produced between parallel plates which are insulated from a single decay cavity enclosure. 6 figs.

  10. Event counting alpha detector

    DOEpatents

    Bolton, Richard D.; MacArthur, Duncan W.

    1996-01-01

    An electrostatic detector for atmospheric radon or other weak sources of alpha radiation. In one embodiment, nested enclosures are insulated from one another, open at the top, and have a high voltage pin inside and insulated from the inside enclosure. An electric field is produced between the pin and the inside enclosure. Air ions produced by collision with alpha particles inside the decay volume defined by the inside enclosure are attracted to the pin and the inner enclosure. With low alpha concentrations, individual alpha events can be measured to indicate the presence of radon or other alpha radiation. In another embodiment, an electrical field is produced between parallel plates which are insulated from a single decay cavity enclosure.

  11. Evaluation of effect of continuous positive airway pressure during cardiopulmonary bypass on cardiac de-airing after open heart surgery in randomized clinical trial

    PubMed Central

    Mansour, Mojtaba; Massodnia, Nasim; Mirdehghan, Abolghasem; Bigdelian, Hamid; Massoumi, Gholamreza; Alavi, Zeinab Rafieipour

    2014-01-01

    Background: Cardiac and pulmonary veins de-airing are of the most important steps during open heart surgery. This study evaluates the effect of continuous positive airway pressure (CPAP) on air trapping in pulmonary veins and on quality of de-airing procedure. Materials and Methods: This randomized prospective double blind clinical trial conducted on 40 patients. In the control group: During cardiopulmonary bypass (CPB), the ventilator was turned off and adjustable pressure limit (APL) valve was placed in SPONT position. In CPAP group: During CPB, after turning the ventilator off, the flow of oxygen flow was maintained at the rate of 0.5 L/min and the APL valve was placed in MAN position on 20 mbar. During cardiopulmonary bypass (CPB) weaning, the patients were observed for air bubbles in left atrium by using transesophageal echocardiography. Results: The mean de-airing time after the start of mechanical ventilation in CPAP group (n = 20) was significantly lower than the control group (n = 20) (P = 0.0001). The mean time of the left atrium air bubbles occupation as mild (P = 0.004), moderate (P = 0.0001) and severe (P = 0.015) grading was significantly lower in CPAP group. Conclusions: By CPAP at 20 mbar during CPB in open heart surgery, de-airing process can be down in better quality and in significantly shorter time. PMID:24949307

  12. CONTINUED DEVELOPMENT AND TESTING OF A NEW THERMODYNAMIC AEROSOL MODULE FOR URBAN AND REGIONAL AIR QUALITY MODELS. (R824793)

    EPA Science Inventory

    A computationally efficient and rigorous thermodynamic model (ISORROPIA) that predicts the physical state and composition of inorganic atmospheric aerosol is presented. The advantages of this particular model render it suitable for incorporation into urban and regional air qualit...

  13. Using continuous measurements of near-surface atmospheric water vapor isotopes to document snow-air interactions

    NASA Astrophysics Data System (ADS)

    Steen-Larsen, Hans Christian; Masson-Delmotte, Valerie; Hirabayashi, Motohiro; Winkler, Renato; Satow, Kazuhide; Prie, Frederic; Bayou, Nicolas; Brun, Eric; Cuffey, Kurt; Dahl-Jensen, Dorthe; Dumont, Marie; Guillevic, Myriam; Kipfstuhl, Sepp; Landais, Amaelle; Popp, Trevor; Risi, Camille; Steffen, Konrad; Stenni, Barbara; Sveinbjornsdottir, Arny

    2014-05-01

    Water stable isotope data from Greenland ice cores provide key paleoclimatic information. However, post-depositional processes linked with snow metamorphism remain poorly documented. For this purpose, a monitoring of the isotopic composition δ18O and δD at several height levels (up to 13 meter) of near-surface water vapor, precipitation and snow in the first 0.5 cm from the surface has been conducted during three summers (2010-2012) at NEEM, NW Greenland. We observe a clear diurnal cycle in both the value and gradient of the isotopic composition of the water vapor above the snow surface. The diurnal amplitude in δD is found to be ~15‰. The diurnal isotopic composition follows the absolute humidity cycle. This indicates a large flux of vapor from the snow surface to the atmosphere during the daily warming and reverse flux during the daily cooling. The isotopic measurements of the flux of water vapor above the snow give new insights into the post depositional processes of the isotopic composition of the snow. During nine 1-5 days periods between precipitation events, our data demonstrate parallel changes of δ18O and d-excess in surface snow and near-surface vapor. The changes in δ18O of the vapor are similar or larger than those of the snow δ18O. It is estimated using the CROCUS snow model that 6 to 20% of the surface snow mass is exchanged with the atmosphere. In our data, the sign of surface snow isotopic changes is not related to the sign or magnitude of sublimation or deposition. Comparisons with atmospheric models show that day-to-day variations in near-surface vapor isotopic composition are driven by synoptic variations and changes in air mass trajectories and distillation histories. We suggest that, in-between precipitation events, changes in the surface snow isotopic composition are driven by these changes in near-surface vapor isotopic composition. This is consistent with an estimated 60% mass turnover of surface snow per day driven by snow

  14. Development of a local continuous sampling probe for the equivalence air-fuel ratio measurement. Application to spark ignition engine

    NASA Astrophysics Data System (ADS)

    Guibert, P.; Dicocco, E.

    This paper is a contribution to the development of an original technique for measuring the in-cylinder equivalence air-fuel ratio. The main objective was to construct an instrument able to furnish instantaneous values of hydrocarbon concentration for many consecutive cycles at a definite location, especially at the spark plug location. The probe is based on a hot-wire-like apparatus, but involves catalytic oxidation on the wire surface in order to be sensitive to the hydrocarbon concentration. In this paper, we present the different steps needed to develop and validate the probe. The first step focuses on the geometric configuration to simplify as much as possible the mass transfer phenomena on the wire. The second step is a parametric study to evaluate the sensitivity, confidence and lifetime of the wire. By physical analysis, we propose a relationship between the electrical signal and the air-fuel equivalence ratio of the sampled gases. The third step is the application of the probe to in-cylinder motored engine measurements, which confirms the ability of the technique to characterise, quantitatively, the homogeneity of the air-fuel mixture, especially during the compression stroke. This work points out that the global sensitivity is estimated at 4V per unit of equivalence air-fuel ratio and the response time is estimated at about 400μs. The equivalence air-fuel ratio range is from pure air to 1.2. Experiments show that it is necessary to calibrate the system before use because of the existence of multiple catalysis states. The probe presents advantages associated with its simplicity, its low cost and its direct engine application without any modifications.

  15. Application of continuous seismic-reflection techniques to delineate paleochannels beneath the Neuse River at US Marine Corps Air Station, Cherry Point, North Carolina

    USGS Publications Warehouse

    Cardinell, Alex P.

    1999-01-01

    A continuous seismic-reflection profiling survey was conducted by the U.S. Geological Survey on the Neuse River near the Cherry Point Marine Corps Air Station during July 7-24, 1998. Approximately 52 miles of profiling data were collected during the survey from areas northwest of the Air Station to Flanner Beach and southeast to Cherry Point. Positioning of the seismic lines was done by using an integrated navigational system. Data from the survey were used to define and delineate paleochannel alignments under the Neuse River near the Air Station. These data also were correlated with existing surface and borehole geophysical data, including vertical seismic-profiling velocity data collected in 1995. Sediments believed to be Quaternary in age were identified at varying depths on the seismic sections as undifferentiated reflectors and lack the lateral continuity of underlying reflectors believed to represent older sediments of Tertiary age. The sediments of possible Quaternary age thicken to the southeast. Paleochannels of Quaternary age and varying depths were identified beneath the Neuse River estuary. These paleochannels range in width from 870 feet to about 6,900 feet. Two zones of buried paleochannels were identified in the continuous seismic-reflection profiling data. The eastern paleochannel zone includes two large superimposed channel features identified during this study and in re-interpreted 1995 land seismic-reflection data. The second paleochannel zone, located west of the first paleochannel zone, contains several small paleochannels near the central and south shore of the Neuse River estuary between Slocum Creek and Flanner Beach. This second zone of channel features may be continuous with those mapped by the U.S. Geological Survey in 1995 using land seismic-reflection data on the southern end of the Air Station. Most of the channels were mapped at the Quaternary-Tertiary sediment boundary. These channels appear to have been cut into the older sediments

  16. Experimental study of heat transfer enhancement in solar air heater with different angle of attack of V-down continuous ribs

    NASA Astrophysics Data System (ADS)

    Istanto, Tri; Danardono, Dominicus; Yaningsih, Indri; Wijayanta, Agung Tri

    2016-06-01

    In this paper, an experimental study on the effect of angle attack in V-down continuous ribs on heat transfer and friction factor in an artificially roughened air heater duct is presented. The electric heater with a constant heat flux as a simulation of the indoor testing solar air heater is used to heat the roughened part of rectangular duct while other parts were insulated. The system and operating conditions were used to decide the range of parameters for the study. The ratio of the width to height of the duct (W/H) was 12, the relative roughness pitch (p/e) was 10, the relative roughness height (e/Dh) was 0.033 and the angle of attack of flow (α) was 30-80°. The air flow rate corresponded to Reynolds number between 3500 -10,000. The result of heat transfer and friction factor had been compared to those for smooth duct under similar flow and thermal boundary condition. The thermo-hydraulic performance also had been considered. As a result, the maximum enhancement of Nusselt number (Nu) and friction factor(f) were 2.34 and 2.45 times, respectively. For each variation of angle attack of flow, the thermo-hydraulic performance has been compared and the result shows that a V-down continuous rib with the angle of attack of flow as 60° gave the best thermo-hydraulic performance.

  17. A comparative study of dried apple using hot air, intermittent and continuous microwave: evaluation of kinetic parameters and physicochemical quality attributes.

    PubMed

    Aghilinategh, Nahid; Rafiee, Shahin; Gholikhani, Abolfazl; Hosseinpur, Soleiman; Omid, Mahmoud; Mohtasebi, Seyed S; Maleki, Neda

    2015-11-01

    In the study, the effectiveness of intermittent (IMWD) and continuous (CMWD) microwave drying and hot air drying (HAD) treatments on apple slices were compared in terms of drying kinetics (moisture diffusivity and activation energy) and critical physicochemical quality attributes (color change, rehydration ratio, bulk density, and total phenol content (TPC) of the final dried product. The temperature, microwave power, air velocity, and pulse ratio (PR) applied in the experiments were 40-80°C, 200-600 W, 0.5-2 m/s, and 2-6, respectively. Results showed that IMWD and CMWD more effective than HAD in kinetic parameters and physicochemical quality attributes. Also, results indicated CMWD had the lowest and highest drying time and effective diffusivity. The exponential model for estimating IMWD activation energy, considering absolute power (1/P) and pulse ratio were also represented. The color change in apple slices dried by HAD showed the highest change. PMID:26788293

  18. Continuous scanning of the mobility and size distribution of charged clusters and nanometer particles in atmospheric air and the Balanced Scanning Mobility Analyzer BSMA

    NASA Astrophysics Data System (ADS)

    Tammet, H.

    2006-12-01

    Measuring of charged nanometer particles in atmospheric air is a routine task in research on atmospheric electricity, where these particles are called the atmospheric ions. An aspiration condenser is the most popular instrument for measuring atmospheric ions. Continuous scanning of a mobility distribution is possible when the aspiration condenser is connected as an arm of a balanced bridge. Transfer function of an aspiration condenser is calculated according to the measurements of geometric dimensions, air flow rate, driving voltage, and electric current. The most complicated phase of the calibration is the estimation of the inlet loss of ions due to the Brownian deposition. The available models of ion deposition on the protective inlet screen and the inlet control electrofilter have the uncertainty of about 20%. To keep the uncertainty of measurements low the adsorption should not exceed a few tens of percent. The online conversion of the mobility distribution to the size distribution and a correct reduction of inlet losses are possible when air temperature and pressure are measured simultaneously with the mobility distribution. Two instruments called the Balanced Scanning Mobility Analyzers (BSMA) were manufactured and tested in routine atmospheric measurements. The concentration of atmospheric ions of the size of about a few nanometers is very low and a high air flow rate is required to collect enough of ion current. The air flow of 52 l/s exceeds the air flow in usual aerosol instruments by 2-3 orders of magnitude. The high flow rate reduces the time of ion passage to 60 ms and the heating of air in an analyzer to 0.2 K, which suppresses a possible transformation of ions inside the instrument. The mobility range of the BSMA of 0.032-3.2 cm 2 V - 1 s - 1 is logarithmically uniformly divided into 16 fractions. The size distribution is presented by 12 fractions in the diameter range of 0.4-7.5 nm. The measurement noise of a fraction concentration is typically

  19. Self-tempering of stepped shafts in water-air hardening by a continuous step-by-step method

    SciTech Connect

    Kunmashov, M.G.

    1983-01-01

    One of the advantages of water-air hardening is the possibility of conducting controlled self-tempering, which in surface induction hardening provides hardening without tempering in a furnace andexclamationthe creation of the optimum conditions for heat treatment in a single production line with full automation of the process. In addition, there are no hardening craccs on the treated parts. Investigation of the influence of the quenching and self-tempering times on the surface hardness was made on shaft model samples of 45 steel. The results of the inwestigations made show that a self-tempering time in the range from 10 to 60 seconds has little influence on the change in surface layer hardness. To obtain equal hardness in self-tempering (HRC 57-58), it is necessary to use higher temperatures than in furnace tempering. For 45 steel this difference is 75-85/sup 0/C with a tempering temperature up to 300/sup 0/C and 100-250/sup 0/C at higher temperatures. A comparison of the self-tempering and furnace tempering temperatures after hardening with a water-air mixture providing equal hardnesses of 45 steel are shown.

  20. Wide continuously tunable 1.55μm vertical air-cavity wavelength selective elements for filters and VCSELs using micromachined actuation (Invited Paper)

    NASA Astrophysics Data System (ADS)

    Hillmer, H.; Tarraf, A.; Riemenschneider, F.; Irmer, S.; Halbritter, H.; Daleiden, J.; Romer, F.; Prott, C.; Ataro, E.; Hasse, A.; Strassner, M.; Hansmann, S.; Meissner, P.

    2005-06-01

    Tailored scaling allows the effectiveness of physical effects and mechanical stability to be enhanced. This is shown for micromachined 1.55μm vertical-resonator-based filters and VCSELs, capable of wide, continuous, and kink-free tuning by a single control parameter. Tuning is achieved by mechanically actuating one or several membranes in a vertical air-gap resonator including two highly reflective DBR mirrors. Electrostatically actuatable single-chip filters including InP/air-gap DBR's (3.5 periods) reveal a continuous tuning up to 14% of the absolute wavelength. Varying a reverse voltage (U=0 .. -3.2V) between the membranes (almost flat in the unactuated condition) a tuning range up to 142nm was obtained. Varying a reverse voltage (U=0 .. -28V) between the membranes (strained and curved in the unactuated condition) a tuning range up to 221nm was obtained. Optically pumped and continuously tunable 1.55μm VCSELs show 26nm spectral tuning range, 400μW maximum output power, and 57dBm SMSR. This two-chip VCSEL has a movable top mirror membrane, which is precisely designed to obtain a specific air-gap length and a tailored radius of curvature in order to efficiently support the fundamental optical mode of the plane-concave resonator. The curved top mirror DBR membrane consists of periodically alternating differently stressed silicon nitride and silicon dioxide multilayers. The lower InP-based part consists of the InP/GaInAsP bottom DBR and the GaInAsP active region.

  1. Assessment of 17{alpha}-ethinylestradiol effects and underlying mechanisms in a continuous, multigeneration exposure of the Chinese rare minnow (Gobiocypris rarus)

    SciTech Connect

    Zha Jinmiao; Sun Liwei; Zhou Yiqi; Spear, Philip A.; Ma, Mei; Wang Zijian

    2008-02-01

    17{alpha}-Ethinylestradiol (EE{sub 2}) is a synthetic estrogen used primarily in birth control pills and in hormone replacement therapy. Owing to its occurrence in surface waters at concentrations frequently greater than 1 ng/l and its projected future use, EE{sub 2} is expected to pose a significant risk to aquatic organisms. This study was conducted to obtain long-term exposure data necessary for the establishment of water quality criteria and to investigate mechanisms associated with toxic effects. In a multigeneration experiment, Chinese rare minnows (Gobiocypris rarus) were constantly exposed to environmentally relevant concentrations of the synthetic estrogen EE{sub 2}. Mortality, deformities, reproductive parameters, plasma vitellogenin and histopathology were assessed. The results showed that, in the F{sub 0} generation, all endpoints were significantly affected at concentrations higher than 0.2 ng/l EE{sub 2}. No F{sub 1} phenotypic males developed to maturity at 0.2 ng/l and, when adult females of this exposure group were crossed with unexposed males, no F{sub 2} fertile eggs were produced. Kidney histopathology and ultrastructure suggest anomalies possibly associated with increased vitellogenin accumulation. We concluded that the reproduction of the F{sub 1} minnows was completely inhibited at the lowest concentration tested, 0.2 ng/l EE{sub 2}, a concentration frequently detected in surface waters. Growth effects may be related to increased energy requirements including the energy used in VTG synthesis. Reproductive effects are presumably associated with male feminization and the occurrence of testis-ova in males; however, ovarian degeneration observed in females may also have contributed to reproductive failure.

  2. Influence of the continuous and dispersed phases on the symmetry of a gas turbine air-blast atomizer

    NASA Technical Reports Server (NTRS)

    Mcdonell, V. G.; Samuelsen, G. S.

    1990-01-01

    Current trends in liquid-fueled practical combustion systems are leaving less tolerance for fuel injection deficiencies such as poor spray field symmetry. The present paper evaluates the symmetry of the flowfield produced by a practical airblast atomizer. Specifically, the influence of both the continuous phase and dispersed phase on the spray field symmetry is assessed. In the present case, asymmetry in volume flux is associated principally with disparities in the injection of the dispersed phase, which is manifested by a maldistribution of larger drops. Asymmetries observed in the continuous phase without the dispersed phase are reduced in magnitude by the presence of the dispersed phase, but still contribute to asymmetry in radial spread of the dispersed phase.

  3. Continuous low-dose infusion of tumor necrosis factor alpha in adipose tissue elevates adipose tissue interleukin 10 abundance and fails to alter metabolism in lactating dairy cows.

    PubMed

    Martel, Cynthia A; Mamedova, Laman K; Minton, J Ernest; Jones, Meredyth L; Carroll, Jeff A; Bradford, Barry J

    2014-01-01

    Repeated bolus doses of tumor necrosis factor-α (TNFα) alters systemic metabolism in lactating cows, but whether chronic release of inflammatory cytokines from adipose tissue has similar effects is unclear. Late-lactation Holstein cows (n=9-10/treatment) were used to evaluate the effects of continuous adipose tissue TNFα administration on glucose and fatty acid (FA) metabolism. Cows were blocked by feed intake and milk yield and randomly assigned within block to control or TNFα treatments. Treatments (4mL of saline or 14µg/kg of TNFα in 4mL of saline) were infused continuously over 7d via 2 osmotic pumps implanted in a subcutaneous adipose depot. Plasma, milk samples, milk yield, and feed intake data were collected daily, and plasma glucose turnover rate was measured on d 7. At the end of d 7, pumps were removed and liver and contralateral tail-head adipose biopsies were collected. Results were modeled with the fixed effect of treatment and the random effect of block. Treatment with TNFα increased plasma concentrations of the acute phase protein haptoglobin, but did not alter plasma TNFα, IL-4, IL-6, or IFN-γ concentrations, feed intake, or rectal temperature. Milk yield and composition were unchanged, and treatments did not alter the proportion of short- versus long-chain FA in milk on d 7. Treatments did not alter plasma free FA concentration, liver triglyceride content, or plasma glucose turnover rate. Surprisingly, TNFα infusion tended to decrease liver TNFα and IL-1 receptor 1 mRNA abundance and significantly increased adipose tissue IL-10 protein concentration. Continuous infusion of TNFα did not induce the metabolic responses previously observed following bolus doses delivered at the same rate per day. Metabolic homeostasis may have been protected by an adaptive anti-inflammatory response to control systemic inflammation.

  4. The "Lung": a software-controlled air accumulator for quasi-continuous multi-point measurement of agricultural greenhouse gases

    NASA Astrophysics Data System (ADS)

    Martin, R. J.; Bromley, A. M.; Harvey, M. J.; Moss, R. C.; Pattey, E.; Dow, D.

    2011-10-01

    We describe the design and testing of a flexible bag ("Lung") accumulator attached to a gas chromatographic (GC) analyzer capable of measuring surface-atmosphere greenhouse gas exchange fluxes in a wide range of environmental/agricultural settings. In the design presented here, the Lung can collect up to three gas samples concurrently, each accumulated into a Tedlar bag over a period of 20 min or longer. Toggling collection between 2 sets of 3 bags enables quasi-continuous collection with sequential analysis and discarding of sample residues. The Lung thus provides a flexible "front end" collection system for interfacing to a GC or alternative analyzer and has been used in 2 main types of application. Firstly, it has been applied to micrometeorological assessment of paddock-scale N2O fluxes, discussed here. Secondly, it has been used for the automation of concurrent emission assessment from three sheep housed in metabolic crates with gas tracer addition and sampling multiplexed to a single GC. The Lung allows the same GC equipment used in laboratory discrete sample analysis to be deployed for continuous field measurement. Continuity of measurement enables spatially-averaged N2O fluxes in particular to be determined with greater accuracy, given the highly heterogeneous and episodic nature of N2O emissions. We present a detailed evaluation of the micrometeorological flux estimation alongside an independent tuneable diode laser system, reporting excellent agreement between flux estimates based on downwind vertical concentration differences. Whilst the current design is based around triplet bag sets, the basic design could be scaled up to a larger number of inlets or bags and less frequent analysis (longer accumulation times) where a greater number of sampling points are required.

  5. Numerical study of a continuous optical discharge in atmospheric air in the framework of a one-dimensional model

    NASA Astrophysics Data System (ADS)

    Raizer, Iu. P.; Surzhikov, S. T.

    1985-07-01

    A quasi-one-dimensional model of the continuous discharge of a CW CO2 laser is constructed. The laser beam parameters used in the model include: the thermal radiation coefficient; and the motion of the CO2 gas along the optical axis. The parameters of the optical discharge are estimated numerically and the results are compared with the available experimental data. The estimated temperature distribution of a 6-kW optical discharge is given in a graph, and the location and size of the high-temperature region of the discharge are shown.

  6. Water- and Air-Quality Monitoring of the Sweetwater Reservoir Watershed, San Diego County, California-Phase One Results, Continued, 1999-2001

    USGS Publications Warehouse

    Mendez, Gregory O.; Foreman, William T.; Sidhu, Jagdeep S.; Majewski, Michael S.

    2007-01-01

    In 1998, the U.S. Geological Survey, in cooperation with the Sweetwater Authority, began a study to assess the overall health of the Sweetwater watershed with respect to chemical contamination. The study included regular sampling of air and water at Sweetwater Reservoir for chemical contaminants, including volatile organic compounds, polycyclic aromatic hydrocarbons, pesticides, and major and trace elements. Background water samples were collected at Loveland Reservoir for volatile organic compounds and pesticides. The purpose of this study was to monitor changes in contaminant composition and concentration in the air and water resulting from the construction and operation of State Route 125 near Sweetwater Reservoir. To accomplish this, the study was divided into two phases. Phase One sampling was designed to establish baseline conditions for target compounds in terms of detection frequency and concentration in air and water. Phase Two sampling is planned to continue at the established monitoring sites during and after construction of State Route 125 to assess the chemical impact this roadway alignment project may have on the water quality in the reservoir. In addition to the ongoing data collection, several special studies were initiated to assess the occurrence of specific chemicals of concern, such as low-use pesticides, trace metals, and wastewater compounds. This report describes the study design, and the sampling and analytical methods, and presents the results for the second and third years of the study (October 1999 to September 2001). Data collected during the first year of sampling (October 1998 to September 1999) were published in 2002.

  7. Ultrawide continuously tunable 1.55-μm vertical-air-cavity filters and VCSELs based on micromachined electrostatic actuation

    NASA Astrophysics Data System (ADS)

    Hillmer, Hartmut; Daleiden, Juergen; Prott, Cornelia; Roemer, Friedhard; Tarraf, Amer; Irmer, Soeren; Rangelov, Ventzeslav; Schueler, S.; Strassner, Martin

    2002-06-01

    We study 1.55micrometers filter and VCSEL devices capable of wide and continuous tuning based on a single control parameter. Ultra-high reflective DBR mirrors are realized with a low number of DBR periods using high refractive index contrast: (I) (Delta) n=2.17 for InP/airgap DBR's (3.5 periods) and (II) (Delta) n=0.5 for Si3N4/SiO2 DBR's (12 periods) with a polymer sacrificial layer to implement the air-cavity. Corresponding fabrication technologies are presented in detail. In both cases spectral tuning (>100nm, theoretically) is obtained by micomachined actuation of the included air-cavity. Large stopband widths and very large tuning efficiencies are obtained by model calculations. For VCSEL's a trade-off between lasing efficiency and tuning efficiency is obtained. Experimental results show very good optical properties: high mirror reflectance and clear single-line filter transmission. The first tunable dielectric filter based on polymer sacrificial layers is presented: (Delta) (lambda) /(Delta) U= -7nm/V at 1mA. The potential of the airgap concept: the filter transmission or the laser emission wavelength can be continuously tuned over more than 100nm, thus, the whole spectral gain profile can be addressed by a single control parameter.

  8. Alpha Thalassemia

    MedlinePlus

    ... an apparently normal individual has a child with hemoglobin H disease or alpha thalassemia minor. It can ... gene on one chromosome 25% 25% 25% 25% hemoglobin H disease there is a 25% chance with ...

  9. Water- and Air-Quality Monitoring of Sweetwater Reservoir Watershed, San Diego County, California - Phase One Results Continued, 2001-2003

    USGS Publications Warehouse

    Mendez, Gregory O.; Foreman, William T.; Morita, Andrew; Majewski, Michael S.

    2008-01-01

    In 1998, the U.S. Geological Survey, in cooperation with the Sweetwater Authority, began a study to monitor water, air, and sediment at the Sweetwater and Loveland Reservoirs in San Diego County, California. The study includes regular sampling of water and air at Sweetwater Reservoir for chemical constituents, including volatile organic compounds (VOC), polynuclear aromatic hydrocarbons (PAH), pesticides, and major and trace elements. The purpose of this study is to monitor changes in contaminant composition and concentration during the construction and operation of State Route 125. To accomplish this, the study was divided into two phases. Phase One sampling (water years 1998-2004) determined baseline conditions for the detection frequency and the concentrations of target compounds in air and water. Phase Two sampling (starting water year 2005) continues at selected monitoring sites during and after construction of State Route 125 to assess the chemical impact this roadway alignment may have on water quality in the reservoir. Water samples were collected for VOCs and pesticides at Loveland Reservoir during Phase One and will be collected during Phase Two for comparison purposes. Air samples collected to monitor changes in VOCs, PAHs, and pesticides were analyzed by adapting methods used to analyze water samples. Bed-sediment samples have been and will be collected three times during the study; at the beginning of Phase One, at the start of Phase Two, and near the end of the study. In addition to the ongoing data collection, several special studies were initiated to assess the occurrence of specific chemicals of concern, such as trace metals, anthropogenic indicator compounds, and pharmaceuticals. This report describes the study design, and the sampling and analytical methods, and presents data from water and air samples collected during the fourth and fifth years of Phase One of the study (October 2001 to September 2003). Data collected during the first three

  10. Operability of the Ventilation Continuous Air Monitor (CAM) Interlock Analysis of Proposed Upgrade to the 241AW Farm Primary Exhauster CAM System

    SciTech Connect

    GUSTAVSON, R.D.

    2002-06-19

    The Tank Farms Final Safety Analysis (FSAR) assumes that a ventilation stack Continuous Air Monitor (CAM) interlock system detects high radiation in the exhaust stream and shuts off the associated ventilation system within 10 minutes of a High-Efficiency Particulate Air (HEPA) filter system failure (CHG, 2002). Previous analysis of the as-built CAM system on the AW Farm Primary Exhauster (stack 296-A-27) showed that this system potentially required significantly longer than 10 minutes to detect a HEPA filter failure and initiate shutdown of the ventilation system (Short, 2002). The purpose of this report is to determine the CAM interlock system response time for a proposed upgrade of the 296-A-27 CAM system. The approach to be used in this analysis is essentially the same as used in RPP-10799, Rev. 0 (Short, 2002), which is to conservatively estimate the time required by the proposed upgraded CAM sampling/monitoring system to detect a FSAR-defined HEPA filter failure and automatically shutdown the exhaust fan. For the HEPA filter failure over-temperature accident scenario in the FSAR, the upgraded CAM system on the AW Farm Primary Exhauster will require significantly less than 10 minutes to detect a HEPA filter failure, actuate the CAM Interlock, and shutdown the exhauster fan. Therefore, the analyzed system is adequate to meet the operability requirements specified in the FSAR and the Tank Farms Technical Safety Requirements (CHG, 2001; CHG, 2002).

  11. Corn leaf nitrate reductase - A nontoxic alternative to cadmium for photometric nitrate determinations in water samples by air-segmented continuous-flow analysis

    USGS Publications Warehouse

    Patton, C.J.; Fischer, A.E.; Campbell, W.H.; Campbell, E.R.

    2002-01-01

    Development, characterization, and operational details of an enzymatic, air-segmented continuous-flow analytical method for colorimetric determination of nitrate + nitrite in natural-water samples is described. This method is similar to U.S. Environmental Protection Agency method 353.2 and U.S. Geological Survey method 1-2545-90 except that nitrate is reduced to nitrite by soluble nitrate reductase (NaR, EC 1.6.6.1) purified from corn leaves rather than a packed-bed cadmium reactor. A three-channel, air-segmented continuous-flow analyzer-configured for simultaneous determination of nitrite (0.020-1.000 mg-N/L) and nitrate + nitrite (0.05-5.00 mg-N/L) by the nitrate reductase and cadmium reduction methods-was used to characterize analytical performance of the enzymatic reduction method. At a sampling rate of 90 h-1, sample interaction was less than 1% for all three methods. Method detection limits were 0.001 mg of NO2- -N/L for nitrite, 0.003 mg of NO3-+ NO2- -N/L for nitrate + nitrite by the cadmium-reduction method, and 0.006 mg of NO3- + NO2- -N/L for nitrate + nitrite by the enzymatic-reduction method. Reduction of nitrate to nitrite by both methods was greater than 95% complete over the entire calibration range. The difference between the means of nitrate + nitrite concentrations in 124 natural-water samples determined simultaneously by the two methods was not significantly different from zero at the p = 0.05 level.

  12. Comparison of MODIS-derived land surface temperatures with near-surface soil and air temperature measurements in continuous permafrost terrain

    NASA Astrophysics Data System (ADS)

    Hachem, S.; Duguay, C. R.; Allard, M.

    2011-05-01

    In Arctic and sub-Arctic regions, meteorological stations are scattered and poorly distributed geographically; they are mostly located along coastal areas and are often unreachable by road. Given that high-latitude regions are the ones most significantly affected by recent climate warming, there is a need to supplement existing meteorological station networks with spatially continuous measurements such as those obtained by spaceborne platforms. In particular, land surface (skin) temperature (LST) retrieved from satellite sensors offer the opportunity to utilize remote sensing technology to obtain a consistent coverage of a key parameter for climate, permafrost, and hydrological research. The Moderate Resolution Imaging Spectroradiometer (MODIS) sensor aboard the Terra and Aqua satellite platforms offers the potential to provide spatial estimates of near-surface temperature values. In this study, LST values from MODIS were compared to ground-based near-surface air and soil temperature measurements obtained at herbaceous and shrub tundra sites located in the continuous permafrost zone of northern Québec, Canada, and the North Slope of Alaska, USA. LST values were found to be better correlated with near-surface air temperature (1-2 m above the ground) than with soil temperature (3-5 cm below the ground) measurements. A comparison between mean daily air temperature from ground-based station measurements and mean daily MODIS LST, calculated from daytime and nighttime temperature values of both Terra and Aqua acquisitions, for all sites and all seasons pooled together reveals a high correlation between the two sets of measurements (R>0.93 and mean difference of -1.86 °C). Mean differences ranged between -0.51 °C and -5.13 °C due to the influence of surface heterogeneity within the MODIS 1 km2 grid cells at some sites. Overall, it is concluded that MODIS offers a great potential for monitoring surface temperature changes in high-latitude tundra regions and provides a

  13. Alpha-1 Antitrypsin Deficiency

    MedlinePlus

    ... Liver Disease Information > Alpha-1 Antitrypsin Deficiency Alpha-1 Antitrypsin Deficiency Explore this section to learn more about alpha-1 antitrypsin deficiency, including a description of the disorder ...

  14. An assessment of the performance of the Monitor for AeRosols and GAses in ambient air (MARGA): a semi-continuous method for soluble compounds

    NASA Astrophysics Data System (ADS)

    Rumsey, I. C.; Cowen, K. A.; Walker, J. T.; Kelly, T. J.; Hanft, E. A.; Mishoe, K.; Rogers, C.; Proost, R.; Beachley, G. M.; Lear, G.; Frelink, T.; Otjes, R. P.

    2013-09-01

    Ambient air monitoring as part of the US Environmental Protection Agency's (US EPA's) Clean Air Status and Trends Network (CASTNet) currently uses filter packs to measure weekly integrated concentrations. The US EPA is interested in supplementing CASTNet with semi-continuous monitoring systems at select sites to characterize atmospheric chemistry and deposition of nitrogen and sulfur compounds at higher time resolution than the filter pack. The Monitor for AeRosols and GAses in ambient air (MARGA) measures water-soluble gases and aerosols at hourly temporal resolution. The performance of the MARGA was assessed under the US EPA Environmental Technology Verification (ETV) program. The assessment was conducted in Research Triangle Park, North Carolina from 8 September-8 October 2010 and focused on gaseous SO2, HNO3 and NH3 and aerosol SO4-, NO3- and NH4+. Precision of the MARGA was evaluated by calculating the median absolute relative percent difference (MARPD) between paired hourly results from duplicate MARGA units (MUs), with a performance goal of <25%. The accuracy of the MARGA was evaluated by calculating the median absolute relative percent difference (MARPD) for each MU relative to the average of the duplicate denuder/filter pack concentrations, with a performance goal of ≤40%. Accuracy was also evaluated by using linear regression, where MU concentrations were plotted against the average of the duplicate denuder/filter pack concentrations. From this, a linear least squares line of best fit was applied. The goal was for the slope of the line of best fit to be between 0.8 and 1.2. The MARGA performed well in comparison to the denuder/filter pack for SO2, SO42- and NH4+, with all three compounds passing the accuracy and precision goals by a significant margin. The performance of the MARGA in measuring NO3- could not be evaluated due to the different sampling efficiency of coarse NO3- by the MUs and the filter pack. Estimates of "fine" NO3- were calculated for

  15. An assessment of the performance of the Monitor for AeRosols and GAses in ambient air (MARGA): a semi-continuous method for soluble compounds

    NASA Astrophysics Data System (ADS)

    Rumsey, I. C.; Cowen, K. A.; Walker, J. T.; Kelly, T. J.; Hanft, E. A.; Mishoe, K.; Rogers, C.; Proost, R.; Beachley, G. M.; Lear, G.; Frelink, T.; Otjes, R. P.

    2014-06-01

    Ambient air monitoring as part of the US Environmental Protection Agency's (US EPA's) Clean Air Status and Trends Network (CASTNet) currently uses filter packs to measure weekly integrated concentrations. The US EPA is interested in supplementing CASTNet with semi-continuous monitoring systems at select sites to characterize atmospheric chemistry and deposition of nitrogen and sulfur compounds at higher time resolution than the filter pack. The Monitor for AeRosols and GAses in ambient air (MARGA) measures water-soluble gases and aerosols at an hourly temporal resolution. The performance of the MARGA was assessed under the US EPA Environmental Technology Verification (ETV) program. The assessment was conducted in Research Triangle Park, North Carolina, from 8 September to 8 October 2010 and focused on gaseous SO2, HNO3, and NH3 and aerosol SO42-, NO3-, and NH4+. Precision of the MARGA was evaluated by calculating the median absolute relative percent difference (MARPD) between paired hourly results from duplicate MARGA units (MUs), with a performance goal of ≤ 25%. The accuracy of the MARGA was evaluated by calculating the MARPD for each MU relative to the average of the duplicate denuder/filter pack concentrations, with a performance goal of ≤ 40%. Accuracy was also evaluated by using linear regression, where MU concentrations were plotted against the average of the duplicate denuder/filter pack concentrations. From this, a linear least squares line of best fit was applied. The goal was for the slope of the line of best fit to be between 0.8 and 1.2. The MARGA performed well in comparison to the denuder/filter pack for SO2, SO42-, and NH4+, with all three compounds passing the accuracy and precision goals by a significant margin. The performance of the MARGA in measuring NO3- could not be evaluated due to the different sampling efficiency of coarse NO3- by the MUs and the filter pack. Estimates of "fine" NO3- were calculated for the MUs and the filter pack

  16. Use of sulfur hexafluoride airflow studies to determine the appropriate number and placement of air monitors in an alpha inhalation exposure laboratory

    SciTech Connect

    Newton, G.J.; Hoover, M.D.

    1997-12-01

    Determination of the number and placement of air monitors in the workplace is subjective and is generally one of the more difficult tasks in radiation protection. General guidance for determining this task is provided by technical reports such as Mishima et al. and Hickey et al. These two documents and other guidelines suggest that some insight into sampler placement can be obtained by conducting airflow studies involving dilution and clearance of sulfur hexafluoride (SF{sub 6}). Objectives of the study were to document a method for conducting SF{sub 6} dispersion studies and to confirm the number and placement of air monitors within a typical Inhalation Toxicology Research Institute (ITRI) inhalation exposure laboratory.

  17. The role of formation of continues thermally grown oxide layer on the nanostructured NiCrAlY bond coat during thermal exposure in air

    NASA Astrophysics Data System (ADS)

    Daroonparvar, Mohammadreza; Hussain, Mohammad Sakhawat; Yajid, Muhammad Azizi Mat

    2012-11-01

    In recent years, the life expectancy of thermal barrier coatings is expected to be improved by applying the nanostructured NiCrAlY bond coat. The present paper reviews the main technique used in the synthesis of nano-crystalline NiCrAlY powders using a planetary ball mill and investigates the microstructural evolution of thermally grown oxide (TGO) layer on the conventional and nanostructured atmospheric plasma sprayed (APS) NiCrAlY coatings in thermal barrier coating (TBC) systems during oxidation. Microstructural characterization showed that the growth of Ni(Cr,Al)2O4 (as spinel) and NiO on the surface of Al2O3 layer (as pure TGO) in nano TBC system was much lower compared to that of normal TBC system during thermal exposure at 1150 °C. These two oxides play a detrimental role in causing crack nucleation and growth, reducing the life of the TBC in air. This microstructure optimization of TGO layer is primarily associated with the formation of a continuous, dense, uniform Al2O3 layer (at first 24 h of isothermal oxidation at 1000 °C) over the nanostructured NiCrAlY coating.

  18. Continued investigations in the NAAL low speed wind tunnel into the effects of the air breathing propulsion system on orbiter subsonic stability and control characteristics (OA62A)

    NASA Technical Reports Server (NTRS)

    Mennell, R.

    1974-01-01

    Experimental aerodynamic investigations were conducted on a stingmounted 0.0405-scale representation (model 43-0) of the 140A/B Space Shuttle Orbiter in a Low Speed Wind Tunnel. The NASA designation for this test was 0A62A. The primary test objective was to continue studies, initiated on tests 0A16 and 0A71A and 0A71C, in optimizing the air breathing propulsion system (ABPS) and investigating the aerodynamic effects of various nacelle number/location configurations on the orbiter stability and control characteristics. Orbiter stability and control characteristics, both with and without ABPS, were investigated at elevon deflections of 0, + or -5, + or -19, + or -5, and -20 deg; aileron deflections of 0 and 10 deg (about 0 deg elevon); and rudder deflections of 0, -7.5, and -15 deg. Aerodynamic force and moment data was measured in the body axis system by a 2.5-inch task type internal balance. The model was sting supported through the base region with a nominal angle of attack range of -4 to 30 deg. Yaw polars were recorded over the beta range of -10 to 10 deg at fixed angles of attack of 0, 5, 10, and 15 deg.

  19. Air Proportional Counter

    DOEpatents

    Simpson, Jr, J A

    1950-12-05

    A multiple wire counter utilizing air at atmospheric pressure as the ionizing medium and having a window of a nylon sheet of less than 0.5 mil thickness coated with graphite. The window is permeable to alpha particles so that the counter is well adapted to surveying sources of alpha radiation.

  20. PNNL OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual, Revision 0

    SciTech Connect

    Barnett, J. Matthew; Duchsherer, Cheryl J.; Sisk, Daniel R.; Carter, Gregory L.; Douglas, David D.; Carrell, Dorothy M.

    2006-01-25

    This Pacific Northwest National Laboratory (PNNL) OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual describes how to install and operate the software and hardware on a personal computer in conjunction with the EG&G Berthold LB150D continuous air monitor. Included are operational details for the software functions, how to read and use the drop-down menus, how to understand readings and calculations, and how to access the database tables.

  1. Technical aspects of the sigma factor alarm method in alpha CAMs

    SciTech Connect

    Justus, Alan Lawrence

    2009-01-01

    Some test must be applied to the low-level count data from alpha continuous air monitors (CAMs) to determine if the count is statistically significant (i.e., different from background). The test should also automatically account for different levels of background (i.e., ambient radon progeny concentrations). The method should, in other words, be as sensitive as possible, automatically desensitize when required, but in such a manner as to not exceed a previously-chosen acceptable false-alarm rate.

  2. Inter-alpha-trypsin inhibitor heavy chain 4: a novel biomarker for environmental exposure to particulate air pollution in patients with chronic obstructive pulmonary disease.

    PubMed

    Lee, Kang-Yun; Feng, Po-Hao; Ho, Shu-Chuan; Chuang, Kai-Jen; Chen, Tzu-Tao; Su, Chien-Ling; Liu, Wen-Te; Chuang, Hsiao-Chi

    2015-01-01

    Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease that is correlated with environmental stress. Particulate matter ≤10 μm (PM10) is considered to be a risk factor for COPD development; however, the effects of PM10 on the protein levels in COPD remain unclear. Fifty subjects with COPD and 15 healthy controls were recruited. Gene ontology analysis of differentially expressed proteins identified immune system process and binding as the most important biological process and molecular function, respectively, in the responses of PM10-exposed patients with COPD. Biomarkers for PM10 in COPD were identified and compared with the same in healthy controls and included proteoglycan 4 (PRG4), inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4), and apolipoprotein F (APOF). PRG4 and ITIH4 were associated with a past 3-year PM10 exposure level. The receiver operating characteristic curve analysis showed that ITIH4 is a sensitive and specific biomarker for PM10 exposure (area under the curve [AUC] =0.690, P=0.015) compared with PRG4 (AUC =0.636, P=0.083), APOF (AUC =0.523, P=0.766), 8-isoprostane (AUC =0.563, P=0.405), and C-reactive protein (CRP; AUC =0.634, P=0.086). ITIH4 levels were correlated with CRP (r=0.353, P=0.005), suggesting that ITIH4 may be involved in an inflammatory mechanism. In summary, serum ITIH4 may be a PM10-specific biomarker in COPD and may be related to inflammation.

  3. Inter-alpha-trypsin inhibitor heavy chain 4: a novel biomarker for environmental exposure to particulate air pollution in patients with chronic obstructive pulmonary disease

    PubMed Central

    Lee, Kang-Yun; Feng, Po-Hao; Ho, Shu-Chuan; Chuang, Kai-Jen; Chen, Tzu-Tao; Su, Chien-Ling; Liu, Wen-Te; Chuang, Hsiao-Chi

    2015-01-01

    Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease that is correlated with environmental stress. Particulate matter ≤10 μm (PM10) is considered to be a risk factor for COPD development; however, the effects of PM10 on the protein levels in COPD remain unclear. Fifty subjects with COPD and 15 healthy controls were recruited. Gene ontology analysis of differentially expressed proteins identified immune system process and binding as the most important biological process and molecular function, respectively, in the responses of PM10-exposed patients with COPD. Biomarkers for PM10 in COPD were identified and compared with the same in healthy controls and included proteoglycan 4 (PRG4), inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4), and apolipoprotein F (APOF). PRG4 and ITIH4 were associated with a past 3-year PM10 exposure level. The receiver operating characteristic curve analysis showed that ITIH4 is a sensitive and specific biomarker for PM10 exposure (area under the curve [AUC] =0.690, P=0.015) compared with PRG4 (AUC =0.636, P=0.083), APOF (AUC =0.523, P=0.766), 8-isoprostane (AUC =0.563, P=0.405), and C-reactive protein (CRP; AUC =0.634, P=0.086). ITIH4 levels were correlated with CRP (r=0.353, P=0.005), suggesting that ITIH4 may be involved in an inflammatory mechanism. In summary, serum ITIH4 may be a PM10-specific biomarker in COPD and may be related to inflammation. PMID:25977605

  4. Friction and wear of sintered Alpha SiC sliding against IN-718 alloy at 25 to 800 C in atmospheric air at ambient pressure

    NASA Technical Reports Server (NTRS)

    Deadmore, Daniel L.; Sliney, Harold E.

    1986-01-01

    The sliding friction and wear of the SiC-nickel based alloy IN-718 couple under line contact test conditions in atmospheric air at a linear velocity of 0.18 m/sec and a load of 6.8 kg (67N) was investigated at temperatures of 25 to 800 C. It was found that the coefficient of friction was 0.6 up to 350 C then decreased to 0.3 at 500 and 800 C. It is suggested that the sharp decrease in the friction in the range of 350 to 550 C is due to the lubrication value of oxidation products. The wear rate reaches a minimum of 1 x 10 to the -10 to 2 x 10 to the -10 cu cm/cm/kg at 400 to 600 C.

  5. An assessment of the performance of the Monitor for AeRosols and GAses in ambient air (MARGA): a semi-continuous method for soluble compounds

    NASA Astrophysics Data System (ADS)

    Rumsey, I. C.; Cowen, K.; Kelly, T.; Hanft, E.; Mishoe, K.; Rogers, C.; Proost, R.; Lear, G.; Frelink, T.; Walker, J. T.

    2011-12-01

    Ambient air monitoring as part of the U.S. EPA's Clean Air Status and Trends Network (CASTNet) currently uses filter packs to measure weekly integrated concentrations. The U.S. EPA is interested in supplementing CASTNet with semi-continuous monitoring systems at select sites to examine ecosystem exposure to nitrogen and sulfur compounds at higher time resolution and with greater accuracy than the filter pack. The Monitor for AeRosols and GAses in ambient air (MARGA) measures water-soluble gases and aerosols at hourly temporal resolution. The performance of the MARGA was assessed under the U.S. EPA Environmental Technology Verification (ETV) program. The assessment was conducted in Research Triangle Park, NC from September 8th-October 8th, 2010. Precision of the MARGA was evaluated by comparing duplicate units and accuracy was evaluated by comparing duplicate MARGAs to duplicate reference denuder/filter packs. The MARGA utilizes a Wet Rotating Denuder (WRD) to collect gases, while aerosols are collected by a Steam Jet Aerosol Collector (SJAC). Both the WRD and the SJAC produce aqueous sample streams, which are analyzed by online ion chromatography for anions and cations. The reference denuder/filter pack consisted of sodium carbonate (Na2CO3) and phosphorous acid (H3PO3) coated denuders followed by a Teflon filter, a nylon filter, and a citric acid coated cellulose filter. The assessment of the MARGA units focused on gaseous SO2, HNO3 and NH3 and aerosol SO4-, NO3- and NH4+. To evaluate accuracy, hourly MARGA concentrations were averaged over 12 hours to match with 12-hour integrated concentrations from the reference system. The concentrations were compared using linear regression with performance goals of slope between 0.8-1.2 and y-intercept between -10 ppb and 10 ppb. Accuracy was further quantified as the median absolute relative percent difference (MARPD) between 12-hour MARGA and reference concentrations, with a performance goal of ≤ 40%. The precision of

  6. A Graphical Method for Estimation of Barometric Efficiency from Continuous Data - Concepts and Application to a Site in the Piedmont, Air Force Plant 6, Marietta, Georgia

    USGS Publications Warehouse

    Gonthier, Gerard J.

    2007-01-01

    A graphical method that uses continuous water-level and barometric-pressure data was developed to estimate barometric efficiency. A plot of nearly continuous water level (on the y-axis), as a function of nearly continuous barometric pressure (on the x-axis), will plot as a line curved into a series of connected elliptical loops. Each loop represents a barometric-pressure fluctuation. The negative of the slope of the major axis of an elliptical loop will be the ratio of water-level change to barometric-pressure change, which is the sum of the barometric efficiency plus the error. The negative of the slope of the preferred orientation of many elliptical loops is an estimate of the barometric efficiency. The slope of the preferred orientation of many elliptical loops is approximately the median of the slopes of the major axes of the elliptical loops. If water-level change that is not caused by barometric-pressure change does not correlate with barometric-pressure change, the probability that the error will be greater than zero will be the same as the probability that it will be less than zero. As a result, the negative of the median of the slopes for many loops will be close to the barometric efficiency. The graphical method provided a rapid assessment of whether a well was affected by barometric-pressure change and also provided a rapid estimate of barometric efficiency. The graphical method was used to assess which wells at Air Force Plant 6, Marietta, Georgia, had water levels affected by barometric-pressure changes during a 2003 constant-discharge aquifer test. The graphical method was also used to estimate barometric efficiency. Barometric-efficiency estimates from the graphical method were compared to those of four other methods: average of ratios, median of ratios, Clark, and slope. The two methods (the graphical and median-of-ratios methods) that used the median values of water-level change divided by barometric-pressure change appeared to be most resistant to

  7. An assessment of the performance of Monitor for AeRosols and GAses in ambient air (MARGA): a semi-continuous method for soluble compounds

    EPA Science Inventory

    Ambient air monitoring as part of the U.S. Environmental Protection Agency’s (U.S. EPA’s) Clean Air Status and Trends Network (CASTNet) currently uses filter packs to measure weekly integrated concentrations. The U.S. EPA is interested in supplementing CASTNet with semi-continuou...

  8. Alpha-1 Antitrypsin Deficiency

    MedlinePlus

    ... from the NHLBI on Twitter. What Is Alpha-1 Antitrypsin Deficiency? Alpha-1 antitrypsin (an-tee-TRIP-sin) deficiency, or AAT ... as it relates to lung disease. Overview Alpha-1 antitrypsin, also called AAT, is a protein made ...

  9. Single and double grid long-range alpha detectors

    DOEpatents

    MacArthur, Duncan W.; Allander, Krag S.

    1993-01-01

    Alpha particle detectors capable of detecting alpha radiation from distant sources. In one embodiment, a voltage is generated in a single electrically conductive grid while a fan draws air containing air molecules ionized by alpha particles through an air passage and across the conductive grid. The current in the conductive grid can be detected and used for measurement or alarm. Another embodiment builds on this concept and provides an additional grid so that air ions of both polarities can be detected. The detector can be used in many applications, such as for pipe or duct, tank, or soil sample monitoring.

  10. Single and double grid long-range alpha detectors

    DOEpatents

    MacArthur, D.W.; Allander, K.S.

    1993-03-16

    Alpha particle detectors capable of detecting alpha radiation from distant sources. In one embodiment, a voltage is generated in a single electrically conductive grid while a fan draws air containing air molecules ionized by alpha particles through an air passage and across the conductive grid. The current in the conductive grid can be detected and used for measurement or alarm. Another embodiment builds on this concept and provides an additional grid so that air ions of both polarities can be detected. The detector can be used in many applications, such as for pipe or duct, tank, or soil sample monitoring.

  11. A method of discriminating transuranic radionuclides from radon progeny using low-resolution alpha spectroscopy and curve-fitting techniques.

    PubMed

    Konzen, Kevin; Brey, Richard

    2012-05-01

    ²²²Rn (radon) and ²²⁰Rn (thoron) progeny are known to interfere with determining the presence of long-lived transuranic radionuclides, such as plutonium and americium, and require from several hours up to several days for conclusive results. Methods are proposed that should expedite the analysis of air samples for determining the amount of transuranic radionuclides present using low-resolution alpha spectroscopy systems available from typical alpha continuous air monitors (CAMs) with multi-channel analyzer (MCA) capabilities. An alpha spectra simulation program was developed in Microsoft Excel visual basic that employed the use of Monte Carlo numerical methods and serial-decay differential equations that resembled actual spectra. Transuranic radionuclides were able to be quantified with statistical certainty by applying peak fitting equations using the method of least squares. Initial favorable results were achieved when samples containing radon progeny were decayed 15 to 30 min, and samples containing both radon and thoron progeny were decayed at least 60 min. The effort indicates that timely decisions can be made when determining transuranic activity using available alpha CAMs with alpha spectroscopy capabilities for counting retrospective air samples if accompanied by analyses that consider the characteristics of serial decay.

  12. High gas flow alpha detector

    DOEpatents

    Bolton, Richard D.; Bounds, John A.; Rawool-Sullivan, Mohini W.

    1996-01-01

    An alpha detector for application in areas of high velocity gas flows, such as smokestacks and air vents. A plurality of spaced apart signal collectors are placed inside an enclosure, which would include smokestacks and air vents, in sufficient numbers to substantially span said enclosure so that gas ions generated within the gas flow are electrostatically captured by the signal collector means. Electrometer means and a voltage source are connected to the signal collectors to generate an electrical field between adjacent signal collectors, and to indicate a current produced through collection of the gas ions by the signal collectors.

  13. High gas flow alpha detector

    DOEpatents

    Bolton, R.D.; Bounds, J.A.; Rawool-Sullivan, M.W.

    1996-05-07

    An alpha detector for application in areas of high velocity gas flows, such as smokestacks and air vents. A plurality of spaced apart signal collectors are placed inside an enclosure, which would include smokestacks and air vents, in sufficient numbers to substantially span said enclosure so that gas ions generated within the gas flow are electrostatically captured by the signal collector means. Electrometer means and a voltage source are connected to the signal collectors to generate an electrical field between adjacent signal collectors, and to indicate a current produced through collection of the gas ions by the signal collectors. 4 figs.

  14. Influence of high past lead-in-air exposures on the lead-in-blood levels of lead-acid battery workers with continuing exposure.

    PubMed

    Hodgkins, D G; Hinkamp, D L; Robins, T G; Schork, M A; Krebs, W H

    1991-07-01

    We investigated the relationship between air lead levels and blood lead levels in 132 lead-acid battery workers in two plants who were followed for 30 months between 1983 and 1985 with frequent air lead and blood lead determinations. Both plants converted to more modern, expanded-metal battery manufacturing technologies around 1978 with associated reductions in mean air lead exposures from greater than 100 to less than 30 micrograms/m3. In multiple regression analyses including consideration of job category, seniority, age, ethnicity, gender, and smoking habit as covariates, there was a highly significant association of blood lead in micrograms/dL with air lead in micrograms/m3 (partial R2 = .20, P less than .0001) among the 68 workers in plant B but no association (P = .91) in plant A. Restriction of the regression analysis to those 44 workers in plant B with less than or equal to 22 years of seniority yielded the most significant air lead-blood lead association (partial R2 = .36, P less than .0001). Among the remaining 24 plant B workers, seniority, but not air lead, had a significant positive association with blood lead. Despite very stable air lead levels over the 30-month study, the 51 workers in plant A with more than 20 years' seniority had a mean decline of 0.04 microgram/dL in mean blood lead over the study period, whereas the 13 workers in plant A with less than or equal to 20 years' seniority had a mean increase of 7.6 microgram/dL.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. NACA Physicist Studying Alpha Rays

    NASA Technical Reports Server (NTRS)

    1957-01-01

    NACA Physicits studying Alpha Rays in a continuous cloud chamber. A cloud chamber is used by Lewis scientists to obtain information aimed at minimizing undesirable effects of radiation on nuclear-powered aircraft components. Here, alpha particles from a polonium source emit in a flower-like pattern at the cloud chamber's center. The particles are made visible by means of alcohol vapor diffusing from an area at room temperature to an area at minus -78 deg. Centigrade. Nuclear-powered aircraft were never developed and aircraft nuclear propulsion systems were canceled in the early 1960s.

  16. Radon exchange dynamics in a karst system investigated by radon continuous measurements in water: first results.

    PubMed

    Peano, G; Vigna, B; Villavecchia, E; Agnesod, G

    2011-05-01

    In 2008 the underground Karst Laboratory of Bossea Cave started research on radon exchange dynamics between bedrock, cave waters (main collector and percolations) and indoor underground atmosphere. Radon air concentrations, normally high, increase more and more during the collector's floods. An explanation of this is a radon-water solubilisation process more effective in flood events, because of a greater rock-water contact surface. Radon is then carried by water into the cave and released into the air. To verify this, continuous measurements of radon concentration are needed not only in the air, but also in the waters of the cave. So a new device for continuous radon monitoring in water was tested, connected to the AlphaGuard radon monitor. For the first 6 months of 2010, for different sections of the cave, the correlations between radon in the air, radon in the waters and the collector's stream flow fluctuations were presented and discussed. PMID:21586541

  17. FIELD METHOD COMPARISON BETWEEN PASSIVE AIR SAMPLERS AND CONTINUOUS MONITORS FOR VOLATILE ORGANIC COMPOUNDS AND NO2 IN EL PASO, TEXAS, USA

    EPA Science Inventory

    Passive sampling of gas-phase air toxics and criteria pollutants has become an attractive monitoring method in human exposure studies due to the relatively low sampling cost and ease of use. This study evaluates the performance of Model 3300 Ogawa(TM) Passive NO2 Samplers and 3...

  18. Alternating current long range alpha particle detector

    DOEpatents

    MacArthur, D.W.; McAtee, J.L.

    1993-02-16

    An alpha particle detector, utilizing alternating currents, which is capable of detecting alpha particles from distinct sources. The use of alternating currents allows use of simpler ac circuits which, in turn, are not susceptible to dc error components. It also allows the benefit of gas gain, if desired. In the invention, a voltage source creates an electric field between two conductive grids, and between the grids and a conductive enclosure. Air containing air ions created by collision with alpha particles is drawn into the enclosure and detected. In some embodiments, the air flow into the enclosure is interrupted, creating an alternating flow of ions. In another embodiment, a modulated voltage is applied to the grid, also modulating the detection of ions.

  19. Alternating current long range alpha particle detector

    DOEpatents

    MacArthur, Duncan W.; McAtee, James L.

    1993-01-01

    An alpha particle detector, utilizing alternating currents, whcih is capable of detecting alpha particles from distinct sources. The use of alternating currents allows use of simpler ac circuits which, in turn, are not susceptible to dc error components. It also allows the benefit of gas gain, if desired. In the invention, a voltage source creates an electric field between two conductive grids, and between the grids and a conductive enclosure. Air containing air ions created by collision with alpha particles is drawn into the enclosure and detected. In some embodiments, the air flow into the enclosure is interrupted, creating an alternating flow of ions. In another embodiment, a modulated voltage is applied to the grid, also modulating the detection of ions.

  20. Alpha Magnetic Spectrometer

    NASA Astrophysics Data System (ADS)

    Ting, Samuel

    2012-07-01

    The Alpha Magnetic Spectrometer (AMS) is a precision particle physics magnetic spectrometer designed to measure electrons, positrons, gamma rays and various nuclei and anti-nuclei from the cosmos up to TeV energy ranges. AMS weighs 7.5 tons and measures 5 meters by 4 meters by 3 meters. It contains 300,000 channels of electronics and 650 onboard microprocessors. It was delivered to the International Space Station onboard space shuttle Endeavour and installed on May 19, 2011. Since that time, more than 14 billion cosmic ray events have been collected. All the detectors function properly. At this moment, we are actively engaged in data analysis. AMS is an international collaboration involving 16 countries and 60 institutes. It took 16 years to construct and test. AMS is the only major physical science experiment on the International Space Station and will continue to collect data over the entire lifetime of the Space Station (10-20 years).

  1. Comparative study regarding the association of alpha-2U globulin with the nephrotoxic mechanism of certain petroleum-based Air Force fuels. Final report, 1 September 1986-31 August 1987

    SciTech Connect

    Eurell, T.E.

    1987-10-27

    Alpha-2U globulin is a low-molecular-weight urinary protein which may be associated with a hydrocarbon-induced proximal tubular cell degeneration in the male rat kidney. A new method was developed to obtain monospecific immunologic reagents for alpha-2U globulin using diafiltration, anion exchange and hydroxylapatite chromatography. Isoelectric focusing techniques were developed to isolate the major isoelectric variants of the alpha-2U globulin molecule and to assess changes in alpha-2U globulin after experimental exposure to hydrocarbon compounds. Alpha-2U globulin was isolated from the urine of albino and pigmented male rats to study strain susceptibility to the nephrotoxic process. An alpha-2u globulin isoelectric variant profile distinguishing albino from non-albino male rats was not apparent, however, strain differences were revealed. Fischer 344 male rats appear to have higher levels of the isoelectric variants than the other strains studied. These findings suggest that if a strain susceptibility to the hydrocarbon-induced nephrotoxic lesion exists, it may be associated with the alpha-2U globulin isoelectric variant profile.

  2. Ab initio alpha-alpha scattering.

    PubMed

    Elhatisari, Serdar; Lee, Dean; Rupak, Gautam; Epelbaum, Evgeny; Krebs, Hermann; Lähde, Timo A; Luu, Thomas; Meißner, Ulf-G

    2015-12-01

    Processes such as the scattering of alpha particles ((4)He), the triple-alpha reaction, and alpha capture play a major role in stellar nucleosynthesis. In particular, alpha capture on carbon determines the ratio of carbon to oxygen during helium burning, and affects subsequent carbon, neon, oxygen, and silicon burning stages. It also substantially affects models of thermonuclear type Ia supernovae, owing to carbon detonation in accreting carbon-oxygen white-dwarf stars. In these reactions, the accurate calculation of the elastic scattering of alpha particles and alpha-like nuclei--nuclei with even and equal numbers of protons and neutrons--is important for understanding background and resonant scattering contributions. First-principles calculations of processes involving alpha particles and alpha-like nuclei have so far been impractical, owing to the exponential growth of the number of computational operations with the number of particles. Here we describe an ab initio calculation of alpha-alpha scattering that uses lattice Monte Carlo simulations. We use lattice effective field theory to describe the low-energy interactions of protons and neutrons, and apply a technique called the 'adiabatic projection method' to reduce the eight-body system to a two-cluster system. We take advantage of the computational efficiency and the more favourable scaling with system size of auxiliary-field Monte Carlo simulations to compute an ab initio effective Hamiltonian for the two clusters. We find promising agreement between lattice results and experimental phase shifts for s-wave and d-wave scattering. The approximately quadratic scaling of computational operations with particle number suggests that it should be possible to compute alpha scattering and capture on carbon and oxygen in the near future. The methods described here can be applied to ultracold atomic few-body systems as well as to hadronic systems using lattice quantum chromodynamics to describe the interactions of

  3. Ab initio alpha-alpha scattering.

    PubMed

    Elhatisari, Serdar; Lee, Dean; Rupak, Gautam; Epelbaum, Evgeny; Krebs, Hermann; Lähde, Timo A; Luu, Thomas; Meißner, Ulf-G

    2015-12-01

    Processes such as the scattering of alpha particles ((4)He), the triple-alpha reaction, and alpha capture play a major role in stellar nucleosynthesis. In particular, alpha capture on carbon determines the ratio of carbon to oxygen during helium burning, and affects subsequent carbon, neon, oxygen, and silicon burning stages. It also substantially affects models of thermonuclear type Ia supernovae, owing to carbon detonation in accreting carbon-oxygen white-dwarf stars. In these reactions, the accurate calculation of the elastic scattering of alpha particles and alpha-like nuclei--nuclei with even and equal numbers of protons and neutrons--is important for understanding background and resonant scattering contributions. First-principles calculations of processes involving alpha particles and alpha-like nuclei have so far been impractical, owing to the exponential growth of the number of computational operations with the number of particles. Here we describe an ab initio calculation of alpha-alpha scattering that uses lattice Monte Carlo simulations. We use lattice effective field theory to describe the low-energy interactions of protons and neutrons, and apply a technique called the 'adiabatic projection method' to reduce the eight-body system to a two-cluster system. We take advantage of the computational efficiency and the more favourable scaling with system size of auxiliary-field Monte Carlo simulations to compute an ab initio effective Hamiltonian for the two clusters. We find promising agreement between lattice results and experimental phase shifts for s-wave and d-wave scattering. The approximately quadratic scaling of computational operations with particle number suggests that it should be possible to compute alpha scattering and capture on carbon and oxygen in the near future. The methods described here can be applied to ultracold atomic few-body systems as well as to hadronic systems using lattice quantum chromodynamics to describe the interactions of

  4. alpha-Hexachlorocyclohexane (alpha-HCH)

    Integrated Risk Information System (IRIS)

    alpha - Hexachlorocyclohexane ( alpha - HCH ) ; CASRN 319 - 84 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Ass

  5. Alpha-1 Antitrypsin Test

    MedlinePlus

    ... measures the level of the protein AAT in blood. Alpha-1 antitrypsin phenotype testing evaluates the amount and type of AAT being produced and compares it to normal patterns. Alpha-1 antitrypsin genotype testing ( DNA testing) can ...

  6. Alpha-1 antitrypsin test

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003715.htm Alpha-1 antitrypsin test To use the sharing features on this page, please enable JavaScript. Alpha-1 antitrypsin is a laboratory test to measure the ...

  7. Production of tumor necrosis factor alpha, interleukin-1 alpha, and interleukin-6 during murine coccidioidomycosis.

    PubMed Central

    Cox, R A; Magee, D M

    1995-01-01

    The proinflammatory cytokines tumor necrosis factor alpha (TNF-alpha), interleukin-1 alpha (IL-1 alpha), and interleukin-6 (IL-6) were induced in mice infected with Coccidioides immitis. Analyses of the cytokine profiles of two inbred mouse strains which differ in their susceptibility to pulmonary challenge with C. immitis revealed higher levels of IL-6 in lungs from DBA/2 mice (resistant strain) than in those from BALB/c mice (susceptible strain) beginning at day 6 and continuing through day 15 postinfection. Spleen cells from both mouse strains secreted TNF-alpha, IL-1 alpha, and IL-6 in vitro in response to stimulation with killed spherules but differed in that spleen cells from the resistant strain produced increased levels of these cytokines earlier after pulmonary challenge and at increased levels throughout the course of the disease. PMID:7558338

  8. The Alpha Centauri System.

    ERIC Educational Resources Information Center

    Soderblom, David R.

    1987-01-01

    Describes the Alpha Centauri star system, which is the closest star system to the sun. Discusses the difficulties associated with measurements involving Alpha Centauri, along with some of the recent advances in stellar seismology. Raises questions about the possibilities of planets around Alpha Centauri. (TW)

  9. A New Solar H-alpha Distributed Observing System

    NASA Astrophysics Data System (ADS)

    Hill, Frank; Harvey, J. W.; Luis, G.; Purdy, T.; Bolding, J.; Eliason, P.; Kroll, R.; Lewis, F.; Berman, L.; Parsons, A.

    2009-05-01

    Space weather forecasts and nowcasts require rapid-cadence, continual, and robust solar observations. A useful strategy to accomplish this is to deploy a network of ground-based observing systems distributed in geographic longitude. The US Air Force Weather Agency (AFWA) has been operating the Solar Optical Observing Network (SOON) for many years, and is now replacing SOON with ISOON, an improved SOON. As a back-up during the development and installation of ISOON, AFWA is supporting the addition of an H-alpha observing system into the existing sites of the Global Oscillation Network Group (GONG) program. GONG comprises six sites in California, Hawaii, Australia, India, Spain, and Chile, and currently provides one per minute continual magnetic field, Doppler, and intensity measurements in the Ni 6768 line. The additional H-alpha capability will comprise a 0.4-A bandpass filter, a 2kX2k CCD, beamsplitter, transfer optics, and a dedicated data acquisition system. The observing cadence will be one per minute at a given site, with the acquisition time shifted between adjacent sites to potentially provide an image every 20 sec. The data will be transmitted back to Tucson, processed, and then transferred to AFWA within one minute of acquisition.

  10. Atlantic mercury emission determined from continuous analysis of the elemental mercury sea-air concentration difference within transects between 50°N and 50°S

    NASA Astrophysics Data System (ADS)

    Kuss, J.; Zülicke, C.; Pohl, C.; Schneider, B.

    2011-09-01

    Mercury in the environment deserves serious concern because of the mobility of volatile elemental mercury (Hg0) in the atmosphere, in combination with the harmful effect of Hg compounds on human health and the ecosystem. A major source of global atmospheric mercury is presumed to be oceanic Hg0 emission. However, available Hg0 surface water data to reliably estimate the ocean's mercury emissions are sparse. In this study, high-resolution surface water and air measurements of Hg0 were carried out between Europe and South Africa in November 2008 and between South America and Europe in April-May 2009. On each cruise a strong enrichment of Hg0 in tropical surface water was determined that apparently followed the seasonal shift of the Intertropical Convergence Zone (ITCZ). A combination of a high Hg0 production rate constant and the actual low wind speeds, which prevented emission, probably caused the accumulation of Hg0 in surface waters of the ITCZ. Hg0 emissions in the tropics were significant only if wind speed variability on a monthly scale was considered, in which case the observed significant decline of total Hg in tropical surface waters during the northern winter could be explained. In the midlatitudes, increased autumn Hg0 emissions were calculated for November in the Northern Hemisphere and for May in the Southern Hemisphere; conversely, emissions were low during both the northern and the southern spring. Mercury removal from surface waters by Hg0 emission and sinking particles was comparable to its supply through wet and dry deposition.

  11. Selective flow path alpha particle detector and method of use

    DOEpatents

    Orr, Christopher Henry; Luff, Craig Janson; Dockray, Thomas; Macarthur, Duncan Whittemore

    2002-01-01

    A method and apparatus for monitoring alpha contamination are provided in which ions generated in the air surrounding the item, by the passage of alpha particles, are moved to a distant detector location. The parts of the item from which ions are withdrawn can be controlled by restricting the air flow over different portions of the apparatus. In this way, detection of internal and external surfaces separately, for instance, can be provided. The apparatus and method are particularly suited for use in undertaking alpha contamination measurements during the commissioning operations.

  12. Radon discrimination for work place air samples

    SciTech Connect

    Bratvold, T.

    1994-09-27

    Gross alpha/beta measurement systems are designed solely to identify an incident particle as either an alpha or a beta and register a count accordingly. The tool of choice for radon identification, via decay daughters, is an instrument capable of identifying the energy of incident alpha particles and storing that information separately from detected alpha emissions of different energy. In simpler terms, the desired instrument is an alpha spectroscopy system. K Basins Radiological Control (KBRC) procured an EG&G ORTEC OCTETE PC alpha spectroscopy system to facilitate radon identification on work place air samples. The alpha spectrometer allows for the identification of any alpha emitting isotope based on characteristic alpha emission energies. With this new capability, KBRC will explicitly know whether or not there exists a true airborne concern. Based on historical air quality data, this new information venue will reduce the use of respirators substantially. Situations where an area remains ``on mask`` due solely to the presence of radon daughters on the grab air filter will finally be eliminated. This document serves to introduce a new method for radon daughter detection at the 183KE Health Physics Analytical Laboratory (HPAL). A new work place air sampling analysis program will be described throughout this paper. There is no new technology being introduced, nor any unproven analytical process. The program defined over the expanse of this document simply explains how K Basins Radiological Control will employ their alpha spectrometer.

  13. Overview Of Suborbital Human Transportation Concept Alpha

    NASA Astrophysics Data System (ADS)

    Adirim, H.; Pilz, N.; Marini, M.; Hendrick, P.; Schmid, M.; Behr, R.; Barth, T.; Tarfeld, F.; Wiegand, A.; Charbonnier, D.; Haya Ramos, R.; Steeland, J.; Mack, A.

    2011-05-01

    Within the EC co-funded project FAST20XX (Future high-Altitude high-Speed Transport 20XX), the European suborbital passenger transportation system concept ALPHA (Airplane Launched PHoenix Aircraft), which shall be based to a maximum extent on existing technologies and capabilities, is currently being investigated as collaborative project by a European consortium under coordination of ESA. The ALPHA concept incorporates an air-launch from a carrier aircraft, which shall be used as first stage. The ALPHA vehicle shall be capable of transporting up to four passengers plus one pilot to an altitude of at least 100 km. The ALPHA vehicle is a down-scaled version of the suborbital space transportation concept Hopper, which was already deeply investigated within the European FESTIP System Study and the German ASTRA program including the successfully flown experimental landing demonstrator Phoenix. This approach has allowed the use of existing aerodynamic vehicle data and has led to the adaptation of the external Hopper/Phoenix configuration for ALPHA. In FESTIP and ASTRA, the Hopper configuration showed sufficient stability margins. Due to the geometric similarity of the ALPHA and Hopper vehicles, a trimable and flyable configuration could be derived by means of ALPHA flight trajectory calculations. In its current configuration, the ALPHA vehicle has a length of ca. 9 m and a gross take-off mass of ca. 3.5 Mg. The launch, staging and separation of ALPHA shall be performed either as internal air-launch from the cargo bay of the carrier aircraft, as under-wing air-launch or as towed air-launch. After separation from the carrier aircraft, the ALPHA vehicle ignites its onboard rocket propulsion system. Since conventional liquid and solid propulsion did not seem suitable for ALPHA due to Their high cost, limited safety and toxicity, a low-cost, “green” and non-hazardous hybrid propulsion system based on liquid nitrous oxide in combination with a solid polymer fuel was

  14. Fan-less long range alpha detector

    DOEpatents

    MacArthur, Duncan W.; Bounds, John A.

    1994-01-01

    A fan-less long range alpha detector which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces.

  15. Fan-less long range alpha detector

    DOEpatents

    MacArthur, D.W.; Bounds, J.A.

    1994-05-10

    A fan-less long range alpha detector is disclosed which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces. 2 figures.

  16. Use of Chiral Signatures of Organochlorine Pesticides in Asian, Trans-Pacific, and Western U.S. Air Masses to Identify Source Regions

    NASA Astrophysics Data System (ADS)

    Simonich, S.; Genualdi, S.; Primbs, T.; Ryoo, K.; Bidleman, T.; Jantunen, L.

    2008-12-01

    Chiral signatures of organochlorine pesticides were measured in air masses on Okinawa Japan and three remote locations in the Pacific Northwestern U.S.: Cheeka Peak Observatory (CPO), a coastal site on the Olympic Peninsula of Washington at 500 m; Mary's Peak Observatory (MPO), a site at 1250 m in Oregon's Coast range; and Mt. Bachelor Observatory (MBO), a site at 2300 m in Oregon's Cascade range. The chiral signature of composite soil samples collected from agricultural areas in China and South Korea were also measured. Racemic alpha-HCH was measured in Asian air masses and soil from China and South Korea. Non-racemic (enantiomer fraction (EF) = 0.528 ± 0.0048) alpha-HCH was measured in regional air masses at CPO, a marine boundary layer site, and may reflect volatilization from the Pacific Ocean and regional soils. However, during trans-Pacific transport events at CPO, the EFs were significantly (p-value <0.001) more racemic (EF = 0.513 ± 0.0003). Racemic alpha-HCH was consistently measured in trans- Pacific air masses at MPO and MBO. The alpha-HCH EFs in CPO, MPO, and MBO air masses were positively correlated (p-value = 0.0017) with the amount of time the air mass spent above the boundary layer along the 10-day back air mass trajectory prior to being sampled. This suggests that the alpha-HCH in the free troposphere is racemic. The racemic signatures of cis and trans chlordane in air masses at all four air sampling sites suggest that Asian and U.S. urban areas continue to be sources of chlordanes that have not yet undergone biotransformation.

  17. 40 CFR 63.9634 - How do I demonstrate continuous compliance with the emission limitations that apply to me?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air... similar air pollution control device applied to each similar emission unit within a defined group...

  18. The promoting effect of tumour necrosis factor alpha in radiation-induced cell transformation.

    PubMed Central

    Guo, R. F.; Gong, Y. F.

    1998-01-01

    The ability of tumour necrosis factor alpha (TNF-alpha), a potent endogenous inflammatory agent, to promote malignant transformation of Syrian hamster embryo cells (SHE) initiated by a 0.5-Gy dose of alpha-particles was investigated. Opsonized zymosan particles, which were phagocytosed by a human macrophage-like cell line, triggered TNF-alpha production from U937 cells. This cell supernatant could significantly increase the transformation frequency (TF) of primary SHE cells previously irradiated by a 0.5-Gy dose of alpha-particles. The TF decreased significantly if monoclonal antibody against TNF-alpha was added to the supernatant. Similarly, recombinant human TNF-alpha (rhTNF-alpha) increased the TF of alpha-irradiated primary SHE cells to an even greater extent. Addition of TNF-alpha to subcultures of irradiated SHE cells permitted the continuous propagation of these primary cells. In contrast, both TNF-alpha-treated control and alpha-irradiated cells without subsequent TNF-alpha treatment senesced after 7-15 passages. Irradiated SHE cells treated continuously with TNF-alpha could be subcultured over 40 passages and produced fibrosarcomas upon inoculation into nude mice. Our results provide the first evidence that TNF-alpha released by activated macrophages may contribute to the process of malignant transformation initiated by low-dose alpha-particles. PMID:9579824

  19. Determination of Alpha

    NASA Astrophysics Data System (ADS)

    Chmeissani, Mokhtar Abdallah

    The determination of the strong coupling constant alpha_ s, using Energy-Energy Correlation Asymmetry and jet mass difference with Mark II data at SLC (91 GeV) is presented. In Energy-Energy Correlation Asymmetry (EECA), we used the same systematic procedure used to determine alpha_ s with MARK II data at PEP (29 GeV). The chi^2 fit suggests that alpha_ s = 0.119 +/- 0.007(stat.) +/- 0.007(syst.). In addition, we used the EECA method to determine the QCD scale parameter Lambda_{LLA}. The chi^2 fit suggests that Lambda _{LLA} = 420 +/- 90(stat.) MeV. In the jet mass difference method, the determination of alpha_ s is based on QCD calculations up to 2nd order. We showed that in this method we are able to reproduce the value of alpha _ s from a Monte Carlo sample to a very high accuracy. The result with this method is alpha _ s = 0.134 +/- 0.085(stat.) +/- 0.004(syst.). The two values of alpha_ s presented in this work are in agreement within the error bars and in a good agreement with recent results of alpha_ s published from other e^+e^- experiments.

  20. Imaging alpha particle detector

    DOEpatents

    Anderson, D.F.

    1980-10-29

    A method and apparatus for detecting and imaging alpha particles sources is described. A dielectric coated high voltage electrode and a tungsten wire grid constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source to be quantitatively or qualitatively analyzed. A thin polyester film window allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods. A significant increase in sensitivity over other alpha particle detectors is observed, and the device has very low sensitivity to gamma or beta emissions which might otherwise appear as noise on the alpha particle signal.

  1. Imaging alpha particle detector

    DOEpatents

    Anderson, David F.

    1985-01-01

    A method and apparatus for detecting and imaging alpha particles sources is described. A conducting coated high voltage electrode (1) and a tungsten wire grid (2) constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source (3) to be quantitatively or qualitatively analyzed. A thin polyester film window (4) allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods. A significant increase in sensitivity over other alpha particle detectors is observed, and the device has very low sensitivity to gamma or beta emissions which might otherwise appear as noise on the alpha particle signal.

  2. Continuous Problem of Function Continuity

    ERIC Educational Resources Information Center

    Jayakody, Gaya; Zazkis, Rina

    2015-01-01

    We examine different definitions presented in textbooks and other mathematical sources for "continuity of a function at a point" and "continuous function" in the context of introductory level Calculus. We then identify problematic issues related to definitions of continuity and discontinuity: inconsistency and absence of…

  3. 29 CFR 1915.1004 - alpha-Naphthylamine.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false alpha-Naphthylamine. 1915.1004 Section 1915.1004 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... § 1915.1004 alpha-Naphthylamine. Note: The requirements applicable to shipyard employment under...

  4. 29 CFR 1910.1004 - alpha-Naphthylamine.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 6 2013-07-01 2013-07-01 false alpha-Naphthylamine. 1910.1004 Section 1910.1004 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... alpha-Naphthylamine. See § 1910.1003, 13 carcinogens....

  5. 29 CFR 1910.1004 - alpha-Naphthylamine.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 6 2012-07-01 2012-07-01 false alpha-Naphthylamine. 1910.1004 Section 1910.1004 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... alpha-Naphthylamine. See § 1910.1003, 13 carcinogens....

  6. 29 CFR 1910.1004 - alpha-Naphthylamine.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 6 2014-07-01 2013-07-01 true alpha-Naphthylamine. 1910.1004 Section 1910.1004 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... alpha-Naphthylamine. See § 1910.1003, 13 carcinogens....

  7. 29 CFR 1915.1004 - alpha-Naphthylamine.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false alpha-Naphthylamine. 1915.1004 Section 1915.1004 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... § 1915.1004 alpha-Naphthylamine. Note: The requirements applicable to shipyard employment under...

  8. 29 CFR 1915.1004 - alpha-Naphthylamine.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 7 2013-07-01 2013-07-01 false alpha-Naphthylamine. 1915.1004 Section 1915.1004 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... § 1915.1004 alpha-Naphthylamine. Note: The requirements applicable to shipyard employment under...

  9. Enantiomeric signatures of organochlorine pesticides in Asian, trans-Pacific, and western U.S. air masses.

    PubMed

    Genualdi, Susan A; Simonich, Staci L Massey; Primbs, Toby K; Bidleman, Terry F; Jantunen, Liisa M; Ryoo, Keon-Sang; Zhu, Tong

    2009-04-15

    The enantiomeric signatures of organochlorine pesticides were measured in air masses from Okinawa, Japan and three remote locations in the Pacific Northwestern United States: Cheeka Peak Observatory (CPO), a marine boundary layer site on the Olympic Peninsula of Washington at 500 m above sea level (m.a.s.l); Mary's Peak Observatory (MPO), a site at 1250 m.a.s.l in Oregon's Coast range; and Mt. Bachelor Observatory (MBO), a site at 2763 m.a.s.l in Oregon's Cascade range. The enantiomeric signatures of composite soil samples, collected from China, South Korea, and the western U.S. were also measured. The data from chiral analysis was expressed asthe enantiomeric fraction, defined as (+) enantiomer/(sum of the (+) and (-) enantiomers), where a racemic composition has EF = 0.5. Racemic alpha-hexachlorocyclohexane (alpha-HCH) was measured in Asian air masses at Okinawa and in Chinese and South Korean soils. Nonracemic alpha-HCH (EF = 0.528 +/- 0.0048) was measured in regional air masses at CPO, and may reflect volatilization from the Pacific Ocean and regional soils. However, during trans-Pacific transport events at CPO, the alpha-HCH EFs were significantly more racemic (EF = 0.513 +/- 0.0003, p < 0.001). Racemic alpha-HCH was consistently measured at MPO and MBO in trans-Pacific air masses that had spent considerable time in the free troposphere. The alpha-HCH EFs in CPO, MPO, and MBO air masses were negatively correlated (p = 0.0017) with the amount of time the air mass spent above the boundary layer, along the 10-day back air mass trajectory, prior to being sampled. This suggests that, on the West coast of the U.S., the alpha-HCH in the free troposphere is racemic. Racemic signatures of cis- and trans-chlordane were measured in air masses at all four air sampling sites, suggesting that Asian and U.S. urban areas continue to be sources of chlordane that has not yet been biotransformed. PMID:19475954

  10. Enantiomeric signatures of organochlorine pesticides in Asian, trans-Pacific, and western U.S. air masses.

    PubMed

    Genualdi, Susan A; Simonich, Staci L Massey; Primbs, Toby K; Bidleman, Terry F; Jantunen, Liisa M; Ryoo, Keon-Sang; Zhu, Tong

    2009-04-15

    The enantiomeric signatures of organochlorine pesticides were measured in air masses from Okinawa, Japan and three remote locations in the Pacific Northwestern United States: Cheeka Peak Observatory (CPO), a marine boundary layer site on the Olympic Peninsula of Washington at 500 m above sea level (m.a.s.l); Mary's Peak Observatory (MPO), a site at 1250 m.a.s.l in Oregon's Coast range; and Mt. Bachelor Observatory (MBO), a site at 2763 m.a.s.l in Oregon's Cascade range. The enantiomeric signatures of composite soil samples, collected from China, South Korea, and the western U.S. were also measured. The data from chiral analysis was expressed asthe enantiomeric fraction, defined as (+) enantiomer/(sum of the (+) and (-) enantiomers), where a racemic composition has EF = 0.5. Racemic alpha-hexachlorocyclohexane (alpha-HCH) was measured in Asian air masses at Okinawa and in Chinese and South Korean soils. Nonracemic alpha-HCH (EF = 0.528 +/- 0.0048) was measured in regional air masses at CPO, and may reflect volatilization from the Pacific Ocean and regional soils. However, during trans-Pacific transport events at CPO, the alpha-HCH EFs were significantly more racemic (EF = 0.513 +/- 0.0003, p < 0.001). Racemic alpha-HCH was consistently measured at MPO and MBO in trans-Pacific air masses that had spent considerable time in the free troposphere. The alpha-HCH EFs in CPO, MPO, and MBO air masses were negatively correlated (p = 0.0017) with the amount of time the air mass spent above the boundary layer, along the 10-day back air mass trajectory, prior to being sampled. This suggests that, on the West coast of the U.S., the alpha-HCH in the free troposphere is racemic. Racemic signatures of cis- and trans-chlordane were measured in air masses at all four air sampling sites, suggesting that Asian and U.S. urban areas continue to be sources of chlordane that has not yet been biotransformed.

  11. Concentrations of 222Rn, 220Rn and their decay products measured in outdoor air in various rural zones (Morocco) by using solid-state nuclear track detectors and resulting radiation dose to the rural populations.

    PubMed

    Misdaq, M A; Amrane, M; Ouguidi, J

    2010-03-01

    Alpha and beta activities per unit volume of air due to radon ((222)Rn), thoron ((220)Rn) and their progenies were measured in the outdoor air at different locations in Morocco by using both CR-39 and LR-115 type II solid-state nuclear track detectors (SSNTDs). In addition, the radon concentration was continuously measured in one location by using the methods with SSNTDs and AlphaGuard counter. The influence of the geological and meteorological conditions as well as phosphate and building material dust on the radon concentration in the outdoor air of the areas studied was investigated. The committed equivalent doses due to (218)Po and (214)Po radon short-lived progeny were evaluated in different tissues of the respiratory tract of the members of the public from the inhalation of outdoor air. The annual effective dose due to radon short-lived progeny from the inhalation of outdoor air by the members of the rural population was estimated.

  12. Alpha characterization inside pipes using ion-transport technology

    SciTech Connect

    Rojas, S.P.; Rawool-Sullivan, M.W.; Williams, K.G.; Vaccarella, J.A.

    1995-03-01

    Many DOE facilities have several miles of waste pipe systems that are internally contaminated with various and often undetermined radio nuclides. Unfortunately, currently acceptable alpha detection technologies are inefficient, time consuming, and do not address the problems presented by small diameter or curved pipes. In general, the problem of detecting alpha contamination on the inside surface of pipes is complicated by the fact that alphas do not penetrate the pipe walls. Unlike their conventional counterparts, alpha detectors based on ion transport technology sense alpha particles by collecting the ions created in ambient air as the particle loses its kinetic energy. The ions inside the pipe are transported by a fan-generated air current to an electrode inside the detector, which is attached to one end of the pipe. The collected charge at the electrode is proportional to the number of ions created inside the pipe, which in turn is proportional to the number of alphas emitted. Typically, monitoring for alpha contamination inside pipes or ductwork involves disrupting the operation to access as much surface area as possible for standard alpha monitoring. The detector based on ion transport technology effectively minimizes such disruption and in many circumstances will allow for in situ monitoring of a system that might otherwise not be practically accessible to standard methods.

  13. The alpha channeling effect

    SciTech Connect

    Fisch, N. J.

    2015-12-10

    Alpha particles born through fusion reactions in a tokamak reactor tend to slow down on electrons, but that could take up to hundreds of milliseconds. Before that happens, the energy in these alpha particles can destabilize on collisionless timescales toroidal Alfven modes and other waves, in a way deleterious to energy confinement. However, it has been speculated that this energy might be instead be channeled into useful energy, so as to heat fuel ions or to drive current. Such a channeling needs to be catalyzed by waves Waves can produce diffusion in energy of the alpha particles in a way that is strictly coupled to diffusion in space. If these diffusion paths in energy-position space point from high energy in the center to low energy on the periphery, then alpha particles will be cooled while forced to the periphery. The energy from the alpha particles is absorbed by the wave. The amplified wave can then heat ions or drive current. This process or paradigm for extracting alpha particle energy collisionlessly has been called alpha channeling. While the effect is speculative, the upside potential for economical fusion is immense. The paradigm also operates more generally in other contexts of magnetically confined plasma.

  14. Comparative study regarding the association of alpha-2u globulin with the nephrotoxic mechanism of certain petroleum-based air force fuels. Annual report 1 Jul 90-30 Jun 91

    SciTech Connect

    Eurell, T.E.

    1991-08-14

    Adult male rats have a dose and time dependent renal proximal tubular degeneration induced by certain hydrocarbon compounds. This degeneration is associated with a low molecular weight urinary protein called alpha 2U globulin. We are using rat strain variation (Fisher 344 and NCI Black Reiter) and different hydrocarbon compounds (JP-4, JP-8, decalin and trimethylpentane) to investigate the hydrocarbon-induced nephrotoxic response. Preliminary histochemical and morphometric evaluation of NCI-Black Reiter rats exposed to JP-8 suggests that this strain undergoes an intermediate form of the hydrocarbon-induced nephrotoxicity when compared to the albino Fisher 344 strain.

  15. Alpha One Foundation

    MedlinePlus

    ... related programs More News Our Number One Goal: Find a cure for Alpha-1. Website Sponsors Helpful Links 3300 Ponce de Leon Blvd. Coral Gables, FL 33134 Phone: (877) 228-7321 Email: info@alphaone.org Copyright ...

  16. 29 CFR 1910.1004 - alpha-Naphthylamine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 6 2010-07-01 2010-07-01 false alpha-Naphthylamine. 1910.1004 Section 1910.1004 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS (CONTINUED) Toxic and Hazardous Substances §...

  17. 29 CFR 1910.1004 - alpha-Naphthylamine.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 6 2011-07-01 2011-07-01 false alpha-Naphthylamine. 1910.1004 Section 1910.1004 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS (CONTINUED) Toxic and Hazardous Substances §...

  18. Alpha Particle Diagnostic

    SciTech Connect

    Fisher, Ray, K.

    2009-05-13

    The study of burning plasmas is the next frontier in fusion energy research, and will be a major objective of the U.S. fusion program through U.S. collaboration with our international partners on the ITER Project. For DT magnetic fusion to be useful for energy production, it is essential that the energetic alpha particles produced by the fusion reactions be confined long enough to deposit a significant fraction of their initial ~3.5 MeV energy in the plasma before they are lost. Development of diagnostics to study the behavior of energetic confined alpha particles is a very important if not essential part of burning plasma research. Despite the clear need for these measurements, development of diagnostics to study confined the fast confined alphas to date has proven extremely difficult, and the available techniques remain for the most part unproven and with significant uncertainties. Research under this grant had the goal of developing diagnostics of fast confined alphas, primarily based on measurements of the neutron and ion tails resulting from alpha particle knock-on collisions with the plasma deuterium and tritium fuel ions. One of the strengths of this approach is the ability to measure the alphas in the hot plasma core where the interesting ignition physics will occur.

  19. Fungal biofiltration of alpha-pinene: effects of temperature, relative humidity, and transient loads.

    PubMed

    Jin, Yaomin; Guo, Ling; Veiga, María C; Kennes, Christian

    2007-02-15

    Over the past decade much effort has been made to develop new carrier materials, more performant biocatalysts, and new types of bioreactors for waste gas treatment. In biofilters fungal biocatalysts are more resistant to acid and dry conditions and take up hydrophobic compounds from the gas phase more easily than wet bacterial biofilms. In the present study, a biofilter packed with a mixture of perlite and Pall rings and fed alpha-pinene-polluted air was inoculated with a new fungal isolate identified as Ophiostoma species. alpha-Pinene is a volatile pollutant typically found in waste gases from wood-related industries. The temperature of waste gas streams from pulp and paper industries containing alpha-pinene is usually higher than ambient temperature. Studies were undertaken here on the effect on performance of temperature changes in the range of 15-40 degrees C. The effect of temperature on biodegradation kinetics in continuous reactors was elucidated through equations derived from the Arrhenius formula. Moreover, the effects of the relative humidity (RH) of the inlet gas phase, transient loads (shock or starvation), and the nature of the nitrogen source on alpha-pinene removal were also studied in this research. The results suggest that the fungal biofilter appears to be an effective treatment process for the removal of alpha-pinene. The optimal conditions are: temperature around 30 degrees C, RH of the inlet waste gas stream around 85%, and nitrate as nitrogen source. The fungal biofilter also showed a good potential to withstand shock loads and recovered rapidly its full performance after a 3-7 days starvation period.

  20. Luminescence imaging of water during alpha particle irradiation

    NASA Astrophysics Data System (ADS)

    Yamamoto, Seiichi; Komori, Masataka; Koyama, Shuji; Toshito, Toshiyuki

    2016-05-01

    The luminescence imaging of water using the alpha particle irradiation of several MeV energy range is thought to be impossible because this alpha particle energy is far below the Cerenkov-light threshold and the secondary electrons produced in this energy range do not emit Cerenkov-light. Contrary to this consensus, we found that the luminescence imaging of water was possible with 5.5 MeV alpha particle irradiation. We placed a 2 MBq of 241Am alpha source in water, and luminescence images of the source were conducted with a high-sensitivity, cooled charge-coupled device (CCD) camera. We also carried out such imaging of the alpha source in three different conditions to compare the photon productions with that of water, in air, with a plastic scintillator, and an acrylic plate. The luminescence imaging of water was observed from 10 to 20 s acquisition, and the intensity was linearly increased with time. The intensity of the luminescence with the alpha irradiation of water was 0.05% of that with the plastic scintillator, 4% with air, and 15% with the acrylic plate. The resolution of the luminescence image of water was better than 0.25 mm FWHM. Alpha particles of 5.5 MeV energy emit luminescence in water. Although the intensity of the luminescence was smaller than that in air, it was clearly observable. The luminescence of water with alpha particles would be a new method for alpha particle detection and distribution measurements in water.

  1. Performance of an in-situ alpha spectrometer.

    PubMed

    Pöllänen, R

    2016-03-01

    Equipment was recently developed for detecting alpha particles from flat and smooth surfaces with good energy resolution at ambient air pressure. In this work, the detection efficiencies were determined using different extended-area sources emitting alpha and beta radiation and a mixed nuclide point source emitting alpha radiation. Beta particles are of importance because they can also be detected. Counts originating from alpha and beta particles are mainly at different energies, which make their separation possible. An efficiency of 0.14 was determined for an extended-area (>30cm(2)) homogeneous source emitting alpha radiation at the energy of 5-6MeV, whereas for the beta emitters the efficiencies were 0.07-0.19 depending on the beta-particle emission energies. The use of a collimator reduces the detection efficiencies by a factor of up to ten. PMID:26688356

  2. 21 CFR 866.5620 - Alpha-2-macroglobulin immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5620 Alpha-2-macroglobulin immunological test system. (a) Identification. An alpha-2-macroglobulin... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Alpha-2-macroglobulin immunological test...

  3. 21 CFR 866.5400 - Alpha-globulin immuno-logical test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5400 Alpha-globulin immuno-logical test system. (a) Identification. An alpha-globulin immunological... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Alpha-globulin immuno-logical test system....

  4. 21 CFR 866.5620 - Alpha-2-macroglobulin immunological test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5620 Alpha-2-macroglobulin immunological test system. (a) Identification. An alpha-2-macroglobulin... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Alpha-2-macroglobulin immunological test...

  5. 21 CFR 866.5130 - Alpha-1-antitrypsin immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5130 Alpha-1-antitrypsin immunological test system. (a) Identification. An alpha-1-antitrypsin... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Alpha-1-antitrypsin immunological test system....

  6. 21 CFR 866.5580 - Alpha-1-lipoprotein immuno-logical test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5580 Alpha-1-lipoprotein immuno-logical test system. (a) Identification. An alpha-1-lipoprotein... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Alpha-1-lipoprotein immuno-logical test...

  7. 21 CFR 866.5580 - Alpha-1-lipoprotein immuno-logical test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5580 Alpha-1-lipoprotein immuno-logical test system. (a) Identification. An alpha-1-lipoprotein... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Alpha-1-lipoprotein immuno-logical test...

  8. Time variations of 222Rn concentration and air exchange rates in a Hungarian cave.

    PubMed

    Nagy, Hedvig Éva; Szabó, Zsuzsanna; Jordán, Gyozo; Szabó, Csaba; Horváth, Akos; Kiss, Attila

    2012-09-01

    A long-term radon concentration monitoring was carried out in the Pál-völgy cave, Budapest, Hungary, for 1.5 years. Our major goal was to determine the time dependence of the radon concentration in the cave to characterise the air exchange and define the most important environmental parameters that influence the radon concentration inside the cave. The radon concentration in the cave air was measured continuously by an AlphaGuard radon monitor, and meteorological parameters outside the cave were collected simultaneously. The air's radon concentration in the cave varied between 104 and 7776 Bq m(-3), the annual average value was 1884±85 Bq m(-3). The summer to winter radon concentration ratio was as high as 21.8. The outside air temperature showed the strongest correlation with the radon concentration in the cave, the correlation coefficient (R) was 0.76. PMID:22462600

  9. Apparatus for detecting alpha radiation in difficult access areas

    DOEpatents

    Steadman, P.; MacArthur, D.W.

    1997-09-02

    An electrostatic alpha radiation detector for measuring alpha radiation emitted from inside an enclosure comprising an electrically conductive expandable electrode for insertion into the enclosure is disclosed. After insertion, the electrically conductive expandable electrode is insulated from the enclosure and defines a decay cavity between the electrically conductive expandable electrode and the enclosure so that air ions generated in the decay cavity are electrostatically captured by the electrically conductive expandable electrode and the enclosure when an electric potential is applied between the electrically conductive expandable electrode and the enclosure. Indicator means are attached to the electrically conductive expandable electrode for indicating an electrical current produced by generation of the air ions generated in the decay cavity by collisions between air molecules and the alpha particles emitted from the enclosure. A voltage source is connected between the indicator means and the electrically conductive enclosure for creating an electric field between the electrically conductive expandable electrode and the enclosure. 4 figs.

  10. Apparatus for detecting alpha radiation in difficult access areas

    DOEpatents

    Steadman, Peter; MacArthur, Duncan W.

    1997-09-02

    An electrostatic alpha radiation detector for measuring alpha radiation emitted from inside an enclosure comprising an electrically conductive expandable electrode for insertion into the enclosure. After insertion, the electrically conductive expandable electrode is insulated from the enclosure and defines a decay cavity between the electrically conductive expandable electrode and the enclosure so that air ions generated in the decay cavity are electrostatically captured by the electrically conductive expandable electrode and the enclosure when an electric potential is applied between the electrically conductive expandable electrode and the enclosure. Indicator means are attached to the electrically conductive expandable electrode for indicating an electrical current produced by generation of the air ions generated in the decay cavity by collisions between air molecules and the alpha particles emitted from the enclosure. A voltage source is connected between the indicator means and the electrically conductive enclosure for creating an electric field between the electrically conductive expandable electrode and the enclosure.

  11. Plant alpha-amylase inhibitors and their interaction with insect alpha-amylases.

    PubMed

    Franco, Octávio L; Rigden, Daniel J; Melo, Francislete R; Grossi-De-Sá, Maria F

    2002-01-01

    Insect pests and pathogens (fungi, bacteria and viruses) are responsible for severe crop losses. Insects feed directly on the plant tissues, while the pathogens lead to damage or death of the plant. Plants have evolved a certain degree of resistance through the production of defence compounds, which may be aproteic, e.g. antibiotics, alkaloids, terpenes, cyanogenic glucosides or proteic, e.g. chitinases, beta-1,3-glucanases, lectins, arcelins, vicilins, systemins and enzyme inhibitors. The enzyme inhibitors impede digestion through their action on insect gut digestive alpha-amylases and proteinases, which play a key role in the digestion of plant starch and proteins. The natural defences of crop plants may be improved through the use of transgenic technology. Current research in the area focuses particularly on weevils as these are highly dependent on starch for their energy supply. Six different alpha-amylase inhibitor classes, lectin-like, knottin-like, cereal-type, Kunitz-like, gamma-purothionin-like and thaumatin-like could be used in pest control. These classes of inhibitors show remarkable structural variety leading to different modes of inhibition and different specificity profiles against diverse alpha-amylases. Specificity of inhibition is an important issue as the introduced inhibitor must not adversely affect the plant's own alpha-amylases, nor the nutritional value of the crop. Of particular interest are some bifunctional inhibitors with additional favourable properties, such as proteinase inhibitory activity or chitinase activity. The area has benefited from the recent determination of many structures of alpha-amylases, inhibitors and complexes. These structures highlight the remarkable variety in structural modes of alpha-amylase inhibition. The continuing discovery of new classes of alpha-amylase inhibitor ensures that exciting discoveries remain to be made. In this review, we summarize existing knowledge of insect alpha-amylases, plant alpha

  12. Linear kinematic air bearing

    NASA Technical Reports Server (NTRS)

    Mayall, S. D.

    1974-01-01

    Bearing provides continuous, smooth movement of the cat's-eye mirror, eliminating wear and deterioration of bearing surface and resulting oscillation effects in servo system. Design features self-aligning configuration; single-point, pivotal pad mounting, having air passage through it; and design of pads that allows for precise control of discharge path of air from pads.

  13. Air Pollution

    MedlinePlus

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

  14. ALPHA MIS: Reference manual

    SciTech Connect

    Lovin, J.K.; Haese, R.L.; Heatherly, R.D.; Hughes, S.E.; Ishee, J.S.; Pratt, S.M.; Smith, D.W.

    1992-02-01

    ALPHA is a powerful and versatile management information system (MIS) initiated and sponsored and by the Finance and Business Management Division of Oak Ridge National Laboratory, who maintain and develop it in concert with the Business Systems Division for its Information Center. A general-purpose MIS, ALPHA allows users to access System 1022 and System 1032 databases to obtain and manage information. From a personal computer or a data terminal, Energy Systems employees can use ALPHA to control their own report reprocessing. Using four general commands (Database, Select, Sort, and Report) they can (1) choose a mainframe database, (2) define subsets within it, (3) sequentially order a subset by one or more variables, and (4) generate a report with their own or a canned format.

  15. Portable alpha spectrometer.

    PubMed

    Martín Sánchez, A; de la Torre Pérez, J

    2012-09-01

    Many portable devices have been designed to detect γ-rays or alpha and beta particles. Most of the α-particle detectors give the total count as a result, without identifying the radionuclides existing in the sample. The development of a device allowing rapid and straightforward α-particle spectrometry would be very useful for detecting the radioactive contents of unknown samples. This work describes the construction of a portable device using silicon semiconductor detectors designed to rapidly detect and possibly identify alpha-emitting radionuclides.

  16. The Apollo Alpha Spectrometer.

    NASA Technical Reports Server (NTRS)

    Jagoda, N.; Kubierschky, K.; Frank, R.; Carroll, J.

    1973-01-01

    Located in the Science Instrument Module of Apollo 15 and 16, the Alpha Particle Spectrometer was designed to detect and measure the energy of alpha particles emitted by the radon isotopes and their daughter products. The spectrometer sensor consisted of an array of totally depleted silicon surface barrier detectors. Biased amplifier and linear gate techniques were utilized to reduce resolution degradation, thereby permitting the use of a single 512 channel PHA. Sensor identification and in-flight radioactive calibration were incorporated to enhance data reduction.

  17. 40 CFR 52.1929 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.1929 Section 52.1929 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) Regulation for preventing significant deterioration of air... preventing significant deterioration of air quality....

  18. Design objectives - Air transportation

    NASA Technical Reports Server (NTRS)

    Beheim, M. A.

    1974-01-01

    The mainline of air transportation is expected to continue to be based on the medium to long haul turbine powered subsonic aircraft. With greater emphasis on energy conservation, there will be considerable interest in making additional progress in propulsion system efficiency. Continued improvement in turbofan engines is expected to occur, but there may be a less conventional approach in the background. Opportunities for expanding short haul air services will certainly materialize. The outlook for supersonic air transport is less clear because of complex political and economic factors.

  19. Technological change and productivity growth in the air transport industry

    NASA Technical Reports Server (NTRS)

    Rosenberg, N.; Thompson, A.; Belsley, S. E.

    1978-01-01

    The progress of the civil air transport industry in the United States was examined in the light of a proposal of Enos who, after examining the growth of the petroleum industry, divided that phenomenon into two phases, the alpha and the beta; that is, the invention, first development and production, and the improvement phase. The civil air transport industry developed along similar lines with the technological progress coming in waves; each wave encompassing several new technological advances while retaining the best of the old ones. At the same time the productivity of the transport aircraft as expressed by the product of the aircraft velocity and the passenger capacity increased sufficiently to allow the direct operating cost in cents per passenger mile to continually decrease with each successive aircraft development.

  20. [alpha]-Oxocarboxylic Acids

    ERIC Educational Resources Information Center

    Kerber, Robert C.; Fernando, Marian S.

    2010-01-01

    Several [alpha]-oxocarboxylic acids play key roles in metabolism in plants and animals. However, there are inconsistencies between the structures as commonly portrayed and the reported acid ionization constants, which result because the acids are predominantly hydrated in aqueous solution; that is, the predominant form is RC(OH)[subscript 2]COOH…

  1. From Alpha to Omega

    ERIC Educational Resources Information Center

    Czaja, Paul Clement

    2006-01-01

    The Alpha point of the authors' life as a Montessori educator began in 1959, when he was a graduate student studying philosophy at Fordham University in the Bronx, New York. While studying the works of the great American philosopher William James, the author came across the writings of Maria Montessori and immediately became captivated by her…

  2. 40 CFR 63.11955 - What are my initial and continuous compliance requirements for other emission sources?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air... gallons, whichever is larger, at standard temperature and pressure. (b) Before opening a...

  3. 40 CFR 63.11955 - What are my initial and continuous compliance requirements for other emission sources?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air... gallons, whichever is larger, at standard temperature and pressure. (b) Before opening a...

  4. 40 CFR 63.11955 - What are my initial and continuous compliance requirements for other emission sources?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air... gallons, whichever is larger, at standard temperature and pressure. (b) Before opening a...

  5. Comparative study regarding the association of alpha 2U globulin with the nephrotoxic mechanism of certain petroleum-based air force fuels. Final report, 1 July 1990-31 August 1993

    SciTech Connect

    Eurell, T.E.

    1993-08-31

    Adult male rats have a strain, dose, and time-dependent renal proximal tubular degeneration induced by certain hydrocarbon compounds. We used rat strain variation (Fisher 344 and NCI Black Reiter) and different hydrocarbon compounds (JP-4, JP-8, decalin and trimethylpentane) to investigate the hydrocarbon-induced nephrotoxic response. Histochemical and morphometric evaluation of NCI-Black Reiter rats exposed to decalin and JP-8 indicated that this strain undergoes an intermediate form of the hydrocarbon-induced nephrotoxicity when compared to the albino Fisher 344 strain. The intermediate nephrotoxic response of the NCI-Black Reiter rat was characterized by approximately a two-fold increase in the number of acid phosphatase reactive lysosomes in renal tubular cells. The NBR rats did not demonstrate an increase in the size of the individual lysosomes, however, a characteristic lysosomal aggregation pattern occurred in renal tubular cells following hydrocarbon exposure. Light and electron microscopic immunohistochemistry revealed increased levels of A2U reactive sites in the renal tubular cell of F344 male rats exposed to decalin, trimethylpentane, JP-4 and JP-8. The nephrotoxic effect of decalin, trimethylpentane, JP-4 and JP-8 appeared to be equivalent as judged by renal tubular lysosomal alterations and increased A2U immunoreactive sites. Most lysosomal proteins in either control or treated animals were not reactive with specific antibodies against A2U. The relative number of A2U reactive sites per unit area did riot increase as lysosomes enlarged or became angular in response to hydrocarbon exposure. Alpha 2U globulin, Hyaline droplet nephropathy, Rats, Petroleum fuels, JP-4, JP-8, Cytoskeleton, Immunohistochemistry.

  6. Summary of Alpha Particle Transport

    SciTech Connect

    Medley, S.S.; White, R.B.; Zweben, S.J.

    1998-08-19

    This paper summarizes the talks on alpha particle transport which were presented at the 5th International Atomic Energy Agency's Technical Committee Meeting on "Alpha Particles in Fusion Research" held at the Joint European Torus, England in September 1997.

  7. 29 CFR 1915.1004 - alpha-Naphthylamine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false alpha-Naphthylamine. 1915.1004 Section 1915.1004 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Toxic and Hazardous...

  8. 29 CFR 1915.1004 - alpha-Naphthylamine.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false alpha-Naphthylamine. 1915.1004 Section 1915.1004 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Toxic and Hazardous...

  9. 29 CFR 1926.1104 - alpha-Naphthylamine.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false alpha-Naphthylamine. 1926.1104 Section 1926.1104 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Toxic and Hazardous Substances § 1926.1104...

  10. 29 CFR 1926.1104 - alpha-Naphthylamine.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false alpha-Naphthylamine. 1926.1104 Section 1926.1104 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Toxic and Hazardous Substances § 1926.1104...

  11. 29 CFR 1926.1104 - alpha-Naphthylamine.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false alpha-Naphthylamine. 1926.1104 Section 1926.1104 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Toxic and Hazardous Substances § 1926.1104...

  12. 29 CFR 1926.1104 - alpha-Naphthylamine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false alpha-Naphthylamine. 1926.1104 Section 1926.1104 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Toxic and Hazardous Substances § 1926.1104...

  13. 29 CFR 1926.1104 - alpha-Naphthylamine.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false alpha-Naphthylamine. 1926.1104 Section 1926.1104 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Toxic and Hazardous Substances § 1926.1104...

  14. AlphaSpectrum ASPECT analysis code for background correction & peak integration

    2005-04-13

    The ASPECT code provides a means for rapid analysis of energy-resolved spectra obtained by multi-channel pulse-height analysis (MCA) during (or after) counting of alpha-emissions from a filter air sample (or other suitably prepared sample) utilizing a solid-state detector, or other detector having sufficient energy resolution indiviual radioisotope peaks indentified in a spectrum are fitted using a peak shape algorithm by non-linear least-square fitting procedures that minimize Chi-square differences between the data and a fitted peakmore » function. The code accomplishes the identification of all significant peaks present in the spectrum with automatic recalibration to the 7.68 Po-214 alpha peak from the Radon-222 decay chain, the subtraction of all radon progeny interference overlaps with lower energy peaks in the energy range of Pu-238, Am-241, Pu-239, and U-234/Th-232, and the integration of the counts in any peak identified for these transuranic radionuclides. The output is therefore in the form of isotope specific net transuranic CPM, DPM or concentration, available in near real-time during air sampling. In this "copyright" version, the assumption is made that the alpha spectra to be analyzed have been stored by unique name in sequential form: "FileName(i)", where "FileName" can be any name and i is the index number of the file saved (e.g., i = 1,2, ..., n). this format is one automatically generated by the alpha Environmental Continuous Air Monitor (ECAM), developed by Los Alamos National Laboratory, and manufactured by Canberra Industries, a Laboratory Industrial Partner for this technology. It is assumed in this version of the code that the alpha spectrum data are stored in a 256 channel spectrum, although a larger num ber of channels could be easily accommodated by small code changes. The ECAM data output format is RADNET compliant (an inidustry standard developed at Los Alamos), and include, in addition to a 256-channel alpha spectrum, data on the

  15. {alpha}-Decay half-lives, {alpha}-capture, and {alpha}-nucleus potential

    SciTech Connect

    Denisov, V. Yu. Khudenko, A.A.

    2009-11-15

    {alpha}-Decay half-lives and {alpha}-capture cross sections are evaluated in the framework of a unified model for {alpha}-decay and {alpha}-capture. In this model {alpha}-decay and {alpha}-capture are considered as penetration of the {alpha}-particle through the potential barrier formed by the nuclear, Coulomb, and centrifugal interactions between the {alpha}-particle and nucleus. The spins and parities of the parent and daughter nuclei as well as the quadrupole and hexadecapole deformations of the daughter nuclei are taken into account for evaluation of the {alpha}-decay half-lives. The {alpha}-decay half-lives for 344 nuclei and the {alpha}-capture cross sections of {sup 40}Ca, {sup 44}Ca, {sup 59}Co, {sup 208}Pb, and {sup 209}Bi agree well with the experimental data. The evaluated {alpha}-decay half-lives within the range of 10{sup -9}{<=}T{sub 1/2}{<=}10{sup 38} s for 1246 {alpha}-emitters are tabulated.

  16. [Pollution of room air].

    PubMed

    Schlatter, J

    1986-01-01

    In the last decade the significance of indoor air pollution to human health has increased because of improved thermal insulation of buildings to save energy: air turnover is reduced and air quality is impaired. The most frequent air pollutants are tobacco smoke, radioactive radon gas emanating from the soil, formaldehyde from furniture and insulation material, nitrogen oxides from gas stoves, as well as solvents from cleaning agents. The most important pollutants leading to health hazards are tobacco smoke and air pollutants which are emitted continuously from building materials and furniture. Such pollutants have to be eliminated by reducing the emission rate. A fresh air supply is necessary to reduce the pollutants resulting from the inhabitants and their activities, the amount depending on the number of inhabitants and the usage of the room. The carbon dioxide level should not exceed 1500 ppm.

  17. 6. INTERIOR OF THE MAIN EQUIPMENT ROOM, AN/FPS66 ALPHA, BUILDING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. INTERIOR OF THE MAIN EQUIPMENT ROOM, AN/FPS66 ALPHA, BUILDING 408, LOOKING WEST. - Mill Valley Air Force Station, Operations Building & Annex, East Ridgecrest Boulevard, Mount Tamalpais, Mill Valley, Marin County, CA

  18. Simultaneous quantification of GABAergic 3alpha,5alpha/3alpha,5beta neuroactive steroids in human and rat serum.

    PubMed

    Porcu, Patrizia; O'Buckley, Todd K; Alward, Sarah E; Marx, Christine E; Shampine, Lawrence J; Girdler, Susan S; Morrow, A Leslie

    2009-01-01

    The 3alpha,5alpha- and 3alpha,5beta-reduced derivatives of progesterone, deoxycorticosterone, dehydroepiandrosterone and testosterone enhance GABAergic neurotransmission and produce inhibitory neurobehavioral and anti-inflammatory effects. Despite substantial information on the progesterone derivative (3alpha,5alpha)-3-hydroxypregnan-20-one (3alpha,5alpha-THP, allopregnanolone), the physiological significance of the other endogenous GABAergic neuroactive steroids has remained elusive. Here, we describe the validation of a method using gas chromatography-mass spectrometry to simultaneously identify serum levels of the eight 3alpha,5alpha- and 3alpha,5beta-reduced derivatives of progesterone, deoxycorticosterone, dehydroepiandrosterone and testosterone. The method shows specificity, sensitivity and enhanced throughput compared to other methods already available for neuroactive steroid quantification. Administration of pregnenolone to rats and progesterone to women produced selective effects on the 3alpha,5alpha- and 3alpha,5beta-reduced neuroactive steroids, indicating differential regulation of their biosynthetic pathways. Pregnenolone administration increased serum levels of 3alpha,5alpha-THP (+1488%, p<0.001), (3alpha,5alpha)-3,21-dihydroxypregnan-20-one (3alpha,5alpha-THDOC, +205%, p<0.01), (3alpha,5alpha)-3-hydroxyandrostan-17-one (3alpha,5alpha-A, +216%, p<0.001), (3alpha,5alpha,17beta)-androstane-3,17-diol (3alpha,5alpha-A-diol, +190%, p<0.01). (3alpha,5beta)-3-hydroxypregnan-20-one (3alpha,5beta-THP) and (3alpha,5beta)-3-hydroxyandrostan-17-one (3alpha,5beta-A) were not altered, while (3alpha,5beta)-3,21-dihydroxypregnan-20-one (3alpha,5beta-THDOC) and (3alpha,5beta,17beta)-androstane-3,17-diol (3alpha,5beta-A-diol) were increased from undetectable levels to 271+/-100 and 2.4+/-0.9 pg+/-SEM, respectively (5/8 rats). Progesterone administration increased serum levels of 3alpha,5alpha-THP (+1806%, p<0.0001), 3alpha,5beta-THP (+575%, p<0.001), 3alpha,5alpha

  19. Alpha contamination assessment for D&D activities: Technology overview

    SciTech Connect

    Conaway, J.G.; Rawool-Sullivan, M.W.; MacArthur, D.W.

    1996-02-01

    Instruments based on the principle of Long-Range Alpha Detection (LRAD) detect the ions created in ambient air by Ionizing radiation, particularly alpha radiation, interacting with air molecules. Using either an electrostatic field or forced convection, these ions can be transported to a detection grid where the ions produce a small current that is measured with a sensitive electrometer. LRAD-based instruments can give separate, simultaneous measurements of alpha-emitting solids and inert radioactive gases such as radon. LRAD-based instruments assess surface contamination on an entire object or large surface area in a single, rapid measurement, including relatively inaccessible areas such as interior surfaces of pipes and process equipment. The LRAD concept is well proven and has been developed into a range of different radiation detection devices. This paper presents an overview of the technology, while several associated papers explore specific applications in greater detail.

  20. Air Abrasion

    MedlinePlus

    ... 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 ...

  1. Air cell

    NASA Astrophysics Data System (ADS)

    Okamura, Okiyoshi; Wakasa, Masayuki; Tamanoi, Yoshihito

    1991-04-01

    The present invention relates to an air cell. This air cell provides a compact light-weight power source for model aircraft permitting them to fly for an extended period so that they may be used for such practical purposes as crop dusting, surveying, and photographing. The cell is comprised of a current collector so disposed between a magnesium, zinc, or aluminum alloy cathode and a petroleum graphite anode that it is in contact with the anode. The anode is formed by adding polytetrafluoroethylene dispersion liquid in a mixture of active carbon and graphite powder, pouring the mixture into a mold and heating it to form the anode. It is fabricated by a plurality of anode sections and is formed with at least one hole so that it can provide a cell which is compact in size and light in weight yet is capable of generating a high output. The anode, the cathode, and a separator are wetted by an electrolytic liquid. The electrolyte is continuously supplied through the life of the cell.

  2. Pulse radiolytic study of alpha-tocopherol radical mechanisms in ethanolic solution

    SciTech Connect

    Jore, D.; Patterson, L.K.; Ferradini, C.

    1986-01-01

    Pulse radiolytic studies of alpha-tocopherol (alpha TH) oxidation-reduction processes were carried out with low doses (5 Gy) of high-energy electrons in O/sub 2/-, N/sub 2/-, and air-saturated ethanolic solutions. Depending on the concentration of oxygen in solution, two different radicals, A . and B ., were observed. The first, A ., was obtained under N/sub 2/ and results from alpha TH reaction with solvated electron (k alpha TH + e-solv = 3.4 X 10(8) mol-1 liter s-1) and with H/sub 3/C-CH-OH, (R.) (k alpha TH + R. = 5 X 10(5) mol-1 liter s-1). B., observed under O/sub 2/, is produced by alpha TH reaction with RO/sub 2/ . peroxyl radicals (k alpha TH + RO/sub 2/ . = 9.5 X 10(4) mol-1 liter s-1).

  3. Continuous and passive environmental radon monitoring: Measuring methods and health effects. (Latest citations from the INSPEC database). Published Search

    SciTech Connect

    1996-05-01

    The bibliography contains citations concerning continuous and passive radon (Rn) monitoring, measurement methods and equipment, and health effects from Rn concentration in air, water, and soils. Citations discuss the design, development, and evaluation of monitoring and detection devices, including alpha spectroscopy and dosimetry, track detecting and scintillation, thermoluminescent, electret, and electrode collection. Sources of Rn concentration levels found in building materials, ventilation systems, soils, and ground water are examined. Lung cancer-associated risks from Rn radiation exposure are explored. Radon monitoring in mining operations is excluded. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  4. 40 CFR 81.145 - State Capital Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air... City, Chesterfield, Dinwiddie, Goochland, Greensville, Hanover, Henrico, New Kent, Powhatan,...

  5. 40 CFR 81.145 - State Capital Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air... City, Chesterfield, Dinwiddie, Goochland, Greensville, Hanover, Henrico, New Kent, Powhatan,...

  6. 40 CFR 81.145 - State Capital Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air... City, Chesterfield, Dinwiddie, Goochland, Greensville, Hanover, Henrico, New Kent, Powhatan,...

  7. 40 CFR 81.145 - State Capital Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air... City, Chesterfield, Dinwiddie, Goochland, Greensville, Hanover, Henrico, New Kent, Powhatan,...

  8. 40 CFR 81.78 - Metropolitan Portland Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of...—Cumberland, Sagadahoc, York. Towns—Brownfield, Denmark, Fryeburg, Hiram, Porter....

  9. 40 CFR 81.183 - Eastern Connecticut Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of... within the outermost boundaries of the area so delimited): In the State of Connecticut:...

  10. 40 CFR 81.184 - Northwestern Connecticut Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES...: Towns—Barkhamsted, Canaan, Colebrook, Cornwall, Goshen, Hartland, Harwinton, Kent, Litchfield,...

  11. 40 CFR 81.146 - Valley of Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Harrisonburg, Lexington, Radford, Roanoke, Salem, Staunton, Waynesboro, Winchester....

  12. 40 CFR 81.183 - Eastern Connecticut Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of... within the outermost boundaries of the area so delimited): In the State of Connecticut:...

  13. 40 CFR 81.143 - Central Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Lynchburg, Martinsville, South Boston. Towns—Blackstone, Farmville, Rocky Mount, South Hill....

  14. 40 CFR 81.143 - Central Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Lynchburg, Martinsville, South Boston. Towns—Blackstone, Farmville, Rocky Mount, South Hill....

  15. 40 CFR 81.237 - Northeast Georgia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Newton County, Oconee County, Oglethorpe County, Rabun County, Stephens County, Towns County,...

  16. 40 CFR 81.237 - Northeast Georgia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Newton County, Oconee County, Oglethorpe County, Rabun County, Stephens County, Towns County,...

  17. 40 CFR 81.184 - Northwestern Connecticut Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES...: Towns—Barkhamsted, Canaan, Colebrook, Cornwall, Goshen, Hartland, Harwinton, Kent, Litchfield,...

  18. 40 CFR 81.184 - Northwestern Connecticut Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES...: Towns—Barkhamsted, Canaan, Colebrook, Cornwall, Goshen, Hartland, Harwinton, Kent, Litchfield,...

  19. 40 CFR 81.183 - Eastern Connecticut Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of... within the outermost boundaries of the area so delimited): In the State of Connecticut:...

  20. 40 CFR 81.237 - Northeast Georgia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Newton County, Oconee County, Oglethorpe County, Rabun County, Stephens County, Towns County,...

  1. 40 CFR 81.143 - Central Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Lynchburg, Martinsville, South Boston. Towns—Blackstone, Farmville, Rocky Mount, South Hill....

  2. 40 CFR 81.78 - Metropolitan Portland Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of...—Cumberland, Sagadahoc, York. Towns—Brownfield, Denmark, Fryeburg, Hiram, Porter....

  3. 40 CFR 81.146 - Valley of Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Harrisonburg, Lexington, Radford, Roanoke, Salem, Staunton, Waynesboro, Winchester....

  4. 40 CFR 81.143 - Central Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Lynchburg, Martinsville, South Boston. Towns—Blackstone, Farmville, Rocky Mount, South Hill....

  5. 40 CFR 81.143 - Central Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Lynchburg, Martinsville, South Boston. Towns—Blackstone, Farmville, Rocky Mount, South Hill....

  6. 40 CFR 81.184 - Northwestern Connecticut Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES...: Towns—Barkhamsted, Canaan, Colebrook, Cornwall, Goshen, Hartland, Harwinton, Kent, Litchfield,...

  7. 40 CFR 81.146 - Valley of Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Harrisonburg, Lexington, Radford, Roanoke, Salem, Staunton, Waynesboro, Winchester....

  8. 40 CFR 81.237 - Northeast Georgia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Newton County, Oconee County, Oglethorpe County, Rabun County, Stephens County, Towns County,...

  9. 40 CFR 81.146 - Valley of Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Harrisonburg, Lexington, Radford, Roanoke, Salem, Staunton, Waynesboro, Winchester....

  10. 40 CFR 81.183 - Eastern Connecticut Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of... within the outermost boundaries of the area so delimited): In the State of Connecticut:...

  11. 40 CFR 81.78 - Metropolitan Portland Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of...—Cumberland, Sagadahoc, York. Towns—Brownfield, Denmark, Fryeburg, Hiram, Porter....

  12. 40 CFR 81.183 - Eastern Connecticut Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of... within the outermost boundaries of the area so delimited): In the State of Connecticut:...

  13. 40 CFR 81.78 - Metropolitan Portland Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of...—Cumberland, Sagadahoc, York. Towns—Brownfield, Denmark, Fryeburg, Hiram, Porter....

  14. 40 CFR 81.237 - Northeast Georgia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Newton County, Oconee County, Oglethorpe County, Rabun County, Stephens County, Towns County,...

  15. 40 CFR 81.184 - Northwestern Connecticut Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES...: Towns—Barkhamsted, Canaan, Colebrook, Cornwall, Goshen, Hartland, Harwinton, Kent, Litchfield,...

  16. 40 CFR 81.146 - Valley of Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of..., Harrisonburg, Lexington, Radford, Roanoke, Salem, Staunton, Waynesboro, Winchester....

  17. 40 CFR 81.78 - Metropolitan Portland Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of...—Cumberland, Sagadahoc, York. Towns—Brownfield, Denmark, Fryeburg, Hiram, Porter....

  18. 40 CFR 1065.150 - Continuous sampling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Continuous sampling. 1065.150 Section 1065.150 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.150 Continuous sampling. You may use...

  19. 40 CFR 1065.150 - Continuous sampling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Continuous sampling. 1065.150 Section 1065.150 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.150 Continuous sampling. You may use...

  20. 40 CFR 1065.150 - Continuous sampling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Continuous sampling. 1065.150 Section 1065.150 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.150 Continuous sampling. You may use...

  1. 40 CFR 1065.150 - Continuous sampling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Continuous sampling. 1065.150 Section 1065.150 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.150 Continuous sampling. You may use...

  2. 40 CFR 1065.150 - Continuous sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Continuous sampling. 1065.150 Section 1065.150 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.150 Continuous sampling. You may use...

  3. 40 CFR 61.34 - Air sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Air sampling. 61.34 Section 61.34 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.34...

  4. An alpha/beta/gamma health physics instrument with pulse-shape discrimination

    SciTech Connect

    McElhaney, S.A.; Chiles, M.M.; Ramsey, J.A.

    1990-01-01

    A recent breakthrough in alpha scintillation detector design supports the feasibility of extending this new technology to the development of a monolithic alpha/beta/gamma ({alpha}/{beta}/{gamma}) scintillation detector. The new scintillator is physically robust and chemically resistant to environmental conditions encountered in radiation monitoring, and yet inexpensive to manufacture. The use of pulse-shape discrimination electronics allows pulses from each scintillator to be separated for particle identification. An {alpha}/{beta}/{gamma} detector has a wide variety of possible applications including laundry monitoring, wastewater monitoring, air sampling, and health physics instrumentation. 2 refs., 1 fig.

  5. Sequential activation of alpha-actin genes during avian cardiogenesis: vascular smooth muscle alpha-actin gene transcripts mark the onset of cardiomyocyte differentiation

    PubMed Central

    1988-01-01

    The expression of cytoplasmic beta-actin and cardiac, skeletal, and smooth muscle alpha-actins during early avian cardiogenesis was analyzed by in situ hybridization with mRNA-specific single-stranded DNA probes. The cytoplasmic beta-actin gene was ubiquitously expressed in the early chicken embryo. In contrast, the alpha-actin genes were sequentially activated in avian cardiac tissue during the early stages of heart tube formation. The accumulation of large quantities of smooth muscle alpha-actin transcripts in epimyocardial cells preceded the expression of the sarcomeric alpha-actin genes. The accumulation of skeletal alpha-actin mRNAs in the developing heart lagged behind that of cardiac alpha-actin by several embryonic stages. At Hamburger- Hamilton stage 12, the smooth muscle alpha-actin gene was selectively down-regulated in the heart such that only the conus, which subsequently participates in the formation of the vascular trunks, continued to express this gene. This modulation in smooth muscle alpha- actin gene expression correlated with the beginning of coexpression of sarcomeric alpha-actin transcripts in the epimyocardium and the onset of circulation in the embryo. The specific expression of the vascular smooth muscle alpha-actin gene marks the onset of differentiation of cardiac cells and represents the first demonstration of coexpression of both smooth muscle and striated alpha-actin genes within myogenic cells. PMID:3204121

  6. 29 CFR 1202.13 - Air carriers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 4 2013-07-01 2013-07-01 false Air carriers. 1202.13 Section 1202.13 Labor Regulations Relating to Labor (Continued) NATIONAL MEDIATION BOARD RULES OF PROCEDURE § 1202.13 Air carriers. By the... carrier by air engaged in interstate or foreign commerce, and every carrier by air transporting mail...

  7. 29 CFR 1202.13 - Air carriers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 4 2011-07-01 2011-07-01 false Air carriers. 1202.13 Section 1202.13 Labor Regulations Relating to Labor (Continued) NATIONAL MEDIATION BOARD RULES OF PROCEDURE § 1202.13 Air carriers. By the... carrier by air engaged in interstate or foreign commerce, and every carrier by air transporting mail...

  8. 29 CFR 1202.13 - Air carriers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 4 2012-07-01 2012-07-01 false Air carriers. 1202.13 Section 1202.13 Labor Regulations Relating to Labor (Continued) NATIONAL MEDIATION BOARD RULES OF PROCEDURE § 1202.13 Air carriers. By the... carrier by air engaged in interstate or foreign commerce, and every carrier by air transporting mail...

  9. 29 CFR 1202.13 - Air carriers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 4 2014-07-01 2014-07-01 false Air carriers. 1202.13 Section 1202.13 Labor Regulations Relating to Labor (Continued) NATIONAL MEDIATION BOARD RULES OF PROCEDURE § 1202.13 Air carriers. By the... carrier by air engaged in interstate or foreign commerce, and every carrier by air transporting mail...

  10. 29 CFR 1202.13 - Air carriers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false Air carriers. 1202.13 Section 1202.13 Labor Regulations Relating to Labor (Continued) NATIONAL MEDIATION BOARD RULES OF PROCEDURE § 1202.13 Air carriers. By the... carrier by air engaged in interstate or foreign commerce, and every carrier by air transporting mail...

  11. Proteinaceous alpha-amylase inhibitors.

    PubMed

    Svensson, Birte; Fukuda, Kenji; Nielsen, Peter K; Bønsager, Birgit C

    2004-02-12

    Proteins that inhibit alpha-amylases have been isolated from plants and microorganisms. These inhibitors can have natural roles in the control of endogenous alpha-amylase activity or in defence against pathogens and pests; certain inhibitors are reported to be antinutritional factors. The alpha-amylase inhibitors belong to seven different protein structural families, most of which also contain evolutionary related proteins without inhibitory activity. Two families include bifunctional inhibitors acting both on alpha-amylases and proteases. High-resolution structures are available of target alpha-amylases in complex with inhibitors from five families. These structures indicate major diversity but also some similarity in the structural basis of alpha-amylase inhibition. Mutational analysis of the mechanism of inhibition was performed in a few cases and various protein engineering and biotechnological approaches have been outlined for exploitation of the inhibitory function. PMID:14871655

  12. Background canceling surface alpha detector

    DOEpatents

    MacArthur, Duncan W.; Allander, Krag S.; Bounds, John A.

    1996-01-01

    A background canceling long range alpha detector which is capable of providing output proportional to both the alpha radiation emitted from a surface and to radioactive gas emanating from the surface. The detector operates by using an electrical field between first and second signal planes, an enclosure and the surface or substance to be monitored for alpha radiation. The first and second signal planes are maintained at the same voltage with respect to the electrically conductive enclosure, reducing leakage currents. In the presence of alpha radiation and radioactive gas decay, the signal from the first signal plane is proportional to both the surface alpha radiation and to the airborne radioactive gas, while the signal from the second signal plane is proportional only to the airborne radioactive gas. The difference between these two signals is proportional to the surface alpha radiation alone.

  13. Background canceling surface alpha detector

    DOEpatents

    MacArthur, D.W.; Allander, K.S.; Bounds, J.A.

    1996-06-11

    A background canceling long range alpha detector which is capable of providing output proportional to both the alpha radiation emitted from a surface and to radioactive gas emanating from the surface. The detector operates by using an electrical field between first and second signal planes, an enclosure and the surface or substance to be monitored for alpha radiation. The first and second signal planes are maintained at the same voltage with respect to the electrically conductive enclosure, reducing leakage currents. In the presence of alpha radiation and radioactive gas decay, the signal from the first signal plane is proportional to both the surface alpha radiation and to the airborne radioactive gas, while the signal from the second signal plane is proportional only to the airborne radioactive gas. The difference between these two signals is proportional to the surface alpha radiation alone. 5 figs.

  14. Calcification provides mechanical reinforcement to whale baleen alpha-keratin.

    PubMed

    Szewciw, L J; de Kerckhove, D G; Grime, G W; Fudge, D S

    2010-09-01

    Hard alpha-keratins such as hair, nail, wool and horn are stiff epidermal appendages used by mammals in a variety of functions including thermoregulation, feeding and intraspecific competition. Hard alpha-keratins are fibre-reinforced structures consisting of cytoskeletal elements known as 'intermediate filaments' embedded in an amorphous protein matrix. Recent research has shown that intermediate filaments are soft and extensible in living keratinocytes but become far stiffer and less extensible in keratinized cells, and this stiffening may be mediated by air-drying. Baleen, the keratinous plates used by baleen whales during filter feeding, is an unusual mammalian keratin in that it never air dries, and in some species, it represents the most heavily calcified of all the hard alpha-keratins. We therefore tested the hypothesis that whale baleen is stiffened by calcification. Here, we provide, to our knowledge, the first comprehensive description of baleen material properties and show that calcification contributes to overcoming the shortcomings of stiffening this hard alpha-keratin without the benefit of air-drying. We also demonstrate striking interspecies differences in the calcification patterns among three species of baleen whales and provide novel insights into the function and evolution of this unusual biomaterial.

  15. Lorentz violation and {alpha} decay

    SciTech Connect

    Altschul, Brett

    2009-01-01

    Relating the effective Lorentz violation coefficients for composite particles to the coefficients for their constituent fields is a challenging problem. We calculate the Lorentz violation coefficients relevant to the dynamics of an {alpha} particle in terms of proton and neutron coefficients. The {alpha}-particle coefficients would lead to anisotropies in the {alpha} decays of nuclei, and because the decay process involves quantum tunneling, the effects of any Lorentz violations could be exponentially enhanced.

  16. G-protein. alpha. -subunit expression, myristoylation, and membrane association in COS cells

    SciTech Connect

    Mumby, S.M.; Gilman, A.G. ); Heukeroth, R.O.; Gordon, J.I. )

    1990-01-01

    Myristolyation of seven different {alpha} subunits of guanine nucleotide-binding regulatory proteins (G proteins) was examined by expressing these proteins in monkey kidney COS cells. Metabolic labeling studies of cells transfected with cytomegalovirus-based expression vectors indicated that ({sup 3}H)myristate was incorporated into {alpha}{sub i1}, {alpha}{sub i2}, {alpha}{sub i3}, {alpha}{sub 0}, and {alpha}{sub 1}, and {alpha}{sub z} but not {alpha}{sub s} subunits. The role of myristoylation in the association of {alpha} subunits with membranes was analyzed by site-directed mutagenesis and by substitution of myristate with a less hydrophobic analog, 10-(propoxy)decanoate (11-oxamyristate). Myristoylation of {alpha}{sub 0} was blocked when an alanine residue was substituted for its amino-terminal glycine, as was association of the protein with membranes. Substitution of the myristoyl group with 11-oxamyristate affected the cellular distribution of a subset of acylated {alpha} subunits. The results are consistent with a model wherein the hydrophobic interaction of myristate with the bilayer permits continued association of the protein with the plasma membrane when G-protein {alpha} subunits dissociated from {beta}{gamma}.

  17. Modeling Solar Lyman Alpha Irradiance

    NASA Technical Reports Server (NTRS)

    Pap, J.; Hudson, H. S.; Rottman, G. J.; Willson, R. C.; Donnelly, R. F.; London, J.

    1990-01-01

    Solar Lyman alpha irradiance is estimated from various solar indices using linear regression analyses. Models developed with multiple linear regression analysis, including daily values and 81-day running means of solar indices, predict reasonably well both the short- and long-term variations observed in Lyman alpha. It is shown that the full disk equivalent width of the He line at 1083 nm offers the best proxy for Lyman alpha, and that the total irradiance corrected for sunspot effect also has a high correlation with Lyman alpha.

  18. ISS Update: Alpha Magnetic Spectrometer

    NASA Video Gallery

    NASA Public Affairs Officer Kelly Humphries interviews Trent Martin, Johnson Space Center project manager for the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. Questions...

  19. Imaging of alpha emitters in a field environment

    NASA Astrophysics Data System (ADS)

    Sand, Johan; Ihantola, Sakari; Peräjärvi, Kari; Nicholl, Adrian; Hrnecek, Erich; Toivonen, Harri; Toivonen, Juha

    2015-05-01

    Cameras sensitive to ultraviolet light can be applied to detection of surface contamination induced by alpha particle emitters. When absorbed in air, alpha particles excite nitrogen molecules and the radiative relaxation creates a faint light emission. This radioluminescence can be used for detection purposes, provided that background lighting levels are low. In this work, three low-light sensitive camera technologies (CCD, EMCCD and ICCD) were utilized in a nuclear facility, and their performance in detecting alpha emitters was investigated. The results show that low readout noise is essential for the detection of radioluminescence, as it allows short exposure times to be used. The ICCD camera was found to perform slightly better than the EMCCD camera in the field, while both enable the detection of MBq level alpha activities in 100 s in the test configuration (camera-target distance 0.5 m). Overall, the cameras and techniques used in this study are shown to be effective in detecting alpha emitters in a standard glovebox. This technology can be applied to nuclear security, safety and safeguards, when stand-off detection of alpha emitters is required.

  20. Structure and diversity of the TCR alpha-chain in a teleost fish.

    PubMed

    Partula, S; de Guerra, A; Fellah, J S; Charlemagne, J

    1996-07-01

    T cell receptor beta-chain genes are well characterized in representatives of most vertebrate phyla, from sharks to mammals, but the molecular structure of complete TCR alpha-chains has not yet been established in cold-blooded vertebrates. We used a PCR approach to isolate cDNAs encoding putative teleost fish (Oncorhynchus mykiss, rainbow trout) TCR alpha-chains. Eight V alpha segments were identified, belonging to six different families, and the best amino acid sequence identity scores for these trout V alpha were all provided by mammalian V alpha or V delta sequences. Twenty-four (60.1 %) of the 39 analyzed V alpha segments belong to the V alpha 2 family, which has limited homology with mammalian V alpha/delta sequences and with the human V pre-B sequence. A total of 32 different J alpha segments were identified from 40 J alpha regions sequenced, suggesting that a large repertoire of J alpha segments is a characteristic of most vertebrates. The structural properties of the TCR alpha-chain complementarity-determining region 3 loop are well conserved between trout and mammals, suggesting that this region has been under continuous selective pressure in jawed vertebrate evolution. The trout C alpha segment has conserved N-terminal and transmembrane domains, but the C alpha intercysteine distance contains only 40 residues, significantly smaller as compared with mammals (49-56 residues). The conserved features of teleost fish TCR beta- and alpha-chains with their mammalian equivalents suggest that TCR-alpha beta receptors were still present in the common Devonian ancestors of modern teleost fish and mammals, about 450 million years ago. PMID:8683116

  1. CCAAT/enhancer binding protein alpha regulates p21 protein and hepatocyte proliferation in newborn mice.

    PubMed Central

    Timchenko, N A; Harris, T E; Wilde, M; Bilyeu, T A; Burgess-Beusse, B L; Finegold, M J; Darlington, G J

    1997-01-01

    CCAAT/enhancer binding protein alpha (C/EBP alpha) is expressed at high levels in quiescent hepatocytes and in differentiated adipocytes. In cultured cells, C/EBP alpha inhibits cell proliferation in part via stabilization of the p21 protein. The role of C/EBP alpha in regulating hepatocyte proliferation in vivo is presented herein. In C/EBP alpha knockout newborn mice, p21 protein levels are reduced in the liver, and the fraction of hepatocytes synthesizing DNA is increased. Greater than 30% of the hepatocytes in C/EBP alpha knockout animals continue to proliferate at day 17 of postnatal life when cell division in wild-type littermates is low (3%). p21 protein levels are relatively high in wild-type neonates but undetectable in C/EBP alpha knockout mice. The reduction of p21 protein in the highly proliferating livers that lack C/EBP alpha suggests that p21 is responsible for C/EBP alpha-mediated control of liver proliferation in newborn mice. During rat liver regeneration, the amounts of both C/EBP alpha and p21 proteins are decreased before DNA synthesis (6 to 12 h) and then return to presurgery levels at 48 h. Although C/EBP alpha controls p21 protein levels, p21 mRNA is not influenced by C/EBP alpha in liver. Using coimmunoprecipitation and a mammalian two-hybrid assay system, we have shown the interaction of C/EBP alpha and p21 proteins. Study of p21 stability in liver nuclear extracts showed that C/EBP alpha blocks proteolytic degradation of p21. Our data demonstrate that C/EBP alpha regulates hepatocyte proliferation in newborn mice and that in liver, the level of p21 protein is under posttranscriptional control, consistent with the hypothesis that protein-protein interaction with C/EBP alpha determines p21 levels. PMID:9372966

  2. Resting alpha activity predicts learning ability in alpha neurofeedback

    PubMed Central

    Wan, Feng; Nan, Wenya; Vai, Mang I.; Rosa, Agostinho

    2014-01-01

    Individuals differ in their ability to learn how to regulate the brain activity by neurofeedback. This study aimed to investigate whether the resting alpha activity can predict the learning ability in alpha neurofeedback. A total of 25 subjects performed 20 sessions of individualized alpha neurofeedback and the learning ability was assessed by three indices respectively: the training parameter changes between two periods, within a short period and across the whole training time. It was found that the resting alpha amplitude measured before training had significant positive correlations with all learning indices and could be used as a predictor for the learning ability prediction. This finding would help the researchers in not only predicting the training efficacy in individuals but also gaining further insight into the mechanisms of alpha neurofeedback. PMID:25071528

  3. Air resources

    SciTech Connect

    1995-10-01

    This section describes the ambient (surrounding) air quality of the TVA region, discusses TVA emission contributions to ambient air quality, and identifies air quality impacts to human health and welfare. Volume 2 Technical Document 2, Environmental Consequences, describes how changes in TVA emissions could affect regional air quality, human health, environmental resources, and materials. The primary region of the affected environment is broadly defined as the state of Tennessee, as well as southern Kentucky, western Virginia, southern West Virginia, western North Carolina, and northern Georgia, Alabama, and Mississippi. This area represents the watershed of the Tennessee River and the 201 counties of the greater TVA service area. Emissions from outside the Tennessee Valley region contribute to air quality in the Valley. Also, TVA emissions are transported outside the Valley and have some impact on air quality beyond the primary study area. Although the study area experiences a number of air quality problems, overall air quality is good.

  4. Microscopic cluster model of {alpha}+n, {alpha}+p, {alpha}+ {sup 3}He, and {alpha}+{alpha} elastic scattering from a realistic effective nuclear interaction

    SciTech Connect

    Dohet-Eraly, J.; Baye, D.

    2011-07-15

    An effective nucleon-nucleon interaction adapted to cluster-model calculations of collisions is derived from the realistic Argonne potential AV18 with the unitary correlation operator method. The unitary correlation is determined from the {alpha}+{alpha} elastic phase shifts calculated in a cluster approach by the generator coordinate method coupled with the microscopic R-matrix method. With this interaction, the elastic phase shifts for the {alpha}+n, {alpha}+p, and {alpha}+{sup 3}He collisions are calculated within the same model. Without further adjustment, a good agreement with experimental data is obtained with a small model space.

  5. Continuous home oxygen therapy.

    PubMed

    Ortega Ruiz, Francisco; Díaz Lobato, Salvador; Galdiz Iturri, Juan Bautista; García Rio, Francisco; Güell Rous, Rosa; Morante Velez, Fátima; Puente Maestu, Luis; Tàrrega Camarasa, Julia

    2014-05-01

    Oxygen therapy is defined as the therapeutic use of oxygen and consists of administering oxygen at higher concentrations than those found in room air, with the aim of treating or preventing hypoxia. This therapeutic intervention has been shown to increase survival in patients with chronic obstructive pulmonary disease (COPD) and respiratory failure. Although this concept has been extended by analogy to chronic respiratory failure caused by respiratory and non-respiratory diseases, continuous oxygen therapy has not been shown to be effective in other disorders. Oxygen therapy has not been shown to improve survival in patients with COPD and moderate hypoxaemia, nor is there consensus regarding its use during nocturnal desaturations in COPD or desaturations caused by effort. The choice of the oxygen source must be made on the basis of criteria such as technical issues, patient comfort and adaptability and cost. Flow must be adjusted to achieve appropriate transcutaneous oxyhaemoglobin saturation correction.

  6. Air Pollution.

    ERIC Educational Resources Information Center

    Gilpin, Alan

    A summary of one of our most pressing environmental problems, air pollution, is offered in this book by the Director of Air Pollution Control for the Queensland (Australia) State Government. Discussion of the subject is not restricted to Queensland or Australian problems and policies, however, but includes analysis of air pollution the world over.…

  7. Alpha particle emitters in medicine

    SciTech Connect

    Fisher, D.R.

    1989-09-01

    Radiation-induced cancer of bone, liver and lung has been a prominent harmful side-effect of medical applications of alpha emitters. In recent years, however, the potential use of antibodies labeled with alpha emitting radionuclides against cancer has seemed promising because alpha particles are highly effective in cell killing. High dose rates at high LET, effectiveness under hypoxic conditions, and minimal expectancy of repair are additional advantages of alpha emitters over antibodies labeled with beta emitting radionuclides for cancer therapy. Cyclotron-produced astatine-211 ({sup 211}At) and natural bismuth-212 ({sup 212}Bi) have been proposed and are under extensive study in the United States and Europe. Radium-223 ({sup 223}Ra) also has favorable properties as a potential alpha emitting label, including a short-lived daughter chain with four alpha emissions. The radiation dosimetry of internal alpha emitters is complex due to nonuniformly distributed sources, short particle tracks, and high relative specific ionization. The variations in dose at the cellular level may be extreme. Alpha-particle radiation dosimetry, therefore, must involve analysis of statistical energy deposition probabilities for cellular level targets. It must also account fully for nonuniform distributions of sources in tissues, source-target geometries, and particle-track physics. 18 refs., 4 figs.

  8. Air Force seal activities

    NASA Astrophysics Data System (ADS)

    Mayhew, Ellen R.

    1994-07-01

    Seal technology development is an important part of the Air Force's participation in the Integrated High Performance Turbine Engine Technology (IHPTET) initiative, the joint DOD, NASA, ARPA, and industry endeavor to double turbine engine capabilities by the turn of the century. Significant performance and efficiency improvements can be obtained through reducing internal flow system leakage, but seal environment requirements continue to become more extreme as the engine thermodynamic cycles advance towards these IHPTET goals. Brush seal technology continues to be pursued by the Air Force to reduce leakage at the required conditions. Likewise, challenges in engine mainshaft air/oil seals are also being addressed. Counter-rotating intershaft applications within the IHPTET initiative involve very high rubbing velocities. This viewgraph presentation briefly describes past and current seal research and development programs and gives a summary of seal applications in demonstrator and developmental engine testing.

  9. Alpha detection in pipes using an inverting membrane scintillator

    SciTech Connect

    Kendrick, D.T.; Cremer, C.D.; Lowry, W.

    1995-10-01

    Characterization of surface alpha emitting contamination inside enclosed spaces such as piping systems presents an interesting radiological measurement challenge. Detection of these alpha particles from the exterior of the pipe is impossible since the alpha particles are completely absorbed by the pipe wall. Traditional survey techniques, using hand-held instruments, simply can not be used effectively inside pipes. Science and Engineering Associates, Inc. is currently developing an enhancement to its Pipe Explorer{trademark} system that will address this challenge. The Pipe Explorer{trademark} uses a unique sensor deployment method where an inverted tubular membrane is propagated through complex pipe runs via air pressure. The inversion process causes the membrane to fold out against the pipe wall, such that no part of the membrane drags along the pipe wall. This deployment methodology has been successfully demonstrated at several DOE sites to transport specially designed beta and gamma, scintillation detectors into pipes ranging in length up to 250 ft.

  10. Prevalence of -alpha(3.7) and alpha alpha alpha(anti3.7) alleles in sickle cell trait and beta-thalassemia patients in Mexico.

    PubMed

    Nava, María Paulina; Ibarra, Bertha; Magaña, María Teresa; de la Luz Chávez, María; Perea, F Javier

    2006-01-01

    The aim of this study was to determine the frequency of alpha-globin gene mutations in three groups of Mexican unrelated individuals. The first two groups were normal and sickle cell trait individuals from the Costa Chica region, a place with a 12.8% frequency of HbS carriers, and the third group comprised of Mexican mestizo patients with beta-thalassemia. We searched for -alpha(3.7) and -alpha(4.2) alpha(+)-thalassemia deletion alleles, as well as the alpha alpha alpha(anti3.7) triplication through long-gap PCR. The alleles -alpha(3.7) and alpha alpha alpha(anti3.7) were found in the heterozygote state only; 19% of the normal subjects had the -alpha(3.7) allele, and 2% showed the alpha alpha alpha(anti3.7) allele. In individuals with the sickle cell trait, 17% had the -alpha(3.7) deletion, and the alpha alpha alpha(anti3.7) triplication was observed in 3% of these individuals. We revealed that 16% of the subjects with beta-thalassemia showed the -alpha(3.7) deletion and 28% the alpha alpha alpha(anti3.7) triplication. The -alpha(4.2) deletion was not detected in any individual. The frequency of the -alpha(3.7) allele was roughly the same in the three groups studied; this can be explained by the fact that the three groups have common genes from Africa and the Mediterranean, where a high prevalence of alpha(+)-thalassemia has been observed. To our knowledge, the frequency of alpha alpha alpha(anti3.7) triplication observed in the Mexican beta-thalassemia patients is the highest reported. As the -alpha(3.7) and alpha alpha alpha(anti3.7) alleles are very common in our selected populations, we believe that there is a need to investigate systematically the alpha-globin gene mutations in all hemoglobinopathies in the Mexican population.

  11. Process air quality data

    NASA Technical Reports Server (NTRS)

    Butler, C. M.; Hogge, J. E.

    1978-01-01

    Air quality sampling was conducted. Data for air quality parameters, recorded on written forms, punched cards or magnetic tape, are available for 1972 through 1975. Computer software was developed to (1) calculate several daily statistical measures of location, (2) plot time histories of data or the calculated daily statistics, (3) calculate simple correlation coefficients, and (4) plot scatter diagrams. Computer software was developed for processing air quality data to include time series analysis and goodness of fit tests. Computer software was developed to (1) calculate a larger number of daily statistical measures of location, and a number of daily monthly and yearly measures of location, dispersion, skewness and kurtosis, (2) decompose the extended time series model and (3) perform some goodness of fit tests. The computer program is described, documented and illustrated by examples. Recommendations are made for continuation of the development of research on processing air quality data.

  12. Air conditioning system

    DOEpatents

    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.

  13. Air bag restraint device

    DOEpatents

    Marts, Donna J.; Richardson, John G.

    1995-01-01

    A rear-seat air bag restraint device is disclosed that prevents an individual, or individuals, from continuing violent actions while being transported in a patrol vehicle's rear seat without requiring immediate physical contact by the law enforcement officer. The air bag is activated by a control switch in the front seat and inflates to independently restrict the amount of physical activity occurring in the rear seat of the vehicle while allowing the officer to safely stop the vehicle. The air bag can also provide the officer additional time to get backup personnel to aid him if the situation warrants it. The bag is inflated and maintains a constant pressure by an air pump.

  14. Air bag restraint device

    DOEpatents

    Marts, D.J.; Richardson, J.G.

    1995-10-17

    A rear-seat air bag restraint device is disclosed that prevents an individual, or individuals, from continuing violent actions while being transported in a patrol vehicle`s rear seat without requiring immediate physical contact by the law enforcement officer. The air bag is activated by a control switch in the front seat and inflates to independently restrict the amount of physical activity occurring in the rear seat of the vehicle while allowing the officer to safely stop the vehicle. The air bag can also provide the officer additional time to get backup personnel to aid him if the situation warrants it. The bag is inflated and maintains a constant pressure by an air pump. 8 figs.

  15. 21 CFR 866.5620 - Alpha-2-macroglobulin immunological test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Alpha-2-macroglobulin immunological test system. 866.5620 Section 866.5620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5620 Alpha-2-macroglobulin...

  16. Genetics Home Reference: alpha-mannosidosis

    MedlinePlus

    ... Me Understand Genetics Home Health Conditions alpha-mannosidosis alpha-mannosidosis Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Alpha-mannosidosis is a rare inherited disorder that causes ...

  17. 40 CFR 58.15 - Annual air monitoring data certification.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 5 2011-07-01 2011-07-01 false Annual air monitoring data certification. 58.15 Section 58.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) AMBIENT AIR QUALITY SURVEILLANCE Monitoring Network § 58.15 Annual air monitoring...

  18. 40 CFR 58.15 - Annual air monitoring data certification.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Annual air monitoring data certification. 58.15 Section 58.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) AMBIENT AIR QUALITY SURVEILLANCE Monitoring Network § 58.15 Annual air monitoring...

  19. Characterization of irradiated blends of alpha-tocopherol and UHMWPE.

    PubMed

    Oral, Ebru; Greenbaum, Evan S; Malhi, Arnaz S; Harris, William H; Muratoglu, Orhun K

    2005-11-01

    Adhesive/abrasive wear in ultra-high molecular weight polyethylene (UHMWPE) has been minimized by radiation cross-linking. Irradiation is followed by melting to eliminate residual free radicals and avoid long-term oxidative embrittlement. However, post-irradiation melting reduces the crystallinity of the polymer and hence its strength and fatigue resistance. We proposed an alternative to post-irradiation melting to be the incorporation of the antioxidant alpha-tocopherol into UHMWPE prior to consolidation. alpha-Tocopherol is known to react with oxygen and oxidized lipids, stabilizing them against further oxidative degradation reactions. We blended GUR 1050 UHMWPE resin powder with alpha-tocopherol at 0.1 and 0.3 wt% and consolidated these blends. Then we gamma-irradiated these blends to 100-kGy. We characterized the effect of alpha-tocopherol on the cross-linking efficiency, oxidative stability, wear behavior and mechanical properties of the blends. (I) The cross-link density of virgin, 0.1 and 0.3 wt% alpha-tocopherol blended, 100-kGy irradiated UHMWPEs were 175+/-19, 146+/-4 and 93+/-4 mol/m3, respectively. (II) Maximum oxidation indices for 100-kGy irradiated UHMWPE previously blended with 0, 0.1 and 0.3 wt% alpha-tocopherol that were subjected to accelerated aging at 80 degrees C in air for 5 weeks were 3.32, 0.09, and 0.05, respectively. (III) The pin-on-disc wear rates of 100-kGy irradiated UHMWPE previously blended with 0.1 and 0.3 wt% alpha-tocopherol that were subjected to accelerated aging at 80 degrees C in air for 5 weeks were 2.10+/-0.17 and 5.01+/-0.76 mg/million cycles, respectively. (IV) Both accelerated aged, alpha-tocopherol-blended 100-kGy irradiated UHMWPEs showed higher ultimate tensile strength, higher yield strength, and lower elastic modulus when compared to 100-kGy irradiated, virgin UHMWPE. These results showed that alpha-tocopherol-blended 100-kGy irradiated UHMWPEs were not cross-linked to the same extent as the 100-kGy irradiated

  20. The effect of alpha-tocopherol on the oxidation and free radical decay in irradiated UHMWPE.

    PubMed

    Oral, Ebru; Rowell, Shannon L; Muratoglu, Orhun K

    2006-11-01

    We developed a radiation cross-linked ultra-high molecular weight polyethylene (UHMWPE) stabilized with alpha-tocopherol (Vitamin E) as a bearing material in total joint replacements. The stabilizing effect of alpha-tocopherol on free radical reactions in UHMWPE is not well understood. We investigated the effect of alpha-tocopherol on the oxidation and transformation of residual free radicals during real-time aging of alpha-tocopherol-doped, irradiated UHMWPE (alphaTPE) and irradiated UHMWPE (control). Samples were aged at 22 degrees C (room temperature) in air, at 40 degrees C in air and at 40 degrees C in water for 7 months. During the first month, alphaTPE showed some oxidation at the surface, which stayed constant thereafter. Control exhibited substantial oxidation in the subsurface region, which increased with time. The alkyl/allyl free radicals transformed to oxygen centered ones in both materials; this transformation occurred faster in alpha-TPE. In summary, the real-time oxidation behavior of alpha-TPE was consistent with that observed using accelerated aging methods. This new UHMWPE is oxidation resistant and is expected to maintain its properties in the long term.

  1. Radon measurement of natural gas using alpha scintillation cells.

    PubMed

    Kitto, Michael E; Torres, Miguel A; Haines, Douglas K; Semkow, Thomas M

    2014-12-01

    Due to their sensitivity and ease of use, alpha-scintillation cells are being increasingly utilized for measurements of radon ((222)Rn) in natural gas. Laboratory studies showed an average increase of 7.3% in the measurement efficiency of alpha-scintillation cells when filled with less-dense natural gas rather than regular air. A theoretical calculation comparing the atomic weight and density of air to that of natural gas suggests a 6-7% increase in the detection efficiency when measuring radon in the cells. A correction is also applicable when the sampling location and measurement laboratory are at different elevations. These corrections to the measurement efficiency need to be considered in order to derive accurate concentrations of radon in natural gas.

  2. Alpha-particle spectrometer experiment

    NASA Technical Reports Server (NTRS)

    Gorenstein, P.; Bjorkholm, P.

    1972-01-01

    Mapping the radon emanation of the moon was studied to find potential areas of high activity by detection of radon isotopes and their daughter products. It was felt that based on observation of regions overflown by Apollo spacecraft and within the field of view of the alpha-particle spectrometer, a radon map could be constructed, identifying and locating lunar areas of outgassing. The basic theory of radon migration from natural concentrations of uranium and thorium is discussed in terms of radon decay and the production of alpha particles. The preliminary analysis of the results indicates no significant alpha emission.

  3. Continuous and passive environmental radon monitoring: Measuring methods and health effects. (Latest citations from the INSPEC: Information services for the Physics and Engineering Communities database). Published Search

    SciTech Connect

    1993-08-01

    The bibliography contains citations concerning continuous and passive radon (Rn) monitoring, measurement methods and equipment, and health effects from Rn concentration in air, water, and soils. Citations discuss the design, development, and evaluation of monitoring and detection devices, including alpha spectroscopy and dosimetry, track detecting and scintillation, thermoluminescent, electret, and electrode collection. Sources of Rn concentration levels found in building materials, ventilation systems, soils, and ground water are examined. Lung cancer-associated risks from Rn radiation exposure are explored. Radon monitoring in mining operations is excluded. (Contains a minimum of 210 citations and includes a subject term index and title list.)

  4. Alpha detection as a probe for counter proliferation

    SciTech Connect

    Koster, J.E.; Johnson, J.P.; MacArthur, D.W.; Walters, S.G.

    1994-07-01

    An indication of the presence of special nuclear material (SNM) can be obtained by the detection of alpha particles from the decay of the SNM. Current techniques for detecting alpha particles have a number of limitations. Sensitive conventional detection of SNM traces involves off-site laboratory analysis -- but at the loss of an on-site confirmation. Fieldable detection instruments, on the other hand, are delicate and have poor sensitivity. New long-range alpha detection (LRAD) technology mitigates these limitations. An LRAD-based instrument relies on the detection of the hundreds of thousands of ions produced in ambient air by one emitted alpha particle. The ions can be transported to an ion detector at a distance much greater than the range of the original alpha particle. The LRAD-based monitors have the characteristics of high sensitivity, fast (real-time) response, ruggedness, and reliability. Many of the designs are quite portable. In this paper, several scenarios are identified for which particular LRAD-based detectors can provide confirmation of proliferation activity.

  5. Solid waste combustion for alpha waste incineration

    SciTech Connect

    Orloff, D.I.

    1981-02-01

    Radioactive waste incinerator development at the Savannah River Laboratory has been augmented by fundamental combustion studies at the University of South Carolina. The objective was to measure and model pyrolysis and combustion rates of typical Savannah River Plant waste materials as a function of incinerator operating conditions. The analytical models developed in this work have been incorporated into a waste burning transient code. The code predicts maximum air requirement and heat energy release as a function of waste type, package size, combustion chamber size, and temperature. Historically, relationships have been determined by direct experiments that did not allow an engineering basis for predicting combustion rates in untested incinerators. The computed combustion rates and burning times agree with measured values in the Savannah River Laboratory pilot (1 lb/hr) and full-scale (12 lb/hr) alpha incinerators for a wide variety of typical waste materials.

  6. 78 FR 50138 - Applications for Certificates of Public Convenience and Necessity and Foreign Air Carrier Permits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-16

    ... PanAir requesting a foreign air carrier permit to operate charter air transportation of property..., whether or not it constitutes part of a continuous operation that includes service to Panama. PanAir...

  7. 40 CFR 81.88 - Billings Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air...: Region II. 481.169Helena Intrastate Air Quality Control Region: Region IV. 481.170Miles City...

  8. 40 CFR 81.88 - Billings Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air...: Region II. 481.169Helena Intrastate Air Quality Control Region: Region IV. 481.170Miles City...

  9. 40 CFR 52.499 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.499 Section 52.499 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  10. 40 CFR 52.1603 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.1603 Section 52.1603 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  11. 40 CFR 52.432 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.432 Section 52.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulation for preventing significant deterioration of air quality. The provisions...

  12. 40 CFR 52.632 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.632 Section 52.632 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  13. 40 CFR 52.2827 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.2827 Section 52.2827 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  14. 40 CFR 52.2676 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.2676 Section 52.2676 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  15. 40 CFR 52.499 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.499 Section 52.499 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  16. 40 CFR 52.499 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.499 Section 52.499 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  17. 40 CFR 52.2827 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.2827 Section 52.2827 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  18. 40 CFR 52.2729 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.2729 Section 52.2729 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  19. 40 CFR 52.499 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.499 Section 52.499 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  20. 40 CFR 52.432 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.432 Section 52.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulation for preventing significant deterioration of air quality. The provisions...

  1. 40 CFR 52.683 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.683 Section 52.683 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The State of Idaho Rules for Control of Air Pollution in Idaho, specifically... the Clean Air Act for preventing significant deterioration of air quality. (b) The requirements...

  2. 40 CFR 52.793 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.793 Section 52.793 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  3. 40 CFR 52.1884 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.1884 Section 52.1884 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  4. 40 CFR 52.738 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.738 Section 52.738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  5. 40 CFR 52.1165 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.1165 Section 52.1165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulation for preventing significant deterioration of air quality....

  6. 40 CFR 52.2729 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.2729 Section 52.2729 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  7. 40 CFR 52.793 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.793 Section 52.793 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  8. 40 CFR 52.1884 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.1884 Section 52.1884 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  9. 40 CFR 52.1884 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.1884 Section 52.1884 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  10. 40 CFR 52.1165 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.1165 Section 52.1165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulation for preventing significant deterioration of air quality....

  11. 40 CFR 52.2497 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.2497 Section 52.2497 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  12. 40 CFR 52.793 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.793 Section 52.793 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  13. 40 CFR 52.1603 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.1603 Section 52.1603 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  14. 40 CFR 52.1180 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.1180 Section 52.1180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  15. 40 CFR 52.738 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.738 Section 52.738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  16. 40 CFR 52.793 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.793 Section 52.793 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  17. 40 CFR 52.2676 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.2676 Section 52.2676 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  18. 40 CFR 52.2497 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.2497 Section 52.2497 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  19. 40 CFR 52.632 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.632 Section 52.632 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  20. 40 CFR 52.2729 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.2729 Section 52.2729 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  1. 40 CFR 52.96 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.96 Section 52.96 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The State of Alaska Department of Environmental Conservation Air Quality... deterioration of air quality. (b) The requirements of sections 160 through 165 of the Clean Air Act are not...

  2. 40 CFR 52.1603 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.1603 Section 52.1603 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  3. 40 CFR 52.2676 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.2676 Section 52.2676 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  4. 40 CFR 52.2497 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.2497 Section 52.2497 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  5. 40 CFR 52.1603 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.1603 Section 52.1603 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  6. 40 CFR 52.2827 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.2827 Section 52.2827 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  7. 40 CFR 52.2779 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.2779 Section 52.2779 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  8. 40 CFR 52.683 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.683 Section 52.683 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The State of Idaho Rules for Control of Air Pollution in Idaho, specifically... Air Act for preventing significant deterioration of air quality. (b) The requirements of sections...

  9. 40 CFR 52.432 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.432 Section 52.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulation for preventing significant deterioration of air quality. The provisions...

  10. 40 CFR 52.1180 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.1180 Section 52.1180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  11. 40 CFR 52.2497 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.2497 Section 52.2497 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  12. 40 CFR 52.632 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.632 Section 52.632 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  13. 40 CFR 52.1180 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.1180 Section 52.1180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  14. 40 CFR 52.1165 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.1165 Section 52.1165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulation for preventing significant deterioration of air quality....

  15. 40 CFR 52.2729 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.2729 Section 52.2729 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  16. 40 CFR 52.738 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.738 Section 52.738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  17. 40 CFR 52.632 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.632 Section 52.632 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  18. 40 CFR 52.2497 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.2497 Section 52.2497 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  19. 40 CFR 52.1165 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.1165 Section 52.1165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulation for preventing significant deterioration of air quality....

  20. 40 CFR 52.2827 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.2827 Section 52.2827 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  1. 40 CFR 52.2729 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.2729 Section 52.2729 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  2. 40 CFR 52.2779 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.2779 Section 52.2779 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  3. 40 CFR 52.1180 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.1180 Section 52.1180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  4. 40 CFR 52.632 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.632 Section 52.632 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  5. 40 CFR 52.1603 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.1603 Section 52.1603 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  6. 40 CFR 52.738 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.738 Section 52.738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  7. 40 CFR 52.683 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.683 Section 52.683 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The State of Idaho Rules for Control of Air Pollution in Idaho, specifically... the Clean Air Act for preventing significant deterioration of air quality. (b) The requirements...

  8. 40 CFR 52.2676 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.2676 Section 52.2676 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  9. 40 CFR 52.2779 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.2779 Section 52.2779 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  10. 40 CFR 52.1165 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.1165 Section 52.1165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulation for preventing significant deterioration of air quality....

  11. 40 CFR 52.1180 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.1180 Section 52.1180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  12. 40 CFR 52.2779 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.2779 Section 52.2779 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  13. 40 CFR 52.2676 - Significant deterioration of air quality.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quality. 52.2676 Section 52.2676 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  14. 40 CFR 52.738 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.738 Section 52.738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air Act are not met... air quality. (b) Regulations for preventing significant deterioration of air quality. The...

  15. 40 CFR 52.2827 - Significant deterioration of air quality.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... quality. 52.2827 Section 52.2827 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  16. 40 CFR 52.1884 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.1884 Section 52.1884 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  17. 40 CFR 52.683 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.683 Section 52.683 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... deterioration of air quality. (a) The State of Idaho Rules for Control of Air Pollution in Idaho, specifically... the Clean Air Act for preventing significant deterioration of air quality. (b) The requirements...

  18. 40 CFR 52.499 - Significant deterioration of air quality.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quality. 52.499 Section 52.499 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  19. 40 CFR 52.1689 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.1689 Section 52.1689 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  20. 40 CFR 52.2779 - Significant deterioration of air quality.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quality. 52.2779 Section 52.2779 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  1. 40 CFR 52.1884 - Significant deterioration of air quality.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quality. 52.1884 Section 52.1884 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Significant deterioration of air quality. (a) The requirements of sections 160 through 165 of the Clean Air... deterioration of air quality. (b) Regulations for preventing significant deterioration of air quality....

  2. Propagation or failure of detonation across an air gap in an LX-17 column: continuous time-dependent detonation or shock speed using the Embedded Fiber Optic (EFO) technique

    SciTech Connect

    Hare, D E; Chandler, J B; Compton, S M; Garza, R G; Grimsley, D A; Hernandez, A; Villafana, R J; Wade, J T; Weber, S R; Wong, B M; Souers, P C

    2008-01-16

    The detailed history of the shock/detonation wave propagation after crossing a room-temperature-room-pressure (RTP) air gap between a 25.4 mm diameter LX-17 donor column and a 25.4 mm diameter by 25.4 mm long LX-17 acceptor pellet is investigated for three different gap widths (3.07, 2.08, and 0.00 mm) using the Embedded Fiber Optic (EFO) technique. The 2.08 mm gap propagated and the 3.07 mm gap failed and this can be seen clearly and unambiguously in the EFO data even though the 25.4 mm-long acceptor pellet would be considered quite short for a determination by more traditional means such as pins.

  3. Alpha--College for Exploring

    ERIC Educational Resources Information Center

    Leppert, William; Koenig, Joan

    1976-01-01

    Describes Alpha, the experimental college of individualized instruction at the College of DuPage (Illinois). At this college, students design their own curricula and work in an open classroom situation, and teachers start with students instead of subjects. (DC)

  4. Genetics Home Reference: alpha thalassemia

    MedlinePlus

    ... in each cell. Each copy is called an allele. For each gene, one allele is inherited from a person's father, and the ... person's mother. As a result, there are four alleles that produce alpha-globin. The different types of ...

  5. Detecting Alpha-1 Antitrypsin Deficiency.

    PubMed

    Stoller, James K

    2016-08-01

    Alpha-1 antitrypsin deficiency is a widely underrecognized condition, with evidence of persisting long diagnostic delays and patients' frequent need to see multiple physicians before initial diagnosis. Reasons for underrecognition include inadequate understanding of alpha-1 antitrypsin deficiency by physicians and allied health care providers; failure to implement available, guideline-based practice recommendations; and the belief that effective therapy is unavailable. Multiple studies have described both the results of screening and targeted detection of individuals with alpha-1 antitrypsin deficiency, with both varying strategies employed to identify at-risk individuals and varying results of testing. Also, various strategies to enhance detection of affected individuals have been examined, including use of the electronic medical record to prompt testing and empowerment of allied health providers, especially respiratory therapists, to promote testing for alpha-1 antitrypsin deficiency. Such efforts are likely to enhance detection with the expected result that the harmful effects of delayed diagnosis can be mitigated. PMID:27564667

  6. Alpha Magnetic Spectrometer (AMS) Overview

    NASA Video Gallery

    The Alpha Magnetic Spectrometer (AMS) is flying to the station on STS-134. The AMS experiment is a state-of-the-art particle physics detector being operated by an international team composed of 60 ...

  7. Synthesis and herbicidal activity of novel alpha,alpha,alpha-trifluoro-m-tolyl pyridazinone derivatives.

    PubMed

    Xu, Han; Zou, Xiao-Mao; Zhu, You-Quan; Liu, Bin; Tao, Han-Lin; Hu, Xu-Hong; Song, Hai-Bin; Hu, Fang-Zhong; Wang, Yong; Yang, Hua-Zheng

    2006-06-01

    A series of novel alpha,alpha,alpha-trifluoro-m-tolyl pyridazinone derivatives was synthesised. Herbicidal activities of the two intermediate compounds and 15 pyridazinone derivatives were evaluated through barnyardgrass and rape cup tests and Spirodela polyrrhiza (L.) Schleiden tests. Selected compounds were also evaluated under greenhouse conditions. Bleaching activities were observed at 10 microg ml(-1) and some compounds exhibited herbicidal activities at a rate of 300 g ha(-1). The relationship between crystal structures and herbicidal activities is discussed through a comparison of two compounds (5a and 5f). PMID:16602079

  8. Alpha decay in electron surrounding

    SciTech Connect

    Igashov, S. Yu.; Tchuvil’sky, Yu. M.

    2013-12-15

    The influence of atomic electron shells on the constant of alpha decay of heavy and mediummass nuclei was considered in detail. A method for simultaneously taking into account the change in the potential-barrier shape and the effect of reflection of a diverging Coulomb wave in the classically allowed region was developed. The ratios of decay probabilities per unit time for a bare nucleus and the respective neutral atom were found for some alpha-decaying isotopes.

  9. 40 CFR 63.8690 - How do I monitor and collect data to demonstrate continuous compliance?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Asphalt Processing and Asphalt Roofing Manufacturing Continuous Compliance Requirements § 63.8690 How do I...

  10. 40 CFR 63.8690 - How do I monitor and collect data to demonstrate continuous compliance?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Asphalt Processing and Asphalt Roofing Manufacturing Continuous Compliance Requirements § 63.8690 How do I...

  11. 40 CFR 63.8690 - How do I monitor and collect data to demonstrate continuous compliance?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Asphalt Processing and Asphalt Roofing Manufacturing Continuous Compliance Requirements § 63.8690 How do I...

  12. 40 CFR 63.8690 - How do I monitor and collect data to demonstrate continuous compliance?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Asphalt Processing and Asphalt Roofing Manufacturing Continuous Compliance Requirements § 63.8690 How do I...

  13. 40 CFR 63.8690 - How do I monitor and collect data to demonstrate continuous compliance?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Asphalt Processing and Asphalt Roofing Manufacturing Continuous Compliance Requirements § 63.8690 How do I...

  14. Alpha counting and spectrometry using liquid scintillation methods

    SciTech Connect

    McDowell, W J

    1986-01-01

    The material in this report is intended to be a practical introduction and guide to the use of liquid scintillation for alpha counting and spectrometry. Other works devoted to the development of the theory of liquid scintillation exist and a minimum of such material is repeated here. Much remains to be learned and many improvements remain to be made in the use of liquid scintillation for alpha counting and spectrometry. It is hoped that this modest work will encourage others to continue development in the field.

  15. Unique pitch evolution in the smectic-C+alpha phase.

    PubMed

    Liu, Z Q; McCoy, B K; Wang, S T; Pindak, R; Caliebe, W; Barois, P; Fernandes, P; Nguyen, H T; Hsu, C S; Wang, Shun; Huang, C C

    2007-08-17

    Employing resonant x-ray diffraction, we observed unique pitch evolutions in the smectic-C*(alpha) phase in mixtures of two antiferroelectric liquid crystals. Our results show that the pitch in this phase continuously evolves across 4 layers, contradicting a theoretical model that predicts that the smectic-C*(FI2) phase intervenes in the smectic-C*(alpha) phase. The phase sequences we found can be explained by another model that includes one type of long-range interaction among smectic layers.

  16. Unique Pitch Evolution in the Smectic -C-alpha* Phase

    SciTech Connect

    Liu,Z.; McCoy, B.; Wang, S.; Pindak, R.; Caliebe, W.; Barois, P.; Fernandes, P.; Nguyen, H.; Hsu, C.; Wang, .

    2007-01-01

    Employing resonant x-ray diffraction, we observed unique pitch evolutions in the smectic-C{alpha}* phase in mixtures of two antiferroelectric liquid crystals. Our results show that the pitch in this phase continuously evolves across 4 layers, contradicting a theoretical model that predicts that the smectic-C{sub FI2}* phase intervenes in the smectic-C{alpha}* phase. The phase sequences we found can be explained by another model that includes one type of long-range interaction among smectic layers.

  17. Air Pollution.

    ERIC Educational Resources Information Center

    Fox, Donald L.

    1989-01-01

    Materials related to air pollution are reviewed for the period January 1987, to October 1988. The topics are pollution monitoring, air pollution, and environmental chemistry. The organization consists of two major analytical divisions: (1) gaseous methods; and (2) aerosol and particulate methods. (MVL)

  18. Air Pollution.

    EPA Science Inventory

    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. Neutralising antibodies in patients with multiple myeloma receiving maintenance therapy with interferon alpha 2b.

    PubMed Central

    Bell, J. B.; Barfoot, R.; Iveson, T.; Powles, R. L.; Millar, B. C.

    1994-01-01

    In a study of 29 patients who were receiving or had received interferon alpha 2b (IFN-alpha 2b) as maintenance therapy for multiple myeloma, antibodies were detected in 58% (17/29) of patients measured by a solid-phase enzyme-linked immunosorbent assay (ELISA). Only 7/17 patients who were positive for antibody in the ELISA had neutralising antibody to IFN-alpha 2b, measured by virus growth inhibition. These patients comprised six who were receiving IFN-alpha 2b at the time of assessment and one who had finished treatment. Among patients who were receiving the cytokine, four had progressive disease, one was in complete remission and one in partial remission. Neutralising activity was also detected to natural human leucocyte IFN-alpha in the same patients. Two patients who were positive for neutralising antibody remain in remission and are continuing to receive IFN-alpha 2b. These two patients have since lost their neutralising titre. No neutralising antibody to IFN-alpha 2b or natural human leucocyte IFN-alpha was detected in serum from six normal donors. The data suggest that neutralising antibody formation in patients with multiple myeloma is not responsible for relapse in patients receiving IFN-alpha 2b. The transient nature of neutralising antibody production in patients who remain in remission suggests that this response to IFN-alpha 2b is not associated with memory B cells. PMID:7917911

  20. Alpha-beta monitoring system based on pair of simultaneous Multi-Wire Proportional Counters

    NASA Astrophysics Data System (ADS)

    Wengrowicz, U.; Amidan, D.; Orion, I.

    2016-08-01

    A new approach for a simultaneous alpha-beta Multi-wire Proportional Counter (MWPC) is presented. The popular approach for alpha-beta monitoring systems consists of a large area MWPC using noble gas flow such as Argon Methane. This method of measurement is effective but requires large-scale and expensive maintenance due to the needs of gas flow control and periodic replacements. In this work, a pair of simultaneous MWPCs for alpha-beta measuring is presented. The developed detector consists of a sealed gas MWPC sensor for beta particles, behind a free air alpha sensor. This approach allows effective simultaneous detection and discrimination of both alpha and beta radiation without the maintenance cost noble gas flow required for unsealed detectors.

  1. Effect of a grounded object on radon measurement using AlphaGUARD.

    PubMed

    Ichitsubo, Hirokazu; Yamada, Yuji

    2004-07-01

    ABSTRACT-: The effects on radon concentration measurement of a grounded object near the opening of a cylindrical ionization chamber were studied using AlphaGUARD. AlphaGUARD comes with a flow measurement adapter that fits on the front of the AlphaGUARD ionization chamber. If the adapter nozzle is grounded, the radon concentration is falsely measured at 0 Bq m. A metal connector for use between the AlphaGUARD and the air duct wall was manufactured in our laboratory. When the connector is grounded, the radon concentration is again falsely measured as 0 Bq m. If the nozzle or connector is ungrounded, the AlphaGUARD measures radon concentration accurately. Health Phys. PMID:15194926

  2. The portable device for continual measurement of radon progenies on filter using the detector Timepix.

    PubMed

    Bulanek, Boris; Hulka, Jiri; Jilek, Karel; Stekl, Ivan

    2015-06-01

    In this article, a portable device was presented for continual measuring of equilibrium equivalent concentration (EEC) of (222)Rn based on the Timepix detector with 300-µm-thick active layer. In order to have a portable device, a filtration head was developed for collecting short-lived radon progenies attached on aerosols. The short-lived progenies are estimated from analysing alphas from decay of (218,214)Po from Millipore filter after termination of filtration. Comparison with beta measurement was done as well. The dependence of EEC on an air flow and filtration time was studied. The low-level detection limit for EEC was estimated from the last 10 min of 3-h decay measurement and was found in the range of 40-70 Bq m(-3). EEC was measured in National Radiation Protection Institute radon chamber, and results were compared with the commercial detector Fritra4. PMID:25990115

  3. 21 CFR 882.1610 - Alpha monitor.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Alpha monitor. 882.1610 Section 882.1610 Food and... NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1610 Alpha monitor. (a) Identification. An alpha... electroencephalogram which is referred to as the alpha wave. (b) Classification. Class II (performance standards)....

  4. 21 CFR 882.1610 - Alpha monitor.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Alpha monitor. 882.1610 Section 882.1610 Food and... NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1610 Alpha monitor. (a) Identification. An alpha... electroencephalogram which is referred to as the alpha wave. (b) Classification. Class II (performance standards)....

  5. 21 CFR 882.1610 - Alpha monitor.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Alpha monitor. 882.1610 Section 882.1610 Food and... NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1610 Alpha monitor. (a) Identification. An alpha... electroencephalogram which is referred to as the alpha wave. (b) Classification. Class II (performance standards)....

  6. 46 CFR 154.345 - Air locks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Air locks. 154.345 Section 154.345 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Ship Arrangements § 154.345 Air locks. (a) An air lock may...

  7. Binding of actin to lens alpha crystallins

    NASA Technical Reports Server (NTRS)

    Gopalakrishnan, S.; Takemoto, L.; Spooner, B. S. (Principal Investigator)

    1992-01-01

    Actin has been coupled to a cyanogen bromide-activated Sepharose 4B column, then tested for binding to alpha, beta, and gamma crystallin preparations from the bovine lens. Alpha, but not beta or gamma, crystallins bound to the actin affinity column in a time dependent and saturable manner. Subfractionation of the alpha crystallin preparation into the alpha-A and alpha-B species, followed by incubation with the affinity column, demonstrated that both species bound approximately the same. Together, these studies demonstrate a specific and saturable binding of lens alpha-A and alpha-B with actin.

  8. 29 CFR 1917.155 - Air receivers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 7 2013-07-01 2013-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed...

  9. [Alpha-Synuclein in blood and cerebrospinal fluid of patients with alpha-synucleinopathy].

    PubMed

    Ono, Kenjiro; Yamada, Masahito

    2014-03-01

    Alpha-Synuclein protein(alphaS) aggregates from a monomer to assemblies such as oligomers, protofibrils, and mature fibrils. The early intermediate aggregate, that is, the oligomer, has been reported to be the most toxic species. We recently reported that melatonin inhibits alphaS aggregation, including protofibril and oligomer formations. While the alphaS concentration in cerebrospinal fluid was reported to significantly decrease in patients with Parkinson's disease (PD) and dementia with Lewy bodies, there have been reports that the alphaS oligomer concentration was elevated in the cerebrospinal fluid of PD patients. Moreover, it was reported that the alphaS oligomer concentration was also elevated in the blood of PD patients. Further studies may establish alphaS in cerebrospinal fluid and blood as a biomarker of alpha-synucleinopathies, including PD.

  10. Continuous aqueous tritium monitor

    DOEpatents

    McManus, Gary J.; Weesner, Forrest J.

    1989-05-30

    An apparatus for a selective on-line determination of aqueous tritium concentration is disclosed. A moist air stream of the liquid solution being analyzed is passed through a permeation dryer where the tritium and moisture and selectively removed to a purge air stream. The purge air stream is then analyzed for tritium concentration, humidity, and temperature, which allows computation of liquid tritium concentration.

  11. Mechanism of alpha-tocopheryl-phosphate (alpha-TP) transport across the cell membrane

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have reported that alpha-TP is synthesized and hydrolyzed in animal cells and tissues; it modulates also several cell functions (FRBM 39:970, and UBMB Life, 57:23, 2005). While it is similar to alpha-tocopherol (alpha-T), alpha-TP appears to be more potent than alpha-T in inhibiting cell prolifer...

  12. Binding of [alpha, alpha]-Disubstituted Amino Acids to Arginase Suggests New Avenues for Inhibitor Design

    SciTech Connect

    Ilies, Monica; Di Costanzo, Luigi; Dowling, Daniel P.; Thorn, Katherine J.; Christianson, David W.

    2011-10-21

    Arginase is a binuclear manganese metalloenzyme that hydrolyzes L-arginine to form L-ornithine and urea, and aberrant arginase activity is implicated in various diseases such as erectile dysfunction, asthma, atherosclerosis, and cerebral malaria. Accordingly, arginase inhibitors may be therapeutically useful. Continuing our efforts to expand the chemical space of arginase inhibitor design and inspired by the binding of 2-(difluoromethyl)-L-ornithine to human arginase I, we now report the first study of the binding of {alpha},{alpha}-disubstituted amino acids to arginase. Specifically, we report the design, synthesis, and assay of racemic 2-amino-6-borono-2-methylhexanoic acid and racemic 2-amino-6-borono-2-(difluoromethyl)hexanoic acid. X-ray crystal structures of human arginase I and Plasmodium falciparum arginase complexed with these inhibitors reveal the exclusive binding of the L-stereoisomer; the additional {alpha}-substituent of each inhibitor is readily accommodated and makes new intermolecular interactions in the outer active site of each enzyme. Therefore, this work highlights a new region of the protein surface that can be targeted for additional affinity interactions, as well as the first comparative structural insights on inhibitor discrimination between a human and a parasitic arginase.

  13. Workshop on Precision Measurements of $\\alpha_s$

    SciTech Connect

    Bethke, Siegfried; Hoang, Andre H.; Kluth, Stefan; Schieck, Jochen; Stewart, Iain W.; Aoki, S.; Beneke, M.; Bethke, S.; Blumlein, J.; Brambilla, N.; Brodsky, S.; /MIT, LNS

    2011-10-01

    These are the proceedings of the Workshop on Precision Measurements of {alpha}{sub s} held at the Max-Planck-Institute for Physics, Munich, February 9-11, 2011. The workshop explored in depth the determination of {alpha}{sub s}(m{sub Z}) in the {ovr MS} scheme from the key categories where high precision measurements are currently being made, including DIS and global PDF fits, {tau}-decays, electro-weak precision observables and Z-decays, event-shapes, and lattice QCD. These proceedings contain a short summary contribution from the speakers, as well as the lists of authors, conveners, participants, and talks.

  14. Microbial metabolism of steviol and steviol-16alpha,17-epoxide.

    PubMed

    Yang, Li-Ming; Hsu, Feng-Lin; Chang, Shwu-Fen; Cheng, Juei-Tang; Hsu, Ju-Yin; Hsu, Chung-Yi; Liu, Pan-Chun; Lin, Shwu-Jiuan

    2007-02-01

    Steviol (2) possesses a blood glucose-lowering property. In order to produce potentially more- or less-active, toxic, or inactive metabolites compared to steviol (2), its microbial metabolism was investigated. Incubation of 2 with the microorganisms Bacillus megaterium ATCC 14581, Mucor recurvatus MR 36, and Aspergillus niger BCRC 32720 yielded one new metabolite, ent-7alpha,11beta,13-trihydroxykaur-16-en-19-oic acid (7), together with four known related biotransformation products, ent-7alpha,13-dihydroxykaur-16-en-19-oic acid (3), ent-13-hydroxykaur-16-en-19-alpha-d-glucopyranosyl ester (4), ent-13,16beta,17-trihydroxykauran-19-oic acid (5), and ent-13-hydroxy-7-ketokaur-16-en-19-oic acid (6). The preliminary testing of antihyperglycemic effects showed that 5 was more potent than the parent compound (2). Thus, the microbial metabolism of steviol-16alpha,17-epoxide (8) with M. recurvatus MR 36 was continued to produce higher amounts of 5 for future study of its action mechanism. Preparative-scale fermentation of 8 yielded 5, ent-11alpha,13,16alpha,17-tetrahydroxykauran-19-oic acid (10), ent-1beta,17-dihydroxy-16-ketobeyeran-19-oic acid (11), and ent-7alpha,17-dihydroxy-16-ketobeyeran-19-oic acid (13), together with three new metabolites: ent-13,16beta-dihydroxykauran-17-acetoxy-19-oic acid (9), ent-11beta,13-dihydroxy-16beta,17-epoxykauran-19-oic acid (12), and ent-11beta,13,16beta,17-tetrahydroxykauran-19-oic acid (14). The structures of the compounds were fully elucidated using 1D and 2D NMR spectroscopic techniques, as well as HRFABMS. In addition, a GRE (glucocorticoid responsive element)-mediated luciferase reporter assay was used to initially screen the compounds 3-5, and 7 as glucocorticoid agonists. Compounds 4, 5 and 7 showed significant effects. PMID:17207824

  15. Air Pollution

    MedlinePlus

    ... tobacco smoke. How is air pollution linked to climate change? While climate change is a global process, it ... ozone levels are also a concern. Impacts of Climate Change on Human Health in the United States: A ...

  16. Air Apparent.

    ERIC Educational Resources Information Center

    Harbster, David A.

    1988-01-01

    Explains the principle upon which a barometer operates. Describes how to construct two barometric devices for use in the classroom that show air's changing pressure. Cites some conditions for predicting weather. (RT)

  17. Alpha detection in pipes using an inverting membrane scintillator

    SciTech Connect

    Kendrick, D.T.; Cremer, C.D.; Lowry, W.; Cramer, E.

    1995-12-31

    Characterization of surface alpha emitting contamination inside enclosed spaces such as piping systems presents an interesting radiological measurement challenge. Detection of these alpha particles from the exterior of the pipe is impossible since the alpha particles are completely absorbed by the pipe wall. Traditional survey techniques, using hand-held instruments, simply can not be used effectively inside pipes. Science and Engineering Associates, Inc. is currently developing an enhancement to its Pipe Explorer{trademark} system that will address this challenge. The Pipe Explorer{trademark} uses a unique sensor deployment method where an inverted tubular membrane is propagated through complex pipe runs via air pressure. The inversion process causes the membrane to fold out against the pipe wall, such that no part of the membrane drags along the pipe wall. This deployment methodology has been successfully demonstrated at several DOE sites to transport specially designed beta and gamma scintillation detectors into pipes ranging in length up to 250 ft. The measurement methodology under development overcomes the limitations associated with conventional hand-held survey instruments by remotely emplacing an alpha scintillator in direct contact with the interior pipe surface over the entire length to be characterized. This is accomplished by incorporating a suitable scintillator into the otherwise clear membrane material. Alpha particles emitted from the interior pipe surface will intersect the membrane, resulting in the emission of light pulses from the scintillator. A photodetector, towed by the inverting membrane, is used to count these light pulses as a function of distance into the pipe, thereby producing a log of the surface alpha contamination levels. It is anticipated that the resulting system will be able to perform measurements in pipes as small as two inches in diameter, and several hundred feet in length.

  18. Urban air

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    Air pollution and the risk of potential health effects are not sufficiently convincing reasons for people to stop driving their cars, according to a study by the Population Reference Bureau (PRB) released on November 18.While sufficient levels of suspended particulate matter, carbon monoxide, and lead can present health concerns, the study found that many people surveyed for the study were not convinced of the clear linkage between air pollution and health.

  19. The alpha gal story: Lessons learned from connecting the dots

    PubMed Central

    Steinke, John W; Platts-Mills, Thomas A.E.; Commins, Scott P

    2015-01-01

    Anaphylaxis is a severe allergic reaction that can be rapidly progressing and fatal; thus, establishing the etiology of anaphylaxis is pivotal to long-term risk management. Our recent work has identified a novel IgE antibody response to a mammalian oligosaccharide epitope, galactose-alpha-1,3-galactose (alpha-gal). IgE to alpha-gal has been associated with two distinct forms of anaphylaxis: i) immediate onset anaphylaxis during first exposure to intravenous cetuximab, and ii) delayed onset anaphylaxis 3–6 hours after ingestion of mammalian food products (e.g., beef and pork). Results of our studies and those of others strongly suggest that tick bites are a cause, if not the only significant cause, of IgE antibody responses to alpha-gal in the southern, eastern and central United States, Europe, Australia and parts of Asia. Typical immune responses to carbohydrates are considered to be T cell-independent, while IgE antibody production is thought to involve sequential class-switching that requires input from T cells. Therefore, establishing the mechanism of the specific IgE antibody response to alpha-gal will be an important aspect to address as this area of research continues. PMID:25747720

  20. Remission of liver fibrosis by interferon-alpha 2b.

    PubMed

    Moreno, M G; Muriel, P

    1995-08-01

    Fibrosis is a dynamic process associated with the continuous deposition and resorption of connective tissue, mainly collagen. Therapeutic strategies are emerging by which this dynamic process can be modulated. Since interferons are known to inhibit collagen production, the aim of this study was to investigate if the administration of interferon-alpha 2b (IFN-alpha) can restore the normal hepatic content of collagen in rats with established fibrosis. Fibrosis was induced by prolonged bile duct ligation. IFN-alpha (100,000 IU/rat/day; s.c.) was administered to fibrotic rats for 15 days. Bile duct ligation increased liver collagen content 6-fold. In addition, serum and liver markers of hepatic injury increased significantly; liver histology showed an increase in collagen deposition, and the normal architecture was lost, with large zones of necrosis being observed frequently. IFN-alpha administration reversed to normal the values of all the biochemical markers measured and restored the normal architecture of the liver. Our results demonstrated that IFN-alpha is useful in reversing fibrosis and liver damage induced by biliary obstruction in the rat. However, further investigations are required to evaluate the therapeutic relevance of interferons on non-viral fibrosis and cholestasis. PMID:7646558

  1. Nonlinear feedback control for high alpha flight

    NASA Technical Reports Server (NTRS)

    Stalford, Harold

    1990-01-01

    Analytical aerodynamic models are derived from a high alpha 6 DOF wind tunnel model. One detail model requires some interpolation between nonlinear functions of alpha. One analytical model requires no interpolation and as such is a completely continuous model. Flight path optimization is conducted on the basic maneuvers: half-loop, 90 degree pitch-up, and level turn. The optimal control analysis uses the derived analytical model in the equations of motion and is based on both moment and force equations. The maximum principle solution for the half-loop is poststall trajectory performing the half-loop in 13.6 seconds. The agility induced by thrust vectoring capability provided a minimum effect on reducing the maneuver time. By means of thrust vectoring control the 90 degrees pitch-up maneuver can be executed in a small place over a short time interval. The agility capability of thrust vectoring is quite beneficial for pitch-up maneuvers. The level turn results are based currently on only outer layer solutions of singular perturbation. Poststall solutions provide high turn rates but generate higher losses of energy than that of classical sustained solutions.

  2. MFTF-. cap alpha. + T progress report

    SciTech Connect

    Nelson, W.D.

    1985-04-01

    Early in FY 1983, several upgrades of the Mirror Fusion Test Facility (MFTF-B) at Lawrence Livermore National Laboratory (LLNL) were proposed to the fusion community. The one most favorably received was designated MFTF-..cap alpha..+T. The engineering design of this device, guided by LLNL, has been a principal activity of the Fusion Engineering Design Center during FY 1983. This interim progress report represents a snapshot of the device design, which was begun in FY 1983 and will continue for several years. The report is organized as a complete design description. Because it is an interim report, some parts are incomplete; they will be supplied as the design study proceeds. As described in this report, MFTF-..cap alpha..+T uses existing facilities, many MFTF-B components, and a number of innovations to improve on the physics parameters of MFTF-B. It burns deuterium-tritium and has a central-cell Q of 2, a wall loading GAMMA/sub n/ of 2 MW/m/sup 2/ (with a central-cell insert module), and an availability of 10%. The machine is fully shielded, allows hands-on maintenance of components outside the vacuum vessel 24 h after shutdown, and has provisions for repair of all operating components.

  3. Residential radon daughter monitor based on alpha spectroscopy

    SciTech Connect

    Nazaroff, W.W.

    1980-05-01

    The radioactive daughters of radon-222 pose a serious indoor air quality problem in some circumstances. A technique for measuring the concentrations of these radioisotopes in air is presented. The method involves drawing air through a filter; then, for two time intervals after sampling, counting the alpha decays from polonium-218 and polonium-214 on the filter. The time intervals are optimized to yield the maximum resolution between the individual daughter concentrations. For a total measurement time of 50 minutes, individual daughter concentrations of 1.0 nanocuries per cubic meter are measured with an uncertainty of 20%. A prototype of a field monitor based on this technique is described, as is a field test in which the prototype was used to measure radon daughter concentrations as a function of ventilation conditions in an energy-efficient house.

  4. alpha-Thalassemia caused by an unstable alpha-globin mutant.

    PubMed Central

    Liebhaber, S A; Kan, Y W

    1983-01-01

    In a previous study, molecular cloning of the alpha-globin genes from a patient with nondeletion Hb-H disease (genotype--/alpha alpha) showed that a single nucleotide mutation (CTG to CCG) in one of the genes resulted in a leucine to proline substitution. This paper describes the approach we used to detect the abnormal alpha-globin chain. The chain was identified using a cell-free translation system. It turned over rapidly both in vitro and in vivo in the patient's reticulocytes. The unusual feature of this unstable alpha-globin is that the alpha-globin deficiency causes alpha-thalassemia. Simple heterozygotes for this lesion (alpha Pro alpha/alpha alpha) resemble alpha-thalassemia carriers and do not exhibit the hemolytic anemia usually associated with unstable hemoglobins. Images PMID:6826718

  5. 40 CFR 81.59 - Cumberland-Keyser Interstate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.59 Cumberland-Keyser Interstate Air Quality Control Region. The Cumberland-Keyser Interstate Air Quality Control Region (Maryland-West Virginia) has been revised to...

  6. 40 CFR 81.16 - Metropolitan Denver Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.16 Metropolitan Denver Intrastate Air Quality Control Region. The Metropolitan Denver Intrastate Air Quality Control Region (Colorado) consists of the territorial...

  7. 40 CFR 81.43 - Metropolitan Toledo Interstate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.43 Metropolitan Toledo Interstate Air Quality Control Region. The Metropolitan Toledo Interstate Air Quality Control Region (Ohio-Michigan) consists of the territorial...

  8. 40 CFR 81.49 - Southeast Florida Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.49 Southeast Florida Intrastate Air Quality Control Region. The Southeast Florida Intrastate Air Quality Control Region is redesignated to consist of the territorial...

  9. 40 CFR 81.62 - Northeast Mississippi Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.62 Northeast Mississippi Intrastate Air Quality Control Region. The Alabama-Mississippi-Tennessee Interstate Air Quality Control Region has been renamed the...

  10. 40 CFR 81.24 - Niagara Frontier Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.24 Niagara Frontier Intrastate Air Quality Control Region. The Niagara Frontier Intrastate Air Quality Control Region (New York) consists of the territorial...

  11. 40 CFR 81.28 - Metropolitan Baltimore Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.28 Metropolitan Baltimore Intrastate Air Quality Control Region. The Metropolitan Baltimore Intrastate Air Quality Control Region (Maryland) consists of the territorial...

  12. 40 CFR 81.34 - Metropolitan Dayton Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.34 Metropolitan Dayton Intrastate Air Quality Control Region. The Metropolitan Dayton Intrastate Air Quality Control Region consists of the territorial area encompassed by...

  13. 40 CFR 81.47 - Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.47 Central Oklahoma Intrastate Air Quality Control Region. The Metropolitan Oklahoma Intrastate Air Quality Control Region has been renamed the Central Oklahoma...

  14. 40 CFR 81.14 - Metropolitan Chicago Interstate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.14 Metropolitan Chicago Interstate Air Quality Control Region. The Metropolitan Chicago Interstate Air Quality Control Region (Illinois-Indiana) is revised to consist of...

  15. 40 CFR 81.19 - Metropolitan Boston Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.19 Metropolitan Boston Intrastate Air Quality Control Region. The Metropolitan Boston Intrastate Air Quality Control Region (Massachusetts) consists of the territorial...

  16. 40 CFR 81.59 - Cumberland-Keyser Interstate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.59 Cumberland-Keyser Interstate Air Quality Control Region. The Cumberland-Keyser Interstate Air Quality Control Region (Maryland-West Virginia) has been revised to...

  17. 40 CFR 81.75 - Metropolitan Charlotte Interstate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.75 Metropolitan Charlotte Interstate Air Quality Control Region. The Metropolitan Charlotte Interstate Air Quality Control Region (North Carolina-South Carolina) has been...

  18. 40 CFR 81.44 - Metropolitan Memphis Interstate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.44 Metropolitan Memphis Interstate Air Quality Control Region. The Metropolitan Memphis Interstate Air Quality Control Region (Arkansas-Mississippi-Tennessee) consists of...

  19. 40 CFR 81.31 - Metropolitan Providence Interstate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.31 Metropolitan Providence Interstate Air Quality Control Region. The Metropolitan Providence Interstate Air Quality Control Region (Rhode Island-Massachusetts) consists of...

  20. 40 CFR 81.14 - Metropolitan Chicago Interstate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.14 Metropolitan Chicago Interstate Air Quality Control Region. The Metropolitan Chicago Interstate Air Quality Control Region (Illinois-Indiana) is revised to consist of...