Science.gov

Sample records for air limited type

  1. 75 FR 43092 - Airworthiness Directives; Viking Air Limited (Type Certificate Previously Held by Bombardier, Inc...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ..., Flammability Reduction and Maintenance and Inspection Requirements'' (66 FR 23086, May 7, 2001). In addition to...; 2. Is not a ``significant rule''under the DOT Regulatory Policies and Procedures (44 FR 11034... Directives; Viking Air Limited (Type Certificate Previously Held by Bombardier, Inc.) Model DHC-7...

  2. 76 FR 34011 - Airworthiness Directives; Viking Air Limited (Type Certificate No. A-815 Formerly Held by...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-10

    ... 2011-05-02, Amendment 39-16611 (76 FR 10220, February 24, 2011), for certain Viking Air Limited (Type...-05-02, Amendment 39-16611 (76 FR 10220, February 24, 2011), and adding the following new AD: Viking... a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February...

  3. 76 FR 10220 - Airworthiness Directives; Viking Air Limited (Type Certificate No. A-815 Formerly Held by...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-24

    ... ] December 7, 2010 (75 FR 75932). That NPRM proposed to require repetitively inspecting the elevator control... Order 12866, (2) Is not a ``significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034...-020-AD; Amendment 39-16611; AD 2011-05-02] RIN 2120-AA64 Airworthiness Directives; Viking Air...

  4. 14 CFR 93.319 - Commercial air tour limitations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Commercial air tour limitations. 93.319... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES Special Flight Rules in the Vicinity of Grand Canyon National Park, AZ § 93.319 Commercial air tour limitations. (a) Unless...

  5. 14 CFR 93.319 - Commercial air tour limitations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Commercial air tour limitations. 93.319... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES Special Flight Rules in the Vicinity of Grand Canyon National Park, AZ § 93.319 Commercial air tour limitations. (a) Unless...

  6. 14 CFR 93.319 - Commercial air tour limitations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Commercial air tour limitations. 93.319 Section 93.319 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES Special Flight Rules in the Vicinity of Grand Canyon National Park, AZ...

  7. 30 CFR 57.13010 - Reciprocating-type air compressors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Reciprocating-type air compressors. 57.13010... Air and Boilers § 57.13010 Reciprocating-type air compressors. (a) Reciprocating-type air compressors... than 25 percent. (b) However, this standard does not apply to reciprocating-type air compressors...

  8. 30 CFR 57.13010 - Reciprocating-type air compressors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Reciprocating-type air compressors. 57.13010... Air and Boilers § 57.13010 Reciprocating-type air compressors. (a) Reciprocating-type air compressors... than 25 percent. (b) However, this standard does not apply to reciprocating-type air compressors...

  9. 14 CFR 93.319 - Commercial air tour limitations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Vicinity of Grand Canyon National Park, AZ § 93.319 Commercial air tour limitations. (a) Unless excepted... 119 for part 121 or 135 operations may conduct more commercial air tours in the Grand Canyon National... conformance with the routes and airspace authorizations as specified in its Grand Canyon National Park...

  10. 14 CFR 93.319 - Commercial air tour limitations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Vicinity of Grand Canyon National Park, AZ § 93.319 Commercial air tour limitations. (a) Unless excepted... 119 for part 121 or 135 operations may conduct more commercial air tours in the Grand Canyon National... conformance with the routes and airspace authorizations as specified in its Grand Canyon National Park...

  11. 30 CFR 56.13010 - Reciprocating-type air compressors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Reciprocating-type air compressors. 56.13010... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13010 Reciprocating-type air compressors. (a) Reciprocating-type air...

  12. 30 CFR 56.13010 - Reciprocating-type air compressors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Reciprocating-type air compressors. 56.13010... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13010 Reciprocating-type air compressors. (a) Reciprocating-type air...

  13. 30 CFR 56.13010 - Reciprocating-type air compressors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Reciprocating-type air compressors. 56.13010... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13010 Reciprocating-type air compressors. (a) Reciprocating-type air...

  14. Stability limit of room air temperature of a VAV system

    SciTech Connect

    Matsuba, Tadahiko; Kamimura, Kazuyuki; Kasahara, Masato; Kimbara, Akiomi; Kurosu, Shigeru; Murasawa, Itaru; Hashimoto, Yukihiko

    1998-12-31

    To control heating, ventilating, and air-conditioning (HVAC) systems, it has been necessary to accept an analog system controlled mainly by proportional-plus-integral-plus-derivative (PID) action. However, when conventional PID controllers are replaced with new digital controllers by selecting the same PID parameters as before, the control loops have often got into hunting phenomena, which result in undamped oscillations. Unstable control characteristics (such as huntings) are thought to be one of the crucial problems faced by field operators. The PID parameters must be carefully selected to avoid instabilities. In this study, a room space is simulated as a thermal system that is air-conditioned by a variable-air-volume (VAV) control system. A dynamic room model without infiltration or exfiltration, which is directly connected to a simple air-handling unit without an economizer, is developed. To explore the possible existence of huntings, a numerical system model is formulated as a bilinear system with time-delayed feedback, and a parametric analysis of the stability limit is presented. Results are given showing the stability region affected by the selection of control and system parameters. This analysis was conducted to help us tune the PID controllers for optimal HVAC control.

  15. Computational Modeling of Transport Limitations in Li-Air Batteries

    SciTech Connect

    Ryan, Emily M.; Ferris, Kim F.; Tartakovsky, Alexandre M.; Khaleel, Mohammad A.

    2013-02-22

    In this paper we investigate transport limitations in the electrodes of lithium-air batteries through computational modeling. We use meso-scale models to consider the effects of dendrites on the current and potential at the anode surface, and to investigate the effects of reaction and transport parameters on the formation of precipitates in the cathode. The formation of dendrites on the anode surface during cycling reduces the transport of ions and can lead to short circuits in the cell. Growth of precipitates in the cathode reduces the specific capacity of the cell due to surface passivation and pore clogging. Both of these degradation mechanisms depend on meso-scale phenomena, such as the pore-scale reactive transport in the cathode. To understand the effects of the meso-scale transport and precipitation on the performance and lifetime of Li-air batteries, meso-scale modeling is needed that is able to resolve the electrodes and their microstructures.

  16. Limitation of discharge capacity and mechanisms of air-electrode deactivation in silicon-air batteries.

    PubMed

    Jakes, Peter; Cohn, Gil; Ein-Eli, Yair; Scheiba, Frieder; Ehrenberg, Helmut; Eichel, Rüdiger-A

    2012-11-01

    The electrocatalytical process at the air cathode in novel silicon-air batteries using the room-temperature ionic liquid hydrophilic 1-ethyl-3-methylimidazolium oligofluorohydrogenate [EMI⋅2.3 HF⋅F] as electrolyte and highly doped silicon wafers as anodes is investigated by electrochemical means, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) spectroscopy. The results obtained by XPS and EPR provide a model to describe the limited discharge capacity by means of a mechanism of air-electrode deactivation. In that respect, upon discharge the silicon-air battery's cathode is not only blocked by silicon oxide reduction products, but also experiences a major modification in the MnO₂ catalyst nature. The proposed modification of the MnO₂ catalyst by means of a MnF₂ surface layer greatly impacts the Si-air performance and describes a mechanism relevant for other metal-air batteries, such as the lithium-air. Moreover, the ability for this deactivation layer to form is greatly impacted by water in the electrolyte. PMID:23033259

  17. Air blast type coal slurry fuel injector

    DOEpatents

    Phatak, Ramkrishna G.

    1986-01-01

    A device to atomize and inject a coal slurry in the combustion chamber of an internal combustion engine, and which eliminates the use of a conventional fuel injection pump/nozzle. The injector involves the use of compressed air to atomize and inject the coal slurry and like fuels. In one embodiment, the breaking and atomization of the fuel is achieved with the help of perforated discs and compressed air. In another embodiment, a cone shaped aspirator is used to achieve the breaking and atomization of the fuel. The compressed air protects critical bearing areas of the injector.

  18. Air blast type coal slurry fuel injector

    DOEpatents

    Phatak, R.G.

    1984-08-31

    A device to atomize and inject a coal slurry in the combustion chamber of an internal combustion engine is disclosed which eliminates the use of a conventional fuel injection pump/nozzle. The injector involves the use of compressed air to atomize and inject the coal slurry and like fuels. In one embodiment, the breaking and atomization of the fuel is achieved with the help of perforated discs and compressed air. In another embodiment, a cone shaped aspirator is used to achieve the breaking and atomization of the fuel. The compressed air protects critical bearing areas of the injector.

  19. 46 CFR Appendix A to Part 197 - Air No-Decompression Limits

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Air No-Decompression Limits A Appendix A to Part 197... STANDARDS GENERAL PROVISIONS Pt. 197, App. A Appendix A to Part 197—Air No-Decompression Limits The following table gives the depth versus bottom time limits for single, no-decompression, air dives...

  20. 46 CFR Appendix A to Part 197 - Air No-Decompression Limits

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Air No-Decompression Limits A Appendix A to Part 197... STANDARDS GENERAL PROVISIONS Pt. 197, App. A Appendix A to Part 197—Air No-Decompression Limits The following table gives the depth versus bottom time limits for single, no-decompression, air dives...

  1. Travel Air commercial airplane -- Type 5000

    NASA Technical Reports Server (NTRS)

    1927-01-01

    The 5000 is a semicantilever monoplane, closed cabin type, with pilot about in line with the leading edge of the wing and room for 4 passengers behind him. It is equipped with a Wright Whirlwind engine.

  2. 42 CFR 84.142 - Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators; minimum requirements. 84.142 Section 84.142 Public....142 Air supply source; hand-operated or motor driven air blowers; Type A supplied-air...

  3. 42 CFR 84.142 - Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators; minimum requirements. 84.142 Section 84.142 Public....142 Air supply source; hand-operated or motor driven air blowers; Type A supplied-air...

  4. 42 CFR 84.142 - Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators; minimum requirements. 84.142 Section 84.142 Public....142 Air supply source; hand-operated or motor driven air blowers; Type A supplied-air...

  5. 42 CFR 84.142 - Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators; minimum requirements. 84.142 Section 84.142 Public....142 Air supply source; hand-operated or motor driven air blowers; Type A supplied-air...

  6. Air-stable n-type colloidal quantum dot solids.

    PubMed

    Ning, Zhijun; Voznyy, Oleksandr; Pan, Jun; Hoogland, Sjoerd; Adinolfi, Valerio; Xu, Jixian; Li, Min; Kirmani, Ahmad R; Sun, Jon-Paul; Minor, James; Kemp, Kyle W; Dong, Haopeng; Rollny, Lisa; Labelle, André; Carey, Graham; Sutherland, Brandon; Hill, Ian; Amassian, Aram; Liu, Huan; Tang, Jiang; Bakr, Osman M; Sargent, Edward H

    2014-08-01

    Colloidal quantum dots (CQDs) offer promise in flexible electronics, light sensing and energy conversion. These applications rely on rectifying junctions that require the creation of high-quality CQD solids that are controllably n-type (electron-rich) or p-type (hole-rich). Unfortunately, n-type semiconductors made using soft matter are notoriously prone to oxidation within minutes of air exposure. Here we report high-performance, air-stable n-type CQD solids. Using density functional theory we identify inorganic passivants that bind strongly to the CQD surface and repel oxidative attack. A materials processing strategy that wards off strong protic attack by polar solvents enabled the synthesis of an air-stable n-type PbS CQD solid. This material was used to build an air-processed inverted quantum junction device, which shows the highest current density from any CQD solar cell and a solar power conversion efficiency as high as 8%. We also feature the n-type CQD solid in the rapid, sensitive, and specific detection of atmospheric NO2. This work paves the way for new families of electronic devices that leverage air-stable quantum-tuned materials. PMID:24907929

  7. 14 CFR 330.9 - What are the limits on compensation to air carriers?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false What are the limits on compensation to air... (AVIATION PROCEEDINGS) PROCEDURAL REGULATIONS PROCEDURES FOR COMPENSATION OF AIR CARRIERS General Provisions § 330.9 What are the limits on compensation to air carriers? (a) You are eligible to...

  8. 46 CFR Appendix A to Part 197 - Air No-Decompression Limits

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Air No-Decompression Limits A Appendix A to Part 197... STANDARDS GENERAL PROVISIONS Pt. 197, App. A Appendix A to Part 197—Air No-Decompression Limits The... within any 12-hour period. The limit is the maximum bottom time in minutes that a diver can spend at...

  9. 46 CFR Appendix A to Part 197 - Air No-Decompression Limits

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Air No-Decompression Limits A Appendix A to Part 197... STANDARDS GENERAL PROVISIONS Pt. 197, App. A Appendix A to Part 197—Air No-Decompression Limits The... within any 12-hour period. The limit is the maximum bottom time in minutes that a diver can spend at...

  10. Air Pollution as a Risk Factor for Type 2 Diabetes

    PubMed Central

    Rao, Xiaoquan; Patel, Priti; Puett, Robin; Rajagopalan, Sanjay

    2015-01-01

    Recent studies in both humans and animals suggest that air pollution is an important risk factor for type 2 diabetes mellitus (T2DM). However, the mechanism by which air pollution mediates propensity to diabetes is not fully understood. While a number of epidemiologic studies have shown a positive association between ambient air pollution exposure and risk for T2DM, some studies have not found such a relationship. Experimental studies in susceptible disease models do support this association and suggest the involvement of tissues involved in the pathogenesis of T2DM such as the immune system, adipose, liver, and central nervous system. This review summarizes the epidemiologic and experimental evidence between ambient outdoor air pollution and T2DM. PMID:25628401

  11. 14 CFR 121.161 - Airplane limitations: Type of route.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Airplane limitations: Type of route. 121... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.161 Airplane... specifications, no certificate holder may operate a turbine-engine-powered airplane over a route that contains...

  12. 14 CFR 121.161 - Airplane limitations: Type of route.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Airplane limitations: Type of route. 121... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.161 Airplane... specifications, no certificate holder may operate a turbine-engine-powered airplane over a route that contains...

  13. 14 CFR 121.161 - Airplane limitations: Type of route.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Airplane limitations: Type of route. 121... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.161 Airplane... specifications, no certificate holder may operate a turbine-engine-powered airplane over a route that contains...

  14. 14 CFR 121.161 - Airplane limitations: Type of route.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airplane limitations: Type of route. 121... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.161 Airplane... specifications, no certificate holder may operate a turbine-engine-powered airplane over a route that contains...

  15. A theoretical study of limit cycle oscillations of plenum air cushions

    NASA Astrophysics Data System (ADS)

    Hinchey, M. J.; Sullivan, P. A.

    1981-11-01

    Air cushion vehicles (ACV) are prone to the occurrence of dynamic instabilities which frequently appear as stable finite amplitude oscillations. The aim of this work is to ascertain if the non-linearities characteristics of ACV dynamics generate limit cycle oscillations for cushion systems operating at conditions for which a linear theory predicts instability. The types of non-linearity that can occur are discussed, and an analysis is presented for a single cell flexible skirted plenum chamber constrained to move in pure heave only. Two cushion feed cases are considered: a plenum box supply and a duct. The results obtained by a Galerkin/describing function analysis are compared with those generated by a full numerical simulation. For the plenum box supply system, it is shown that the limit cycles can be suppressed by using a piston to introduce high frequency small amplitude volume oscillations into the plenum chamber.

  16. 32 CFR 644.415 - Army military and Air Force lands-$50,000 limitation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 4 2012-07-01 2011-07-01 true Army military and Air Force lands-$50,000 limitation. 644.415 Section 644.415 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY... Interests § 644.415 Army military and Air Force lands—$50,000 limitation. (a) 10 U.S.C. 2672 authorizes...

  17. 32 CFR 644.415 - Army military and Air Force lands-$50,000 limitation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 4 2013-07-01 2013-07-01 false Army military and Air Force lands-$50,000 limitation. 644.415 Section 644.415 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY... Interests § 644.415 Army military and Air Force lands—$50,000 limitation. (a) 10 U.S.C. 2672 authorizes...

  18. 32 CFR 644.415 - Army military and Air Force lands-$50,000 limitation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 4 2014-07-01 2013-07-01 true Army military and Air Force lands-$50,000 limitation. 644.415 Section 644.415 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY... Interests § 644.415 Army military and Air Force lands—$50,000 limitation. (a) 10 U.S.C. 2672 authorizes...

  19. 32 CFR 644.415 - Army military and Air Force lands-$50,000 limitation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Army military and Air Force lands-$50,000 limitation. 644.415 Section 644.415 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY... Interests § 644.415 Army military and Air Force lands—$50,000 limitation. (a) 10 U.S.C. 2672 authorizes...

  20. 32 CFR 644.415 - Army military and Air Force lands-$50,000 limitation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Army military and Air Force lands-$50,000 limitation. 644.415 Section 644.415 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY... Interests § 644.415 Army military and Air Force lands—$50,000 limitation. (a) 10 U.S.C. 2672 authorizes...

  1. Identifying an indoor air exposure limit for formaldehyde considering both irritation and cancer hazards

    PubMed Central

    Golden, Robert

    2011-01-01

    Formaldehyde is a well-studied chemical and effects from inhalation exposures have been extensively characterized in numerous controlled studies with human volunteers, including asthmatics and other sensitive individuals, which provide a rich database on exposure concentrations that can reliably produce the symptoms of sensory irritation. Although individuals can differ in their sensitivity to odor and eye irritation, the majority of authoritative reviews of the formaldehyde literature have concluded that an air concentration of 0.3 ppm will provide protection from eye irritation for virtually everyone. A weight of evidence-based formaldehyde exposure limit of 0.1 ppm (100 ppb) is recommended as an indoor air level for all individuals for odor detection and sensory irritation. It has recently been suggested by the International Agency for Research on Cancer (IARC), the National Toxicology Program (NTP), and the US Environmental Protection Agency (US EPA) that formaldehyde is causally associated with nasopharyngeal cancer (NPC) and leukemia. This has led US EPA to conclude that irritation is not the most sensitive toxic endpoint and that carcinogenicity should dictate how to establish exposure limits for formaldehyde. In this review, a number of lines of reasoning and substantial scientific evidence are described and discussed, which leads to a conclusion that neither point of contact nor systemic effects of any type, including NPC or leukemia, are causally associated with exposure to formaldehyde. This conclusion supports the view that the equivocal epidemiology studies that suggest otherwise are almost certainly flawed by identified or yet to be unidentified confounding variables. Thus, this assessment concludes that a formaldehyde indoor air limit of 0.1 ppm should protect even particularly susceptible individuals from both irritation effects and any potential cancer hazard. PMID:21635194

  2. Development of an Air Transport Type A Fissile Package

    SciTech Connect

    Blanton, P.; Ebert, K.

    2011-07-13

    This paper presents the summary of testing by the Savannah River National Laboratory (SRNL) to support development of a light weight (<140 lbs) air transport qualified Type A Fissile Packaging. The package design incorporates features and materials specifically designed to minimize packaging weight. The light weight package is being designed to provide confinement to the contents when subjected to the normal and hypothetical conditions required of an air transportable Type A Fissile radioactive material shipping package. The objective of these tests was to provide design input to the final design for the LORX Type A Fissile Air Transport Packaging when subjected to the performance requirements of the drop, crush and puncture probe test of 10CFR71. The post test evaluation of the prototype packages indicates that all of the tested designs would satisfactorily confine the content within the packaging. The differences in the performance of the prototypes varied significantly depending on the core materials and their relative densities. Information gathered from these tests is being used to develop the final design for the Department of Homeland Security.

  3. 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...

  4. 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 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...

  5. Diatom attachment inhibition: limiting surface accessibility through air entrapment.

    PubMed

    Wu, Alex H-F; Nakanishi, Kenichi; Cho, K L; Lamb, Robert

    2013-12-01

    Surfaces consisting of sub micron holes (0.420-0.765 μm) engineered into nanoparticle (12 nm) coatings were examined for marine antifouling behaviour that defines early stage settlement. Immersed surfaces were found to be resistant to a 5-hour attachment assay of Amphora coffeaeformis, a marine organism commonly found in abundance on fouled substrates such as foul-releasing paints and self-polishing coatings. Attachment inhibition was attributed to the accessibility of diatoms to the surface. This was governed by the size and morphology of trapped interfacial air pockets measured in-situ using synchrotron small angle x-ray scattering. Surfaces containing larger pores (0.765 μm) exhibited the highest resistance. Macroscopic wettability via contact angle measurements however remained at 160° and sliding angle of < 5° and was found to be independent of pore size and not indicative of early stage fouling behaviour. The balance of hierarchical nano/micro length scales was critical in defining the early stage stability of biofouling character of the interface. PMID:24706117

  6. Compressive fatigue limit of four types of dental restorative materials.

    PubMed

    Chen, Song; Öhman, Caroline; Jefferies, Steven R; Gray, Holly; Xia, Wei; Engqvist, Håkan

    2016-08-01

    The purpose of this study was to evaluate the quasi-static compressive strength and the compressive fatigue limit of four different dental restorative materials, before and after aging in distilled water for 30 days. A conventional glass ionomer cement (Fuji IX GP; IG), a zinc-reinforced glass ionomer cement (Chemfil rock; CF), a light curable resin-reinforced glass ionomer cement (Fuji II LC; LC) and a resin-based composite (Quixfil; QF) were investigated. Cylindrical specimens (4mm in diameter and 6mm in height) were prepared according to the manufacturer׳s instructions. The compressive fatigue limit was obtained using the staircase method. Samples were tested in distilled water at 37°C, at a frequency of 10Hz with 10(5) cycles set as run-out. 17 fatigue samples were tested for each group. Two-way ANOVA and one-way ANOVA followed by Tukey׳s post-hoc test were used to analyze the results. Among the four types of materials, the resin-based composite exhibited the highest compressive strength (244±13.0MPa) and compressive fatigue limit (134±7.8MPa), followed by the light-cured resin reinforced glass ionomer cement (168±8.5MPa and 92±6.6MPa, respectively) after one day of storage in distilled water. After being stored for 30 days, all specimens showed an increase in compressive strength. Aging showed no effect on the compressive fatigue limit of the resin-based composite and the light-cured resin reinforced glass ionomer cement, however, the conventional glass ionomer cements showed a drastic decrease (37% for IG, 31% for CF) in compressive fatigue limit. In conclusion, in the present study, resin modified GIC and resin-based composite were found to have superior mechanical properties to conventional GIC. PMID:27085845

  7. A novel type N coaxial air-line verification standard

    NASA Astrophysics Data System (ADS)

    Shoaib, N.; Kuhlmann, K.; Judaschke, R.

    2015-04-01

    In this paper, the design and analysis of a novel coaxial type N verification standard based on an air-line is presented. The measurement uncertainty budget is computed by taking into account the mechanical and dielectric tolerances, thus allowing the determination of the transmission loss uncertainties of the verification standard. The calculated results are obtained by using commercially available electromagnetic software. The data analysis is carried out for complex-valued quantities. The measurement uncertainty due to different error sources is computed according to the Law of Propagation of Uncertainty. Simulated and experimental results are compared to demonstrate the applicability of the approach.

  8. 42 CFR 84.154 - Airflow resistance test; Type B and Type BE supplied-air respirators; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Airflow resistance test; Type B and Type BE... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.154 Airflow resistance test; Type B and Type BE supplied-air respirators; minimum requirements. (a) Airflow resistance shall...

  9. 42 CFR 84.154 - Airflow resistance test; Type B and Type BE supplied-air respirators; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Airflow resistance test; Type B and Type BE... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.154 Airflow resistance test; Type B and Type BE supplied-air respirators; minimum requirements. (a) Airflow resistance shall...

  10. 42 CFR 84.153 - Airflow resistance test, Type A and Type AE supplied-air respirators; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Airflow resistance test, Type A and Type AE... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.153 Airflow resistance test, Type A and Type AE supplied-air respirators; minimum requirements. (a) Airflow resistance will...

  11. 42 CFR 84.154 - Airflow resistance test; Type B and Type BE supplied-air respirators; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Airflow resistance test; Type B and Type BE... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.154 Airflow resistance test; Type B and Type BE supplied-air respirators; minimum requirements. (a) Airflow resistance shall...

  12. 42 CFR 84.153 - Airflow resistance test, Type A and Type AE supplied-air respirators; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Airflow resistance test, Type A and Type AE... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.153 Airflow resistance test, Type A and Type AE supplied-air respirators; minimum requirements. (a) Airflow resistance will...

  13. 42 CFR 84.153 - Airflow resistance test, Type A and Type AE supplied-air respirators; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Airflow resistance test, Type A and Type AE... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.153 Airflow resistance test, Type A and Type AE supplied-air respirators; minimum requirements. (a) Airflow resistance will...

  14. 42 CFR 84.154 - Airflow resistance test; Type B and Type BE supplied-air respirators; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Airflow resistance test; Type B and Type BE... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.154 Airflow resistance test; Type B and Type BE supplied-air respirators; minimum requirements. (a) Airflow resistance shall...

  15. 42 CFR 84.153 - Airflow resistance test, Type A and Type AE supplied-air respirators; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Airflow resistance test, Type A and Type AE... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.153 Airflow resistance test, Type A and Type AE supplied-air respirators; minimum requirements. (a) Airflow resistance will...

  16. Synoptic typing and its application to the investigation of weather - air pollution relationships in Kuwait

    NASA Astrophysics Data System (ADS)

    Al-Shatti, A.; Phillips, I. D.; Baker, J.

    2009-04-01

    Principal components analysis and cluster analysis of surface meteorological data were used to derive the different air mass types for Kuwait. The air mass types were analysed in terms of their mean meteorological and associated weather chart characteristics in order to relate them to their different synoptic situations. The air mass types were subsequently analysed with air pollutant concentration data. Here we report on the identified air mass types, their seasonal dependence and their pollution characteristics. Analysis of the air mass types according to pollutant mean and extreme values helps to identify the different meteorological and transport conditions influencing pollution in this region.

  17. Type 0 open string amplitudes and the tensionless limit

    NASA Astrophysics Data System (ADS)

    Rojas, Francisco

    2014-12-01

    The sum over planar multiloop diagrams in the NS + sector of type 0 open strings in flat spacetime has been proposed by Thorn as a candidate to resolve nonperturbative issues of gauge theories in the large N limit. With S U (N ) Chan-Paton factors, the sum over planar open string multiloop diagrams describes the 't Hooft limit N →∞ with N gs2 held fixed. By including only planar diagrams in the sum the usual mechanism for the cancellation of loop divergences (which occurs, for example, among the planar and Möbius strip diagrams by choosing a specific gauge group) is not available and a renormalization procedure is needed. In this article the renormalization is achieved by suspending total momentum conservation by an amount p ≡∑ i n ki≠0 at the level of the integrands in the integrals over the moduli and analytically continuing them to p =0 at the very end. This procedure has been successfully tested for the 2 and 3 gluon planar loop amplitudes by Thorn. Gauge invariance is respected and the correct running of the coupling in the limiting gauge field theory was also correctly obtained. In this article we extend those results in two directions. First, we generalize the renormalization method to an arbitrary n -gluon planar loop amplitude giving full details for the 4-point case. One of our main results is to provide a fully renormalized amplitude which is free of both UV and the usual spurious divergences leaving only the physical singularities in it. Second, using the complete renormalized amplitude, we extract the high-energy scattering regime at fixed angle (tensionless limit). Apart from obtaining the usual exponential falloff at high energies, we compute the full dependence on the scattering angle which shows the existence of a smooth connection between the Regge and hard scattering regimes.

  18. A new circulation type classification based upon Lagrangian air trajectories

    NASA Astrophysics Data System (ADS)

    Ramos, Alexandre; Sprenger, Michael; Wernli, Heini; Durán-Quesada, Ana María; Lorenzo, Maria Nieves; Gimeno, Luis

    2014-10-01

    A new classification method of the large-scale circulation characteristic for a specific target area (NW Iberian Peninsula) is presented, based on the analysis of 90-h backward trajectories arriving in this area calculated with the 3-D Lagrangian particle dispersion model FLEXPART. A cluster analysis is applied to separate the backward trajectories in up to five representative air streams for each day. Specific measures are then used to characterise the distinct air streams (e.g., curvature of the trajectories, cyclonic or anticyclonic flow, moisture evolution, origin and length of the trajectories). The robustness of the presented method is demonstrated in comparison with the Eulerian Lamb weather type classification. A case study of the 2003 heatwave is discussed in terms of the new Lagrangian circulation and the Lamb weather type classifications. It is shown that the new classification method adds valuable information about the pertinent meteorological conditions, which are missing in an Eulerian approach. The new method is climatologically evaluated for the five-year time period from December 1999 to November 2004. The ability of the method to capture the inter-seasonal circulation variability in the target region is shown. Furthermore, the multi-dimensional character of the classification is shortly discussed, in particular with respect to inter-seasonal differences. Finally, the relationship between the new Lagrangian classification and the precipitation in the target area is studied.

  19. 42 CFR 84.147 - Type B supplied-air respirator; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Type B supplied-air respirator; minimum... SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.147 Type B supplied-air respirator; minimum requirements. No Type...

  20. Effect of limited air exposure and comparative performance between thermophilic and mesophilic solid-state anaerobic digestion of switchgrass.

    PubMed

    Sheets, Johnathon P; Ge, Xumeng; Li, Yebo

    2015-03-01

    Switchgrass is an attractive feedstock for biogas production via anaerobic digestion (AD). Many studies have used switchgrass for liquid anaerobic digestion (L-AD), but few have used switchgrass for solid-state anaerobic digestion (SS-AD). Limited air exposure to the reactor headspace has been adopted in commercial scale anaerobic digesters for different applications. However, little research has examined the effect of limited air exposure on biogas production during SS-AD. In this study, the effects of air exposure and total solids (TS) content on SS-AD performance were evaluated under mesophilic (36±1°C) and thermophilic (55±0.3°C) conditions. Limited air exposure did not significantly influence the methane yield during SS-AD. Thermophilic SS-AD had greater methane yields (102-145LCH4kg(-1)VSadded) than mesophilic SS-AD (88-113LCH4kg(-1)VSadded). Both mesophilic SS-AD (73-136GJ) and thermophilic SS-AD (2-95GJ) produced positive net energy based on a theoretical 'garage-type' SS-AD digester operating in a temperate climate. PMID:25618499

  1. TYPE A FISSILE PACKAGING FOR AIR TRANSPORT PROJECT OVERVIEW

    SciTech Connect

    Eberl, K.; Blanton, P.

    2013-10-11

    This paper presents the project status of the Model 9980, a new Type A fissile packaging for use in air transport. The Savannah River National Laboratory (SRNL) developed this new packaging to be a light weight (<150-lb), drum-style package and prepared a Safety Analysis for Packaging (SARP) for submission to the DOE/EM. The package design incorporates unique features and engineered materials specifically designed to minimize packaging weight and to be in compliance with 10CFR71 requirements. Prototypes were fabricated and tested to evaluate the design when subjected to Normal Conditions of Transport (NCT) and Hypothetical Accident Conditions (HAC). An overview of the design details, results of the regulatory testing, and lessons learned from the prototype fabrication for the 9980 will be presented.

  2. 42 CFR 84.142 - Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators; minimum requirements. 84.142 Section 84.142 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL...

  3. 7 CFR 30.38 - Class 3; air-cured types and groups.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... produced principally in the Green River section of Kentucky. (g) Type 37. That type of air-cured or sun-cured tobacco commonly known as Virginia Sun-cured, Virginia Sun and Air-cured, or Dark Air-cured...

  4. 7 CFR 30.38 - Class 3; air-cured types and groups.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... produced principally in the Green River section of Kentucky. (g) Type 37. That type of air-cured or sun-cured tobacco commonly known as Virginia Sun-cured, Virginia Sun and Air-cured, or Dark Air-cured...

  5. 7 CFR 30.38 - Class 3; air-cured types and groups.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... produced principally in the Green River section of Kentucky. (g) Type 37. That type of air-cured or sun-cured tobacco commonly known as Virginia Sun-cured, Virginia Sun and Air-cured, or Dark Air-cured...

  6. 7 CFR 30.38 - Class 3; air-cured types and groups.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... produced principally in the Green River section of Kentucky. (g) Type 37. That type of air-cured or sun-cured tobacco commonly known as Virginia Sun-cured, Virginia Sun and Air-cured, or Dark Air-cured...

  7. 42 CFR 84.148 - Type C supplied-air respirator, continuous flow class; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.148 Type C supplied-air respirator, continuous... pressure at any point in the supply system exceeds 863 kN/m.2 (125 pounds per square inch gage),...

  8. 42 CFR 84.148 - Type C supplied-air respirator, continuous flow class; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.148 Type C supplied-air respirator, continuous... pressure at any point in the supply system exceeds 863 kN/m.2 (125 pounds per square inch gage),...

  9. 42 CFR 84.148 - Type C supplied-air respirator, continuous flow class; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.148 Type C supplied-air respirator, continuous... pressure at any point in the supply system exceeds 863 kN/m.2 (125 pounds per square inch gage),...

  10. 42 CFR 84.148 - Type C supplied-air respirator, continuous flow class; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.148 Type C supplied-air respirator, continuous... pressure at any point in the supply system exceeds 863 kN/m.2 (125 pounds per square inch gage),...

  11. The upper explosion limit of lower alkanes and alkenes in air at elevated pressures and temperatures.

    PubMed

    Van den Schoor, F; Verplaetsen, F

    2006-01-16

    The upper explosion limit (UEL) of ethane-air, propane-air, n-butane-air, ethylene-air and propylene-air mixtures is determined experimentally at initial pressures up to 30 bar and temperatures up to 250 degrees C. The experiments are performed in a closed spherical vessel with an internal diameter of 200 mm. The mixtures are ignited by fusing a coiled tungsten wire, placed at the centre of the vessel, by electric current. Flame propagation is said to have taken place if there is a pressure rise of at least 1% of the initial pressure after ignition of the mixture. In the pressure-temperature range investigated, a linear dependence of UEL on temperature and a bilinear dependence on pressure are found except in the vicinity of the auto-ignition range. A comparison of the UEL data of the lower alkanes shows that the UEL expressed as equivalence ratio (the actual fuel/air ratio divided by the stoichiometric fuel/air ratio) increases with increasing carbon number in the homologous series of alkanes. PMID:16154265

  12. Experimental study of flammability limits of natural gas-air mixture.

    PubMed

    Liao, S Y; Cheng, Q; Jiang, D M; Gao, J

    2005-03-17

    Flammability limits data are essential for a quantitative risk assessment of explosion hazard associated with the use of combustible gas. The present work is to obtain the fundamental flammability data for prevention of the hazards in the practical applications. Experiments have been conducted in a constant volume combustion bomb, and the fuel considered here is natural gas (NG). The pressure histories in the combustion bomb are recorded and a criterion of 7% pressure rise has been used to judge a flammable mixture. The effects of ethane on NG-air flammability limits have been investigated. By adding diluent (carbon dioxide, nitrogen or their mixture) into NG-air mixture, the dilution effects on the flammability limits have been explored as well, and the results are plotted as functions of diluent ratio. PMID:15752851

  13. Auto-ignition and upper explosion limit of rich propane-air mixtures at elevated pressures.

    PubMed

    Norman, F; Van den Schoor, F; Verplaetsen, F

    2006-09-21

    The auto-ignition limits of propane-air mixtures at elevated pressures up to 15 bar and for concentrations from 10 mol% up to 70 mol% are investigated. The experiments are performed in a closed spherical vessel with a volume of 8 dm3. The auto-ignition temperatures decrease from 300 degrees C to 250 degrees C when increasing the pressure from 1 bar to 14.5 bar. It is shown that the fuel concentration most sensitive to auto-ignition depends on initial pressure. A second series of experiments investigates the upper flammability limit of propane-air mixtures at initial temperatures up to 250 degrees C and pressures up to 30 bar near the auto-ignition area. Finally the propane auto-oxidation is modelled using several detailed kinetic reaction mechanisms and these numerical calculations are compared with the experimental results. PMID:16716499

  14. 40 CFR 60.2971 - What are the emission limitations for air curtain incinerators that burn only wood waste, clean...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2971 Section 60... Lumber, and Yard Waste § 60.2971 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Within 60 days after your air curtain...

  15. 40 CFR 60.1445 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... curtain incinerators that burn 100 percent yard waste? 60.1445 Section 60.1445 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1445 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If your air curtain incinerator...

  16. 40 CFR 60.1445 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... curtain incinerators that burn 100 percent yard waste? 60.1445 Section 60.1445 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1445 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If your air curtain incinerator...

  17. 40 CFR 60.1445 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... curtain incinerators that burn 100 percent yard waste? 60.1445 Section 60.1445 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1445 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If your air curtain incinerator...

  18. 40 CFR 60.1445 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... curtain incinerators that burn 100 percent yard waste? 60.1445 Section 60.1445 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1445 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If your air curtain incinerator...

  19. 40 CFR 60.2971 - What are the emission limitations for air curtain incinerators that burn only wood waste, clean...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2971 Section 60... Lumber, and Yard Waste § 60.2971 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Within 60 days after your air curtain...

  20. 40 CFR 60.1445 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... curtain incinerators that burn 100 percent yard waste? 60.1445 Section 60.1445 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1445 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If your air curtain incinerator...

  1. VLA radio upper limit on Type IIn Supernova 2008S

    NASA Astrophysics Data System (ADS)

    Chandra, Poonam; Soderberg, Alicia

    2008-02-01

    Poonam Chandra and Alicia Soderberg report on behalf of a larger collaboration: We observed type IIn supernova SN 2008S (CBET 1234) with the Very Large Array (VLA) on 2008, February 10.62 UT. We do not detect any radio emission at the supernova position (CBET 1234). The flux density at the supernova position is -62 +/- 36 uJy.

  2. VLA radio upper limit on Type IIn Supernova 2007pk

    NASA Astrophysics Data System (ADS)

    Chandra, Poonam; Soderberg, Alicia

    2007-11-01

    Poonam Chandra and Alicia Soderberg report on behalf of a larger collaboration: We observed Type IIn supernova SN 2007pk (CBET 1129) with the VLA in 8.46 GHz band on 2007, November 12.20 UT, 1.89 days since discovery (CBET 1129). We do not detect radio emission from the SN position (CBET 1129). The flux density at the SN position is 11 +/-26 uJy.

  3. 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 ...

  4. Performance of Desiccant Particle Dispersion Type Air Conditioning System

    NASA Astrophysics Data System (ADS)

    Hatano, Hiroyuki; Suzuki, Koichi; Kojima, Hiromitsu

    An investigation of desiccant air conditioning system is performed to demonstrate its performance in a dispersed desiccant particle systems, based on its higher gas solid contacting efficiency and isothermal dehumidification. Particle dispersion is achieved using the risers of a circulating fluidized bed, CFB, or of a pneumatic conveyer. The risers used for dehumidification are 1390 mm in height and 22 mm in diameter. The former is used to evaluate the overall dehumidification performance and the latter is used to measure the axial humidity distribution under 0.88 m/s of a superficial air velocity. Based on the results of the overall performance by changing solid loading rates, Gs, from 0.4 kg/m2s up to 6 kg/m2s, desiccant particle dispersion shows higher performance in dehumidification, while axial humidity distribution shows very rapid adsorption rate in the entrance zone of the riser. Removal of adsorption heat accelerates dehumidification rate compared to the adiabatic process.

  5. Selection and costing of heat exchangers. Air-cooled type

    NASA Astrophysics Data System (ADS)

    1994-12-01

    ESDU 94043 extends the information in ESDU 92013 which, when an air-cooled exchanger is found appropriate and is costed, provides the results for a datum design 40 ft (12.2 m) long with G-fins and 1 in (25 mm) diameter tube operating at a noise level of 85 dBa. It provides factors derived from an analysis of manufacturer's data to be applied to the cost results from ESDU 92013 to account for variations in those parameters and features. Additional guidance on the configuration and use of air-cooled exchangers is given. The data are incorporated in ESDUpac A9213 which is a Fortran program that implements the selection and costing method of ESDU 92013. It is provided on disc in the software volume compiled to run under DOS with a user-friendly interface that prompts on screen for input data.

  6. Source area identification with observation from limited monitor sites for air pollution episodes in industrial parks

    NASA Astrophysics Data System (ADS)

    Huang, Zihan; Wang, Yuan; Yu, Qi; Ma, Weichun; Zhang, Yan; Chen, Limin

    2015-12-01

    Air pollution episodes of unknown origins are often detected by online equipment for air quality monitoring in industrial parks in China. The number of monitors available to provide observation data, as well as the source information, is often very limited. In such case, the identification of a potential source area is more practical than the precise back-calculation of the real source. The potential source area which can be deduced from the observation data from limited monitors was concerned in this paper. In order to do the source area identification, two inverse methods, a direct method and a statistical sampling method, were applied with a Gaussian puff model as the forward modeling method. The characteristic of the potential source area was illustrated by case studies. Both synthetic and real cases were presented. The distribution of the source locations and its variation with the other unknown source parameters were mainly focused in the case study. As a screening method, source area identification can be applied not only when the number of effective monitors is limited but also when an ideal number of monitors are available as long as the source information is almost uncertain.

  7. Dynamics of flames near the rich-flammability limit of hydrogen-air mixtures

    NASA Technical Reports Server (NTRS)

    Kailasanath, K.; Ganguly, K.; Patnaik, G.

    1993-01-01

    Flames near the rich-flammability limit of hydrogen-air mixtures are studied using a detailed, time-dependent, one-dimensional Lagrangian model. Results from the numerical simulations indicate that a steady burning velocity is not obtained for very rich hydrogen-air mixtures. As the amount of hydrogen is increased, a damped oscillation is observed in the flame and burning velocities, and then, with further increase in the amount of hydrogen, an undamped oscillation with a complex set of frequencies is observed. Simulations with a simplified one-step irreversible chemical reaction do not show these oscillations, suggesting that chemical kinetics plays a strong role in inducing these oscillations. Further analysis shows that the oscillations are due to a competition for H atoms between chain branching and chain-terminating reactions. Simulations of spherically expanding flames suggest that stretch effects (due to curvature) will cause the oscillations to occur in less rich mixtures than that observed for planar flames. The implications of these oscillations on the rich-flammability limit as well as the role of chemical kinetics in creating a fundamental flammability limit is discussed.

  8. Storm type effects on super Clausius-Clapeyron scaling of intense rainstorm properties with air temperature

    NASA Astrophysics Data System (ADS)

    Molnar, P.; Fatichi, S.; Gaál, L.; Szolgay, J.; Burlando, P.

    2015-04-01

    Extreme precipitation is thought to increase with warming at rates similar to or greater than the water vapour holding capacity of the air at ~ 7% °C-1, the so-called Clausius-Clapeyron (CC) rate. We present an empirical study of the variability in the rates of increase in precipitation intensity with air temperature using 30 years of 10 min and 1 h data from 59 stations in Switzerland. The analysis is conducted on storm events rather than fixed interval data, and divided into storm type subsets based on the presence of lightning which is expected to indicate convection. The average rates of increase in extremes (95th percentile) of mean event intensity computed from 10 min data are 6.5% °C-1 (no-lightning events), 8.9% °C-1 (lightning events) and 10.7% °C-1 (all events combined). For peak 10 min intensities during an event the rates are 6.9% °C-1 (no-lightning events), 9.3% °C-1 (lightning events) and 13.0% °C-1 (all events combined). Mixing of the two storm types exaggerates the relations to air temperature. Doubled CC rates reported by other studies are an exception in our data set, even in convective rain. The large spatial variability in scaling rates across Switzerland suggests that both local (orographic) and regional effects limit moisture supply and availability in Alpine environments, especially in mountain valleys. The estimated number of convective events has increased across Switzerland in the last 30 years, with 30% of the stations showing statistically significant changes. The changes in intense convective storms with higher temperatures may be relevant for hydrological risk connected with those events in the future.

  9. 42 CFR 84.154 - Airflow resistance test; Type B and Type BE supplied-air respirators; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Airflow resistance test; Type B and Type BE..., DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.154 Airflow resistance test;...

  10. Ice-type classifications from airborne pulse-limited radar altimeter return waveform characteristics

    NASA Technical Reports Server (NTRS)

    Fedor, L. S.; Hayne, G. S.; Walsh, E. J.

    1989-01-01

    During mid-March 1978, the NASA C-130 aircraft was deployed to Eielson Air Force Base in Fairbanks, Alaska, to make a series of flights over ice in the Beaufort Sea. The radar altimeter data analyzed were obtained northeast of Mackenzie Bay on March 14th in the vicinity of 69.9 deg N, 134.2 deg W. The data were obtained with a 13.9 GHz radar altimeter developed under the NASA Advanced Applications Flight Experiments (AAFE) Program. This airborne radar was built as a forerunner of the Seasat radar altimeter, and utilized the same pulse compression technique. Pulse-limited radar data taken with the altimeter from 1500-m altitude over sea ice are registered to high-quality photography. The backscattered power is statistically related the surface conductivity and to the number of facets whose surface normal is directed towards the radar. The variations of the radar return waveform shape and signal level are correlated with the variation of the ice type determined from photography. The AAFE altimeter has demonstrated that the return waveform shape and signal level of an airborne pulse-limited altimeter at 13.9 GHz respond to sea ice type. The signal level responded dramatically to even a very small fracture in the ice, as long as it occurred directly at the altimeter nadir point. Shear zones and regions of significant compression ridging consistently produced low signal levels. The return waveforms frequently evidenced the characteristics of both specular and diffuse scattering, and there was an indication that the power backscattered at 3 deg off-nadir in a shear zone was actually somewhat higher than that from nadir.

  11. Evaluation of lower flammability limits of fuel-air-diluent mixtures using calculated adiabatic flame temperatures.

    PubMed

    Vidal, M; Wong, W; Rogers, W J; Mannan, M S

    2006-03-17

    The lower flammability limit (LFL) of a fuel is the minimum composition in air over which a flame can propagate. Calculated adiabatic flame temperatures (CAFT) are a powerful tool to estimate the LFL of gas mixtures. Different CAFT values are used for the estimation of LFL. SuperChems is used by industry to perform flammability calculations under different initial conditions which depends on the selection of a threshold temperature. In this work, the CAFT at the LFL is suggested for mixtures of fuel-air and fuel-air-diluents. These CAFT can be used as the threshold values in SuperChems to calculate the LFL. This paper discusses an approach to evaluate the LFL in the presence of diluents such as N2 and CO2 by an algebraic method and by the application of SuperChems using CAFT as the basis of the calculations. The CAFT for different paraffinic and unsaturated hydrocarbons are presented as well as an average value per family of chemicals. PMID:16309829

  12. All-solid-state cable-type flexible zinc-air battery.

    PubMed

    Park, Joohyuk; Park, Minjoon; Nam, Gyutae; Lee, Jang-soo; Cho, Jaephil

    2015-02-25

    A cable-type flexible Zn-air battery with a spiral zinc anode, gel polymer electrolyte (GPE), and air cathode coated on a nonprecious metal catalyst is designed in order to extend its application area toward wearable electronic devices. PMID:25532853

  13. New type of capillary for use as ion beam collimator and air-vacuum interface

    NASA Astrophysics Data System (ADS)

    Stoytschew, V.; Schulte-Borchers, M.; Božičević Mihalića, Iva; Perez, R. D.

    2016-08-01

    Glass capillaries offer a unique way to combine small diameter ion beam collimation with an air-vacuum interface for ambient pressure ion beam applications. Usually they have an opening diameter of a few microns, limiting the air inflow sufficiently to maintain stable conditions on the vacuum side. As the glass capillaries generally are quite thin and fragile, handling of the capillary in the experiment becomes difficult. They also introduce an X-ray background produced by the capillary wall material, which has to be shielded or subtracted from the data for Particle Induced X-ray Emission (PIXE) applications. To overcome both drawbacks, a new type of conical glass capillary has been developed. It has a higher wall thickness eliminating the low energy X-ray background produced by common capillaries and leading to a more robust lens. The results obtained in first tests show, that this new capillary is suitable for ion beam collimation and encourage further work on the capillary production process to provide thick wall capillaries with an outlet diameter in the single digit micro- or even nanometre range.

  14. 40 CFR 60.3066 - What are the emission limitations for air curtain incinerators that burn only wood waste, clean...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3066 Section 60... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3066 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard...

  15. 40 CFR 60.1920 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... curtain incinerators that burn 100 percent yard waste? 60.1920 Section 60.1920 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1920 What are the emission limits for air curtain incinerators that burn 100 percent yard waste?...

  16. 40 CFR 60.1920 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... curtain incinerators that burn 100 percent yard waste? 60.1920 Section 60.1920 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1920 What are the emission limits for air curtain incinerators that burn 100 percent yard waste?...

  17. 40 CFR 60.3066 - What are the emission limitations for air curtain incinerators that burn only wood waste, clean...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3066 Section 60... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3066 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard...

  18. 40 CFR 60.1920 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... curtain incinerators that burn 100 percent yard waste? 60.1920 Section 60.1920 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1920 What are the emission limits for air curtain incinerators that burn 100 percent yard waste?...

  19. 40 CFR 60.3066 - What are the emission limitations for air curtain incinerators that burn only wood waste, clean...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3066 Section 60... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3066 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard...

  20. 40 CFR 60.1920 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... curtain incinerators that burn 100 percent yard waste? 60.1920 Section 60.1920 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1920 What are the emission limits for air curtain incinerators that burn 100 percent yard waste?...

  1. 40 CFR 60.2971 - What are the emission limitations for air curtain incinerators that burn only wood waste, clean...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2971 Section 60... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2971 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a)...

  2. 40 CFR 62.14815 - What are the emission limitations for air curtain incinerators that burn 100 percent wood wastes...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? 62.14815... Yard Waste § 62.14815 What are the emission limitations for air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? (a) After the date the initial test for opacity...

  3. 40 CFR 62.14815 - What are the emission limitations for air curtain incinerators that burn 100 percent wood wastes...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? 62.14815... Yard Waste § 62.14815 What are the emission limitations for air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? (a) After the date the initial test for opacity...

  4. 40 CFR 60.2971 - What are the emission limitations for air curtain incinerators that burn only wood waste, clean...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2971 Section 60... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2971 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a)...

  5. 40 CFR 60.3066 - What are the emission limitations for air curtain incinerators that burn only wood waste, clean...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3066 Section 60... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3066 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard...

  6. 40 CFR 62.15375 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... curtain incinerators that burn 100 percent yard waste? 62.15375 Section 62.15375 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15375 What are the emission limits for air curtain incinerators that burn 100 percent...

  7. 40 CFR 60.1920 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... curtain incinerators that burn 100 percent yard waste? 60.1920 Section 60.1920 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1920 What are the emission limits for air curtain incinerators that burn 100 percent yard waste?...

  8. 40 CFR 62.14815 - What are the emission limitations for air curtain incinerators that burn 100 percent wood wastes...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? 62.14815... Yard Waste § 62.14815 What are the emission limitations for air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? (a) After the date the initial test for opacity...

  9. 40 CFR 62.15375 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... curtain incinerators that burn 100 percent yard waste? 62.15375 Section 62.15375 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15375 What are the emission limits for air curtain incinerators that burn 100 percent...

  10. 40 CFR 62.15375 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... curtain incinerators that burn 100 percent yard waste? 62.15375 Section 62.15375 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15375 What are the emission limits for air curtain incinerators that burn 100 percent...

  11. 40 CFR 62.15375 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... curtain incinerators that burn 100 percent yard waste? 62.15375 Section 62.15375 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15375 What are the emission limits for air curtain incinerators that burn 100 percent...

  12. 40 CFR 62.14815 - What are the emission limitations for air curtain incinerators that burn 100 percent wood wastes...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? 62.14815... Yard Waste § 62.14815 What are the emission limitations for air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? (a) After the date the initial test for opacity...

  13. 40 CFR 60.3066 - What are the emission limitations for air curtain incinerators that burn only wood waste, clean...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3066 Section 60... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3066 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard...

  14. 40 CFR 62.14815 - What are the emission limitations for air curtain incinerators that burn 100 percent wood wastes...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? 62.14815... Yard Waste § 62.14815 What are the emission limitations for air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? (a) After the date the initial test for opacity...

  15. 40 CFR 60.2971 - What are the emission limitations for air curtain incinerators that burn only wood waste, clean...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2971 Section 60... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2971 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a)...

  16. 40 CFR 62.15375 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... curtain incinerators that burn 100 percent yard waste? 62.15375 Section 62.15375 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15375 What are the emission limits for air curtain incinerators that burn 100 percent...

  17. Analysis of spanwise temperature distribution in three types of air-cooled turbine blade

    NASA Technical Reports Server (NTRS)

    Livingood, John N B; Brown, W Byron

    1950-01-01

    Methods for computing spanwise blade-temperature distributions are derived for air-cooled hollow blades, air-cooled hollow blades with inserts, and air-cooled blades containing internal cooling fins. Individual and combined effects on spanwise blade-temperature distributions of cooling-air and radial heat conduction are determined. In general, the effects of radiation and radial heat conduction were found to be small and the omission of these variations permitted the construction of nondimensional charts for use in determining spanwise temperature distribution through air-cooled turbine blades. An approximate method for determining the allowable stress-limited blade-temperature distribution is included, with brief accounts of a method for determining the maximum allowable effective gas temperatures and the cooling-air requirements. Numerical examples that illustrate the use of the various temperature-distribution equations and of the nondimensional charts are also included.

  18. 40 CFR 60.2250 - What are the emission limitations for air curtain incinerators?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... incinerators? (a) Within 60 days after your air curtain incinerator reaches the charge rate at which it will... for air curtain incinerators? Within 60 days after your air curtain incinerator reaches the...

  19. 14 CFR 93.219 - Allocation of slots for essential air service operations and applicable limitations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... SPECIAL AIR TRAFFIC RULES Allocation of Commuter and Air Carrier IFR Operations at High Density Traffic... or from a High Density Traffic Airport under the Department of Transportation's Essential Air...

  20. 14 CFR 93.219 - Allocation of slots for essential air service operations and applicable limitations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... SPECIAL AIR TRAFFIC RULES Allocation of Commuter and Air Carrier IFR Operations at High Density Traffic... or from a High Density Traffic Airport under the Department of Transportation's Essential Air...

  1. 14 CFR 93.219 - Allocation of slots for essential air service operations and applicable limitations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... SPECIAL AIR TRAFFIC RULES Allocation of Commuter and Air Carrier IFR Operations at High Density Traffic... or from a High Density Traffic Airport under the Department of Transportation's Essential Air...

  2. 14 CFR 93.219 - Allocation of slots for essential air service operations and applicable limitations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... SPECIAL AIR TRAFFIC RULES Allocation of Commuter and Air Carrier IFR Operations at High Density Traffic... or from a High Density Traffic Airport under the Department of Transportation's Essential Air...

  3. 14 CFR 93.219 - Allocation of slots for essential air service operations and applicable limitations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... SPECIAL AIR TRAFFIC RULES Allocation of Commuter and Air Carrier IFR Operations at High Density Traffic... or from a High Density Traffic Airport under the Department of Transportation's Essential Air...

  4. Opposed Jet Burner Extinction Limits: Simple Mixed Hydrocarbon Scramjet Fuels vs Air

    NASA Technical Reports Server (NTRS)

    Pellett, Gerald L.; Vaden, Sarah N.; Wilson, Lloyd G.

    2007-01-01

    Opposed Jet Burner tools have been used extensively by the authors to measure Flame Strength (FS) of laminar non-premixed H2 air and simple hydrocarbon (HC) air counterflow diffusion flames at 1-atm. FS represents a strain-induced extinction limit based on air jet velocity. This paper follows AIAA-2006-5223, and provides new HC air FSs for global testing of chemical kinetics, and for characterizing idealized flameholding potentials during early scramjet-like combustion. Previous FS data included six HCs, pure and N2-diluted; and three HC-diluted H2 fuels, where FS decayed very nonlinearly as HC was added to H2, due to H-atom scavenging. This study presents FSs on mixtures of (candidate surrogate) HCs, some with very high FS ethylene. Included are four binary gaseous systems at 300 K, and a hot ternary system at approx. 600 K. The binaries are methane + ethylene, ethane + ethylene, methane + ethane, and methane + propylene. The first three also form two ternary systems. The hot ternary includes both 10.8 and 21.3 mole % vaporized n-heptane and full ranges of methane + ethylene. Normalized FS data provide accurate means of (1) validating, globally, chemical kinetics for extinction of non-premixed flames, and (2) estimating (scaling by HC) the loss of incipient flameholding in scramjet combustors. The n-heptane is part of a proposed baseline simulant (10 mole % with 30% methane + 60% ethylene) that mimics the ignition of endothermically cracked JP-7 like kerosene fuel, as suggested by Colket and Spadaccini in 2001 in their shock tube Scramjet Fuels Autoignition Study. Presently, we use FS to gauge idealized flameholding, and define HC surrogates. First, FS was characterized for hot nheptane + methane + ethylene; then a hot 36 mole % methane + 64% ethylene surrogate was defined that mimics FS of the baseline simulant system. A similar hot ethane + ethylene surrogate can also be defined, but it has lower vapor pressure at 300 K, and thus exhibits reduced gaseous

  5. Development of a large support surface for an air-bearing type zero-gravity simulator

    NASA Technical Reports Server (NTRS)

    Glover, K. E.

    1976-01-01

    The methods used in producing a large, flat surface to serve as the supporting surface for an air-bearing type zero-gravity simulator using low clearance, thrust-pad type air bearings are described. Major problems encountered in the use of self-leveled epoxy coatings in this surface are discussed and techniques are recommended which proved effective in overcoming these problems. Performance requirements of the zero-gravity simulator vehicle which were pertinent to the specification of the air-bearing support surface are also discussed.

  6. Quasi-perpetual discharge behaviour in p-type Ge-air batteries.

    PubMed

    Ocon, Joey D; Kim, Jin Won; Abrenica, Graniel Harne A; Lee, Jae Kwang; Lee, Jaeyoung

    2014-11-01

    Metal-air batteries continue to become attractive energy storage and conversion systems due to their high energy and power densities, safer chemistries, and economic viability. Semiconductor-air batteries - a term we first define here as metal-air batteries that use semiconductor anodes such as silicon (Si) and germanium (Ge) - have been introduced in recent years as new high-energy battery chemistries. In this paper, we describe the excellent doping-dependent discharge kinetics of p-type Ge anodes in a semiconductor-air cell employing a gelled KOH electrolyte. Owing to its Fermi level, n-type Ge is expected to have lower redox potential and better electronic conductivity, which could potentially lead to a higher operating voltage and better discharge kinetics. Nonetheless, discharge measurements demonstrated that this prediction is only valid at the low current regime and breaks down at the high current density region. The p-type Ge behaves extremely better at elevated currents, evident from the higher voltage, more power available, and larger practical energy density from a very long discharge time, possibly arising from the high overpotential for surface passivation. A primary semiconductor-air battery, powered by a flat p-type Ge as a multi-electron anode, exhibited an unprecedented full discharge capacity of 1302.5 mA h gGe(-1) (88% anode utilization efficiency), the highest among semiconductor-air cells, notably better than new metal-air cells with three-dimensional and nanostructured anodes, and at least two folds higher than commercial Zn-air and Al-air cells. We therefore suggest that this study be extended to doped-Si anodes, in order to pave the way for a deeper understanding on the discharge phenomena in alkaline metal-air conversion cells with semiconductor anodes for specific niche applications in the future. PMID:24975009

  7. Simulation du fonctionnement de capteurs solaires à air de type tôle et de type absorbeur poreux

    NASA Astrophysics Data System (ADS)

    Fournier, Michel; Maurissen, Yves

    1993-12-01

    The comparison between air-heated insolators, no porous and porous plate, often has been made experimentaly. The behaviour model of these insolators permit generalization of the study in the conditions where each insolator is the most performant. La comparaison des capteurs solaires à air à absorbeur de type tôle et de type poreux a été abordée le plus souvent de façon expérimentale. La modélisation du fonctionnement de ces types de capteur permet de généraliser cette comparaison et de définir les domaines de fonctionnement où un type de capteur se montre plus efficace que l'autre.

  8. Schlieren imaging of loud sounds and weak shock waves in air near the limit of visibility

    NASA Astrophysics Data System (ADS)

    Hargather, Michael John; Settles, Gary S.; Madalis, Matthew J.

    2010-02-01

    A large schlieren system with exceptional sensitivity and a high-speed digital camera are used to visualize loud sounds and a variety of common phenomena that produce weak shock waves in the atmosphere. Frame rates varied from 10,000 to 30,000 frames/s with microsecond frame exposures. Sound waves become visible to this instrumentation at frequencies above 10 kHz and sound pressure levels in the 110 dB (6.3 Pa) range and above. The density gradient produced by a weak shock wave is examined and found to depend upon the profile and thickness of the shock as well as the density difference across it. Schlieren visualizations of weak shock waves from common phenomena include loud trumpet notes, various impact phenomena that compress a bubble of air, bursting a toy balloon, popping a champagne cork, snapping a wooden stick, and snapping a wet towel. The balloon burst, snapping a ruler on a table, and snapping the towel and a leather belt all produced readily visible shock-wave phenomena. In contrast, clapping the hands, snapping the stick, and the champagne cork all produced wave trains that were near the weak limit of visibility. Overall, with sensitive optics and a modern high-speed camera, many nonlinear acoustic phenomena in the air can be observed and studied.

  9. Al-Air Batteries: Fundamental Thermodynamic Limitations from First Principles Theory

    NASA Astrophysics Data System (ADS)

    Chen, Leanne D.; Noerskov, Jens K.; Luntz, Alan C.

    2015-03-01

    The Al-air battery possesses high theoretical specific energy (4140 Wh/kg) and is therefore an attractive candidate for vehicle propulsion applications. However, the experimentally observed open-circuit potential is much lower than what thermodynamics predicts, and this potential loss is widely believed to be an effect of corrosion. We present a detailed study of the Al-air battery using density functional theory. The results suggest that the difference between bulk thermodynamic and surface potentials is due to both the effects of asymmetry in multi-electron transfer reactions that define the anodic dissolution of Al and, more importantly, a large chemical step inherent to the formation of bulk Al(OH)3 from surface intermediates. The former results in an energy loss of 3%, while the latter accounts for 14 -29% of the total thermodynamic energy depending on the surface site where dissolution occurs. Therefore, the maximum open-circuit potential of the Al anode is only -1.87 V vs. SHE in the absence of thermal excitations, contrary to -2.34 V predicted by bulk thermodynamics at pH 14.6. This is a fundamental limitation of the system and governs the maximum output potential, which cannot be improved even if corrosion effects were completely suppressed. Supported by the Natural Sciences and Engineering Research Council of Canada and the ReLiable Project (#11-116792) funded by the Danish Council for Strategic Research.

  10. Equatorial range limits of an intertidal ectotherm are more linked to water than air temperature.

    PubMed

    Seabra, Rui; Wethey, David S; Santos, António M; Gomes, Filipa; Lima, Fernando P

    2016-10-01

    As climate change is expected to impose increasing thermal stress on intertidal organisms, understanding the mechanisms by which body temperatures translate into major biogeographic patterns is of paramount importance. We exposed individuals of the limpet Patella vulgata Linnaeus, 1758, to realistic experimental treatments aimed at disentangling the contribution of water and air temperature for the buildup of thermal stress. Treatments were designed based on temperature data collected at the microhabitat level, from 15 shores along the Atlantic European coast spanning nearly 20° of latitude. Cardiac activity data indicated that thermal stress levels in P. vulgata are directly linked to elevated water temperature, while high air temperature is only stressful if water temperature is also high. In addition, the analysis of the link between population densities and thermal regimes at the studied locations suggests that the occurrence of elevated water temperature may represent a threshold P. vulgata is unable to tolerate. By combining projected temperatures with the temperature threshold identified, we show that climate change will likely result in the westward expansion of the historical distribution gap in the Bay of Biscay (southwest France), and northward contraction of the southern range limit in south Portugal. These findings suggest that even a minor relaxing of the upwelling off northwest Iberia could lead to a dramatic increase in thermal stress, with major consequences for the structure and functioning of the intertidal communities along Iberian rocky shores. PMID:27109165

  11. Al-Air Batteries: Fundamental Thermodynamic Limitations from First-Principles Theory.

    PubMed

    Chen, Leanne D; Nørskov, Jens K; Luntz, Alan C

    2015-01-01

    The Al-air battery possesses high theoretical specific energy (4140 W h/kg) and is therefore an attractive candidate for vehicle propulsion. However, the experimentally observed open-circuit potential is much lower than what bulk thermodynamics predicts, and this potential loss is typically attributed to corrosion. Similarly, large Tafel slopes associated with the battery are assumed to be due to film formation. We present a detailed thermodynamic study of the Al-air battery using density functional theory. The results suggest that the maximum open-circuit potential of the Al anode is only -1.87 V versus the standard hydrogen electrode at pH 14.6 instead of the traditionally assumed -2.34 V and that large Tafel slopes are inherent in the electrochemistry. These deviations from the bulk thermodynamics are intrinsic to the electrochemical surface processes that define Al anodic dissolution. This has contributions from both asymmetry in multielectron transfers and, more importantly, a large chemical stabilization inherent to the formation of bulk Al(OH)3 from surface intermediates. These are fundamental limitations that cannot be improved even if corrosion and film effects are completely suppressed. PMID:26263108

  12. Computational Study of Near-limit Propagation of Detonation in Hydrogen-air Mixtures

    NASA Technical Reports Server (NTRS)

    Yungster, S.; Radhakrishnan, K.

    2002-01-01

    A computational investigation of the near-limit propagation of detonation in lean and rich hydrogen-air mixtures is presented. The calculations were carried out over an equivalence ratio range of 0.4 to 5.0, pressures ranging from 0.2 bar to 1.0 bar and ambient initial temperature. The computations involved solution of the one-dimensional Euler equations with detailed finite-rate chemistry. The numerical method is based on a second-order spatially accurate total-variation-diminishing (TVD) scheme, and a point implicit, first-order-accurate, time marching algorithm. The hydrogen-air combustion was modeled with a 9-species, 19-step reaction mechanism. A multi-level, dynamically adaptive grid was utilized in order to resolve the structure of the detonation. The results of the computations indicate that when hydrogen concentrations are reduced below certain levels, the detonation wave switches from a high-frequency, low amplitude oscillation mode to a low frequency mode exhibiting large fluctuations in the detonation wave speed; that is, a 'galloping' propagation mode is established.

  13. Limitations of symmetry in FE modeling: A comparison of fem and air-coupled resonance imaging

    NASA Astrophysics Data System (ADS)

    Livings, R. A.; Dayal, V.; Barnard, D. J.; Hsu, D. K.

    2012-05-01

    It has long been an accepted practice to use symmetry in Finite Element Modeling. Whenever modeling a large structure, we turn to symmetry in order to significantly reduce the model size and computation time. But is symmetry always the solution to long computation times, and is it always accurate? This study is aimed at modeling a whole ceramic tile and several possible symmetric models under several different loading cases and comparing them to each other and Air-Coupled Ultrasonic scans to determine if the Finite Element Models can accurately predict the vibrational resonance patterns. The reason for the accuracy or inaccuracy will also be examined. The understanding of the limitations of using symmetry to model large structures will be very useful in all future modeling.

  14. 7 CFR 30.38 - Class 3; air-cured types and groups.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., and length of Class 3, Type 31, air-cured tobacco, but which is a low-nicotine strain or variety... which in its cured state is found by an authorized representative of the Department to have a nicotine... be a suitable low-nicotine strain or variety for the production of Type 31-V, by an agency...

  15. SU-8 doped and encapsulated n-type graphene nanomesh with high air stability

    SciTech Connect

    Al-Mumen, Haider; Dong, Lixin; Li, Wen

    2013-12-02

    N-type doping of graphene with long-term chemical stability in air represents a significant challenge for practical application of graphene electronics. This paper reports a reversible doping method to achieve highly stable n-type graphene nanomeshes, in which the SU-8 photoresist simultaneously serves as an effective electron dopant and an excellent encapsulating layer. The chemically stable n-type characteristics of the SU-8 doped graphene were evaluated in air using their Raman spectra, electrical transport properties, and electronic band structures. The SU-8 doping does minimum damage to the hexagonal carbon lattice of graphene and is completely reversible by removing the uncrosslinked SU-8 resist.

  16. AIRE gene analysis in children with autoimmune hepatitis type I or II.

    PubMed

    Lankisch, Tim O; Mourier, Olivia; Sokal, Etienne M; Habes, Dalila; Lacaille, Florence; Bridoux-Henno, Laure; Hermeziu, Bogdan; Lenaerts, Catherine; Strassburg, Christian P; Jacquemin, Emmanuel

    2009-04-01

    The present report describes AIRE gene analysis in 25 children with autoimmune hepatitis type I or II. The heterozygous transversion c.961C > G (p.Ser278Arg) located in exon 7 was identified in 4 patients with autoimmune hepatitis type I, and mostly in those presenting with a positive family history for autoimmune diseases. In this subgroup of patients, the allelic frequency of this polymorphic variant was at least 3-fold higher than in healthy controls. These results suggest that heterozygous AIRE gene mutation may represent a genetic predisposition to childhood autoimmune hepatitis type I. PMID:19322061

  17. Transport characteristics of meander and bispiral types resistive fault current limiters

    NASA Astrophysics Data System (ADS)

    Kim, S. B.; Nishimoto, M.; Joo, J. H.; Murase, S.

    2008-09-01

    The resistive type fault current limiter based on YBCO thin film with high critical current density was proposed and developed because of its fast recovery characteristics. We have been developing a magnetic field measurement system with hall sensor to study the critical current density distribution or magnetic properties of high- Tc superconductors such as thin film, tape conductor and coated conductors. In this study, the transport current distribution in straight line and U-corner region of meander type resistive fault current limiter using YBCO thin film was investigated experimentally. The both axial and radial self-magnetic field components according to the direct (DC) and alternating (AC) transport currents were measured by two-axis hall probe to estimate the current distribution. And also, the self-magnetic field at the corner of bispiral type fault current limiter was measured by two-axis hall probe with a high spatial resolution to compare with the meander type fault current limiter.

  18. Evaluation of Annual Performance of Multi-type Air-conditioners for Buildings

    NASA Astrophysics Data System (ADS)

    Watanabe, Choyu; Ohashi, Ei-Ichiro; Hirota, Masafumi; Nagamatsu, Katsuaki; Nakayama, Hiroshi

    The partial thermal load performance tests of electric-motor driven multi-type air-conditioners for buildings, the rated cooling and heating capacities of which were 56 kW and 63 kW, respectively, were carried out using the air-enthalpy method testing apparatus. Based on the results of those tests, the applicability of JIS B 8616: 2006, which was developed for the estimation of the annual electricity consumption of packaged air-conditioners with rated cooling capacities less than 28 kW, to the multi-type air-conditioners with larger capacities were examined. It was found that JIS B 8616: 2006 generally overestimates COP under a relatively low thermal load operation. As a result, the annual electricity consumption is underestimated by JIS. The prediction error changes depending of the building uses, and it amounted to -17 % in the case of office and -6 % in the detached shop.

  19. Effect of vehicle type on the performance of second generation air bags for child occupants.

    PubMed

    Arbogast, Kristy B; Durbin, Dennis R; Kallan, Michael J; Winston, Flaura K

    2003-01-01

    Passenger air bags experienced considerable design modification in the late 1990s, principally to mitigate risks to child passengers. This study utilized Data from the Partners for Child Passenger Safety study, a large-scale child-focused crash surveillance system, to examine the effect of vehicle type on the differential performance of first and second generation air bags on injuries to restrained children in frontal impact crashes. Our results show that the benefit of second-generation air bags was seen in passenger cars - those children exposed to second-generation air bags were half as likely to sustain a serious injury - and minivans. However, in SUVs the data suggest no reduction in injury risk with the new designs. This field data provides crucial real-world experience to the automotive industry as they work towards the next generation of air bag designs. PMID:12941218

  20. 42 CFR 84.149 - Type C supplied-air respirator, demand and pressure demand class; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.149 Type C supplied-air respirator... air-supply system, and the range of hose length for the respirator. For example, he might specify that... pressure at the point of attachment of the hose to the air-supply system shall not exceed 863 kN/m.2...

  1. 42 CFR 84.149 - Type C supplied-air respirator, demand and pressure demand class; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.149 Type C supplied-air respirator... air-supply system, and the range of hose length for the respirator. For example, he might specify that... pressure at the point of attachment of the hose to the air-supply system shall not exceed 863 kN/m.2...

  2. 42 CFR 84.149 - Type C supplied-air respirator, demand and pressure demand class; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.149 Type C supplied-air respirator... air-supply system, and the range of hose length for the respirator. For example, he might specify that... pressure at the point of attachment of the hose to the air-supply system shall not exceed 863 kN/m.2...

  3. 42 CFR 84.149 - Type C supplied-air respirator, demand and pressure demand class; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.149 Type C supplied-air respirator... air-supply system, and the range of hose length for the respirator. For example, he might specify that... pressure at the point of attachment of the hose to the air-supply system shall not exceed 863 kN/m.2...

  4. Effects of water-contaminated air on blowoff limits of opposed jet hydrogen-air diffusion flames

    NASA Technical Reports Server (NTRS)

    Pellett, Gerald L.; Jentzen, Marilyn E.; Wilson, Lloyd G.; Northam, G. Burton

    1988-01-01

    The effects of water-contaminated air on the extinction and flame restoration of the central portion of N2-diluted H2 versus air counterflow diffusion flames are investigated using a coaxial tubular opposed jet burner. The results show that the replacement of N2 contaminant in air by water on a mole for mole basis decreases the maximum sustainable H2 mass flow, just prior to extinction, of the flame. This result contrasts strongly with the analogous substitution of water for N2 in a relatively hot premixed H2-O2-N2 flame, which was shown by Koroll and Mulpuru (1986) to lead to a significant, kinetically controlled increase in laminar burning velocity.

  5. [Development of new type plastics air turbine handpiece for dental use].

    PubMed

    Kusano, M

    1989-06-01

    The noise generated by the metal air turbine handpiece employed in dental practice is considerable and attended with predominant high frequency components. Therefore, investigation of the noise generation mechanism and development of a silent air turbine handpiece was only a matter of course. In addition, the metal air turbine hardpiece is comparatively heavy and its production cost is high. From this point of view as well, production of a light air turbine handpiece at low cost is also desirable. In order to overcome the objections to the metal air turbine handpiece, appropriate plastics materials were employed wherever possible. In this study, the number of revolutions, noise level, frequency analysis, start pressure and weight of newly produced plastics handpieces and metal handpieces were examined and compared. The following results were obtained: 1. The number of revolutions of single-nozzle type air turbine handpieces encased in plastics housings and fitted with metal turbine rotors was higher than that of all-metal air turbine handpieces. The noise level of the former tended to be lower. 2. The number of revolutions of multi-nozzle type air turbine handpieces encased in plastics housings and fitted with turbine rotors with plastics turbine blades was almost equal to that of similar metal handpieces, with the noise level tending to be lower. 3. In the case of handpieces fitted with turbine rotors with dynamic balance, the number of revolutions was high and the noise level was low. This indicated that dynamic balance was a factor affecting the number of revolutions and noise level. 4. Narrow band sound frequency analysis of single-nozzle type air turbine handpieces showed a sharp peak at the fundamental frequency which was the same as the number of revolutions multiplied by the number of rotor turbine blades. It is thought that the noise from air turbine handpieces was aerodynamic in origin, being generated by the periodical interruption of steady air flow by

  6. 77 FR 15980 - Airworthiness Directives; Alpha Aviation Concept Limited (Type Certificate Previously Held by...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-19

    ... 12866, (2) Is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034... TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 RIN 2120-AA64 Airworthiness Directives; Alpha Aviation Concept Limited (Type Certificate Previously Held by Alpha Aviation Design Limited)...

  7. Precocious presentation of autoimmune polyglandular syndrome type 2 associated with an AIRE mutation.

    PubMed

    Resende, Eduarda; Gόmez, Gemma Novoa; Nascimento, Marta; Loidi, Lourdes; Saborido Fiaño, Rebeca; Cabanas Rodrίguez, Paloma; Castro-Feijoo, Lidia; Barreiro Conde, Jesús

    2015-01-01

    Autoimmune polyglandular syndrome type 2 (type 2 APS), or Schmidt's syndrome, is defined by the presence of Addison's disease in combination with type 1 diabetes and/or autoimmune thyroid disease. The estimated prevalence of this syndrome is 1.4-4.5 per 100,000 inhabitants and it is more frequent in middle-aged females, whilst it is quite rare in children. Type 2 APS, which shows a pattern of autosomal dominant inheritance with low penetrance, has been associated with HLA specific DR3/DQ2 and DR4/DQ8 haplotypes. However, it has been hypothesized that genetic variability in the AIRE gene, which causing type 1 APS, may play a role in more common organ-specific autoimmune conditions like type 1 diabetes, Hashimoto's disease and type 2 APS, among others. Here we present the case of an 8-year-old girl, with a past medical history of type 1 diabetes diagnosed at the age of 3. She was taken to the Emergency Department because she complained of abdominal pain, nausea and vomiting, and her blood analysis revealed a severe hyponatremia. She also had seizures as a consequence of the hyponatremia and frequent hypoglycemia. She was ultimately found to be suffering from autoimmune primary adrenal insufficiency. The combination of both mentioned conditions, type 1 diabetes and Addison's disease, in the absence of chronic mucocutaneous candidiasis, made a diagnosis of type 2 APS plausible in this girl. The genetic study showed two heterozygous variants: NM_000383.2:C.1411C>T (p. Arg471Cys) in exon 12 and IVS9+6G>A in intron 9 of the AIRE gene. The description of an uncommon case of type 2 APS with precocious presentation associated with an AIRE mutation in a very young girl could help to clarify the role of AIRE in the development of autoimmune diseases. PMID:25402387

  8. Limiter

    DOEpatents

    Cohen, S.A.; Hosea, J.C.; Timberlake, J.R.

    1984-10-19

    A limiter with a specially contoured front face is provided. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution. This limiter shape accommodates the various power scrape-off distances lambda p, which depend on the parallel velocity, V/sub parallel/, of the impacting particles.

  9. Sooting Limits Of Diffusion Flames With Oxygen-Enriched Air And Diluted Fuel

    NASA Technical Reports Server (NTRS)

    Sunderland, P. B.; Urban, D. L.; Stocker, D. P.; Chao, B. H.; Axelbaum, R. L.

    2003-01-01

    Oxygen-enhanced combustion permits certain benefits and flexibility that are not otherwise available in the design of practical combustors, as discussed by Baukal. The cost of pure and enriched oxygen has declined to the point that oxygen-enhanced combustion is preferable to combustion in air for many applications. Carbon sequestration is greatly facilitated by oxygen enrichment because nitrogen can be eliminated from the product stream. For example, when natural gas (or natural gas diluted with CO2) is burned in pure oxygen, the only significant products are water and CO2. Oxygen-enhanced combustion also has important implications for soot formation, as explored in this work. We propose that soot inception in nonpremixed flames requires a region where C/O ratio, temperature, and residence time are above certain critical values. Soot does not form at low temperatures, with the threshold in nonpremixed flames ranging from about 1250-1650 K, a temperature referred to here as the critical temperature for soot inception, Tc. Soot inception also can be suppressed when residence time is short (equivalently, when the strain rate in counterflow flames is high). Soot induction times of 0.8-15 ms were reported by Tesner and Shurupov for acetylene/nitrogen mixtures at 1473 K. Burner stabilized spherical microgravity flames are employed in this work for two main reasons. First, this configuration offers unrestricted control over convection direction. Second, in steady state these flames are strain-free and thus can yield intrinsic sooting limits in diffusion flames, similar to the way past work in premixed flames has provided intrinsic values of C/O ratio associated with soot inception limits.

  10. Experimental study of lean flammability limits of methane/hydrogen/air mixtures in tubes of different diameters

    SciTech Connect

    Shoshin, Y.L.; Goey, L.P.H. de

    2010-04-15

    Lean limit flames in methane/hydrogen/air mixtures propagating in tubes of internal diameters (ID) of 6.0, 8.9, 12.3, 18.4, 25.2, 35.0, and 50.2 mm have been experimentally studied. The flames propagated upward from the open bottom end of the tube to the closed upper end. The content of hydrogen in the fuel gas has been varied in the range 0-40 mol%. Lean flammability limits have been determined; flame shapes recorded and the visible speed of flame propagation measured. Most of the observed limit flames in tubes with diameters in the range of 8.9-18.4 mm had enclosed shape, and could be characterized as distorted or spherical flame balls. The tendency was observed for mixtures with higher hydrogen content to form smaller size, more uniform flame balls in a wider range of tube diameters. At hydrogen content of 20% or more in the fuel gas, limit flames in largest diameters (35.0 mm and 50.2 mm ID) tubes had small, compared to the tube diameter, size and were ''lens''-shaped. ''Regular'' open-front lean limit flames were observed only for the smallest diameters (6.0 mm and 8.9 mm) and largest diameters (35.0 and 50.2 mm ID), and only for methane/air and (90% CH{sub 4} + 10% H{sub 2})/air mixtures, except for 6 mm ID tube in which all limit flames had open front. In all experiments, except for the lean limit flames in methane/air and (90% CH{sub 4} + 10% H{sub 2})/air mixtures in the 8.9 mm ID tube, and all limit flames in 6.0 mm ID tube, visible flame speeds very weakly depended on the hydrogen content in the fuel gas and were close to- or below the theoretical estimate of the speed of a rising hot bubble. This observation suggests that the buoyancy is the major factor which determines the visible flame speed for studied limit flames, except that last mentioned. A decrease of the lean flammability limit value with decreasing the tube diameter was observed for methane/air and (90% CH{sub 4} + 10% H{sub 2})/air mixtures for tubes having internal diameters in the range

  11. Limiter

    DOEpatents

    Cohen, Samuel A.; Hosea, Joel C.; Timberlake, John R.

    1986-01-01

    A limiter with a specially contoured front face accommodates the various power scrape-off distances .lambda..sub.p, which depend on the parallel velocity, V.sub..parallel., of the impacting particles. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution.

  12. Thoron ( 220Rn) progeny reduction by an air cleaner of the polarized media filter type

    NASA Astrophysics Data System (ADS)

    Bigu, J.

    1993-02-01

    The effect of an air cleaner on 220Rn progeny atmospheres has been studied in a Radon/Thoron Test Facility (RTTF) of the walk-in type. The air cleaner consists basically of a fan and a special filter material sandwiched between two metal screens, to which an electric field is applied. The filter is of the polarized media type and uses fibreglass as material. The fan and filter system are housed in a metal case. Air is drawn from the back of the case by means of the fan and forced through the "electrical" filter where removal of the 220Rn progeny occurs. Radon-220 progeny "depleted" air is discharged at the top of the device. Tests were conducted in 220Rn/ 220Rn progeny atmospheres when the air cleaner was operating, and when it was turned off. Very pronounced effects were observed during the operation of the device, namely: a dramatic decrease in the 220Rn progeny concentrations and the total aerosol concentration, as well as a large increase in the 220Rn progeny unattached fractions and the plate-out of these radionuclides on the walls of the RTTF. The air cleaner has potential in industrial applications, which should be explored.

  13. FORMALDEHYDE AND TRACER GAS TRANSFER BETWEEN AIRSTREAMS IN ENTHALPY-TYPE AIR-TO-AIR HEAT EXCHANGERS

    SciTech Connect

    Fisk, W. J.; Pedersen, B. S.; Hekmat, D.; Chant, R. E.; Kaboli, H.

    1984-07-01

    Enthalpy exchangers are frequently employed to transfer heat and water between the supply and exhaust airstreams of mechanical ventilation systems. Concern has been expressed that some indoor-generated air pollutants, especially formaldehyde, may be transferred between airstreams by this type of heat exchanger and, thus, returned to the indoor space. This paper describes an experimental study in which the formaldehyde, tracer gas, and water vapor transfer rates in two enthalpy exchangers were measured. The first exchanger uses a crossflow core fabricated from a treated paper. The core of the second heat exchanger is a rotating heat wheel coated with lithium chloride. To reduce the transfer of gases by air leakage each core was installed in a specially fabricated case. Only 5% to 8% of the two tracer gases and 7% to 15% of the formaldehyde injected into the exhaust airstream was transferred to the supply airstream. Therefore, formaldehyde transfer between airstreams by processes other than air leakage does not seriously compromise the performance of these enthalpy exchangers. Theoretical calculations indicate, however, that the transfer of water vapor between airstreams in enthalpy exchangers can significantly diminish their ability to lower indoor formaldehyde concentrations because of the positive coupling between indoor humidity and the emission rates of formaldehyde from building materials.

  14. Functional limitations of plasmacytoid dendritic cells limit type I interferon, T cell responses and virus control in early life.

    PubMed

    Belnoue, Elodie; Fontannaz, Paola; Rochat, Anne-Françoise; Tougne, Chantal; Bergthaler, Andreas; Lambert, Paul-Henri; Pinschewer, Daniel D; Siegrist, Claire-Anne

    2013-01-01

    Infant mortality from viral infection remains a major global health concern: viruses causing acute infections in immunologically mature hosts often follow a more severe course in early life, with prolonged or persistent viral replication. Similarly, the WE strain of lymphocytic choriomeningitis virus (LCMV-WE) causes acute self-limiting infection in adult mice but follows a protracted course in infant animals, in which LCMV-specific CD8⁺ T cells fail to expand and control infection. By disrupting type I IFNs signaling in adult mice or providing IFN-α supplementation to infant mice, we show here that the impaired early life T cell responses and viral control result from limited early type I IFN responses. We postulated that plasmacytoid dendritic cells (pDC), which have been identified as one major source of immediate-early IFN-I, may not exert adult-like function in vivo in the early life microenvironment. We tested this hypothesis by studying pDC functions in vivo during LCMV infection and identified a coordinated downregulation of infant pDC maturation, activation and function: despite an adult-like in vitro activation capacity of infant pDCs, the expression of the E2-2 pDC master regulator (and of critical downstream antiviral genes such as MyD88, TLR7/TLR9, NF-κB, IRF7 and IRF8) is downregulated in vivo at baseline and during LCMV infection. A similar pattern was observed in response to ssRNA polyU, a model ligand of the TLR7 viral sensor. This suggests that the limited T cell-mediated defense against early life viral infections is largely attributable to / regulated by infant pDC responses and provides incentives for novel strategies to supplement or stimulate immediate-early IFN-α responses. PMID:24376875

  15. The Role of Oxygen in Determining Upper Thermal Limits in Lottia digitalis under Air Exposure and Submersion.

    PubMed

    Bjelde, Brittany E; Miller, Nathan A; Stillman, Jonathon H; Todgham, Anne E

    2015-01-01

    Oxygen limitation of aerobic metabolism is hypothesized to drive organismal thermal tolerance limits. Differences in oxygen availability in air and water may underlie observed differences in upper thermal tolerance of intertidal limpets if oxygen is limiting in submerged environments. We explored how cardiac performance (heart rate, breakpoint temperature [BPT], flat-line temperature [FLT], and temperature sensitivity) was affected by hyperoxia and hypoxia in the finger limpet, Lottia digitalis, under air exposure and submersion. Upper thermal tolerance limits were unchanged by increasing availability of oxygen, although air-exposed limpets were able to maintain cardiac function to higher temperatures than submerged limpets. Maximum heart rate did not increase with greater partial pressure of oxygen (Po2), suggesting that tissue Po2 levels are likely maximized during normoxia. Hypoxia reduced breakpoint BPTs and FLTs in air-exposed and submerged limpets and accentuated the difference in BPTs between the two groups through greater reductions in BPT in submerged limpets. Differences in respiratory structures and the degree to which thermal limits are already maximized may play significant roles in determining how oxygen availability influences upper temperature tolerance. PMID:26658246

  16. An Adsorption Type Humidifier for Automobiles and Interior Air Quality Improvement

    NASA Astrophysics Data System (ADS)

    Moriya, Yoshifumi; Ishii, Noriaki

    This study presents a new adsorption material type humidifier for automobiles, in which the moisture in the outside air is adsorbed onto a solid desiccant material and the adsorbed water is then used as the humidifying source for the interior air of the car, that is, no additional water supply for humidification is required. The new humidifier was installed in a test car under actual conditions, and the humidification performance and the interior air quality, as determined by CO2, O2, dust concentration and SnO2, output, were measured. A comparison between the data for the new humidifier and those for an ultrasonic humidifier showed that the humidification ability was adequate but the interior air quality was far better when the new humidifier was used. Finally, the results of longevity tests, repeated adsorption/desorption tests and acid-gas poisoning tests are presented.

  17. Measurements of two types of dilatational waves in an air-filled unconsolidated sand

    SciTech Connect

    Hickey, C.J.; Sabatier, J.M.

    1997-07-01

    This study consists of laboratory measurements of dilatational waves propagating through an air-filled unconsolidated sand. One excitation technique consists of a loudspeaker suspended in the air above the packing of sand. A second excitation technique uses a mechanical shaker in contact with the sand. The transmitted signals are received using microphones and geophones located at various depths within the sand. An interpretation based on measured phase speeds indicates that the transmitted energy from the suspended loudspeaker source is partitioned primarily but not exclusively into the type-II dilatational wave. This wave attenuates rapidly and is only detected at depths of less than about 15 cm for this particular sample. At the deeper depths the detected signal is associated with the type-I dilatational wave. The mechanical shaker produces only a type-I dilatational wave. Both the geophone and microphone sensors can detect both types of dilatational waves. {copyright} {ital 1997 Acoustical Society of America.}

  18. Optimum Aeroelastic Design of Resonance Type Flapping Wing for Micro Air Vehicles

    NASA Astrophysics Data System (ADS)

    Isogai, Koji; Kamisawa, Yuichi; Sato, Hiroyuki

    The optimum aeroelastic design method for a resonance-type flapping wing for a Micro Air Vehicle (MAV) is presented. It uses Complex Method and 3D Navier-Stokes code to determine the optimum structural and aerodynamic parameters of a 2 DOF flapping wing system. The method is used to design a dragonfly-type MAV, and numerical simulation shows that the designed flapping wings can generate sufficient lift to sustain the weight and sufficient thrust to overcome the body drag.

  19. 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 class; minimum requirements. 84.148 Section 84.148 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES...

  20. 78 FR 40063 - Airworthiness Directives; Erickson Air-Crane Incorporated Helicopters (Type Certificate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-03

    ...We propose to supersede an existing airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-64E helicopters. The existing AD requires checks of the main rotor blades for a crack. This proposed AD would retain the actions of the existing AD, would reflect that the type certificate (TC) for this model helicopter has been transferred to Erickson Air-Crane Incorporated......

  1. High-performance air-stable n-type carbon nanotube transistors with erbium contacts.

    PubMed

    Shahrjerdi, Davood; Franklin, Aaron D; Oida, Satoshi; Ott, John A; Tulevski, George S; Haensch, Wilfried

    2013-09-24

    So far, realization of reproducible n-type carbon nanotube (CNT) transistors suitable for integrated digital applications has been a difficult task. In this work, hundreds of n-type CNT transistors from three different low work function metals-erbium, lanthanum, and yttrium-are studied and benchmarked against p-type devices with palladium contacts. The crucial role of metal type and deposition conditions is elucidated with respect to overall yield and performance of the n-type devices. It is found that high oxidation rates and sensitivity to deposition conditions are the major causes for the lower yield and large variation in performance of n-type CNT devices with low work function metal contacts. Considerable improvement in device yield is attained using erbium contacts evaporated at high deposition rates. Furthermore, the air-stability of our n-type transistors is studied in light of the extreme sensitivity of these metals to oxidation. PMID:24006886

  2. Nitric Oxide and Oxygen Air-Contamination Effects on Extinction Limits of Non-Premixed Hydrocarbon-Air Flames for a HIFiRE Scramjet

    NASA Technical Reports Server (NTRS)

    Pellett, Gerald L.; Dawson, Lucy C.; Vaden, Sarah N.; Wilson, Lloyd G.

    2009-01-01

    Unique nitric oxide (NO) and oxygen air-contamination effects on the extinction Flame Strength (FS) of non-premixed hydrocarbon (HC) vs. air flames are characterized for 7 gaseous HCs, using a new idealized 9.3 mm straight-tube Opposed Jet Burner (OJB) at 1 atm. FS represents a laminar strain-induced extinction limit based on cross-section-average air jet velocity, Uair, that sustains combustion of a counter jet of gaseous fuel just before extinction. Besides ethane, propane, butane, and propylene, the HCs include ethylene, methane, and a 64 mole-% ethylene / 36 % methane mixture, the writer s previously recommended gaseous surrogate fuel for HIFiRE scramjet tests. The HC vs. clean air part of the work is an extension of a May 2008 JANNAF paper that characterized surrogates for the HIFiRE project that should mimic the flameholding of reformed (thermally- or catalytically-cracked) endothermic JP-like fuels. The new FS data for 7 HCs vs. clean air are thus consolidated with the previously validated data, normalized to absolute (local) axial-input strain rates, and co-plotted on a dual kinetically dominated reactivity scale. Excellent agreement with the prior data is obtained for all 7 fuels. Detailed comparisons are also made with recently published (Univ. Va) numerical results for ethylene extinction. A 2009-revised ethylene kinetic model (Univ. Southern Cal) led to predicted limits within approx. 5 % (compared to 45 %, earlier) of this writer s 2008 (and present) ethylene FSs, and also with recent independent data (Univ. Va) obtained on a new OJB system. These +/- 5 % agreements, and a hoped-for "near-identically-performing" reduced kinetics model, would greatly enhance the capability for accurate numerical simulations of surrogate HC flameholding in scramjets. The measured air-contamination effects on normalized FS extinction limits are projected to assess ongoing Arc-Heater-induced "facility test effects" of NO production (e.g., 3 mole-%) and resultant oxygen

  3. The development of an aluminum toroidal shell-type impact limiter

    SciTech Connect

    Mello, R.M.; Wilson, W.K.; Nair, B.R.

    1989-01-01

    The impact limiters on a Type B transportation cask are designed to absorb the impact energy for the 9-meter (30 foot) drop accident conditions without bottoming out in order to limit deceleration loadings on the cask. Toroidal shell-type impact limiters made from stainless steel have been investigated in the past for transportation cask service in Japan (Y. Sugita and S. Mochizuki) and by the General Electric Company (R.J. Pomares, et al.). These designs were relatively heavy and quite rigid causing high deceleration loads on the cask. This paper presents the results of an investigation to determine the feasibility of an aluminum Alloy 6061-T6 toroidal shell impact limiter for a Legal Weight Truck (LWT) cask being developed by the Westinghouse Corporation for the United States Department of Energy. The incentives for the study were the potential advantages such as a compact configuration, lightweight, durability, and essentially maintenance-free operation. 4 refs., 10 figs.

  4. SIMAIR—Evaluation tool for meeting the EU directive on air pollution limits

    NASA Astrophysics Data System (ADS)

    Gidhagen, L.; Johansson, H.; Omstedt, G.

    Almost all Swedish cities need to determine air pollution levels—especially PM10—close to major streets. SIMAIR is an internet tool that can be used by all Swedish municipalities to assess PM10, NO 2, CO and benzene levels and how they compare to the EU directive. SIMAIR is delivered to the municipalities with all required input data pre-loaded and is meant to be used prior to decisions if and where, monitoring campaigns are required. The system includes a road and vehicle database with emission factors and a model to calculate non-tailpipe PM10 emissions. Regional and urban background contributions are pre-calculated and stored as hourly values on a 1×1 km 2 grid. The local contribution is calculated by the user, selecting either an open road or a street canyon environment. A comparison between measured and simulated concentrations in four street locations shows that SIMAIR is able to calculate statistics of yearly mean values, 90-percentile and 98-percentile daily mean values and the number of days exceeding the limit value that are well within ±50% that EU requires for model estimates of yearly mean values. In comparison, all values except one are within ±25% which is the quality objective for fixed measurements according to the EU directive. The SIMAIR model system is also able to separate the percentual contribution of the long-range transport from outside the city, the city contribution and the local contribution from the traffic of an individual street.

  5. 10 CFR Appendix B to Part 20 - Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) of Radionuclides for...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) of Radionuclides for Occupational Exposure; Effluent Concentrations; Concentrations for Release to Sewerage B Appendix B to Part 20 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Pt. 20, App. B Appendix...

  6. 10 CFR Appendix B to Part 20 - Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) of Radionuclides for...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) of Radionuclides for Occupational Exposure; Effluent Concentrations; Concentrations for Release to Sewerage B Appendix B to Part 20 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Pt. 20, App. B Appendix...

  7. CfAIR2: Near-infrared Light Curves of 94 Type Ia Supernovae

    NASA Astrophysics Data System (ADS)

    Friedman, Andrew S.; Wood-Vasey, W. M.; Marion, G. H.; Challis, Peter; Mandel, Kaisey S.; Bloom, Joshua S.; Modjaz, Maryam; Narayan, Gautham; Hicken, Malcolm; Foley, Ryan J.; Klein, Christopher R.; Starr, Dan L.; Morgan, Adam; Rest, Armin; Blake, Cullen H.; Miller, Adam A.; Falco, Emilio E.; Wyatt, William F.; Mink, Jessica; Skrutskie, Michael F.; Kirshner, Robert P.

    2015-09-01

    CfAIR2 is a large, homogeneously reduced set of near-infrared (NIR) light curves (LCs) for Type Ia supernovae (SNe Ia) obtained with the 1.3 m Peters Automated InfraRed Imaging TELescope. This data set includes 4637 measurements of 94 SNe Ia and 4 additional SNe Iax observed from 2005 to 2011 at the Fred Lawrence Whipple Observatory on Mount Hopkins, Arizona. CfAIR2 includes {{JHK}}s photometric measurements for 88 normal and 6 spectroscopically peculiar SN Ia in the nearby universe, with a median redshift of z ˜ 0.021 for the normal SN Ia. CfAIR2 data span the range from -13 days to +127 days from B-band maximum. More than half of the LCs begin before the time of maximum, and the coverage typically contains ˜13-18 epochs of observation, depending on the filter. We present extensive tests that verify the fidelity of the CfAIR2 data pipeline, including comparison to the excellent data of the Carnegie Supernova Project. CfAIR2 contributes to a firm local anchor for SN cosmology studies in the NIR. Because SN Ia are more nearly standard candles in the NIR and are less vulnerable to the vexing problems of extinction by dust, CfAIR2 will help the SN cosmology community develop more precise and accurate extragalactic distance probes to improve our knowledge of cosmological parameters, including dark energy and its potential time variation.

  8. Vitamin E alters alveolar type II cell phospholipid synthesis in oxygen and air

    SciTech Connect

    Kennedy, K.A.; Snyder, J.M.; Stenzel, W.; Saito, K.; Warshaw, J.B. )

    1990-11-01

    Newborn rats were injected with vitamin E or placebo daily until 6 days after birth. The effect of vitamin E pretreatment on in vitro surfactant phospholipid synthesis was examined in isolated type II cells exposed to oxygen or air form 24 h in vitro. Type II cells were also isolated from untreated 6-day-old rats and cultured for 24 h in oxygen or air with control medium or vitamin E supplemented medium. These cells were used to examine the effect of vitamin E exposure in vitro on type II cell phospholipid synthesis and ultrastructure. Phosphatidylcholine (PC) synthesis was reduced in cells cultured in oxygen as compared with air. This decrease was not prevented by in vivo pretreatment or in vitro supplementation with vitamin E. Vitamin E pretreatment increased the ratio of disaturated PC to total PC and increased phosphatidylglycerol synthesis. The volume density of lamellar bodies in type II cells was increased in cells maintained in oxygen. Vitamin E did not affect the volume density of lamellar bodies. We conclude that in vitro hyperoxia inhibits alveolar type II cell phosphatidylcholine synthesis without decreasing lamellar body volume density and that supplemental vitamin E does not prevent hyperoxia-induced decrease in phosphatidylcholine synthesis.

  9. Performance Characteristics of Cross-Fin-Tube-Type Heat Exchanger for Air Conditioner

    NASA Astrophysics Data System (ADS)

    Sasaki, Naoe; Kakiyama, Shiro; Sanuki, Noriyoshi

    The effects of enhanced heat transfer tube with ability to control the heat transfer disturbance by mechanical tube expanding were experimentally investigated on the performance characteristics of air-cooled cross-fin-tube-type heat exchanger for air conditioner. Three kinds of the enhanced heat transfer tube were developed and used in the experiment. The enhanced heat transfer tube was a kind of spirally grooved tube and composed with the fins smaller than those of the conventional spirally grooved tube excepting four fins located in orthogonal position on the tube circumference. The optimum groove number to enhance the performance of heat exchanger was also shown.

  10. A numerical study of the influence of ammonia addition on the auto-ignition limits of methane/air mixtures.

    PubMed

    Van den Schoor, F; Norman, F; Vandebroek, L; Verplaetsen, F; Berghmans, J

    2009-05-30

    In this study the auto-ignition limit of ammonia/methane/air mixtures is calculated based upon a perfectly stirred reactor model with convective heat transfer. The results of four different reaction mechanisms are compared with existing experimental data at an initial temperature of 723 K with ammonia concentrations of 0-20 mol.% and methane concentrations of 2.5-10 mol.%. It is found that the calculation of the auto-ignition limit pressure at constant temperature leads to larger relative deviations between calculated and experimental results than the calculation of the auto-ignition temperature at constant pressure. In addition to the calculations, a reaction path analysis is performed to explain the observed lowering of the auto-ignition limit of methane/air mixtures by ammonia addition. It is found that this decrease is caused by the formation of NO and NO(2), which enhance the oxidation of methane at low temperatures. PMID:18926632

  11. 41 CFR 102-73.65 - Are there any limitations on leasing certain types of space?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Are there any limitations on leasing certain types of space? 102-73.65 Section 102-73.65 Public Contracts and Property... that leasing such space is necessary to meet requirements that cannot be met in public buildings,...

  12. 41 CFR 102-73.65 - Are there any limitations on leasing certain types of space?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Are there any limitations on leasing certain types of space? 102-73.65 Section 102-73.65 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 73-REAL ESTATE ACQUISITION Acquisition...

  13. Air density 2.7 billion years ago limited to less than twice modern levels by fossil raindrop imprints.

    PubMed

    Som, Sanjoy M; Catling, David C; Harnmeijer, Jelte P; Polivka, Peter M; Buick, Roger

    2012-04-19

    According to the 'Faint Young Sun' paradox, during the late Archaean eon a Sun approximately 20% dimmer warmed the early Earth such that it had liquid water and a clement climate. Explanations for this phenomenon have invoked a denser atmosphere that provided warmth by nitrogen pressure broadening or enhanced greenhouse gas concentrations. Such solutions are allowed by geochemical studies and numerical investigations that place approximate concentration limits on Archaean atmospheric gases, including methane, carbon dioxide and oxygen. But no field data constraining ground-level air density and barometric pressure have been reported, leaving the plausibility of these various hypotheses in doubt. Here we show that raindrop imprints in tuffs of the Ventersdorp Supergroup, South Africa, constrain surface air density 2.7 billion years ago to less than twice modern levels. We interpret the raindrop fossils using experiments in which water droplets of known size fall at terminal velocity into fresh and weathered volcanic ash, thus defining a relationship between imprint size and raindrop impact momentum. Fragmentation following raindrop flattening limits raindrop size to a maximum value independent of air density, whereas raindrop terminal velocity varies as the inverse of the square root of air density. If the Archaean raindrops reached the modern maximum measured size, air density must have been less than 2.3 kg m(-3), compared to today's 1.2 kg m(-3), but because such drops rarely occur, air density was more probably below 1.3 kg m(-3). The upper estimate for air density renders the pressure broadening explanation possible, but it is improbable under the likely lower estimates. Our results also disallow the extreme CO(2) levels required for hot Archaean climates. PMID:22456703

  14. Effects of hole localization on limiting p-type conductivity in oxide and nitride semiconductors

    SciTech Connect

    Lyons, J. L.; Janotti, A.; Van de Walle, C. G.

    2014-01-07

    We examine how hole localization limits the effectiveness of substitutional acceptors in oxide and nitride semiconductors and explain why p-type doping of these materials has proven so difficult. Using hybrid density functional calculations, we find that anion-site substitutional impurities in AlN, GaN, InN, and ZnO lead to atomic-like states that localize on the impurity atom itself. Substitution with cation-site impurities, on the other hand, triggers the formation of polarons that become trapped on nearest-neighbor anions, generally leading to large ionization energies for these acceptors. Unlike shallow effective-mass acceptors, these two types of deep acceptors couple strongly with the lattice, significantly affecting the optical properties and severely limiting prospects for achieving p-type conductivity in these wide-band-gap materials.

  15. A comparison of measured radiances from AIRS and HIRS across different cloud types

    NASA Astrophysics Data System (ADS)

    Schreier, M. M.; Kahn, B. H.; Staten, P.

    2015-12-01

    The observation of Earth's atmosphere with passive remote sensing instruments is ongoing for decades and resulting in a long-term global dataset. Two prominent examples are operational satellite platforms from the National Oceanic and Atmospheric Administration (NOAA) or research platforms like NASA's Earth Observing System (EOS). The observed spectral ranges of these observations are often similar among the different platforms, but have large differences when it comes to resolution, accuracy and quality control. Our approach is to combine different kinds of instruments at the pixel-scale to improve the characterization of infrared radiances. We focus on data from the High-resolution Infrared Radiation Sounder (HIRS) and compare the observations to radiances from the Atmospheric Infrared Sounder (AIRS) on Aqua. The high spectral resolution of AIRS is used to characterize and possibly recalibrate the observed radiances from HIRS. Our approach is unique in that we use additional information from other passive instruments on the same platforms including the Advanced Very High Resolution Radiometer (AVHRR) and the MODerate resolution Imaging Spectroradiometer (MODIS). We will present comparisons of radiances from HIRS and AIRS within different types of clouds that are determined from the imagers. In this way, we can analyze and select the most homogeneous conditions for radiance comparisons and a possible re-calibration of HIRS. We hope to achieve a cloud-type-dependent calibration and quality control for HIRS, which can be extrapolated into the past via inter-calibration of the different HIRS instruments beyond the time of AIRS.

  16. Effects of Automation Types on Air Traffic Controller Situation Awareness and Performance

    NASA Technical Reports Server (NTRS)

    Sethumadhavan, A.

    2009-01-01

    The Joint Planning and Development Office has proposed the introduction of automated systems to help air traffic controllers handle the increasing volume of air traffic in the next two decades (JPDO, 2007). Because fully automated systems leave operators out of the decision-making loop (e.g., Billings, 1991), it is important to determine the right level and type of automation that will keep air traffic controllers in the loop. This study examined the differences in the situation awareness (SA) and collision detection performance of individuals when they worked with information acquisition, information analysis, decision and action selection and action implementation automation to control air traffic (Parasuraman, Sheridan, & Wickens, 2000). When the automation was unreliable, the time taken to detect an upcoming collision was significantly longer for all the automation types compared with the information acquisition automation. This poor performance following automation failure was mediated by SA, with lower SA yielding poor performance. Thus, the costs associated with automation failure are greater when automation is applied to higher order stages of information processing. Results have practical implications for automation design and development of SA training programs.

  17. Source evaluation report phase 2 investigation: Limited field investigation. Final report: United States Air Force Environmental Restoration Program, Eielson Air Force Base, Alaska

    SciTech Connect

    Not Available

    1994-10-01

    This report describes the limited field investigation work done to address issues and answer unresolved questions regarding a collection of potential contaminant sources at Eielson Air Force Base (AFB), near Fairbanks, Alaska. These sources were listed in the Eielson AFB Federal Facility Agreement supporting the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) cleanup of the base. The limited field investigation began in 1993 to resolve all remaining technical issues and provide the data and analysis required to evaluate the environmental hazard associated with these sites. The objective of the limited field investigation was to allow the remedial project managers to sort each site into one of three categories: requiring remedial investigation/feasibility study, requiring interim removal action, or requiring no further remedial action.

  18. Tornado-type convection with moist ascending and dry descending air

    NASA Astrophysics Data System (ADS)

    Rutkevich, P. B.; Rutkevych, B. P.

    2010-05-01

    According to observations the tornado vortex in horizontal direction can be by convention divided into three parts: the internal part, the intermediate moist convective part and the surrounding part. In the convective part the moist air ascends and a big amount of latent heat is released which is the main energy source of formation and maintenance of the vortex. In the other parts of the structure takes place dissipation of this released energy. So in the second intermediate region the vertical temperature distribution is near to moist-adiabatic while in the other regions it is near to the dry- adiabatic. This leads to a complex convective process of the Ostroumov problem type infinite in horizontal direction with two vertical intermediate cylindrical boundaries. To find solution of such a problem it is necessary to make matching of the considered fields on these boundaries. This problem was considered with the use of Navier-Stokes equations and with the necessary matching at the boundaries. It was obtained that radial distribution of air flux depends on the stable vertical temperature distribution in the surrounding area. At strong stable stratification the vertical air velocity is maximal at the central part of the vortex and at weak stratification the almost neutrally stratified air is easily entrained upward by the strong vertical motion of the moist air in the second region.

  19. Quantum-projection-noise-limited interferometry with coherent atoms in a Ramsey-type setup

    SciTech Connect

    Doering, D.; McDonald, G.; Debs, J. E.; Figl, C.; Altin, P. A.; Bachor, H.-A.; Robins, N. P.; Close, J. D.

    2010-04-15

    Every measurement of the population in an uncorrelated ensemble of two-level systems is limited by what is known as the quantum projection noise limit. Here, we present quantum-projection-noise-limited performance of a Ramsey-type interferometer using freely propagating coherent atoms. The experimental setup is based on an electro-optic modulator in an inherently stable Sagnac interferometer, optically coupling the two interfering atomic states via a two-photon Raman transition. Going beyond the quantum projection noise limit requires the use of reduced quantum uncertainty (squeezed) states. The experiment described demonstrates atom interferometry at the fundamental noise level and allows the observation of possible squeezing effects in an atom laser, potentially leading to improved sensitivity in atom interferometers.

  20. 42 CFR 84.143 - Terminal fittings or chambers; Type B supplied-air respirators; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Terminal fittings or chambers; Type B supplied-air... HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.143 Terminal fittings or chambers; Type...

  1. 42 CFR 84.157 - Airflow resistance test; Type C supplied-air respirator, pressure-demand class; minimum...

    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 respirator, pressure-demand class; minimum requirements. 84.157 Section 84.157 Public Health PUBLIC HEALTH... test; Type C supplied-air respirator, pressure-demand class; minimum requirements. (a) The...

  2. 42 CFR 84.157 - Airflow resistance test; Type C supplied-air respirator, pressure-demand class; minimum...

    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 respirator, pressure-demand class; minimum requirements. 84.157 Section 84.157 Public Health PUBLIC HEALTH... test; Type C supplied-air respirator, pressure-demand class; minimum requirements. (a) The...

  3. 42 CFR 84.157 - Airflow resistance test; Type C supplied-air respirator, pressure-demand class; minimum...

    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 respirator, pressure-demand class; minimum requirements. 84.157 Section 84.157 Public Health PUBLIC HEALTH... test; Type C supplied-air respirator, pressure-demand class; minimum requirements. (a) The...

  4. 42 CFR 84.157 - Airflow resistance test; Type C supplied-air respirator, pressure-demand class; minimum...

    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 respirator, pressure-demand class; minimum requirements. 84.157 Section 84.157 Public Health PUBLIC HEALTH... test; Type C supplied-air respirator, pressure-demand class; minimum requirements. (a) The...

  5. 77 FR 50660 - Limited Approval and Disapproval of Air Quality Implementation Plans; Nevada; Clark County...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-22

    ... INFORMATION: On July 24, 2012 (77 FR 43206), EPA proposed a limited approval and limited disapproval of the... through www.regulations.gov or email. www.regulations.gov is an anonymous access system, and EPA will...

  6. The effect of incomplete fuel-air mixing on the lean blowout limit, lean stability limit and NO(x) emissions in lean premixed gas turbine combustors

    NASA Technical Reports Server (NTRS)

    Shih, W.-P.; Lee, J. G.; Santavicca, D. A.

    1994-01-01

    Gas turbine engines for both land-based and aircraft propulsion applications are facing regulations on NOx emissions which cannot be met with current combustor technology. A number of alternative combustor strategies are being investigated which have the potential capability of achieving ultra-low NOx emissions, including lean premixed combustors, direct injection combustors, rich burn-quick quench-lean burn combustors and catalytic combustors. The research reported in this paper addresses the effect of incomplete fuel-air mixing on the lean limit performance and the NOx emissions characteristics of lean premixed combustors.

  7. Monte Carlo correction factors for the ARPANSA kilovoltage free-air chambers and the effect of moving the limiting aperture

    NASA Astrophysics Data System (ADS)

    Lye, J. E.; Butler, D. J.; Webb, D. V.

    2010-02-01

    ARPANSA has calculated new Monte Carlo corrections for their low and medium energy x-ray free-air chambers. The new calculations include a diverging beam and details of the limiting aperture. The diverging beam simulations are compared with previous parallel beam simulations. The electron loss, scattering and fluorescence corrections do not change when beam divergence is included, even for the short source-detector distance of 30 cm used in post-2008 low energy calibrations. Transmission and scattering from the aperture are significant for both free-air chambers and dependent on the beam divergence. The constancy of the correction factors with changing air path length was investigated at low energies. In the extreme conditions of 100 kV and a distance of 30 cm the correction factors showed significant deviation.

  8. Development of an algorithm to regulate pump output for a closed air-loop type pneumatic biventricular assist device.

    PubMed

    Nam, Kyoung Won; Lee, Jung Joo; Hwang, Chang Mo; Choi, Jaesoon; Choi, Hyuk; Choi, Seong Wook; Sun, Kyung

    2009-12-01

    The closed air space-type of extracorporeal pneumatic ventricular assist device (VAD) developed by the Korea Artificial Organ Center utilizes a bellows-transforming mechanism to generate the air pressure required to pump blood. This operating mechanism can reduce the size and weight of the driving unit; however, the output of the blood pump can be affected by the pressure loading conditions of the blood sac. Therefore, to guarantee a proper pump output level, regardless of the pressure loading conditions that vary over time, automatic pump output regulation of the blood pump is required. We describe herein a pump output regulation algorithm that was developed to maintain pump output around a reference level against various afterload pressures, and verified the pump performance in vitro. Based on actual operating conditions in animal experiments, the pumping rate was limited to 40-84 beats per minute, and the afterload pressure was limited to 80-150 mm Hg. The tested reference pump output was 4.0 L/min. During experiments, the pump output was successfully and automatically regulated within the preset area regardless of the varying afterload conditions. The results of this preliminary experiment can be used as the basis for an automatic control algorithm that can enhance the stability and reliability of the applied VAD. PMID:19604228

  9. A method to derive the relationship between the annual and short-term air quality limits--analysis using the WHO Air Quality Guidelines for health protection.

    PubMed

    Lai, Hak-Kan; Hedley, Anthony J; Thach, Thuan-Quoc; Wong, Chit-Ming

    2013-09-01

    The World Health Organization (WHO) Air Quality Guidelines (AQG) were launched in 2006, but gaps remain in evidence on health impacts and relationships between short-term and annual AQG needed for health protection. We tested whether relationships between WHO short-term and annual AQG for particulates (PM10 and PM2.5) and nitrogen dioxide (NO2) are concordant worldwide and derived the annual limits for sulfur dioxide (SO2) and ozone (O3) based on the short-term AQG. We obtained air pollutant data over seven years (2004-2010) in seven cities from Asia-Pacific, North America and Europe. Based on probability distribution concept using maximum as the short-term limit and arithmetic mean as the annual limit, we developed a new method to derive limit value one from another in each paired limits for each pollutant with capability to account for allowable exceedances. We averaged the limit derived each year for each city, then used meta-analysis to pool the limit values in all cities. Pooled mean short-term limit for NO2 (140.5μg/m(3) [130.6-150.4]) was significantly lower than the WHO AQG of 200μg/m(3) while for PM10 (46.4μg/m(3) [95CI:42.1-50.7]) and PM2.5 (28.6μg/m(3) [24.5-32.6]) were not significantly different from the WHO AQG of 50 and 25μg/m(3) respectively. Pooled mean annual limits for SO2 and O3 were 4.6μg/m(3) [3.7-5.5] and 27.0μg/m(3) [21.7-32.2] respectively. Results were robust in various sensitivity analyses. The distribution relationships between the current WHO short-term and annual AQG are supported by empirical data from seven cities for PM10 and PM2.5, but not for NO2. The short-term AQG for NO2 should be lowered for concordance with the selected annual AQG for health protection. PMID:23792417

  10. Long-Term Exposure to Air Pollution and Type 2 Diabetes Mellitus in a Multiethnic Cohort

    PubMed Central

    Park, Sung Kyun; Adar, Sara D.; O'Neill, Marie S.; Auchincloss, Amy H.; Szpiro, Adam; Bertoni, Alain G.; Navas-Acien, Ana; Kaufman, Joel D.; Diez-Roux, Ana V.

    2015-01-01

    Although air pollution has been suggested as a possible risk factor for type 2 diabetes mellitus (DM), results from existing epidemiologic studies have been inconsistent. We investigated the associations of prevalence and incidence of DM with long-term exposure to air pollution as estimated using annual average concentrations of particulate matter with an aerodynamic diameter of 2.5 μm or less (PM2.5) and nitrogen oxides at baseline (2000) in the Multi-Ethnic Study of Atherosclerosis. All participants were aged 45–84 years at baseline and were recruited from 6 US sites. There were 5,839 participants included in the study of prevalent DM and 5,135 participants without DM at baseline in whom we studied incident DM. After adjustment for potential confounders, we found significant associations of prevalent DM with PM2.5 (odds ratio (OR) = 1.09, 95% confidence interval (CI): 1.00, 1.17) and nitrogen oxides (OR = 1.18, 95% CI: 1.01, 1.38) per each interquartile-range increase (2.43 µg/m3 and 47.1 ppb, respectively). Larger but nonsignificant associations were observed after further adjustment for study site (for PM2.5, OR = 1.16, 95% CI: 0.94, 1.42; for nitrogen oxides, OR = 1.29, 95% CI: 0.94, 1.76). No air pollution measures were significantly associated with incident DM over the course of the 9-year follow-up period. Results were partly consistent with a link between long-term exposure to air pollution and the risk of type 2 DM. Additional studies with a longer follow-up time and a greater range of air pollution exposures, including high levels, are warranted to evaluate the hypothesized association. PMID:25693777

  11. Increasing the Upper Temperature Oxidation Limit of Alumina Forming Austenitic Stainless Steels in Air with Water Vapor

    SciTech Connect

    Brady, Michael P; Unocic, Kinga A; Lance, Michael J; Santella, Michael L; Yamamoto, Yukinori; Walker, Larry R

    2011-01-01

    A family of alumina-forming austenitic (AFA) stainless steels is under development for use in aggressive oxidizing conditions from {approx}600-900 C. These alloys exhibit promising mechanical properties but oxidation resistance in air with water vapor environments is currently limited to {approx}800 C due to a transition from external protective alumina scale formation to internal oxidation of aluminum with increasing temperature. The oxidation behavior of a series of AFA alloys was systematically studied as a function of Cr, Si, Al, C, and B additions in an effort to provide a basis to increase the upper-temperature oxidation limit. Oxidation exposures were conducted in air with 10% water vapor environments from 800-1000 C, with post oxidation characterization of the 900 C exposed samples by electron probe microanalysis (EPMA), scanning and transmission electron microscopy, and photo-stimulated luminescence spectroscopy (PSLS). Increased levels of Al, C, and B additions were found to increase the upper-temperature oxidation limit in air with water vapor to between 950 and 1000 C. These findings are discussed in terms of alloy microstructure and possible gettering of hydrogen from water vapor at second phase carbide and boride precipitates.

  12. Disrupted Nitric Oxide Metabolism from Type II Diabetes and Acute Exposure to Particulate Air Pollution

    PubMed Central

    Pettit, Ashley P.; Kipen, Howard; Laumbach, Robert; Ohman-Strickland, Pamela; Kelly-McNeill, Kathleen; Cepeda, Clarimel; Fan, Zhi-Hua; Amorosa, Louis; Lubitz, Sara; Schneider, Stephen; Gow, Andrew

    2015-01-01

    Type II diabetes is an established cause of vascular impairment. Particulate air pollution is known to exacerbate cardiovascular and respiratory conditions, particularly in susceptible populations. This study set out to determine the impact of exposure to traffic pollution, with and without particle filtration, on vascular endothelial function in Type II diabetes. Endothelial production of nitric oxide (NO) has previously been linked to vascular health. Reactive hyperemia induces a significant increase in plasma nitrite, the proximal metabolite of NO, in healthy subjects, while diabetics have a lower and more variable level of response. Twenty type II diabetics and 20 controls (ages 46–70 years) were taken on a 1.5hr roadway traffic air pollution exposure as passengers. We analyzed plasma nitrite, as a measure of vascular function, using forearm ischemia to elicit a reactive hyperemic response before and after exposure to one ride with and one without filtration of the particle components of pollution. Control subjects displayed a significant increase in plasma nitrite levels during reactive hyperemia. This response was no longer present following exposure to traffic air pollution, but did not vary with whether or not the particle phase was filtered out. Diabetics did not display an increase in nitrite levels following reactive hyperemia. This response was not altered following pollution exposure. These data suggest that components of acute traffic pollution exposure diminish vascular reactivity in non-diabetic individuals. It also confirms that type II diabetics have a preexisting diminished ability to appropriately respond to a vascular challenge, and that traffic pollution exposure does not cause a further measureable acute change in plasma nitrite levels in Type II diabetics. PMID:26656561

  13. Numerical analysis of the double scaling limit in the string type IIB matrix model.

    PubMed

    Horata, S; Egawa, H S

    2001-05-14

    The bosonic IIB matrix model is studied using a numerical method. This model contains the bosonic part of the IIB matrix model conjectured to be a nonperturbative definition of the type IIB superstring theory. The large N scaling behavior of the model is shown performing a Monte Carlo simulation. The expectation value of the Wilson loop operator is measured and the string tension is estimated. The numerical results show the prescription of the double scaling limit. PMID:11384258

  14. Air pollution and inflammation in type 2 diabetes: a mechanism for susceptibility

    PubMed Central

    O'Neill, M S; Veves, A; Sarnat, J A; Zanobetti, A; Gold, D R; Economides, P A; Horton, E S; Schwartz, J

    2007-01-01

    Background Particulate air pollution has been associated with several adverse cardiovascular health outcomes, and people with diabetes may be especially vulnerable. One potential pathway is inflammation and endothelial dysfunction—processes in which cell adhesion molecules and inflammatory markers play important roles. Aim To examine whether plasma levels of soluble intercellular adhesion molecule 1 (ICAM‐1), vascular cell adhesion molecule 1 (VCAM‐1) and von Willebrand factor (vWF) were associated with particle exposure in 92 Boston area residents with type 2 diabetes. Methods Daily average ambient levels of air pollution (fine particles (PM2.5), black carbon (BC) and sulphates) were measured approximately 500 m from the patient examination site and evaluated for associations with ICAM‐1, VCAM‐1 and vWF. Linear regressions were fit to plasma levels of ICAM‐1, VCAM‐1 and vWF, with the particulate pollutant index, apparent temperature, season, age, race, sex, glycosylated haemoglobin, cholesterol, smoking history and body mass index as predictors. Results Air pollutant exposure measures showed consistently positive point estimates of association with the inflammatory markers. Among participants not taking statins and those with a history of smoking, associations between PM2.5, BC and VCAM‐1 were particularly strong. Conclusions These results corroborate evidence suggesting that inflammatory mechanisms may explain the increased risk of air pollution‐associated cardiovascular events among those with diabetes. PMID:17182639

  15. Computational model of collisional-radiative nonequilibrium plasma in an air-driven type laser propulsion

    SciTech Connect

    Ogino, Yousuke; Ohnishi, Naofumi

    2010-05-06

    A thrust power of a gas-driven laser-propulsion system is obtained through interaction with a propellant gas heated by a laser energy. Therefore, understanding the nonequilibrium nature of laser-produced plasma is essential for increasing available thrust force and for improving energy conversion efficiency from a laser to a propellant gas. In this work, a time-dependent collisional-radiative model for air plasma has been developed to study the effects of nonequilibrium atomic and molecular processes on population densities for an air-driven type laser propulsion. Many elementary processes are considered in the number density range of 10{sup 12}/cm{sup 3}<=N<=10{sup 19}/cm{sup 3} and the temperature range of 300 K<=T<=40,000 K. We then compute the unsteady nature of pulsively heated air plasma. When the ionization relaxation time is the same order as the time scale of a heating pulse, the effects of unsteady ionization are important for estimating air plasma states. From parametric computations, we determine the appropriate conditions for the collisional-radiative steady state, local thermodynamic equilibrium, and corona equilibrium models in that density and temperature range.

  16. Evaluation of Annual Performance of Multi-type Air-Conditioners for Buildings

    NASA Astrophysics Data System (ADS)

    Hirota, Masafumi; Watanabe, Choyu; Furukawa, Masahide; Nagamatsu, Katsuaki

    The partial load performance tests of multi-type package air-conditioners for buildings powered by electric motors, the rating cooling performance of which was 56 kW, were carried out by using the air-enthalpy method testing apparatus. The coefficient of performance (COP) and annual energy consumption measured by those tests were closely compared with those estimated from the current calculating method (JIS B 8616:2006). It was found that the performance of the air-conditioner changes depending on the outdoor air temperature and the indoor thermal load. The current calculating method could not reproduce the deteriorations of COP that appeared under the low thermal load condition in both the cooling and heating seasons. As a result it seriously underestimated the annual energy consumption; the error amounted to as large as about 20 % of the measured annual electric power consumption. Based on these results, we have proposed new testing conditions for the performance evaluation and a calculation method of the annual energy consumption that can improve the accuracy of the estimation of the annual energy consumption.

  17. 77 FR 64039 - Limited Approval and Disapproval of Air Quality Implementation Plans; Nevada; Clark County...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-18

    ...EPA is finalizing a limited approval and limited disapproval of revisions to the Clark County portion of the applicable state implementation plan (SIP) for the State of Nevada. The submitted revisions include new and amended rules governing the issuance of permits for stationary sources, including review and permitting of major sources and major modifications under parts C and D of title I of......

  18. 76 FR 31800 - Airworthiness Directives; Viking Air Limited Model DHC-3 (Otter) Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-02

    ... Policies and Procedures (44 FR 11034, February 26, 1979), (3) Will not affect intrastate aviation in Alaska... AFM supplement: ``Airspeed limitation: VMO = 144 MPH for the effective date of this land/ski plane and... of 144 MPH, VMO speed limit for land/ in-service (TIS) after the ski plane and 134 MPH, VMO...

  19. Evaluation of Annual Performance of Multi-type Air-Conditioners for Buildings

    NASA Astrophysics Data System (ADS)

    Watanabe, Choyu; Ohashi, Ei-Ichiro; Nagamatsu, Katsuaki; Nakayama, Hiroshi; Hirota, Masafumi

    In this paper, firstly the results of the partial thermal load performance tests of multi-type air-conditioners for buildings were shown. Tests were conducted by using the air-enthalpy method testing apparatus. Two types of air-conditioners, heat pump driven by electric motors (EHP) and that driven by gas engines (GHP), with a rated cooling capacity of 56 kW were tested. The coefficient of performance (COP) and the annual energy consumption measured by the above mentioned tests were closely compared with those predicted by JIS. In EHP,the measured COP indicates the maximum when the indoor thermal load is about 50% of the rated capacity, while COP in GHP decreases gradually as the thermal load is decreased. Based on these results, we examined the accuracies of COP and the annual energy consumption predicted by JIS. It was found that in both EHP and GHP the current calculating method prescribed in JIS could not duplicate the COP decrease that appeared under the low thermal load conditions. As a result, the annual energy consumption is seriously underestimated by JIS. The prediction errors of the annual energy consumption amounted to about 17% for EHP and 38% for GHP

  20. Miniaturized power limiter metasurface based on Fano-type resonance and Babinet principle.

    PubMed

    Loo, Y L; Wang, H G; Zhang, H; Ong, C K

    2016-09-01

    In this work, we present a miniaturize power limiter, a device with size smaller than that required by the working frequency, made of coupled self-complementary electric inductive-capacitive (CELC) resonator and original electric inductive-capacitive (ELC) structure. We also make use of Babinet principle to ensure both CELC and ELC are resonating at the same frequency. The CELC structure is loaded with a Schottky diode to achieve the effect of a nonlinear power limiter. The constructive interference of CELC and ELC structure produces a new Fano-type resonance peak at a lower frequency. The Fano peak is sharp and able to concentrate electric field at a region between the inner and outer metallic patch of the metastructure, hence enhancing the nonlinear properties of the loaded diode. The Fano peak enhances the maximum isolation of the power limiter due to the local field enhancement at where the diode is loaded. Numerical simulation and experiment are conducted in the S-band frequency to verify the power limiting effect of the device designed and to discuss the formation of Fano peak. The power limiter designed has a maximum isolation of 8.4 dB and a 3-dB isolation bandwidth of 6%. PMID:27607685

  1. Limited significance of curative surgery in Borrmann type IV gastric cancer.

    PubMed

    Kim, Eun Young; Yoo, Han Mo; Song, Kyo Young; Park, Cho Hyun

    2016-07-01

    Borrmann type IV advanced gastric cancer has a poor prognosis. Although surgical resection remains the only hope for a cure, the role of curative surgery is questionable in this type of cancer. This study defined the role of curative surgery in the prognosis of type IV gastric cancer. We analyzed 168 patients with Borrmann type IV undergoing surgery at Seoul St. Mary's Hospital from 1989 to 2010. We categorized the patients into curative (R0) and non-curative (R1, R2, and non-resection) groups. The curative and non-curative groups comprised 88 and 80 patients, respectively. The preoperative predictive value of Borrmann type IV was 50.5, and 8.9 % of the patients had microscopic resection margin involvement. The 3- to 5-year overall survival (OS) of patients in the curative group was significantly higher than that of in the non-curative group (p < 0.001). However, in a multivariate analysis, curability was not a significant predictor of survival (p = 0.187). In the curative group, the most frequent recurrence site was the peritoneum (85.7 %). Most recurrences occurred within 2 years. The role of surgery for Borrmann type IV is quite limited. Such cases have a poor prognosis even after curative surgery. In addition, microscopic resection margin involvement is frequent in type IV cancer because it is difficult to diagnose preoperatively. Therefore, multimodal diagnostic tools and treatment strategies should be developed for Borrmann type IV gastric cancer. PMID:27251378

  2. Identification of aerosol types over an urban site based on air-mass trajectory classification

    NASA Astrophysics Data System (ADS)

    Pawar, G. V.; Devara, P. C. S.; Aher, G. R.

    2015-10-01

    Columnar aerosol properties retrieved from MICROTOPS II Sun Photometer measurements during 2010-2013 over Pune (18°32‧N; 73°49‧E, 559 m amsl), a tropical urban station in India, are analyzed to identify aerosol types in the atmospheric column. Identification/classification is carried out on the basis of dominant airflow patterns, and the method of discrimination of aerosol types on the basis of relation between aerosol optical depth (AOD500 nm) and Ångström exponent (AE, α). Five potential advection pathways viz., NW/N, SW/S, N, SE/E and L have been identified over the observing site by employing the NOAA-HYSPLIT air mass back trajectory analysis. Based on AE against AOD500 nm scatter plot and advection pathways followed five major aerosol types viz., continental average (CA), marine continental average (MCA), urban/industrial and biomass burning (UB), desert dust (DD) and indeterminate or mixed type (MT) have been identified. In winter, sector SE/E, a representative of air masses traversed over Bay of Bengal and Eastern continental Indian region has relatively small AOD (τpλ = 0.43 ± 0.13) and high AE (α = 1.19 ± 0.15). These values imply the presence of accumulation/sub-micron size anthropogenic aerosols. During pre-monsoon, aerosols from the NW/N sector have high AOD (τpλ = 0.61 ± 0.21), and low AE (α = 0.54 ± 0.14) indicating an increase in the loading of coarse-mode particles over Pune. Dominance of UB type in winter season for all the years (i.e. 2010-2013) may be attributed to both local/transported aerosols. During pre-monsoon seasons, MT is the dominant aerosol type followed by UB and DD, while the background aerosols are insignificant.

  3. 76 FR 62605 - Airworthiness Directives; Viking Air Limited Model DHC-3 (Otter) Airplanes With Supplemental Type...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    ... . SUPPLEMENTARY INFORMATION: Airworthiness Directive 2011-12-02, Amendment 39-16709 (76 FR 31800, June 2, 2011... 2, 2011, AD 2011-12-02; Amendment 39-16709 (76 FR 31800, June 2, 2011), is corrected as follows: On...-02; Amendment 39- 16709 (76 FR 31800, June 2, 2011), on page 31802, paragraphs (e) and (f)(2) of...

  4. 75 FR 70106 - Airworthiness Directives; Viking Air Limited (Type Certificate Previously Held by Bombardier, Inc...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-17

    ... NPRM was published in the Federal Register on July 23, 2010, (75 FR 43092). That NPRM proposed to... Procedures (44 FR 11034, February 26, 1979); and 3. Will not have a significant economic impact, positive or... 2009-NM-236-AD; Amendment 39-16510; AD 2010-23-21] RIN 2120-AA64 Airworthiness Directives; Viking...

  5. 76 FR 53633 - Airworthiness Directives; Viking Air Limited (Type Certificate No. A-815 Formerly Held by...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-29

    ... as of March 31, 2011 (76 FR 10220, February 24, 2011). ADDRESSES: For information about the revisions...) to amend 14 CFR part 39 to supersede AD 2011-05-02, Amendment 39-16611 (76 FR 10220, February 24..., 2011 (76 FR 34011). That NPRM proposed to retain all of the requirements of AD 2011-05-02 and...

  6. 75 FR 75932 - Airworthiness Directives; Viking Air Limited (Type Certificate No. A-815 Formerly Held by...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-07

    ... above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. For information about...., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory... ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), (3)...

  7. Geographical and climatic limits of needle types of one- and two-needled pinyon pines

    USGS Publications Warehouse

    Cole, K.L.; Fisher, J.; Arundel, S.T.; Cannella, J.; Swift, S.

    2008-01-01

    Aim: The geographical extent and climatic tolerances of one- and two-needled pinyon pines (Pinus subsect. Cembroides) are the focus of questions in taxonomy, palaeoclimatology and modelling of future distributions. The identification of these pines, traditionally classified by one- versus two-needled fascicles, is complicated by populations with both one- and two-needled fascicles on the same tree, and the description of two more recently described one-needled varieties: the fallax-type and californiarum-type. Because previous studies have suggested correlations between needle anatomy and climate, including anatomical plasticity reflecting annual precipitation, we approached this study at the level of the anatomy of individual pine needles rather than species. Location: Western North America. Methods: We synthesized available and new data from field and herbarium collections of needles to compile maps of their current distributions across western North America. Annual frequencies of needle types were compared with local precipitation histories for some stands. Historical North American climates were modelled on a c. 1-km grid using monthly temperature and precipitation values. A geospatial model (ClimLim), which analyses the effect of climate-modulated physiological and ecosystem processes, was used to rank the importance of seasonal climate variables in limiting the distributions of anatomical needle types. Results: The pinyon needles were classified into four distinct types based upon the number of needles per fascicle, needle thickness and the number of stomatal rows and resin canals. The individual needles fit well into four categories of needle types, whereas some trees exhibit a mixture of two needle types. Trees from central Arizona containing a mixture of Pinus edulis and fallax-type needles increased their percentage of fallax-type needles following dry years. All four needle types occupy broader geographical regions with distinctive precipitation regimes

  8. Effects of percentage of blockage and flameholder downstream counterbores on lean combustion limits of premixed, prevaporized propane-air mixture

    NASA Technical Reports Server (NTRS)

    Fernandez, M. A. B.

    1983-01-01

    Lean combustion limits were determined for a premixed prevaporized propane air mixture with flat plate flame stabilizers. Experiments were conducted in a constant area flame tube combustor utilizing flameholders of varying percentages of blockage and downstream counterbores. Combustor inlet air velocity at ambient conditions was varied from 4 to 9 meters per second. Flameholders with a center hole and four half holes surrounding it were tested with 63, 73, and 85 percent blockage and counterbore diameters of 112 and 125 percent of the thru hole diameter, in addition to the no counterbore configuration. Improved stability was obtained by using counterbore flameholders and higher percentages of blockage. Increases in mixture velocity caused the equivalence ratio at blowout to increase in all cases.

  9. 42 CFR 84.156 - Airflow resistance test; Type C supplied-air respirator, demand class; minimum requirements.

    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 respirator, demand class; minimum requirements. 84.156 Section 84.156 Public Health PUBLIC HEALTH SERVICE... C supplied-air respirator, demand class; minimum requirements. (a) Inhalation resistance shall...

  10. 42 CFR 84.156 - Airflow resistance test; Type C supplied-air respirator, demand class; minimum requirements.

    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 respirator, demand class; minimum requirements. 84.156 Section 84.156 Public Health PUBLIC HEALTH SERVICE... C supplied-air respirator, demand class; minimum requirements. (a) Inhalation resistance shall...

  11. 42 CFR 84.156 - Airflow resistance test; Type C supplied-air respirator, demand class; minimum requirements.

    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 respirator, demand class; minimum requirements. 84.156 Section 84.156 Public Health PUBLIC HEALTH SERVICE... C supplied-air respirator, demand class; minimum requirements. (a) Inhalation resistance shall...

  12. 42 CFR 84.156 - Airflow resistance test; Type C supplied-air respirator, demand class; minimum requirements.

    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 respirator, demand class; minimum requirements. 84.156 Section 84.156 Public Health PUBLIC HEALTH SERVICE... C supplied-air respirator, demand class; minimum requirements. (a) Inhalation resistance shall...

  13. Combustion rate limits of hydrogen plus hydrocarbon fuel: Air diffusion flames from an opposed jet burner technique

    NASA Technical Reports Server (NTRS)

    Pellett, Gerald L.; Guerra, Rosemary; Wilson, Lloyd G.; Reeves, Ronald N.; Northam, G. Burton

    1987-01-01

    Combustion of H2/hydrocarbon (HC) fuel mixtures may be considered in certain volume-limited supersonic airbreathing propulsion applications. Effects of HC addition to H2 were evaluated, using a recent argon-bathed, coaxial, tubular opposed jet burner (OJB) technique to measure the extinction limits of counterflow diffusion flames. The OJB flames were formed by a laminar jet of (N2 and/or HC)-diluted H2 mixture opposed by a similar jet of air at ambient conditions. The OJB data, derived from respective binary mixtures of H2 and methane, ethylene, or propane HCs, were used to characterize BLOWOFF and RESTORE. BLOWOFF is a sudden breaking of the dish-shaped OJB flame to a stable torus or ring shape, and RESTORE marks sudden restoration of the central flame by radial inward flame propagation. BLOWOFF is a measure of kinetically-limited flame reactivity/speed under highly stretched, but relatively ideal impingement flow conditions. RESTORE measures inward radial flame propagation rate, which is sensitive to ignition processes in the cool central core. It is concluded that relatively small molar amounts of added HC greatly reduce the reactivity characteristics of counterflow hydrogen-air diffusion flames, for ambient initial conditions.

  14. AMI 15 GHz upper limits for the nearby Type Ia supernova SN 2016coj

    NASA Astrophysics Data System (ADS)

    Mooley, K. P.; Fender, R. P.; Cantwell, T.; Titterington, D.; Saunders, R.; Carey, S.; Hickish, J.; Perrott, Y. C.; Razavi-Ghods, N.; Scott, P.; Grainge, K.; Scaife, A.

    2016-06-01

    We observed the type Ia supernova SN 2016coj in NGC 4125 (Zheng et al., ATel #9095; d=19Mpc; discovery date 2016 May 28.18) with the AMI Large Array at 15 GHz. We detected a fading source (later found to be a chance coincidence; see below) at the location of the supernova on 2016 Jun 03.86, Jun 05.89 and Jun 09.76 UT, following which we triggered the Jansky VLA. The VLA observations, carried out between 2-18 GHz on Jun 11.07 UT, gave 3sigma upper limits of ~60 uJy at S, C, X and Ku bands.

  15. Bright but slow - Type II supernovae from OGLE-IV - implications for magnitude-limited surveys

    NASA Astrophysics Data System (ADS)

    Poznanski, D.; Kostrzewa-Rutkowska, Z.; Wyrzykowski, L.; Blagorodnova, N.

    2015-05-01

    We study a sample of 11 Type II supernovae (SNe) discovered by the OGLE-IV survey. All objects have well-sampled I-band light curves, and at least one spectrum. We find that two or three of the 11 SNe have a declining light curve, and spectra consistent with other SNe II-L, while the rest have plateaus that can be as short as 70 d, unlike the 100 d typically found in nearby galaxies. The OGLE SNe are also brighter, and show that magnitude-limited surveys find SNe that are different than usually found in nearby galaxies. We discuss this sample in the context of understanding Type II SNe as a class and their suggested use as standard candles.

  16. [Usefulness and limitations of basal insulin replacement in type 2 diabetes].

    PubMed

    Hirata, Erina; Ohmori, Kazuno; Nagai, Sou

    2015-03-01

    In the earlier stage of type 2 diabetes, the disease can be managed by life-style modification with or without oral antidiabetic agents. However, as the disease progress, most patients eventually require insulin treatment to maintain good glycemic/control. Optimal insulin therapy should mimic the normal physiologic secretory pattern. As for ideal basal insulin, to maintain desirable pre-prandial glucose levels, duration of action should be long enough, profiles such as flat time-action and less day-to-day variation would be mandatory. This article discusses the usefulness and limitations of basal insulin therapy in type 2 diabetes comparing NPH insulin, insulin detemir, insulin glargin and insulin degludec. PMID:25812373

  17. Limited open repair of ruptured Achilles tendons with Bunnel-type sutures.

    PubMed

    Park, H G; Moon, D H; Yoon, J M

    2001-12-01

    A new method of repairing Achilles tendons, which uses a small medial skin incision with a Bunnel-type suture, was performed on 14 patients, and the clinical results were found satisfying. In order to restore the Achilles tendon to its original length, restore tensile strength in the suture site, and minimize injury to the sural nerve, an operative procedure has been devised which uses a limited open repair with a Bunnel-type suture. We followed 14 patients who had undergone the new procedure for a mean interval of 26 months after the injury. They returned to work in six weeks and to playing sports in 25 weeks. There were no cases of late rerupture nor injuries to the sural nerve. This technique approximated the preinjury length and resting tension of the musculo-tendinous apparatus and minimized sural nerve injury. PMID:11783926

  18. 75 FR 77798 - Approval and Promulgation of Air Quality Implementation Plans; Delaware; Limiting Emissions of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-14

    ... Emissions of Volatile Organic Compounds From Portable Fuel Containers AGENCY: Environmental Protection...'s regulation for Volatile Organic Compounds (VOC) from Consumer and Commercial Products, Section 3.0... Implementation Plans; Delaware; Limiting Emissions of Volatile Organic Compounds from Portable Fuel...

  19. DEVELOPMENT OF THE HS99 AIR TRANSPORT TYPE A FISSILE PACKAGE

    SciTech Connect

    Blanton, P.; Eberl, K.

    2012-07-10

    An air-transport Type A Fissile radioactive shipping package for the transport of special form uranium sources has been developed by the Savannah River National Laboratory (SRNL) for the Department of Homeland Security. The Package model number is HS99 for Homeland Security Model 99. This paper presents the major design features of the HS99 and highlights engineered materials necessary for meeting the design requirements for this light-weight Type AF packaging. A discussion is provided demonstrating how the HS99 complies with the regulatory safety requirements of the Nuclear Regulatory Commission. The paper summarizes the results of structural testing to specified in 10 CFR 71 for Normal Conditions of Transport and Hypothetical Accident Conditions events. Planned and proposed future missions for this packaging are also addressed.

  20. Compressed air demand-type firefighter's breathing system, volume 1. [design analysis and performance tests

    NASA Technical Reports Server (NTRS)

    Sullivan, J. L.

    1975-01-01

    The commercial availability of lightweight high pressure compressed air vessels has resulted in a lightweight firefighter's breathing apparatus. The improved apparatus, and details of its design and development are described. The apparatus includes a compact harness assembly, a backplate mounted pressure reducer assembly, a lightweight bubble-type facemask with a mask mounted demand breathing regulator. Incorporated in the breathing regulator is exhalation valve, a purge valve and a whistle-type low pressure warning that sounds only during inhalation. The pressure reducer assembly includes two pressure reducers, an automatic transfer valve and a signaling device for the low pressure warning. Twenty systems were fabricated, tested, refined through an alternating development and test sequence, and extensively examined in a field evaluation program. Photographs of the apparatus are included.

  1. Progress Toward a Global, EOS-Era Aerosol Air Mass Type Climatology

    NASA Technical Reports Server (NTRS)

    Kahn, Ralph A.

    2012-01-01

    The MISR and MODIS instruments aboard the NASA Earth Observing System's Terra Satellite have been collecting data containing information about the state of Earth's atmosphere and surface for over eleven years. Data from these instruments have been used to develop a global, monthly climatology of aerosol amount that is widely used as a constraint on climate models, including those used for the 2007 IPCC assessment report. The next frontier in assessing aerosol radiative forcing of climate is aerosol type, and in particular, the absorption properties of major aerosol air masses. This presentation will focus on the prospects for constraining aerosol type globally, and the steps we are taking to apply a combination of satellite and suborbital data to this challenge.

  2. Interaction of temperature, humidity, driver preferences, and refrigerant type on air conditioning compressor usage.

    PubMed

    Levine, C; Younglove, T; Barth, M

    2000-10-01

    Recent studies have shown large increases in vehicle emissions when the air conditioner (AC) compressor is engaged. Factors that affect the compressor-on percentage can have a significant impact on vehicle emissions and can also lead to prediction errors in current emissions models if not accounted for properly. During 1996 and 1997, the University of California, Riverside, College of Engineering-Center for Environmental Research and Technology (CE-CERT) conducted a vehicle activity study for the California Air Resources Board (CARB) in the Sacramento, CA, region. The vehicles were randomly selected from all registered vehicles in the region. As part of this study, ten vehicles were instrumented to collect AC compressor on/off data on a second-by-second basis in the summer of 1997. Temperature and humidity data were obtained and averaged on an hourly basis. The ten drivers were asked to complete a short survey about AC operational preferences. This paper examines the effects of temperature, humidity, refrigerant type, and driver preferences on air conditioning compressor activity. Overall, AC was in use in 69.1% of the trips monitored. The compressor was on an average of 64% of the time during the trips. The personal preference settings had a significant effect on the AC compressor-on percentage but did not interact with temperature. The refrigerant types, however, exhibited a differential response across temperature, which may necessitate separate modeling of the R12 refrigerant-equipped vehicles from the R134A-equipped vehicles. It should be noted that some older vehicles do get retrofitted with new compressors that use R134A; however, none of the vehicles in this study had been retrofitted. PMID:11288304

  3. Investigation into the aerodynamic processes of air treatment using a plate-type biofilter.

    PubMed

    Baltrėnas, Pranas; Kleiza, Jonas; Idzelis, Raimondas Leopoldas

    2016-03-01

    The research conducted has involved a laboratory stand of a plate-type air treatment biofilter with a capillary system for humidifying packing material composed of polymer plates vertically arranged next to each other and producing a capillary effect of humidification. The pattern of arranging the plates has sufficiently large spaces (6 mm), and therefore the use of the plate-type structure decreases the aerodynamic resistance of the device. Slightly pressed slabs attached on both sides of the plates are made of heat-treated wood fibre, to increase the longevity of which, wood waste has been heat-treated in the steam explosion reactor under the pressure of 32 bars and a temperature of 235°C. This is the method for changing the molecular structure of wood, which stops the decay of wood fibre in a humid environment and thus increases the life span of biofilter plates. The research performed has disclosed that, under the application of the above introduced structure of the biofilter, the aerodynamic resistance of the biofilter reaches 1 ÷ 5 Pa when the rate of the air flow passing through the device makes 0.08 m/s. For evaluating the reliability of the obtained results, the theoretical model has been applied. PMID:26207569

  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, 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...

  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, 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...

  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, 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...

  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, 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...

  9. Runge-Kutta discontinuous Galerkin method using a new type of WENO limiters on unstructured meshes

    NASA Astrophysics Data System (ADS)

    Zhu, Jun; Zhong, Xinghui; Shu, Chi-Wang; Qiu, Jianxian

    2013-09-01

    In this paper we generalize a new type of limiters based on the weighted essentially non-oscillatory (WENO) finite volume methodology for the Runge-Kutta discontinuous Galerkin (RKDG) methods solving nonlinear hyperbolic conservation laws, which were recently developed in [32] for structured meshes, to two-dimensional unstructured triangular meshes. The key idea of such limiters is to use the entire polynomials of the DG solutions from the troubled cell and its immediate neighboring cells, and then apply the classical WENO procedure to form a convex combination of these polynomials based on smoothness indicators and nonlinear weights, with suitable adjustments to guarantee conservation. The main advantage of this new limiter is its simplicity in implementation, especially for the unstructured meshes considered in this paper, as only information from immediate neighbors is needed and the usage of complicated geometric information of the meshes is largely avoided. Numerical results for both scalar equations and Euler systems of compressible gas dynamics are provided to illustrate the good performance of this procedure.

  10. Quantum-limited phase-matching effect in a {Lambda}-type laser system

    SciTech Connect

    Yu Deshui; Chen Jingbiao

    2011-06-15

    The theory of a quantum-limited phase-matching effect in a {Lambda}-type lasing system is studied in detail based on the quantum Langevin approach. Two quasimonochromatic fields are directly generated based on two lasing transitions. We find that the coherence between two lasers can well exceed the linewidth of either laser field. This result denotes that two field phases match each other although either laser field has a high phase fluctuation. Unlike the phase-matching effect based on atomic absorption, the final coherence between two laser fields here is not limited by saturation broadening, and the higher laser intensities lead to a higher coherence. Additionally, based on a linear stability analysis, we find that the instability of the field steady state can substantially restrict the occurrence of this phase-matching effect in the bad-cavity limit for a high pump rate. We also discuss the spectrum of amplitude fluctuations of output fields, and the result shows that the squeezing of amplitude fluctuations at low frequencies for a single field oscillating inside the cavity is damaged in the case of two fields oscillating.

  11. Upper limits on the luminosity of the progenitor of Type Ia supernova SN 2014J

    NASA Astrophysics Data System (ADS)

    Nielsen, M. T. B.; Gilfanov, M.; Bogdán, Á.; Woods, T. E.; Nelemans, G.

    2014-08-01

    We analysed archival data of Chandra pre-explosion observations of the position of SN 2014J in M82. No X-ray source at this position was detected in the data, and we calculated upper limits on the luminosities of the progenitor. These upper limits allow us to firmly rule out an unobscured supersoft X-ray source progenitor with a photospheric radius comparable to the radius of white dwarf near the Chandrasekhar mass (˜1.38 M⊙) and mass accretion rate in the interval where stable nuclear burning can occur. However, due to a relatively large hydrogen column density implied by optical observations of the supernova, we cannot exclude a supersoft source with lower temperatures, kT ≲ 70 eV. We find that the supernova is located in the centre of a large structure of soft diffuse emission, about 200 pc across. The mass, ˜3 × 104 M⊙ and short cooling time of the gas, τcool ˜ 8 Myr, suggest that it is a supernova-inflated superbubble, associated with the region of recent star formation. If SN 2014J is indeed located inside the bubble, it likely belongs to the prompt population of Type Ia supernovae, with a delay time as short as ˜50 Myr. Finally, we analysed the one existing post-supernova Chandra observation and placed upper limit of ˜(1-2) × 1037 erg s-1 on the X-ray luminosity of the supernova itself.

  12. Vibration amplitude and induced temperature limitation of high power air-borne ultrasonic transducers.

    PubMed

    Saffar, Saber; Abdullah, Amir

    2014-01-01

    The acoustic impedances of matching layers, their internal loss and vibration amplitude are the most important and influential parameters in the performance of high power airborne ultrasonic transducers. In this paper, the optimum acoustic impedances of the transducer matching layers were determined by using a genetic algorithm, the powerful tool for optimizating domain. The analytical results showed that the vibration amplitude increases significantly for low acoustic impedance matching layers. This enhancement is maximum and approximately 200 times higher for the last matching layer where it has the same interface with the air than the vibration amplitude of the source, lead zirconate titanate-pizo electric while transferring the 1 kW is desirable. This large amplitude increases both mechanical failure and temperature of the matching layers due to the internal loss of the matching layers. It has analytically shown that the temperature in last matching layer with having the maximum vibration amplitude is high enough to melt or burn the matching layers. To verify suggested approach, the effect of the amplitude of vibration on the induced temperature has been investigated experimentally. The experimental results displayed good agreement with the theoretical predictions. PMID:23664304

  13. An upper limit on the contribution of accreting white dwarfs to the type Ia supernova rate.

    PubMed

    Gilfanov, Marat; Bogdán, Akos

    2010-02-18

    There is wide agreement that type Ia supernovae (used as standard candles for cosmology) are associated with the thermonuclear explosions of white dwarf stars. The nuclear runaway that leads to the explosion could start in a white dwarf gradually accumulating matter from a companion star until it reaches the Chandrasekhar limit, or could be triggered by the merger of two white dwarfs in a compact binary system. The X-ray signatures of these two possible paths are very different. Whereas no strong electromagnetic emission is expected in the merger scenario until shortly before the supernova, the white dwarf accreting material from the normal star becomes a source of copious X-rays for about 10(7) years before the explosion. This offers a means of determining which path dominates. Here we report that the observed X-ray flux from six nearby elliptical galaxies and galaxy bulges is a factor of approximately 30-50 less than predicted in the accretion scenario, based upon an estimate of the supernova rate from their K-band luminosities. We conclude that no more than about five per cent of type Ia supernovae in early-type galaxies can be produced by white dwarfs in accreting binary systems, unless their progenitors are much younger than the bulk of the stellar population in these galaxies, or explosions of sub-Chandrasekhar white dwarfs make a significant contribution to the supernova rate. PMID:20164924

  14. Chronic air-flow limitation does not increase respiratory epithelial permeability assessed by aerosolized solute, but smoking does

    SciTech Connect

    Huchon, G.J.; Russell, J.A.; Barritault, L.G.; Lipavsky, A.; Murray, J.F.

    1984-09-01

    To determine the separate influences of smoking and severe air-flow limitation on aerosol deposition and respiratory epithelial permeability, we studied 26 normal nonsmokers, 12 smokers without airway obstruction, 12 nonsmokers with chronic obstructive pulmonary disease (COPD), and 11 smokers with COPD. We aerosolized 99mTc-labeled diethylene triamine pentaacetic acid to particles approximately 1 micron activity median aerodynamic diameter. Levels of radioactivity were plotted semilogarithmically against time to calculate clearance as percent per minute. The distribution of radioactivity was homogeneous in control subjects and in smokers, but patchy in both groups with COPD. No difference was found between clearances of the control group (1.18 +/- 0.31% min-1), and nonsmoker COPD group (1.37 +/- 0.82% min-1), whereas values in smokers without COPD (4.00 +/- 1.70% min-1) and smokers with COPD (3.62 +/- 2.88% min-1) were significantly greater than in both nonsmoking groups. We conclude that (1) small particles appear to deposit peripherally, even with severe COPD; (2) respiratory epithelial permeability is normal in nonsmokers with COPD; (3) smoking increases permeability by a mechanism unrelated to air-flow limitation.

  15. Exploring the role of the sampler housing in limiting uptake of semivolatile organic compounds in passive air samplers.

    PubMed

    Zhang, Xianming; Hoang, Michelle; Lei, Ying D; Wania, Frank

    2015-12-01

    Passive air samplers (PASs) are simple, versatile devices that are increasingly used to determine the concentrations of semivolatile organic compounds (SVOCs) in the atmosphere. Using PAS and interpreting PAS-derived data with confidence requires a detailed understanding of the factors that control the uptake kinetics. A number of experiments were aimed at clarifying the role that the housing has in limiting the uptake of SVOCs in a PAS. Specifically, we quantified the gradient in the amount of polychlorinated biphenyls (PCBs) accumulated in XAD-filled mesh cylinders with increasing distance from the PAS housing's opening. That gradient was non-existent in an artificially ventilated housing (i.e. different segments of a cylinder contained the same amount of PCBs), minor during outdoor deployments (i.e. the bottom third of the cylinder sampled approximately 20% more PCBs than the top third), and strong during indoor deployments (i.e. the bottom third of the cylinder sampled twice the amount sampled by the top third). This is consistent with the thickness of the air boundary layer surrounding the XAD-resin increasing with increasing distance from the housing's opening and decreasing with increasing air turbulence. An experiment with housings absorbing different amounts of sunlight revealed that heat-induced convection has a minor effect on the gradient within the mesh cylinder and on the total amount of accumulated PCB. Similarly, this gradient and the total amount sorbed was also not influenced by the number of XAD-filled mesh cylinders placed within a housing as long as they were deployed outdoors. However, if four mesh cylinders were placed in one housing in a calm indoor setting, the top third of the mesh cylinders was notably starved of PCBs, suggestive of an air concentration gradient within the sampler housing. PMID:26598925

  16. Fatigue properties of type 316LN stainless steel in air and mercury

    NASA Astrophysics Data System (ADS)

    Strizak, J. P.; Tian, H.; Liaw, P. K.; Mansur, L. K.

    2005-08-01

    An extensive fatigue testing program on 316LN stainless steel was recently carried out to support the design of the mercury target container for the spallation neutron source (SNS) that is currently under construction at the Oak Ridge National Laboratory in the United States. The major objective was to determine the effects of mercury on fatigue behavior. The S- N fatigue behavior of 316LN stainless steel is characterized by a family of bilinear fatigue curves which are dependent on frequency, environment, mean stress and cold work. Generally, fatigue life increases with decreasing stress and levels off in the high cycle region to an endurance limit below which the material will not fail. For fully reversed loading as well as tensile mean stress loading conditions mercury had no effect on endurance limit. However, at higher stresses a synergistic relationship between mercury and cyclic loading frequency was observed at low frequencies. As expected, fatigue life decreased with decreasing frequency, but the response was more pronounced in mercury compared with air. As a result of liquid metal embrittlement (LME), fracture surfaces of specimens tested in mercury showed widespread brittle intergranular cracking as opposed to typical transgranular cracking for specimens tested in air. For fully reversed loading (zero mean stress) the effect of mercury disappeared as frequency increased to 10 Hz. For mean stress conditions with R-ratios of 0.1 and 0.3, LME was still evident at 10 Hz, but at 700 Hz the effect of mercury had disappeared ( R = 0.1). Further, for higher R-ratios (0.5 and 0.75) fatigue curves for 10 Hz showed no environmental effect. Finally, cold working (20%) increased tensile strength and hardness, and improved fatigue resistance. Fatigue behavior at 10 and 700 Hz was similar and no environmental effect was observed.

  17. Limits to the symmetry of a Mach-Zehnder-type atom interferometer

    NASA Astrophysics Data System (ADS)

    Gillot, P.; Cheng, B.; Merlet, S.; Pereira Dos Santos, F.

    2016-01-01

    Owing to the use of a symmetrization π pulse at the middle of their laser sequences, Mach-Zehnder-type atom interferometers are insensitive to clocks shifts and Doppler shifts, if constant, but to changes in these quantities, which makes them accurate and sensitive inertial-force sensors. However, variations of the Raman laser coupling between laser pulses restore a parasitic sensitivity to the Doppler shift. This effect, which sets a limit to the symmetry of the interferometer, is quantitatively evaluated here as a function of the experimental parameters, in the case of an atom gravimeter experiment, and compared to expectations. We show in particular that velocity-distribution asymmetries lead to parasitic phase shifts that can compromise the accuracy and long-term stability of the gravity measurement in the low 10-9g range.

  18. Inherent limitations of nondestructive chlorophyll meters: a comparison of two types of meters

    NASA Technical Reports Server (NTRS)

    Monje, O. A.; Bugbee, B.

    1992-01-01

    Two types of nondestructive chlorophyll meters were compared with a standard, destructive chlorophyll measurement technique. The nondestructive chlorophyll meters were 1) a custom built, single-wavelength meter, and 2) the recently introduced, dual-wavelengh, chlorophyll meter from Minolta (model SPAD-502). Data from both meters were closely correlated with destructive measurements of chlorophyll (r2 = 0.90 and 0.93; respectively) for leaves with chlorophyll concentrations ranging from 100 to 600 mg m-2, but both meters consistently overestimated chlorophyll outside this range. Although the dual-wavelength meter was slightly more accurate than the single-wavelength meter (higher r2), the light-scattering properties of leaf cells and the nonhomogeneous distribution of chlorophyll in leaves appear to limit the ability of all meters to estimate in vivo chlorophyll concentration.

  19. Inherent limitations of nondestructive chlorophyll meters: a comparison of two types of meters.

    PubMed

    Monje, O A; Bugbee, B

    1992-01-01

    Two types of nondestructive chlorophyll meters were compared with a standard, destructive chlorophyll measurement technique. The nondestructive chlorophyll meters were 1) a custom built, single-wavelength meter, and 2) the recently introduced, dual-wavelengh, chlorophyll meter from Minolta (model SPAD-502). Data from both meters were closely correlated with destructive measurements of chlorophyll (r2 = 0.90 and 0.93; respectively) for leaves with chlorophyll concentrations ranging from 100 to 600 mg m-2, but both meters consistently overestimated chlorophyll outside this range. Although the dual-wavelength meter was slightly more accurate than the single-wavelength meter (higher r2), the light-scattering properties of leaf cells and the nonhomogeneous distribution of chlorophyll in leaves appear to limit the ability of all meters to estimate in vivo chlorophyll concentration. PMID:11537728

  20. Swift X-Ray Upper Limits on Type Ia Supernova Environments

    NASA Technical Reports Server (NTRS)

    Russell, B. R.; Immler, S.

    2012-01-01

    We have considered 53 Type Ia supernovae (SNe Ia) observed by the Swift X-Ray Telescope. None of the SNe Ia are individually detected at any time or in stacked images. Using these data and assuming that the SNe Ia are a homogeneous class of objects, we have calculated upper limits to the X-ray luminosity (0.2-10 keV) and mass-loss rate of L(sub 0.2-10) < 1.7 X 10(exp 38) erg/s and M(dot) < l.l X 10(exp -6) solar M/ yr x (V(sub w))/(10 km/s), respectively. The results exclude massive or evolved stars as the companion objects in SN Ia progenitor systems, but allow the possibility of main sequence or small stars, along with double degenerate systems consisting of two white dwarfs, consistent with results obtained at other wavelengths (e.g., UV, radio) in other studies.

  1. [Unusual and fatal type of burn injury: hot air sauna burn].

    PubMed

    García-Tutor, E; Koljonen, V

    2007-01-01

    Sauna bathing is a popular recreational activity in Finland and is generally considered safe even for pregnant women and patients suffering from heart problems; but mixing alcohol with sauna bathing can be hazardous. In the normal Finnish recreational sauna the temperature is usually between 80 and 90 degrees C. A wide variety of burn injuries, in all age groups, are related to sauna bathing; scalds and contact burns account for over 85% while hot air, steam and flame burns for only 15%. Dehydration in patients under the influence of alcohol heightens the risk of hypotension which impairs skin blood circulation. This increased warming of the skin is an effect that is more marked on the outer and upper parts of the body exposed to hot air. Such patients require intensive care on admission: fluid replacement according to the Parkland formula, forced diuresis and immediate correction of acidosis and myoglobinuria. These patients have significant rhabdomyolysis on admission. The best predictor of survival is the creatine kinase level on the second post-injury day. CT scans are necessary to diagnose the underlying conditions of unconsciousness. The necrotic area extends to subcutaneous fat tissue and even to the underlying muscles. The level of excision is typically fascial and, in some areas, layers of the muscle must be removed. Owing to the popularity of sauna bathing throughout the world, it is important to know the extent of damage in this type of injury, in order not to underestimate the severity of such lesions. PMID:17886710

  2. Impact of bicycle route type on exposure to traffic-related air pollution.

    PubMed

    MacNaughton, Piers; Melly, Steven; Vallarino, Jose; Adamkiewicz, Gary; Spengler, John D

    2014-08-15

    Cyclists are exposed to traffic-related air pollution (TRAP) during their commutes due to their proximity to vehicular traffic. Two of the main components of TRAP are black carbon (BC) and nitrogen dioxide (NO2), which have both been causally associated with increased mortality. To assess the impact of cyclists' exposure to TRAP, a battery-powered mobile monitoring station was designed to sample air pollutants along five bike routes in Boston, Massachusetts. The bike routes were categorized into three types: bike paths, which are separated from vehicle traffic; bike lanes, which are adjacent to traffic; and designated bike lanes, which are shared traffic lanes for buses and cyclists. Bike lanes were found to have significantly higher concentrations of BC and NO2 than bike paths in both adjusted and unadjusted generalized linear models. Higher concentrations were observed in designated bike lanes than bike paths; however, this association was only significant for NO2. After adjusting for traffic density, background concentration, and proximity to intersections, bike lanes were found to have concentrations of BC and NO2 that were approximately 33% higher than bike paths. Distance from the road, vegetation barriers, and reduced intersection density appear to influence these variations. These findings suggest that cyclists can reduce their exposure to TRAP during their commute by using bike paths preferentially over bike lanes regardless of the potential increase of traffic near these routes. PMID:24840278

  3. Air-water ‘tornado’-type microwave plasmas applied for sugarcane biomass treatment

    NASA Astrophysics Data System (ADS)

    Bundaleska, N.; Tatarova, E.; Dias, F. M.; Lino da Silva, M.; Ferreira, C. M.; Amorim, J.

    2014-02-01

    The production of cellulosic ethanol from sugarcane biomass is an attractive alternative to the use of fossil fuels. Pretreatment is needed to separate the cellulosic material, which is packed with hemicellulose and lignin in cell wall of sugarcane biomass. A microwave ‘tornado’-type air-water plasma source operating at 2.45 GHz and atmospheric pressure has been applied for this purpose. Samples of dry and wet biomass (˜2 g) have been exposed to the late afterglow plasma stream. The experiments demonstrate that the air-water highly reactive plasma environment provides a number of long-lived active species able to destroy the cellulosic wrapping. Scanning electron microscopy has been applied to analyse the morphological changes occurring due to plasma treatment. The effluent gas streams have been analysed by Fourier-transform infrared spectroscopy (FT-IR). Optical emission spectroscopy and FT-IR have been applied to determine the gas temperature in the discharge and late afterglow plasma zones, respectively. The optimal range of the operational parameters is discussed along with the main active species involved in the treatment process. Synergistic effects can result from the action of singlet O2(a 1Δg) oxygen, NO2, nitrous acid HNO2 and OH hydroxyl radical.

  4. Coastal recirculation potential affecting air pollutants in Portugal: The role of circulation weather types

    NASA Astrophysics Data System (ADS)

    Russo, Ana; Gouveia, Célia; Levy, Ilan; Dayan, Uri; Jerez, Sonia; Mendes, Manuel; Trigo, Ricardo

    2016-06-01

    Coastal zones are under increasing development and experience air pollution episodes regularly. These episodes are often related to peaks in local emissions from industry or transportation, but can also be associated with regional transport from neighbour urban areas influenced by land-sea breeze recirculation. This study intends to analyze the relation between circulation weather patterns, air mass recirculation and pollution levels in three coastal airsheds of Portugal (Lisbon, Porto and Sines) based on the application of an objective quantitative measure of potential recirculation. Although ventilation events have a dominant presence throughout the studied 9-yrs period on all the three airsheds, recirculation and stagnation conditions occur frequently. The association between NO2, SO2 and O3 levels and recirculation potential is evident during summer months. Under high average recirculation potential and high variability, NO2 and SO2 levels are higher for the three airsheds, whilst for O3 each airshed responds differently. This indicates a high heterogeneity among the three airsheds in (1) the type of emission - traffic or industry - prevailing for each contaminant, and (2) the response to the various circulation weather patterns and recirculation situations. Irrespectively of that, the proposed methodology, based on iterative K-means clustering, allows to identify which prevailing patterns are associated with high recirculation potential, having the advantage of being applicable to any geographical location.

  5. Implicit high-order discontinuous Galerkin method with HWENO type limiters for steady viscous flow simulations

    NASA Astrophysics Data System (ADS)

    Jiang, Zhen-Hua; Yan, Chao; Yu, Jian

    2013-08-01

    Two types of implicit algorithms have been improved for high order discontinuous Galerkin (DG) method to solve compressible Navier-Stokes (NS) equations on triangular grids. A block lower-upper symmetric Gauss-Seidel (BLU-SGS) approach is implemented as a nonlinear iterative scheme. And a modified LU-SGS (LLU-SGS) approach is suggested to reduce the memory requirements while retain the good convergence performance of the original LU-SGS approach. Both implicit schemes have the significant advantage that only the diagonal block matrix is stored. The resulting implicit high-order DG methods are applied, in combination with Hermite weighted essentially non-oscillatory (HWENO) limiters, to solve viscous flow problems. Numerical results demonstrate that the present implicit methods are able to achieve significant efficiency improvements over explicit counterparts and for viscous flows with shocks, and the HWENO limiters can be used to achieve the desired essentially non-oscillatory shock transition and the designed high-order accuracy simultaneously.

  6. SOME CONSTRAINTS ON THE LOWER MASS LIMIT FOR DOUBLE-DEGENERATE PROGENITORS OF TYPE Ia SUPERNOVAE

    SciTech Connect

    Chen, X.; Han, Z.

    2012-08-10

    Recent theoretical and observational studies both argue that the merging of double carbon-oxygen white dwarfs (WDs) is responsible for at least some Type Ia supernovae (SNe Ia). Previous (standard) studies of the anticipated SN birthrate from this channel have assumed that the merger process is conservative and that the primary criterion for explosion is that the merged mass exceeds the Chandrasekhar mass. Han and Webbink demonstrated that mass transfer and merger in close double WDs will in many cases be non-conservative. Pakmor et al. further suggested that the merger process should be violent in order to initiate an explosion. We have therefore investigated how the SN Ia birthrate from the double-degenerate (DD) channel is affected by these constraints. Using the binary-star population-synthesis method, we have calculated the DD SN Ia birthrate under conservative and non-conservative approximations, and including lower mass and mass-ratio limits indicated by recent smoothed-particle-hydrodynamic calculations. The predicted DD SN Ia rate is significantly reduced by all of these constraints. With dynamical mass loss alone (violent merger) the birthrate is reduced to 56% of the conservative rate. Requiring the mass ratio q > 2/3 further reduces the birthrate to 18% that of the standard assumption. An upper limit of 0.0061 SNuM, or a Galactic rate of 4.6 Multiplication-Sign 10{sup -4} yr{sup -1}, might be realistic.

  7. Investigation on Plasma Jet Flow Phenomena During DC Air Arc Motion in Bridge-Type Contacts

    NASA Astrophysics Data System (ADS)

    Zhai, Guofu; Bo, Kai; Chen, Mo; Zhou, Xue; Qiao, Xinlei

    2016-05-01

    Arc plasma jet flow in the air was investigated under a bridge-type contacts in a DC 270 V resistive circuit. We characterized the arc plasma jet flow appearance at different currents by using high-speed photography, and two polished contacts were used to search for the relationship between roughness and plasma jet flow. Then, to make the nature of arc plasma jet flow phenomena clear, a simplified model based on magnetohydrodynamic (MHD) theory was established and calculated. The simulated DC arc plasma was presented with the temperature distribution and the current density distribution. Furthermore, the calculated arc flow velocity field showed that the circular vortex was an embodiment of the arc plasma jet flow progress. The combined action of volume force and contact surface was the main reason of the arc jet flow. supported by National Natural Science Foundation of China (Nos. 51307030, 51277038)

  8. Cost analysis of new and retrofit hot-air type solar assisted heating systems

    NASA Technical Reports Server (NTRS)

    Stewart, R. D.; Hawkins, B. J.

    1978-01-01

    A detailed cost analysis/cost improvement study was performed on two Department of Energy/National Aeronautics and Space Administration operational test sites to determine actual costs and potential cost improvements of new and retrofit hot air type, solar assisted heating and hot water systems for single family sized structures. This analysis concentrated on the first cost of a system which included procurement, installation, and integration of a solar assisted heating and hot water system on a new or retrofit basis; it also provided several cost projections which can be used as inputs to payback analyses, depending upon the degree of optimism or future improvements assumed. Cost definitions were developed for five categories of cost, and preliminary estimates were developed for each. The costing methodology, approach, and results together with several candidate low cost designs are described.

  9. Effect of Fuel Composition, Engine Operating Variables, and Spark-Plug Type and Condition on Preignition-Limited Performance of an R-2800 Cylinder

    NASA Technical Reports Server (NTRS)

    Pfender, John F.

    1946-01-01

    The preignition characteristics of the R-2800 cylinder, as effected by fuel consumption, engine operating variables, and spark plug type and condition, were evaluated. The effects on preignition-limited performance of various percentages of aromatics (benzene, toluene, cumene, xylene) in a base fuel of triptane were investigated. Two paraffins (triptane and S + 6.0 ml TEL/gal) and two refinery blends (28-R and 33-R) were preignition rated. The effect of changes in the following engine operating variables on preignition limit was determined: inlet-air temperature, rear spark plug gasket temperature, engine speed, spark advance, tappet clearance, and oil consumption. Preignition limits of the R-2800 cylinder using Champion C34S and C35S and AC-LS86, LS87, and LS88 spark plugs were established and the effect of spark plug deterioration was investigated. No definite trends in preignition-limited indicated mean effective pressure were indicated for aromatics as a class when increased percentages of different aromatics were added to a base fuel of triptane. Three types of fuel (aromatics, paraffins, and refinery blends) showed a preignition range for this cylinder from 65 to 104 percent when based on the performance of S plus 6.0 ml TEL per gallon as 100 percent. The R-2800 cylinder is therefore relatively insensitive to fuel composition when compared to a CFR F-4 engine, which had a pre-ignition range from 72 to 100 percent for the same fuels. Six engine operating variables were investigated with the following results: preignition-limited indicated mean effective pressure decreased, with increases in engine speed, rear spark plug gasket temperature, inlet-air temperature, and spark advance beyond 20 F B.T.C. and was unaffected by rate of oil consumption or by tappet clearance. Spark plugs were rated over a range of preignition-limited indicated mean effective pressure from 200 to 390 pounds per square inch at a fuel-air ratio of 0.07 in the following order of increased

  10. Aerospace technology development of three types of solid state remote power controllers for 120VDC with current ratings of five, and thirty amperes, one type having current limiting

    NASA Technical Reports Server (NTRS)

    Baker, D. E.

    1975-01-01

    The first generation of remote power controllers (RPC) developed included: a 5-ampere design (Type 1), capable of limiting maximum overload current to 15 amperes for .1 sec; and 5-ampere noncurrent (Type 2) and 30-ampere noncurrent (Type 3) limiting designs, both with selectable instant trip levels for high-current overload. Each design provides overcurrent protection through an inverse I squared T trip-out function with an automatic reset option and demonstrates step-applied fault capability with a 4000-ampere surge, fast-risetime (low-inductance) power source. They also meet MIL - STD - 461A specification for electromagnetic interference. The second generation RPCs traded off specification compliance for reduction in cost and complexity for the Type 1 and 2 designs and give comparable or improved performance in most areas. The noncurrent limiting RPC proved to be a more economical and feasible method of overload protection for certain load types.

  11. Study of boron detection limit using the in-air PIGE set-up at LAMFI-USP

    NASA Astrophysics Data System (ADS)

    Moro, M. V.; Silva, T. F.; Trindade, G. F.; Added, N.; Tabacniks, M. H.

    2014-11-01

    The quantification of small amounts of boron in materials is of extreme importance in different areas of materials science. Boron is an important contaminant and also a silicon dopant in the semiconductor industry. Boron is also extensively used in nuclear power plants, either for neutron shielding or for safety control and boron is an essential nutrient for life, either vegetable or animal. The production of silicon solar cells, by refining metallurgical-grade silicon (MG-Si) requires the control and reduction of several silicon contaminants to very low concentration levels. Boron is one of the contaminants of solar-grade silicon (SG-Si) that must be controlled and quantified at sub-ppm levels. In the metallurgical purification, boron quantification is usually made by Inductive Coupled Plasma Mass Spectrometry, (ICP-MS) but the results need to be verified by an independent analytical method. In this work we present the results of the analysis of silicon samples by Particle Induced Gamma-Ray Emission (PIGE) aiming the quantification of low concentrations of boron. PIGE analysis was carried out using the in-air external beam line of the Laboratory for Materials Analysis with Ion Beans (LAMFI-USP) by the 10B ( p ,αγ(7Be nuclear reaction, and measuring the 429 keV γ-ray. The in-air PIGE measurements at LAMFI have a quantification limit of the order of 1016 at/cm2.

  12. Study of boron detection limit using the in-air PIGE set-up at LAMFI-USP

    SciTech Connect

    Moro, M. V.; Silva, T. F.; Trindade, G. F.; Added, N.; Tabacniks, M. H.

    2014-11-11

    The quantification of small amounts of boron in materials is of extreme importance in different areas of materials science. Boron is an important contaminant and also a silicon dopant in the semiconductor industry. Boron is also extensively used in nuclear power plants, either for neutron shielding or for safety control and boron is an essential nutrient for life, either vegetable or animal. The production of silicon solar cells, by refining metallurgical-grade silicon (MG-Si) requires the control and reduction of several silicon contaminants to very low concentration levels. Boron is one of the contaminants of solar-grade silicon (SG-Si) that must be controlled and quantified at sub-ppm levels. In the metallurgical purification, boron quantification is usually made by Inductive Coupled Plasma Mass Spectrometry, (ICP-MS) but the results need to be verified by an independent analytical method. In this work we present the results of the analysis of silicon samples by Particle Induced Gamma-Ray Emission (PIGE) aiming the quantification of low concentrations of boron. PIGE analysis was carried out using the in-air external beam line of the Laboratory for Materials Analysis with Ion Beams (LAMFI-USP) by the {sup 10}B(p,αγ({sup 7}Be nuclear reaction, and measuring the 429 keV γ-ray. The in-air PIGE measurements at LAMFI have a quantification limit of the order of 10{sup 16} at/cm{sup 2}.

  13. 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.

  14. Exposures to road traffic, noise, and air pollution as risk factors for type 2 diabetes: A feasibility study in Bulgaria.

    PubMed

    Dzhambov, Angel M; Dimitrova, Donka D

    2016-01-01

    Type 2 diabetes mellitus (T2DM) is a growing public health problem in Bulgaria. While individual and lifestyle determinants have been researched; till date there has been no study on environmental risks such as road traffic, noise, and air pollution. As a first step toward designing a large-scale population-based survey, we aimed at exploring the overall associations of prevalent T2DM with exposures to road traffic, noise, and air pollution. A total of 513 residents of Plovdiv city, Bulgaria were recruited. Individual data on self-reported doctor-diagnosed T2DM and confounding factors were linked to objective and self-rated exposure indicators. Logistic and log-link Poisson regressions were conducted. In the fully adjusted logistic models, T2DM was positively associated with exposures to L(den) 71-80 dB (odds ratio (OR) = 4.49, 95% confidence interval (CI): 1.38, 14.68), fine particulate matter (PM) 2.5 25.0-66.8 μg/m 3 (OR = 1.32, 95% CI: 0.28, 6.24), benzo alpha pyrene 6.0-14.02 ng/m 3 (OR = 1.76, 95% CI: 0.52, 5.98) and high road traffic (OR = 1.40, 95% CI: 0.48, 4.07). L(den) remained a significant risk factor in the: Poisson regression model. Other covariates with consistently high multivariate effects were age, gender, body mass index, family history of T2DM, subjective sleep disturbance, and especially bedroom location. We concluded that residential noise exposure might be associated with elevated risk of prevalent T2DM. The inferences made by this research and the lessons learned from its limitations could guide the designing of a longitudinal epidemiological survey in Bulgaria. PMID:27157686

  15. Exposures to road traffic, noise, and air pollution as risk factors for type 2 diabetes: A feasibility study in Bulgaria

    PubMed Central

    Dzhambov, Angel M; Dimitrova, Donka D

    2016-01-01

    Type 2 diabetes mellitus (T2DM) is a growing public health problem in Bulgaria. While individual and lifestyle determinants have been researched; till date there has been no study on environmental risks such as road traffic, noise, and air pollution. As a first step toward designing a large-scale population-based survey, we aimed at exploring the overall associations of prevalent T2DM with exposures to road traffic, noise, and air pollution. A total of 513 residents of Plovdiv city, Bulgaria were recruited. Individual data on self-reported doctor-diagnosed T2DM and confounding factors were linked to objective and self-rated exposure indicators. Logistic and log-link Poisson regressions were conducted. In the fully adjusted logistic models, T2DM was positively associated with exposures to Lden 71-80 dB (odds ratio (OR) = 4.49, 95% confidence interval (CI): 1.38, 14.68), fine particulate matter (PM)2.5 25.0-66.8 μg/m3 (OR = 1.32, 95% CI: 0.28, 6.24), benzo alpha pyrene 6.0-14.02 ng/m3 (OR = 1.76, 95% CI: 0.52, 5.98) and high road traffic (OR = 1.40, 95% CI: 0.48, 4.07). Lden remained a significant risk factor in the: Poisson regression model. Other covariates with consistently high multivariate effects were age, gender, body mass index, family history of T2DM, subjective sleep disturbance, and especially bedroom location. We concluded that residential noise exposure might be associated with elevated risk of prevalent T2DM. The inferences made by this research and the lessons learned from its limitations could guide the designing of a longitudinal epidemiological survey in Bulgaria. PMID:27157686

  16. Small field in-air output factors: The role of miniphantom design and dosimeter type

    SciTech Connect

    Warrener, Kirbie; Hug, Benjamin; Ebert, Martin A.; Liu, Paul; McKenzie, David R.; Ralston, Anna; Suchowerska, Natalka

    2014-02-15

    Purpose: The commissioning of treatment planning systems and beam modeling requires measured input parameters. The measurement of relative output in-air, S{sub c} is particularly difficult for small fields. The purpose of this study was to investigate the influence of miniphantom design and detector selection on measured S{sub c} values for small fields and to validate the measurements against Monte Carlo simulations. Methods: Measurements were performed using brass caps (with sidewalls) or tops (no sidewalls) of varying heights and widths. The performance of two unshielded diodes (60012 and SFD), EBT2 radiochromic film, and a fiber optic dosimeter (FOD) were compared for fields defined by MLCs (5–100 mm) and SRS cones (4–30 mm) on a Varian Novalis linear accelerator. Monte Carlo simulations were performed to theoretically predict S{sub c} as measured by the FOD. Results: For all detectors, S{sub c} agreed to within 1% for fields larger than 10 mm and to within 2.3% for smaller fields. Monte Carlo simulation matched the FOD measurements for all size of cone defined fields to within 0.5%. Conclusions: Miniphantom design is the most important variable for reproducible and accurate measurements of the in-air output ratio, S{sub c}, in small photon fields (less than 30 mm). Sidewalls are not required for fields ≤ 30 mm and tops are therefore preferred over the larger caps. Unlike output measurements in water, S{sub cp,} the selection of detector type for S{sub c} is not critical, provided the active dosimeter volume is small relative to the field size.

  17. Model-based flow rate control for an orfice-type low-volume air sampler

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The standard method of measuring air suspended particulate matter concentration per volume of air consists of continuously drawing a defined volume of air across a filter over an extended period of time, then measuring the mass of the filtered particles and dividing it by the total volume sampled ov...

  18. Air pollution and diabetes association: Modification by type 2 diabetes genetic risk score.

    PubMed

    Eze, Ikenna C; Imboden, Medea; Kumar, Ashish; von Eckardstein, Arnold; Stolz, Daiana; Gerbase, Margaret W; Künzli, Nino; Pons, Marco; Kronenberg, Florian; Schindler, Christian; Probst-Hensch, Nicole

    2016-09-01

    Exposure to ambient air pollution (AP) exposure has been linked to type 2 diabetes (T2D) risk. Evidence on the impact of T2D genetic variants on AP susceptibility is lacking. Compared to single variants, joint genetic variants contribute substantially to disease risk. We investigated the modification of AP and diabetes association by a genetic risk score (GRS) covering 63 T2D genes in 1524 first follow-up participants of the Swiss cohort study on air pollution and lung and heart diseases in adults. Genome-wide data and covariates were available from a nested asthma case-control study design. AP was estimated as 10-year mean residential particulate matter <10μm (PM10). We computed count-GRS and weighted-GRS, and applied PM10 interaction terms in mixed logistic regressions, on odds of diabetes. Analyses were stratified by pathways of diabetes pathology and by asthma status. Diabetes prevalence was 4.6% and mean exposure to PM10 was 22μg/m(3). Odds of diabetes increased by 8% (95% confidence interval: 2, 14%) per T2D risk allele and by 35% (-8, 97%) per 10μg/m(3) exposure to PM10. We observed a positive interaction between PM10 and count-GRS on diabetes [ORinteraction=1.10 (1.01, 1.20)], associations being strongest among participants at the highest quartile of count-GRS [OR: 1.97 (1.00, 3.87)]. Stronger interactions were observed with variants of the GRS involved in insulin resistance [(ORinteraction=1.22 (1.00, 1.50)] than with variants related to beta-cell function. Interactions with count-GRS were stronger among asthma cases. We observed similar results with weighted-GRS. Five single variants near GRB14, UBE2E2, PTPRD, VPS26A and KCNQ1 showed nominally significant interactions with PM10 (P<0.05). Our results suggest that genetic risk for T2D may modify susceptibility to air pollution through alterations in insulin sensitivity. These results need confirmation in diabetes cohort consortia. PMID:27281273

  19. Identifying nitrogen limitations to organic sediments accumulation in various vegetation types of arctic tundra (Hornsund, Svalbard)

    NASA Astrophysics Data System (ADS)

    Skrzypek, G.; Wojtuń, B.; Hua, Q.; Richter, D.; Jakubas, D.; Wojczulanis-Jakubas, K.; Samecka-Cymerman, A.

    2015-12-01

    Arctic and subarctic regions play important roles in the global carbon balance. However, nitrogen (N) deficiency is a major constraint for organic carbon sequestration in the High Arctic. Hence, the identification of the relative contributions from different N-sources is critical for understanding the constraints that limit tundra growth. The stable nitrogen composition of the three main N-sources and numerous plants were analyzed in ten tundra types in the Fuglebekken catchment (Hornsund Fjord, Svalbard, 77°N 15°E). The percentage of the total tundra N-pool provided by seabirds' feces (colonially breeding, planktivorous Alle alle), ranged from 0-21% in Patterned-ground tundra to 100% in Ornithocoprophilous tundra. The total N-pool utilized by tundra plants in the studied catchment was built in 36% by birds, 38% by atmospheric deposition, and 26% by N2-fixation. The results clearly show that N-pool in the tundra is significantly supplemented by nesting seabirds. Thus, if they experienced substantial negative environmental pressure associated with climate change, it would adversely influence the tundra N-budget [1]. The growth rates and the sediment thickness (<15 cm) in different tundra types varied considerably but the tundra age was similar, <450 cal BP. The only exception was Ornithocoprophilous tundra with very diverse ages ranging from 235 to 2300 cal BP and thickness up to 110cm. The growth rates for this tundra (62 cm core, 18 AMS 14C dates) were high (1.5-3.0 mm/yr) between 1568 and 1804 AD and then substantially declined for the period between 1804 and 1929 AD (0.2 mm/yr). These findings deliver an additional argument, that the organic matter accumulation is driven not only directly by climatic conditions but also by birds' contribution to the tundra N-pool. [1] Skrzypek G, Wojtuń B, Richter D, Jakubas D, Wojczulanis-Jakubas K, Samecka-Cymerman A, 2015. Diversification of nitrogen sources in various tundra vegetation types in the high Arctic. PLoS ONE

  20. Response of duffing-type harvesters to band-limited noise

    NASA Astrophysics Data System (ADS)

    Masana, Ravindra; Daqaq, Mohammed F.

    2013-12-01

    This paper aims to experimentally investigate the influence of stiffness-type nonlinearities on the transduction of vibratory energy harvesters (VEHs) under band-limited noise. For the purpose of the study, an energy harvester consisting of a clamped-clamped piezoelectric beam bi-morph is considered. The shape of the harvester's potential function is altered by applying a static compressive axial load at one end of the beam. The axial load permits the harvester to operate with different potential energy characteristics, namely, the mono-stable (pre-buckling) and bi-stable (post-buckling) configurations. The performance of the harvester in both the configurations is investigated and compared by tuning the harvester's oscillation frequencies around the static equilibria such that they have equal values in both scenarios. The harvester is then subjected to random base excitations of different levels, bandwidths, and center frequencies. The variance of the output voltage is measured across an arbitrary, purely resistive load and used for the purpose of performance comparison. Critical conclusions pertinent to the influence of the nonlinearity and relative performance in both configurations are presented and discussed.

  1. Chromium supplements for glycemic control in type 2 diabetes: limited evidence of effectiveness.

    PubMed

    Costello, Rebecca B; Dwyer, Johanna T; Bailey, Regan L

    2016-07-01

    Some adults with type 2 diabetes mellitus (T2DM) believe that chromium-containing supplements will help control their disease, but the evidence is mixed. This narrative review examines the efficacy of chromium supplements for improving glycemic control as measured by decreases in fasting plasma glucose (FPG) or hemoglobin A1c (HbA1c). Using systematic search criteria, 20 randomized controlled trials of chromium supplementation in T2DM patients were identified. Clinically meaningful treatment goals were defined as an FPG of ≤7.2 mmol/dL, a decline in HbA1c to ≤7%, or a decrease of ≥0.5% in HbA1c. In only a few randomized controlled trials did FPG (5 of 20), HbA1c (3 of 14), or both (1 of 14) reach the treatment goals with chromium supplementation. HbA1c declined by ≥0.5% in 5 of 14 studies. On the basis of the low strength of existing evidence, chromium supplements have limited effectiveness, and there is little rationale to recommend their use for glycemic control in patients with existing T2DM. Future meta-analyses should include only high-quality studies with similar forms of chromium and comparable inclusion/exclusion criteria to provide scientifically sound recommendations for clinicians. PMID:27261273

  2. Ambient air quality and emission characteristics in and around a non-recovery type coke oven using high sulphur coal.

    PubMed

    Saikia, Jyotilima; Saikia, Prasenjit; Boruah, Ratan; Saikia, Binoy K

    2015-10-15

    The objective of this study is to determine the concentrations of gaseous species and aerosols in and around a non-recovery type coke making oven using high sulphur coals. In this paper, physico-chemical properties of the feed coal sample are reported along with the collection and measurement of the emitted gases (SO2, NO2, and NH3) and aerosol particles (PM2.5, PM10) during the coal carbonization in the oven. The coals used are from northeast India and they are high sulphur in nature. The concentrations of the gases e.g., SO2, NO2 and NH3 emitted are observed to be within the limit of National Ambient Air Quality Standard for 24h. The mean PM10 and PM2.5 concentrations are found to be 125.4 μg/m(3) and 48.6 μg/m(3) respectively, as measured during three days of coke oven operations. About 99% of the SO2 in flue gases is captured by using an alkali treatment during the coke oven operation. A Principal Component Analysis (PCA) after Centred Log Ratio (clr) transformation is also performed to know the positive and negative correlation among the coal properties and the emission parameters. PMID:26047865

  3. New mass limit for white dwarfs: super-Chandrasekhar type ia supernova as a new standard candle.

    PubMed

    Das, Upasana; Mukhopadhyay, Banibrata

    2013-02-15

    Type Ia supernovae, sparked off by exploding white dwarfs of mass close to the Chandrasekhar limit, play the key role in understanding the expansion rate of the Universe. However, recent observations of several peculiar type Ia supernovae argue for its progenitor mass to be significantly super-Chandrasekhar. We show that strongly magnetized white dwarfs not only can violate the Chandrasekhar mass limit significantly, but exhibit a different mass limit. We establish from a foundational level that the generic mass limit of white dwarfs is 2.58 solar mass. This explains the origin of overluminous peculiar type Ia supernovae. Our finding further argues for a possible second standard candle, which has many far reaching implications, including a possible reconsideration of the expansion history of the Universe. PMID:25166364

  4. Limitations and barriers for adopting sustainable management practices in different farm types across Europe

    NASA Astrophysics Data System (ADS)

    Guzmán, Gema; Portero, Ángela; Vanwalleghem, Tom; Pedrera, Ana; Jesús Gaitán, Antonio; Ten Berge, Hein

    2014-05-01

    Although apparently the conservation of natural resources such as water and soil does not represent important concerns for our society, the evolution of the world population and the degradation of these resources pose a challenge to improving agricultural food production capacity and conserving, and in some cases restoring, the environmental quality. Unfortunately, the history contains numerous examples of abandonment of these resources (McNeill 1992, Montgomery 2007). Although most of the agronomic conservation practices have been known for millennia, their implementation has often been hindered by non-agricultural motives (Davis et al. 2012). The European project CATCH-C (ten Berge 2011) started last year with the aim of evaluating sustainable soil management practices and exploring the difficulties for their adoption, both at farm and institutional level, to overcome them in the near future. As a first step with that purpose, a selection of best management practices (BMPs) based on interviews with advisors and scientific knowledge were proposed for each of the considered farm typologies: arable crops, permanent crops and pasture. These farm types are representative of the Mediterranean area in terms of agroecological properties, extension, economical importance and soil degradation problems. Semi-structured interviews were carried out by addressing different profiles of farmers to identify in a qualitative way the main limitations for adopting these BMPs on their farms. Different questionnaires were prepared based on the farmers' responses and launched at a larger scale, with the aim of achieving approximately 100 responses per each farm typology. Finally, responses from the questionnaires will be analyzed to explore the causes that hinder or impede the adoption of BMPs in different farm typologies. References: Davis A.S. et al. 2012. Plos ONE 7(10): e4719. doi:10.1371/journalpone.0047149. McNeill, J.R. 1992. The mountains of the Mediterranean world. Cambridge

  5. Thermally stable J-type phthalocyanine dimers as new non-linear absorbers for low-threshold optical limiters.

    PubMed

    Tolbin, Alexander Yu; Savelyev, Mikhail S; Gerasimenko, Alexander Yu; Tomilova, Larisa G; Zefirov, Nikolay S

    2016-06-21

    The possibility of developing new advanced optical limiters of laser radiation at 532 nm with low limiting thresholds has been demonstrated on thermally stable phthalocyanine J-type dimeric complexes of Mg, Zn, Cu, Ni, and Co. A new "threshold" model based on radiative transfer phenomena in nonlinear optical media was suggested for the exact definition of nonlinear absorption coefficient β and optical limiting threshold Ic. This model allows the determination of the optical characteristics of the limiter in the same active material with layers of different thicknesses, as well as the use of different parameters of laser radiation, such as cross-sectional spatial profiles of the laser beam and shapes of the laser pulse over time. The maximum value of the nonlinear absorption coefficient (β = 360 cm GW(-1)) and the lowest limiting threshold (Ic = 0.03 J cm(-2)) were estimated for a J-type zinc phthalocyanine dimer. PMID:27241278

  6. Short-term 222Rn activity concentration changes in underground spaces with limited air exchange with the atmosphere

    NASA Astrophysics Data System (ADS)

    Fijałkowska-Lichwa, L.; Przylibski, T. A.

    2011-04-01

    The authors investigated short-time changes in 222Rn activity concentration occurring yearly in two underground tourist facilities with limited air exchange with the atmosphere. One of them is Niedźwiedzia (Bear) Cave in Kletno, Poland - a natural space equipped with locks ensuring isolation from the atmosphere. The other site is Fluorite Adit in Kletno, a section of a disused uranium mine. This adit is equipped with a mechanical ventilation system, operated periodically outside the opening times (at night). Both sites are situated within the same metamorphic rock complex, at similar altitudes, about 2 km apart. The measurements conducted revealed spring and autumn occurrence of convective air movements. In Bear Cave, this process causes a reduction in 222Rn activity concentration in the daytime, i.e. when tourists, guides and other staff are present in the cave. From the point of view of radiation protection, this is the best situation. For the rest of the year, daily concentrations of 222Rn activity in the cave are very stable. In Fluorite Adit, on the other hand, significant variations in daily 222Rn activity concentrations are recorded almost all year round. These changes are determined by the periods of activity and inactivity of mechanical ventilation. Unfortunately this is inactive in the daytime, which results in the highest values of 222Rn activity concentration at the times when tourists and staff are present in the adit. Slightly lower concentrations of radon in Fluorite Adit are recorded in the winter season, when convective air movements carry a substantial amount of radon out into the atmosphere. The incorrect usage of mechanical ventilation in Fluorite Adit results in the most unfavourable conditions in terms of radiation protection. The staff working in that facility are exposed practically throughout the year to the highest 222Rn activity concentrations, both at work (in the adit) and at home (outside their working hours). Therefore, not very well

  7. The assessment of future extremes of air temperature to design EPR type power plants

    NASA Astrophysics Data System (ADS)

    Parey, S.; Hoang, T. T. H.; Dacunha-Castelle, D.

    2010-09-01

    EDF projects the construction of new EPR type nuclear power plants in Europe. These installations are likely to run until the second half of the century, and thus, it is necessary to think their dimensioning in taking current knowledge of climate change impact into account. This paper will present the study dedicated to the estimation of future extremes of air temperature by using the statistical extreme value theory. The adopted methodology consists firstly in comparing current climate temperature extremes between local observations and models at the nearest grid point. Then, if the extremes of both series are comparable, future extremes are derived from the modelled series for a future period. In parallel, the link between the evolution of the mean, variance and extremes is studied in the observation series. If a strong link is identified, future extremes are derived from the stationary extremes of the centred and normalised series and the changes in mean and variance given by climate models for the desired future period. The approach will be illustrated with an example of such an evaluation for an EPR project in the United Kingdom.

  8. Limited Effects of Type I Interferons on Kyasanur Forest Disease Virus in Cell Culture

    PubMed Central

    Cook, Bradley W. M.; Ranadheera, Charlene; Nikiforuk, Aidan M.; Cutts, Todd A.; Kobasa, Darwyn; Court, Deborah A.; Theriault, Steven S.

    2016-01-01

    Background The tick-borne flavivirus, Kyasanur Forest disease virus (KFDV) causes seasonal infections and periodic outbreaks in south-west India. The current vaccine offers poor protection with reported issues of coverage and immunogenicity. Since there are no approved prophylactic therapeutics for KFDV, type I IFN-α/β subtypes were assessed for antiviral potency against KFDV in cell culture. Methodology/Principal Findings The continued passage of KFDV-infected cells with re-administered IFN-α2a treatment did not eliminate KFDV and had little effect on infectious particle production whereas the IFN-sensitive, green fluorescent protein-expressing vesicular stomatitis virus (VSV-GFP) infection was controlled. Further evaluation of the other IFN-α/β subtypes versus KFDV infection indicated that single treatments of either IFN-αWA and IFN-αΚ appeared to be more effective than IFN-α2a at reducing KFDV titres. Concentration-dependent analysis of these IFN-α/β subtypes revealed that regardless of subtype, low concentrations of IFN were able to limit cytopathic effects (CPE), while significantly higher concentrations were needed for inhibition of virion release. Furthermore, expression of the KFDV NS5 in cell culture before IFN addition enabled VSV-GFP to overcome the effects of IFN-α/β signalling, producing a robust infection. Conclusions/Significance Treatment of cell culture with IFN does not appear to be suitable for KFDV eradication and the assay used for such studies should be carefully considered. Further, it appears that the NS5 protein is sufficient to permit KFDV to bypass the antiviral properties of IFN. We suggest that other prophylactic therapeutics should be evaluated in place of IFN for treatment of individuals with KFDV disease. PMID:27479197

  9. 42 CFR 84.156 - Airflow resistance test; Type C supplied-air respirator, demand class; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Airflow resistance test; Type C supplied-air respirator, demand class; minimum requirements. 84.156 Section 84.156 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE...

  10. 42 CFR 84.157 - Airflow resistance test; Type C supplied-air respirator, pressure-demand class; minimum...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Airflow resistance test; Type C supplied-air respirator, pressure-demand class; minimum requirements. 84.157 Section 84.157 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY...

  11. An objective classification system of air mass types for Szeged, Hungary, with special attention to plant pollen levels.

    PubMed

    Makra, László; Juhász, Miklós; Mika, János; Bartzokas, Aristides; Béczi, Rita; Sümeghy, Zoltán

    2006-07-01

    This paper discusses the characteristic air mass types over the Carpathian Basin in relation to plant pollen levels over annual pollination periods. Based on the European Centre for Medium-Range Weather Forecasts dataset, daily sea-level pressure fields analysed at 00 UTC were prepared for each air mass type (cluster) in order to relate sea-level pressure patterns to pollen levels in Szeged, Hungary. The database comprises daily values of 12 meteorological parameters and daily pollen concentrations of 24 species for their pollination periods from 1997 to 2001. Characteristic air mass types were objectively defined via factor analysis and cluster analysis. According to the results, nine air mass types (clusters) were detected for pollination periods of the year corresponding to pollen levels that appear with higher concentration when irradiance is moderate while wind speed is moderate or high. This is the case when an anticyclone prevails in the region west of the Carpathian Basin and when Hungary is under the influence of zonal currents (wind speed is high). The sea level pressure systems associated with low pollen concentrations are mostly similar to those connected to higher pollen concentrations, and arise when wind speed is low or moderate. Low pollen levels occur when an anticyclone prevails in the region west of the Carpathian Basin, as well as when an anticyclone covers the region with Hungary at its centre. Hence, anticyclonic or anticyclonic ridge weather situations seem to be relevant in classifying pollen levels. PMID:16575583

  12. 42 CFR 84.149 - Type C supplied-air respirator, demand and pressure demand 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, demand and pressure demand class; minimum requirements. 84.149 Section 84.149 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES...

  13. Diagnosis and management of type II myocardial infarction: increased demand for a limited supply of evidence.

    PubMed

    Smilowitz, Nathaniel R; Naoulou, Becky; Sedlis, Steven P

    2015-01-01

    Type 2 myocardial infarction (type 2 MI) is defined as myocardial necrosis that results from an imbalance of myocardial oxygen supply and demand. Although type 2 MI is highly prevalent and strongly associated with mortality, the pathophysiology remains poorly understood. Discrepancies in definitions, frequency of screening, diagnostic approaches, and methods of adjudication lead to confusion and misclassification. To date, there is no consensus on the diagnostic criteria for type 2 MI. No guidelines exist for the optimal management of this condition, and further investigation is urgently needed. This review explores the existing evidence on the pathophysiology, diagnosis, prognosis, and management of type 2 MI. PMID:25620276

  14. Clark Lake microbursts - On a lower limit to type III burst brightness temperatures

    NASA Technical Reports Server (NTRS)

    White, S. M.; Kundu, M. R.; Szabo, A.

    1987-01-01

    Further observations of solar microbursts by the Clark Lake radioheliograph are reported. The microbursts have properties consistent with weak type III bursts, with the implication that type III's can have brightness temperatures as low as 1 million K. The importance of this result is explored. A single model to explain the stronger type III bursts and the weaker microbursts is sought. It is shown that none of the models for stabilizing the strongest type III electron streams can explain the observed microbursts: these models have threshold levels of Langmuir waves which imply emission (due to spontaneous scattering off ions) with brightness temperatures in excess of those observed. It appears that either some vital physics is still missing from models for type III bursts, or that microbursts should have properties significantly different from those of type III bursts. In the latter case further observations should allow important tests of type III models.

  15. Vent means for closed air system impact-type seismic source

    SciTech Connect

    Airhart, T.P.

    1987-10-27

    This patent describes an apparatus for impacting a target comprising: (a) a hollow upstanding cylindrical housing having a closed upper end and open lower end and provided with a longitudinal bore; (b) a pressurized air supply vessel communicating with the bore through the first air passage; (c) piston means slidably interfitted with the bore for movement therein; (d) valve means for regulating air flow through the second air passage; (e) means for supporting the piston means in an upper most position in which piston means projects above and blocks the first air passage so as to isolate the air supply vessel from the bore and so as to engage the valve means in a manner to maintain the second air passage in an unblocked condition; (f) means for releasing the piston means such that the resultant gravity-induced movement is accompanied in sequence by disengagement with the valve means and unblocking of the first air passage; (g) means for returning the piston means to such upper most position.

  16. Novel and recurrent mutations in the AIRE gene of autoimmune polyendocrinopathy syndrome type 1 (APS1) patients.

    PubMed

    Faiyaz-Ul-Haque, M; Bin-Abbas, B; Al-Abdullatif, A; Abdullah Abalkhail, H; Toulimat, M; Al-Gazlan, S; Almutawa, A M; Al-Sagheir, A; Peltekova, I; Al-Dayel, F; Zaidi, S H E

    2009-11-01

    Autoimmune polyendocrinopathy syndrome type 1 (APS1) is characterized by the presence of at least two out of three clinical features, which include Addison's disease, hypoparathyroidism, and chronic mucocutaneous candidiasis. This disorder is caused by mutations in the AIRE (autoimmune regulator) gene. While several AIRE mutations have been described in APS1 patients of various ethnic origins, the genetic cause of APS1 in Arab patients requires further investigation. This study describes seven Arab families, in which 18 patients had APS1. In addition to the cardinal features of APS1, some patients exhibited alopecia, diabetes mellitus, nephrocalcinosis and other phenotypes associated with APS1. DNA sequencing of the AIRE gene of patients from this study identified four novel and one recurrent mutation. These mutations likely result in loss of AIRE function in the patients. In addition, it was noted that the non-pathogenic c.834C> G mutation (rs1800520, encoding for p.Ser278Arg) occurs with high incidence in the AIRE gene of Arab individuals. Furthermore, this investigation demonstrates inflammation of the hair follicles in APS1 patients with alopecia universalis. We conclude that Arab APS1 patients carry novel and recurrent mutations in the AIRE gene. PMID:19758376

  17. Actual Performance Prediction of Split-type Room Air Conditioner which Considered Unsteady Operation Concerning Heat Island Problem

    NASA Astrophysics Data System (ADS)

    Shinomiya, Naruaki; Nishimura, Nobuya; Iyota, Hiroyuki; Nomura, Tomohiro

    Split type air conditioners are operated actually in the situation unlike the condition that was described in a product catalog. On the other hand, exhaust heat from air conditioner is considered as one of the causes of heat island problem in urban area, and the air conditioner performance and heat load affect exhaust heat amount. In this study, air conditioner performances in both standard summer day and severe hot day were examined by dynamic simulation which considered outdoor weather changes. As a result, actual performances of the air conditioner were demonstrated as a function of outdoor temperature, heat load and indoor temperature. The higher the outdoor temperature and heat load rise, the smaller influences of indoor temperature against COP became. In standard summer day, relative performance exceeded by 15 to 45% than that of JIS operating condition. Also, COP in severe hot day decreased about 6% at the peak time than that of standard day. As a result, the air conditioner exhaust heat during one day which was predicted by the proposed simulation model became about 16% smaller than the conventional prediction model.

  18. Air-stable n-type organic thin-film transistor array and high gain complementary inverter on flexible substrate

    NASA Astrophysics Data System (ADS)

    Fujisaki, Yoshihide; Nakajima, Yoshiki; Kumaki, Daisuke; Yamamoto, Toshihiro; Tokito, Shizuo; Kono, Takahiro; Nishida, Jun-ichi; Yamashita, Yoshiro

    2010-09-01

    Air-stable n-type organic thin-film transistor (TFT) arrays and a complementary inverter circuit were fabricated on a flexible substrate. A benzobis(thiadiazole) (BBT) derivative-based TFT showed excellent air- stability and performances such as an electron mobility of over 0.1 cm2/V s, a large ON/OFF ratio over 108 when combined with a cross-linkable olefin-type polymer gate dielectric. In addition, an organic complementary inverter that combined the BBT derivative and a pentacene TFT demonstrated a sharp switching behavior and a high gain of over 150. We attribute these excellent characteristics to a combination of the low-lying lowest unoccupied molecular orbital level of n-type semiconductor material and the low interface trap of the gate dielectric.

  19. Synoptic weather types and aeroallergens modify the effect of air pollution on hospitalisations for asthma hospitalisations in Canadian cities.

    PubMed

    Hebbern, Christopher; Cakmak, Sabit

    2015-09-01

    Pollution levels and the effect of air pollution on human health can be modified by synoptic weather type and aeroallergens. We investigated the effect modification of aeroallergens on the association between CO, O3, NO2, SO2, PM10, PM2.5 and asthma hospitalisation rates in seven synoptic weather types. We developed single air pollutant models, adjusted for the effect of aeroallergens and stratified by synoptic weather type, and pooled relative risk estimates for asthma hospitalisation in ten Canadian cities. Aeroallergens significantly modified the relative risk in 19 pollutant-weather type combinations, reducing the size and variance for each single pollutant model. However, aeroallergens did not significantly modify relative risk for any pollutant in the DT or MT weather types, or for PM10 in any weather type. Thus, there is a modifying effect of aeroallergens on the association between CO, O3, NO2, SO2, PM2.5 and asthma hospitalisations that differs under specific synoptic weather types. PMID:25898232

  20. Mediatorless glucose biosensor and direct electron transfer type glucose/air biofuel cell enabled with carbon nanodots.

    PubMed

    Zhao, Mei; Gao, Yue; Sun, Junyong; Gao, Feng

    2015-03-01

    Utilization of carbon nanodots (CNDs), newcomers to the world of carbonaceous nanomaterials, in the electrochemistry realm has rarely been reported so far. In this study, CNDs were used as immobilization supports and electron carriers to promote direct electron transfer (DET) reactions of glucose oxidase (GOx) and bilirubin oxidase (BOD). At the CNDs electrode entrapped with GOx, a high rate constant (k(s)) of 6.28 ± 0.05 s(-1) for fast DET and an apparent Michaelis-Menten constant (K(M)(app)) as low as 0.85 ± 0.03 mM for affinity to glucose were found. By taking advantage of its excellent direct bioelectrocatalytic performances to glucose oxidation, a DET-based biosensor for glucose detection ranging from 0 to 0.64 mM with a high sensitivity of 6.1 μA mM(-1) and a limit of detection (LOD) of 1.07 ± 0.03 μM (S/N = 3) was proposed. Additionally, the promoted DET of BOD immobilized on CNDs was also observed and effectively catalyzed the reduction of oxygen to water at the onset potential of +0.51 V (vs Ag/AgCl). On the basis of the facilitated DET of these two enzymes at CNDs electrodes, a mediator-free DET-type glucose/air enzymatic biofuel cell (BFC), in which CNDs electrodes entrapped with GOx and BOD were employed for oxidizing glucose at the bioanode and reducing oxygen at the biocathode, respectively, was successfully fabricated. The constructed BFC displayed an open-circuit voltage (OCV) as high as 0.93 V and a maximum power density of 40.8 μW cm(-2) at 0.41 V. These important features of CNDs have implied to be promising materials for immobilizing enzymes and efficient platforms for elaborating bioelectrochemical devices such as biosensors and BFCs. PMID:25666266

  1. Exact solution of the Dirac equation with the Mie-type potential under the pseudospin and spin symmetry limit

    SciTech Connect

    Aydogdu, Oktay Sever, Ramazan

    2010-02-15

    We investigate the exact solution of the Dirac equation for the Mie-type potentials under the conditions of pseudospin and spin symmetry limits. The bound state energy equations and the corresponding two-component spinor wave functions of the Dirac particles for the Mie-type potentials with pseudospin and spin symmetry are obtained. We use the asymptotic iteration method in the calculations. Closed forms of the energy eigenvalues are obtained for any spin-orbit coupling term {kappa}. We also investigate the energy eigenvalues of the Dirac particles for the well-known Kratzer-Fues and modified Kratzer potentials which are Mie-type potentials.

  2. MEASUREMENT OF VOLATILE ORGANIC COMPOUNDS DURING START-UP OF BIOREMEDIATION OF FRENCH LIMITED SUPERFUND SITE IN CROSBY TEXAS USING WIND DEPENDENT WHOLE-AIR SAMPLING

    EPA Science Inventory

    Whole-air sampling was performed before and after the start-up of the bioremediation of an industrial (primarily petrochemical) waste lagoon in Crosby Texas, near Houston. our "Sector Samplers" were deployed at the four corners of the French Limited Superfund Site. hese samplers ...

  3. Biochemical acclimation, stomatal limitation and precipitation patterns underlie decreases in photosynthetic stimulation of Soybean (Glycine max) at elevated [CO2] and temperatures under fully open air field conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The net effect of elevated [CO2] and temperature on photosynthetic acclimation and plant productivity is poorly resolved. We assessed the effects of canopy warming and fully open air [CO2] enrichment on 1) the acclimation of two biochemical parameters that frequently limit photosynthesis (A), the ma...

  4. How Small Can We Go: Exploring the Limitations and Scaling laws of Air-Microfluidic Particulate Matter Sensors

    EPA Science Inventory

    Air-microfluidics is a field that has the potential to dramatically reduce the size, cost, and power requirements of future air quality sensors. Microfabrication provides a suite of relatively new tools for the development of micro electro mechanical systems (MEMS) that can be ap...

  5. 45 CFR 286.55 - What types of costs are subject to the administrative cost limit on Tribal Family Assistance...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 2 2011-10-01 2011-10-01 false What types of costs are subject to the administrative cost limit on Tribal Family Assistance Grant funds? 286.55 Section 286.55 Public Welfare Regulations Relating to Public Welfare OFFICE OF FAMILY ASSISTANCE (ASSISTANCE PROGRAMS), ADMINISTRATION FOR CHILDREN AND FAMILIES, DEPARTMENT OF HEALTH...

  6. Flight investigation of piloting techniques and crosswind limitations using a research type crosswind landing gear

    NASA Technical Reports Server (NTRS)

    Fisher, B. D.; Deal, P. L.; Champine, R. A.; Patton, J. M., Jr.

    1979-01-01

    A research-type crosswind landing gear was tested in a flight program which used a light STOL transport in strong crosswind conditions. The research-type crosswind landing gear used enabled the airplane to land to crosswinds up to a magnitude of 25 to 30 knots. Three modes of landing-gear operation were investigated: preset, automatic, and castor (passive self-alignment). Actual test data and histograms are given for the 195 'visual flight rules' crosswind landings made.

  7. OBSERVATIONAL LIMITS ON TYPE 1 ACTIVE GALACTIC NUCLEUS ACCRETION RATE IN COSMOS

    SciTech Connect

    Trump, Jonathan R.; Impey, Chris D.; Gabor, Jared; Kelly, Brandon C.; Elvis, Martin; Hao Heng; Huchra, John P.; Merloni, Andrea; Bongiorno, Angela; Brusa, Marcella; Cappelluti, Nico; McCarthy, Patrick J.; Koekemoer, Anton; Nagao, Tohru; Salvato, Mara; Scoville, Nick Z.

    2009-07-20

    We present black hole masses and accretion rates for 182 Type 1 active galactic nuclei (AGNs) in COSMOS. We estimate masses using the scaling relations for the broad H {beta}, Mg II, and C IV emission lines in the redshift ranges 0.16 < z < 0.88, 1 < z < 2.4, and 2.7 < z < 4.9. We estimate the accretion rate using an Eddington ratio L{sub I}/L{sub Edd} estimated from optical and X-ray data. We find that very few Type 1 AGNs accrete below L{sub I} /L{sub Edd} {approx} 0.01, despite simulations of synthetic spectra which show that the survey is sensitive to such Type 1 AGNs. At lower accretion rates the broad-line region may become obscured, diluted, or nonexistent. We find evidence that Type 1 AGNs at higher accretion rates have higher optical luminosities, as more of their emission comes from the cool (optical) accretion disk with respect to shorter wavelengths. We measure a larger range in accretion rate than previous works, suggesting that COSMOS is more efficient at finding low accretion rate Type 1 AGNs. However, the measured range in accretion rate is still comparable to the intrinsic scatter from the scaling relations, suggesting that Type 1 AGNs accrete at a narrow range of Eddington ratio, with L{sub I} /L{sub Edd} {approx} 0.1.

  8. 78 FR 37821 - Tribal Self-Governance Program, Negotiation Cooperative Agreement, Announcement Type: New-Limited...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-24

    ... HUMAN SERVICES Indian Health Service Tribal Self-Governance Program, Negotiation Cooperative Agreement... (IHS) Office of Tribal Self-Governance (OTSG) is accepting limited competition Negotiation Cooperative.... Purpose The purpose of this Negotiation Cooperative Agreement is to provide Tribes with resources to...

  9. The same type of visual working memory limitations in humans and monkeys.

    PubMed

    Devkar, Deepna T; Wright, Anthony A; Ma, Wei Ji

    2015-01-01

    Rhesus monkeys are widely used as an animal model for human memory, including visual working memory (VWM). It is, however, unknown whether the same principles govern VWM in humans and rhesus monkeys. Here, we tested both species in nearly identical change-localization paradigms and formally compared the same set of models of VWM limitations. These models include the classic item-limit model and recent noise-based (resource) models, as well as hybrid models that combine a noise-based representation with an item limit. By varying the magnitude of the change in addition to the typical set size manipulation, we were able to show large differences in goodness of fit among the five models tested. In spite of quantitative performance differences between the species, we find that the variable-precision model--a noise-based model--best describes the behavior of both species. Adding an item limit to this model does not help to account for the data. Our results suggest evolutionary continuity of VWM across primates and help establish the rhesus monkey as a model system for studying the neural substrates of multiple-item VWM. PMID:26720277

  10. Limited and localized outbreak of newly emergent type 2 vaccine-derived poliovirus in Sichuan, China.

    PubMed

    Yan, Dongmei; Zhang, Yong; Zhu, Shuangli; Chen, Na; Li, Xiaolei; Wang, Dongyan; Ma, Xiaozhen; Zhu, Hui; Tong, Wenbin; Xu, Wenbo

    2014-07-01

    From August 2011 to February 2012, an outbreak caused by type 2 circulating vaccine-derived poliovirus (cVDPV) occurred in Aba County, Sichuan, China. During the outbreak, four type 2 VDPVs (≥0.6% nucleotide divergence in the VP1 region relative to the Sabin 2 strain) were isolated from 3 patients with acute flaccid paralysis (AFP) and one close contact. In addition, a type 2 pre-VDPV (0.3% to 0.5% divergence from Sabin 2) that was genetically related to these type 2 VDPVs was isolated from another AFP patient. These 4 patients were all unimmunized children 0.7 to 1.1 years old. Nucleotide sequencing revealed that the 4 VDPV isolates differed from Sabin 2 by 0.7% to 1.2% in nucleotides in the VP1 region and shared 5 nucleotide substitutions with the pre-VDPV. All 5 isolates were closely related, and all were S2/S3/S2/S3 recombinants sharing common recombination crossover sites. Although the two major determinants of attenuation and temperature sensitivity phenotype of Sabin 2 (A481 in the 5' untranslated region and Ile143 in the VP1 protein) had reverted in all 5 isolates, one VDPV (strain CHN16017) still retained the temperature sensitivity phenotype. Phylogenetic analysis of the third coding position of the complete P1 coding region suggested that the cVDPVs circulated locally for about 7 months following the initiating oral poliovirus vaccine (OPV) dose. Our findings reinforce the point that cVDPVs can emerge and spread in isolated communities with immunity gaps and highlight the emergence risks of type 2 cVDPVs accompanying the trivalent OPV used. To solve this issue, it is recommended that type 2 OPV be removed from the trivalent OPV or that inactivated polio vaccine (IPV) be used instead. PMID:24850620

  11. Combustor exhaust-emissions and blowout-limits with diesel number 2 and jet A fuels utilizing air-atomizing and pressure atomizing nozzles

    NASA Technical Reports Server (NTRS)

    Ingebo, R. D.; Norgren, C. T.

    1975-01-01

    Experimental tests with diesel number 2 and Jet A fuels were conducted in a combustor segment to obtain comparative data on exhaust emissions and blowout limits. An air-atomizing nozzle was used to inject the fuels. Tests were also made with diesel number 2 fuel using a pressure-atomizing nozzle to determine the effectiveness of the air-atomizing nozzle in reducing exhaust emissions. Test conditions included fuel-air ratios of 0.008 to 0.018, inlet-air total pressures and temperatures of 41 to 203 newtons per square centimeter and 477 to 811 K, respectively, and a reference velocity of 21.3 meters per second. Smoke number and unburned hydrocarbons were twice as high with diesel number 2 as with Jet A fuel. This was attributed to diesel number 2 having a higher concentration of aromatics and lower volatility than Jet A fuel. Oxides of nitrogen, carbon monoxide, and blowout limits were approximately the same for the two fuels. The air-atomizing nozzle, as compared with the pressure-atomizing nozzle, reduced oxides-of-nitrogen by 20 percent, smoke number by 30 percent, carbon monoxide by 70 percent, and unburned hydrocarbons by 50 percent when used with diesel number 2 fuel.

  12. CO2 Fixation, Lipid Production, and Power Generation by a Novel Air-Lift-Type Microbial Carbon Capture Cell System.

    PubMed

    Hu, Xia; Liu, Baojun; Zhou, Jiti; Jin, Ruofei; Qiao, Sen; Liu, Guangfei

    2015-09-01

    An air-lift-type microbial carbon capture cell (ALMCC) was constructed for the first time by using an air-lift-type photobioreactor as the cathode chamber. The performance of ALMCC in fixing high concentration of CO2, producing energy (power and biodiesel), and removing COD together with nutrients was investigated and compared with the traditional microbial carbon capture cell (MCC) and air-lift-type photobioreactor (ALP). The ALMCC system produced a maximum power density of 972.5 mW·m(-3) and removed 86.69% of COD, 70.52% of ammonium nitrogen, and 69.24% of phosphorus, which indicate that ALMCC performed better than MCC in terms of power generation and wastewater treatment efficiency. Besides, ALMCC demonstrated 9.98- and 1.88-fold increases over ALP and MCC in the CO2 fixation rate, respectively. Similarly, the ALMCC significantly presented a higher lipid productivity compared to those control reactors. More importantly, the preliminary analysis of energy balance suggested that the net energy of the ALMCC system was significantly superior to other systems and could theoretically produce enough energy to cover its consumption. In this work, the established ALMCC system simultaneously achieved the high level of CO2 fixation, energy recycle, and municipal wastewater treatment effectively and efficiently. PMID:26270956

  13. Localization of type I interferon receptor limits interferon-induced TLR-3 in epithelial cells

    EPA Science Inventory

    This study aimed to expand on the role of type I IFNs in the influenza-induced upregulation of TLR3 and determine whether and how the localization of the IFN-alpha/beta receptor (IFNAR) in respiratory epithelial cells could modify IFN-induced responses. Using differentiated prima...

  14. 41 CFR 302-17.3 - Types of moving expenses or allowances covered and general limitations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-RELOCATION INCOME TAX (RIT) ALLOWANCE § 302-17.3 Types of moving expenses or allowances covered and general... law authorizes reimbursement of additional income taxes resulting from certain moving expenses... actually paid or incurred, and are not allowable as a moving expense deduction for tax purposes. The...

  15. Minimum Energy type of Air Conditioning Controlby Switching Equilibrium Point of Control Variables

    NASA Astrophysics Data System (ADS)

    Takahata, Akihiko; Uchida, Kenko; Taira, Utaro

    In this paper, we propose an algorithm realizing minimum energy control for air conditioning. In the air conditioning system, control inputs are valve-open-value of cooler, heater and humidifier, and controlled variables are indoor temperature and humidity. That is, this system has three inputs and two outputs. The main step of the minimum energy algorithm is to switch two of the three actuators, depending on setpoints, for minimizing consumption energy. We apply this algorithm to a real plant, and show validity of the algorithm.

  16. Type I interferon signaling limits reoviral tropism within the brain and prevents lethal systemic infection

    PubMed Central

    Dionne, Kalen R.; Galvin, John M.; Schittone, Stephanie A.; Clarke, Penny

    2011-01-01

    In vivo and ex vivo models of reoviral encephalitis were utilized to delineate the contribution of type I interferon (IFN) to the host’s defense against local central nervous system (CNS) viral infection and systemic viral spread. Following intracranial (i.c.) inoculation with either serotype 3 (T3) or serotype 1 (T1) reovirus, increased expression of IFN-α, IFN-β, and myxovirus-resistance protein (Mx1; a prototypical IFN stimulated gene) was observed in mouse brain tissue. Type I IFN receptor deficient mice (IFNAR−/−) had accelerated lethality, compared to wildtype (B6wt) controls, following i.c. T1 or T3 challenge. Although viral titers in the brain and eyes of reovirus infected IFNAR−/− mice were significantly increased, these mice did not develop neurologic signs or brain injury. In contrast, increased reovirus titers in peripheral tissues (liver, spleen, kidney, heart, and blood) of IFNAR−/− mice were associated with severe intestinal and liver injury. These results suggest that reovirus-infected IFNAR−/− mice succumb to peripheral disease rather than encephalitis per se. To investigate the potential role of type I IFN in brain tissue, brain slice cultures (BSCs) were prepared from IFNAR−/− mice and B6wt controls for ex vivo T3 reovirus infection. Compared to B6wt controls, reoviral replication and virus-induced apoptosis were enhanced in IFNAR−/− BSCs indicating that a type I IFN response, initiated by resident CNS cells, mediates innate viral immunity within the brain. T3 reovirus tropism was extended in IFNAR−/− brains to include dentate neurons, ependymal cells, and meningeal cells indicating that reovirus tropism within the CNS is dependent upon type I interferon signaling. PMID:21671121

  17. Prevalence of 'Candidatus Accumulibacter phosphatis' type II under phosphate limiting conditions.

    PubMed

    Welles, L; Lopez-Vazquez, C M; Hooijmans, C M; van Loosdrecht, M C M; Brdjanovic, D

    2016-12-01

    P-limitation in enhanced biological phosphorus removal (EBPR) systems fed with acetate, has generally been considered as a condition leading to enrichment of organisms of the genotype' Candidatus Competibacter phosphatis' expressing the glycogen-accumulating organisms (GAO) phenotype. Recent studies have demonstrated in short-term experiments that organisms of the genotype 'Candidatus Accumulibacter phosphatis' clade I and II, known to express the polyphosphate-accumulating organisms (PAO) phenotype can switch to the GAO phenotype when poly-P is absent, but are performing the HAc-uptake at lower kinetic rates, where clade I showed the lowest rates. The objective of this study was to verify whether organisms of the genotype 'Candidatus Accumulibacter phosphatis' can also be enriched under P-limiting conditions while expressing a GAO phenotype and more specifically to see which specific clade prevails. A sequencing batch reactor was inoculated with activated sludge to enrich an EBPR culture for a cultivation period of 128 days (16 times the solids retention time) under P-limiting conditions. A mixed culture was obtained comprising of 49 % 'Candidatus Accumulibacter phosphatis' clade II and 46 % 'Candidatus Competibacter phosphatis'. The culture performed a full GAO metabolism for anaerobic HAc-uptake, but was still able to switch to a PAO metabolism, taking up excessive amounts of phosphate during the aerobic phase when it became available in the influent. These findings show that P-limitation, often used as strategy for enrichment of 'Candidatus Competibacter phosphatis', does not always lead to enrichment of only 'Candidatus Competibacter phosphatis'. Furthermore, it demonstrates that 'Candidatus Accumulibacter phosphatis' are able to proliferate in activated sludge systems for periods of up to 128 days or longer when the influent phosphate concentrations are just enough for assimilation purposes and no poly-P is formed. The 'Candidatus Accumulibacter

  18. Fabrication of air-stable n-type carbon nanotube thin-film transistors on flexible substrates using bilayer dielectrics.

    PubMed

    Li, Guanhong; Li, Qunqing; Jin, Yuanhao; Zhao, Yudan; Xiao, Xiaoyang; Jiang, Kaili; Wang, Jiaping; Fan, Shoushan

    2015-11-14

    Single-walled carbon nanotube (SWNT) thin-film transistors hold great potential for flexible electronics. However, fabrication of air-stable n-type devices by methods compatible with standard photolithography on flexible substrates is challenging. Here, we demonstrated that by using a bilayer dielectric structure of MgO and atomic layer deposited (ALD) Al2O3 or HfO2, air-stable n-type devices can be obtained. The mechanism for conduction type conversion was elucidated and attributed to the hole depletion in SWNT, the decrease of the trap state density by MgO assimilating adsorbed water molecules in the vicinity of SWNT, and the energy band bending because of the positive fixed charges in the ALD layer. The key advantage of the method is the relatively low temperature (120 or 90 °C) required here for the ALD process because we need not employ this step to totally remove the absorbates on the SWNTs. This advantage facilitates the integration of both p-type and n-type transistors through a simple lift off process and compact CMOS inverters were demonstrated. We also demonstrated that the doping of SWNTs in the channel plays a more important role than the Schottky barriers at the metal contacts in carbon nanotube thin-film transistors, unlike the situation in individual SWNT-based transistors. PMID:26451806

  19. Type-Ia SN 2016coj - limits on progenitors from pre-explosion HST images

    NASA Astrophysics Data System (ADS)

    Friedmann, Matan; Maoz, Dan

    2016-07-01

    We have analyzed archival Hubble Space Telescope WFPC2 images of the site of the Type-Ia SN2016coj (ATEL#9095, #9193) in NGC 4125 in five filters taken on several pre-explosion epochs: F336W from 2009 (~U band, 6600 s total), F439W from 2009 (~B band, 2100 s total), F555W from 1999 (~V band, 1400 s total), F702W from 1997 (~R band, 1000 s total) and F814W (~I band, 2000 s total).

  20. Influence of a voltage compensation type active superconducting fault current limiter on the transient stability of power system

    NASA Astrophysics Data System (ADS)

    Chen, L.; Tang, Y. J.; Shi, J.; Chen, N.; Song, M.; Cheng, S. J.; Hu, Y.; Chen, X. S.

    2009-10-01

    We have proposed a voltage compensation type active superconducting fault current limiter (SFCL). In this paper, the influence of the SFCL on the transient stability of power system is investigated. For the typical one-machine infinite-bus system, the power-angle characteristics of generator with SFCL are studied in different working conditions, and the transient physical process is analyzed. Using MATLAB SIMULINK, the power-angle swing curves are simulated under different current-limiting modes, fault types and fault clearance times. The results show that the proposed SFCL can effectively reduce the transient swing amplitude of rotor and extend the critical clearance time under mode 1, compared with mode 2 and mode 3 having few effects on enhancing the transient stability.

  1. Type III Collagen Directs Stromal Organization and Limits Metastasis in a Murine Model of Breast Cancer

    PubMed Central

    Brisson, Becky K.; Mauldin, Elizabeth A.; Lei, Weiwei; Vogel, Laurie K.; Power, Ashley M.; Lo, Albert; Dopkin, Derek; Khanna, Chand; Wells, Rebecca G.; Puré, Ellen; Volk, Susan W.

    2016-01-01

    Breast cancer metastasis is the leading cause of cancer-related deaths in women worldwide. Collagen in the tumor microenvironment plays a crucial role in regulating tumor progression. We have shown that type III collagen (Col3), a component of tumor stroma, regulates myofibroblast differentiation and scar formation after cutaneous injury. During the course of these wound-healing studies, we noted that tumors developed at a higher frequency in Col3+/− mice compared to wild-type littermate controls. We, therefore, examined the effect of Col3 deficiency on tumor behavior, using the murine mammary carcinoma cell line 4T1. Notably, tumor volume and pulmonary metastatic burden after orthotopic injection of 4T1 cells were increased in Col3+/− mice compared to Col3+/+ littermates. By using murine (4T1) and human (MDA-MB-231) breast cancer cells grown in Col3-poor and Col3-enriched microenvironments in vitro, we found that several major events of the metastatic process were suppressed by Col3, including adhesion, invasion, and migration. In addition, Col3 deficiency increased proliferation and decreased apoptosis of 4T1 cells both in vitro and in primary tumors in vivo. Mechanistically, Col3 suppresses the procarcinogenic microenvironment by regulating stromal organization, including density and alignment of fibrillar collagen and myofibroblasts. We propose that Col3 plays an important role in the tumor microenvironment by suppressing metastasis-promoting characteristics of the tumor-associated stroma. PMID:25795282

  2. Limited Effects of Muc1 Deficiency on Mouse Adenovirus Type 1 Respiratory Infection

    PubMed Central

    Nguyen, Y; Procario, Megan C.; Ashley, Shanna L.; O'Neal, Wanda K.; Pickles, Raymond J.; Weinberg, Jason B.

    2011-01-01

    Muc1 (MUC1 in humans) is a membrane-tethered mucin that exerts anti-inflammatory effects in the lung during bacterial infection. Muc1 and other mucins are also likely to form a protective barrier in the lung. We used mouse adenovirus type 1 (MAV-1, also known as MAdV-1) to determine the role of Muc1 in the pathogenesis of an adenovirus in its natural host. Following intranasal inoculation of wild type mice, we detected increased TNF-α, a cytokine linked to Muc1 production, but no consistent changes in the production of lung Muc1, Muc5ac or overall lung mucus production. Viral loads were modestly higher in the lungs of Muc1−/− mice compared to Muc1+/+ mice at several early time points but decreased to similar levels by 14 days post infection in both groups. However, cellular inflammation and the expression of CXCL1, CCL5, and CCL2 did not significantly differ between Muc1−/− and Muc1+/+ mice. Our data therefore suggest that Muc1 may contribute to a physical barrier that protects against MAV-1 respiratory infection. However, our data do not reveal an anti-inflammatory effect of Muc1 that contributes to MAV-1 pathogenesis.. PMID:21816184

  3. [Limitations of insulin-dependent drugs in the treatment of type 2 diabetes mellitus].

    PubMed

    Valerón, Pino Fuente; de Pablos-Velasco, Pedro L

    2013-09-01

    In this study, we review the efficacy and safety limitations of insulin-dependent oral antidiabetic agents. In terms of efficiency, the main drawback of metformin, sulfonylureas, gliptins and -to a lesser extent-glitazones is durability. No drug per se is able to maintain stable blood glucose control for years. Metformin, sulfonylureas and gliptins have demonstrated safety. Experience with the first two drug groups is more extensive. The main adverse effect of metformin is gastrointestinal discomfort. Major concerns related to the use of sulfonylureas are hypoglycemia and weight gain. The use of pioglitazone has been associated with an increased risk of bladder cancer, edema, heart failure, weight gain, and distal bone fractures in postmenopausal women. The most common adverse reactions associated with glucagon-like peptide-1 agonists are gastrointestinal discomfort that sometimes leads to treatment discontinuation. PMID:24444520

  4. Modelling near subsurface temperature with mixed type boundary condition for transient air temperature and vertical groundwater flow

    NASA Astrophysics Data System (ADS)

    Kumar, Rajeev Ranjan; Ramana, D. V.; Singh, R. N.

    2012-10-01

    Near-subsurface temperatures have signatures of climate change. Thermal models of subsurface have been constructed by prescribing time dependent Dirichlet type boundary condition wherein the temperature at the soil surface is prescribed and depth distribution of temperature is obtained. In this formulation it is not possible to include the relationship between air temperatures and the temperature of soil surface. However, if one uses a Robin type boundary condition, a transfer coefficient relates the air and soil surface temperatures which helps to determine both the temperature at the surface and at depth given near surface air temperatures. This coefficient is a function of meteorological conditions and is readily available. We have developed such a thermal model of near subsurface region which includes both heat conduction and advection due to groundwater flows and have presented numerical results for changes in the temperature-depth profiles for different values of transfer coefficient and groundwater flux. There are significant changes in temperature and depth profiles due to changes in the transfer coefficient and groundwater flux. The analytical model will find applications in the interpretation of the borehole geothermal data to extract both climate and groundwater flow signals.

  5. Current limiting behavior in three-phase transformer-type SFCLs using an iron core according to variety of fault

    NASA Astrophysics Data System (ADS)

    Cho, Yong-Sun; Jung, Byung-Ik; Ha, Kyoung-Hun; Choi, Soo-Geun; Park, Hyoung-Min; Choi, Hyo-Sang

    To apply the superconducting fault current limiter (SFCL) to the power system, the reliability of the fault-current-limiting operation must be ensured in diverse fault conditions. The SFCL must also be linked to the operation of the high-speed recloser in the power system. In this study, a three-phase transformer-type SFCL, which has a neutral line to improve the simultaneous quench characteristics of superconducting elements, was manufactured to analyze the fault-current-limiting characteristic according to the single, double, and triple line-to-ground faults. The transformer-type SFCL, wherein three-phase windings are connected to one iron core, reduced the burden on the superconducting element as the superconducting element on the sound phase was also quenched in the case of the single line-to-ground fault. In the case of double or triple line-to-ground faults, the flux from the faulted phase winding was interlinked with other faulted or sound phase windings, and the fault-current-limiting rate decreased because the windings of three phases were inductively connected by one iron core.

  6. Theoretical limits of thermoelectric figure of merit in n -type TiO2 polymorphs

    NASA Astrophysics Data System (ADS)

    Bayerl, Dylan; Kioupakis, Emmanouil

    2015-04-01

    We calculate the conduction-band structures and n -type thermoelectric transport properties for the TiO2 polymorphs rutile, anatase, and brookite from first principles within the constant-relaxation-time approximation. Although the Seebeck coefficient is nearly isotropic in all polymorphs, the power factor is anisotropic and takes its largest values along [100] in rutile and anatase and along [010] in brookite. We also identify the free-carrier concentrations and temperatures that maximize the power factor. Our results for the theoretical upper bounds of the figure of merit at high temperature show that optimized rutile exhibits thermoelectric conversion efficiency that is superior to anatase and brookite and can reach values desirable for waste-heat recovery applications.

  7. Limits in the characteristic-function description of non-Lindblad-type open quantum systems

    SciTech Connect

    Maniscalco, Sabrina

    2005-08-15

    In this paper I investigate the usability of the characteristic functions for the description of the dynamics of open quantum systems focussing on non-Lindblad-type master equations. I consider, as an example, a non-Markovian generalized master equation containing a memory kernel which may lead to nonphysical time evolutions characterized by negative values of the density matrix diagonal elements [S. M. Barnett and S. Stenholm, Phys. Rev. A 64, 033808 (2001)]. The main result of the paper is to demonstrate that there exist situations in which the symmetrically ordered characteristic function is perfectly well-defined while the corresponding density matrix loses positivity. Therefore, nonphysical situations may not show up in the characteristic function. As a consequence, the characteristic function cannot be considered an alternative complete description of the non-Lindblad dynamics.

  8. Limited subsolidus diffusion in type B1 CAI: Evidence from Ti distribution in spinel

    NASA Technical Reports Server (NTRS)

    Meeker, G. P.; Quick, J. E.; Paque, Julie M.

    1993-01-01

    Most models of calcium aluminum-rich inclusions (CAI) have focused on early stages of formation by equilibrium crystallization of a homogeneous liquid. Less is known about the subsolidus cooling history of CAI. Chemical and isotopic heterogeneties on a scale of tens to hundreds of micrometers (e.g. MacPherson et al. (1989) and Podosek, et al. (1991)) suggest fairly rapid cooling with a minimum of subsolidus diffusion. However, transmission electron microscopy indicates that solid state diffusion may have been an important process at a smaller scale (Barber et al. 1984). If so, chemical evidence for diffusion could provide constraints on cooling times and temperatures. With this in mind, we have begun an investigation of the Ti distribution in spinels from two type B1 CAI from Allende to determine if post-crystallization diffusion was a significant process. The type B1 CAIs, 3529Z and 5241 have been described by Podosek et al. (1991) and by El Goresy et al. (1985) and MacPherson et al. (1989). We have analyzed spinels in these inclusions using the electron microprobe. These spinels are generally euhedral, range in size from less than 10 to 15 micron and are poikilitically enclosed by millimeter-sized pyroxene, melilite, and anorthite. Analyses were obtained from both the mantles and cores of the inclusions. Compositions of pyroxene in the vicinity of individual spinel grains were obtained by analyzing at least two points on opposite sides of the spinel and averaging the compositions. The pyroxene analyses were obtained within 15 microns of the spinel-pyroxene interface. No compositional gradients were observed within single spinel crystals. Ti concentrations in spinels included within pyroxene, melilite, and anorthite are presented.

  9. Effect of Water-Alcohol Injection and Maximum Economy Spark Advance on Knock-Limited Performance and Fuel Economy of a Large Air-Cooled Cylinder

    NASA Technical Reports Server (NTRS)

    Heinicke, Orville H.; Vandeman, Jack E.

    1945-01-01

    An investigation was conducted to determine the effect of a coolant solution of 25 percent ethyl alcohol, 25 percent methyl alcohol, and 50 percent water by volume and maximum-economy spark advance on knock-limited performance and fuel economy of a large air-cooled cylinder. The knock-limited performance of the cylinder at engine speeds of 2100 and 2500 rpm was determined for coolant-fuel ratios of 0.0, 0.2, and 0.4. The effect of water-alcohol injection on fuel economy was determined in constant charge-air flow tests. The tests were conducted at a spark advance of 20 deg B.T.C. and maximum-economy spark advance.

  10. A New Type of Steady and Stable, Laminar, Premixed Flame in Ultra-Lean, Hydrogen-Air Combustion

    SciTech Connect

    Grcar, Joseph F; Grcar, Joseph F

    2008-06-30

    Ultra-lean, hydrogen-air mixtures are found to support another kind of laminar flame that is steady and stable beside flat flames and flame balls. Direct numerical simulations are performed of flames that develop into steadily and stably propagating cells. These cells were the original meaning of the word"flamelet'' when they were observed in lean flammability studies conducted early in the development of combustion science. Several aspects of these two-dimensional flame cells are identified and are contrasted with the properties of one-dimensional flame balls and flat flames. Although lean hydrogen-air flames are subject to thermo-diffusive effects, in this case the result is to stabilize the flame rather than to render it unstable. The flame cells may be useful as basic components of engineering models for premixed combustion when the other types of idealized flames are inapplicable.

  11. Study of recovery characteristics of 2nd generation HTS tapes with different stabilizers for resistive type superconducting fault current limiters

    NASA Astrophysics Data System (ADS)

    Sheng, Jie; Zeng, Weina; Ma, Jun; Yao, Zhihao; Li, Zhuyong; Jin, Zhijian; Hong, Zhiyong

    2016-02-01

    The resistive type superconducting fault current limiter (SFCL) is one of the most important superconducting power applications nowadays. As known, this type of SFCL is settled directly in the power transmission line. When a short fault happens, the temperature of the superconductors in the SFCL will increase sharply due to the huge generated heat. This means the superconductors need time to recover the superconducting properties and be ready for the next short fault. So the recovery characteristics become one of the most crucial features of the resistive type SFCL. In this paper, several different kinds of measuring methods are presented to calculate the recovery time of the HTS tapes, and comparison of these methods is also carried out by a standard test. On basis of this, samples with different kinds of stabilizers are used to explore the influence of stabilizer on their recovery characteristics. In addition, the influence of the encapsulation technology is also discussed in this paper.

  12. Calculations of relative optical air masses for various aerosol types and minor gases in Arctic and Antarctic atmospheres

    NASA Astrophysics Data System (ADS)

    Tomasi, Claudio; Petkov, Boyan H.

    2014-02-01

    The dependence functions of relative optical air mass on apparent solar zenith angle θ have been calculated over the θ < 87° range for the vertical profiles of wet-air molecular number density in the Arctic and Antarctic atmospheres, extinction coefficients of different aerosol types, and molecular number density of water vapor, ozone, nitrogen dioxide, and oxygen dimer. The calculations were made using as weight functions the seasonal average vertical profiles of (i) pressure and temperature derived from multiyear sets of radiosounding measurements performed at Ny-Ålesund, Alert, Mario Zucchelli, and Neumayer stations; (ii) volume extinction coefficients of background summer aerosol, Arctic haze, and Kasatochi and Pinatubo volcanic aerosol measured with lidars or balloon-borne samplings; and (iii) molecular number concentrations of the above minor gases, derived from radiosonde, ozonesonde, and satellite-based observations. The air mass values were determined using a formula based on a realistic atmospheric air-refraction model. They were systematically checked by comparing their mutual differences with the uncertainties arising from the seasonal and daily variations in pressure and temperature conditions within the various ranges, where aerosol and gases attenuate the solar radiation most efficiently. The results provide evidence that secant-approximated and midlatitude air mass values are inappropriate for analyzing the Sun photometer measurements performed at polar sites. They indicate that the present evaluations can be reliably used to estimate the aerosol optical depth from the Arctic and Antarctic measurements of total optical depth, after appropriate corrections for the Rayleigh scattering and gaseous absorption optical depths.

  13. Limitations to soybean photosynthesis at elevated carbon dioxide in free-air enrichment and open top chamber systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It has been suggested that the stimulation of soybean photosynthesis by elevated carbon dioxide concentration was less in free-air carbon dioxide enrichment (FACE) systems than in open top chambers (OTC). However, this has not been tested using the same cultivars grown in the same location. We tes...

  14. Commuters’ Exposure to Particulate Matter Air Pollution Is Affected by Mode of Transport, Fuel Type, and Route

    PubMed Central

    Zuurbier, Moniek; Hoek, Gerard; Oldenwening, Marieke; Lenters, Virissa; Meliefste, Kees; van den Hazel, Peter; Brunekreef, Bert

    2010-01-01

    Background Commuters are exposed to high concentrations of air pollutants, but little quantitative information is currently available on differences in exposure between different modes of transport, routes, and fuel types. Objectives The aim of our study was to assess differences in commuters’ exposure to traffic-related air pollution related to transport mode, route, and fuel type. Methods We measured particle number counts (PNCs) and concentrations of PM2.5 (particulate matter ≤ 2.5 μm in aerodynamic diameter), PM10, and soot between June 2007 and June 2008 on 47 weekdays, from 0800 to 1000 hours, in diesel and electric buses, gasoline- and diesel-fueled cars, and along two bicycle routes with different traffic intensities in Arnhem, the Netherlands. In addition, each-day measurements were taken at an urban background location. Results We found that median PNC exposures were highest in diesel buses (38,500 particles/cm3) and for cyclists along the high-traffic intensity route (46,600 particles/cm3) and lowest in electric buses (29,200 particles/cm3). Median PM10 exposure was highest from diesel buses (47 μg/m3) and lowest along the high- and low-traffic bicycle routes (39 and 37 μg/m3). The median soot exposure was highest in gasoline-fueled cars (9.0 × 10−5/m), diesel cars (7.9 × 10−5/m), and diesel buses (7.4 × 10−5/m) and lowest along the low-traffic bicycle route (4.9 × 10−5/m). Because the minute ventilation (volume of air per minute) of cyclists, which we estimated from measured heart rates, was twice the minute ventilation of car and bus passengers, we calculated that the inhaled air pollution doses were highest for cyclists. With the exception of PM10, we found that inhaled air pollution doses were lowest for electric bus passengers. Conclusions Commuters’ rush hour exposures were significantly influenced by mode of transport, route, and fuel type. PMID:20185385

  15. VOCs Emissions from Multiple Wood Pellet Types and Concentrations in Indoor Air

    PubMed Central

    Soto-Garcia, Lydia; Ashley, William J.; Bregg, Sandar; Walier, Drew; LeBouf, Ryan; Hopke, Philip K.; Rossner, Alan

    2016-01-01

    Wood pellet storage safety is an important aspect for implementing woody biomass as a renewable energy source. When wood pellets are stored indoors in large quantities (tons) in poorly ventilated spaces in buildings, such as in basements, off-gassing of volatile organic compounds (VOCs) can significantly affect indoor air quality. To determine the emission rates and potential impact of VOC emissions, a series of laboratory and field measurements were conducted using softwood, hardwood, and blended wood pellets manufactured in New York. Evacuated canisters were used to collect air samples from the headspace of drums containing pellets and then in basements and pellet storage areas of homes and small businesses. Multiple peaks were identified during GC/MS and GC/FID analysis, and four primary VOCs were characterized and quantified: methanol, pentane, pentanal, and hexanal. Laboratory results show that total VOCs (TVOCs) concentrations for softwood (SW) were statistically (p < 0.02) higher than blended or hardwood (HW) (SW: 412 ± 25; blended: 203 ± 4; HW: 99 ± 8, ppb). The emission rate from HW was the fastest, followed by blended and SW, respectively. Emissions rates were found to range from 10−1 to 10−5 units, depending upon environmental factors. Field measurements resulted in airborne concentrations ranging from 67 ± 8 to 5000 ± 3000 ppb of TVOCs and 12 to 1500 ppb of aldehydes, with higher concentrations found in a basement with a large fabric bag storage unit after fresh pellet delivery and lower concentrations for aged pellets. These results suggest that large fabric bag storage units resulted in a substantial release of VOCs into the building air. Occupants of the buildings tested discussed concerns about odor and sensory irritation when new pellets were delivered. The sensory response was likely due to the aldehydes. PMID:27022205

  16. Formation of H-type liquid crystal dimer at air-water interface

    SciTech Connect

    Karthik, C. Gupta, Adbhut Joshi, Aditya Manjuladevi, V. Gupta, Raj Kumar; Varia, Mahesh C.; Kumar, Sandeep

    2014-04-24

    We have formed the Langmuir monolayer of H-shaped Azo linked liquid crystal dimer molecule at the air-water interface. Isocycles of the molecule showed hysteresis suggesting the ir-reversible nature of the monolayer formed. The thin film deposited on the silicon wafer was characterized using Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscopy (FESEM). The images showed uniform domains of the dimer molecule. We propose that these molecules tend to take book shelf configuration in the liquid phase.

  17. Bisthiadiazole-Fused Tetraazapentacenequinone: An Air-Stable Solution-Processable n-Type Organic Semiconductor.

    PubMed

    Cortizo-Lacalle, Diego; Gozalvez, Cristian; Olano, Mikel; Sun, Xiangnan; Melle-Franco, Manuel; Hueso, Luis E; Mateo-Alonso, Aurelio

    2015-12-01

    The synthesis and characterization of a tetraazapentacenequinone fused to two thiadiazoles is reported. This linear derivative constituting seven fused rings shows a very low LUMO level (-4.46 eV) and a low HOMO-LUMO gap (1.77 eV). Its high solubility, endowed by four triisopropylsilyl groups, allows the fabrication of air-stable field-effect transistors by liquid deposition methods that show electron mobilities up to 2.42 × 10(-3) cm(2) V(-1) s(-1) without any device optimization. PMID:26588192

  18. Air backed mandrel type fiber optic hydrophone with low noise floor

    NASA Astrophysics Data System (ADS)

    Rajesh, R.; V, Sreehari C.; N, Praveen Kumar; Awasthi, R. L.; K, Vivek; B, Vishnu M.; Santhanakrishnan, T.; Moosad, K. P. B.; Mathew, Basil

    2014-10-01

    Low noise fiber optic hydrophone based on optical fiber coil wound on air-backed mandrel was developed. The sensor can be effectively used for underwater acoustic sensing. The design and characterization of the hydrophone is illustrated in this paper. A fiber Mach-Zehnder Interferometer (MZI) was developed and coupled with a Distributed Feedback (DFB) fiber laser source and an optical phase demodulation system, with an active modulation in one of the arms. The sensor head design was optimized to achieve noise spectral density <10 μrad/√Hz, for yielding sufficient sensitivity to sense acoustic pressure close to Deep Sea Sate Zero (DSS0).

  19. Fabrication of air-stable n-type carbon nanotube thin-film transistors on flexible substrates using bilayer dielectrics

    NASA Astrophysics Data System (ADS)

    Li, Guanhong; Li, Qunqing; Jin, Yuanhao; Zhao, Yudan; Xiao, Xiaoyang; Jiang, Kaili; Wang, Jiaping; Fan, Shoushan

    2015-10-01

    Single-walled carbon nanotube (SWNT) thin-film transistors hold great potential for flexible electronics. However, fabrication of air-stable n-type devices by methods compatible with standard photolithography on flexible substrates is challenging. Here, we demonstrated that by using a bilayer dielectric structure of MgO and atomic layer deposited (ALD) Al2O3 or HfO2, air-stable n-type devices can be obtained. The mechanism for conduction type conversion was elucidated and attributed to the hole depletion in SWNT, the decrease of the trap state density by MgO assimilating adsorbed water molecules in the vicinity of SWNT, and the energy band bending because of the positive fixed charges in the ALD layer. The key advantage of the method is the relatively low temperature (120 or 90 °C) required here for the ALD process because we need not employ this step to totally remove the absorbates on the SWNTs. This advantage facilitates the integration of both p-type and n-type transistors through a simple lift off process and compact CMOS inverters were demonstrated. We also demonstrated that the doping of SWNTs in the channel plays a more important role than the Schottky barriers at the metal contacts in carbon nanotube thin-film transistors, unlike the situation in individual SWNT-based transistors.Single-walled carbon nanotube (SWNT) thin-film transistors hold great potential for flexible electronics. However, fabrication of air-stable n-type devices by methods compatible with standard photolithography on flexible substrates is challenging. Here, we demonstrated that by using a bilayer dielectric structure of MgO and atomic layer deposited (ALD) Al2O3 or HfO2, air-stable n-type devices can be obtained. The mechanism for conduction type conversion was elucidated and attributed to the hole depletion in SWNT, the decrease of the trap state density by MgO assimilating adsorbed water molecules in the vicinity of SWNT, and the energy band bending because of the positive fixed

  20. Air stable organic salt as an n-type dopant for efficient and stable organic light-emitting diodes.

    PubMed

    Bin, Zhengyang; Duan, Lian; Qiu, Yong

    2015-04-01

    Air-stable and low-temperature-evaporable n-type dopants are highly desired for efficient and stable organic light-emitting diodes (OLEDs). In this work, 2-(2-Methoxyphenyl)-1,3-dimethyl-1H-benzoimidazol-3-ium iodide (o-MeO-DMBI-I), a thermally decomposable precursor of organic radical o-MeO-DMBI, has been employed as a novel n-type dopant in OLEDs, because of its air stability, low decomposition temperature, and lack of atom diffusion. The n-type electrical doping is evidenced by the rapid increase in current density of electron-only devices and the large improvement in conductivity, originated from increased electron concentration in electron-transport layer (ETL) and reduced electron injection barrier. A highly efficient and stable OLED is created using o-MeO-DMBI as an n-type dopant in Bphen. Compared with the control device with its high-temperature-evaporable n-type dopant cesium carbonate (Cs2CO3), o-MeO-DMBI-doped device showed an incredible boom in current efficiency from 28.6 to 42.2 cd/A. Moreover, the lifetime (T(70%)) of o-MeO-DMBI-doped device is 45 h, more than 20 times longer than that of the Cs2CO3-doped device (2 h). The enhanced efficiency and stability are attributed to the improved balance of holes and electrons in the emissive layer, and the eliminated atom diffusion of cesium. PMID:25768295

  1. Differential regulation of two types of monogalactosyldiacylglycerol synthase in membrane lipid remodeling under phosphate-limited conditions in sesame plants

    PubMed Central

    Shimojima, Mie; Watanabe, Takahide; Madoka, Yuka; Koizumi, Ryota; Yamamoto, Masayuki P.; Masuda, Kyojiro; Yamada, Kyoji; Masuda, Shinji; Ohta, Hiroyuki

    2013-01-01

    Phosphate (Pi) limitation causes drastic lipid remodeling in plant membranes. Glycolipids substitute for the phospholipids that are degraded, thereby supplying Pi needed for essential biological processes. Two major types of remodeling of membrane lipids occur in higher plants: whereas one involves an increase in the concentration of sulfoquinovosyldiacylglycerol in plastids to compensate for a decreased concentration of phosphatidylglycerol, the other involves digalactosyldiacylglycerol (DGDG) synthesis in plastids and the export of DGDG to extraplastidial membranes to compensate for reduced abundances of phospholipids. Lipid remodeling depends on an adequate supply of monogalactosyldiacylglycerol (MGDG), which is a substrate that supports the elevated rate of DGDG synthesis that is induced by low Pi availability. Regulation of MGDG synthesis has been analyzed most extensively using the model plant Arabidopsis thaliana, although orthologous genes that encode putative MGDG synthases exist in photosynthetic organisms from bacteria to higher plants. We recently hypothesized that two types of MGDG synthase diverged after the appearance of seed plants. This divergence might have both enabled plants to adapt to a wide range of Pi availability in soils and contributed to the diversity of seed plants. In the work presented here, we found that membrane lipid remodeling also takes place in sesame, which is one of the most common traditional crops grown in Asia. We identified two types of MGDG synthase from sesame (encoded by SeMGD1 and SeMGD2) and analyzed their enzymatic properties. Our results show that both genes correspond to the Arabidopsis type-A and -B isoforms of MGDG synthase. Notably, whereas Pi limitation up-regulates only the gene encoding the type-B isoform of Arabidopsis, low Pi availability up-regulates the expression of both SeMGD1 and SeMGD2. We discuss the significance of the different responses to low Pi availability in sesame and Arabidopsis. PMID

  2. Grown-in defects limiting the bulk lifetime of p-type float-zone silicon wafers

    NASA Astrophysics Data System (ADS)

    Grant, N. E.; Rougieux, F. E.; Macdonald, D.; Bullock, J.; Wan, Y.

    2015-02-01

    We investigate a recombination active grown-in defect limiting the bulk lifetime (τbulk) of high quality float-zone (FZ) p-type silicon wafers. After annealing the samples at temperatures between 80 °C and 400 °C, τbulk was found to increase from ˜500 μs to ˜1.5 ms. By isochronal annealing the p-type samples between 80 °C and 400 °C for 30 min, the annihilation energy (Eann) of the defect was determined to be 0.3 < Eann < 0.7 eV. When the annihilated samples were phosphorus gettered at 880 °C or subject to 0.2 sun illumination for 24 h, τbulk was found to degrade. However, when the samples were subsequently annealed at temperatures between 250 and 400 °C, the defect could be re-annihilated. The experimental results suggest that the defect limiting the lifetime in the p-type FZ silicon is not related to fast diffusing metallic impurities but rather to a lattice-impurity or an impurity-impurity metastable defect.

  3. Crystal Structure of Barley Limit Dextrinase-Limit Dextrinase Inhibitor (LD-LDI) Complex Reveals Insights into Mechanism and Diversity of Cereal Type Inhibitors*

    PubMed Central

    Møller, Marie S.; Vester-Christensen, Malene B.; Jensen, Johanne M.; Hachem, Maher Abou; Henriksen, Anette; Svensson, Birte

    2015-01-01

    Molecular details underlying regulation of starch mobilization in cereal seed endosperm remain unknown despite the paramount role of this process in plant growth. The structure of the complex between the starch debranching enzyme barley limit dextrinase (LD), hydrolyzing α-1,6-glucosidic linkages, and its endogenous inhibitor (LDI) was solved at 2.7 Å. The structure reveals an entirely new and unexpected binding mode of LDI as compared with previously solved complex structures of related cereal type family inhibitors (CTIs) bound to glycoside hydrolases but is structurally analogous to binding of dual specificity CTIs to proteases. Site-directed mutagenesis establishes that a hydrophobic cluster flanked by ionic interactions in the protein-protein interface is vital for the picomolar affinity of LDI to LD as assessed by analysis of binding by using surface plasmon resonance and also supported by LDI inhibition of the enzyme activity. A phylogenetic analysis identified four LDI-like proteins in cereals among the 45 sequences from monocot databases that could be classified as unique CTI sequences. The unprecedented binding mechanism shown here for LDI has likely evolved in cereals from a need for effective inhibition of debranching enzymes having characteristic open active site architecture. The findings give a mechanistic rationale for the potency of LD activity regulation and provide a molecular understanding of the debranching events associated with optimal starch mobilization and utilization during germination. This study unveils a hitherto not recognized structural basis for the features endowing diversity to CTIs. PMID:25792743

  4. Crystal structure of barley limit dextrinase-limit dextrinase inhibitor (LD-LDI) complex reveals insights into mechanism and diversity of cereal type inhibitors.

    PubMed

    Møller, Marie S; Vester-Christensen, Malene B; Jensen, Johanne M; Hachem, Maher Abou; Henriksen, Anette; Svensson, Birte

    2015-05-15

    Molecular details underlying regulation of starch mobilization in cereal seed endosperm remain unknown despite the paramount role of this process in plant growth. The structure of the complex between the starch debranching enzyme barley limit dextrinase (LD), hydrolyzing α-1,6-glucosidic linkages, and its endogenous inhibitor (LDI) was solved at 2.7 Å. The structure reveals an entirely new and unexpected binding mode of LDI as compared with previously solved complex structures of related cereal type family inhibitors (CTIs) bound to glycoside hydrolases but is structurally analogous to binding of dual specificity CTIs to proteases. Site-directed mutagenesis establishes that a hydrophobic cluster flanked by ionic interactions in the protein-protein interface is vital for the picomolar affinity of LDI to LD as assessed by analysis of binding by using surface plasmon resonance and also supported by LDI inhibition of the enzyme activity. A phylogenetic analysis identified four LDI-like proteins in cereals among the 45 sequences from monocot databases that could be classified as unique CTI sequences. The unprecedented binding mechanism shown here for LDI has likely evolved in cereals from a need for effective inhibition of debranching enzymes having characteristic open active site architecture. The findings give a mechanistic rationale for the potency of LD activity regulation and provide a molecular understanding of the debranching events associated with optimal starch mobilization and utilization during germination. This study unveils a hitherto not recognized structural basis for the features endowing diversity to CTIs. PMID:25792743

  5. Air/sea DMS gas transfer in the North Atlantic: evidence for limited interfacial gas exchange at high wind speed

    NASA Astrophysics Data System (ADS)

    Bell, T. G.; De Bruyn, W.; Miller, S. D.; Ward, B.; Christensen, K.; Saltzman, E. S.

    2013-05-01

    Shipboard measurements of eddy covariance DMS air/sea fluxes and seawater concentration were carried out in the North Atlantic bloom region in June/July 2011. Gas transfer coefficients (k660) show a linear dependence on mean horizontal wind speed at wind speeds up to 11 m s-1. At higher wind speeds the relationship between k660 and wind speed weakens. At high winds, measured DMS fluxes were lower than predicted based on the linear relationship between wind speed and interfacial stress extrapolated from low to intermediate wind speeds. In contrast, the transfer coefficient for sensible heat did not exhibit this effect. The apparent suppression of air/sea gas flux at higher wind speeds appears to be related to sea state, as determined from shipboard wave measurements. These observations are consistent with the idea that long waves suppress near surface water side turbulence, and decrease interfacial gas transfer. This effect may be more easily observed for DMS than for less soluble gases, such as CO2, because the air/sea exchange of DMS is controlled by interfacial rather than bubble-mediated gas transfer under high wind speed conditions.

  6. Spatiotemporal variations of air pollutants (O3, NO2, SO2, CO, PM10, and VOCs) with land-use types

    NASA Astrophysics Data System (ADS)

    Yoo, J.-M.; Jeong, M.-J.; Kim, D.; Stockwell, W. R.; Yang, J.-H.; Shin, H.-W.; Lee, M.-I.; Song, C.-K.; Lee, S.-D.

    2015-09-01

    The spatiotemporal variations of surface air pollutants (O3, NO2, SO2, CO, and PM10) with four land-use types, residence (R), commerce (C), industry (I) and greenbelt (G), have been investigated at 283 stations in South Korea during 2002-2013, using routinely observed data. The volatile organic compound (VOC) data at nine photochemical pollutant monitoring stations available since 2007 were utilized in order to examine their effect on the ozone chemistry. The land-use types, set by the Korean government, were generally consistent with the satellite-derived land covers and with the previous result showing anti-correlation between O3 and NO2 in diverse urban areas. The relationship between the two pollutants in the Seoul Metropolitan Area (SMA) residence land-use areas was substantially different from that outside of the SMA, probably due to the local differences in vehicle emissions. The highest concentrations of air pollutants in the diurnal, weekly, and annual cycles were found in industry for SO2 and PMPM10, in commerce for NO2 and CO, and in greenbelt for O3. The concentrations of air pollutants, except for O3, were generally higher in big cities during weekdays, while O3 showed its peak in suburban areas or small cities during weekends. The weekly cycle and trends of O3 were significantly out of phase with those of NO2, particularly in the residential and commercial areas, suggesting that vehicle emission was a major source in those areas. The ratios of VOCs to NO2 for each of the land-use types were in the order of I (10.2) > C (8.7) > G (3.9) > R (3.6), suggesting that most areas in South Korea were likely to be VOC-limited for ozone chemistry. The pollutants (NO2, SO2, CO, and PMPM10 except for O3 have decreased, most likely due to the effective government control. The total oxidant values (OX = O3 + NO2) with the land-use types were analyzed for the local and regional (or background) contributions of O3, respectively, and the order of OX (ppb) was C (57

  7. The Fort Collins Commuter Study: Impact of route type and transport mode on personal exposure to multiple air pollutants

    PubMed Central

    Good, Nicholas; Mölter, Anna; Ackerson, Charis; Bachand, Annette; Carpenter, Taylor; Clark, Maggie L; Fedak, Kristen M; Kayne, Ashleigh; Koehler, Kirsten; Moore, Brianna; L'Orange, Christian; Quinn, Casey; Ugave, Viney; Stuart, Amy L; Peel, Jennifer L; Volckens, John

    2016-01-01

    Traffic-related air pollution is associated with increased mortality and morbidity, yet few studies have examined strategies to reduce individual exposure while commuting. The present study aimed to quantify how choice of mode and route type affects personal exposure to air pollutants during commuting. We analyzed within-person difference in exposures to multiple air pollutants (black carbon (BC), carbon monoxide (CO), ultrafine particle number concentration (PNC), and fine particulate matter (PM2.5)) during commutes between the home and workplace for 45 participants. Participants completed 8 days of commuting by car and bicycle on direct and alternative (reduced traffic) routes. Mean within-person exposures to BC, PM2.5, and PNC were higher when commuting by cycling than when driving, but mean CO exposure was lower when cycling. Exposures to CO and BC were reduced when commuting along alternative routes. When cumulative exposure was considered, the benefits from cycling were attenuated, in the case of CO, or exacerbated, in the case of particulate exposures, owing to the increased duration of the commute. Although choice of route can reduce mean exposure, the effect of route length and duration often offsets these reductions when cumulative exposure is considered. Furthermore, increased ventilation rate when cycling may result in a more harmful dose than inhalation at a lower ventilation rate. PMID:26507004

  8. Lipopolysaccharide-Activated Leukocytes Enhance Thymic Stromal Lymphopoietin Production in a Mouse Air-Pouch-Type Inflammation Model.

    PubMed

    Segawa, Ryosuke; Mizuno, Natsumi; Hatayama, Takahiro; Jiangxu, Dong; Hiratsuka, Masahiro; Endo, Yasuo; Hirasawa, Noriyasu

    2016-08-01

    Thymic stromal lymphopoietin (TSLP) is a key cytokine that exacerbates allergic and fibrotic reactions. Several microbes and virus components have been shown to induce TSLP production, mainly in epithelial cells. TLR4 activators, such as lipopolysaccharide (LPS), induce TSLP production in vivo, although the underlying mechanisms remain unclear. In this study, we investigated the contribution of LPS-activated leukocytes to the production of TSLP in a mouse air-pouch-type inflammation model. LPS induced the production of TSLP in this model but not in the mouse keratinocyte cell line PAM212. Transfer of the infiltrated leukocytes collected from an LPS-injected air pouch to the air pouch of another mouse enhanced TSLP production. Further, the LPS-activated leukocytes produced tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β); a deficiency in these cytokines attenuated the LPS-induced production of TSLP. TSLP production was induced by TNF-α and enhanced by IL-1β and LPS in the PAM212 cells. These results demonstrated that TNF-α and IL-1β, which are partly produced by LPS-activated leukocytes, contribute to TSLP production via TLR4 activation in vivo. PMID:27271511

  9. The Fort Collins Commuter Study: Impact of route type and transport mode on personal exposure to multiple air pollutants.

    PubMed

    Good, Nicholas; Mölter, Anna; Ackerson, Charis; Bachand, Annette; Carpenter, Taylor; Clark, Maggie L; Fedak, Kristen M; Kayne, Ashleigh; Koehler, Kirsten; Moore, Brianna; L'Orange, Christian; Quinn, Casey; Ugave, Viney; Stuart, Amy L; Peel, Jennifer L; Volckens, John

    2016-06-01

    Traffic-related air pollution is associated with increased mortality and morbidity, yet few studies have examined strategies to reduce individual exposure while commuting. The present study aimed to quantify how choice of mode and route type affects personal exposure to air pollutants during commuting. We analyzed within-person difference in exposures to multiple air pollutants (black carbon (BC), carbon monoxide (CO), ultrafine particle number concentration (PNC), and fine particulate matter (PM2.5)) during commutes between the home and workplace for 45 participants. Participants completed 8 days of commuting by car and bicycle on direct and alternative (reduced traffic) routes. Mean within-person exposures to BC, PM2.5, and PNC were higher when commuting by cycling than when driving, but mean CO exposure was lower when cycling. Exposures to CO and BC were reduced when commuting along alternative routes. When cumulative exposure was considered, the benefits from cycling were attenuated, in the case of CO, or exacerbated, in the case of particulate exposures, owing to the increased duration of the commute. Although choice of route can reduce mean exposure, the effect of route length and duration often offsets these reductions when cumulative exposure is considered. Furthermore, increased ventilation rate when cycling may result in a more harmful dose than inhalation at a lower ventilation rate. PMID:26507004

  10. Introduction Analysis of Refrigerating and Air-Conditioning Technologies in Micro Grid Type Food Industrial Park

    NASA Astrophysics Data System (ADS)

    Shimazaki, Yoichi

    The aim of this study was to evaluate the refrigerating and air-conditioning technologies in cases of introducing both cogeneration system and energy network in food industrial park. The energy data of 14 factories were classified into steam, hot water, heating, cooling, refrigerating, freezing and electric power by interviews. The author developed a micro grid model based on linear programming so as to minimize the total system costs. The industrial park was divided into the 2,500 square meter mesh in order to take steam transport into consideration. Four cases were investigated. It was found that the electric power driven freezer was introduced compared with the ammonia absorption freezer. The ammonia absorption freezer was introduced in the factory that there is a little steam demand and large freezing demand at the same time.

  11. Steps Toward an EOS-Era Aerosol Air Mass Type Climatology

    NASA Technical Reports Server (NTRS)

    Kahn, Ralph A.

    2012-01-01

    We still have a way to go to develop a global climatology of aerosol type from the EOS-era satellite data record that currently spans more than 12 years of observations. We have demonstrated the ability to retrieve aerosol type regionally, providing a classification based on the combined constraints on particle size, shape, and single-scattering albedo (SSA) from the MISR instrument. Under good but not necessarily ideal conditions, the MISR data can distinguish three-to-five size bins, two-to-four bins in SSA, and spherical vs. non-spherical particles. However, retrieval sensitivity varies enormously with scene conditions. So, for example, there is less information about aerosol type when the mid-visible aerosol optical depth (AOD) is less that about 0.15 or 0.2.

  12. Einstein Observatory magnitude-limited X-ray survey of late-type giant and supergiant stars

    SciTech Connect

    Maggio, A.; Vaiana, G.S.; Haisch, B.M.; Stern, R.A.; Bookbinder, J. Lockheed Research Laboratories, Palo Alto, CA Joint Institute for Laboratory Astrophysics, Boulder, CO Smithsonian Astrophysical Observatory, Cambridge, MA )

    1990-01-01

    Results are presented of an extensive X-ray survey of 380 giant and supergiant stars of spectral types from F to M, carried out with the Einstein Observatory. It was found that the observed F giants or subgiants (slightly evolved stars with a mass M less than about 2 solar masses) are X-ray emitters at the same level of main-sequence stars of similar spectral type. The G giants show a range of emissions more than 3 orders of magnitude wide; some single G giants exist with X-ray luminosities comparable to RS CVn systems, while some nearby large G giants have upper limits on the X-ray emission below typical solar values. The K giants have an observed X-ray emission level significantly lower than F and F giants. None of the 29 M giants were detected, except for one spectroscopic binary. 79 refs.

  13. Limits on spin-independent couplings of WIMP dark matter with a p-type point-contact germanium detector.

    PubMed

    Li, H B; Liao, H Y; Lin, S T; Liu, S K; Singh, L; Singh, M K; Soma, A K; Wong, H T; Wu, Y C; Zhao, W; Asryan, G; Chuang, Y C; Deniz, M; Fang, J M; Hsu, C L; Huang, T R; Kiran Kumar, G; Lee, S C; Li, J; Li, J M; Li, Y J; Li, Y L; Lin, C W; Lin, F K; Liu, Y F; Ma, H; Ruan, X C; Shen, Y T; Singh, V; Tang, C J; Tseng, C H; Xu, Y; Yang, S W; Yu, C X; Yue, Q; Zeng, Z; Zeyrek, M; Zhou, Z Y

    2013-06-28

    We report new limits on a spin-independent weakly interacting massive particle (WIMP)-nucleon interaction cross section using 39.5 kg days of data taken with a p-type point-contact germanium detector of 840 g fiducial mass at the Kuo-Sheng Reactor Neutrino Laboratory. Crucial to this study is the understanding of the selection procedures and, in particular, the bulk-surface events differentiation at the sub-keV range. The signal-retaining and background-rejecting efficiencies were measured with calibration gamma sources and a novel n-type point-contact germanium detector. Part of the parameter space in the cross section versus WIMP-mass implied by various experiments is probed and excluded. PMID:23848861

  14. Einstein Observatory magnitude-limited X-ray survey of late-type giant and supergiant stars

    NASA Technical Reports Server (NTRS)

    Maggio, A.; Vaiana, G. S.; Haisch, B. M.; Stern, R. A.; Bookbinder, J.

    1990-01-01

    Results are presented of an extensive X-ray survey of 380 giant and supergiant stars of spectral types from F to M, carried out with the Einstein Observatory. It was found that the observed F giants or subgiants (slightly evolved stars with a mass M less than about 2 solar masses) are X-ray emitters at the same level of main-sequence stars of similar spectral type. The G giants show a range of emissions more than 3 orders of magnitude wide; some single G giants exist with X-ray luminosities comparable to RS CVn systems, while some nearby large G giants have upper limits on the X-ray emission below typical solar values. The K giants have an observed X-ray emission level significantly lower than F and F giants. None of the 29 M giants were detected, except for one spectroscopic binary.

  15. Use and Limitations of Electron Flood Gun Control of Surface Potential During XPS: Two Non-homogeneous Sample Types

    SciTech Connect

    Baer, Donald R.; Engelhard, Mark H.; Gaspar, Dan J.; Lea, Alan S.; Windisch, Charles F.

    2002-10-01

    The ability of charge compensation methods to control the surface potentials for two types of non-homogenous samples is examined. Results demonstrate that two newer types of charge compensation systems have improved performance in relation to some previous flood gun methods and reaffirm the concept that a primary objective of charge compensation is to find conditions for which the surface potential of the specimen is as uniform as possible. However, experiments involving both flood gun use and specimen grounding, demonstrate that peak broadening and shifting can occur when two (or more) potentials are present in the region of analysis. Finally, the ability of interface charge to shift specimen potentials and measured binding energies demonstrates fundamental limitations to the absolute accuracy of binding energy measurements, but also remind us that charging phenomena can be used to obtain important information about the sample.

  16. AIR12, a b-type cytochrome of the plasma membrane of Arabidopsis thaliana is a negative regulator of resistance against Botrytis cinerea.

    PubMed

    Costa, Alex; Barbaro, Maria Raffaella; Sicilia, Francesca; Preger, Valeria; Krieger-Liszkay, Anja; Sparla, Francesca; De Lorenzo, Giulia; Trost, Paolo

    2015-04-01

    AIR12 (Auxin Induced in Root culture) is a single gene of Arabidopsis that codes for a mono-heme cytochrome b. Recombinant AIR12 from Arabidopsis accepted electrons from ascorbate or superoxide, and donated electrons to either monodehydroascorbate or oxygen. AIR12 was found associated in vivo to the plasma membrane. Though linked to the membrane by a glycophosphatidylinositol anchor, AIR12 is a hydrophilic and glycosylated protein predicted to be fully exposed to the apoplast. The expression pattern of AIR12 in Arabidopsis is developmentally regulated and correlated to sites of controlled cell separation (e.g. micropilar endosperm during germination, epidermal cells surrounding the emerging lateral root) and cells around wounds. Arabidopsis (Landsberg erecta-0) mutants with altered levels of AIR12 did not show any obvious phenotype. However, AIR12-overexpressing plants accumulated ROS (superoxide, hydrogen peroxide) and lipid peroxides in leaves, indicating that AIR12 may alter the redox state of the apoplast under particular conditions. On the other hand, AIR12-knock out plants displayed a strongly decreased susceptibility to Botrytis cinerea infection, which in turn induced AIR12 expression in susceptible wild type plants. Altogether, the results suggest that AIR12 plays a role in the regulation of the apoplastic redox state and in the response to necrotrophic pathogens. Possible relationships between these functions are discussed. PMID:25711811

  17. The effect of incomplete fuel-air mixing on the lean limit and emissions characteristics of a Lean Prevaporized Premixed (LPP) combustor

    NASA Technical Reports Server (NTRS)

    Santavicca, D. A.; Steinberger, R. L.; Gibbons, K. A.; Citeno, J. V.; Mills, S.

    1993-01-01

    Results are presented from an experimental study of the effect of incomplete fuel-air mixing on the lean limit and emissions characteristics of a lean, prevaporized, premixed (LPP), coaxial mixing tube combustor. Two-dimensional exciplex fluorescence was used to characterize the degree of fuel vaporization and mixing at the combustor inlet under non-combusting conditions. These tests were conducted at a pressure of 4 atm., a temperature of 400 C, a mixer tube velocity of 100 m/sec and an equivalence ratio of .8, using a mixture of tetradecane, 1 methyl naphthalene and TMPD as a fuel simulant. Fuel-air mixtures with two distinct spatial distributions were studied. The exciplex measurements showed that there was a significant amount of unvaporized fuel at the combustor entrance in both cases. One case, however, exhibited a very non-uniform distribution of fuel liquid and vapor at the combustor entrance, i.e., with most of the fuel in the upper half of the combustor tube, while in the other case, both the fuel liquid and vapor were much more uniformly distributed across the width of the combustor entrance. The lean limit and emissions measurements were all made at a pressure of 4 atm. and a mixer tube velocity of 100 m/sec, using Jet A fuel and both fuel-air mixture distributions. Contrary to what was expected, the better mixed case was found to have a substantially leaner operating limit. The two mixture distributions also unexpectedly resulted in comparable NO(x) emissions, for a given equivalence ratio and inlet temperature, however, lower NO(x) emissions were possible in the better mixed case due to its leaner operating limit.

  18. Dependence of air masses type on PBL vertical structure retrieved at the Mace Head station during EUCAARI campaign.

    NASA Astrophysics Data System (ADS)

    Milroy, Conor; Martucci, Giovanni; O'Dowd, Colin

    2010-05-01

    During the EUCAARI Intensive Observing Period held at the Mace Head GAW station from mid-May to mid-June, 2008, the PBL depth has been continuously measured by two ceilometers (Vaisala CL31 and Jenoptik CHM15K) and a microwave radiometer (RPG-HATPRO). The Lidar-Ceilometer, through the gradients in aerosol backscatter profiles, and the microwave profiler, through gradients in the specific humidity profiles, were used to remotely-sense the boundary layer structure. An automatic, newly developed Temporal Height-Tracking (THT) algorithm (Martucci et al., 2010) have been applied to both type of instruments data to retrieve the 2-layered structure of the local marine boundary layer. The two layers are defined as a lower, well mixed layer, i.e. the surface mixed layer, and the layer occupying the region below the free Troposphere inversion, i.e. the decoupled residual or convective layer. A categorization of the incoming air masses has been performed based on their origins and been used to asses the correlation with the PBL depths. The study confirmed the dependence of PBL vertical structure on different air masses and different type of advected aerosol.

  19. Experimental Study on Branch and Diffuse Type of Streamers in Leader Restrike of Long Air Gap Discharge

    NASA Astrophysics Data System (ADS)

    Chen, She; Zeng, Rong; Zhuang, Chijie; Zhou, Xuan; Ding, Yujian

    2016-03-01

    One of the main problems in the Ultra High Voltage (UHV) transmission project is to choose the external insulation distance, which requires a deep understanding of the long air gap discharge mechanism. The leader-streamer propagation is one of most important stages in long air gap discharge. In the conductor-tower lattice configuration, we have measured the voltage, the current on the high voltage side and the electric field in the gap. While the streamer in the leader-streamer system presented a conical or hyperboloid diffuse shape, the clear branch structure streamer in front of the leader was firstly observed by a high speed camera in the experiment. Besides, it is found that the leader velocity, width and injected charge for the branch type streamer are greater than those of a diffuse type. We propose that the phenomenon results from the high humidity, which was 15.5-16.5 g/m3 in our experiment. supported by the Fund of the National Priority Basic Research of China (2011CB209403) and National Natural Science Foundation of China (Nos. 51325703, 51377094, 51577098)

  20. AIR QUALITY AND HEN HEALTH STATUS IN THREE TYPES OF COMMERCIAL LAYING HEN HOUSES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this field observational study, three types of laying-hen houses, i.e., high-rise (HR), manure-belt (MB), and cage-free floor-raised (FR), were monitored for environmental temperature, relative humidity, carbon dioxide (CO2), and atmospheric ammonia (NH3) during winter and summer conditions in Io...

  1. High Cooling Rates of Type-II Chondrules: Limited Overgrowths on Phenocrysts Following the Final Melting Event

    NASA Technical Reports Server (NTRS)

    Wasson, John T.; Rubin, Alan E.

    2003-01-01

    In a study of type-II chondrules in Y81020 Wasson and Rubin (2003) described three kinds of evidence indicating that only minor (4-10 m) olivine growth occurred following the final melting event: 1) Nearly all (>90%) type-II chondrules in CO3.0 chondrites contain low-FeO relict grains; overgrowths on these relicts are narrow, in the range of 2-12 m. 2) Most type-II chondrules contain small (10-20 m) FeO-rich olivine grains with decurved surfaces and acute angles between faces indicating that the grains are fragments from an earlier generation of chondrules; the limited overgrowth thicknesses following the last melting event are too thin to disguise the shard-like nature of these small grains. 3) Most type-II chondrules contain many small (<20 m) euhedral or subhedral phenocrysts with central compositions that are much more ferroan than the centers of the large phenocrysts; their small sizes document the small amount of growth that occurred following the final melting event.We have additional data on chondrules in Y81020 and Semarkona, and we have reinterpreted observations of Jones (1990). The striking feature of this chondrule is the large number of tiny fragments. The chondrule precursor initially consisted of crushed olivine.

  2. Type III secretion system expression in oxygen-limited Pseudomonas aeruginosa cultures is stimulated by isocitrate lyase activity

    PubMed Central

    Chung, Jade C. S.; Rzhepishevska, Olena; Ramstedt, Madeleine; Welch, Martin

    2013-01-01

    Pseudomonas aeruginosa is an opportunistic human pathogen and a common cause of chronic infections in individuals with cystic fibrosis (CF). Oxygen limitation was recently reported to regulate the expression of a major virulence determinant in P. aeruginosa, the type III secretion system (T3SS). Here, we show that expression of the T3SS in oxygen-limited growth conditions is strongly dependent on the glyoxylate shunt enzyme, isocitrate lyase (ICL; encoded by aceA), which was previously shown to be highly expressed in CF isolates. ICL-dependent regulation of the T3SS did not alter the expression level of the master transcriptional regulator, ExsA, but did affect expression of the T3 structural proteins, effectors and regulators (ExsC, ExsD and ExsE). An aceA mutant displayed enhanced biofilm formation during anaerobic growth, which suggested that AceA-dependent modulation of type III secretion might impinge upon the RetS/LadS signalling pathways. Indeed, our data suggest that RetS is able to mediate some of its effects through AceA, as expression of aceA in trans partially restored T3SS expression in a retS mutant. Our findings indicate that AceA is a key player in the metabolic regulation of T3SS expression during oxygen-limited growth of P. aeruginosa. To the best of our knowledge, this is the first demonstration that the T3SS can be regulated by factors that do not affect ExsA expression levels. PMID:23363478

  3. Definition of Small Gram Quantity Contents for Type B Radioactive Material Transportation Packages: Activity-Based Content Limitations

    SciTech Connect

    Sitaraman, S; Kim, S; Biswas, D; Hafner, R; Anderson, B

    2010-10-27

    Since the 1960's, the Department of Transportation Specification (DOT Spec) 6M packages have been used extensively for transportation of Type B quantities of radioactive materials between Department of Energy (DOE) facilities, laboratories, and productions sites. However, due to the advancement of packaging technology, the aging of the 6M packages, and variability in the quality of the packages, the DOT implemented a phased elimination of the 6M specification packages (and other DOT Spec packages) in favor of packages certified to meet federal performance requirements. DOT issued the final rule in the Federal Register on October 1, 2004 requiring that use of the DOT Specification 6M be discontinued as of October 1, 2008. A main driver for the change was the fact that the 6M specification packagings were not supported by a Safety Analysis Report for Packaging (SARP) that was compliant with Title 10 of the Code of Federal Regulations part 71 (10 CFR 71). Therefore, materials that would have historically been shipped in 6M packages are being identified as contents in Type B (and sometimes Type A fissile) package applications and addenda that are to be certified under the requirements of 10 CFR 71. The requirements in 10 CFR 71 include that the Safety Analysis Report for Packaging (SARP) must identify the maximum radioactivity of radioactive constituents and maximum quantities of fissile constituents (10 CFR 71.33(b)(1) and 10 CFR 71.33(b)(2)), and that the application (i.e., SARP submittal or SARP addendum) demonstrates that the external dose rate (due to the maximum radioactivity of radioactive constituents and maximum quantities of fissile constituents) on the surface of the packaging (i.e., package and contents) not exceed 200 mrem/hr (10 CFR 71.35(a), 10 CFR 71.47(a)). It has been proposed that a 'Small Gram Quantity' of radioactive material be defined, such that, when loaded in a transportation package, the dose rates at external points of an unshielded packaging

  4. Magnetically insulated coaxial vacuum diode with partial space-charge-limited explosive emission from edge-type cathode

    NASA Astrophysics Data System (ADS)

    Belomyttsev, S. Ya.; Rostov, V. V.; Romanchenko, I. V.; Shunailov, S. A.; Kolomiets, M. D.; Mesyats, G. A.; Sharypov, K. A.; Shpak, V. G.; Ulmaskulov, M. R.; Yalandin, M. I.

    2016-01-01

    The vacuum current associated with any type of electron emission for arbitrary configuration of the diode depends on the combination of the applied electric field and vacuum space charge (VSC) field created by the current. Such fundamental statement should give very close links between the diode current and the normalized cathode field θ which has been introduced by Forbes in 2008 for planar diodes as a reduction in the cathode surface field: θ = field-with/field-without VSC. This article reports the universal approximation of the type of cos(πθ/2) that is the ratio of the actual current and the fully space-charge-limited current. Also, the theoretical treatment and the experimental method of determination of the dynamic emissive characteristics of the macroscopic explosive emission from edge-type cathodes in the coaxial diode are developed. The experimental results obtained with a picosecond time reference between the cathode voltage and the onset of the high-current electron beam exhibit a good coincidence with the theoretical predictions. The presented methods enable the analysis of a real-time-resolved dynamics associated with the dense, magnetized electron beam formation, acceleration and drift motion, including kinematic effects and the phase-stable excitation of high-power microwave oscillators.

  5. SCC Propagation Rate of Type 304, 304L Steels Under Oceanic Air Environment

    SciTech Connect

    Akio Kosaki

    2006-07-01

    Corrosion integrity of canister in the concrete cask for spent fuel storage is very important because the canister serves to maintain the sealability over the storage period of 40 to 60 years. Natural exposure and accelerated corrosion tests of conventional stainless steels for canister, that are Type 304, 304L, and 316(LN), for concrete cask's canister have been conducted by using many three Point Bending (3PB) test specimens and compared. The SCC propagation rates in Type 304 and 304L at the natural condition were about 1.2 E-12 to 1.8 E-11 m/s at the K (Stress Intensity Factor) range of 0.6 to 9.0 MPa/m, and that of the accelerate test (60 degrees C, 95%RHS., filled with NaCl mist.) were about 1.0 E-10 to 3.5 E-9 m/s at the K range of 0.3 to 32 MPa/m. The SCC propagation rates under both natural and accelerated conditions were independent with K. Both da/dt values of the direct exposure test and of the under glass exposure test were in the same scattering band. (author)

  6. Design for H type co-planar precision stage based on closed air bearing guideway with vacuum attraction force

    NASA Astrophysics Data System (ADS)

    Zhang, Bin; Shi, Zhaoyao; Lin, Jiachun; Zhang, Hua

    2011-12-01

    The accuracy of traditional two-dimensional precision stage is limited not only by the accuracy of each guideway but also by the configuration of the stage. It is not easy to calculate and compensate the total accuracy of the stage due to the complicated influence caused by the different position of the slides. An air bearing guideways with vacuum attraction forces has been designed with closed slide structure to enhance the stiffness and avoid the deformation caused by the weight of slide and workpieces. An H style two-dimension ultra-precision stage with co-planar structure has been developed based on the air bearing guideways to avoid the multi-influence by the axes. Driven by linear motors, the position of the workpiece is encoded by length scales with resolution of 50nm and thermal expansion of 0.6 μm/m/°C (0 °C to 30 °C). The travel span of the stage is 320x320mm, during which each axis has a positioning accuracy of +/-1μm, a repeatability of +/-0.3μm and a straightness of +/-0.5μm. The stage can be applied in precision manufacturing and measurement.

  7. Burning Velocity Measurements in Aluminum-Air Suspensions using Bunsen Type Dust Flames

    NASA Technical Reports Server (NTRS)

    Lee, John; Goroshin, Samuel; Kolbe, Massimiliano

    2001-01-01

    Laminar burning velocity (sometimes also referred in literature as fundamental or normal flame propagation speed) is probably the most important combustion characteristic of the premixed combustible mixture. The majority of experimental data on burning velocities in gaseous mixtures was obtained with the help of the Bunsen conical flame. The Bunsen cone method was found to be sufficiently accurate for gaseous mixtures with burning velocities higher than 10-15 cm/s at normal pressure. Hans Cassel was the first to demonstrate that suspensions of micron-size solid fuel particles in a gaseous oxidizer can also form self-sustained Bunsen flames. He was able to stabilize Bunsen flames in a number of suspensions of different nonvolatile solid fuels (aluminum, carbon, and boron). Using the Bunsen cone method he estimated burning velocities in the premixed aluminum-air mixtures (particle size less than 10 microns) to be in the range of 30-40 cm/s. Cassel also found, that the burning velocity in dust clouds is a function of the burner diameter. In our recent work, we have used the Bunsen cone method to investigate dependence of burning velocity on dust concentration in fuel-rich aluminum dust clouds. Burning velocities in stoichiometric and fuel-rich aluminum dust suspensions with average particle sizes of about 5 microns were found to be in the range of 20-25 cm/s and largely independent on dust concentration. These results raise the question to what degree burning velocities derived from Bunsen flame specifically and other dust flame configurations in general, are indeed fundamental characteristics of the mixture and to what degree are they apparatus dependent. Dust flames in comparison to gas combustion, are thicker, may be influenced by radiation heat transfer in the flame front, respond differently to heat losses, and are fundamentally influenced by the particular flow configuration due to the particles inertia. Since characteristic spatial scales of dust flames are

  8. A catheter-type flow sensor for measurement of aspirated- and inspired-air characteristics in the bronchial region

    NASA Astrophysics Data System (ADS)

    Shikida, M.; Naito, J.; Yokota, T.; Kawabe, T.; Hayashi, Y.; Sato, K.

    2009-10-01

    We developed a novel catheter-type flow sensor for measuring the aspirated- and inspired-air characteristics trans-bronchially. An on-wall in-tube thermal flow sensor is mounted inside the tube, and it is used as a measurement tool in a bronchoscope. The external diameter of the tube is less than a few mm, and therefore, it can evaluate the flow characteristics in the small bronchial region. We newly developed a fabrication process to miniaturize it to less than 2.0 mm in the external diameter by using a heat shrinkable tube. A film sensor fabricated by photolithography was inserted into the tube by hand. By applying a heat shrinking process, the film was automatically mounted on the inner wall surface, and the outer size of the tube was miniaturized to almost half its original size. The final inner and outer diameters of the tube were 1.0 mm and 1.8 mm, respectively. The relationship between the input power of the sensor and the flow rate obeyed King's equation in both forward and reverse flow conditions. The sensor output dependence on ambient temperature was also studied, and the curve obtained at 39.2 °C was used as the calibration curve in animal experiments. The sensor characteristics under reciprocating flow were studied by using a ventilator, and we confirmed that the sensor was able to measure the reciprocating flow at 2.0 Hz. Finally, we successfully measured the aspirated- and inspired-air characteristics in the air passage of a rat.

  9. An upper limit of muon flux of energies above 100 TeV determined from horizontal air showers observed at Akeno

    NASA Technical Reports Server (NTRS)

    Nagano, M.; Yoshii, H.; Hara, T.; Kamata, K.; Kawaguchi, S.; Kifune, T.

    1985-01-01

    Muon energy spectrum above 100 TeV was determined by observing the extensive air showers (EAS) from the horizontal direction (HAS). No definite muon originated shower of sizes above 100,000 and zenith angles above 60 deg was observed. The upper limits of HAS intensity is 5x10/12 m/2 s/1 sn/1 above 100,000. It is indicated that the upper limit of muon flux above 100 TeV is about 1.3x10/8 m/2 s/1 sr/1 and is in agreement with that expected from the primary spectrum with a knee assuming scaling in the fragmentation region and 40% protons in the primary beam. The critical energy at which muon flux from prompt processes take over that from the conventional process is higher than 100 Tev at horizontal direction.

  10. External stress-corrosion cracking of a 1.22-m-diameter type 316 stainless steel air valve

    NASA Technical Reports Server (NTRS)

    Moore, Thomas J.; Telesman, Jack; Moore, Allan S.; Johnson, Dereck F.; Kuivinen, David E.

    1993-01-01

    An investigation was conducted to determine the cause of the failure of a massive AISI Type 316 stainless steel valve which controlled combustion air to a jet engine test facility. Several through-the-wall cracks were present near welded joints in the valve skirt. The valve had been in outdoor service for 18 years. Samples were taken in the cracked regions for metallographic and chemical analyses. Insulating material and sources of water mist in the vicinity of the failed valve were analyzed for chlorides. A scanning electron microscope was used to determine whether foreign elements were present in a crack. On the basis of the information generated, the failure was characterized as external stress-corrosion cracking. The cracking resulted from a combination of residual tensile stress from welding and the presence of aqueous chlorides. Recommended countermeasures are included.

  11. Molecular typing for fungi--a critical review of the possibilities and limitations of currently and future methods.

    PubMed

    Gil-Lamaignere, C; Roilides, E; Hacker, J; Müller, F-M C

    2003-03-01

    Invasive fungal infections represent an increasing problem in patients with inherited and acquired immunodeficiencies. Molecular biotyping techniques, such as DNA fingerprinting, are useful tools to increase our knowledge of the pathogenic organisms that cause them, and thus to improve their treatment and develop prevention strategies. In the present review, we evaluate and discuss the possibilities and limitations of the methods currently used for biotyping strains of fungal species. These include techniques based on restriction fragment length polymorphism (RFLP) with or without hybridization to probes (Southern), PCR-based techniques, electrophoretic karyotyping (EK), and multilocus enzyme electrophoresis (MLEE). Additionally, we discuss newer techniques that are being developed for the fingerprinting of fungal strains. Among them, we review conformation-based polymorphism scanning methods, such as single-strand conformation polymorphism analysis (SSCP) and heteroduplex mobility assays, sequencing strategies such as multilocus sequence typing (MLST) and DNA microarrays. PMID:12667249

  12. Experimental study of the types of cavitation by air seeding using light microscopy.

    PubMed

    Shen, Fanyi; Cheng, Yanxia; Zhang, Li; Gao, Rongfu; Shao, Xuemeng

    2015-12-01

    Recently, three types of cavitation: (i) expanding gradually; (ii) expanding-exploding, becoming a long-shaped bubble-lengthening by degrees; (iii) suddenly exploding and fully filling the conduit instantly, were proposed. Directed by this theory, experiments were performed using light microscopy to study the natural drying processes of xylem sections of Platycladus orientalis (L.) Franco. Three different phenomena of gas filling process in conduits were captured by replaying recorded videos. The first phenomenon is that a bubble emerging in a conduit expands and elongates gradually to fill the conduit. The second phenomenon is that a bubble emerging in a conduit expands gradually, and then suddenly becomes long-shaped, and extends continuously. The third phenomenon is that a bubble instantly fully fills a conduit. This paper suggests in these experiments that after losing the bulk water of a section, as the water stress of that section became more severe, the water pressures of different conduits of the section were not necessarily the same, and as time went on, the water pressures decreased constantly. Considering some practical factors, the three phenomena captured in our experiment are explained by our theory. PMID:26338303

  13. Effect of air temperature on forecasting the start of Cupressaceae pollen type in Ponferrada (Leon, Spain).

    PubMed

    Fuertes-Rodríguez, Carmen Reyes; González-Parrado, Zulima; Vega-Maray, Ana María; Valencia-Barrera, Rosa María; Fernández-González, Delia

    2007-01-01

    In order to survive periods of adverse cold climatic conditions, plant requirements are satisfied by means of physiological adaptations to prevent cells from freezing. Thus, the growth of woody plants in temperate regions slows down and they enter into a physiological state called dormancy. In order to identify the chilling and heat requirements to overcome the dormancy period of Cupressaceae pollen type in the south of Europe, we have carried out our study with aerobiological data from a 10-year (1996-2005) period in Ponferrada, León (Spain). For the chilling requirements the best result was with a threshold temperature of 7.1 degrees C and an average of 927 CH. Calculation of heat requirements was carried out with maximum temperature, with 490 growth degree days (GDD) needed, with a threshold temperature of 0 degrees C. We have used the 2002-2003, 2003-2004 and 2004-2005 periods in order to determine the real validity of the model. We have not used these years in developing the models. The dates predicted differ in only a few days from those observed: in 2002-2003 there was a difference of 11 days, in 2003-2004 predicted and observed dates were the same, but in 2004-2005 the difference obtained was of 43 days. PMID:18247458

  14. Enhanced anthocyanin production from grape callus in an air-lift type bioreactor using a viscous additive-supplemented medium.

    PubMed

    Honda, Hiroyuki; Hiraoka, Kousuke; Nagamori, Eiji; Omote, Mariko; Kato, Yoshihito; Hiraoka, Setsuro; Kobayashi, Takeshi

    2002-01-01

    An N-medium containing carboxymethyl cellulose (CMC) was applied to an air-lift type bioreactor culture of grape (Vitis vinifera cv. Bailey alicant A.) callus, and anthocyanin production was investigated. Grape callus grew well at an air flow rate of 80 ml/min and anthocyanin production was significantly increased in the N-medium, reaching 17 mg/l after 7 d of culture. The anthocyanin content of the N-medium was about two times higher than that of the conventional medium without CMC. The effect of air flow rate was also investigated within the range from 40 to 160 ml/min. A twofold increase in anthocyanin content was obtained at all the air flow rates tested in the N-medium. The distribution of grape callus size obtained after 7 d of the bioreactor culture was investigated. The average callus size was 490 mum which was 1.6 times larger than that obtained in the conventional medium. It was found that large calli with a relatively high anthocyanin pigment content were formed in the bioreactor culture using the N-medium. The fluid dynamics in the bioreactor was also investigated at three points (top, middle and bottom) in the bioreactor by laser doppler velocimetry. The average axial velocity of the circulated medium was 0.4 times lower than that of the conventional medium while their average radial velocities were almost the same (zero). The standard deviation of radial velocity fluctuation in the N-medium was also 0.4 times less than that in the conventional medium. These results suggest that turbulent flow occurred in the bioreactor culture using the conventional medium and the degree of turbulent flow decreased significantly when 0.8% CMC was added to the medium to prepare the N-medium. A change of the flow pattern is considered to be the cause of the decrease in hydrodynamic stress, resulting in enhanced pigment production due to the enlargement of the callus. PMID:16233283

  15. Air pollution and blood lipid markers levels: Estimating short and long-term effects on elderly hypertension inpatients complicated with or without type 2 diabetes.

    PubMed

    Xiao, Sanhua; Liu, Ranran; Wei, Youxiu; Feng, Lin; Lv, Xuemin; Tang, Fei

    2016-08-01

    With the development of society and the economy, many Chinese cities are shrouded in pollution haze for much of the year. Scientific studies have identified various adverse effects of air pollutants on human beings. However, the relationships between air pollution and blood lipid levels are still unclear. The objective of this study is to explore the short and long-term effects of air pollution on eight blood lipid markers among elderly hypertension inpatients complicated with or without type 2 diabetes (T2D). Blood lipid markers which met the pre-established inclusion criteria were exported from the medical record system. Air pollution data were acquired from the official environmental protection website. Associations between the air quality index and the blood lipid indexes were analyzed by one-way ANOVA and further Bonferroni correction. In an exposure time of 7 days or longer, blood lipid markers were somewhat affected by poor air quality. However, the results could not predict whether atherosclerosis would be promoted or inhibited by poorer air condition. Changes of blood lipid markers of hypertension inpatients with or without T2D were not completely the same, but no blood lipid markers had an opposite trend between the two populations. The air quality index was associated with changes to blood lipid markers to some extent in a population of hypertension inpatients with or without T2D. Further studies are needed to investigate the potential mechanism by which air pollutants induce blood lipids changes. PMID:27180144

  16. Patterns and Limitations of Urban Human Mobility Resilience under the Influence of Multiple Types of Natural Disaster

    PubMed Central

    Wang, Qi; Taylor, John E.

    2016-01-01

    Natural disasters pose serious threats to large urban areas, therefore understanding and predicting human movements is critical for evaluating a population’s vulnerability and resilience and developing plans for disaster evacuation, response and relief. However, only limited research has been conducted into the effect of natural disasters on human mobility. This study examines how natural disasters influence human mobility patterns in urban populations using individuals’ movement data collected from Twitter. We selected fifteen destructive cases across five types of natural disaster and analyzed the human movement data before, during, and after each event, comparing the perturbed and steady state movement data. The results suggest that the power-law can describe human mobility in most cases and that human mobility patterns observed in steady states are often correlated with those in perturbed states, highlighting their inherent resilience. However, the quantitative analysis shows that this resilience has its limits and can fail in more powerful natural disasters. The findings from this study will deepen our understanding of the interaction between urban dwellers and civil infrastructure, improve our ability to predict human movement patterns during natural disasters, and facilitate contingency planning by policymakers. PMID:26820404

  17. Experimental two-phase flow measurement using ultra fast limited-angle-type electron beam X-ray computed tomography

    NASA Astrophysics Data System (ADS)

    Bieberle, M.; Fischer, F.; Schleicher, E.; Koch, D.; Menz, H.-J.; Mayer, H.-G.; Hampel, U.

    2009-09-01

    An experimental evaluation of a novel limited-angle-type ultra fast electron beam X-ray computed tomography approach for the visualization and measurement of a gas-liquid two-phase flow is reported here. With this method, a simple linear electron beam scan is used to produce instantaneous radiographic views of a two-phase flow in a pipe segment of a flow loop. Electron beam scanning can be performed very rapidly, thus a frame rate of 5 kHz is achieved. Radiographic projections are recorded by a very fast detector arc made of zink-cadmium-telluride elements. This detector records the X-ray radiation passing through the object with a sampling rate of 1 MHz. The reconstruction of slice images from the recorded detector data is a limited-angle problem since in our scanning geometry the object’s Radon space is only incompletely sampled. It was investigated here, whether this technology is able to produce accurate gas fraction data from bubbly two-phase flow. Experiments were performed both on a Perspex phantom with known geometry and an experimental flow loop operated under vacuum conditions in an electron beam processing box.

  18. Application of a modified flux-coupling type superconducting fault current limiter to transient performance enhancement of micro-grid

    NASA Astrophysics Data System (ADS)

    Chen, Lei; Zheng, Feng; Deng, Changhong; Li, Shichun; Li, Miao; Liu, Hui; Zhu, Lin; Guo, Fang

    2015-11-01

    Concerning the application and development of a micro-grid system which is designed to accommodate high penetration of intermittent renewable resources, one of the main issues is related to an increase in the fault-current level. It is crucial to ensure the micro-grid's operational stability and service reliability when a fault occurs in the main network. In this paper, our research group suggests a modified flux-coupling type superconducting fault current limiter (SFCL) to enhance the transient performance of a typical micro-grid system. The SFCL is installed at the point of common coupling (PCC) between the main network and the micro-grid, and it is expected to actively improve the micro-grid's fault ride-through capability. And for some specific faults, the micro-grid should disconnect from the main network, and the SFCL's contribution is to make the micro-grid carry out a smooth transition between its grid-connected and islanded modes. Related theory derivation, technical discussion and simulation analysis are performed. From the demonstrated results, applying the SFCL can effectively limit the fault current, maintain the power balance, and enhance the voltage and frequency stability of the micro-grid.

  19. Analysis of MUSIC-type imaging functional for single, thin electromagnetic inhomogeneity in limited-view inverse scattering problem

    NASA Astrophysics Data System (ADS)

    Ahn, Chi Young; Jeon, Kiwan; Park, Won-Kwang

    2015-06-01

    This study analyzes the well-known MUltiple SIgnal Classification (MUSIC) algorithm to identify unknown support of thin penetrable electromagnetic inhomogeneity from scattered field data collected within the so-called multi-static response matrix in limited-view inverse scattering problems. The mathematical theories of MUSIC are partially discovered, e.g., in the full-view problem, for an unknown target of dielectric contrast or a perfectly conducting crack with the Dirichlet boundary condition (Transverse Magnetic-TM polarization) and so on. Hence, we perform further research to analyze the MUSIC-type imaging functional and to certify some well-known but theoretically unexplained phenomena. For this purpose, we establish a relationship between the MUSIC imaging functional and an infinite series of Bessel functions of integer order of the first kind. This relationship is based on the rigorous asymptotic expansion formula in the existence of a thin inhomogeneity with a smooth supporting curve. Various results of numerical simulation are presented in order to support the identified structure of MUSIC. Although a priori information of the target is needed, we suggest a least condition of range of incident and observation directions to apply MUSIC in the limited-view problem.

  20. Rigorous Derivation of Nonlinear Scalar Conservation Laws from Follow-the-Leader Type Models via Many Particle Limit

    NASA Astrophysics Data System (ADS)

    Di Francesco, M.; Rosini, M. D.

    2015-09-01

    We prove that the unique entropy solution to a scalar nonlinear conservation law with strictly monotone velocity and nonnegative initial condition can be rigorously obtained as the large particle limit of a microscopic follow-the-leader type model, which is interpreted as the discrete Lagrangian approximation of the nonlinear scalar conservation law. More precisely, we prove that the empirical measure (respectively the discretised density) obtained from the follow-the-leader system converges in the 1-Wasserstein topology (respectively in ) to the unique Kružkov entropy solution of the conservation law. The initial data are taken in , nonnegative, and with compact support, hence we are able to handle densities with a vacuum. Our result holds for a reasonably general class of velocity maps (including all the relevant examples in the applications, for example in the Lighthill-Whitham-Richards model for traffic flow) with a possible degenerate slope near the vacuum state. The proof of the result is based on discrete estimates and on a discrete version of the one-sided Oleinik-type condition. In particular, we prove that the regularizing effect for nonlinear scalar conservation laws is intrinsic to the discrete model.

  1. Application of calcium chloride as an additive for secondary refrigerant in the air conditioning system type chiller to minimized energy consumption

    NASA Astrophysics Data System (ADS)

    Suwono, A.; Indartono, Y. S.; Irsyad, M.; Al-Afkar, I. C.

    2015-09-01

    One way to resolve the energy problem is to increase the efficiency of energy use. Air conditioning system is one of the equipment that needs to be considered, because it is the biggest energy user in commercial building sector. Research currently developing is the use of phase change materials (PCM) as thermal energy storage (TES) in the air conditioning system to reduce energy consumption. Salt hydrates have been great potential to be developed because they have been high latent heat and thermal conductivity. This study has used a salt hydrate from calcium chloride to be tested in air conditioning systems type chiller. Thermal characteristics were examined using temperature history (T-history) test and differential scanning calorimetry (DSC). The test results showed that the thermal characteristics of the salt hydrate has been a high latent heat and in accordance with the evaporator temperature. The use of salt hydrates in air conditioning system type chiller can reduce energy consumption by 51.5%.

  2. Extraction of CO2 from air samples for isotopic analysis and limits to ultra high precision delta18O determination in CO2 gas.

    PubMed

    Werner, R A; Rothe, M; Brand, W A

    2001-01-01

    The determination of delta18O values in CO2 at a precision level of +/-0.02 per thousand (delta-notation) has always been a challenging, if not impossible, analytical task. Here, we demonstrate that beyond the usually assumed major cause of uncertainty - water contamination - there are other, hitherto underestimated sources of contamination and processes which can alter the oxygen isotope composition of CO2. Active surfaces in the preparation line with which CO2 comes into contact, as well as traces of air in the sample, can alter the apparent delta18O value both temporarily and permanently. We investigated the effects of different surface materials including electropolished stainless steel, Duran glass, gold and quartz, the latter both untreated and silanized. CO2 frozen with liquid nitrogen showed a transient alteration of the 18O/16O ratio on all surfaces tested. The time to recover from the alteration as well as the size of the alteration varied with surface type. Quartz that had been ultrasonically cleaned for several hours with high purity water (0.05 microS) exhibited the smallest effect on the measured oxygen isotopic composition of CO2 before and after freezing. However, quartz proved to be mechanically unstable with time when subjected to repeated large temperature changes during operation. After several days of operation the gas released from the freezing step contained progressively increasing trace amounts of O2 probably originating from inclusions within the quartz, which precludes the use of quartz for cryogenically trapping CO2. Stainless steel or gold proved to be suitable materials after proper pre-treatment. To ensure a high trapping efficiency of CO2 from a flow of gas, a cold trap design was chosen comprising a thin wall 1/4" outer tube and a 1/8" inner tube, made respectively from electropolished stainless steel and gold. Due to a considerable 18O specific isotope effect during the release of CO2 from the cold surface, the thawing time had to

  3. Rotational infrared polarization modulator using a MEMS-based air turbine with different types of journal bearing

    NASA Astrophysics Data System (ADS)

    Hara, Motoaki; Tanaka, Shuji; Esashi, Masayoshi

    2003-03-01

    This paper describes rotational infrared polarization modulators using a micro-electromechanical-system-based (MEMS-based) air turbine with different types of journal bearing. Three types of journal bearing, circular, symmetrical two-lobed and asymmetrical seven-lobed journal bearing, were compared. Using an optical displacement meter and a high speed camera, it was confirmed that all turbines exhibit three modes of rotation: (a) low speed mode, (b) intermediate mode and (c) high speed mode in this order, when decreasing N2 flow rate to an aerostatic thrust bearing. In the low speed mode, the rotor is lifted up by excess flow to the thrust bearing, making a contact with an upper layer. In the high speed mode, the rotor is levitated without any contact to the upper and lower layers by balanced flow to the thrust bearing, and the maximum rotational speed of 74000 rpm was achieved using the asymmetrical seven-lobed bearing. The rotation in this mode is, however, discontinuous due to the collision between the rotor and the journal bearing. It was concluded that a journal bearing with sufficient load capacity is necessary for continuous high speed rotation.

  4. Biostratigraphy and biochronology of the Monte Hermoso Formation (early Pliocene) at its type locality, Buenos Aires Province, Argentina

    NASA Astrophysics Data System (ADS)

    Tomassini, Rodrigo L.; Montalvo, Claudia I.; Deschamps, Cecilia M.; Manera, Teresa

    2013-12-01

    The Monte Hermoso Formation, cropping out at its type locality of Farola Monte Hermoso (Buenos Aires Province), is a classical fossiliferous unit of the South American Neogene, highlighted by the abundance and diversity of its vertebrate remains. However, its biostratigraphy and age have been largely debated, and numerous discrepancies and controversies have been stated. In this regard, the result of the analysis of new materials recovered from the different levels of this formation, following a strict control of stratigraphic provenance, is here reported. As well, the provenance of specimens of previous collections has been evaluated. The studied assemblage consists of Osteichthyes, Amphibia, Reptilia, Aves and Mammalia. These latter are the most numerous and belong to the Didelphimorphia, Polydolopimorphia, Rodentia, Notoungulata, Litopterna and Xenarthra. The recorded taxa suggest no important faunistic variations among the different levels of the Monte Hermoso Formation that would imply significant chronological differences, and hence, justify the recognition of two biostratigraphic units. The analysis of the first and last records as well as the taxa considered as exclusive, does not support the validity of the biozones of Trigodon gaudryi and Neocavia depressidens previously proposed. On this basis, a new scheme for the Monte Hermoso Formation at its type locality is proposed, including a new single biostratigraphic unit. This unit is the Eumysops laeviplicatus Range Zone, which represents the biostratigraphic base for the Montehermosan Stage/Age of the early Pliocene.

  5. Feasibility intervention trial of two types of improved cookstoves in three resource-limited settings: study protocol for a randomized controlled trial

    PubMed Central

    2013-01-01

    Background Exposure to biomass fuel smoke is one of the leading risk factors for disease burden worldwide. International campaigns are currently promoting the widespread adoption of improved cookstoves in resource-limited settings, yet little is known about the cultural and social barriers to successful improved cookstove adoption and how these barriers affect environmental exposures and health outcomes. Design We plan to conduct a one-year crossover, feasibility intervention trial in three resource-limited settings (Kenya, Nepal and Peru). We will enroll 40 to 46 female primary cooks aged 20 to 49 years in each site (total 120 to 138). Methods At baseline, we will collect information on sociodemographic characteristics and cooking practices, and measure respiratory health and blood pressure for all participating women. An initial observational period of four months while households use their traditional, open-fire design cookstoves will take place prior to randomization. All participants will then be randomized to receive one of two types of improved, ventilated cookstoves with a chimney: a commercially-constructed cookstove (Envirofit G3300/G3355) or a locally-constructed cookstove. After four months of observation, participants will crossover and receive the other improved cookstove design and be followed for another four months. During each of the three four-month study periods, we will collect monthly information on self-reported respiratory symptoms, cooking practices, compliance with cookstove use (intervention periods only), and measure peak expiratory flow, forced expiratory volume at 1 second, exhaled carbon monoxide and blood pressure. We will also measure pulmonary function testing in the women participants and 24-hour kitchen particulate matter and carbon monoxide levels at least once per period. Discussion Findings from this study will help us better understand the behavioral, biological, and environmental changes that occur with a cookstove

  6. Frequency of Cytotoxic T Lymphocyte Precursors to Herpes Simplex Virus Type 1 as Determined by Limiting Dilution Analysis

    PubMed Central

    Rouse, Barry T.; Larsen, Hal S.; Wagner, Hermann

    1983-01-01

    The conditions for establishing a limiting dilution assay to measure cytotoxic T lymphocyte precursors (CTL-P) against herpes simplex virus type 1 (HSV-1) were determined. Analysis by Poisson statistics demonstrated that the estimated frequency of HSV-1-reactive cells in the spleens of normal mice was less than 1/250,000. In contrast, mice immunized previously with infectious HSV-1 demonstrated a CTL-P frequency between 1/3,500 and 1/15,670. The generation of a maximum cytotoxic T lymphocyte response required that mice be primed in vivo with infectious virus. Immunization with inactivated virus either failed to elicit detectable CTL-P frequencies or gave frequencies markedly less than those induced with infectious virus. To obtain positive cultures, the responder cell population had to be exposed to stimulator splenocytes expressing viral antigens. Normal splenocytes without virus or normal splenocytes with T cell growth factor did not result in significant cytotoxicity. Split culture analysis comparing cytotoxicity against syngeneic and allogeneic virus-infected targets provided evidence for specificity, H-2 restriction, and the T cell nature of the CTL-P. It was determined that precursors were eliminated by treatment with anti-Thy 1, Lyt 2.1, or Lyt 1.1, indicating the CTL-P were Lyt 1+2+ cells. Cytotoxicity was reduced after treatment of the responders with anti-Lyt 2 plus complement, which gave further evidence of the T cell nature of the cytotoxic T lymphocytes. These experiments demonstrated the feasibility of using the limiting dilution approach as a highly sensitive and quantitative means to measure the cell-mediated immune response to HSV-1 antigens. PMID:6299949

  7. SERS activity with tenfold detection limit optimization on a type of nanoporous AAO-based complex multilayer substrate

    NASA Astrophysics Data System (ADS)

    Sui, Chaofan; Wang, Kaige; Wang, Shuang; Ren, Junying; Bai, Xiaohong; Bai, Jintao

    2016-03-01

    Most of SERS applications are constricted by heterogeneous hotspots and aggregates of nanostructure, which result in low sensitivity and poor reproducibility of characteristic signals. This work intends to introduce SERS properties of a type of SERS-active substrate, Au-CuCl2-AAO, which is innovatively developed on a porous anodic alumina oxide (AAO) template. Spectral measuring results of Rhodamine 6G (R6G) on this substrate optimized by controlling morphology and gold thickness showed that enhancement factor (2.30 × 107) and detection limit (10-10 M) were both improved and represented better performance than its template AAO. Homogenous hot spots across the region of interest were achieved by scanning SERS intensity distribution for the band at 1505 cm-1 in 5 × 5 μm2 area. Furthermore, the promising SERS activity of the flower-patterned substrate was theoretically explained through simulation of the electromagnetic field distribution. In addition, this SERS substrate is proposed for applications within the field of chemical and biochemical analyses.Most of SERS applications are constricted by heterogeneous hotspots and aggregates of nanostructure, which result in low sensitivity and poor reproducibility of characteristic signals. This work intends to introduce SERS properties of a type of SERS-active substrate, Au-CuCl2-AAO, which is innovatively developed on a porous anodic alumina oxide (AAO) template. Spectral measuring results of Rhodamine 6G (R6G) on this substrate optimized by controlling morphology and gold thickness showed that enhancement factor (2.30 × 107) and detection limit (10-10 M) were both improved and represented better performance than its template AAO. Homogenous hot spots across the region of interest were achieved by scanning SERS intensity distribution for the band at 1505 cm-1 in 5 × 5 μm2 area. Furthermore, the promising SERS activity of the flower-patterned substrate was theoretically explained through simulation of the

  8. Biochemical acclimation, stomatal limitation and precipitation patterns underlie decreases in photosynthetic stimulation of soybean (Glycine max) at elevated [CO₂] and temperatures under fully open air field conditions.

    PubMed

    Rosenthal, David M; Ruiz-Vera, Ursula M; Siebers, Matthew H; Gray, Sharon B; Bernacchi, Carl J; Ort, Donald R

    2014-09-01

    The net effect of elevated [CO2] and temperature on photosynthetic acclimation and plant productivity is poorly resolved. We assessed the effects of canopy warming and fully open air [CO2] enrichment on (1) the acclimation of two biochemical parameters that frequently limit photosynthesis (A), the maximum carboxylation capacity of Rubisco (Vc,max) and the maximum potential linear electron flux through photosystem II (Jmax), (2) the associated responses of leaf structural and chemical properties related to A, as well as (3) the stomatal limitation (l) imposed on A, for soybean over two growing seasons in a conventionally managed agricultural field in Illinois, USA. Acclimation to elevated [CO2] was consistent over two growing seasons with respect to Vc,max and Jmax. However, elevated temperature significantly decreased Jmax contributing to lower photosynthetic stimulation by elevated CO2. Large seasonal differences in precipitation altered soil moisture availability modulating the complex effects of elevated temperature and CO2 on biochemical and structural properties related to A. Elevated temperature also reduced the benefit of elevated [CO2] by eliminating decreases in stomatal limitation at elevated [CO2]. These results highlight the critical importance of considering multiple environmental factors (i.e. temperature, moisture, [CO2]) when trying to predict plant productivity in the context of climate change. PMID:25113459

  9. Thermal infrared properties of classical and type II Cepheids. Diffraction limited 10 μm imaging with VLT/VISIR

    NASA Astrophysics Data System (ADS)

    Gallenne, A.; Kervella, P.; Mérand, A.

    2012-02-01

    We present new thermal infrared (IR) photometry and spectral energy distributions (SEDs) of eight classical Cepheids (type I) and three type II Cepheids, using VISIR thermal IR photometric measurements, supplemented with literature data. We used the BURST mode of the instrument to get diffraction-limited images at 8.59, 11.25, and 11.85 μm. The SEDs show a IR excess at wavelengths longer than 10 μm in ten of the eleven stars. We tentatively attribute these excesses to circumstellar emission created by mass loss from the Cepheids. On the basis of some hypotheses for the dust composition, we estimate a total mass of the envelope ranging from 10-10 to 10-8 M⊙. We also detect a spatially extended emission around AX Cir, X Sgr, W Sgr, Y Oph, and U Car, while we do not resolve the circumstellar envelope (CSE) of the other stars. The averaged circumstellar envelope brightnesses relative to the stellar photosphere are α(AX Cir) = 13.8 ± 2.5%,α(X Sgr) = 7.9 ± 1.4%,α(W Sgr) = 3.8 ± 0.6%,α(Y Oph) = 15.1 ± 1.4%, and α(U Car) = 16.3 ± 1.4% at 8.59 μm. With this study, we extend the number of classical Cepheids with detected CSEs from 9 to 14, confirming that at least a large fraction of all Cepheids are experiencing significant mass loss. The presence of these CSEs may also impact the future use of Cepheids as standard candles at near and thermal infrared wavelengths. Based on observations made with ESO telescopes at Paranal observatory under program ID 081.D-0165(A).Table 2 is only available in electronic form at http://www.aanda.org

  10. Phylogenetic and molecular analyses of human parainfluenza type 3 virus in Buenos Aires, Argentina, between 2009 and 2013: The emergence of new genetic lineages.

    PubMed

    Goya, Stephanie; Mistchenko, Alicia Susana; Viegas, Mariana

    2016-04-01

    Despite that human parainfluenza type 3 viruses (HPIV3) are one of the leading causes of acute lower respiratory tract infections in children under five, there is no licensed vaccine and there is limited current information on the molecular characteristics of regional and global circulating strains. The aim of this study was to describe the molecular characterization of HPIV3 circulating in Buenos Aires. We performed a genetic and phylogenetic analysis of the HN glycoprotein gene. Between 2009 and 2013, 124 HPIV3-positive samples taken from hospitalized pediatric patients were analyzed. Four new genetic lineages were described. Among them, C1c and C3d lineages showed local circulation patterns, whereas C3e and C3f comprised sequences from very distant countries. Despite the diversity of the described genotypes, C3a and C3d predominated over the others, the latter was present during the first years of the study and it was progressively replaced by C3a. Molecular analyses showed 28 non-synonymous substitutions; of these, 13 were located in potentially predicted B-cell epitopes. Taken together, the emergence of genetic lineages and the information of the molecular characteristics of HN protein may contribute to the general knowledge of HPIV3 molecular epidemiology for future vaccine development and antiviral therapies. PMID:26780643

  11. Summary of Stimulated Raman Scattering Experiments in the Nova Air-Path and Projected Nova and Nova II System Performance Limits

    SciTech Connect

    Henesian, M; Swift, C D; Murray, J R

    2007-07-17

    The authors present the results of high intensity beam propagation experiments conducted with the Nova laser system to investigate the occurrence of stimulated rotational Raman scattering (SRRS) from atmospheric nitrogen in the beam path. Enclosed is a preprint entitled ''Stimulated Rotational Raman Scattering in Nitrogen in Long Air Paths'' that they have published in the November issue of Optics Letters. The physics issues associated with SRRS are discussed at length in the preprint. The small signal steady-state SRRS gain coefficient that they determined from threshold measurements is in excellent agreement with recent direct SRRS gain measurements by Bischel, et al., at SRI, and is in good agreement with early gain estimates from Averbakh, et al., in the Soviet Union. Consequently, they have a high degree of confidence in the gain coefficient. In addition, threshold SRRS experiments on the long air-path Nova II system are in substantial agreement with the earlier Nova experiments. Nova and Nova II system performance limitations were not critically addressed in the publication so they shall discuss these issues in this paper.

  12. Flocking dynamics and mean-field limit in the Cucker-Smale-type model with topological interactions

    NASA Astrophysics Data System (ADS)

    Haskovec, Jan

    2013-10-01

    We introduce a Cucker-Smale-type model for flocking, where the strength of interaction between two agents depends on their relative separation (called “topological distance” in previous works), which is the number of intermediate individuals separating them. This makes the model scale-free and is motivated by recent extensive observations of starling flocks, suggesting that the interaction ruling animal collective behavior depends on topological rather than the metric distance. We study the conditions leading to asymptotic flocking in the topological model, defined as the convergence of the agents’ velocities to a common vector. The shift from metric to topological interactions requires development of new analytical methods, taking into account the graph-theoretical nature of the problem. Moreover, we provide a rigorous derivation of the mean-field limit of large populations, recovering kinetic and hydrodynamic descriptions. In particular, we introduce the novel concept of relative separation in continuum descriptions, which is applicable to a broad variety of models of collective behavior. As an example, we shortly discuss a topological modification of the attraction-repulsion model and illustrate with numerical simulations that the modified model produces interesting new pattern dynamics.

  13. SERS activity with tenfold detection limit optimization on a type of nanoporous AAO-based complex multilayer substrate.

    PubMed

    Sui, Chaofan; Wang, Kaige; Wang, Shuang; Ren, Junying; Bai, Xiaohong; Bai, Jintao

    2016-03-21

    Most of SERS applications are constricted by heterogeneous hotspots and aggregates of nanostructure, which result in low sensitivity and poor reproducibility of characteristic signals. This work intends to introduce SERS properties of a type of SERS-active substrate, Au-CuCl2-AAO, which is innovatively developed on a porous anodic alumina oxide (AAO) template. Spectral measuring results of Rhodamine 6G (R6G) on this substrate optimized by controlling morphology and gold thickness showed that enhancement factor (2.30 × 10(7)) and detection limit (10(-10) M) were both improved and represented better performance than its template AAO. Homogenous hot spots across the region of interest were achieved by scanning SERS intensity distribution for the band at 1505 cm(-1) in 5 × 5 μm(2) area. Furthermore, the promising SERS activity of the flower-patterned substrate was theoretically explained through simulation of the electromagnetic field distribution. In addition, this SERS substrate is proposed for applications within the field of chemical and biochemical analyses. PMID:26911325

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

    NASA Astrophysics Data System (ADS)

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

    2011-05-01

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

  15. Diagnosing AIRS Sampling with CloudSat Cloud Classes

    NASA Technical Reports Server (NTRS)

    Fetzer, Eric; Yue, Qing; Guillaume, Alexandre; Kahn, Brian

    2011-01-01

    AIRS yield and sampling vary with cloud state. Careful utilization of collocated multiple satellite sensors is necessary. Profile differences between AIRS and ECMWF model analyses indicate that AIRS has high sampling and excellent accuracy for certain meteorological conditions. Cloud-dependent sampling biases may have large impact on AIRS L2 and L3 data in climate research. MBL clouds / lower tropospheric stability relationship is one example. AIRS and CloudSat reveal a reasonable climatology in the MBL cloud regime despite limited sampling in stratocumulus. Thermodynamic parameters such as EIS derived from AIRS data map these cloud conditions successfully. We are working on characterizing AIRS scenes with mixed cloud types.

  16. Air Bearing Lift Pad (ABLP)

    NASA Technical Reports Server (NTRS)

    Dane, Dan H.; Blaise, Herman T.

    1968-01-01

    Typical air bearings float on air films of only a few thousandths of an inch and so will only operate above very smooth, even surfaces. For the mechanical simulation of space, the small drag of the bladder type air pads is much more than can be coped with, and the practicality of large floor areas being machined for precision air bearings is nonexistent. To enable operation above surfaces that undulate slightly or feature cracks and discontinuities, an ABLP has been developed. It consists of a rigid pad beneath which an inflatable bladder is mounted. The bladder is inflated with air which then escapes through passages into a cavity in the center of the bladder to produce the lifting energy. As the air escapes about the perimeter of the bladder, a certain degree of balance and equilibrium is imparted to the pad as it is able to move a limited weight across slightly uneven surfaces.

  17. The Australian Air Quality Forecasting System: Exploring First Steps Towards Determining The Limits of Predictability For Short-Term Ozone Forecasting

    NASA Astrophysics Data System (ADS)

    Cope, M. E.; Hess, G. D.; Lee, S.; Tory, K. J.; Burgers, M.; Dewundege, P.; Johnson, M.

    2005-08-01

    Physical parameterisations of turbulent transfer processes in the atmospheric boundary layer, such as the stability parameterisations developed by Joost Businger, and recent advances in computing capabilities, have been important factors leading to the emergence of operational, numerical air quality forecasting systems. The present paper investigates the performance of the Australian Air Quality Forecasting System (AAQFS) in forecasting the peak 1 h ozone for the current or next day. These 24/36 h forecasts are generated for the Sydney and Melbourne regions and issued twice daily. Quantitative evidence is presented of the potential for the AAQFS to provide accurate numerical air quality forecasts. A second goal is to provide an initial benchmark for investigating the limits of predictability for air quality in the Sydney and Melbourne regions by looking at the dependence of the forecasts on the domain spatial scale (while maintaining the same model grid resolution), the starting time and length of the forecast (0000 UTC starts are 36-h forecasts and 1200 UTC starts are 24-h forecasts), and the sophistication of the photochemical mechanism (simple chemistry, Generic Reaction Set (GRS) and complex chemistry, Carbon Bond IV (CBIV)). The probability of detection by the forecast model is much better than persistence, showing considerable skill. The normalised bias, in general, decreases going from regional scale to sub-regional scale and becomes negative at the station scale. In Melbourne the gross error increases as the domain spatial scale decreases, but in Sydney there is a dip in the error at the sub-regional scale due to a sampling artifact. Better results are obtained at the smaller domain scales for 1200 UTC forecasts in Sydney. These are attributed to the shorter forecast period and secondarily to greater model spin-up effects at 0000 UTC. In Melbourne the results are ambiguous. Similar conclusions are derived from scatter plots of forecasts versus observations

  18. Technology of oxygen production in the membranecryogenic air separation system for a 600 MW oxy-type pulverized bed boiler

    NASA Astrophysics Data System (ADS)

    Berdowska, Sylwia; Skorek-Osikowska, Anna

    2012-09-01

    In this paper the results of the thermodynamic analysis of the oxy-combustion type pulverized bed boiler integrated with a hybrid, membrane- cryogenic oxygen separation installation are presented. For the calculations a 600 MW boiler with live steam parameters at 31.1 MPa /654.9 oC and reheated steam at 6.15 MPa/672.4 oC was chosen. In this paper the hybrid membrane-cryogenic technology as oxygen production unit for pulverized bed boiler was proposed. Such an installation consists of a membrane module and two cryogenic distillation columns. Models of these installations were built in the Aspen software. The energy intensity of the oxygen production process in the hybrid system was compared with the cryogenic technology. The analysis of the influence of membrane surface area on the energy intensity of the process of air separation as well as the influence of oxygen concentration at the inlet to the cryogenic installation on the energy intensity of a hybrid unit was performed.

  19. Monte Carlo simulation of a quantum noise limited Čerenkov detector based on air-spaced light guiding taper for megavoltage x-ray imaging

    SciTech Connect

    Teymurazyan, A.; Rowlands, J. A.; Pang, G.

    2014-04-15

    Purpose: Electronic Portal Imaging Devices (EPIDs) have been widely used in radiation therapy and are still needed on linear accelerators (Linacs) equipped with kilovoltage cone beam CT (kV-CBCT) or MRI systems. Our aim is to develop a new high quantum efficiency (QE) Čerenkov Portal Imaging Device (CPID) that is quantum noise limited at dose levels corresponding to a single Linac pulse. Methods: Recently a new concept of CPID for MV x-ray imaging in radiation therapy was introduced. It relies on Čerenkov effect for x-ray detection. The proposed design consisted of a matrix of optical fibers aligned with the incident x-rays and coupled to an active matrix flat panel imager (AMFPI) for image readout. A weakness of such design is that too few Čerenkov light photons reach the AMFPI for each incident x-ray and an AMFPI with an avalanche gain is required in order to overcome the readout noise for portal imaging application. In this work the authors propose to replace the optical fibers in the CPID with light guides without a cladding layer that are suspended in air. The air between the light guides takes on the role of the cladding layer found in a regular optical fiber. Since air has a significantly lower refractive index (∼1 versus 1.38 in a typical cladding layer), a much superior light collection efficiency is achieved. Results: A Monte Carlo simulation of the new design has been conducted to investigate its feasibility. Detector quantities such as quantum efficiency (QE), spatial resolution (MTF), and frequency dependent detective quantum efficiency (DQE) have been evaluated. The detector signal and the quantum noise have been compared to the readout noise. Conclusions: Our studies show that the modified new CPID has a QE and DQE more than an order of magnitude greater than that of current clinical systems and yet a spatial resolution similar to that of current low-QE flat-panel based EPIDs. Furthermore it was demonstrated that the new CPID does not require an

  20. AIRSLUG: A fortran program for the computation of type curves to estimate transmissivity and storativity from prematurely terminated air-pressurized slug tests

    USGS Publications Warehouse

    Greene, E.A.; Shapiro, A.M.

    1998-01-01

    The Fortran code AIRSLUG can be used to generate the type curves needed to analyze the recovery data from prematurely terminated air-pressurized slug tests. These type curves, when used with a graphical software package, enable the engineer or scientist to analyze field tests to estimate transmissivity and storativity. Prematurely terminating the slug test can significantly reduce the overall time needed to conduct the test, especially at low-permeability sites, thus saving time and money.The Fortran code AIRSLUG can be used to generate the type curves needed to analyze the recovery data from prematurely terminated air-pressurized slug tests. These type curves, when used with a graphical software package, enable the engineer or scientist to analyze field tests to estimate transmissivity and storativity. Prematurely terminating the slug test can significantly reduce the overall time needed to conduct the test, especially at low-permeability sites, thus saving time and money.

  1. Use of Oriented Spray Nozzles to Set the Vapor-Air Flow in Rotary Motion in the Superspray Space of the Evaporative Chimney-Type Tower

    NASA Astrophysics Data System (ADS)

    Dobrego, K. V.; Davydenko, V. F.; Koznacheev, I. A.

    2016-01-01

    The present paper considers the problem of upgrading the thermal efficiency of chimney-type evaporative cooling towers due to the rotary motion of the vapor-air flow in the superspray space. To set the vapor-air flow in rotary motion, we propose to use the momentum of the sprayed water. It has been shown that the existing parameters of spray nozzles permit setting up to 30% of the water flow momentum in translatory motion, which is enough for changing considerably the aerodynamics of the vapor-air flow in the superspray space and improving the operation of the cooling tower. The optimal angle of axial inclination of the spray cone has been estimated. Recommendations are given and problems have been posed for engineering realization of the proposed technologies in a chimney-type cooling tower.

  2. Sustained enhancement of photosynthesis in coffee trees grown under free-air CO2 enrichment conditions: disentangling the contributions of stomatal, mesophyll, and biochemical limitations.

    PubMed

    DaMatta, Fábio M; Godoy, Alice G; Menezes-Silva, Paulo E; Martins, Samuel C V; Sanglard, Lílian M V P; Morais, Leandro E; Torre-Neto, André; Ghini, Raquel

    2016-01-01

    Coffee (Coffea spp.), a globally traded commodity, is a slow-growing tropical tree species that displays an improved photosynthetic performance when grown under elevated atmospheric CO2 concentrations ([CO2]). To investigate the mechanisms underlying this response, two commercial coffee cultivars (Catuaí and Obatã) were grown using the first free-air CO2 enrichment (FACE) facility in Latin America. Measurements were conducted in two contrasting growth seasons, which were characterized by the high (February) and low (August) sink demand. Elevated [CO2] led to increases in net photosynthetic rates (A) in parallel with decreased photorespiration rates, with no photochemical limitations to A. The stimulation of A by elevated CO2 supply was more prominent in August (56% on average) than in February (40% on average). Overall, the stomatal and mesophyll conductances, as well as the leaf nitrogen and phosphorus concentrations, were unresponsive to the treatments. Photosynthesis was strongly limited by diffusional constraints, particularly at the stomata level, and this pattern was little, if at all, affected by elevated [CO2]. Relative to February, starch pools (but not soluble sugars) increased remarkably (>500%) in August, with no detectable alteration in the maximum carboxylation capacity estimated on a chloroplast [CO2] basis. Upregulation of A by elevated [CO2] took place with no signs of photosynthetic downregulation, even during the period of low sink demand, when acclimation would be expected to be greatest. PMID:26503540

  3. Sustained enhancement of photosynthesis in coffee trees grown under free-air CO2 enrichment conditions: disentangling the contributions of stomatal, mesophyll, and biochemical limitations

    PubMed Central

    DaMatta, Fábio M.; Godoy, Alice G.; Menezes-Silva, Paulo E.; Martins, Samuel C.V.; Sanglard, Lílian M.V.P.; Morais, Leandro E.; Torre-Neto, André; Ghini, Raquel

    2016-01-01

    Coffee (Coffea spp.), a globally traded commodity, is a slow-growing tropical tree species that displays an improved photosynthetic performance when grown under elevated atmospheric CO2 concentrations ([CO2]). To investigate the mechanisms underlying this response, two commercial coffee cultivars (Catuaí and Obatã) were grown using the first free-air CO2 enrichment (FACE) facility in Latin America. Measurements were conducted in two contrasting growth seasons, which were characterized by the high (February) and low (August) sink demand. Elevated [CO2] led to increases in net photosynthetic rates (A) in parallel with decreased photorespiration rates, with no photochemical limitations to A. The stimulation of A by elevated CO2 supply was more prominent in August (56% on average) than in February (40% on average). Overall, the stomatal and mesophyll conductances, as well as the leaf nitrogen and phosphorus concentrations, were unresponsive to the treatments. Photosynthesis was strongly limited by diffusional constraints, particularly at the stomata level, and this pattern was little, if at all, affected by elevated [CO2]. Relative to February, starch pools (but not soluble sugars) increased remarkably (>500%) in August, with no detectable alteration in the maximum carboxylation capacity estimated on a chloroplast [CO2] basis. Upregulation of A by elevated [CO2] took place with no signs of photosynthetic downregulation, even during the period of low sink demand, when acclimation would be expected to be greatest. PMID:26503540

  4. 42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

    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 supplied-air respirators, demand and pressure-demand classes; test requirements. 84.163 Section 84.163 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL...

  5. 42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

    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 supplied-air respirators, demand and pressure-demand classes; test requirements. 84.163 Section 84.163 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL...

  6. 42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

    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 supplied-air respirators, demand and pressure-demand classes; test requirements. 84.163 Section 84.163 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL...

  7. 42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

    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 supplied-air respirators, demand and pressure-demand classes; test requirements. 84.163 Section 84.163 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL...

  8. 42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

    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 supplied-air respirators, demand and pressure-demand classes; test requirements. 84.163 Section 84.163 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL...

  9. Two reduced form air quality modeling techniques for rapidly calculating pollutant mitigation potential across many sources, locations and precursor emission types

    EPA Science Inventory

    Due to the computational cost of running regional-scale numerical air quality models, reduced form models (RFM) have been proposed as computationally efficient simulation tools for characterizing the pollutant response to many different types of emission reductions. The U.S. Envi...

  10. Design Optimization and the Limits of Steady-State Heating Efficiency for Conventional Single-Speed Air-Source Heat Pumps

    SciTech Connect

    Rice, C.K.

    2001-06-06

    The ORNL Heat Pump Model and an optimizing program were used to explore the limits of steady-state heating efficiency for conventional air-source heat pumps. The method used allows for the simultaneous optimization of ten selected design variables, taking proper account of their interactions, while constraining other parameters to chosen limits or fixed values. Designs were optimized for a fixed heating capacity, but the results may be scaled to other capacities. Substantial performance improvement is predicted compared to today's state of the art heat pump. With increased component efficiencies that are expected in the near future and with modest increases in heat exchanger area, a 28% increase in heating efficiency is predicted; for long-term improvements with considerably larger heat exchangers, a 56% increase is possible. The improved efficiencies are accompanied by substantial reductions in the requirements for compressor and motor size. The predicted performance improvements are attributed not only to improved components and larger heat exchangers but also to the use of an optimizing design procedure. Deviations from the optimized design may be necessary to make use of available component sizes and to maintain good cooling-mode performance while improving the heating efficiency. Sensitivity plots (i.e., COP as a function of one or more design parameters) were developed to explore design flexibilities and to evaluate their consequences. The performance of the optimized designs was compared to that of modified ideal cycles to assess the factors that limit further improvement. It is hoped that the design methods developed will be useful to designers in the heat pump industry.

  11. 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...

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

    NASA Astrophysics Data System (ADS)

    Shimizu, Hirofumi; Sanada, Yuji

    2011-11-01

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

  13. Aerosolized ZnO nanoparticles induce toxicity in alveolar type II epithelial cells at the air-liquid interface

    SciTech Connect

    Xie, Yumei; Williams, Nolann G.; Tolic, Ana; Chrisler, William B.; Teeguarden, Justin G.; Maddux, Bettye L.; Pounds, Joel G.; Laskin, Alexander; Orr, Galya

    2012-01-20

    The majority of in vitro studies characterizing the impact of engineered nanoparticles (NPs) on cells that line the respiratory tract were conducted in cells exposed to NPs in suspension. This approach introduces processes that are unlikely to occur during inhaled NP exposures in vivo, such as the shedding of toxic doses of dissolved ions. ZnO NPs are used extensively and pose significant sources for human exposure. Exposures to airborne ZnO NPs can induce adverse effects, but the relevance of the dissolved Zn2+ to the observed effects in vivo is still unclear. Our goal was to mimic in vivo exposures to airborne NPs and decipher the contribution of the intact NP from the contribution of the dissolved ions to airborne ZnO NP toxicity. We established the exposure of alveolar type II epithelial cells to aerosolized NPs at the air-liquid interface (ALI), and compared the impact of aerosolized ZnO NPs and NPs in suspension at the same cellular doses, measured as the number of particles per cell. By evaluating membrane integrity and cell viability 6 and 24 hours post exposure we found that aerosolized NPs induced toxicity at the ALI at doses that were in the same order of magnitude as doses required to induce toxicity in submersed cultures. In addition, distinct patterns of oxidative stress were observed in the two exposure systems. These observations unravel the ability of airborne ZnO NPs to induce toxicity without the contribution of dissolved Zn2+ and suggest distinct mechanisms at the ALI and in submersed cultures.

  14. An intermittent control model of flexible human gait using a stable manifold of saddle-type unstable limit cycle dynamics.

    PubMed

    Fu, Chunjiang; Suzuki, Yasuyuki; Kiyono, Ken; Morasso, Pietro; Nomura, Taishin

    2014-12-01

    Stability of human gait is the ability to maintain upright posture during walking against external perturbations. It is a complex process determined by a number of cross-related factors, including gait trajectory, joint impedance and neural control strategies. Here, we consider a control strategy that can achieve stable steady-state periodic gait while maintaining joint flexibility with the lowest possible joint impedance. To this end, we carried out a simulation study of a heel-toe footed biped model with hip, knee and ankle joints and a heavy head-arms-trunk element, working in the sagittal plane. For simplicity, the model assumes a periodic desired joint angle trajectory and joint torques generated by a set of feed-forward and proportional-derivative feedback controllers, whereby the joint impedance is parametrized by the feedback gains. We could show that a desired steady-state gait accompanied by the desired joint angle trajectory can be established as a stable limit cycle (LC) for the feedback controller with an appropriate set of large feedback gains. Moreover, as the feedback gains are decreased for lowering the joint stiffness, stability of the LC is lost only in a few dimensions, while leaving the remaining large number of dimensions quite stable: this means that the LC becomes saddle-type, with a low-dimensional unstable manifold and a high-dimensional stable manifold. Remarkably, the unstable manifold remains of low dimensionality even when the feedback gains are decreased far below the instability point. We then developed an intermittent neural feedback controller that is activated only for short periods of time at an optimal phase of each gait stride. We characterized the robustness of this design by showing that it can better stabilize the unstable LC with small feedback gains, leading to a flexible gait, and in particular we demonstrated that such an intermittent controller performs better if it drives the state point to the stable manifold, rather

  15. Air-tolerant Fabrication and Enhanced Thermoelectric Performance of n-Type Single-walled Carbon Nanotubes Encapsulating 1,1'-Bis(diphenylphosphino)ferrocene.

    PubMed

    Nonoguchi, Yoshiyuki; Iihara, Yu; Ohashi, Kenji; Murayama, Tomoko; Kawai, Tsuyoshi

    2016-09-01

    The thermally-triggered n-type doping of single-walled carbon nanotubes is demonstrated using 1,1'-bis(diphenylphosphino)ferrocene, a novel n-type dopant. Through a simple thermal vacuum process, the phosphine compounds are moderately encapsulated inside single-walled carbon nanotubes. The encapsulation into SWNTs is carefully characterized using Raman/X-ray spectroscopy and transmission electron microscopy. This easy-to-handle doping with air-stable precursors for n-type SWNTs enables the large-scale fabrication of thermoelectric materials showing an excellent power factor exceeding approximately 240 μW mK(-2) . PMID:27439731

  16. 40 CFR 52.30 - Criteria for limiting application of sanctions under section 110(m) of the Clean Air Act on a...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and/or implementing air pollution controls for one, or any combination of one or more of the following... sanctions under section 110(m) of the Clean Air Act on a statewide basis. 52.30 Section 52.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION...

  17. 40 CFR 52.30 - Criteria for limiting application of sanctions under section 110(m) of the Clean Air Act on a...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... sanctions under section 110(m) of the Clean Air Act on a statewide basis. 52.30 Section 52.30 Protection of...(m) of the Clean Air Act on a statewide basis. (a) Definitions. For the purpose of this section: (1... 179(a) of the Clean Air Act is made, EPA will not impose sanctions under section 110(m) of the Act...

  18. 40 CFR 52.30 - Criteria for limiting application of sanctions under section 110(m) of the Clean Air Act on a...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... sanctions under section 110(m) of the Clean Air Act on a statewide basis. 52.30 Section 52.30 Protection of...(m) of the Clean Air Act on a statewide basis. (a) Definitions. For the purpose of this section: (1... 179(a) of the Clean Air Act is made, EPA will not impose sanctions under section 110(m) of the Act...

  19. 40 CFR 52.30 - Criteria for limiting application of sanctions under section 110(m) of the Clean Air Act on a...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... sanctions under section 110(m) of the Clean Air Act on a statewide basis. 52.30 Section 52.30 Protection of...(m) of the Clean Air Act on a statewide basis. (a) Definitions. For the purpose of this section: (1... 179(a) of the Clean Air Act is made, EPA will not impose sanctions under section 110(m) of the Act...

  20. 40 CFR 52.30 - Criteria for limiting application of sanctions under section 110(m) of the Clean Air Act on a...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... sanctions under section 110(m) of the Clean Air Act on a statewide basis. 52.30 Section 52.30 Protection of...(m) of the Clean Air Act on a statewide basis. (a) Definitions. For the purpose of this section: (1... 179(a) of the Clean Air Act is made, EPA will not impose sanctions under section 110(m) of the Act...

  1. Effects of frequency on fatigue behavior of type 316 low-carbon, nitrogen-added stainless steel in air and mercury for the spallation neutron source

    NASA Astrophysics Data System (ADS)

    Tian, H.; Liaw, P. K.; Fielden, D. E.; Brooks, C. R.; Brotherton, M. D.; Jiang, L.; Yang, B.; Wang, H.; Strizak, J. P.; Mansur, L. K.

    2006-01-01

    The high-cycle fatigue behavior of type 316 low-carbon, nitrogen-added (LN) stainless steel (SS), the prime-candidate target-container material for the spallation neutron source (SNS), was investigated in air and mercury. Test frequencies ranged from 0.2 to 10 Hz with an R ratio of -1, and 10 to 700 Hz with an R ratio of 0.1. During tension-compression fatigue studies, a significant increase in the specimen temperature was observed at 10 Hz in air, which decreased the fatigue life of the 316 LN SS relative to that at 0.2 Hz. Companion tests in air were carried out, while cooling the specimen with nitrogen gas at 10 Hz in air. In these experiments, fatigue lives were comparable at 10 Hz in air with nitrogen cooling and at 0.2 Hz in air. During tension-tension fatigue studies, a higher specimen temperature was observed at 700 than at 10 Hz. After cooling the specimen, comparable fatigue lives were found at 10 and at 700 Hz. The frequency effect on the fatigue life in mercury was found to be much less than that in air, due to the fact that mercury acts as an effective coolant during the fatigue experiment. Striation spacing on the fracture surface at different test frequencies was closely examined, relative to calculated Δ K values, during fatigue of the 316 LN SS. Specimen self-heating has to be considered in understanding fatigue characteristics of 316 LN SS in air and mercury.

  2. Effect of monoclonal antibodies on limited proteolysis of native glycoprotein gD of herpes simplex virus type 1

    SciTech Connect

    Eisenberg, R.J.; Long, D.; Pereira, L.; Hampar, B.; Zweig, M.; Cohen, G.H.

    1982-02-01

    We examined the properties of 17 monoclonal antibodies to glycoprotein gD of herpes simplex type 1 (HSV-1) (gD-1) and HSV-2 (gD-2). The antibodies recognized eight separate determinants of gD, based on differences in radioimmuno-precipitation and neutralization assays. The determinants were distributed as follows: three were gD-1 specific, one was gD-2 specific, and four were type common. Several type-specific and type-common determinants appeared to be involved in neutralization. We developed a procedure for examining the effect that binding of monoclonal antibody has on proteolysis of native gD-1 by Staphylococcus aureus protease V8. We showed that several different patterns of protease V8 cleavage were obtained, depending on the monoclonal antibody used. The proteolysis patterns were generally consistent with the immunological groupings. With four groups of antibodies, we found that fragments of gD-1 remained bound to antibody after V8 treatment. A 38,000-dalton fragment remained bound to antibodies in three different groups of monoclonal antibodies. This fragment appeared to contain one type-common and two type-specific determinants. A 12,000-dalton fragment remained bound to antibodies belonging to one type-common group of monoclonal antibodies. Tryptic peptide analysis revealed that the 12,000-dalton fragment represented a portion of the 38,000-dalton fragment and was enriched in a type-common arginine tryptic peptide.

  3. Monitoring Air Pollution In and Around the Premises of Industrial Parks Using Two Types of Electronic Nose and Gas Chromatography-Ion Trap Mass Spectrometry

    SciTech Connect

    Liu, Jen Yu; Ling, Yong Chien, Sr.

    2004-03-31

    Two types of electronic nose and GC-MS were used to monitor air pollution in the premises of seven industrial parks. Real-time analysis of air at the sites was performed using portable electronic noses. Air samples were analyzed from the up and down stream direction along the wind flow to investigate the effect or distribution of the pollutants on the surrounding environment. The advantage of multisensors in spatially resolved sensing for direct multicomponent analysis was explored to minimize tedious sample preparation procedure. Electronic nose could give characteristic odor fingerprints, which were correlated with the pollutants analyzed using GC-MS providing detailed diagnostic information such as the presence of hydrocarbons, halocarbons, phenols, nitrogenous benzenes, sulfur compounds, lipid-derived compounds, polysiloxanes, etc. Subsequent principal component analysis helped in identifying the source of pollutants. The applicability of the electronic nose was demonstrated confirming it to be a simple and rapid screening method for identifying the pollutant source.

  4. 20 CFR 645.235 - What types of activities are subject to the administrative cost limit on Welfare-to-Work grants?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false What types of activities are subject to the administrative cost limit on Welfare-to-Work grants? 645.235 Section 645.235 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR PROVISIONS GOVERNING WELFARE-TO-WORK GRANTS General Program and Administrative Requirements...

  5. Hazardous air pollutant emissions from gas-fired combustion sources: emissions and the effects of design and fuel type.

    PubMed

    England, G C; McGrath, T P; Gilmer, L; Seebold, J G; Lev-On, M; Hunt, T

    2001-01-01

    Air emissions from gas-fired combustion devices such as boilers, process heaters, gas turbines and stationary reciprocating engines contain hazardous air pollutants (HAPs) subjected to consideration under the federal clean air act (CAA). This work presents a recently completed major research project to develop an understanding of HAP emissions from gas-fired boilers and process heaters and new HAP emission factors based on field emission tests of gas-fired external combustion devices used in the petroleum industry. The effect of combustion system design and operating parameters on HAP emissions determined by both field and research tests are discussed. Data from field tests of gas-fired petroleum industry boilers and heaters generally show very low emission levels of organic HAPs. A comparison of the emission data for boilers and process heaters, including units with and without various forms of NOx emission controls, showed no significant difference in organic HAP emission characteristics due to process or burner design. This conclusion is also supported by the results of research tests with different burner designs. Based on field tests of units fired with natural gas and various petroleum industry process gases and research tests in which gas composition was intentionally varied, organic HAP emissions were not determined to be significantly affected by the gas composition. Research data indicate that elevated organic HAP emission levels are found only under extreme operating conditions (starved air or high excess air combustion) associated with poor combustion. PMID:11219701

  6. Functional Interplay between Type I and II Interferons Is Essential to Limit Influenza A Virus-Induced Tissue Inflammation

    PubMed Central

    Stifter, Sebastian A.; Bhattacharyya, Nayan; Pillay, Roman; Flórido, Manuela; Triccas, James A.; Britton, Warwick J.; Feng, Carl G.

    2016-01-01

    Host control of influenza A virus (IAV) is associated with exuberant pulmonary inflammation characterized by the influx of myeloid cells and production of proinflammatory cytokines including interferons (IFNs). It is unclear, however, how the immune system clears the virus without causing lethal immunopathology. Here, we demonstrate that in addition to its known anti-viral activity, STAT1 signaling coordinates host inflammation during IAV infection in mice. This regulatory mechanism is dependent on both type I IFN and IFN-γ receptor signaling and, importantly, requires the functional interplay between the two pathways. The protective function of type I IFNs is associated with not only the recruitment of classical inflammatory Ly6Chi monocytes into IAV-infected lungs, but also the prevention of excessive monocyte activation by IFN-γ. Unexpectedly, type I IFNs preferentially regulate IFN-γ signaling in Ly6Clo rather than inflammatory Ly6Chi mononuclear cell populations. In the absence of type I IFN signaling, Ly6Clo monocytes/macrophages, become phenotypically and functionally more proinflammatory than Ly6Chi cells, revealing an unanticipated function of the Ly6Clo mononuclear cell subset in tissue inflammation. In addition, we show that type I IFNs employ distinct mechanisms to regulate monocyte and neutrophil trafficking. Type I IFN signaling is necessary, but not sufficient, for preventing neutrophil recruitment into the lungs of IAV-infected mice. Instead, the cooperation of type I IFNs and lymphocyte-produced IFN-γ is required to regulate the tissue neutrophilic response to IAV. Our study demonstrates that IFN interplay links innate and adaptive anti-viral immunity to orchestrate tissue inflammation and reveals an additional level of complexity for IFN-dependent regulatory mechanisms that function to prevent excessive immunopathology while preserving anti-microbial functions. PMID:26731100

  7. Thermodynamic evaluation of supercritical oxy-type power plant with high-temperature three-end membrane for air separation

    NASA Astrophysics Data System (ADS)

    Kotowicz, Janusz; Balicki, Adrian; Michalski, Sebastian

    2014-09-01

    Among the technologies which allow to reduce greenhouse gas emissions, mainly of carbon dioxide, special attention deserves the idea of `zero-emission' technology based on boilers working in oxy-combustion technology. In the paper a thermodynamic analysis of supercritical power plant fed by lignite was made. Power plant consists of: 600 MW steam power unit with live steam parameters of 650 °C/30 MPa and reheated steam parameters of 670 °C/6 MPa; circulating fluidized bed boiler working in oxy-combustion technology; air separation unit and installation of the carbon dioxide compression. Air separation unit is based on high temperature membrane working in three-end technology. Models of steam cycle, circulation fluidized bed boiler, air separation unit and carbon capture installation were made using commercial software. After integration of these models the net electricity generation efficiency as a function of the degree of oxygen recovery in high temperature membrane was analyzed.

  8. Arene Trifluoromethylation: An Effective Strategy to Obtain Air-Stable n-Type Organic Semiconductors with Tunable Optoelectronic and Electron Transfer Properties

    SciTech Connect

    Sun, Haoran; Putta, Anjaneyulu; Billion, Michael

    2012-08-02

    Modulation of organic semiconductor band gap, electron affinities (EA), ionization potentials (IP), and reorganization energies (λ) associated with charge transfer is critical for its applications. We report here that trifluoromethylation not only increases both IP and EA significantly as expected but also narrows the HOMO–LUMO band gaps and increases considerably the air-stability of arene-based n-type organic semiconductors. The increased air-stability results from relatively high EA energies and a change in oxidation mechanism. Calculated EAs and IPs show that trifluoromethylated arenes are excellent candidates for n-type semiconductor materials; though a moderate increase of inner-sphere reorganization energy (λi) associated with charge transfer is the penalty for the improved performance of the trifluoromethylated compounds. However, since λi decreases as the π conjugation increases, a rational design to produce air-stable n-type semiconductor materials with reasonably small λi is simply to prepare trifluoromethylated arenes with extended π conjugation. Finally, we found that structural isomerization can fine-tune the optoelectronic and electronic transfer properties of the corresponding aromatics.

  9. Improvement in operational characteristics of KEPCO’s line-commutation-type superconducting hybrid fault current limiter

    NASA Astrophysics Data System (ADS)

    Yim, S.-W.; Park, B.-C.; Jeong, Y.-T.; Kim, Y.-J.; Yang, S.-E.; Kim, W.-S.; Kim, H.-R.; Du, H.-I.

    2013-01-01

    A 22.9 kV class hybrid fault current limiter (FCL) developed by Korea Electric Power Corporation and LS Industrial Systems in 2006 operates using the line commutation mechanism and begins to limit the fault current after the first half-cycle. The first peak of the fault current is available for protective coordination in the power system. However, it also produces a large electromagnetic force and imposes a huge stress on power facilities such as the main transformer and gas-insulated switchgear. In this study, we improved the operational characteristics of the hybrid FCL in order to reduce the first peak of the fault current. While maintaining the structure of the hybrid FCL system, we developed a superconducting module that detects and limits the fault current during the first half-cycle. To maintain the protective coordination capacity, the hybrid FCL was designed to reduce the first peak value of the fault current by up to approximately 30%. The superconducting module was also designed to produce a minimum AC loss, generating a small, uniform magnetic field distribution during normal operation. Performance tests confirmed that when applied to the hybrid FCL, the superconducting module showed successful current limiting operation without any damage.

  10. Modified differential evolution algorithm for simple assembly line balancing with a limit on the number of machine types

    NASA Astrophysics Data System (ADS)

    Pitakaso, Rapeepan; Sethanan, Kanchana

    2016-02-01

    This article proposes the differential evolution algorithm (DE) and the modified differential evolution algorithm (DE-C) to solve a simple assembly line balancing problem type 1 (SALBP-1) and SALBP-1 when the maximum number of machine types in a workstation is considered (SALBP-1M). The proposed algorithms are tested and compared with existing effective heuristics using various sets of test instances found in the literature. The computational results show that the proposed heuristics is one of the best methods, compared with the other approaches.

  11. Effect of aviation fuel type and fuel injection conditions on the spray characteristics of pressure swirl and hybrid air blast fuel injectors

    NASA Astrophysics Data System (ADS)

    Feddema, Rick

    Feddema, Rick T. M.S.M.E., Purdue University, December 2013. Effect of Aviation Fuel Type and Fuel Injection Conditions on the Spray Characteristics of Pressure Swirl and Hybrid Air Blast Fuel Injectors. Major Professor: Dr. Paul E. Sojka, School of Mechanical Engineering Spray performance of pressure swirl and hybrid air blast fuel injectors are central to combustion stability, combustor heat management, and pollutant formation in aviation gas turbine engines. Next generation aviation gas turbine engines will optimize spray atomization characteristics of the fuel injector in order to achieve engine efficiency and emissions requirements. Fuel injector spray atomization performance is affected by the type of fuel injector, fuel liquid properties, fuel injection pressure, fuel injection temperature, and ambient pressure. Performance of pressure swirl atomizer and hybrid air blast nozzle type fuel injectors are compared in this study. Aviation jet fuels, JP-8, Jet A, JP-5, and JP-10 and their effect on fuel injector performance is investigated. Fuel injector set conditions involving fuel injector pressure, fuel temperature and ambient pressure are varied in order to compare each fuel type. One objective of this thesis is to contribute spray patternation measurements to the body of existing drop size data in the literature. Fuel droplet size tends to increase with decreasing fuel injection pressure, decreasing fuel injection temperature and increasing ambient injection pressure. The differences between fuel types at particular set conditions occur due to differences in liquid properties between fuels. Liquid viscosity and surface tension are identified to be fuel-specific properties that affect the drop size of the fuel. An open aspect of current research that this paper addresses is how much the type of aviation jet fuel affects spray atomization characteristics. Conventional aviation fuel specifications are becoming more important with new interest in alternative

  12. An essential role for TH2-type response in limiting acute tissue damage during experimental helminth infection.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Helminths induce potent Th2-type immune responses that can lead to worm expulsion, but it remains undetermined whether components of this response can enhance the wound healing responses elicited as these large multi-cellular parasites traffic thru vital tissues. We used a model of helminth infecti...

  13. Current limiters

    SciTech Connect

    Loescher, D.H.; Noren, K.

    1996-09-01

    The current that flows between the electrical test equipment and the nuclear explosive must be limited to safe levels during electrical tests conducted on nuclear explosives at the DOE Pantex facility. The safest way to limit the current is to use batteries that can provide only acceptably low current into a short circuit; unfortunately this is not always possible. When it is not possible, current limiters, along with other design features, are used to limit the current. Three types of current limiters, the fuse blower, the resistor limiter, and the MOSFET-pass-transistor limiters, are used extensively in Pantex test equipment. Detailed failure mode and effects analyses were conducted on these limiters. Two other types of limiters were also analyzed. It was found that there is no best type of limiter that should be used in all applications. The fuse blower has advantages when many circuits must be monitored, a low insertion voltage drop is important, and size and weight must be kept low. However, this limiter has many failure modes that can lead to the loss of over current protection. The resistor limiter is simple and inexpensive, but is normally usable only on circuits for which the nominal current is less than a few tens of milliamperes. The MOSFET limiter can be used on high current circuits, but it has a number of single point failure modes that can lead to a loss of protective action. Because bad component placement or poor wire routing can defeat any limiter, placement and routing must be designed carefully and documented thoroughly.

  14. Surmounting limited gene delivery into primary immune cell populations: Efficient cell type-specific adenoviral transduction by CAR.

    PubMed

    Clausen, Björn E; Brand, Anna; Karram, Khalad

    2015-06-01

    Ectopic gene expression studies in primary immune cells have been notoriously difficult to perform due to the limitations in conventional transfection and viral transduction methods. Although replication-defective adenoviruses provide an attractive alternative for gene delivery, their use has been hampered by the limited susceptibility of murine leukocytes to adenoviral infection, due to insufficient expression of the human coxsackie/adenovirus receptor (CAR). In this issue of the European Journal of Immunology, Heger et al. [Eur. J. Immunol. 2015. 45: XXXX-XXXX] report the generation of transgenic mice that enable conditional Cre/loxP-mediated expression of human CAR. The authors demonstrate that this R26/CAG-CAR∆1(StopF) mouse strain facilitates the faithful monitoring of Cre activity in situ as well as the specific and efficient adenoviral transduction of primary immune cell populations in vitro. Further tweaking of the system towards more efficient gene transfer in vivo remains a future challenge. PMID:25903647

  15. Metal-Air Batteries

    SciTech Connect

    Zhang, Jiguang; Bruce, Peter G.; Zhang, Gregory

    2011-08-01

    Metal-air batteries have much higher specific energies than most currently available primary and rechargeable batteries. Recent advances in electrode materials and electrolytes, as well as new designs on metal-air batteries, have attracted intensive effort in recent years, especially in the development of lithium-air batteries. The general principle in metal-air batteries will be reviewed in this chapter. The materials, preparation methods, and performances of metal-air batteries will be discussed. Two main metal-air batteries, Zn-air and Li-air batteries will be discussed in detail. Other type of metal-air batteries will also be described.

  16. Smac/DIABLO release from mitochondria and XIAP inhibition are essential to limit clonogenicity of Type I tumor cells after TRAIL receptor stimulation.

    PubMed

    Maas, C; Verbrugge, I; de Vries, E; Savich, G; van de Kooij, L W; Tait, S W G; Borst, J

    2010-10-01

    Death receptors, such as Fas/CD95 and TRAIL receptors, engage the extrinsic pathway for caspase activation, but also couple to the intrinsic mitochondrial route. In so-called Type II cells, death receptors require the mitochondrial pathway for apoptotic execution, whereas in Type I cells they reportedly do not. For established tumor cell lines, the Type I/Type II distinction is based on short-term apoptosis assays. We report here that the mitochondrial pathway is essential for apoptotic execution of Type I tumor cells by death receptors, when long-term clonogenicity is taken into account. A blockade of the mitochondrial pathway in Type I tumor cells - by RNA interference for Bid or Bcl-2 overexpression - reduced effector caspase activity and mediated significant clonogenic resistance to TRAIL. Downstream from the mitochondria, Caspase-9 did not contribute to clonogenic death of TRAIL-treated Type I cells. Rather, the release of Smac/DIABLO and the inhibition of XIAP activity proved to be crucial for full effector caspase activity and clonogenic execution. Thus, in Type I cells the intrinsic pathway downstream from death receptors is not redundant, but limits clonogenicity by virtue of Smac/DIABLO release and XIAP inhibition. This finding is relevant for cancer therapy using death receptor agonists. PMID:20395960

  17. Comparison of the quench and fault current limiting characteristics of the flux-coupling type SFCL with single and three-phase transformer

    NASA Astrophysics Data System (ADS)

    Jung, Byung Ik; Cho, Yong Sun; Park, Hyoung Min; Chung, Dong Chul; Choi, Hyo Sang

    2013-01-01

    The South Korean power grid has a network structure for the flexible operation of the system. The continuously increasing power demand necessitated the increase of power facilities, which decreased the impedance in the power system. As a result, the size of the fault current in the event of a system fault increased. As this increased fault current size is threatening the breaking capacity of the circuit breaker, the main protective device, a solution to this problem is needed. The superconducting fault current limiter (SFCL) has been designed to address this problem. SFCL supports the stable operation of the circuit breaker through its excellent fault-current-limiting operation [1-5]. In this paper, the quench and fault current limiting characteristics of the flux-coupling-type SFCL with one three-phase transformer were compared with those of the same SFCL type but with three single-phase transformers. In the case of the three-phase transformers, both the superconducting elements of the fault and sound phases were quenched, whereas in the case of the single-phase transformer, only that of the fault phase was quenched. For the fault current limiting rate, both cases showed similar rates for the single line-to-ground fault, but for the three-wire earth fault, the fault current limiting rate of the single-phase transformer was over 90% whereas that of the three-phase transformer was about 60%. It appears that when the three-phase transformer was used, the limiting rate decreased because the fluxes by the fault current of each phase were linked in one core. When the power loads of the superconducting elements were compared by fault type, the initial (half-cycle) load was great when the single-phase transformer was applied, whereas for the three-phase transformer, its power load was slightly lower at the initial stage but became greater after the half fault cycle.

  18. Generalized Hall-effect measurement geometries and limitations of van der Pauw-type Hall-effect measurements

    SciTech Connect

    Boerger, D.M.; Kramer, J.J.; Partain, L.D.

    1981-01-01

    A rigorous derivation is given to generalize the allowed, Hall effect, sample shapes from the restrictive, rectangular parallelepiped configurations to a much more general class of geometries characterized by mirror symmetry for materials whose mobile carriers have surfaces of constant energy in k-bar space that are well described by ellipsoids. However, this mirror symmetry condition is more restrictive than the almost arbitrary sample shapes proposed with the van der Pauw technique for thin films. Experimental data taken on n-type CdS at liquid-nitrogen temperatures in magnetic field strengths of 8 and 145 kG show that errors ranging from 1 to 600% can result from van der Pauw-type geometries depending on how much the sample shape and/or contact arrangement differs from the mirror symmetry. An empirically derived averaging technique is described that reduces the observed errors to less than 13% even with van der Pauw-type shapes that do not meet the mirror symmetry conditions.

  19. SENP1-mediated NEMO deSUMOylation in adipocytes limits inflammatory responses and type-1 diabetes progression

    PubMed Central

    Shao, Lan; Zhou, Huanjiao Jenny; Zhang, Haifeng; Qin, Lingfeng; Hwa, John; Yun, Zhong; Ji, Weidong; Min, Wang

    2015-01-01

    Adipocyte dysfunction correlates with the development of diabetes. Here we show that mice with a adipocyte-specific deletion of the SUMO-specific protease SENP1 gene develop symptoms of type-1 diabetes mellitus (T1DM), including hyperglycaemia and glucose intolerance with mild insulin resistance. Peri-pancreatic adipocytes from SENP1-deficient mice exhibit heightened NF-κB activity and production of proinflammatory cytokines, which induce CCL5 expression in adjacent pancreatic islets and direct cytotoxic effects on pancreatic islets. Mechanistic studies show that SENP1 deletion in adipocytes enhances SUMOylation of the NF-κB essential molecule, NEMO, at lysine 277/309, leading to increased NF-κB activity, cytokine production and pancreatic inflammation. We further show that NF-κB inhibitors could inhibit pre-diabetic cytokine production, β-cell damages and ameliorate the T1DM phenotype in SENP1-deficient mice. Feeding a high-fat diet augments both type-1 and type-2 diabetes phenotypes in SENP1-deficient mice, consistent with the effects on adipocyte-derived NF-κB and cytokine signalling. Our study reveals previously unrecognized mechanism regulating the onset and progression of T1DM associated with adipocyte dysfunction. PMID:26596471

  20. N-type Cu2O doped activated carbon as catalyst for improving power generation of air cathode microbial fuel cells.

    PubMed

    Zhang, Xi; Li, Kexun; Yan, Pengyu; Liu, Ziqi; Pu, Liangtao

    2015-01-01

    A novel n-type Cu2O doped activated carbon (AC) air cathode (Cu/AC) was developed as an alternative to Pt electrode for oxygen reduction in microbial fuel cells (MFCs). The maximum power density of MFCs using this novel air cathode was as high as 1390±76mWm(-2), almost 59% higher than the bare AC air cathode. Specifically, the resistance including total resistance and charge transfer resistance significantly decreased comparing to the control. Tafel curve also showed the faster electro-transfer kinetics of Cu/AC with exchange current density of 1.03×10(-3)Acm(-2), which was 69% higher than the control. Ribbon-like Cu2O was deposited on the surface of AC with the mesopore surface area increasing. Cubic Cu2O crystals exclusively expose (111) planes with the interplanar crystal spacing of 2.48Å, which was the dominate active sites for oxygen reduction reaction (ORR). N-type Cu2O with oxygen vacancies played crucial roles in electrochemical catalytic activity. PMID:25863207

  1. Study of the Tropospheric Aerosol Structure Under Changing of the Air Mass Type from Lidar Observations in Tomsk

    NASA Astrophysics Data System (ADS)

    Samoilova, S. V.; Balin, Yu. S.; Kokhanenko, G. P.; Penner, I. É.

    2016-04-01

    The aerosol optical characteristics in the main tropospheric layers are investigated based on joint interpretation of data of multi-frequency lidar sensing (110 sessions) and results of modeling of back air mass trajectories. Methodical problems for separating layers with different scattering properties and estimating their vertical boundaries are considered. Three optical criteria are simultaneously used to distinguish aerosol layers from cloud formations, including the gradient of the backscattering coefficient, optical depth, and the depolarization ratio. High values of the lidar ratio (66 sr) and of the Angstrom exponent (1.62) in the shortwavelength spectral range are observed in the boundary layer for Arctic transport. At the same time, low values of these optical parameters are characteristic for Asian transport: the lidar ratio is 54 sr and the Angstrom exponent is 1.1, which is explained by different relative contributions of the coarse and fine aerosol fractions to the air mass.

  2. Stability of polycyclic aromatic compounds in polyurethane foam-type passive air samplers upon O3 exposure

    NASA Astrophysics Data System (ADS)

    Jariyasopit, Narumol; Liu, Yongchun; Liggio, John; Harner, Tom

    2015-11-01

    Stability of polycyclic aromatic compounds (PACs) in polyurethane foam (PUF) disks upon O3 exposure was studied in a flow tube. A wide range of PACs was evaluated by spiking PUF disks with PACs and exposing to O3 at concentrations that were equivalent to two months exposure, a typical deployment period for these passive air samplers. Ambient concentrations of O3 (∼50 ppb) at 0% and 50% relative humidity (RH) were applied. At 0% RH, 23 of 68 PACs yielded more than 50% loss after exposure. The mean percent loss was 30% with perylene and 9,10-dimethylanthracene the most reactive polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs, respectively. At 50% RH, 77% of the studied PACs was stable upon O3 exposure (PACexposed/PACunexposed > 0.7). The mean percent loss was 17% and only 7 of 68 PACs yielded greater than 50% loss. In general, the reactivity of most of the PACs decreased at higher RH, except for the reactive PAHs (acenaphthylene, 2,3-dimethylanthracene, 9,10-dimethylanthracene, dibenzothiophene, and 2-methyldibenzothiophene) which demonstrated lower RH dependence. The experimental conditions in this study represent a worst case scenario for the stability of PACs sorbed to PUF. In reality, the sampling of PACs in ambient air represents an 'aged' component of PACs where the most reactive species have already partially been removed. Also, PACs in ambient air will be associated with the particle phase to varying extents that will help to enhance their stability. Therefore, under regular operating conditions, over a 2-month exposure, we expect a minimal error in the measurement of total concentration of PACs in air using the PUF disk passive sampler.

  3. Formation Mechanism of SiO2-Type Inclusions in Si-Mn-Killed Steel Wires Containing Limited Aluminum Content

    NASA Astrophysics Data System (ADS)

    Wang, Kunpeng; Jiang, Min; Wang, Xinhua; Wang, Ying; Zhao, Haoqian; Cao, Zhanmin

    2015-10-01

    The origin, formation mechanism, and evolution of SiO2-type inclusions in Si-Mn-killed steel wires were studied by pilot trials with systematical samplings at the refining ladle, casting tundish, as-cast bloom, reheated bloom, and hot-rolled rods. It was found that the inclusions in tundish were well controlled in the low melting point region. By contrast, MnO-SiO2-Al2O3 inclusions in the as-cast bloom were with compositions located in the primary region of SiO2, and most CaO-SiO2-Al2O3-MnO inclusions lied in primary phase region of anorthite. Therefore, precipitation of SiO2 particles in MnO-SiO2-Al2O3 inclusions can be easier than in CaO-SiO2-Al2O3-MnO inclusions to form dual-phase inclusions in the as-cast bloom. Thermodynamic calculation by the software FactSage 6.4 (CRCT-ThermFact Inc., Montréal, Canada) showed that mass transfer between liquid steel and inclusions resulted in the rise of SiO2 content in inclusions from tundish to as-cast bloom and accelerated the precipitation of pure SiO2 phase in the formed MnO-SiO2-Al2O3 inclusions. As a result, the inclusions characterized by dual-phase structure of pure SiO2 in MnO-SiO2-Al2O3 matrix were observed in both as-cast and reheated blooms. Moreover, the ratio of such dual-phase SiO2-type inclusions witnessed an obvious increase from 0 to 25.4 pct before and after casting, whereas it changed little during the reheating and rolling. Therefore, it can be reasonably concluded that they were mainly formed during casting. Comparing the evolution of the inclusions composition and morphology in as-cast bloom and rolled products, a formation mechanism of the SiO2-type inclusions in wire rods was proposed, which included (1) precipitation of SiO2 in the formed MnO-SiO2-Al2O3 inclusion during casting and (2) solid-phase separation of the undeformed SiO2 precipitation from its softer MnO-SiO2-Al2O3 matrix during multipass rolling.

  4. Discovery of a companion at the brown dwarf limit to the solar-type star Gliese 29

    NASA Astrophysics Data System (ADS)

    Chini, R.; Fuhrmann, K.; Pozo Nuñez, F.; Ramolla, M.; Kaderhandt, L.; Niedworok, N.; Hodapp, K.-W.

    2016-07-01

    Gliese 29 is a 7 to 8 Gyr old, southern Population I turnoff star with a large proper motion of 1 arcsec/yr. Using recent direct imaging observations with the 0.8 m Infrared Imaging System (IRIS) of the Universitätssternwarte Bochum near Cerro Armazones in Chile, we demonstrate that the faint source 2MASS J00402651-5927168 at a projected angular separation ρ=6.35 arcsec is a common-proper-motion companion to Gl 29. Provided this source is not part of a further subsystem, the IRIS J- and K_s-band photometry either implies a spectral type of about L2, based on its absolute magnitude, or an approximate mass M_B ≃ 0.077 M⊙, suggesting that it may even be a brown dwarf. Assuming a face-on circular orbit this faint companion orbits Gl 29 in 1880 years.

  5. GPRC6A mediates Alum-induced Nlrp3 inflammasome activation but limits Th2 type antibody responses

    PubMed Central

    Quandt, Dagmar; Rothe, Kathrin; Baerwald, Christoph; Rossol, Manuela

    2015-01-01

    Alum adjuvanticity is still an unknown mechanism despite the frequent use as vaccine adjuvant in humans. Here we show that Alum-induced inflammasome activation in vitro and in vivo is mediated by the G protein-coupled receptor GPRC6A. The Alum-induced humoral response in vivo was independent of the inflammasome because Nlrp3−/− and ASC−/− mice responded normally to Alum and blockade of IL-1 had no effect on antibody production. In contrast, Alum adjuvanticity was increased in GPRC6A−/− mice resulting in increased antibody responses and increased Th2 cytokine concentrations compared to wildtype mice. In vitro activation of GPRC6A−/− splenic B cells also induced increased IgG1 concentrations compared to wildtype B cells. For the first time, we show GPRC6A expression in B cells, contributing to the direct effects of Alum on those cells. B cell produced immunostimulatory IL-10 is elevated in GPRC6A−/− B cells in vitro and in vivo. Our results demonstrate a dual role of GPRC6A in Alum adjuvanticity. GPCR6A activation by Alum leads to the initiation of innate inflammatory responses whereas it is an important signal for the limitation of adaptive immune responses induced by Alum, partially explained by B cell IL-10. PMID:26602597

  6. Obtaining molecular hydrogen in electric discharge of the tornado type in air mixture with ethanol and water vapors

    NASA Astrophysics Data System (ADS)

    Levko, D. S.; Shchedrin, A. I.; Chernyak, V. Ya.; Ol'Shevskiĭ, S. V.; Nedybalyuk, O. A.

    2010-11-01

    A new plasmachemical reactor is proposed that provides a high yield of hydrogen from electric discharge in a mixture of air with ethanol and water vapors. It is shown that intense electron-molecule reactions and high temperature in the discharge region favor an increase in the degree of H2O and C2H5OH conversion into molecular hydrogen. A mechanism of the initiation of chain reactions leading to H2 formation is determined. It is established that H2 concentration reaches saturation in the region of discharge currents above 200 mA.

  7. Primary zone air proportioner

    DOEpatents

    Cleary, Edward N. G.

    1982-10-12

    An air proportioner is provided for a liquid hydrocarbon fueled gas turbine of the type which is convertible to oil gas fuel and to coal gas fuel. The turbine includes a shell for enclosing the turbine, an air duct for venting air in said shell to a gasifier, and a fuel injector for injecting gasified fuel into the turbine. The air proportioner comprises a second air duct for venting air from the air duct for mixing with fuel from the gasifier. The air can be directly injected into the gas combustion basket along with the fuel from the injector or premixed with fuel from the gasifier prior to injection by the fuel injector.

  8. Too much of a good thing: Sustained type 1 interferon signaling limits humoral responses to secondary viral infection.

    PubMed

    Teijaro, John R

    2016-02-01

    The induction of a pan-immunosuppressive state is a central feature of persistent viral infections. Over the past decade, multiple pathways have been identified that contribute to immune suppression. Recently, it was revealed that aberrant or sustained type 1 interferon (IFN-I) production or signaling is a central contributor to immune suppression elicited during persistent viral infection. In this issue, Honke et al. [Eur. J. Immunol. 2016. 46: 372-380] identify that IFN-I signaling promotes an immune suppressive state during persistent lymphocytic choriomeningitis virus infection by inhibiting enforced virus replication in CD169(+) macrophages. The authors demonstrate that mice infected with a persistent strain of lymphocytic choriomeningitis virus have blunted humoral immune responses to a superinfecting vesicular stomatitis virus infection. The absence of virus replication in CD169(+) macrophages was not due to antiviral CD8(+) T cell-mediated killing of CD169(+) macrophages, but required sustained IFN-I responses. In turn, reduction in vesicular stomatitis virus replication in CD169(+) macrophages resulted in a reduction in antigen production, which is necessary for generating optimal humoral responses. This study highlights a novel mechanism by which IFN-I signaling promotes an immune suppressive state during persistent viral infection. PMID:26783074

  9. HCMM/soil moisture experiment. [relationship between surface minus air temperature differential and available water according to crop type in Canada

    NASA Technical Reports Server (NTRS)

    Cihlar, J. (Principal Investigator)

    1980-01-01

    Progress in the compilation and analysis of airborne and ground data to determine the relationship between the maximum surface minus maximum air temperature differential (delta Tsa) and available water (PAW) is reported. Also, results of an analysis of HCMM images to determine the effect of cloud cover on the availability of HCMM-type data are presented. An inverse relationship between delta Tsa and PAW is indicated along with stable delta Tsa vs. PAW distributions for fully developed canopies. Large variations, both geographical and diurnal, in the cloud cover images are reported. The average monthly daytime cloud cover fluctuated between 40 and 60 percent.

  10. The impact of fatigue in air medical and other types of operations: a review of fatigue facts and potential countermeasures.

    PubMed

    Caldwell, J A

    2001-01-01

    Because of its effects on productivity and safety, fatigue is receiving increasing attention in a variety of settings, including aviation. Fatigue-related problems cost America an estimated $18 billion a year in terms of lost productivity, and fatigue-related drowsiness on the highways contributes to more than 1500 fatalities, 100,000 crashes, and 76,000 injuries annually. Furthermore, evidence is mounting that pilot and aircrew fatigue has been a causative factor in several aviation mishaps. Although substantial research has been conducted on the nature of fatigue and the effectiveness of various countermeasures, much of the relevant information may not be reaching those who need it most. The importance of obtaining adequate daily sleep and the efficacy of proper work/rest schedules, strategic napping, rest breaks, circadian-entrainment interventions, and other techniques should be emphasized in air medical training programs along with the more standard courses aimed at maintaining crew skills and improving flight safety. Once the facts are known, the aircrew's ability to control fatigue will enhance the productivity and safety of air ambulance operations. PMID:11182702

  11. Backstepping sliding mode tracking control of a vane-type air motor X-Y table motion system.

    PubMed

    Lu, Chia-Hua; Hwang, Yean-Ren; Shen, Yu-Ta

    2011-04-01

    Air motors are increasingly being used in pneumatic related industries because of their advantages of low operating cost and low maintenance. The DSP controller and the backstepping sliding mode control method were utilized in this study to control an X-Y pneumatic table for tracking trajectory. Due to the effects of the compressibility of air, friction between the motor and ball screw table and the dead-zone effect caused by the proportional valve, the system will yield different responses even with the same inlet pressure and will chatter at low speed. Hence under certain conditions, this method of backstepping sliding mode control can be applied to achieve better results than with the PID controller, such as for tracking circle error and tracking error of the two axes. According to the results, a steady-state error of 0.5 μm can be achieved. The proposed method of backstepping sliding mode control can accomplish accurate tracking circle trajectory performance, offering an improvement in the tracking error of more than 50% over that of the PID controller. PMID:21272879

  12. A systematic review of air pollution as a risk factor for cardiovascular disease in South Asia: limited evidence from India and Pakistan.

    PubMed

    Yamamoto, S S; Phalkey, R; Malik, A A

    2014-03-01

    Cardiovascular diseases (CVD) are major contributors to mortality and morbidity in South Asia. Chronic exposure to air pollution is an important risk factor for cardiovascular diseases, although the majority of studies to date have been conducted in developed countries. Both indoor and outdoor air pollution are growing problems in developing countries in South Asia yet the impact on rising rates of CVD in these regions has largely been ignored. We aimed to assess the evidence available regarding air pollution effects on CVD and CVD risk factors in lower income countries in South Asia. A literature search was conducted in PubMed and Web of Science. Our inclusion criteria included peer-reviewed, original, empirical articles published in English between the years 1990 and 2012, conducted in the World Bank South Asia region (Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan and Sri Lanka). This resulted in 30 articles. Nine articles met our inclusion criteria and were assessed for this systematic review. Most of the studies were cross-sectional and examined measured particulate matter effects on CVD outcomes and indicators. We observed a bias as nearly all of the studies were from India. Hypertension and CVD deaths were positively associated with higher particulate matter levels. Biomarkers of oxidative stress such as increased levels of P-selection expressing platelets, depleted superoxide dismutase and reactive oxygen species generation as well as elevated levels of inflammatory-related C-reactive protein, interleukin-6 and interleukin-8 were also positively associated with biomass use or elevated particulate matter levels. An important outcome of this investigation was the evidence suggesting important air pollution effects regarding CVD risk in South Asia. However, too few studies have been conducted. There is as an urgent need for longer term investigations using robust measures of air pollution with different population groups that include a wider

  13. Temperature Dependence and High-Temperature Stability of the Annealed Ni/Au Ohmic Contact to p-Type GaN in Air

    NASA Astrophysics Data System (ADS)

    Zhao, Shirong; McFavilen, Heather; Wang, Shuo; Ponce, Fernando A.; Arena, Chantal; Goodnick, Stephen; Chowdhury, Srabanti

    2016-04-01

    We report on the temperature-dependent contact resistivity and high-temperature stability of the annealed Ni/Au ohmic contacts to p-type GaN in air. As the measure temperature increases from 25°C to 390°C, both the specific contact resistivity (ρ c) and sheet resistance (R sh) decrease by factors ˜10, contributing to the 10-fold increase in current at 390°C compared with that at 25°C. It was also observed that the ρ c was further reduced by 36%, i.e., from 2.2 × 10-3 Ω cm2 to 1.4 × 10-3 Ω cm2, during the 48-h high-temperature stability test at 450°C in air, showing excellent stability of the contacts. An increase in ρ c was observed after the contacts were subjected to 500°C in air. Higher temperature stress led to a significant increase in ρ c. The contacts show rectifying I-V characteristics after being subjected to 700°C for 1 h. The degradation mechanics were analyzed with the assistance of transmission electron microscopy and energy dispersive x-ray spectroscopy.

  14. Changes in the dynamics of foliar N metabolites in oak saplings by drought and air warming depend on species and soil type.

    PubMed

    Hu, Bin; Simon, Judy; Günthardt-Goerg, Madeleine S; Arend, Matthias; Kuster, Thomas M; Rennenberg, Heinz

    2015-01-01

    Climate change poses direct or indirect influences on physiological mechanisms in plants. In particular, long living plants like trees have to cope with the predicted climate changes (i.e. drought and air warming) during their life span. The present study aimed to quantify the consequences of simulated climate change for foliar N metabolites over a drought-rewetting-drought course. Saplings of three Central European oak species (i.e. Quercus robur, Q. petraea, Q. pubescens) were tested on two different soil types (i.e. acidic and calcareous). Consecutive drought periods increased foliar amino acid-N and soluble protein-N concentrations at the expense of structural N in all three oak species. In addition, transient effects on foliar metabolite dynamics were observed over the drought-rewetting-drought course. The lowest levels of foliar soluble protein-N, amino acid-N and potassium cation with a minor response to drought and air warming were found in the oak species originating from the driest/warmest habitat (Q. pubescens) compared to Q. robur and Q. petraea. Higher foliar osmolyte-N and potassium under drought and air warming were observed in all oak species when grown on calcareous versus acidic soil. These results indicate that species-specific differences in physiological mechanisms to compensate drought and elevated temperature are modified by soil acidity. PMID:25961713

  15. Changes in the Dynamics of Foliar N Metabolites in Oak Saplings by Drought and Air Warming Depend on Species and Soil Type

    PubMed Central

    Hu, Bin; Simon, Judy; Günthardt-Goerg, Madeleine S.; Arend, Matthias; Kuster, Thomas M.; Rennenberg, Heinz

    2015-01-01

    Climate change poses direct or indirect influences on physiological mechanisms in plants. In particular, long living plants like trees have to cope with the predicted climate changes (i.e. drought and air warming) during their life span. The present study aimed to quantify the consequences of simulated climate change for foliar N metabolites over a drought-rewetting-drought course. Saplings of three Central European oak species (i.e. Quercus robur, Q. petraea, Q. pubescens) were tested on two different soil types (i.e. acidic and calcareous). Consecutive drought periods increased foliar amino acid-N and soluble protein-N concentrations at the expense of structural N in all three oak species. In addition, transient effects on foliar metabolite dynamics were observed over the drought-rewetting-drought course. The lowest levels of foliar soluble protein-N, amino acid-N and potassium cation with a minor response to drought and air warming were found in the oak species originating from the driest/warmest habitat (Q. pubescens) compared to Q. robur and Q. petraea. Higher foliar osmolyte-N and potassium under drought and air warming were observed in all oak species when grown on calcareous versus acidic soil. These results indicate that species-specific differences in physiological mechanisms to compensate drought and elevated temperature are modified by soil acidity. PMID:25961713

  16. Applicability and limitations of enzyme addition assays for the characterisation of soil organic phosphorus across a range of soil types

    NASA Astrophysics Data System (ADS)

    Jarosch, Klaus; Doolette, Ashlea; Smernik, Ronald; Frossard, Emmanuel; Bünemann, Else K.

    2014-05-01

    Solution 31P NMR spectroscopy is a powerful tool for the characterisation and quantification of organic P classes in soil. Potential limitations are due to costs, equipment accessibility and the requirement of relatively large amounts of sample. A recent alternative approach for the quantification of specific organic P classes is the use of substrate-specific phosphohydrolase enzymes which cleave the inorganic orthophosphate from the organic moiety. The released orthophosphate is detectable by colorimetry. Conclusions about the hydrolysed class of organic P can be made based on the comparison of inorganic P concentrations in enzymatically treated and untreated samples. The aim of this study was to test the applicability of enzyme addition assays for the characterisation of organic P classes on a) NaOH-EDTA extracts, b) soil:water filtrates (0.2 μm) and c) soil:water suspensions. The organic P classes in NaOH-EDTA extracts were also determined by 31P NMR spectroscopy, enabling a comparison between methods. Ten topsoil samples from four continents (five cambisols, two ferralsols, two luvisols and one lixisol) with varying total P content (83 - 1,1560 mg kg-1), pHH2O (4.2 - 8.0) and land management (grassland or cropped land) were analysed. Four different classes of organic P were determined by the enzyme addition assay: 1) monoester like-P (by an acid phosphatase known to hydrolyse simple monoesters, pyrophosphate and ATP), 2) DNA-like P (by a nuclease in combination with an acid phosphatase), 3) inositol phosphate-like P (by a phytase known to hydrolyse all monoester like-P plus myo-inositol hexakisphosphate and scyllo-inositol hexakisphosphate) and 4) enzyme stable-P (enzymatically not hydrolysed organic P forms). In the ten topsoil samples, NaOH-EDTA-extractable organic P ranged from 6 - 1,115 mg P kg-1 soil. Of this, 33 - 92 % was enzyme labile, with inositol phosphate-like P being the largest organic P class in most soils (15 - 51%), followed by monoester

  17. BAERLIN2014 - the influence of land surface types on and the horizontal heterogeneity of air pollutant levels in Berlin

    NASA Astrophysics Data System (ADS)

    Bonn, Boris; von Schneidemesser, Erika; Andrich, Dorota; Quedenau, Jörn; Gerwig, Holger; Lüdecke, Anja; Kura, Jürgen; Pietsch, Axel; Ehlers, Christian; Klemp, Dieter; Kofahl, Claudia; Nothard, Rainer; Kerschbaumer, Andreas; Junkermann, Wolfgang; Grote, Rüdiger; Pohl, Tobias; Weber, Konradin; Lode, Birgit; Schönberger, Philipp; Churkina, Galina; Butler, Tim M.; Lawrence, Mark G.

    2016-06-01

    Urban air quality and human health are among the key aspects of future urban planning. In order to address pollutants such as ozone and particulate matter, efforts need to be made to quantify and reduce their concentrations. One important aspect in understanding urban air quality is the influence of urban vegetation which may act as both emitter and sink for trace gases and aerosol particles. In this context, the "Berlin Air quality and Ecosystem Research: Local and long-range Impact of anthropogenic and Natural hydrocarbons 2014" (BAERLIN2014) campaign was conducted between 2 June and 29 August in the metropolitan area of Berlin and Brandenburg, Germany. The predominant goals of the campaign were (1) the characterization of urban gaseous and particulate pollution and its attribution to anthropogenic and natural sources in the region of interest, especially considering the connection between biogenic volatile organic compounds and particulates and ozone; (2) the quantification of the impact of urban vegetation on organic trace gas levels and the presence of oxidants such as ozone; and (3) to explain the local heterogeneity of pollutants by defining the distribution of sources and sinks relevant for the interpretation of model simulations. In order to do so, the campaign included stationary measurements at urban background station and mobile observations carried out from bicycle, van and airborne platforms. This paper provides an overview of the mobile measurements (Mobile BAERLIN2014) and general conclusions drawn from the analysis. Bicycle measurements showed micro-scale variations of temperature and particulate matter, displaying a substantial reduction of mean temperatures and particulate levels in the proximity of vegetated areas compared to typical urban residential area (background) measurements. Van measurements extended the area covered by bicycle observations and included continuous measurements of O3, NOx, CO, CO2 and point-wise measurement of volatile

  18. [Characteristics of aerosol water-soluble inorganic ions in three types air-pollution incidents of Nanjing City].

    PubMed

    Zhang, Qiu-Chen; Zhu, Bin; Su, Ji-Feng; Wang, Hong-Lei

    2012-06-01

    In order to compare aerosol water-soluble inorganic species in different air-pollution periods, samples of PM10, PM2.1, PM1.1 and the main water-soluble ions (NH4+, Mg2+, Ca2+, Na+, K+, NO2(-), F(-), NO3(-), Cl(-), SO4(2-)) were measured, which were from 3 air-pollution incidents (continued pollution in October 16-30 of 2009, sandstorm pollution in April 27-30 of 2010, and crop burning pollution in June 14 of 2010. The results show that aerosol pollution of 3 periods is serious. The lowest PM2.1/PM10 is only 0.27, which is from sandstorm pollution period, while the largest is 0. 7 from crop burning pollution period. In continued pollution periods, NO3(-) and SO4(2-) are the dominant ions, and the total anions account for an average of 18.62%, 32.92% and 33.53% of PM10, PM2.1 and PM1.1. Total water-soluble ions only account for 13.36%, 23.72% and 28.54% of PM10, PM2.1 and PM1.1 due to the insoluble species is increased in sandstorm pollution period. The mass concentration of Ca2+ in sandstorm pollution period is higher than the other two pollution periods, and which is mainly in coarse particles with diameter larger than 1 microm. All the ten water-soluble ions are much higher in crop burning pollution especially K+ which is the tracer from crop burning. The peak mass concentrations of NO3(-), SO4(2-) and NH4+ are in 0.43-0.65 microm. PMID:22946180

  19. A method to assess the inter-annual weather-dependent variability in air pollution concentration and deposition based on weather typing

    NASA Astrophysics Data System (ADS)

    Pleijel, Håkan; Grundström, Maria; Karlsson, Gunilla Pihl; Karlsson, Per Erik; Chen, Deliang

    2016-02-01

    Annual anomalies in air pollutant concentrations, and deposition (bulk and throughfall) of sulphate, nitrate and ammonium, in the Gothenburg region, south-west Sweden, were correlated with optimized linear combinations of the yearly frequency of Lamb Weather Types (LWTs) to determine the extent to which the year-to-year variation in pollution exposure can be partly explained by weather related variability. Air concentrations of urban NO2, CO, PM10, as well as O3 at both an urban and a rural monitoring site, and the deposition of sulphate, nitrate and ammonium for the period 1997-2010 were included in the analysis. Linear detrending of the time series was performed to estimate trend-independent anomalies. These estimated anomalies were subtracted from observed annual values. Then the statistical significance of temporal trends with and without LWT adjustment was tested. For the pollutants studied, the annual anomaly was well correlated with the annual LWT combination (R2 in the range 0.52-0.90). Some negative (annual average [NO2], ammonia bulk deposition) or positive (average urban [O3]) temporal trends became statistically significant (p < 0.05) when the LWT adjustment was applied. In all the cases but one (NH4 throughfall, for which no temporal trend existed) the significance of temporal trends became stronger with LWT adjustment. For nitrate and ammonium, the LWT based adjustment explained a larger fraction of the inter-annual variation for bulk deposition than for throughfall. This is probably linked to the longer time scale of canopy related dry deposition processes influencing throughfall being explained to a lesser extent by LWTs than the meteorological factors controlling bulk deposition. The proposed novel methodology can be used by authorities responsible for air pollution management, and by researchers studying temporal trends in pollution, to evaluate e.g. the relative importance of changes in emissions and weather variability in annual air pollution

  20. An Air-Stripping Packed Bed Combined with a Biofilm-Type Biological Process for Treating BTEX and Total Petroleum Hydrocarbon Contaminated Groudwater

    NASA Astrophysics Data System (ADS)

    Hong, U.; Park, S.; Lim, J.; Lee, W.; Kwon, S.; Kim, Y.

    2009-12-01

    In this study, we examined the removal efficiency of a volatile compound (e.g. toluene) and a less volatile compound [e.g. total petroleum hydrocarbon (TPH)] using an air stripping packed bed combined with a biofilm-type biological process. We hypothesized that this system might be effective and economical to simultaneously remove both volatile and less volatile compounds. The gas-tight reactor has 5.9-inch-diameter and 48.8-inch-height. A spray nozzle was installed at the top cover to distribute the liquid evenly through reactor. The reactor was filled with polypropylene packing media for the increase of volatilization surface area and the growth of TPH degrading facultative aerobic bacteria on the surface of the packing media. In air stripping experiments, 45.6%, 71.7%, 72.0%, and 75.4% of toluene was removed at air injection rates of 0 L/min, 2.5 L/min, 4 L/min, and 6 L/min, respectively. Through the result, we confirmed that toluene removal efficiency increased by injecting higher amounts of air. TPH removal by stripping was minimal. To remove a less volatile TPH by commercial TPH degrading culture (BIO-ZYME B-52), 15-times diluted culture was circulated through the reactor for 2-3 days to build up a biofilm on the surface of packing media with 1 mg-soluble nitrogen source /L-water per 1 ppm of TPH. Experiments evaluating the degree of TPH biodegradation in this system are carrying out.

  1. Behavior of water balance components at sites with shallow groundwater tables: Possibilities and limitations of their simulation using different types of groundwater lysimeters

    NASA Astrophysics Data System (ADS)

    Dietrich, Ottfried; Fahle, Marcus

    2015-04-01

    Groundwater lysimeters are a special type of lysimeter that can provide valuable insights into processes occurring at sites with shallow groundwater tables. Typically, water balance simulations for such sites using hydrological models are complicated by the permanently changing directions of the water fluxes due to percolation and capillary rise and the complex hydrological conditions. Problems also arise when trying to imitate such conditions correctly in a lysimeter. The biggest challenge is to realistically simulate the lower boundary condition, which has a pronounced impact on most of the hydrological variables, especially when considering time scales shorter than one day. Historically, groundwater levels in soil monoliths of groundwater lysimeters were controlled by so-called Mariotte bottles (type 1). Even nowadays, most groundwater lysimeters use such systems. From a technical standpoint, the solution is reliable and simple to operate and maintain. Nevertheless, the accuracy of Mariotte bottles (type 1) is limited when simulatingnatural shallow groundwater table conditions which are characterized by fluctuations on a short time scale. Today's lysimeters are able to simulate measured groundwater levels with higher accuracy, even for short time steps (type 2). However, conditions in the lysimeter and the place where the reference groundwater level is measured have to be consistent in order to get reliable results. Problems also arise if the behavior of the groundwater level itself is the aim of the investigation as the groundwater level has to be pre-defined, i.e. it is the control value. A new approach regulates the lower boundary condition by controlling the in- and outflows of the lysimeter (type 3). This enlarges the field of possible applications of groundwater lysimeters, especially with respect to simulations of natural site conditions and short time scales. The presentation compares the performance of different types of groundwater lysimeters with

  2. Selection of the air heat exchanger operating in a gas turbine air bottoming cycle

    NASA Astrophysics Data System (ADS)

    Chmielniak, Tadeusz; Czaja, Daniel; Lepszy, Sebastian

    2013-12-01

    A gas turbine air bottoming cycle consists of a gas turbine unit and the air turbine part. The air part includes a compressor, air expander and air heat exchanger. The air heat exchanger couples the gas turbine to the air cycle. Due to the low specific heat of air and of the gas turbine exhaust gases, the air heat exchanger features a considerable size. The bigger the air heat exchanger, the higher its effectiveness, which results in the improvement of the efficiency of the gas turbine air bottoming cycle. On the other hand, a device with large dimensions weighs more, which may limit its use in specific locations, such as oil platforms. The thermodynamic calculations of the air heat exchanger and a preliminary selection of the device are presented. The installation used in the calculation process is a plate heat exchanger, which is characterized by a smaller size and lower values of the pressure drop compared to the shell and tube heat exchanger. Structurally, this type of the heat exchanger is quite similar to the gas turbine regenerator. The method on which the calculation procedure may be based for real installations is also presented, which have to satisfy the economic criteria of financial profitability and cost-effectiveness apart from the thermodynamic criteria.

  3. Ubiquitous Low-FeO Relict Grains in Type II Chondrules and Limited Overgrowths on Phenocrysts Following the Final Melting Event

    NASA Technical Reports Server (NTRS)

    Wasson, John T.; Rubin, Alan E.

    2006-01-01

    Type II porphyritic chondrules commonly contain several large (>40 microns) olivine phenocrysts; furnace-based cooling rates based on the assumption that these phenocrysts grew in a single-stage melting-cooling event yield chondrule cooling-rate estimates of 0.01-1 K/s. Because other evidence indicates much higher cooling rates, we examined type 11 chondrules in the CO3.0 chondrites that have experienced only minimal parent-body alteration. We discovered three kinds of evidence indicating that only minor (4-10 microns) olivine growth occurred after the final melting event: (1) Nearly all (>90%) type II chondrules in CO3.0 chondrites contain low-FeO relict grains; overgrowths on these relicts are narrow, in the range of 2-12 microns. (2) Most type II chondrules contain some FeO-rich olivine grains with decurved surfaces and acute angles between faces indicating that the grains are fragments from an earlier generation of chondrules; the limited overgrowth thicknesses following the last melting event are too thin to disguise the shard-like nature of these grains. (3) Most type II chondrules contain many small (<20 microns) euhedral or subhedral phenocrysts with central compositions that are much more ferroan than the centers of the large phenocrysts; their small sizes document the small amount of growth that occurred after the final melting event. If overgrowth thicknesses were small (4-10 microns) after the final melting event, it follows that large fractions of coarse (>40 microns) high-FeO phenocrysts are relicts from earlier generations of chondrules, and that cooling rates after the last melting event were much more rapid than indicated by models based on a single melting event. These observations are thus inconsistent with the "classic" igneous model of formation of type II porphyritic chondrules by near-total melting of a precursor mix followed by olivine nucleation on a very limited number of nuclei (say, <10) and by growth to produce the large phenocrysts

  4. Limits on Spin-independent Couplings of Light Dark Matter WIMPs with a p-type Point-contact Germanium Detector

    NASA Astrophysics Data System (ADS)

    Lin, S. T.; Wong, H. T.

    New limits on spin-independent WIMP-nucleon coupling using 39.5 kg-days of data taken with a p-type point-contact germanium detector with fiducial mass of 840 g at the Kuo-Sheng Reactor Neutrino Laboratory (KSNL) is presented. Charactering and understanding the anomalous surface behaviour is of particular significance to this study. The slow rise-time of surface events is identified via software pulse shape analysis techniques. In addition, the signal-retaining and background-rejecting efficiencies are implied to clarify the actual bulk and surface events in the mixed regime at sub-keV range. Both efficiencies are evaluated with calibration sources and a novel n-type point-contact germanium detector. Efficiencies-corrected background spectra from the low-background facility at KSNL are derived. Part of the parameter space in cross-section versus WIMP-mass is probed and excluded.

  5. Order-disorder transition in B-type Cu2ZnSnS4 and limitations of ordering through thermal treatments

    NASA Astrophysics Data System (ADS)

    Rudisch, Katharina; Ren, Yi; Platzer-Björkman, Charlotte; Scragg, Jonathan

    2016-06-01

    B-type Cu2ZnSnS4 (CZTS) thin films with varying degrees of cation order were produced and examined with resonant Raman spectroscopy. Simulations based on Vineyard's theory of order allowed kinetic analysis of the final degree of order after the applied thermal treatments. Combining the results from the simulations and the resonant Raman spectra, the kinetic parameters within the Vineyard model for the order-disorder transition in B-type CZTS were determined, as well as a method which allows quantification of the degree of order based on resonant Raman spectra. The knowledge gained about the order-disorder transition in B-type CZTS allowed the prediction of a best practice thermal treatment for high ordering. This further leads to awareness about practical limits of thermal treatments regarding the cation ordering in B-type CZTS, and suggests that such treatments are not able to produce the high cation order necessary to sufficiently reduce detrimental potential fluctuations.

  6. Effect of municipal solid waste incinerator types on characteristics of ashes from different air pollution control devices.

    PubMed

    Lu, Chien-Hsing; Chuang, Kui-Hao

    2016-01-01

    The purpose of this paper is to investigate the characteristics of fly and bottom ashes sampled from both fluidized bed (FB) and mass-burning (MB) municipal solid waste incinerators (MSWIs), respectively. Fly ashes from different locations at FB and MB MSWIs equipped with a cyclone, a semi-dry scrubber, and a bag filter as air pollution control devices were examined to provide the baseline information between physicochemical properties and leaching ability. Experimental results of leachability indicated that the bag filter fly ash (FB-FA(B)) from the FB incinerator meets Taiwan regulatory standards set through the toxicity characteristic leaching procedure. X-ray diffraction results revealed the presence of Cr5O12 and Pb2O3 in the cyclone fly ash (MB-FA(C)) and bag filter fly ash (MB-FA(B)), respectively, from the MB incinerator. To observe lead incorporation mechanism, mixture of simulate lead-laden waste with bed material were fired between 600 °C and 900 °C in a laboratory scale FB reactor. The results clearly demonstrate a substantial decrease in lead leaching ratio for products with an appropriate temperature. The concentration of Pb in the MB-FA(B) was 250 times that in the FB-FA(B), suggesting that incineration of MSW in FB is a good strategy for stabilizing hazardous metals. PMID:26226945

  7. Active (air-cooled) vs. passive (phase change material) thermal management of high power lithium-ion packs: Limitation of temperature rise and uniformity of temperature distribution

    NASA Astrophysics Data System (ADS)

    Sabbah, Rami; Kizilel, R.; Selman, J. R.; Al-Hallaj, S.

    The effectiveness of passive cooling by phase change materials (PCM) is compared with that of active (forced air) cooling. Numerical simulations were performed at different discharge rates, operating temperatures and ambient temperatures of a compact Li-ion battery pack suitable for plug-in hybrid electric vehicle (PHEV) propulsion. The results were also compared with experimental results. The PCM cooling mode uses a micro-composite graphite-PCM matrix surrounding the array of cells, while the active cooling mode uses air blown through the gaps between the cells in the same array. The results show that at stressful conditions, i.e. at high discharge rates and at high operating or ambient temperatures (for example 40-45 °C), air-cooling is not a proper thermal management system to keep the temperature of the cell in the desirable operating range without expending significant fan power. On the other hand, the passive cooling system is able to meet the operating range requirements under these same stressful conditions without the need for additional fan power.

  8. Air-sea dimethylsulfide (DMS) gas transfer in the North Atlantic: evidence for limited interfacial gas exchange at high wind speed

    NASA Astrophysics Data System (ADS)

    Bell, T. G.; De Bruyn, W.; Miller, S. D.; Ward, B.; Christensen, K.; Saltzman, E. S.

    2013-11-01

    Shipboard measurements of eddy covariance dimethylsulfide (DMS) air-sea fluxes and seawater concentration were carried out in the North Atlantic bloom region in June/July 2011. Gas transfer coefficients (k660) show a linear dependence on mean horizontal wind speed at wind speeds up to 11 m s-1. At higher wind speeds the relationship between k660 and wind speed weakens. At high winds, measured DMS fluxes were lower than predicted based on the linear relationship between wind speed and interfacial stress extrapolated from low to intermediate wind speeds. In contrast, the transfer coefficient for sensible heat did not exhibit this effect. The apparent suppression of air-sea gas flux at higher wind speeds appears to be related to sea state, as determined from shipboard wave measurements. These observations are consistent with the idea that long waves suppress near-surface water-side turbulence, and decrease interfacial gas transfer. This effect may be more easily observed for DMS than for less soluble gases, such as CO2, because the air-sea exchange of DMS is controlled by interfacial rather than bubble-mediated gas transfer under high wind speed conditions.

  9. Two reduced form air quality modeling techniques for rapidly calculating pollutant mitigation potential across many sources, locations and precursor emission types

    NASA Astrophysics Data System (ADS)

    Foley, Kristen M.; Napelenok, Sergey L.; Jang, Carey; Phillips, Sharon; Hubbell, Bryan J.; Fulcher, Charles M.

    2014-12-01

    Due to the computational cost of running regional-scale numerical air quality models, reduced form models (RFM) have been proposed as computationally efficient simulation tools for characterizing the pollutant response to many different types of emission reductions. The U.S. Environmental Protection Agency has developed two types of reduced form models based upon simulations of the Community Multiscale Air Quality (CMAQ) modeling system. One is based on statistical response surface modeling (RSM) techniques using a multidimensional kriging approach to approximate the nonlinear chemical and physical processes. The second approach is based on using sensitivity coefficients estimated with the Decoupled Direct Method in 3 dimensions (CMAQ-DDM-3D) in a Taylor series approximation for the nonlinear response of the pollutant concentrations to changes in emissions from specific sectors and locations. Both types of reduced form models are used to estimate the changes in O3 and PM2.5 across space associated with emission reductions of NOx and SO2 from power plants and other sectors in the eastern United States. This study provides a direct comparison of the RSM- and DDM-3D-based tools in terms of: computational cost, model performance against brute force runs, and model response to changes in emission inputs. For O3, the DDM-3D RFM had slightly better performance on average for low to moderate emission cuts compared to the kriging-based RSM, but over-predicted O3 disbenefits from cuts to mobile source NOx in very urban areas. The RSM approach required more up-front computational cost and produced some spurious O3 increases in response to reductions in power plant emissions. However the RSM provided more accurate predictions for PM2.5 and for predictions of very large emission cuts (e.g. -60 to -90%). This comparison indicates that there are some important differences in the output of the two approaches that should be taken under consideration when interpreting results for a

  10. Power augmentation in a Savonius-type wind-turbine by using a single air-deflecting vane

    NASA Astrophysics Data System (ADS)

    Sivapalan, S.; Sivasegaram, S.

    1982-07-01

    This paper deals with the increase of power output from a vertical-axis wind-turbine of the Savonius-type by using a single deflector vane of simple geometry. Vanes of plane and circular arc sections were used in the study. The respective influences of vane arc angle, vane size and angle of setting of the vane relative to the rotor on the power output were studied and so was the sensitivity of power output to wind direction. Power augmentation by over 50% is seen possible with a single vane of modest size. Means of further power augmentation and achievement of direction-independent operation are discussed.

  11. Interactions between cold and water limitation along a climate gradient produce sharp thresholds in ecosystem type, carbon balance, and water cycling

    NASA Astrophysics Data System (ADS)

    Kelly, A. E.; Goulden, M.; Fellows, A. W.

    2013-12-01

    California's Mediterranean climate supports a broad diversity of ecosystem types, including Sequoia forests in the mid-montane Sierra Nevada. Understanding how winter cold and summer drought interact to produce the lush forest in the Sierra is critical to predicting the impacts of projected climate change on California's ecosystems, water supply, and carbon cycling. We investigated how smooth gradients of temperature and water availability produced sharp thresholds in biomass, productivity, growing season, water use, and ultimately ecosystem type and function. We used the climate gradient of the western slope of the Sierra Nevada as a study system. Four eddy covariance towers were situated in the major ecosystem types of the Sierra Nevada at approximately 800-m elevation intervals. Eddy flux data were combined with remote sensing and direct measurements of biomass, productivity, soil available water, and evapotranspiration to understand how weather and available water control ecosystem production and function. We found that production at the high elevation lodgepole site at 2700 m was strongly limited by winter cold. Production at the low elevation oak woodland site at 400 m was strongly limited by summer drought. The yellow pine site at 1200 m was only 4 °C cooler than the oak woodland site, yet had an order of magnitude more biomass and productivity with year-round growth. The mixed conifer site at 2000 m is 3.5 °C warmer than the lodgepole forest, yet also has higher biomass, ten times higher productivity, and year-round growth. We conclude that there is a broad climatological 'sweet spot' within the Sierra Nevada, in which the Mediterranean climate can support large-statured forest with high growth rates. The range of the mid-elevation forest was sharply bounded by water limitation at the lower edge and cold limitation at the upper edge despite small differences in precipitation and temperature across these boundaries. Our results suggest that small changes

  12. Study of field-pole Bi2223 windings of air core type for a HTS propulsion motor

    NASA Astrophysics Data System (ADS)

    Sugyo, D.; Kimura, Y.; Sano, T.; Yamaguchi, K.; Izumi, M.; Miki, M.; Ohmatu, K.; Fukumoto, Y.; Fujimoto, H.

    2008-02-01

    In the present study, we designed a field pole of Bi2223 superconductor winding without iron core applied to high-temperature superconducting (HTS) motor of an axial gap type. As the preliminary step to form a field pole winding, we designed a double-pancake-coil (DPC) and qualified relationship between the terminal voltage and the excitation current. We adopted the structure of HTS winding field pole composed of stacked two layered DPC because of effective conduction cooling and electromagnetic effect. We manufactured 16 poles DPC and verified the critical current vs. terminal voltage at 77 K with liquid nitrogen. To form a rotor, 8 field-pole HTS windings were manufactured by integrating of two DPCs as a split coil. We measured the coil Ic and voltage drop of the terminal at 30 K cooled with gas-liquid mixing helium and qualified the heat generation from the coils with DC current excitation. The cooling and excitation test of the constructed field pole coils were performed in the testing motor. The results exhibit that presently developed coils possesses sufficient performance on the heat generation and the magnetic flux density in the axial-type machine under construction.

  13. Synthesis of phosphatidylcholines in ozone-exposed alveolar type II cells isolated from adult rat lung: is glycerolphosphate acyltransferase a rate-limiting enzyme

    SciTech Connect

    Haagsman, H.P.; Schuurmans, E.A.; Batenburg, J.J.; van Golde, L.M.

    1988-01-01

    Type II cells were exposed to ozone by gas diffusion through the thin Teflon bottom of culture dishes. The rate of phosphatidylcholine synthesis by type II cells, monitored by the incorporation of (Me-/sup 14/C)choline, was impaired by ozone at concentrations that did not affect other cellular parameters. The enzymes choline kinase and cholinephosphate cytidylyltransferase were not susceptible to inactivation by ozone at concentrations at which the activity of glycerolphosphate acyltransferase was decreased. The enzyme activity of lactate dehydrogenase increased after ozone exposure. The specific activity of choline kinase in the cytosolic fraction of type II cells was fivefold that in whole lung. The metabolism of (Me-/sup 14/C)choline was studied as a function of the choline concentration. Maximal rates of phosphatidylcholine synthesis were already attained at a concentration of 20 microM choline. Exposure of type II cells to ozone did not affect the recovery of label from (Me-/sup 14/C)choline in choline phosphate and CDP choline. However, the maximal rate of phosphatidylcholine synthesis decreased after ozone exposure, which indicates that the decreased apparent activity of glycerolphosphate acyltransferase limits the supply of diacylglycerols and thereby the rate of phosphatidylcholine synthesis. If the flux through the diacylglycerol pathway was stimulated by the addition of palmitic acid, a higher maximal rate of phosphatidylcholine synthesis was observed. The uptake of (Me-/sup 14/C)choline and the recovery of label in CDPcholine were not altered by the addition of different concentrations of palmitate. It is concluded that type II cells take up choline very efficiently, probably due to the high specific activity of choline kinase. At low choline concentrations the rate of phosphatidylcholine synthesis is determined by the supply of CDPcholine.

  14. Low-cycle fatigue of Type 347 stainless steel and Hastelloy alloy X in hydrogen gas and in air at elevated temperatures

    NASA Technical Reports Server (NTRS)

    Jaske, C. E.; Rice, R. C.; Buchheit, R. D.; Roach, D. B.; Porfilio, T. L.

    1976-01-01

    An investigation was conducted to assess the low-cycle fatigue resistance of two alloys, Type 347 stainless steel and Hastelloy Alloy X, that were under consideration for use in nuclear-powered rocket vehicles. Constant-amplitude, strain-controlled fatigue tests were conducted under compressive strain cycling at a constant strain rate of 0.001/sec and at total axial strain ranges of 1.5, 3.0, and 5.0 %, in both laboratory-air and low-pressure hydrogen-gas environments at temperatures from 538 to 871 C. Specimens were obtained from three heats of Type 347 stainless steel bar and two heats of Hastelloy Alloy X. The tensile properties of each heat were determined at 21, 538, 649, and 760 C. The continuous cycling fatigue resistance was determined for each heat at temperatures of 538, 760, and 871 C. The Type 347 stainless steel exhibited equal or superior fatigue resistance to the Hastelloy Alloy X at all conditions of this study.

  15. Two-dimensional model of the air flow and temperature distribution in a cavity-type heat receiver of a solar stirling engine

    SciTech Connect

    Makhkamov, K.K.; Ingham, D.B.

    1999-11-01

    A theoretical study on the air flow and temperature in the heat receiver, affected by free convection, of a Stirling Engine for a Dish/Stirling Engine Power System is presented. The standard {kappa}-{epsilon} turbulence model for the fluid flow has been used and the boundary conditions employed were obtained using a second level mathematical model of the Stirling Engine working cycle. Physical models for the distribution of the solar insolation from the Concentrator on the bottom and side walls of the cavity-type heat receiver have been taken into account. The numerical results show that most of the heat losses in the receiver are due to re-radiation from the cavity and conduction through the walls of the cavity. It is in the region of the boundary of the input window of the heat receiver where there is a sensible reduction in the temperature in the shell of the heat exchangers and this is due to the free convection of the air. Further, the numerical results show that convective heat losses increase with decreasing tilt angle.

  16. QUALITY ASSURANCE HANDBOOK FOR AIR POLLUTION MEASUREMENT SYSTEMS: VOLUME IV - METEOROLOGICAL MEASUREMENTS (REVISED - AUGUST 1994)

    EPA Science Inventory

    Procedures on installing, acceptance testing, operating, maintaining and quality assuring three types of ground-based, upper air meteorological measurement systems are described. he limitations and uncertainties in precision and accuracy measurements associated with these systems...

  17. [Growth and polysaccharide formation in Sinorhizobium meliloti strains in an air-lift-type fermentor. Effect on nodulation velocity in alfalfa plants].

    PubMed

    Lorda, G S; Castaño, R C; Pordomingo, A B; Pastor, M D; Balatti, A P

    2003-01-01

    In this paper the influence of the exopolysaccharides produced by Sinorhizobium meliloti strains on the nodulation rates in alfalfa plants has been considered. The experiments were performed in a rotary shaker and in an air-lift type fermentor. Different Sinorhizobium meliloti strains were used. Bacterial growth rates were determined by viable cell counts. Exopolysaccharide concentration was determined by precipitation with ethanol. It was observed that maximum cell concentration was in the order of 1 x 10(10) cell/ml and exopolysaccharide content was approximately 11 g/l. The experiments performed with alfalfa plants in a controlled environment chamber showed that, when inoculation was carried out with diluted suspensions (1/10), nodulation time was reduced from 10 to 4 days, while the strains retained their symbiotic properties. PMID:12920984

  18. The impact of decreases in air temperature and increases in ozone on markers of endothelial function in individuals having type-2 diabetes.

    PubMed

    Lanzinger, Stefanie; Breitner, Susanne; Neas, Lucas; Cascio, Wayne; Diaz-Sanchez, David; Hinderliter, Alan; Peters, Annette; Devlin, Robert B; Schneider, Alexandra

    2014-10-01

    Several studies have reported an association between air pollution and endothelial dysfunction, especially in individuals having diabetes. However, very few studies have examined the impact of air temperature on endothelial function. The objective of this analysis was to investigate short-term effects of temperature and ozone on endothelial function in individuals having diabetes. Moreover, we investigated interactive effects between air temperature and air pollution on markers of endothelial function. Between November 2004 and December 2005 flow-mediated dilatation (FMD), nitroglycerin-mediated dilatation (NTGMD) and several blood markers representing endothelial function were measured using brachial artery ultrasound on four consecutive days in 22 individuals with type-2 diabetes mellitus in Chapel Hill, North Carolina (USA). Daily measurements of meteorological parameters, ozone and particulate matter with an aerodynamic diameter ≤2.5 µm (PM2.5) were obtained from fixed monitoring sites. We used additive mixed-models adjusting for time trend, day of the week, relative humidity and barometric pressure to assess temperature and ozone associations with endothelial function. A 1 °C decrease in the 24-h temperature average was associated with a decrease in mean FMD on the same day (-2.2% (95%-confidence interval:[-4.7;0.3%])) and with a delay of one and four days. A temperature decrement also led to an immediate (-1.7%[-3.3;-0.04]) decrease in NTGMD. Moreover, we observed an immediate (-14.6%[-26.3;-2.9%]) and a one day delayed (-13.5%[-27.0; 0.04%]) decrease in FMD in association with a 0.01 ppm increase in the maximum 8-h moving average of ozone. Temperature effects on FMD strengthened when PM2.5 and ozone concentrations were high. The associations were similar during winter and summer. We detected an association between temperature decreases and ozone increases on endothelial dysfunction in individuals having diabetes. We conclude that endothelial dysfunction

  19. Absolute accuracy of water vapor measurements from six operational radiosonde types launched during AWEX-G and implications for AIRS validation

    NASA Astrophysics Data System (ADS)

    Miloshevich, Larry M.; VöMel, Holger; Whiteman, David N.; Lesht, Barry M.; Schmidlin, F. J.; Russo, Felicita

    2006-05-01

    A detailed assessment of radiosonde water vapor measurement accuracy throughout the tropospheric column is needed for assessing the impact of observational error on applications that use the radiosonde data as input, such as forecast modeling, radiative transfer calculations, remote sensor retrieval validation, climate trend studies, and development of climatologies and cloud and radiation parameterizations. Six operational radiosonde types were flown together in various combinations with a reference-quality hygrometer during the Atmospheric Infrared Sounder (AIRS) Water Vapor Experiment-Ground (AWEX-G), while simultaneous measurements were acquired from Raman lidar and microwave radiometers. This study determines the mean accuracy and variability of the radiosonde water vapor measurements relative to simultaneous measurements from the University of Colorado (CU) Cryogenic Frostpoint Hygrometer (CFH), a reference-quality standard of known absolute accuracy. The accuracy and performance characteristics of the following radiosonde types are evaluated: Vaisala RS80-H, RS90, and RS92; Sippican Mark IIa; Modem GL98; and the Meteolabor Snow White hygrometer. A validated correction for sensor time lag error is found to improve the accuracy and reduce the variability of upper tropospheric water vapor measurements from the Vaisala radiosondes. The AWEX data set is also used to derive and validate a new empirical correction that improves the mean calibration accuracy of Vaisala measurements by an amount that depends on the temperature, relative humidity, and sensor type. Fully corrected Vaisala radiosonde measurements are found to be suitably accurate for AIRS validation throughout the troposphere, whereas the other radiosonde types are suitably accurate under only a subset of tropospheric conditions. Although this study focuses on the accuracy of nighttime radiosonde measurements, comparison of Vaisala RS90 measurements to water vapor retrievals from a microwave radiometer

  20. Experimental Investigation of Average Heat-Transfer and Friction Coefficients for Air Flowing in Circular Tubes Having Square-Thread-Type Roughness

    NASA Technical Reports Server (NTRS)

    Sams, E. W.

    1952-01-01

    An investigation of forced-convection heat transfer and associated pressure drops was conducted with air flowing through electrically heated Inconel tubes having various degrees of square-thread-type roughness, an inside diameter of 1/2 inch, and a length of 24 inches. were obtained for tubes having conventional roughness ratios (height of thread/radius of tube) of 0 (smooth tube), 0.016, 0.025, and 0.037 over ranges of bulk Reynolds numbers up to 350,000, average inside-tube-wall temperatures up to 1950deg R, and heat-flux densities up to 115,000 Btu per hour per square foot. Data The experimental data showed that both heat transfer and friction increased with increase in surface roughness, becoming more pronounced with increase in Reynolds number; for a given roughness, both heat transfer and friction were also influenced by the tube wall-to-bulk temperature ratio. Good correlation of the heat-transfer data for all the tubes investigated was obtained by use of a modification of the conventional Nusselt correlation parameters wherein the mass velocity in the Reynolds number was replaced by the product of air density evaluated at the average film temperature and the so-called friction velocity; in addition, the physical properties of air were evaluated at the average film temperature. The isothermal friction data for the rough tubes, when plotted in the conventional manner, resulted in curves similar to those obtained by other investigators; that is, the curve for a given roughness breaks away from the Blasius line (representing turbulent flow in smooth tubes) at some value of Reynolds number, which decreases with increase in surface roughness, and then becomes a horizontal line (friction coefficient independent of Reynolds number). A comparison of the friction data for the rough tubes used herein indicated that the conventional roughness ratio is not an adequate measure of relative roughness for tubes having a square-thread-type element. The present data, as well

  1. Into Thin Air.

    ERIC Educational Resources Information Center

    Kennedy, Mike

    2001-01-01

    Shows how schools are working to avoid the types of equipment, supplies, and maintenance practices that harm indoor air quality. Simple steps to maintaining a cleaner indoor air environment are highlighted as are steps to reducing the problem air quality and the occurrence of asthma. (GR)

  2. Intratumoral spread of wild-type adenovirus is limited after local injection of human xenograft tumors: virus persists and spreads systemically at late time points.

    PubMed

    Sauthoff, Harald; Hu, Jing; Maca, Cielo; Goldman, Michael; Heitner, Sheila; Yee, Herman; Pipiya, Teona; Rom, William N; Hay, John G

    2003-03-20

    Oncolytic replicating adenoviruses are a promising new modality for the treatment of cancer. Despite the assumed biologic advantage of continued viral replication and spread from infected to uninfected cancer cells, early clinical trials demonstrate that the efficacy of current vectors is limited. In xenograft tumor models using immune-incompetent mice, wild-type adenovirus is also rarely able to eradicate established tumors. This suggests that innate immune mechanisms may clear the virus or that barriers within the tumor prevent viral spread. The aim of this study was to evaluate the kinetics of viral distribution and spread after intratumoral injection of virus in a human tumor xenograft model. After intratumoral injection of wild-type virus, high levels of titratable virus persisted within the xenograft tumors for at least 8 weeks. Virus distribution within the tumors as determined by immunohistochemistry was patchy, and virus-infected cells appeared to be flanked by tumor necrosis and connective tissue. The close proximity of virus-infected cells to the tumor-supporting structure, which is of murine origin, was clearly demonstrated using a DNA probe that specifically hybridizes to the B1 murine DNA repeat. Importantly, although virus was cleared from the circulation 6 hr after intratumoral injection, after 4 weeks systemic spread of virus was detected. In addition, vessels of infected tumors were surrounded by necrosis and an advancing rim of virus-infected tumor cells, suggesting reinfection of the xenograft tumor through the vasculature. These data suggest that human adenoviral spread within tumor xenografts is impaired by murine tumor-supporting structures. In addition, there is evidence for continued viral replication within the tumor, with subsequent systemic dissemination and reinfection of tumors via the tumor vasculature. Despite the limitations of immune-incompetent models, an understanding of the interactions between the virus and the tumor

  3. Estimation of identification limit for a small-type OSL dosimeter on the medical images by measurement of X-ray spectra.

    PubMed

    Takegami, Kazuki; Hayashi, Hiroaki; Okino, Hiroki; Kimoto, Natsumi; Maehata, Itsumi; Kanazawa, Yuki; Okazaki, Tohru; Hashizume, Takuya; Kobayashi, Ikuo

    2016-07-01

    Our aim in this study is to derive an identification limit on a dosimeter for not disturbing a medical image when patients wear a small-type optically stimulated luminescence (OSL) dosimeter on their bodies during X-ray diagnostic imaging. For evaluation of the detection limit based on an analysis of X-ray spectra, we propose a new quantitative identification method. We performed experiments for which we used diagnostic X-ray equipment, a soft-tissue-equivalent phantom (1-20 cm), and a CdTe X-ray spectrometer assuming one pixel of the X-ray imaging detector. Then, with the following two experimental settings, corresponding X-ray spectra were measured with 40-120 kVp and 0.5-1000 mAs at a source-to-detector distance of 100 cm: (1) X-rays penetrating a soft-tissue-equivalent phantom with the OSL dosimeter attached directly on the phantom, and (2) X-rays penetrating only the soft-tissue-equivalent phantom. Next, the energy fluence and errors in the fluence were calculated from the spectra. When the energy fluence with errors concerning these two experimental conditions was estimated to be indistinctive, we defined the condition as the OSL dosimeter not being identified on the X-ray image. Based on our analysis, we determined the identification limit of the dosimeter. We then compared our results with those for the general irradiation conditions used in clinics. We found that the OSL dosimeter could not be identified under the irradiation conditions of abdominal and chest radiography, namely, one can apply the OSL dosimeter to measurement of the exposure dose in the irradiation field of X-rays without disturbing medical images. PMID:27260346

  4. The development of effects-based air quality management regimes

    NASA Astrophysics Data System (ADS)

    Longhurst, J. W. S.; Irwin, J. G.; Chatterton, T. J.; Hayes, E. T.; Leksmono, N. S.; Symons, J. K.

    This paper considers the evolution of attempts to control and manage air pollution, principally but not exclusively focussing upon the challenge of managing air pollution in urban environments. The development and implementation of a range of air pollution control measures are considered. Initially the measures implemented primarily addressed point sources, a small number of fuel types and a limited number of pollutants. The adequacy of such a source-control approach is assessed within the context of a changing and challenging air pollution climate. An assessment of air quality management in the United Kingdom over a 50-year timeframe exemplifies the range of issues and challenges in contemporary air quality management. The need for new approaches is explored and the development and implementation of an effects-based, risk management system for air quality regulation is evaluated.

  5. Effects of nozzle type atmospheric dry air plasma on L929 fibroblast cells hybrid poly (ε-caprolactone)/chitosan/poly (ε-caprolactone) scaffolds interactions.

    PubMed

    Ozkan, Ozan; Turkoglu Sasmazel, Hilal

    2016-08-01

    In the study presented here, in order to improve the surface functionality and topography of poly (ε-caprolactone) (PCL)/chitosan/PCL hybrid tissue scaffolds fabricated layer by layer with electrospinning technique, an atmospheric pressure nozzle type plasma surface modification was utilized. The optimization of the plasma process parameters was carried out by monitoring the changes in surface hydrophilicity by using contact angle measurements. SEM, AFM and XPS analyses were utilized to observe the changes in topographical and chemical properties of the modified surfaces. The results showed that applied plasma modification altered the nanotopography and the functionality of the surfaces of the scaffolds. The modification applied for 9 min from a distance of 17 cm was found to provide the possible contact angle value (75.163±0.083) closest to the target value which is the value of tissue culture polystyrene (TCPS) petri dishes (∼49.7°), compared to the unmodified samples (84.46±3.86). In vitro cell culture was carried out by L929 mouse fibroblast cell line in order to examine the effects of plasma surface modification on cell-material interactions. Standard MTT assay showed improved cell viability on/within modified scaffolds confirmed with the observations of the cell attachment and the morphology by means of SEM, fluorescence and confocal imaging. The experiments performed in the study proved the enhanced biocompatibility of the nozzle type dry air plasma modified scaffolds. PMID:26906227

  6. Trends of NOx, NO2 and O3 concentrations at three different types of air quality monitoring stations in Athens, Greece

    NASA Astrophysics Data System (ADS)

    Mavroidis, I.; Ilia, M.

    2012-12-01

    This work presents a systematic analysis and evaluation of the historic and current levels of atmospheric pollution in the Athens metropolitan region, regarding nitrogen oxides (NOx = NO + NO2), ozone (O3) and the NO2/NOx and NO/NO2 concentration ratios. Hourly, daily, monthly, seasonal and annual pollutant variations are examined and compared, using the results of concentration time series from three different stations of the national network for air pollution monitoring, one urban-traffic, one urban-background and one suburban-background. Concentration data are also related to meteorological parameters. The results show that the traffic affected station of Patission Street presents the higher NOx values and the lower concentrations of O3, while it is the station with the highest number of NO2 limit exceedances. The monitoring data suggest, inter alia, that there is a change in the behaviour of the suburban-background station of Liossia at about year 2000, indicating that the exact location of this station may need to be reconsidered. Comparison of NOx concentrations in Athens with concentrations in urban areas of other countries reveal that the Patission urban-traffic station records very high NOx concentrations, while remarkably high is the ratio of NO2 concentrations recorded at the urban-traffic vs. the urban-background station in Athens, indicating the overarching role of vehicles and traffic congestion on NO2 formation. The NO2/NOx ratio in the urban-traffic station appears to be almost constant with time, while it has been increasing in other urban areas, such as London and Seoul, suggesting an increased effect of primary NO2 in these areas. Diesel passenger cars were only recently allowed in Athens and, therefore, NO2 trends should be carefully monitored since a possible increase in primary NO2 may affect compliance with NO2 air quality standards.

  7. The impact of decreases in air temperature and increases in ozone on markers of endothelial function in individuals having type-2 diabetes

    EPA Science Inventory

    Several studies have reported an association between air pollution and endothelial dysfunction, especially in individuals having diabetes. However, very few studies have examined the impact of air temperature on endothelial function. The objective of this analysis was to investig...

  8. Glutamate Limitation, BvgAS Activation, and (p)ppGpp Regulate the Expression of the Bordetella pertussis Type 3 Secretion System

    PubMed Central

    Kamachi, Kazunari; Yonezawa, Hideo; Fukutomi, Toshiyuki; Kawakami, Hayato; Kamiya, Shigeru

    2015-01-01

    ABSTRACT Bordetella pertussis is a bacterium that is considered to be highly adapted to humans, and it has not been isolated from the environment. As this bacterium does not utilize sugars, the abundant supply of glutamate in Stainer Scholte (SS) medium enables B. pertussis to grow efficiently in liquid culture in vitro, and as such, SS medium is a popular choice for laboratory experiments. However, the concentration of glutamate in the in vivo niche of B. pertussis is quite low. We investigated the bacterial response to low concentrations of glutamate to elucidate bacterial physiology via the expression of the type 3 secretion system (T3SS), and we discuss its relationship to the Bvg mode in which the two-component regulator of pathogenesis (BvgAS) is activated. Glutamate limitation induced the expression of both the T3SS apparatus and effector genes at the transcriptional level. (p)ppGpp, a modulator of the stringent response, was necessary for maximum expression of the T3SS genes. These observations indicate that the expression of the T3SS is managed by nutrient starvation. In addition, the autoaggregation ability was high in the absence of glutamate and no autoaggregation was observed in glutamate-replete medium. Taken together, glutamate-limited conditions in Bvg+ mode elicit the high expression of T3SS genes in B. pertussis and promotes its sessile form. IMPORTANCE Bordetella pertussis is a highly contagious pathogen that causes respiratory infectious disease. In spite of the increasing use of vaccination, the number of patients with pertussis is increasing. The proteins produced in vivo often are different from the protein profile under laboratory conditions; therefore, the development of conditions reflecting the host environment is important to understand native bacterial behavior. In the present study, we examined the effect of glutamate limitation, as its concentration in vivo is much lower than that in the culture medium currently used for B. pertussis

  9. Outdoor passive air monitoring of semi volatile organic compounds (SVOCs): a critical evaluation of performance and limitations of polyurethane foam (PUF) disks.

    PubMed

    Bohlin, P; Audy, O; Škrdlíková, L; Kukučka, P; Přibylová, P; Prokeš, R; Vojta, Š; Klánová, J

    2014-03-01

    The most commonly used passive air sampler (PAS) (i.e. polyurethane foam (PUF) disk) is cheap, versatile, and capable of accumulating compounds present both in gas and particle phases. Its performance for particle associated compounds is however disputable. In this study, twelve sets of triplicate PUF-PAS were deployed outdoors for exposure periods of 1-12 weeks together with continuously operated active samplers, to characterize sampling efficiency and derive sampling rates (RS) for compounds belonging to 7 SVOC classes (including particle associated compounds). PUF-PAS efficiently and consistently sampled polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), and eight novel brominated flame retardant (nBFR) compounds. Low accuracy and lack of sensitivity was observed for most polychlorinated dibenzo-p-dioxins/furans PCDD/Fs and polybrominated diphenyl ethers (PBDEs) (under the conditions of this study), with the exception of some congeners which may be used as qualitative markers for their respective classes. Application of compound specific RS was found crucial for all compounds except PCBs. Sampling efficiency of the particle associated compounds was often low. PMID:24526226

  10. Flight and Test-stand Investigation of High-performance Fuels in Modified Double-row Radial Air-cooled Engines III: Knock-limited Performance of 33-R as Compared with a Triptane Blend and 28-R in Flight

    NASA Technical Reports Server (NTRS)

    Blackman, Calvin C.; White, H. Jack

    1945-01-01

    A comparison has been made in flight of the antiknock characteristics of 33-R fuel with that of 28-R and a triptane blent. The knock-limited performance of the three fuels - 33-R, a blend of 80 percent 28-R plus 20 percent triptane (leaded to 4.5 ml TEL/gal), and 28-R - was investigated in two modified 14-cylinder double-row radial air-cooled engines. Tests were conducted on the engines as installed in the left inboard nacelle of an airplane. A carburetor-air temperature of approximately 85 deg F was maintained. The conditions covered at an engine speed of 2250 rpm were high and low blower ratios and spark advances of 25 deg and 32 deg B.T.C. For an engine speed of 1800 rpm only the high-blower condition was investigated for both 25 deg and 32 deg spark advances. For the conditions investigated the difference between 33-R and the triptane blend was found to be slight; the performance of 33-R fuel, however, was slightly higher than that of the triptane blend in the lean region. The knock-limited power obtained with the 33-R fuel was from 14 to 28 percent higher than that of the 28-R fuel for the entire range of test conditions; the greatest improvement was shown in the lean region.

  11. Air transparent soundproof window

    SciTech Connect

    Kim, Sang-Hoon; Lee, Seong-Hyun

    2014-11-15

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

  12. Limiting values of radionuclide intake and air concentration and dose conversion factors for inhalation, submersion, and ingestion: Federal guidance report No. 11

    SciTech Connect

    Eckerman, K.F.; Wolbarst, A.B.; Richardson, A.C.B.

    1988-09-01

    Radiation protection programs for workers are based, in the United States, on a hierarchy of limitations stemming from Federal guidance approved by the President. This guidance, which consists of principles, policies, and numerical primary guides, is used by Federal agencies as the basis for developing and implementing their own regulatory standards. The primary guides are usually expressed in terms of limiting doses to workers. The protection of workers against taking radioactive materials into the body, however, is accomplished largely through the use of regulations based on derived guides expressed in terms of quantities or concentrations of radionuclides. The values of these derived guides are chosen so as to assure that workers in work environments that conform to them are unlikely to receive radiation doses that exceed the primary guides. The purpose of the present report is to set forth derived guides that are consistent with current Federal radiation protection guidance. They are intended to serve as the basis for regulations setting upper bounds on the inhalation and ingestion of, and submersion in, radioactive materials in the workplace. The report also includes tables of exposure-to-dose conversion factors, for general use in assessing average individual committed doses in any population that is adequately characterized by Reference Man. 38 refs.

  13. p-i-n/n-i-p type planar hybrid structure of highly efficient perovskite solar cells towards improved air stability: synthetic strategies and the role of p-type hole transport layer (HTL) and n-type electron transport layer (ETL) metal oxides.

    PubMed

    Mali, Sawanta S; Hong, Chang Kook

    2016-05-19

    There has been fast recent progress in perovskite solar cells (PSCs) towards low cost photovoltaic technology. Organometal mixed halide (MAPbX or FAPbX) perovskites are the most promising light absorbing material sandwiched between the electron transport layer (ETL) and hole transport layer (HTL). These two layers play a critical role in boosting the power conversion efficiency (PCE) and maintaining air stability. However, the device stability is a serious issue in regular as well as p-i-n inverted type perovskite solar cells. This mini-review briefly outlines the state-of-art of p-i-n/n-i-p type planar hybrid perovskite solar cells using MAPbX/FAPbX perovskite absorbing layers. Later, we will focus on recent trends, progress and further opportunities in exploring the air stable hybrid planar structure PSCs. PMID:27161123

  14. p-i-n/n-i-p type planar hybrid structure of highly efficient perovskite solar cells towards improved air stability: synthetic strategies and the role of p-type hole transport layer (HTL) and n-type electron transport layer (ETL) metal oxides

    NASA Astrophysics Data System (ADS)

    Mali, Sawanta S.; Hong, Chang Kook

    2016-05-01

    There has been fast recent progress in perovskite solar cells (PSCs) towards low cost photovoltaic technology. Organometal mixed halide (MAPbX or FAPbX) perovskites are the most promising light absorbing material sandwiched between the electron transport layer (ETL) and hole transport layer (HTL). These two layers play a critical role in boosting the power conversion efficiency (PCE) and maintaining air stability. However, the device stability is a serious issue in regular as well as p-i-n inverted type perovskite solar cells. This mini-review briefly outlines the state-of-art of p-i-n/n-i-p type planar hybrid perovskite solar cells using MAPbX/FAPbX perovskite absorbing layers. Later, we will focus on recent trends, progress and further opportunities in exploring the air stable hybrid planar structure PSCs.

  15. The MASSIVE survey. I. A volume-limited integral-field spectroscopic study of the most massive early-type galaxies within 108 Mpc

    SciTech Connect

    Ma, Chung-Pei; Greene, Jenny E.; Murphy, Jeremy D.; McConnell, Nicholas; Janish, Ryan; Blakeslee, John P.; Thomas, Jens

    2014-11-10

    Massive early-type galaxies represent the modern day remnants of the earliest major star formation episodes in the history of the universe. These galaxies are central to our understanding of the evolution of cosmic structure, stellar populations, and supermassive black holes, but the details of their complex formation histories remain uncertain. To address this situation, we have initiated the MASSIVE Survey, a volume-limited, multi-wavelength, integral-field spectroscopic (IFS) and photometric survey of the structure and dynamics of the ∼100 most massive early-type galaxies within a distance of 108 Mpc. This survey probes a stellar mass range M* ≳ 10{sup 11.5} M {sub ☉} and diverse galaxy environments that have not been systematically studied to date. Our wide-field IFS data cover about two effective radii of individual galaxies, and for a subset of them, we are acquiring additional IFS observations on sub-arcsecond scales with adaptive optics. We are also acquiring deep K-band imaging to trace the extended halos of the galaxies and measure accurate total magnitudes. Dynamical orbit modeling of the combined data will allow us to simultaneously determine the stellar, black hole, and dark matter halo masses. The primary goals of the project are to constrain the black hole scaling relations at high masses, investigate systematically the stellar initial mass function and dark matter distribution in massive galaxies, and probe the late-time assembly of ellipticals through stellar population and kinematical gradients. In this paper, we describe the MASSIVE sample selection, discuss the distinct demographics and structural and environmental properties of the selected galaxies, and provide an overview of our basic observational program, science goals and early survey results.

  16. Phosphate Homeostasis in Conditions of Phosphate Proficiency and Limitation in the Wild Type and the phoP Mutant of Streptomyces lividans

    PubMed Central

    Prigent, Magali; Holland, Ian Barry; Virolle, Marie-Joelle

    2015-01-01

    Phosphate, as a constituent of the high energy molecules, ATP/GTP and polyphosphate, plays a crucial role in most of the metabolic processes of living organisms. Therefore, the adaptation to low Pi availability is a major challenge for bacteria. In Streptomyces, this adaptation is tightly controlled by the two component PhoR/PhoP system. In this study, the free intracellular Pi, ATP, ADP and polyP content of the wild type and the phoP mutant strain of S. lividans TK24 were analyzed at discrete time points throughout growth in Pi replete and limited media. PolyP length and content was shown to be directly related to the Pi content of the growth medium. In Pi repletion, ATP and high molecular weight (HMW) polyP contents were higher in the phoP mutant than in the WT strain. This supports the recently proposed repressive effect of PhoP on oxidative phosphorylation. High oxidative phosphorylation activity might also have a direct or indirect positive impact on HMW polyP synthesis. In Pi sufficiency as in Pi limitation, the degradation of these polymers was shown to be clearly delayed in the phoP mutant, indicating PhoP dependent expression of the enzymes involved in this degradation. The efficient storage of Pi as polyphosphate and/or its inefficient degradation in Pi in the phoP mutant resulted in low levels of free Pi and ATP that are likely to be, at least in part, responsible for the very poor growth of this mutant in Pi limitation. Furthermore, short polyP was shown to be present outside the cell, tightly bound to the mycelium via electrostatic interactions involving divalent cations. Less short polyP was found to be associated with the mycelium of the phoP mutant than with that of the WT strain, indicating that generation and externalization of these short polyP molecules was directly or indirectly dependent on PhoP. PMID:25978423

  17. Cardiac Parasympathetic Reactivation in Elite Soccer Players During Different Types of Traditional High-Intensity Training Exercise Modes and Specific Tests: Interests and Limits

    PubMed Central

    Dellal, Alexandre; Casamichana, David; Castellano, Julen; Haddad, Monoem; Moalla, Wassim; Chamari, Karim

    2015-01-01

    Background: The cardiac parasympathetic reactivation is currently used in soccer with a daily or weekly monitoring. However, previous studies have not investigated how this cardiac parasympathetic reactivation is in elite soccer players along different types of traditional high-intensity training exercise and specific tests. In this context, the present study aim to analyse it and to determine the interests and limits of this type of physiological information. Objectives: The present study aims to examine how different traditional training exercise modes affect the cardiac parasympathetic reactivation function in elite soccer players. Materials and Methods: Twenty-two international soccer players participating in UEFA Champion’s League took part in this study (age: 24.3 ± 4.2 years; height: 178.1 ± 6.2 cm; body mass: 80.3 ± 5.7 kg). Players performed different training methods including: short-duration intermittent exercises (INT) in-line and with changes of direction (COD) (10 - 10 seconds, 15 - 15 seconds, 30 - 30 seconds, e.g. an alternance of 10 - 10 seconds is 10 seconds of running according to the maximal aerobic speed (MAS) and 10-sec of recovery), INT including agility and technical skills (8 - 24-seconds), small-sided-games (SSGs) with and without goalkeepers (2 vs. 2, 3 vs. 3, 4 vs. 4), and repeated sprint ability (RSA) efforts (10 × 20 m, 10 × 30 m, 15 × 20 m). Heart rate (HR) decline was recorded 3 minutes after each exercise. Results: HR declines were greater after the RSA compared to SSGs (P < 0.001) and INT (P < 0.01), especially at 1 min post-exercise. In addition, when the analysis focused on each type of exercise, greater HR declines were observed in on-field players at 1 minute when there was: inclusion of goalkeepers in SSGs (for 2 vs. 2 and 3 vs. 3, P < 0.01); increase of sprint distances or number of sprint repetitions in RSA (P < 0.01); increase of intensity (% of maximal aerobic speed), and the use of COD or inclusion of technical

  18. Hα imaging of the Herschel Reference Survey. The star formation properties of a volume-limited, K-band-selected sample of nearby late-type galaxies

    NASA Astrophysics Data System (ADS)

    Boselli, A.; Fossati, M.; Gavazzi, G.; Ciesla, L.; Buat, V.; Boissier, S.; Hughes, T. M.

    2015-07-01

    We present new Hα+[NII] imaging data of late-type galaxies in the Herschel Reference Survey aimed at studying the star formation properties of a K-band-selected, volume-limited sample of nearby galaxies. The Hα+[NII] data are corrected for [NII] contamination and dust attenuation using different recipes based on the Balmer decrement and the 24 μm luminosities. We show that the Hα luminosities derived with different corrections give consistent results only whenever the uncertainty on the estimate of the Balmer decrement is σ [C(Hβ)] ≤ 0.1. We used these data to derive the star formation rate of the late-type galaxies of the sample and compare these estimates to those determined using independent monochromatic tracers (far-UV, radio continuum) or the output of spectral energy distribution (SED) fitting codes. This comparison suggests that the 24 μm based dust extinction correction for the Hα data might not be universal and that it should be used with caution in all objects with a low star formation activity, where dust heating can be dominated by the old stellar population. Furthermore, because of the sudden truncation of the star formation activity of cluster galaxies occurring after their interaction with the surrounding environment, the stationarity conditions required to transform monochromatic fluxes into star formation rates might not always be satisfied in tracers other than the Hα luminosity. In a similar way, the parametrisation of the star formation history generally used in SED fitting codes might not be adequate for these recently interacting systems. We then use the derived star formation rates to study the star formation rate luminosity distribution and the typical scaling relations of the late-type galaxies of the HRS. We observe a systematic decrease of the specific star formation rate with increasing stellar mass, stellar mass surface density, and metallicity. We also observe an increase of the asymmetry and smoothness parameters measured

  19. A review of air exchange rate models for air pollution exposure assessments.

    PubMed

    Breen, Michael S; Schultz, Bradley D; Sohn, Michael D; Long, Thomas; Langstaff, John; Williams, Ronald; Isaacs, Kristin; Meng, Qing Yu; Stallings, Casson; Smith, Luther

    2014-11-01

    A critical aspect of air pollution exposure assessments is estimation of the air exchange rate (AER) for various buildings where people spend their time. The AER, which is the rate of exchange of indoor air with outdoor air, is an important determinant for entry of outdoor air pollutants and for removal of indoor-emitted air pollutants. This paper presents an overview and critical analysis of the scientific literature on empirical and physically based AER models for residential and commercial buildings; the models highlighted here are feasible for exposure assessments as extensive inputs are not required. Models are included for the three types of airflows that can occur across building envelopes: leakage, natural ventilation, and mechanical ventilation. Guidance is provided to select the preferable AER model based on available data, desired temporal resolution, types of airflows, and types of buildings included in the exposure assessment. For exposure assessments with some limited building leakage or AER measurements, strategies are described to reduce AER model uncertainty. This review will facilitate the selection of AER models in support of air pollution exposure assessments. PMID:23715084

  20. Human parainfluenza type 3 virus hemagglutinin-neuraminidase glycoprotein: nucleotide sequence of mRNA and limited amino acid sequence of the purified protein.

    PubMed Central

    Elango, N; Coligan, J E; Jambou, R C; Venkatesan, S

    1986-01-01

    The nucleotide sequence of mRNA for the hemagglutinin-neuraminidase (HN) protein of human parainfluenza type 3 virus obtained from the corresponding cDNA clone had a single long open reading frame encoding a putative protein of 64,254 daltons consisting of 572 amino acids. The deduced protein sequence was confirmed by limited N-terminal amino acid microsequencing of CNBr cleavage fragments of native HN that was purified by immunoprecipitation. The HN protein is moderately hydrophobic and has four potential sites (Asn-X-Ser/Thr) of N-glycosylation in the C-terminal half of the molecule. It is devoid of both the N-terminal signal sequence and the C-terminal membrane anchorage domain characteristic of the hemagglutinin of influenza virus and the fusion (F0) protein of the paramyxoviruses. Instead, it has a single prominent hydrophobic region capable of membrane insertion beginning at 32 residues from the N terminus. This N-terminal membrane insertion is similar to that of influenza virus neuraminidase and the recently reported structures of HN proteins of Sendai virus and simian virus 5. Images PMID:3003381

  1. Activation of Pulmonary Dendritic Cells and Th2-Type Inflammatory Responses on Instillation of Engineered, Environmental Diesel Emission Source or Ambient Air Pollutant Particles in vivo

    PubMed Central

    Bezemer, Gillina F.G.; Bauer, Stephen M.; Oberdörster, Günter; Breysse, Patrick N.; Pieters, Raymond H.H.; Georas, Steve N.; Williams, Marc A.

    2011-01-01

    The biological effects of acute particulate air pollution exposure in host innate immunity remain obscure and have relied largely on in vitro models. We hypothesized that single acute exposure to ambient or engineered particulate matter (PM) in the absence of other secondary stimuli would activate lung dendritic cells (DC) in vivo and provide information on the early immunological events of PM exposure and DC activation in a mouse model naïve to prior PM exposure. Activation of purified lung DC was studied following oropharyngeal instillation of ambient particulate matter (APM). We compared the effects of APM exposure with that of diesel-enriched PM (DEP), carbon black particles (CBP) and silver nanoparticles (AgP). We found that PM species induced variable cellular infiltration in the lungs and only APM exposure induced eosinophilic infiltration. Both APM and DEP activated pulmonary DC and promoted a Th2-type cytokine response from naïve CD4+ T cells ex vivo. Cultures of primary peribronchial lymph node cells from mice exposed to APM and DEP also displayed a Th2-type immune response ex vivo. We conclude that exposure of the lower airway to various PM species induces differential immunological responses and immunomodulation of DC subsets. Environmental APM and DEP activated DC in vivo and provoked a Th2 response ex vivo. By contrast, CBP and AgP induced altered lung tissue barrier integrity but failed to stimulate CD4+ T cells as effectively. Our work suggests that respirable pollutants activate the innate immune response with enhanced DC activation, pulmonary inflammation and Th2-immune responsiveness. PMID:21099199

  2. Air Pollution

    MedlinePlus

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

  3. 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 ...

  4. True-Depth: a new type of true 3D volumetric display system suitable for CAD, medical imaging, and air-traffic control

    NASA Astrophysics Data System (ADS)

    Dolgoff, Eugene

    1998-04-01

    Floating Images, Inc. is developing a new type of volumetric monitor capable of producing a high-density set of points in 3D space. Since the points of light actually exist in space, the resulting image can be viewed with continuous parallax, both vertically and horizontally, with no headache or eyestrain. These 'real' points in space are always viewed with a perfect match between accommodation and convergence. All scanned points appear to the viewer simultaneously, making this display especially suitable for CAD, medical imaging, air-traffic control, and various military applications. This system has the potential to display imagery so accurately that a ruler could be placed within the aerial image to provide precise measurement in any direction. A special virtual imaging arrangement allows the user to superimpose 3D images on a solid object, making the object look transparent. This is particularly useful for minimally invasive surgery in which the internal structure of a patient is visible to a surgeon in 3D. Surgical procedures can be carried out through the smallest possible hole while the surgeon watches the procedure from outside the body as if the patient were transparent. Unlike other attempts to produce volumetric imaging, this system uses no massive rotating screen or any screen at all, eliminating down time due to breakage and possible danger due to potential mechanical failure. Additionally, it is also capable of displaying very large images.

  5. Estimation of lower flammability limits of C-H compounds in air at atmospheric pressure, evaluation of temperature dependence and diluent effect.

    PubMed

    Mendiburu, Andrés Z; de Carvalho, João A; Coronado, Christian R

    2015-03-21

    Estimation of the lower flammability limits of C-H compounds at 25 °C and 1 atm; at moderate temperatures and in presence of diluent was the objective of this study. A set of 120 C-H compounds was divided into a correlation set and a prediction set of 60 compounds each. The absolute average relative error for the total set was 7.89%; for the correlation set, it was 6.09%; and for the prediction set it was 9.68%. However, it was shown that by considering different sources of experimental data the values were reduced to 6.5% for the prediction set and to 6.29% for the total set. The method showed consistency with Le Chatelier's law for binary mixtures of C-H compounds. When tested for a temperature range from 5 °C to 100 °C, the absolute average relative errors were 2.41% for methane; 4.78% for propane; 0.29% for iso-butane and 3.86% for propylene. When nitrogen was added, the absolute average relative errors were 2.48% for methane; 5.13% for propane; 0.11% for iso-butane and 0.15% for propylene. When carbon dioxide was added, the absolute relative errors were 1.80% for methane; 5.38% for propane; 0.86% for iso-butane and 1.06% for propylene. PMID:25528241

  6. A novel target-type low pressure drop bidirectional optoelectronic air flow sensor for infant artificial ventilation: measurement principle and static calibration.

    PubMed

    Saccomandi, Paola; Schena, Emiliano; Silvestri, Sergio

    2011-02-01

    An optoelectronic target-type volumetric air flow-rate transducer for bidirectional measurements is presented. The sensor is composed of a T-shaped target and two nominally identical LED-photodiode couples which are operated in differential mode. The sensitive surfaces of the photodiodes are differentially shadowed by the deflection of the target, which in turn depends on the gas flow-rate. The principle of operation is described in mathematical terms and the design parameters have been optimized in order to obtain the highest sensitivity along with minimal pressure drop and reduced dimensions. The sensor is placed in a 20 mm diameter hose and was tested with air flow-rate in the typical temperature range of mechanical ventilation between 20 and 40 °C. The theoretical model was validated through experiments carried out in the volumetric flow range from -7.0 to +7.0 l min(-1). The nonlinear behavior allows sensitivities equal to 0.6 V l(-1) min for flow rates ranging from -2.0 to +2.0 l min(-1), equal to 2.0 V l(-1) min for flow rates ranging from -3.0 to -2.0 l min(-1) and from +2.0 to +3.0 l min(-1), up to 5.7 V l(-1) min at higher flow rates ranging from -7.0 to -3.0 l min(-1) and from +3.0 to +7.0 l min(-1). The linear range extends from 3.0 to 7.0 l min(-1) with constant sensitivity equal to 5.7 V l(-1) min. The sensor is able to detect a flow-rate equal to 1.0 l min(-1) with a sensitivity of about 400 mV l(-1) min. The differential nature of the output minimizes the influence of the LEDs' power supply variations and allows to obtain a repeatability in the order of 3% of full scale output. The small pressure drop produced by the sensor placed in-line the fluid stream, of about 2.4 Pa at 7 l min(-1), corresponds to a negligible fluid dynamic resistance lower than 0.34 Pa l(-1) min. PMID:21361616

  7. A novel target-type low pressure drop bidirectional optoelectronic air flow sensor for infant artificial ventilation: Measurement principle and static calibration

    NASA Astrophysics Data System (ADS)

    Saccomandi, Paola; Schena, Emiliano; Silvestri, Sergio

    2011-02-01

    An optoelectronic target-type volumetric air flow-rate transducer for bidirectional measurements is presented. The sensor is composed of a T-shaped target and two nominally identical LED-photodiode couples which are operated in differential mode. The sensitive surfaces of the photodiodes are differentially shadowed by the deflection of the target, which in turn depends on the gas flow-rate. The principle of operation is described in mathematical terms and the design parameters have been optimized in order to obtain the highest sensitivity along with minimal pressure drop and reduced dimensions. The sensor is placed in a 20 mm diameter hose and was tested with air flow-rate in the typical temperature range of mechanical ventilation between 20 and 40 °C. The theoretical model was validated through experiments carried out in the volumetric flow range from -7.0 to +7.0 l min-1. The nonlinear behavior allows sensitivities equal to 0.6 V l-1 min for flow rates ranging from -2.0 to +2.0 l min-1, equal to 2.0 V l-1 min for flow rates ranging from -3.0 to -2.0 l min-1 and from +2.0 to +3.0 l min-1, up to 5.7 V l-1 min at higher flow rates ranging from -7.0 to -3.0 l min-1 and from +3.0 to +7.0 l min-1. The linear range extends from 3.0 to 7.0 l min-1 with constant sensitivity equal to 5.7 V l-1 min. The sensor is able to detect a flow-rate equal to 1.0 l min-1 with a sensitivity of about 400 mV l-1 min. The differential nature of the output minimizes the influence of the LEDs' power supply variations and allows to obtain a repeatability in the order of 3% of full scale output. The small pressure drop produced by the sensor placed in-line the fluid stream, of about 2.4 Pa at 7 l min-1, corresponds to a negligible fluid dynamic resistance lower than 0.34 Pa l-1 min.

  8. Quality of life in type 2 diabetes mellitus patients requiring insulin treatment in Buenos Aires, Argentina: a cross-sectional study

    PubMed Central

    Pichon-Riviere, Andres; Irazola, Vilma; Beratarrechea, Andrea; Alcaraz, Andrea; Carrara, Carolina

    2015-01-01

    Background: Decision-makers have begun to recognize Health-Related Quality of Life (HRQoL) as an important and measurable outcome of healthcare interventions; and HRQoL data is increasingly being used by policy-makers to prioritize health resources. Our objective was to measure HRQoL in a group of Type 2 Diabetes Mellitus (T2DM) patients receiving insulin treatment in Buenos Aires, Argentina. Methods: We conducted a cross-sectional study of patients with T2DM over 21 years of age, treated with either Neutral Protamine Hagedorn (NPH) insulin or Insulin Glargine (IG), who had not changed their baseline schedule in the last 6 months. The recruitment was during 2006–7 in nine private diabetes specialists’ offices in Buenos Aires, Argentina. A standardized diabetes-specific HRQoL questionnaire, the Audit of Diabetes Dependent Quality of Life (ADDQoL), was used. Results: A total of 183 patients were included (93 receiving NPH and 90 receiving IG). The mean QoL score was: 0.98 (SD: 0.89) and the diabetes specific QoL was: -1.49 (SD: 0.90). T2DM had a negative impact on HRQoL with a mean Average Weighted Impact (AWI) score on QoL of -1.77 (SD: 1.58). The greatest negative impact was observed for domains: ‘worries about the future’, ‘freedom to eat’, ‘living conditions’, ‘sex life’, and ‘family life’. The mean AWI score was -1.71 (SD: 1.48) in patients treated with IG and -1.85 (SD: 1.68) in patients receiving NPH, this difference was not statistically significant. Conclusion: The ADDQoL questionnaire is a tool that can be used in Argentina to measure the QoL of patients with diabetes when evaluating diabetes care programs. The scores of QoL in our selected population did not differ from those reported in high-income countries. We expect that the results of this study will increase healthcare providers’ awareness of patients’ perceived QoL and help to overcome the barriers that delay insulin treatment; mainly clinical inertia and patient

  9. 14 CFR 298.35 - Limitations on carriage of mail.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Limitations and Conditions on Exemptions and Operations § 298.35 Limitations on carriage of mail. An air taxi operator...

  10. Development of a solar-powered residential air conditioner

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The initial objective of the program was the optimization (in terms of cost and performance) of a Rankine cycle mechanical refrigeration system which utilizes thermal energy from a flat solar collector for air conditioning residential buildings. However, feasibility investigations of the adsorption process revealed that a dessicant-type air conditioner offers many significant advantages. As a result, limited efforts were expended toward the optimization of such a system.

  11. Human Immunodeficiency Virus Type 1 Monoclonal Antibodies Suppress Acute Simian-Human Immunodeficiency Virus Viremia and Limit Seeding of Cell-Associated Viral Reservoirs

    PubMed Central

    Pegu, Amarendra; Wang, Keyun; McGinnis, Kathleen; Nason, Martha; Foulds, Kathryn; Letukas, Valerie; Schmidt, Stephen D.; Chen, Xuejun; Todd, John Paul; Lifson, Jeffrey D.; Rao, Srinivas; Michael, Nelson L.; Robb, Merlin L.; Mascola, John R.; Koup, Richard A.

    2015-01-01

    ABSTRACT Combination antiretroviral therapy (cART) administered shortly after human immunodeficiency virus type 1 (HIV-1) infection can suppress viremia and limit seeding of the viral reservoir, but lifelong treatment is required for the majority of patients. Highly potent broadly neutralizing HIV-1 monoclonal antibodies (MAbs) can reduce plasma viremia when administered during chronic HIV-1 infection, but the therapeutic potential of these antibodies during acute infection is unknown. We tested the ability of HIV-1 envelope glycoprotein-specific broadly neutralizing MAbs to suppress acute simian-human immunodeficiency virus (SHIV) replication in rhesus macaques. Four groups of macaques were infected with SHIV-SF162P3 and received (i) the CD4-binding-site MAb VRC01; (ii) a combination of a more potent clonal relative of VRC01 (VRC07-523) and a V3 glycan-dependent MAb (PGT121); (iii) daily cART, all on day 10, just prior to expected peak plasma viremia; or (iv) no treatment. Daily cART was initiated 11 days after MAb administration and was continued for 13 weeks in all treated animals. Over a period of 11 days after a single administration, MAb treatment significantly reduced peak viremia, accelerated the decay slope, and reduced total viral replication compared to untreated controls. Proviral DNA in lymph node CD4 T cells was also diminished after treatment with the dual MAb. These data demonstrate the virological effect of potent MAbs and support future clinical trials that investigate HIV-1-neutralizing MAbs as adjunctive therapy with cART during acute HIV-1 infection. IMPORTANCE Treatment of chronic HIV-1 infection with potent broadly neutralizing HIV-1 MAbs has been shown to significantly reduce plasma viremia. However, the antiviral effect of MAb treatment during acute HIV-1 infection is unknown. Here, we demonstrate that MAbs targeting the HIV-1 envelope glycoprotein both suppress acute SHIV plasma viremia and limit CD4 T cell-associated viral DNA. These

  12. Complete nucleotide sequence, genome organization, and biological properties of human immunodeficiency virus type 1 in vivo: evidence for limited defectiveness and complementation.

    PubMed Central

    Li, Y; Hui, H; Burgess, C J; Price, R W; Sharp, P M; Hahn, B H; Shaw, G M

    1992-01-01

    Previous studies of the genetic and biologic characteristics of human immunodeficiency virus type 1 (HIV-1) have by necessity used tissue culture-derived virus. We recently reported the molecular cloning of four full-length HIV-1 genomes directly from uncultured human brain tissue (Y. Li, J. C. Kappes, J. A. Conway, R. W. Price, G. M. Shaw, and B. H. Hahn, J. Virol. 65:3973-3985, 1991). In this report, we describe the biologic properties of these four clones and the complete nucleotide sequences and genome organization of two of them. Clones HIV-1YU-2 and HIV-1YU-10 were 9,174 and 9,176 nucleotides in length, differed by 0.26% in nucleotide sequence, and except for a frameshift mutation in the pol gene in HIV-1YU-10, contained open reading frames corresponding to 5'-gag-pol-vif-vpr-tat-rev-vpu-env-nef-3' flanked by long terminal repeats. HIV-1YU-2 was fully replication competent, while HIV-1YU-10 and two other clones, HIV-1YU-21 and HIV-1YU-32, were defective. All three defective clones, however, when transfected into Cos-1 cells in any pairwise combination, yielded virions that were replication competent and transmissible by cell-free passage. The cellular host range of HIV-1YU-2 was strictly limited to primary T lymphocytes and monocyte-macrophages, a property conferred by its external envelope glycoprotein. Phylogenetic analyses of HIV-1YU-2 gene sequences revealed this virus to be a member of the North American/European HIV-1 subgroup, with specific similarity to other monocyte-tropic viruses in its V3 envelope amino acid sequence. These results indicate that HIV-1 infection of brain is characterized by the persistence of mixtures of fully competent, minimally defective, and more substantially altered viral forms and that complementation among them is readily attainable. In addition, the limited degree of genotypic heterogeneity observed among HIV-1YU and other brain-derived viruses and their preferential tropism for monocyte-macrophages suggest that viral

  13. Plasma B-type natriuretic peptide levels are poorly related to the occurrence of ischemia or ventricular arrhythmias during symptom-limited exercise in low-risk patients

    PubMed Central

    Porta, Andreu; Candell-Riera, Jaume; Agulló, Luis; Aguadé-Bruix, Santiago; de León, Gustavo; Figueras, Jaume; Garcia-Dorado, David

    2016-01-01

    Introduction The usefulness of B-type natriuretic peptide (BNP) as a marker of ischemia is controversial. BNP levels have predicted arrhythmias in various settings, but it is unknown whether they are related to exercise-induced ischemic ventricular arrhythmias. Material and methods We analyzed in 63 patients (64 ±14 years, 65% male, 62% with known coronary disease) undergoing exercise stress single-photon emission computed tomography (SPECT) the association between plasma BNP values (before and 15 min after exercise) and the occurrence of ischemia or ventricular arrhythmias during the test. Results Exercise test (8.1 ±2.7 min, 7.4 ±8.1 metabolic equivalents, 82 ±12% of maximal predicted heart rate) induced reversible perfusion defects in 23 (36%) patients. Eight (13%) patients presented significant arrhythmias (≥ 7 ventricular premature complexes/min, couplets, or non-sustained ventricular tachycardia during exercise or in the first minute of recovery). Median baseline BNP levels were 17.5 (12.4–66.4) pg/ml in patients developing scintigraphic ischemia and 45.6 (13.2–107.4) pg/ml in those without ischemia (p = 0.137). The BNP levels increased after exercise (34.4 (15.3–65.4)% increment over baseline, p < 0.001), but the magnitude of this increase was not related to SPECT positivity (35.7 (18.8–65.4)% vs. 27.9 (5.6–64.0)% in patients with and without ischemia, respectively, p = 0.304). No significant association was found between BNP values (at baseline or their change during the test) and ventricular arrhythmias. Conclusions Plasma BNP values – at baseline or after exercise – were not associated with myocardial ischemia or with ventricular arrhythmia during exercise SPECT. These results highlight the limited usefulness of this biomarker to assess acute ischemia. PMID:27186178

  14. The stability and generation pattern of thermally formed isocyanic acid (ICA) in air - potential and limitations of proton transfer reaction-mass spectrometry (PTR-MS) for real-time workroom atmosphere measurements.

    PubMed

    Jankowski, Mikolaj Jan; Olsen, Raymond; Thomassen, Yngvar; Molander, Paal

    2016-07-13

    Isocyanic acid (ICA) in vapour phase has been reported to be of unstable nature, making the occupational hygienic relevance of ICA questionable. The stability of pure ICA in clean air at different humidity conditions was investigated by Fourier transform-infrared spectrometric (FT-IR) measurements. Furthermore, the stability of ICA in a complex atmosphere representative thermal degradation hot-work procedures were examined by performing parallel measurements by proton transfer reaction-mass spectrometric (PTR-MS) instrumentation and off-line denuder air sampling using di-n-butylamine (as a derivatization agent prior to liquid chromatography mass spectrometric (LC-MS) determination). The apparent half-life of ICA in pure ICA atmospheres was 16 to 4 hours at absolute humidity (AH) in the range 4.2 to 14.6 g m(-3), respectively. In a complex atmosphere at an initial AH of 9.6 g m(-3) the apparent half-life of ICA was 8 hours, as measured with the denuder method. Thus, thermally formed ICA is to be considered as a potential occupational hazard with regard to inhalation. The generation pattern of ICA formed during controlled gradient (100-540 °C) thermal decomposition of different polymers in the presence of air was examined by parallel PTR-MS and denuder air sampling. According to measurement by denuder sampling ICA was the dominant aliphatic isocyanate formed during the thermal decomposition of all polymers. The real-time measurements of the decomposed polymers revealed different ICA generation patterns, with initial appearance of thermally released ICA in the temperature range 200-260 °C. The PTR-MS ICA measurements was however affected by mass overlap from other decomposition products at m/z 44, illustrated by a [ICA]Denuder/[ICA]PTR-MS ratio ranging from 0.04 to 0.90. These findings limits the potential use of PTR-MS for real time measurements of thermally released ICA in field, suggesting parallel sampling with short-term sequential off-line methodology. PMID

  15. GIS implementation in air pollution analysis

    SciTech Connect

    Chaaban, F.G.

    1998-07-01

    Air quality modeling and simulation is an indispensable tool used in different environmental studies that attempt to estimate air pollution levels caused by existing or planned combustion processes, to evaluate proposed emission reduction technologies, to select sites for new emission sources, and accordingly to establish emission control strategies in different energy conversion sectors. Modeling techniques, based on established mathematical formulation, are widely used for simulating air pollution caused mainly by the transportation and electric power sectors. Geographic information systems, GIS, link spatial information to alphanumeric information thus developing geographically referenced database. GIS systems have already been incorporated successfully into several fields in the energy sector and are proven to be a very efficient and robust tool for relevant analysis. In the environmental studies, GIS can answer many questions related to air pollution such as pollution sources as well as identification of regions in which the concentration may exceed limits set by local and international standards. The work presented in this paper is aimed at integrating GIS into air pollution analysis. The main objective is to estimate, using advanced graphical illustrations, the concentration levels of different types of air effluents emitted from point, line, or area sources. The integrated package is then used to examine the influence of various mitigation strategies on the air pollutants levels, and hence to evaluate the effectiveness of these strategies. The paper is concluded by case studies from the transportation and power sectors.

  16. Lawsuits in the Air.

    ERIC Educational Resources Information Center

    Hays, Larry

    2000-01-01

    Discusses why indoor air quality problems in schools should be treated, not only as a health problem issue, but as a potential for legal actions. What types of proof are needed to make a legal claim involving indoor air problems are addressed as are the elements which constitute a "sick building." (GR)

  17. THE SPATIAL AND TEMPORAL DISTRIBUTION OF CHLORPYRIFOS IN THE U.S. EPA INDOOR AIR QUALITY (IAQ) TEST HOUSE FOLLOWING CRACK AND CREVICE TYPE APPLICATIONS

    EPA Science Inventory

    Pesticides found in homes may result from indoor applications to control household pests or by translocation from outdoor sources. Pesticides disperse according to their physical properties and other factors such as human activity, air exchange, temperature and humidity. Insect...

  18. THE DISTRIBUTION OF CHLORPYRIFOS FOLLOWING A CRACK AND CREVICE TYPE APPLICAITON IN THE U.S. EPA INDOOR AIR QUALITY (IAQ) TEST HOUSE

    EPA Science Inventory

    Pesticides found in homes may result from indoor applications to control household pests or by translocation from outdoor sources. Pesticides disperse according to their physical properties and other factors such as human activity, residential air exchange, temperature and humi...

  19. 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 ...

  20. Effect of Heat Treatment in Air on Thermoelectric Properties of Polycrystalline Type-I Silicon-Based Clathrate: Ba8Al15Si31

    NASA Astrophysics Data System (ADS)

    Anno, Hiroaki; Shirataki, Ritsuko

    2015-06-01

    The effect of heat treatment in air on the thermoelectric properties was investigated for polycrystalline Ba8Al15Si31, where the Al content is almost at the maximum in the Ba8Al x Si46- x system, to evaluate the thermal stability in air at high temperatures, which is indispensable for practical use in thermoelectric applications. Samples were prepared by combining arc melting and spark plasma sintering techniques. Heat treatments were performed in air at 873 K for 10 days and 20 days. The Seebeck coefficient, electrical conductivity, and thermal conductivity were measured before and after the heat treatments. The microstructure and chemical composition were also analyzed before and after the heat treatments, using scanning electron microscopy with energy-dispersive x-ray spectroscopy. Although an oxidation layer was formed on the surface by the heat treatment in air, the chemical composition of the interior of Ba8Al15Si31 was found to be stable in air at 873 K for 10 days and 20 days. The Seebeck coefficient, the electrical conductivity, and the thermal conductivity were found to be almost unchanged after the heat treatment, indicating that Ba8Al15Si31 clathrate is promising as a thermoelectric material with high thermal stability for use in air at 873 K.