Science.gov

Sample records for recirculating facility built

  1. Recirculating Linear Accelerators for Future Muon Facilities

    SciTech Connect

    S.A. Bogacz, K.B.Beard, R.P. Johnson

    2010-05-01

    Neutrino Factories (NF) and Muon Colliders (MC) require rapid acceleration of short-lived muons to multi-GeV and TeV energies. A Recirculating Linear Accelerator (RLA) that uses superconducting RF structures can provide exceptionally fast and economical acceleration to the extent that the focusing range of the RLA quadrupoles allows each muon to pass several times through each high-gradient cavity. A new concept of rapidly changing the strength of the RLA focusing quadrupoles as the muons gain energy is being developed to increase the number of passes that each muon will make in the RF cavities, leading to greater cost effectiveness.

  2. Performance of the prototype gas recirculation system with built-in RGA for INO RPC system

    NASA Astrophysics Data System (ADS)

    Bhuyan, M.; Datar, V. M.; Joshi, A.; Kalmani, S. D.; Mondal, N. K.; Rahman, M. A.; Satyanarayana, B.; Verma, P.

    2012-01-01

    An open loop gas recovery and recirculation system has been developed for the INO RPC system. The gas mixture coming from RPC exhaust is first desiccated by passing through molecular sieve (3 Å+4 Å). Subsequent scrubbing over basic active alumina removes toxic and acidic contaminants. The Isobutane and Freon are then separated by diffusion and liquefied by fractional condensation by cooling up to -26C. A Residual Gas Analyser (RGA) is being used in the loop to study the performance of the recirculation system. The results of the RGA analysis will be discussed.

  3. Feasibility study for a recirculating linac-based facility for femtosecond dynamics

    SciTech Connect

    Corlett, J.N.; Barry, W.; Barletta, W.A.; Byrd, J.M.; DeSantis, S.; Doolittle, L.; Fawley, W.; Green, M.A.; Hartman, N.; Heimann, P.; Kairan, D.; Kujawski, E.; Li, D.; Lidia, S.; Luft, P.; McClure, R.; Parmigiani, F.; Petroff, Y.; Pirkl, W.; Placidi, M.; Reavill, D.; Reichel, I.; Rimmer, R.A.; Ratti, A.; Robinson, K.E.; Sannibale, F.; Schoenlein, R.; Staples, J.; Tanabe, J.; Truchlikova, D.; Wan, W.; Wang, S.; Wells, R.; Wolski, A.; Zholents, A.

    2002-12-21

    LBNL is pursuing design studies and the scientific program for a facility dedicated to the production of x-ray pulses with ultra-short time duration, for application in dynamical studies of processes in physics, biology, and chemistry. The proposed x-ray facility has the short x-ray pulse length ({approx}60 fs FWHM) necessary to study very fast dynamics, high flux (up to approximately 10E11 photons/sec/0.1 percentBW) to study weakly scattering systems, and tuneability over 1-12 keV photon energy. The hard x-ray photon production section of the machine accommodates seven 2-m long undulators. Design studies for longer wavelength sources, using high-gain harmonic generation, are in progress. The x-ray pulse repetition rate of 10 kHz is matched to studies of dynamical processes (initiated by ultra-short laser pulses) that typically have a long recovery time or are not generally cyclic or reversible and need time to allow relaxation, replacement, or flow of the sample. The technique for producing ultra-short x-ray pulses uses relatively long electron bunches to minimize high-peak-current collective effects, and the ultimate x-ray duration is achieved by a combination of bunch manipulation and optical compression. Synchronization of x-ray pulses to sample excitation signals is expected to be of order 50 - 100 fs. Techniques for making use of the recirculating geometry to provide beam-based signals from early passes through the machine are being studied.

  4. LUX - a recirculating linac-based facility for ultrafast X-ray science

    SciTech Connect

    Corlett, J.N.; Barletta, W.A.; DeSantis, S.; Doolittle, L.; Fawley, W.M.; Heimann, P.; Leone, S.; Lidia, S.; Li, D.; Penn, G.; Ratti, A.; Reinsch, M.; Schoenlein, R.; Staples, J.; Stover, G.; Virostek, S.; Wan, W.; Wells, R.; Wilcox, R.; Wolski, A.; Wurtele, J.; Zholents, A.

    2004-06-29

    We present recent developments in design concepts for LUX - a source of ultra-short synchrotron radiation pulses based on a recirculating superconducting linac. The source produces high-flux x-ray pulses with duration of 100 fs or less at a 10 kHz repetition rate, optimized for the study of ultra-fast dynamics across many fields of science [1]. Cascaded harmonic generation in free-electron lasers (FEL's) produces coherent radiation in the VUV-soft x-ray regime, and a specialized technique is used to compress spontaneous emission for ultra-short-pulse photon production in the 1-10 keV range. High-brightness electron bunches of 2-3 mm-mrad emittance at 1 nC charge in 30 ps duration are produced in an rf photocathode gun and compressed to 3 ps duration following an injector linac, and recirculated three times through a 1 GeV main linac. In each return path, independently tunable harmonic cascades are inserted to produce seeded FEL radiation in selected photon energy ranges from approximately 20 eV with a single stage of harmonic generation, to 1 keV with a four-stage cascade. The lattice is designed to minimize emittance growth from effects such as coherent synchrotron radiation (CSR), and resistive wall wakefields. Timing jitter between pump lasers and x-ray pulses is minimized by use of a stable optical master oscillator, distributing timing signals over actively stabilized fiber-optic, phase-locking all lasers to the master oscillator, and generating all rf signals from the master oscillator. We describe technical developments including techniques for minimizing power dissipation in a high repetition rate rf photocathode gun, beam dynamics in two injector configurations, independently tunable beamlines for VUV and soft x-ray production by cascaded harmonic generation, a fast kicker design, timing systems for providing synchronization between experimental pump lasers and the x-ray pulse, and beamline design for maintaining nm-scale density modulation.

  5. USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES

    SciTech Connect

    Michael N. DiFilippo

    2004-08-01

    The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. Deliverable 2 focuses on transportation--the largest obstacle to produced water reuse in the San Juan Basin (the Basin). Most of the produced water in the Basin is stored in tanks at the well head and must be transported by truck to salt water disposal (SWD) facilities prior to injection. Produced water transportation requirements from the well head to SJGS and the availability of existing infrastructure to transport the water are discussed in this deliverable.

  6. USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES

    SciTech Connect

    Michael N. DiFilippo

    2004-08-01

    The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. Deliverable 1 presents a general assessment of produced water generation in the San Juan Basin in Four Corners Area of New Mexico. Oil and gas production, produced water handling and disposal, and produced water quantities and chemistry are discussed. Legislative efforts to enable the use of this water at SJGS are also described.

  7. USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES

    SciTech Connect

    Kent Zammit; Michael N. DiFilippo

    2005-01-01

    The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. Produced water is generated nationally as a byproduct of oil and gas production. Seven states generate 90 percent of the produced water in the continental US. About 37 percent of the sources documented in the US Geological Survey's (USGS) Produced Waters Database have a TDS of less than 30,000 mg/l. This is significant because produced water treatment for reuse in power plants was found to be very costly above 30,000 mg/l TDS. For the purposes of this report, produced water treatment was assessed using the technologies evaluated for the San Juan Generating Station (SJGS) in Deliverable 3, Treatment and Disposal Analysis. Also, a methodology was developed to readily estimate capital and operating costs for produced water treatment. Two examples are presented to show how the cost estimating methodology can be used to evaluate the cost of treatment of produced water at power plants close to oil and gas production.

  8. Evaluating Alternative Methodologies for Capturing As-Built Building Information Models (BIM) For Existing Facilities

    DTIC Science & Technology

    2010-08-01

    Scale Definitions (NASA TLX 2003). Title Endpoints Descriptions Mental demand Low/High How much mental and perceptual activity was required (e.g...for realistic, scaled models. • Limitations o Full facility model/photos requires scanning each room o COBIE data capturing to be accomplished...Ultra-Mobile PC Panasonic Toughbook U1 Fully Rugged UMPC $2,499 Each X Panasonic U1 (http://catalog2. panas onic.com) Additional

  9. Legionella and risk management in hospitals-A bibliographic research methodology for people responsible for built environment and facility management.

    PubMed

    Leiblein, Thomas W; Tucker, Matthew; Ashall, Mal; Lee, Susanne B; Gollnisch, Carsten; Hofer, Susanne

    2016-11-01

    An ongoing research project investigates the roles and duties of persons responsible for the built environment with respect to risk management of water systems and Legionella prevention from a facility management's perspective. Our literature review provides an approach for selecting and analysing abstracts of initially 177 journal articles, subjected to certain topic-specific inclusion and exclusion criteria. Different decision strategies of either logic 'yes/no', Boolean operators 'OR' or 'AND' and decisions for single counts or cumulative counts of the identified three principal keywords 'Legionella', 'hospital' and 'water', were completed. A final list of ten principal reference articles from 29 journals was compiled. It suggests that the interconnected perspective of water systems, Legionella and hospitals seems to be underrepresented in the field of the built environment and facility management. The term 'stakeholder', which would refer to decision-makers, was not found more than once. Our result is a useful summary of established sources of information on environmental Legionella research. The results can be helpful for those new to the topic.

  10. A Recovery-Oriented Care Approach: Weighing the Pros and Cons of a Newly Built Mental Health Facility.

    PubMed

    Ahern, Catherine Clark; Bieling, Peter; McKinnon, Margaret C; McNeely, Heather E; Langstaff, Karen

    2016-02-01

    The current study adopted a recovery-oriented care approach by emphasizing patients' perspectives and experiences regarding changes to a newly built mental health facility. The inpatient entrance, or "portal," intended to balance the aims of recovery-oriented care with minimizing risk. A mixed-methods study of the portal's pros and cons was conducted, according to four themes: (a) autonomy versus inconvenience; (b) safety and security versus stigma; (c) unit door versus portal operating costs; and (d) privacy versus community integration. Focus groups engaging with patients (N = 39) indicated that the design effectively supported recovery-oriented care. Patients did not find the portal to be stigmatizing or triggering and valued the safety and privacy it created, and visitors also generally had a positive experience. Survey responses (N = 101) from portal users were also positive about the new design. The study findings suggest that the pros outweighed the cons of the new design. [Journal of Psychosocial Nursing and Mental Health Services, 54(2), 39-48.].

  11. Recirculating rotary gas compressor

    DOEpatents

    Weinbrecht, J.F.

    1992-02-25

    A positive displacement, recirculating Roots-type rotary gas compressor is described which operates on the basis of flow work compression. The compressor includes a pair of large diameter recirculation conduits which return compressed discharge gas to the compressor housing, where it is mixed with low pressure inlet gas, thereby minimizing adiabatic heating of the gas. The compressor includes a pair of involutely lobed impellers and an associated port configuration which together result in uninterrupted flow of recirculation gas. The large diameter recirculation conduits equalize gas flow velocities within the compressor and minimize gas flow losses. The compressor is particularly suited to applications requiring sustained operation at higher gas compression ratios than have previously been feasible with rotary pumps, and is particularly applicable to refrigeration or other applications requiring condensation of a vapor. 12 figs.

  12. Recirculating rotary gas compressor

    DOEpatents

    Weinbrecht, John F.

    1992-01-01

    A positive displacement, recirculating Roots-type rotary gas compressor which operates on the basis of flow work compression. The compressor includes a pair of large diameter recirculation conduits (24 and 26) which return compressed discharge gas to the compressor housing (14), where it is mixed with low pressure inlet gas, thereby minimizing adiabatic heating of the gas. The compressor includes a pair of involutely lobed impellers (10 and 12) and an associated port configuration which together result in uninterrupted flow of recirculation gas. The large diameter recirculation conduits equalize gas flow velocities within the compressor and minimize gas flow losses. The compressor is particularly suited to applications requiring sustained operation at higher gas compression ratios than have previously been feasible with rotary pumps, and is particularly applicable to refrigeration or other applications requiring condensation of a vapor.

  13. Preoperational test report, recirculation condenser cooling systems

    SciTech Connect

    Clifton, F.T.

    1997-11-04

    This represents a preoperational test report for Recirculation Condenser Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The four system provide condenser cooling water for vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102. Each system consists of a valved piping loop, a pair of redundant recirculation pumps, a closed-loop evaporative cooling tower, and supporting instrumentation; equipment is located outside the farm on concrete slabs. Piping is routed to the each ventilation condenser inside the farm via below-grade concrete trenches. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  14. High ratio recirculating gas compressor

    DOEpatents

    Weinbrecht, John F.

    1989-01-01

    A high ratio positive displacement recirculating rotary compressor is disclosed. The compressor includes an integral heat exchanger and recirculation conduits for returning cooled, high pressure discharge gas to the compressor housing to reducing heating of the compressor and enable higher pressure ratios to be sustained. The compressor features a recirculation system which results in continuous and uninterrupted flow of recirculation gas to the compressor with no direct leakage to either the discharge port or the intake port of the compressor, resulting in a capability of higher sustained pressure ratios without overheating of the compressor.

  15. High ratio recirculating gas compressor

    DOEpatents

    Weinbrecht, J.F.

    1989-08-22

    A high ratio positive displacement recirculating rotary compressor is disclosed. The compressor includes an integral heat exchanger and recirculation conduits for returning cooled, high pressure discharge gas to the compressor housing to reducing heating of the compressor and enable higher pressure ratios to be sustained. The compressor features a recirculation system which results in continuous and uninterrupted flow of recirculation gas to the compressor with no direct leakage to either the discharge port or the intake port of the compressor, resulting in a capability of higher sustained pressure ratios without overheating of the compressor. 10 figs.

  16. Preoperational test report, recirculation ventilation systems

    SciTech Connect

    Clifton, F.T.

    1997-11-11

    This represents a preoperational test report for Recirculation Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102 and supports the ability to exhaust air from each tank. Each system consists of a valved piping loop, a fan, condenser, and moisture separator; equipment is located inside each respective tank farm in its own hardened building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  17. Nuclear reactors built, being built, or planned 1993

    SciTech Connect

    Not Available

    1993-08-01

    Nuclear Reactors Built, Being Built, or Planned contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1993. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington headquarters and field offices of DOE; from the US Nuclear Regulatory Commission (NRC); from the US reactor manufacturers who are the principal nuclear embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: (1) a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; (2) tables of data for reactors operating, being built, or planned; and (3) tables of data for reactors that have been shut down permanently or dismantled. The reactors are subdivided into the following parts: civilian, production, military, export, and critical assembly.

  18. Steering algorithms for a small recirculating heavy-ion accelerator

    SciTech Connect

    Sharp, W.M.; Grote, D.P.; Hemandez, G.W.

    1997-11-07

    Beam-steering algorithms are proposed for a small recirculating induction accelerator being built at the Lawrence Livermore National Laboratory. The principal problem is that the transverse position and velocity of the beam must be inferred from capacitive position monitors, and this determination is complicated by the limited probe resolution and by the lattice errors within steering modules. The fluid/envelope code CIRCE is used to evaluate these algorithms.

  19. A research facility for habitation questions to be built at the German Aerospace Center in Cologne: future challenges of Space medicine

    PubMed Central

    Koch, B; Gerzer, R

    2008-01-01

    For long term habitation in space and for living on Moon and Mars, many questions still need to be resolved. Such habitation questions include prevention of and rehabilitation from negative effects of weightlessness that are, in many instances, comparable to problems of aging people on Earth as well as of patients during and recovery from long term stays in bed. Therefore the DLR Institute of Aerospace Medicine has designed a concept for a research facility that will make it possible to join space research directly with terrestrial applications. From a strategic point of view, one major emphasis of :envihab is to form a closely interrelated network of scientists and the industry and the public. The project has been in the planning phase for several years. After an international architectural contest, the winning concept was selected in 2007 by a Jury with ESA participation. PMID:19048099

  20. A research facility for habitation questions to be built at the German Aerospace Center in Cologne: future challenges of Space medicine.

    PubMed

    Koch, B; Gerzer, R

    2008-08-01

    For long term habitation in space and for living on Moon and Mars, many questions still need to be resolved. Such habitation questions include prevention of and rehabilitation from negative effects of weightlessness that are, in many instances, comparable to problems of aging people on Earth as well as of patients during and recovery from long term stays in bed. Therefore the DLR Institute of Aerospace Medicine has designed a concept for a research facility that will make it possible to join space research directly with terrestrial applications. From a strategic point of view, one major emphasis of :envihab is to form a closely interrelated network of scientists and the industry and the public. The project has been in the planning phase for several years. After an international architectural contest, the winning concept was selected in 2007 by a Jury with ESA participation.

  1. Nuclear reactors built, being built, or planned, 1991

    SciTech Connect

    Simpson, B.

    1992-07-01

    This document contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1991. The book is divided into three major sections: Section 1 consists of a reactor locator map and reactor tables; Section 2 includes nuclear reactors that are operating, being built, or planned; and Section 3 includes reactors that have been shut down permanently or dismantled. Sections 2 and 3 contain the following classification of reactors: Civilian, Production, Military, Export, and Critical Assembly. Export reactor refers to a reactor for which the principal nuclear contractor is an American company -- working either independently or in cooperation with a foreign company (Part 4, in each section). Critical assembly refers to an assembly of fuel and assembly of fuel and moderator that requires an external source of neutrons to initiate and maintain fission. A critical assembly is used for experimental measurements (Part 5).

  2. Nuclear reactors built, being built, or planned 1996

    SciTech Connect

    1997-08-01

    This publication contains unclassified information about facilities, built, being built, or planned in the United States for domestic use or export as of December 31, 1996. The Office of Scientific and Technical Information, U.S. Department of Energy, gathers this information annually from Washington headquarters, and field offices of DOE; from the U.S. Nuclear Regulatory Commission (NRC); from the U. S. reactor manufacturers who are the principal nuclear contractors for foreign reactor locations; from U.S. and foreign embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: (1) a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; (2) tables of data for reactors operating, being built, or planned; and (3) tables of data for reactors that have been shut down permanently or dismantled.

  3. New design incinerator being built

    SciTech Connect

    Not Available

    1980-09-01

    A $14 million garbage-burning facility is being built by Reedy Creek Utilities Co. in cooperation with DOE at Lake Buena Vista, Fla., on the edge of Walt Disney World. The nation's first large-volume slagging pyrolysis incinerator will burn municipal waste in a more beneficial way and supply 15% of the amusement park's energy demands. By studying the new incinerators slag-producing capabilities, engineers hope to design similar facilities for isolating low-level nuclear wastes in inert, rocklike slag.

  4. Introduction of electrodehydrators with built-in jet mixers

    SciTech Connect

    Gershuni, S.S.; Baimbetov, A.M.; Idrisova, T.S.; Makhov, A.F.

    1985-09-01

    This paper describes an effective technique of crude oil desalting which is recirculation of water within the electrodehydrator by means of built-in jet mixers. Vertical electrodehydrators with built-in jet mixers have been tested and approved at the Novo-Ufa refinery. Design and operation of the vessel is described. Results from analyses of the oil during the test period are summarized. Retrofitting of electrodehydrators with built-in jet mixers proved increased capacity and the consumption of water and electric power in desalting was cut in half while oil loss in the electric desalting units was reduced substantially.

  5. Na+ recirculation and isosmotic transport.

    PubMed

    Larsen, E H; Møbjerg, N

    2006-01-01

    The Na(+) recirculation theory for solute-coupled fluid absorption is an expansion of the local osmosis concept introduced by Curran and analyzed by Diamond & Bossert. Based on studies on small intestine the theory assumes that the observed recirculation of Na(+) serves regulation of the osmolarity of the absorbate. Mathematical modeling reproducing bioelectric and hydrosmotic properties of small intestine and proximal tubule, respectively, predicts a significant range of observations such as isosmotic transport, hyposmotic transport, solvent drag, anomalous solvent drag, the residual hydraulic permeability in proximal tubule of AQP1 (-/-) mice, and the inverse relationship between hydraulic permeability and the concentration difference needed to reverse transepithelial water flow. The model reproduces the volume responses of cells and lateral intercellular space (lis) following replacement of luminal NaCl by sucrose as well as the linear dependence of volume absorption on luminal NaCl concentration. Analysis of solvent drag on Na(+) in tight junctions provides explanation for the surprisingly high metabolic efficiency of Na(+) reabsorption. The model predicts and explains low metabolic efficiency in diluted external baths. Hyperosmolarity of lis is governed by the hydraulic permeability of the apical plasma membrane and tight junction with 6-7 mOsm in small intestine and < or = 1 mOsm in proximal tubule. Truly isosmotic transport demands a Na(+) recirculation of 50-70% in small intestine but might be barely measurable in proximal tubule. The model fails to reproduce a certain type of observations: The reduced volume absorption at transepithelial osmotic equilibrium in AQP1 knockout mice, and the stimulated water absorption by gallbladder in diluted external solutions. Thus, it indicates cellular regulation of apical Na(+) uptake, which is not included in the mathematical treatment.

  6. Recirculation in multiple wave conversions

    SciTech Connect

    Kaufman, A. N.; Brizard, A.J.; Kaufman, A.N.; Tracy, E.R.

    2008-07-30

    A one-dimensional multiple wave-conversion model is constructed that allows energy recirculation in ray phase space. Using a modular eikonal approach, the connection coefficients for this model are calculated by ray phase-space methods. Analytical results (confirmed numerically) show that all connection coefficients exhibit interference effects that depend on an interference phase, calculated from the coupling constants and the area enclosed by the intersecting rays. This conceptual model, which focuses on the topology of intersecting rays in phase space, is used to investigate how mode conversion between primary and secondary waves is modified by the presence of a tertiary wave.

  7. Gas recirculator for acyclic machines

    NASA Astrophysics Data System (ADS)

    Balsa, T. F.

    1985-05-01

    The present invention relates to acyclic machines of the type using liquid metal collectors, and more particularly to an improvement for retaining the liquid metal in such machines. Radial type acyclic motors and generators generally include a metallic disk rotor rotating on a shaft between electromagnetic stator poles excited by field coils wound concentric with the shaft. Instead of solid brush, current collectors at the rotor periphery, liquid metal collectors are sometimes used to close the electrical current loop between the shaft and the rotor, and an inert pressurized cover gas fills the gaps between the rotating components and the stationary housing. A cover has recirculator in an acyclic generator having liquid metal collectors for reducing entrainment of the liquid metal in the gas. Radial passages in the stator housing provide natural recirculating paths for the cover gas to flow radially outward along the sides of the rotor and return inwardly through the passages. Scoops or lips located inward of the liquid metal collector divert the outward gas flow into the passages to minimize contact of the gas with the liquid metal.

  8. Space hands-on universe telescope and orbiting wide-angle light-collector telescope to be built on the Japanese experiment module exposure facility of the international space station

    NASA Astrophysics Data System (ADS)

    Takahashi, Yoshiyuki; Ebisuzaki, Toshikazu; Pennypacker, Carlton

    1999-01-01

    A concept study to build great observatories on, and deploy from, the ISS is presented. Use of the ISS infra-structure including robotic arms and astronauts' EVA would permit a construction of very large optical telescopes. We envisage that the second phase of the ISS after its initial construction can landmark a new era for both ISS and Space Sciences. Ultimately, this study would plan a 10-or 20-meter class space telescope. For its first step, we envisioned an immediate extension of the Exposed Facility of ISS for building a ``Work-bench'' for this purpose. Initial activities can begin with two modest-sized telescopes soon after the ISS construction. These early missions being studied are space Hands-On Universe Telescope (SHOUT) and Orbiting Wide-angle Light-collector (OWL). SHOUT is a 1-m telescope for science education. It will be built and adjusted on the exposure module of the Japanese Experiment Module (JEM) of the International Space Station by using a robotic arm and the EVA of astronauts. We also seek the possibility to release it from ISS after its perfection on orbit, so that it is free from the vibrations and gas contaminations on and around the ISS. SHOUT is an engineering prototype of 10-m Space Telescope (Space SUBARU Telescope). It would be scaled from the Space-SUBARU telescope so that the testing with the SHOUT would warrant the required specifications for the 10-meter Space-SUBARU construction on the ISS. The goal of the test with the SHOUT is to warrant a spatial resolution of 0.01 arc-seconds using the active/adaptive optics. It will test the following three major engineering challenges: (1) active/adaptive optics in space; (2) building of large structures by astronauts; and (3) release of a spacecraft from ISS to a free-flying orbit. The present feasibility study for the next generation great observatories that are to be built on the JEM Exposure Facility (EF) has been already funded by the Japan Space Forum, under the auspices of the

  9. Space hands-on universe telescope and orbiting wide-angle light-collector telescope to be built on the Japanese experiment module exposure facility of the international space station

    SciTech Connect

    Takahashi, Y.; Ebisuzaki, T.; Pennypacker, C.

    1999-01-01

    A concept study to build great observatories on, and deploy from, the ISS is presented. Use of the ISS infra-structure including robotic arms and astronauts{close_quote} EVA would permit a construction of very large optical telescopes. We envisage that the second phase of the ISS after its initial construction can landmark a new era for both ISS and Space Sciences. Ultimately, this study would plan a 10-or 20-meter class space telescope. For its first step, we envisioned an immediate extension of the Exposed Facility of ISS for building a {open_quotes}Work-bench{close_quotes} for this purpose. Initial activities can begin with two modest-sized telescopes soon after the ISS construction. These early missions being studied are space Hands-On Universe Telescope (SHOUT) and Orbiting Wide-angle Light-collector (OWL). SHOUT is a 1-m telescope for science education. It will be built and adjusted on the exposure module of the Japanese Experiment Module (JEM) of the International Space Station by using a robotic arm and the EVA of astronauts. We also seek the possibility to release it from ISS after its perfection on orbit, so that it is free from the vibrations and gas contaminations on and around the ISS. SHOUT is an engineering prototype of 10-m Space Telescope (Space SUBARU Telescope). It would be scaled from the Space-SUBARU telescope so that the testing with the SHOUT would warrant the required specifications for the 10-meter Space-SUBARU construction on the ISS. The goal of the test with the SHOUT is to warrant a spatial resolution of 0.01 arc-seconds using the active/adaptive optics. It will test the following three major engineering challenges: (1) active/adaptive optics in space; (2) building of large structures by astronauts; and (3) release of a spacecraft from ISS to a free-flying orbit. The present feasibility study for the next generation great observatories that are to be built on the JEM Exposure Facility (EF) has been already funded by the Japan Space

  10. Recirculation in venovenous extracorporeal membrane oxygenation.

    PubMed

    Xie, Ashleigh; Yan, Tristan D; Forrest, Paul

    2016-12-01

    Despite the increasing use of venovenous extracorporeal membrane oxygenation (ECMO) to treat severe respiratory failure, recirculation remains a common complication that may result in severe hypoxemia and end-organ damage. The present review, therefore, examines updated evidence for the causes, measurement, and management of recirculation. Six electronic databases were searched from their dates of inception to January 2016, and 38 relevant studies were selected for analysis. This review revealed that, currently, recirculation is typically calculated from measurement of blood oxygen saturations, although limited evidence suggests that oxygen content may provide a more accurate measure. Dilutional ultrasound may play an additional role in dynamic quantitative monitoring of recirculation, but further human studies are required to validate its clinical use. Although cannula configuration appears to be a key contributor to recirculation in addition to factors such as ECMO flow rate, there are insufficient comparative clinical studies to recommend an optimal cannulation technique for minimizing recirculation. Existing evidence suggests that the dual-lumen cannula may have a low recirculation fraction, but only if correctly positioned. This review underscores the need for more robust clinical and laboratory studies to effectively evaluate and address the persistent problem of recirculation.

  11. Nuclear reactors built, being built, or planned, 1994

    SciTech Connect

    1995-07-01

    This document contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1994. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington headquarters and field offices of DOE; from the US Nuclear Regulatory Commission (NRC); from the US reactor manufacturers who are the principal nuclear contractors for foreign reactor locations; from US and foreign embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; tables of data for reactors operating, being built, or planned; and tables of data for reactors that have been shut down permanently or dismantled. The reactors are subdivided into the following parts: Civilian, Production, Military, Export, and Critical Assembly. Export reactor refers to a reactor for which the principal nuclear contractor is a US company -- working either independently or in cooperation with a foreign company (Part 4). Critical assembly refers to an assembly of fuel and moderator that requires an external source of neutrons to initiate and maintain fission. A critical assembly is used for experimental measurements (Part 5).

  12. Nuclear reactors built, being built, or planned: 1995

    SciTech Connect

    1996-08-01

    This report contains unclassified information about facilities built, being built, or planned in the US for domestic use or export as of December 31, 1995. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington headquarters and field offices of DOE; from the US Nuclear Regulatory Commission (NRC); from the US reactor manufacturers who are the principal nuclear contractors for foreign reactor locations; from US and foreign embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: (1) a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; (2) tables of data for reactors operating, being built, or planned; and (3) tables of data for reactors that have been shut down permanently or dismantled. The reactors are subdivided into the following parts: Civilian, Production, Military, Export, and Critical Assembly. Export reactor refers to a reactor for which the principal nuclear contractor is a US company--working either independently or in cooperation with a foreign company (Part 4). Critical assembly refers to an assembly of fuel and moderator that requires an external source of neutrons to initiate and maintain fission. A critical assembly is used for experimental measurements (Part 5).

  13. Facilities

    NASA Technical Reports Server (NTRS)

    1999-01-01

    An expansion of medical data collection facilities was necessary to implement the Extended Duration Orbiter Medical Project (EDOMP). The primary objective of the EDOMP was to ensure the capability of crew members to reenter the Earth's atmosphere, land, and egress safely following a 16-day flight. Therefore, access to crew members as soon as possible after landing was crucial for most data collection activities. Also, with the advent of EDOMP, the quantity of investigations increased such that the landing day maximum data collection time increased accordingly from two hours to four hours. The preflight and postflight testing facilities at the Johnson Space Center (JSC) required only some additional testing equipment and minor modifications to the existing laboratories in order to fulfill EDOMP requirements. Necessary modifications at the landing sites were much more extensive.

  14. Lattice Design for the LHEC Recirculating Linac

    SciTech Connect

    Sun, Yipeng; Eide, Anders; Zimmermann, Frank; Adolphsen, Chris; /SLAC

    2011-05-20

    In this paper, we present a lattice design for the Large Hadron Electron Collider (LHeC) recirculating linac. The recirculating linac consists of one roughly 3-km long linac hosting superconducting RF (SRF) accelerating cavities, two arcs and one transfer line for the recirculation. In two passes through a pulsed SRF linac the electron beam can get a maximum energy of 140 GeV. Alternatively, in the Energy Recovery Linac (ERL) option the beam passes through a CW linac four times (two passes for acceleration and two for deceleration) for a maximum energy of 60 GeV.

  15. TANK MIXING STUDY WITH FLOW RECIRCULATION

    SciTech Connect

    Lee, S.

    2014-06-25

    The primary objective of this work is to quantify the mixing time when two miscible fluids are mixed by one recirculation pump and to evaluate adequacy of 2.5 hours of pump recirculation to be considered well mixed in SRS tanks, JT-71/72. The work scope described here consists of two modeling analyses. They are the steady state flow pattern analysis during pump recirculation operation of the tank liquid and transient species transport calculations based on the initial steady state flow patterns. The modeling calculations for the mixing time are performed by using the 99% homogeneity criterion for the entire domain of the tank contents.

  16. Recirculating cross-correlation detector

    DOEpatents

    Andrews, W.H. Jr.; Roberts, M.J.

    1985-01-18

    A digital cross-correlation detector is provided in which two time-varying signals are correlated by repetitively comparing data samples stored in digital form to detect correlation between the two signals. The signals are sampled at a selected rate converted to digital form, and stored in separate locations in separate memories. When the memories are filled, the data samples from each memory are first fed word-by-word through a multiplier and summing circuit and each result is compared to the last in a peak memory circuit and if larger than the last is retained in the peak memory. Then the address line to leading signal memory is offset by one byte to affect one sample period delay of a known amount in that memory and the data in the two memories are then multiplied word-by-word once again and summed. If a new result is larger than a former sum, it is saved in the peak memory together with the time delay. The recirculating process continues with the address of the one memory being offset one additional byte each cycle until the address is shifted through the length of the memory. The correlation between the two signals is indicated by the peak signal stored in the peak memory together with the delay time at which the peak occurred. The circuit is faster and considerably less expensive than comparable accuracy correlation detectors.

  17. Assessing peracetic acid as a means to control post-vaccination Saprolegniasis in Atlantic salmon Salmo salar parr in recirculation aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land-based closed containment facilities, utilizing recirculation aquaculture system (RAS) technologies, can reduce or eliminate the introduction of obligate fish pathogens. Regardless, the presence of opportunistic pathogens must be assumed, and these agents can cause disease during unfavorable con...

  18. Flume simulation of sedimentation in recirculating flow

    SciTech Connect

    Schmidt, J.C. ); Rubin, D.M. ); Ikeda, H. )

    1990-05-01

    A 4-m-wide flume at the University of Tsukuba Environmental Research Center was used to simulate flow conditions near debris fans in bedrock gorges. Flow was constricted to 2 m by a semicircular obstruction. During the authors experiments (discharge = 600 L/sec; Froude number of constricted flow = 1) a zone of recirculating current extended 25-30 m downstream from the separation point at the constriction. The pattern and velocity of surface flow was determined using time-lapse photography; subsurface velocity was measured with a two-dimensional electromagnetic current meter. During 32-hr of run time, a fine, very coarse sand mixture was fed into the flow at a rate between 0.5-1 kg/sec. Oscillation ripples developed beneath the separation surface that bounds the recirculation zone, and upstream-migrating dunes and ripples developed within the recirculation zone upstream from the reattachment point. A mid-channel expansion bar was deposited downstream from the reattachment point. Sedimentation within the recirculation zone continued by vertical aggradation and by upstream migration of dunes and ripples. Sediments within the recirculation zone were areally sorted with the finest sediment deposited near the separation point. These patterns are consistent with field observations of bars along the Colorado River in the Grand Canyon.

  19. Built to disappear.

    PubMed

    Bauer, Siegfried; Kaltenbrunner, Martin

    2014-06-24

    Microelectronics dominates the technological and commercial landscape of today's electronics industry; ultrahigh density integrated circuits on rigid silicon provide the computing power for smart appliances that help us organize our daily lives. Integrated circuits function flawlessly for decades, yet we like to replace smart phones and tablet computers every year. Disposable electronics, built to disappear in a controlled fashion after the intended lifespan, may be one of the potential applications of transient single-crystalline silicon nanomembranes, reported by Hwang et al. in this issue of ACS Nano. We briefly outline the development of this latest branch of electronics research, and we present some prospects for future developments. Electronics is steadily evolving, and 20 years from now we may find it perfectly normal for smart appliances to be embedded everywhere, on textiles, on our skin, and even in our body.

  20. Peach bottom recirculation piping replacement ALARA program

    SciTech Connect

    Englesson, G.A.; Hilsmeier, A.E.; Mann, B.J.

    1986-01-01

    In late 1983, Philadelphia Electric Company (PECo) began detailed planning to replace the recirculation, residual heat removal, and part of the reactor water cleanup piping of the Peach Bottom Unit 2 reactor. Included in this work was an estimate of the collective exposure expected during piping replacement. That initial estimate, 1945 man-rem, is compared with the actual collective dose incurred during the piping replacement program. Also included are the exposures incurred during two additional tasks (safe end replacement and recirculation pump disassembly and decontamination) not considered in the initial estimate.

  1. Network Interdependency Modeling for Risk Assessment on Built Infrastructure Systems

    DTIC Science & Technology

    2013-10-01

    inoperability model (IIM) in the analysis of built infrastructure systems . Previous applications of the IIM characterized infrastructure at the national...infrastructure systems and facilities. .............. 86 Figure 15. Analysis results using a common centrality measure. .................................... 90

  2. Production of cobia in recirculating systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Only limited information exists with respect to rearing juvenile cobia Rachycentron canadum to stocker and marketable sizes using recirculating aquaculture systems (RAS). To investigate this topic, two rearing trials were conducted using commercial scale RAS. In Trial 1, juvenile cobia (29 g) we...

  3. Recirculating sprayer for fiber-filled paints

    NASA Technical Reports Server (NTRS)

    Major, R. K.

    1980-01-01

    Recirculating paint sprayer applies spray of coarse filler in highly volatile solvent. Sprayer was developed for applying insulation material containing epxoy resin, glass fibers, and inert fillers suspended in chlorinated solvents. Sprayer resists abrasive action of fiberglass filler and chemical activity of solvent. Pump and position ensure more uniform pressure at spray gun without backpressure regulator, which tended to clog in old sprayer.

  4. Nitrogen removal in recirculated duckweed ponds system.

    PubMed

    Benjawan, L; Koottatep, T

    2007-01-01

    Duckweed-based ponds (DWBPs) have the potential for nitrogen (N) removal from wastewater; however, operational problems such as duckweed die-off regularly occur. In this study, effluent recirculation was applied to the DWBPs to solve the above problem as well as to investigate N removal mechanisms. Two pilot scale recirculated DWBPs were employed to treat municipal wastewater. The average removal efficiencies for TN, TKN and NH4-N were 75%, 89% and 92%, respectively at TN loading of 1.3 g/m2.d and were 73%, 74% and 76%, respectively at TN loading of 3.3 g/m2.d. The effluent of the system under both operational conditions had stable quality and met the effluent standard. Duckweed die-off was not observed during the study, which proves the system stability and effluent recirculation which is thought to be a reason. N-mass balance revealed that nitrification-denitrification and duckweed uptake play major roles in these recirculated DWBPs. The rates of nitrification-denitrification were increased as TN loading was higher, which might be an influence from an abundance of N and a suitable condition. The rates of N uptake by duckweed were found similar and did not depend on the higher TN loading applied, as the duckweed has limited capacity to assimilate it.

  5. A Sketch of the Taiwan Zebrafish Core Facility.

    PubMed

    You, May-Su; Jiang, Yun-Jin; Yuh, Chiou-Hwa; Wang, Chien-Ming; Tang, Chih-Hao; Chuang, Yung-Jen; Lin, Bo-Hung; Wu, Jen-Leih; Hwang, Sheng-Ping L

    2016-07-01

    In the past three decades, the number of zebrafish laboratories has significantly increased in Taiwan. The Taiwan Zebrafish Core Facility (TZCF), a government-funded core facility, was launched to serve this growing community. The Core Facility was built on two sites, one located at the National Health Research Institutes (NHRI, called Taiwan Zebrafish Core Facility at NHRI or TZeNH) and the other is located at the Academia Sinica (Taiwan Zebrafish Core Facility at AS a.k.a. TZCAS). The total surface area of the TZCF is about 180 m(2) encompassing 2880 fish tanks. Each site has a separate quarantine room and centralized water recirculating systems, monitoring key water parameters. To prevent diseases, three main strategies have been implemented: (1) imported fish must be quarantined; (2) only bleached embryos are introduced into the main facilities; and (3) working practices were implemented to minimize pathogen transfer between stocks and facilities. Currently, there is no health program in place; however, a fourth measure for the health program, specific regular pathogen tests, is being planned. In March 2015, the TZCF at NHRI has been AAALAC accredited. It is our goal to ensure that we provide "disease-free" fish and embryos to the Taiwanese research community.

  6. 21 CFR 880.5045 - Medical recirculating air cleaner.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical recirculating air cleaner. 880.5045... Therapeutic Devices § 880.5045 Medical recirculating air cleaner. (a) Identification. A medical recirculating air cleaner is a device used to remove particles from the air for medical purposes. The device...

  7. Pulsed-focusing recirculating linacs for muon acceleration

    SciTech Connect

    Johnson, Rolland

    2014-12-31

    Since the muon has a short lifetime, fast acceleration is essential for high-energy applications such as muon colliders, Higgs factories, or neutrino factories. The best one can do is to make a linear accelerator with the highest possible accelerating gradient to make the accelerating time as short as possible. However, the cost of such a single linear accelerator is prohibitively large due to expensive power sources, cavities, tunnels, and related infrastructure. As was demonstrated in the Thomas Jefferson Accelerator Facility (Jefferson Lab) Continuous Electron Beam Accelerator Facility (CEBAF), an elegant solution to reduce cost is to use magnetic return arcs to recirculate the beam through the accelerating RF cavities many times, where they gain energy on each pass. In such a Recirculating Linear Accelerator (RLA), the magnetic focusing strength diminishes as the beam energy increases in a conventional linac that has constant strength quadrupoles. After some number of passes the focusing strength is insufficient to keep the beam from going unstable and being lost. In this project, the use of fast pulsed quadrupoles in the linac sections was considered for stronger focusing as a function of time to allow more successive passes of a muon beam in a recirculating linear accelerator. In one simulation, it was shown that the number of passes could be increased from 8 to 12 using pulsed magnet designs that have been developed and tested. This could reduce the cost of linac sections of a muon RLA by 8/12, where more improvement is still possible. The expense of a greater number of passes and corresponding number of return arcs was also addressed in this project by exploring the use of ramped or FFAG-style magnets in the return arcs. A better solution, invented in this project, is to use combined-function dipole-quadrupole magnets to simultaneously transport two beams of different energies through one magnet string to reduce costs of return arcs by almost a factor of

  8. Numerical computations of swirling recirculating flow

    NASA Technical Reports Server (NTRS)

    Srinivasan, R.; Mongia, H. C.

    1980-01-01

    Swirling, recirculating, nonreacting flows were computed using a 2D elliptic program consisting of three tasks. The computations in Task 1 and 2 were made using an independent analysis for the two coaxial swirling flows. The Task 2 computations were made using the measured profiles of the mixing region. In Task 3, a modified 2D elliptic program was employed to include the effects of interaction between the inner and outer streams.

  9. [Resistance analyses for recirculated membrane bioreactor].

    PubMed

    Yang, Qi; Huang, Xia; Shang, Hai-Tao; Wen, Xiang-Hua; Qian, Yi

    2006-11-01

    The resistance analyses for recirculated membrane bioreactor by the resistance-in-series model and the modified gel-polarization model respectively were extended to the turbulent ultrafiltration system. The experiments are carried out by dye wastewater in a tubular membrane module, it is found that the permeate fluxes are predicted very well by these models for turbinate systems. And the resistance caused by the concentration polarization is studied; the gel layer resistance is the most important of all the resistances.

  10. High-power picosecond laser pulse recirculation.

    PubMed

    Shverdin, M Y; Jovanovic, I; Semenov, V A; Betts, S M; Brown, C; Gibson, D J; Shuttlesworth, R M; Hartemann, F V; Siders, C W; Barty, C P J

    2010-07-01

    We demonstrate a nonlinear crystal-based short pulse recirculation cavity for trapping the second harmonic of an incident high-power laser pulse. This scheme aims to increase the efficiency and flux of Compton-scattering-based light sources. We demonstrate up to 40x average power enhancement of frequency-doubled submillijoule picosecond pulses, and 17x average power enhancement of 177 mJ, 10 ps, 10 Hz pulses.

  11. High Power Picosecond Laser Pulse Recirculation

    SciTech Connect

    Shverdin, M Y; Jovanovic, I; Semenov, V A; Betts, S M; Brown, C; Gibson, D J; Shuttlesworth, R M; Hartemann, F V; Siders, C W; Barty, C P

    2010-04-12

    We demonstrate a nonlinear crystal-based short pulse recirculation cavity for trapping the second harmonic of an incident high power laser pulse. This scheme aims to increase the efficiency and flux of Compton-scattering based light sources. We demonstrate up to 36x average power enhancement of frequency doubled sub-millijoule picosecond pulses, and 17x average power enhancement of 177 mJ, 10 ps, 10 Hz pulses.

  12. Recirculating gas separator for electric submersible

    SciTech Connect

    Powers, M.L.

    1991-01-01

    This patent describes a gas separator apparatus for a submersible well pump. It comprises: a rotary gas separator means; and recirculating means for recirculating a portion of the liquid discharged from the discharge outlet back to the separating chamber so that a gas-to-liquid ratio in the separator means is substantially lower than a gas-to-liquid ratio of well fluid entering the well fluid inlet wherein the recirculating means. This patent also describes a method of pumping liquid from a well producing well fluids having a relatively high gas-to-liquid ratio. It comprises: centrifugally separating the well fluid into a liquid and a gas with a separator located downhole in the well; directing the separated liquid toward an inlet of a submersible well pump; recycling a portion of the separated liquid to the separator; and providing an effective gas-to-liquid ratio in the separator substantially lower than a gas-to-liquid ratio of the well fluid prior to separation.

  13. Linear microbunching analysis for recirculation machines

    NASA Astrophysics Data System (ADS)

    Tsai, C.-Y.; Douglas, D.; Li, R.; Tennant, C.

    2016-11-01

    Microbunching instability (MBI) has been one of the most challenging issues in designs of magnetic chicanes for short-wavelength free-electron lasers or linear colliders, as well as those of transport lines for recirculating or energy-recovery-linac machines. To quantify MBI for a recirculating machine and for more systematic analyses, we have recently developed a linear Vlasov solver and incorporated relevant collective effects into the code, including the longitudinal space charge, coherent synchrotron radiation, and linac geometric impedances, with extension of the existing formulation to include beam acceleration. In our code, we semianalytically solve the linearized Vlasov equation for microbunching amplification factor for an arbitrary linear lattice. In this study we apply our code to beam line lattices of two comparative isochronous recirculation arcs and one arc lattice preceded by a linac section. The resultant microbunching gain functions and spectral responses are presented, with some results compared to particle tracking simulation by elegant (M. Borland, APS Light Source Note No. LS-287, 2002). These results demonstrate clearly the impact of arc lattice design on the microbunching development. The underlying physics with inclusion of those collective effects is elucidated and the limitation of the existing formulation is also discussed.

  14. Exhaust gas recirculation system for an internal combustion engine

    SciTech Connect

    Wu, Ko-Jen

    2013-05-21

    An exhaust gas recirculation system for an internal combustion engine comprises an exhaust driven turbocharger having a low pressure turbine outlet in fluid communication with an exhaust gas conduit. The turbocharger also includes a low pressure compressor intake and a high pressure compressor outlet in communication with an intake air conduit. An exhaust gas recirculation conduit fluidly communicates with the exhaust gas conduit to divert a portion of exhaust gas to a low pressure exhaust gas recirculation branch extending between the exhaust gas recirculation conduit and an engine intake system for delivery of exhaust gas thereto. A high pressure exhaust gas recirculation branch extends between the exhaust gas recirculation conduit and the compressor intake and delivers exhaust gas to the compressor for mixing with a compressed intake charge for delivery to the intake system.

  15. Passive recirculation in the National Launch System's fuel feedlines

    NASA Technical Reports Server (NTRS)

    Wilson, W. R.; Holt, K. A.

    1993-01-01

    This report contains the passive recirculation tests on the fuel feedline of the National Launch System (NLS). The majority of testing was performed in February 1992, at the National Institute of Standards and Technology in Boulder, CO. The primary objective was to characterize passive recirculation in the NLS fuel feedline. The objective was met by observing the passive recirculation in a one-fifth scale model of the feedline with clear glass sections. The testing was recorded on video tape and with photographs. A description of the testing apparatus and support equipment is included. The experiment indicates that passive recirculation was occurring; higher angles from the horizontal transfer more heat.

  16. Exhaust gas recirculation in a homogeneous charge compression ignition engine

    DOEpatents

    Duffy, Kevin P.; Kieser, Andrew J.; Rodman, Anthony; Liechty, Michael P.; Hergart, Carl-Anders; Hardy, William L.

    2008-05-27

    A homogeneous charge compression ignition engine operates by injecting liquid fuel directly in a combustion chamber, and mixing the fuel with recirculated exhaust and fresh air through an auto ignition condition of the fuel. The engine includes at least one turbocharger for extracting energy from the engine exhaust and using that energy to boost intake pressure of recirculated exhaust gas and fresh air. Elevated proportions of exhaust gas recirculated to the engine are attained by throttling the fresh air inlet supply. These elevated exhaust gas recirculation rates allow the HCCI engine to be operated at higher speeds and loads rendering the HCCI engine a more viable alternative to a conventional diesel engine.

  17. Design of a computerized, temperature-controlled, recirculating aquaria system

    USGS Publications Warehouse

    Widmer, A.M.; Carveth, C.J.; Keffler, J.W.; Bonar, Scott A.

    2006-01-01

    We built a recirculating aquaria system with computerized temperature control to maintain static temperatures, increase temperatures 1 ??C/day, and maintain diel temperature fluctuations up to 10 ??C. A LabVIEW program compared the temperature recorded by thermocouples in fish tanks to a desired set temperature and then calculated the amount of hot or cold water to add to tanks to reach or maintain the desired temperature. Intellifaucet?? three-way mixing valves controlled temperature of the input water and ensured that all fish tanks had the same turnover rate. The system was analyzed over a period of 50 days and was fully functional for 96% of that time. Six different temperature treatments were run simultaneously in 18, 72 L fish tanks and temperatures stayed within 0.5 ??C of set temperature. We used the system to determine the upper temperature tolerance of fishes, but it could be used in aquaculture, ecological studies, or other aquatic work where temperature control is required. ?? 2005 Elsevier B.V. All rights reserved.

  18. Recirculating 1-K-Pot for Pulse-Tube Cryostats

    NASA Technical Reports Server (NTRS)

    Paine, Christopher T.; Naylor, Bret J.; Prouve, Thomas

    2013-01-01

    A paper describes a 1-K-pot that works with a commercial pulse tube cooler for astrophysics instrumentation testbeds that require temperatures <1.7 K. Pumped liquid helium-4 cryostats were commonly used to achieve this temperature. However, liquid helium-4 cryostats are being replaced with cryostats using pulse tube coolers. The closed-cycle 1K-pot system for the pulse tube cooler requires a heat exchanger on the pulse tube, a flow restriction, pump-out line, and pump system that recirculates helium-4. The heat exchanger precools and liquefies helium- 4 gas at the 2.5 to 3.5 K pulse tube cold head. This closed-cycle 1-K-pot system was designed to work with commercially available laboratory pulse tube coolers. It was built using common laboratory equipment such as stainless steel tubing and a mechanical pump. The system is self-contained and requires only common wall power to operate. The lift of 15 mW at 1.1 K and base temperature of 0.97 K are provided continuously. The system can be scaled to higher heat lifts of .30 to 50 mW if desired. Ground-based telescopes could use this innovation to improve the efficiency of existing cryo

  19. In-tank recirculating arsenic treatment system

    DOEpatents

    Brady, Patrick V.; Dwyer, Brian P.; Krumhansl, James L.; Chwirka, Joseph D.

    2009-04-07

    A low-cost, water treatment system and method for reducing arsenic contamination in small community water storage tanks. Arsenic is removed by using a submersible pump, sitting at the bottom of the tank, which continuously recirculates (at a low flow rate) arsenic-contaminated water through an attached and enclosed filter bed containing arsenic-sorbing media. The pump and treatment column can be either placed inside the tank (In-Tank) by manually-lowering through an access hole, or attached to the outside of the tank (Out-of-Tank), for easy replacement of the sorption media.

  20. Our Built and Natural Environments

    EPA Pesticide Factsheets

    Our Built and Natural Environments summarizes research that shows how development patterns affect the environment and human health, and how certain development patterns can reduce the environmental and human health impacts of development.

  1. High speed exhaust gas recirculation valve

    SciTech Connect

    Fensom, Rod; Kidder, David J.

    2005-01-18

    In order to minimize pollutants such as Nox, internal combustion engines typically include an exhaust gas recirculation (EGR) valve that can be used to redirect a portion of exhaust gases to an intake conduit, such as an intake manifold, so that the redirected exhaust gases will be recycled. It is desirable to have an EGR valve with fast-acting capabilities, and it is also desirable to have the EGR valve take up as little space as possible. An exhaust gas recirculation valve is provided that includes an exhaust passage tube, a valve element pivotally mounted within the exhaust passage tube, a linear actuator; and a gear train. The gear train includes a rack gear operatively connected to the linear actuator, and at least one rotatable gear meshing with the rack gear and operatively connected to the valve element to cause rotation of the valve element upon actuation of the linear actuator. The apparatus provides a highly compact package having a high-speed valve actuation capability.

  2. 40 CFR 1065.127 - Exhaust gas recirculation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Exhaust gas recirculation. 1065.127 Section 1065.127 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.127 Exhaust gas recirculation. Use...

  3. 40 CFR 1065.127 - Exhaust gas recirculation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Exhaust gas recirculation. 1065.127 Section 1065.127 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.127 Exhaust gas recirculation. Use...

  4. 40 CFR 1065.127 - Exhaust gas recirculation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Exhaust gas recirculation. 1065.127 Section 1065.127 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.127 Exhaust gas recirculation. Use...

  5. 40 CFR 1065.127 - Exhaust gas recirculation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Exhaust gas recirculation. 1065.127 Section 1065.127 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.127 Exhaust gas recirculation. Use...

  6. 40 CFR 1065.127 - Exhaust gas recirculation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Exhaust gas recirculation. 1065.127 Section 1065.127 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.127 Exhaust gas recirculation. Use...

  7. Energy conservation by partial recirculation of peanut drying air

    SciTech Connect

    Young, J.H.

    1983-06-01

    Conventional, recirculating, and intermittent type peanut dryers were compared in a three-year study. Comparisons indicate that partial recirculation of peanut drying air may reduce energy consumption per unit of water removed by approximately 25% while also reducing required drying time and maintaining high quality.

  8. Energy savings from air recirculation in peanut curing

    SciTech Connect

    Cook, D.F.; Cundiff, J.S.; Vaughan, D.H.

    1982-12-01

    A thin-layer peanut drying simulation model was adapted to incorporate air recirculation. Laboratory crop dryers were designed and constructed to conduct experiments to verify the model. Five batches of peanuts were dried using different recirculation strategies. The model successfully predicted the results.

  9. 21 CFR 880.5045 - Medical recirculating air cleaner.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Medical recirculating air cleaner. 880.5045... (CONTINUED) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Therapeutic Devices § 880.5045 Medical recirculating air cleaner. (a) Identification. A medical...

  10. Measuring the Built Environment for Physical Activity

    PubMed Central

    Brownson, Ross C.; Hoehner, Christine M.; Day, Kristen; Forsyth, Ann; Sallis, James F.

    2009-01-01

    Physical inactivity is one of the most important public health issues in the U.S. and internationally. Increasingly, links are being identified between various elements of the physical—or built—environment and physical activity. To understand the impact of the built environment on physical activity, the development of high-quality measures is essential. Three categories of built environment data are being used: (1) perceived measures obtained by telephone interview or self-administered questionnaires; (2) observational measures obtained using systematic observational methods (audits); and (3) archival data sets that are often layered and analyzed with GIS. This review provides a critical assessment of these three types of built-environment measures relevant to the study of physical activity. Among perceived measures, 19 questionnaires were reviewed, ranging in length from 7 to 68 questions. Twenty audit tools were reviewed that cover community environments (i.e., neighborhoods, cities), parks, and trails. For GIS-derived measures, more than 50 studies were reviewed. A large degree of variability was found in the operationalization of common GIS measures, which include population density, land-use mix, access to recreational facilities, and street pattern. This first comprehensive examination of built-environment measures demonstrates considerable progress over the past decade, showing diverse environmental variables available that use multiple modes of assessment. Most can be considered first-generation measures, so further development is needed. In particular, further research is needed to improve the technical quality of measures, understand the relevance to various population groups, and understand the utility of measures for science and public health. PMID:19285216

  11. NGL recovery being hiked by natural-gasoline recirculation

    SciTech Connect

    Rivas M, M.; Bracho, J.L.; Murray, J.E.

    1997-07-07

    Construction will be completed later this year at two compression plants operated by Lagoven, S.A., to install natural-gasoline recirculation to improve NGL recovery. The project is the result of a study of condensate-stream recirculation and absorber operations at the compression plants Tia Juana 2 (PCTJ-2) and Tia Juana 3 (PCTJ-3), offshore Lake Maracaibo in western Venezuela. The PCTJ-2 and PCTJ-3 gas compression plants have two systems: gas compression and NGL extraction. Previous analysis of the NGL extraction and fractionation processes of Lagoven determined that there are two practical and attractive alternatives for the recirculation of the condensate streams in PCTJ-2 and 3: recirculation of natural gasoline from the Ule LPG plant; recirculation of a conditioned condensate from the de-ethanizer tower of each plant. Both alternatives are discussed. Also described are fractionation capacity, and modifications for adding absorption and fractionation.

  12. Effects of spent liquor recirculation in hydrothermal carbonization.

    PubMed

    Kabadayi Catalkopru, Arzu; Kantarli, Ismail Cem; Yanik, Jale

    2017-02-01

    In this study, the effect of the recirculation of spent liquor from hydrothermal carbonization was investigated depending on the biomass type (grape pomace, orange pomace and poultry litter). The yield and fuel properties of hydrochars and spent liquor characteristics were determined for each recirculation step. By recirculation, mass and energy yields of the hydrochar increased, but their combustion characteristics changed: the ignition temperature and combustion reactivity decreased. The organic and inorganic load of liquor was increased with recirculation number, but not as much as would be expected after the first recycle. It was concluded that the load of organic and inorganic species in spent liquor decreased the leaching of some inorganics and diffusion of the degraded soluble fragments from biomass in the subsequent hydrothermal carbonization. Overall, this study showed that spent liquor recirculation makes the overall hydrothermal carbonization process environmentally friendly.

  13. AP1000 Features Prevent Potential Containment Recirculation Screen Plugging

    SciTech Connect

    Andreychek, Timothy; Anderson, Richard; Schulz, Terry

    2004-07-01

    This paper presents the results of plant design development and evaluations that demonstrate that the AP1000 plant is not subject to potential containment recirculation screen plugging following a loss-of-coolant-accident (LOCA). Following a LOCA in a pressurized water reactor, it is necessary to recirculate water from the containment back into the reactor to maintain long term core cooling. The AP1000 utilizes passive safety systems to provide containment recirculation for long term core cooling following a LOCA. The AP1000 also has non-safety pumps which provide a backup means of providing recirculation. Screens are provided around the recirculation pipes to prevent debris from blocking recirculation flow and core cooling passages. Debris may be generated by the LOCA blowdown from insulation and coatings used inside containment. Even with effective cleanliness programs, there may be some resident debris such as dust and dirt. The potential for plugging the recirculation screens is a current PWR licensing issue. The AP1000 design provides inherent advantages with respect to the potential plugging of containment recirculation screens. These characteristics include prevention of fibrous debris generation, improved debris settling and improved recirculation screen design. Debris settling analysis demonstrates that failure of coatings does not result in debris being transported to the screens before it settles to the floor. Additional analysis also shows that the plant can tolerate conservative amounts of resident debris being transported to the screens. The AP1000 significantly reduces the probability of plugging the containment recirculation screens and significantly reduces inspection and maintenance of coatings used inside containment. (authors)

  14. Design of a High-Reynolds Number Recirculating Water Tunnel

    NASA Astrophysics Data System (ADS)

    Daniel, Libin; Elbing, Brian

    2014-11-01

    An experimental fluid mechanics laboratory focused on turbulent boundary layers, drag reduction techniques, multiphase flows and fluid-structure interactions has recently been established at Oklahoma State University. This laboratory has three primary components; (1) a recirculating water tunnel, (2) a multiphase pipe flow loop, and (3) a multi-scale flow visualization system. The design of the water tunnel is the focus of this talk. The criteria used for the water tunnel design was that it had to produce a momentum-thickness based Reynolds number in excess of 104, negligible flow acceleration due to boundary layer growth, maximize optical access for use of the flow visualization system, and minimize inlet flow non-uniformity. This Reynolds number was targeted to bridge the gap between typical university/commercial water tunnels (103) and the world's largest water tunnel facilities (105) . These objectives were achieved with a 152 mm (6-inch) square test section that is 1 m long and has a maximum flow speed of 10 m/s. The flow non-uniformity was mitigated with the use of a tandem honeycomb configuration, a settling chamber and an 8.5:1 contraction. The design process that produced this final design will be presented along with its current status.

  15. Industrial Energy Conservation, Forced Internal Recirculation Burner

    SciTech Connect

    Joseph Rabovitser

    2003-06-19

    The overall objective of this research project is to develop and evaluate an industrial low NOx burner for existing and new gas-fired combustion systems for intermediate temperature (1400 degree to 2000 degree F) industrial heating devices such as watertube boilers and process fluid heaters. A multi-phase effort is being pursued with decision points to determine advisability of continuance. The current contract over Phases II and III of this work. The objectives of each phase are as follows. Phase II - to design, fabricate, and evaluate prototype burners based on the Forced Internal Recirculation (FIR) concept. Phase III - to evaluate the performance of an FIR burner under actual operating conditions in a full-scale field test and establish the performance necessary for subsequent commercialization

  16. Recirculation bubbler for glass melter apparatus

    DOEpatents

    Guerrero, Hector; Bickford, Dennis

    2007-06-05

    A gas bubbler device provides enhanced recirculation of molten glass within a glass melter apparatus. The bubbler device includes a tube member disposed within a pool of molten glass contained in the melter. The tube member includes a lower opening through which the molten glass enters and upper slots disposed close to (above or below) the upper surface of the pool of molten glass and from which the glass exits. A gas (air) line is disposed within the tube member and extends longitudinally thereof. A gas bubble distribution device, which is located adjacent to the lower end of the tube member and is connected to the lower end of the gas line, releases gas through openings therein so as to produce gas bubbles of a desired size in the molten glass and in a distributed pattern across the tube member.

  17. Recirculating Molten Metal Supply System And Method

    DOEpatents

    Kinosz, Michael J.; Meyer, Thomas N.

    2003-07-01

    The melter furnace includes a heating chamber (16), a pump chamber (18), a degassing chamber (20), and a filter chamber (22). The pump chamber (18) is located adjacent the heating chamber (16) and houses a molten metal pump (30). The degassing chamber (20) is located adjacent and in fluid communication with the pump chamber (18), and houses a degassing mechanism (36). The filter chamber (22) is located adjacent and in fluid communication with the degassing chamber (20). The filter chamber (22) includes a molten metal filter (38). The melter furnace (12) is used to supply molten metal to an externally located holder furnace (14), which then recirculates molten metal back to the melter furnace (12).

  18. Nutrient Management in Recirculating Hydroponic Culture

    NASA Technical Reports Server (NTRS)

    Bugbee, Bruce

    2004-01-01

    There is an increasing need to recirculate and reuse nutrient solutions in order to reduce environmental and economic costs. However, one of the weakest points in hydroponics is the lack of information on managing the nutrient solution. Many growers and research scientists dump out nutrient solutions and refill at weekly intervals. Other authors have recommended measuring the concentrations of individual nutrients in solution as a key to nutrient control and maintenance. Dumping and replacing solution is unnecessary. Monitoring ions in solution is not always necessary; in fact the rapid depletion of some nutrients often causes people to add toxic amounts of nutrients to the solution. Monitoring ions in solution is interesting, but it is not the key to effective maintenance.

  19. The House That Putin Built

    DTIC Science & Technology

    2005-06-01

    BUILT by Claudine Caluori June 2005 Thesis Co-Advisors: Anne Clunan Robert Looney THIS...Claudine Caluori Approved by: Anne Clunan Thesis Co-Advisor Robert Looney Thesis Co-Advisor Douglas Porch Chairman, Department of...Remington, Politics in Russia, (New York: Pearson Education, Inc. 2004), 49. 3 Robert D. English, Russia and the Idea of the West: Chapter 6: The New

  20. Schools Built with Fallout Shelter.

    ERIC Educational Resources Information Center

    Office of Civil Defense (DOD), Washington, DC.

    Fallout protection can be built into a school building with little or no additional cost, using areas that are in continual use in the normal functioning of the building. A general discussion of the principles of shelter design is given along with photographs, descriptions, drawings, and cost analysis for a number of recently constructed schools…

  1. Recirculating planar magnetrons: simulations and experiment

    SciTech Connect

    Franzi, Matthew; Gilgenbach, Ronald; French, David; Lau, Y.Y.; Simon, David; Hoff, Brad; Luginsland, John W.

    2011-07-01

    The Recirculating Planar Magnetron (RPM) is a novel crossed-field device whose geometry is expected to reduce thermal load, enhance current yield as well as ease the geometric limitations in scaling to high RF frequencies as compared to the conventional cylindrical magnetrons. The RPM has two different adaptations: A. Axial B field and radial E field; B. Radial B field and axial E field. The preliminary configuration (A) to be used in experiments at the University of Michigan consists of two parallel planar sections which join on either end by cylindrical regions to form a concentric extruded ellipse. Similar to conventional magnetrons, a voltage across the AK gap in conjunction with an axial magnetic field provides the electrons with an ExB drift. The device is named RPM because the drifting electrons recirculate from one planar region to the other. The drifting electrons interact with the resonantly tuned slow wave structure on the anode causing spoke formation. These electron spokes drive a RF electric field in the cavities from which RF power may be extracted to Waveguides. The RPM may be designed in either a conventional configuration with the anode on the outside, for simplified extraction, or as an inverted magnetron with the anode at the inner conductor, for fast start-up. Currently, experiments at the Pulsed Power and Microwave Laboratory at the University of Michigan are in the setup and design phase. A conventional RPM with planar cavities is to be installed on the Michigan Electron Long Beam Accelerator (MELBA) and is anticipated to operate at -200kV, 0.2T with a beam current of 1-10 kA at 1GHz. The conventional RPM consists of 12 identical planar cavities, 6 on each planar side, with simulated quality factor of 20.

  2. Progress toward a prototype recirculating ion induction accelerator

    SciTech Connect

    Friedman, A.; Barnard, J.J.; Cable, M.D.

    1996-06-01

    The U.S. Inertial Fusion Energy (IFE) Program is developing the physics and technology of ion induction accelerators, with the goal of electric power production by means of heavy ion beam-driven inertial fusion (commonly called heavy ion fusion, or HIF). Such accelerators are the principal candidates for inertial fusion power production applications, because they are expected to enjoy high efficiency, inherently high pulse repetition frequency (power plants are expected to inject and burn several fusion targets per second), and high reliability. In addition (and in contrast with laser beams, which are focused with optical lenses) heavy-ion beams will be focused onto the target by magnetic fields, which cannot be damaged by target explosions. Laser beams are used in present-day and planned near-term facilities (such as LLNUs Nova and the National Ignition Facility, which is being designed) because they can focus beams onto very small, intensely illuminated spots for scaled experiments and because the laser technology is already available. An induction accelerator works by passing the beam through a series of accelerating modules, each of which applies an electromotive force to the beam as it goes by; effectively, the beam acts as the secondary winding of a series of efficient one-turn transformers. The authors present plans for and progress toward the development of a small (4.5-m-diam) prototype recirculator, which will accelerate singly charged potassium ions through 15 laps, increasing the ion energy from 80 to 320 keV and the beam current from 2 to 8 mA. Beam confinement and bending are effected with permanent-magnet quadrupoles and electric dipoles, respectively. The design is based on scaling laws and on extensive particle and fluid simulations of the behavior of the space charge-dominated beam.

  3. Study of atmospheric stagnation, recirculation and ventilation potential at Narora Atomic Power Station NPP site.

    PubMed

    Kumar, Deepak; Kumar, Avinash; Kumar, Vimal; Kumar, Jaivender; Ravi, P M

    2013-04-01

    The atmosphere is an important pathway to be considered in assessment of the environmental impact of radioactivity releases from nuclear facilities. The estimation of concentration of released effluents in air and possible ground contamination needs an understanding of relevant atmospheric dispersion. This paper describes the meteorological characteristics of Narora Atomic Power Station (NAPS) Nuclear Power Project site by using the integral parameters developed by Allwine and Whiteman (Atmospheric Environment 28(4):713-721, 1994). Meteorological data measured during the period 2006-2010 were analysed. The integral quantities related to the occurrence of stagnation, recirculation and ventilation characteristics were studied for the NAPS site to assess the dilution potential of the atmosphere. Wind run and recirculation factors were calculated for a 24-h transport time using 5 years of hourly surface measurements of wind speed and direction. The occurrence of stagnation, recirculation and ventilation characteristics during 2006-2010 at the NAPS site is observed to be 33.8, 19.5 and 34.7 % of the time, respectively. The presence of strong winds with predominant wind direction NW and WNW during winter and summer seasons leads to higher ventilation (48.1 and 44.3 %) and recirculation (32.6 % of the summer season). The presence of more dispersed light winds during pre-winter season with predominant wind directions W and WNW results in more stagnation (59.7 % of the pre-winter season). Thus, this study will serve as an essential meteorological tool to understand the transport mechanism of atmospheric radioactive effluent release from any nuclear industry during the pre-operational as well as operational phase.

  4. Recirculating Beam Breakup Study for the 12 GeV Upgrade at Jefferson Lab

    SciTech Connect

    Ilkyoung Shin, Todd Satogata, Shahid Ahmed, Slawomir Bogacz, Mircea Stirbet, Haipeng Wang, Yan Wang, Byung Yunn, Ryan Bodenstein

    2012-07-01

    Two new high gradient C100 cryomodules with a total of 16 new cavities were installed at the end of the CEBAF south linac during the 2011 summer shutdown as part of the 12-GeV upgrade project at Jefferson Lab. We surveyed the higher order modes (HOMs) of these cavities in the Jefferson Lab cryomodule test facility and CEBAF tunnel. We then studied recirculating beam breakup (BBU) in November 2011 to evaluate CEBAF low energy performance, measure transport optics, and evaluate BBU thresholds due to these HOMs. This paper discusses the experiment setup, cavity measurements, machine setup, optics measurements, and lower bounds on BBU thresholds by new cryomodules.

  5. Exhaust gas recirculation method for internal combustion engines

    SciTech Connect

    Kawanabe, T.; Kimura, K.; Asakura, M.; Shiina, T.

    1988-07-19

    This patent describes a method of controlling exhaust gas recirculation in an internal combustion engine having an exhaust passage, an intake passage, an exhaust gas recirculating passage communicating the exhaust passage with the intake passage, and exhaust gas recirculating valve; and a transmission having a shift lever. The valve opening of the exhaust gas recirculating valve is controlled in response to operating conditions of the engine so as to regulate the amount of exhaust gas recirculation to values appropriate to the operating conditions of the engine. The method comprising the steps of (1) determining whether or not the engine is in at least one of a predetermined accelerating condition and a predetermined decelerating condition; (2) varying the valve opening of the exhaust gas recirculating valve by a predetermined value when the engine is determined to be in at least one of the predetermined accelerating condition and the predetermined decelerating condition; (3) detecting a position of the shift lever of the transmission; and (4) correcting the predetermined value in accordance with the detected position of the shift lever so as to increase the valve opening of the exhaust gas recirculating valve as the shift lever of the transmission is set to a higher speed position.

  6. Built Environment Wind Turbine Roadmap

    SciTech Connect

    Smith, J.; Forsyth, T.; Sinclair, K.; Oteri, F.

    2012-11-01

    The market currently encourages BWT deployment before the technology is ready for full-scale commercialization. To address this issue, industry stakeholders convened a Rooftop and Built-Environment Wind Turbine Workshop on August 11 - 12, 2010, at the National Wind Technology Center, located at the U.S. Department of Energy’s National Renewable Energy Laboratory in Boulder, Colorado. This report summarizes the workshop.

  7. Production of market-size North American strain Atlantic salmon Salmo salar in a land-based recirculation aquaculture system using freshwater

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is interest in culturing Atlantic salmon Salmo salar to market-size in land-based, closed containment systems that use recirculation aquaculture systems (RAS), as this technology often enables facilities to locate near major markets, obtain permits, exclude obligate pathogens, and/or reduce en...

  8. Eddy-driven recirculation of Atlantic Water in Fram Strait

    NASA Astrophysics Data System (ADS)

    Hattermann, Tore; Isachsen, Pâl. Erik; Appen, Wilken-Jon; Albretsen, Jon; Sundfjord, Arild

    2016-04-01

    Eddy-resolving regional ocean model results in conjunction with synthetic float trajectories and observations provide new insights into the recirculation of the Atlantic Water (AW) in Fram Strait that significantly impacts the redistribution of oceanic heat between the Nordic Seas and the Arctic Ocean. The simulations confirm the existence of a cyclonic gyre around the Molloy Hole near 80°N, suggesting that most of the AW within the West Spitsbergen Current recirculates there, while colder AW recirculates in a westward mean flow south of 79°N that primarily relates to the eastern rim of the Greenland Sea Gyre. The fraction of waters recirculating in the northern branch roughly doubles during winter, coinciding with a seasonal increase of eddy activity along the Yermak Plateau slope that also facilitates subduction of AW beneath the ice edge in this area.

  9. Engine with pulse-suppressed dedicated exhaust gas recirculation

    SciTech Connect

    Keating, Edward J.; Baker, Rodney E.

    2016-06-07

    An engine assembly includes an intake assembly, a spark-ignited internal combustion engine, and an exhaust assembly. The intake assembly includes a charge air cooler disposed between an exhaust gas recirculation (EGR) mixer and a backpressure valve. The charge air cooler has both an inlet and an outlet, and the back pressure valve is configured to maintain a minimum pressure difference between the inlet of the charge air cooler and an outlet of the backpressure valve. A dedicated exhaust gas recirculation system is provided in fluid communication with at least one cylinder and with the EGR mixer. The dedicated exhaust gas recirculation system is configured to route all of the exhaust gas from the at least one cylinder to the EGR mixer for recirculation back to the engine.

  10. Pulsed Magnet Arc Designs for Recirculating Linac Muon Accelerators

    SciTech Connect

    K.B. Beard, R.P. Johnson, S.A. Bogacz, G.M. Wang

    2009-05-01

    Recirculating linear accelerators (RLAs) using both pulsed quadrupoles and pulsed dipoles can be used to quickly accelerate muons in the 3 – 2000 GeV range. Estimates on the requirements for the pulsed quadrupoles and dipoles are presented.

  11. Future of recirculating systems in the US aquaculture industry

    SciTech Connect

    Malone, R.F.

    1994-08-01

    Recirculating systems consist of a culture unit, a recirculating pump, and a treatment block which facilitate extended re-use of water in the rearing of aquatic animals. As water re-use is extended from a few hours to months or even years, the complexity of the treatment block increases. Classified as either `open` with greater than 10 percent water replacement per day or `closed` with less than 10 percent daily replacement, most recirculating systems include aerators, clarifiers, and biofilters as key core elements. The aquaculture industry is increasingly facing a variety of socio-economic issues which will dramatically influence its future development. These problems range from increased competition for water rights through price depression and foreign imports to predation by protected migratory birds. As water-use, environmental, and conservation conflicts grow, the cost differences between the flow-through and closed production technologies will narrow, increasing the industry`s use of recirculating systems.

  12. A closed recirculated sea-water system

    USGS Publications Warehouse

    1967-01-01

    Study of a virus disease in the chinook salmon (Oncorhynchus tshawytscha) necessitated the use of a marine environment to study the long range effects of the disease and to complete the life cycle of its etiologic agent. A closed recirculated sea-water system was designed for use under experimental laboratory conditions so that controlled studies of the disease could be made. As others may wish to do marine environment studies in the laboratory, the design and operation of our system are presented. Other systems currently in use have been described by Chin (1959), DeWitt and Salo (1960), McCrimmon and Berst (1966), and the authors of collected papers edited by Clark and Clark (1964). Preparatory to the design and construction of the system in use in this laboratory, visits were made to marine systems in use at the University of Washington's College of Fisheries, Seattle, -washington, and Friday Harbor Laboratory, San Juan Island, Washington; the Washington State Department of Fisheries' Point whitney Shellfish Laboratory, Brinnon, Washington; Humboldt State College, Arcata, California; and the Steinhart Aquarium of the California Academy of Science, San Francisco, California.

  13. Demonstration of Spray Booth Recirculation and Partitioning - Phase II

    DTIC Science & Technology

    1996-01-01

    electrostatic paint spray enclosures, such as the high volume, low pressure ( HVLP ) systems employed at Barstow MCLB, a minimum linear velocity of 100 fpm must be...SUBTITLE 5. FUNDING NUMBERS Demonstration of Spray Booth Recirculation and Partitioning - Phase II N/A 6. AUTHOR(S) D. Proffitt, R.K. Clayton, & J...ANSI Std. Z39-18 298-102 * , 85-1996 Demonstration of Spray Booth Recirculation and Partitioning - Phase II David Proffitt and Russell K. Clayton

  14. LONGITUDINAL REFERENCE PARTICLE MOTION IN NEARLY ISOCHRONOUS FFAG RECIRCULATING ACCELERATORS.

    SciTech Connect

    BERG,J.S.

    2001-07-01

    A Fixed Field Alternating Gradient (FFAG) arc can be used to reduce the cost of a recirculating accelerator. Path length variation with energy in such an arc can limit its usefulness, however, due to phase offset at the linac. This paper examines the dynamics of the reference particle in an FFAG recirculating accelerator, and describes the limitations on the design because of path length variation with energy.

  15. The Pebble Recirculation Experiment (PREX) for the AHTR

    SciTech Connect

    Bardet, P.; An, J.Y.; Franklin, J.T.; Huang, D.; Lee, K.; Mai, A.; Toulouse, M.; Peterson, P.F.

    2007-07-01

    Conceptual design studies for the liquid-salt cooled Advanced High Temperature Reactor (AHTR) have identified three candidate TRISO fuel geometries: prismatic, pebble, and stringer fuels. This paper presents experimental results from the integral Pebble Recirculation Experiment (PREX) that verifies the viability of pebble recirculation in a Pebble Bed AHTR (PB-AHTR). The experiments conducted include injection and extraction of buoyant pebbles, measurements of packing density and pressure losses, and observations of pebble landing dynamics and bed formation. (authors)

  16. Antral recirculation in the stomach during gastric mixing.

    PubMed

    Imai, Yohsuke; Kobayashi, Ikuma; Ishida, Shunichi; Ishikawa, Takuji; Buist, Martin; Yamaguchi, Takami

    2013-03-01

    We investigate flow in the stomach during gastric mixing using a numerical simulation with an anatomically realistic geometry and free-surface flow modeling. Because of momentum differences between greater and lesser curvatures during peristaltic contractions, time-averaged recirculation is generated in the antrum, with retropulsive flow away from the pylorus and compensation flow along the greater curvature toward the pylorus. Gastric content in the distal stomach is continuously transported to the distal antrum by the forward flow of antral recirculation, and it is then mixed by the backward retropulsive flow. Hence, the content inside the antral recirculation is well mixed independently of initial location, whereas the content outside the recirculation is poorly mixed. Free-surface modeling enables us to analyze the effects of posture on gastric mixing. In the upright, prone, and right lateral positions, most of the antrum is filled with content, and the content is well mixed by antral recirculation. In contrast, in the supine and left lateral positions, most of the content is located outside antral recirculation, which results in poor mixing. The curved, twisted shape of the stomach substantially supports gastric mixing in fluid mechanical terms.

  17. XLR 500i: recirculating ring ArF light source for immersion lithography

    NASA Astrophysics Data System (ADS)

    Brown, D. J. W.; O'Keeffe, P.; Fleurov, V. B.; Rokitski, R.; Bergstedt, R.; Fomenkov, I. V.; O'Brien, K.; Farrar, N. R.; Partlo, W. N.

    2007-03-01

    As Argon Fluoride (ArF) lithography moves into high volume production, ArF light sources need to meet performance requirements beyond the traditional drivers of power and bandwidth. The first key requirement is a continuous decrease in Cost of Ownership (CoO) where the industry requirement is for reduction in ArF CoO in line with the historical cost reduction demonstrated for Krypton Fluoride (KrF) light sources. A second requirement is improved light source performance stability. As CD control requirements shrink, following the ITRS roadmap, all process parameters which affect CD variation need tighter control. In the case of the light source, these include improved control of bandwidth, pulse energy stability and wavelength. In particular, CD sensitivity to exposure dose has become a serious challenge for device processing and improvements to laser pulse energy stability can contribute to significantly better dose control. To meet these performance challenges Cymer has designed a new dual chamber laser architecture. The Recirculating Ring design requires 10X less energy from the Master Oscillator (MO). This new configuration enables the MO chamber lifetime to reach that of the power amplifier chamber at around 30Bp. In addition, other optical modules in the system such as the line narrowing module experience lower light intensity, ensuring even longer optics lifetime. Furthermore, the Recirculating Ring configuration operates in much stronger saturation. MO energy instabilities are reduced by a factor of 9X when passed through the Ring. The output energy stability exhibits the characteristics of a fully saturated amplifier and pulse energy stability improvement of 1.5X is realized. This performance enables higher throughput scanner operation with enhanced dose control. The Recirculating Ring technology will be introduced on the XLR 500i, Cymer's fifth-generation dual chamber-based light source built on the production-proven XLA platform. This paper will describe

  18. Built environment and wellbeing in Italian psychiatric wards.

    PubMed

    Plantamura, Francesca; Capolongo, Stefano; Oberti, Ilaria

    2015-01-01

    The healthcare built environment has effects on patient's wellbeing. These effects are even heavier on sensitive patient such as psychiatric ones. Therefore the environment design can be a key factor in promoting the patients' well-being and the care process. This paper investigates how this vision is influencing the design of psychiatric facilities in the Italian context, known for its radical innovation of mental health services due to Law 180 (1978). The article identifies the current built environment issues of the psychiatric ward, the design indications available and the possible future actions to meet the needs of users and to improve wellbeing and care process.

  19. Built-Environment Report Summary

    SciTech Connect

    Baring-Gould, Ian; Fields, Jason; Preus, Robert; Oteri, Frank

    2016-06-14

    Built-environment wind turbine (BEWT) projects are wind energy projects that are constructed on, in, or near buildings. These projects present an opportunity for distributed, low-carbon generation combined with highly visible statements on sustainability, but the BEWT niche of the wind industry is still developing and is relatively less mature than the utility-scale wind or conventional ground-based distributed wind sectors. The findings presented in this presentation cannot be extended to wind energy deployments in general because of the large difference in application and technology maturity. This presentation summarizes the results of a report investigating the current state of the BEWT industry by reviewing available literature on BEWT projects as well as interviewing project owners on their experiences deploying and operating the technology. The authors generated a series of case studies that outlines the pertinent project details, project outcomes, and lessons learned.

  20. Case study of controlled recirculation at a Wyoming trona mine

    PubMed Central

    Pritchard, C.; Scott, D.; Frey, G.

    2015-01-01

    Controlled recirculation has been used in the metal/nonmetal mining industry for energy savings when heating and cooling air, in undersea mining and for increasing airflow to mining areas. For safe and effective use of controlled district recirculation, adequate airflow to dilute contaminants must exist prior to implementation, ventilation circuit parameters must be accurately quantified, ventilation network modeling must be up to date, emergency planning scenarios must be performed and effective monitoring and control systems must be installed and used. Safety and health issues that must be considered and may be improved through the use of controlled district recirculation include blasting fumes, dust, diesel emissions, radon and contaminants from mine fires. Controlled recirculation methods are expected to become more widely used as mines reach greater working depths, requiring that these health and safety issues be well understood. The U.S. National Institute for Occupational Safety and Health (NIOSH) conducted two controlled recirculation tests over three days at a Wyoming trona mine, utilizing an inline booster fan to improve airflow to a remote and difficult-to-ventilate development section. Test results were used to determine the effect that recirculation had on air qualities and quantities measured in that section and in other adjacent areas. Pre-test conditions, including ventilation quantities and pressures, were modeled using VnetPC. During each test, ventilation quantities and pressures were measured, as well as levels of total dust. Sulfur hexafluoride (SF6) tracer gas was used to simulate a mine contaminant to monitor recirculation wave cycles. Results showed good correlation between the model results and measured values for airflows, pressure differentials, tracer gas arrival times, mine gasses and dust levels. PMID:26251567

  1. Cannula Design and Recirculation During Venovenous Extracorporeal Membrane Oxygenation

    PubMed Central

    Palmér, Oscar; Palmér, Kenneth; Hultman, Jan

    2016-01-01

    Extracorporeal membrane oxygenation (ECMO) is used as a lifesaving rescue treatment in refractory respiratory or cardiac failure. During venovenous (VV) ECMO, the presence of recirculation is known, but quantification and actions to minimize recirculation after measurement are to date not routinely practiced. In the current study, we investigated the effect of draining cannula design on recirculation fraction (Rf) during VV ECMO; conventional mesh cannula was compared with a multistage cannula. The effect of adjusting cannula position was also studied. Recirculation was measured with ultrasound dilution technique at different ECMO flows and after cannula repositioning. All patients who were admitted to our unit between October 2014 and July 2015 catheterized by the atrio-femoral single lumen method were included. A total of 108 measurements were conducted in 14 patients. The multistage cannula showed significantly less recirculation (19.0 ± 12.2%) compared with the conventional design (38.0 ± 13.7). Pooled data in cases improved from adjustment showing reduced Rf by 7%. In conclusion, the choice of cannula matters, as does adjustment of the draining cannula position during atrio-femoral VV ECMO. By utilizing the ultrasound dilution technique to measure Rf before and after repositioning, effective ECMO flow can be improved for a more effective ECMO treatment. PMID:27660904

  2. Smart built-in test

    NASA Astrophysics Data System (ADS)

    Richards, Dale W.

    1990-03-01

    The work which built-in test (BIT) is asked to perform in today's electronic systems increases with every insertion of new technology or introduction of tighter performance criteria. Yet the basic purpose remains unchanged -- to determine with high confidence the operational capability of that equipment. Achievement of this level of BIT performance requires the management and assimilation of a large amount of data, both realtime and historical. Smart BIT has taken advantage of advanced techniques from the field of artificial intelligence (AI) in order to meet these demands. The Smart BIT approach enhances traditional functional BIT by utilizing AI techniques to incorporate environmental stress data, temporal BIT information and maintenance data, and realtime BIT reports into an integrated test methodology for increased BIT effectiveness and confidence levels. Future research in this area will incorporate onboard fault-logging of BIT output, stress data and Smart BIT decision criteria in support of a singular, integrated and complete test and maintenance capability. The state of this research is described along with a discussion of directions for future development.

  3. Smart built-in test

    NASA Technical Reports Server (NTRS)

    Richards, Dale W.

    1990-01-01

    The work which built-in test (BIT) is asked to perform in today's electronic systems increases with every insertion of new technology or introduction of tighter performance criteria. Yet the basic purpose remains unchanged -- to determine with high confidence the operational capability of that equipment. Achievement of this level of BIT performance requires the management and assimilation of a large amount of data, both realtime and historical. Smart BIT has taken advantage of advanced techniques from the field of artificial intelligence (AI) in order to meet these demands. The Smart BIT approach enhances traditional functional BIT by utilizing AI techniques to incorporate environmental stress data, temporal BIT information and maintenance data, and realtime BIT reports into an integrated test methodology for increased BIT effectiveness and confidence levels. Future research in this area will incorporate onboard fault-logging of BIT output, stress data and Smart BIT decision criteria in support of a singular, integrated and complete test and maintenance capability. The state of this research is described along with a discussion of directions for future development.

  4. Built-in self test

    NASA Astrophysics Data System (ADS)

    Jansen, B.; Vandegoor, A. J.

    1988-11-01

    Because of the increasing complexity of digital circuits, it is becoming more and more difficult to determine whether a circuit is correct or faulty. Faults in a circuit can hardly be detected just by looking at the outside what the reaction of the circuit is to a certain input sequence. Fault tolerant computing can be a solution. Built-In Self Test (BIST) techniques can also be used to verify whether the circuit is correct, not only during normal operation, but also during the early development periods. The result of using BIST techniques is a considerable reduction of time between design and the final product, and a reduction of maintenance time and cost. BIST is a test method of which the circuit can separate itself from the surrounding logic, and perform a test. After the self test, the circuit reports to the surrounding logic whether it is correct. The advantage of BIST is that it is a universal and systematic test method with a solid mathematical foundation. Based on the stuck-at fault model, it is possible to compute the fault coverage, which is the number of faults detected by the BIST method. The theory of BIST is described. A circuit is divided into combinational and sequential parts, which are tested separately. The sequential parts are tested with a so-called scan-path test. Alternative test methods to test the combinational parts are described. The method to compute the number of patterns needed to detect all faults with a certain probability as function of complexity of the circuit is given. The theory of CRC signature analyzers, and the probability of masking are also described and illustrated with some examples, which can directly be used in practice.

  5. Acceleration schedules for a recirculating heavy-ion accelerator

    SciTech Connect

    Sharp, W.M.; Grote, D.P.

    2002-05-01

    Recent advances in solid-state switches have made it feasible to design programmable, high-repetition-rate pulsers for induction accelerators. These switches could lower the cost of recirculating induction accelerators, such as the ''small recirculator'' at Lawrence Livermore National Laboratory (LLNL), by substantially reducing the number of induction modules. Numerical work is reported here to determine what effects the use of fewer pulsers at higher voltage would have on the beam quality of the LLNL small recirculator. Lattices with different numbers of pulsers are examined using the fluid/envelope code CIRCE, and several schedules for acceleration and compression are compared for each configuration. For selected schedules, the phase-space dynamics is also studied using the particle-in-cell code WARP3d.

  6. Hydrothermal carbonization: process water characterization and effects of water recirculation.

    PubMed

    Stemann, Jan; Putschew, Anke; Ziegler, Felix

    2013-09-01

    Poplar wood chips were treated hydrothermally and the increase of process efficiency by water recirculation was examined. About 15% of the carbon in the biomass was dissolved in the liquid phase when biomass was treated in de-ionized water at 220 °C for 4 h. The dissolved organic matter contained oxygen and was partly aerobically biodegradable. About 30-50% of the total organic carbon originated from organic acids. A polar and aromatic fraction was extracted and a major portion of the organic load was of higher molecular weight. By process water recirculation organic acids in the liquid phase concentrated and catalyzed dehydration reactions. As a consequence, functional groups in hydrothermally synthesized coal declined and dewaterability was enhanced. Recirculated reactive substances polymerized and formed additional solid substance. As a result, carbon and energetic yields of the produced coal rose to 84% and 82%, respectively.

  7. Boosting devices with integral features for recirculating exhaust gas

    DOEpatents

    Wu, Ko-Jen

    2015-12-22

    According to one embodiment of the invention, a turbine housing includes a turbine inlet in fluid communication with a turbine volute configured to house a turbine wheel, the turbine inlet configured to direct an exhaust gas flow from an engine to the turbine wheel. The turbine housing also includes a turbine outlet in fluid communication with the turbine volute, the turbine outlet configured to direct the exhaust gas flow to an exhaust gas conduit and a first exhaust gas recirculation supply port located on and in fluid communication with the turbine outlet, the first exhaust gas recirculation supply port being configured to direct a portion of the exhaust gas flow to an exhaust gas recirculation supply conduit.

  8. A fuel cell balance of plant test facility

    NASA Astrophysics Data System (ADS)

    Dicks, A. L.; Martin, P. A.

    Much attention is focused in the fuel cell community on the development of reliable stack technology, but to successfully exploit fuel cells, they must form part of integrated power generation systems. No universal test facilities exist to evaluate SOFC stacks and comparatively little research has been undertaken concerning the issues of the rest of the system, or balance of plant (BOP). BG, in collaboration with Eniricerche, has therefore recently designed and built a test facility to evaluate different configurations of the BOP equipment for a 1-5 kWe solid oxide fuel cell (SOFC) stack. Within this BOP project, integrated, dynamic models have been developed. These have shown that three characteristic response times exist when the stack load is changed and that three independent control loops are required to manage the almost instantaneous change in power output from an SOFC stack, maintain the fuel utilisation and control the stack temperature. Control strategies and plant simplifications, arising from the dynamic modelling, have also been implemented in the BOP test facility. An SOFC simulator was designed and integrated into the control system of the test rig to behave as a real SOFC stack, allowing the development of control strategies without the need for a real stack. A novel combustor has been specifically designed, built and demonstrated to be capable of burning the low calorific anode exhaust gas from an SOFC using the oxygen depleted cathode stream. High temperature, low cost, shell and tube heat exchangers have been shown to be suitable for SOFC systems. Sealing of high temperature anode recirculation fans has, however, been shown to be a major issue and identified as a key area for further investigation.

  9. Envelope model of a heavy-ion recirculator

    SciTech Connect

    Sharp, W.M.; Barnard, J.J.; Yu, S.S.

    1990-12-01

    A simple transport code has been developed to model the beam in a heavy-ion recirculating accelerator. The novel feature of the model is the treatment of the beam charge density as a Lagrangian fluid in the axial direction. In addition, the envelope and centroid equations include terms that account for the transverse self-force, image forces, and bend fields in the paraxial limit. The use of compressible'' beam slices makes the code suitable for designing the acceleration and compression schedules. The code has been used primarily to design the lattice of the LLNL recirculator, and preliminary magnet configurations for that machine are presented here. 3 refs., 2 figs.

  10. A recirculating cooling system for improved topical cardiac hypothermia.

    PubMed

    Rosenfeldt, F L; Fambiatos, A; Pastoriza-Pinol, J; Stirling, G R

    1981-10-01

    A simple system is described that recirculates cooling fluid for topical cardiac hypothermia. This disposable system can produce a flow of 1,500 ml/min at 2 degrees to 4 degrees C. The recirculating cooler produced significantly lower myocardial temperatures than a conventional fluid-discard system in 22 patients having coronary operation. This system has been used as part of the technique of hypothermic cardioplegia in more than 600 patients. During various cardiac procedures, septal temperatures were maintained well below 20 degrees C for 60 minutes or more without the need to reinfuse the cardioplegic solution.

  11. Boosting devices with integral features for recirculating exhaust gas

    DOEpatents

    Wu, Ko -Jen

    2015-09-15

    According to one embodiment of the invention, a compressor housing includes a compressor inlet in fluid communication with a compressor volute configured to house a compressor wheel, the compressor inlet configured to provide a first air flow to the compressor wheel and a compressor outlet in fluid communication with the compressor volute, the compressor outlet configured to direct a compressed gas to an intake manifold. The compressor housing further includes an exhaust gas recirculation inlet port in fluid communication with the compressor volute, the exhaust gas recirculation inlet port being configured to combine an exhaust gas flow with the air flow to the compressor wheel.

  12. In-tank aeration, a necessary compliment of loaded systems in an airlift recirculating aquaculture system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water treatment components in recirculating aquaculture systems in generally address solids removal, nitrification, circulation, aeration, and degasification. Airlift pumps in a recirculating aquaculture system can address water circulation, aeration, and degasification. Recent data indicates oxygen...

  13. Towards Non-thrombogenic Performance of Blood Recirculating Devices

    PubMed Central

    Bluestein, D.; Chandran, K. B.; Manning, K. B.

    2010-01-01

    Implantable blood recirculating devices have provided life saving solutions to patients with severe cardiovascular diseases. However, common problems of hemolysis and thromboembolism remain an impediment to these devices. In this article, we present a brief review of the work by several groups in the field that has led to the development of new methodologies that may facilitate achieving the daunting goal of optimizing the thrombogenic performance of blood recirculating devices. The aim is to describe work which pertains to the interaction between flow-induced stresses and the blood constituents, and that supports the hypothesis that thromboembolism in prosthetic blood recirculating devices is initiated and maintained primarily by the non-physiological flow patterns and stresses that activate and enhance the aggregation of blood platelets, increasing the risk of thromboembolism and cardioembolic stroke. Such work includes state-of-the-art numerical and experimental tools used to elucidate flow-induced mechanisms leading to thromboembolism in prosthetic devices. Following the review, the paper describes several efforts conducted by some of the groups active in the field, and points to several directions that should be pursued in the future in order to achieve the goal for blood recirculating prosthetic devices becoming more effective as destination therapy in the future. PMID:20131098

  14. 33 CFR 159.127 - Safety coliform count: Recirculating devices.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Safety coliform count: Recirculating devices. 159.127 Section 159.127 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing §...

  15. 33 CFR 159.127 - Safety coliform count: Recirculating devices.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Safety coliform count: Recirculating devices. 159.127 Section 159.127 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing §...

  16. 33 CFR 159.127 - Safety coliform count: Recirculating devices.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Safety coliform count: Recirculating devices. 159.127 Section 159.127 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing §...

  17. 33 CFR 159.127 - Safety coliform count: Recirculating devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety coliform count: Recirculating devices. 159.127 Section 159.127 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing §...

  18. 33 CFR 159.127 - Safety coliform count: Recirculating devices.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Safety coliform count: Recirculating devices. 159.127 Section 159.127 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing §...

  19. Recirculation and growth of raindrops in simulated shallow cumulus

    NASA Astrophysics Data System (ADS)

    Naumann, A. K.; Seifert, A.

    2016-06-01

    This study investigates growth processes of raindrops and the role of recirculation of raindrops for the formation of precipitation in shallow cumulus. Two related cases of fields of lightly precipitating shallow cumulus are simulated using Large-Eddy Simulation combined with a Lagrangian drop model for raindrop growth and a cloud tracking algorithm. Statistics from the Lagrangian drop model yield that most raindrops leave the cloud laterally and then evaporate in the subsaturated cloud environmental air. Only 1%-3% of the raindrops contribute to surface precipitation. Among this subsample of raindrops that contribute to surface precipitation, two growth regimes are identified: those raindrops that are dominated by accretional growth from cloud water, and those raindrops that are dominated by selfcollection among raindrops. The mean cloud properties alone are not decisive for the growth of an individual raindrop but the in-cloud variability is crucial. Recirculation of raindrops is found to be common in shallow cumulus, especially for those raindrops that contribute to surface precipitation. The fraction of surface precipitation that is attributed to recirculating raindrops differs from cloud to cloud but can be larger than 50%. This implies that simple conceptual models of raindrop growth that neglect the effect of recirculation disregard a substantial portion of raindrop growth in shallow cumulus.

  20. Confined Turbulent Swirling Recirculating Flow Predictions. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Abujelala, M. T.

    1984-01-01

    Turbulent swirling flow, the STARPIC computer code, turbulence modeling of turbulent flows, the k-xi turbulence model and extensions, turbulence parameters deduction from swirling confined flow measurements, extension of the k-xi to confined swirling recirculating flows, and general predictions for confined turbulent swirling flow are discussed.

  1. In Situ Biotreatment of TBA with Recirculation/Oxygenation

    PubMed Central

    North, Katharine P.; Mackay, Douglas M.; Kayne, Julian S.; Petersen, Daniel; Rasa, Ehsan; Rastegarzadeh, Laleh; Holland, Reef B.; Scow, Kate M.

    2012-01-01

    The potential for in situ biodegradation of tert-butyl alcohol (TBA) by creation of aerobic conditions in the subsurface with recirculating well pairs was investigated in two field studies conducted at Vandenberg Air Force Base (VAFB). In the first experiment, a single recirculating well pair with bromide tracer and oxygen amendment successfully delivered oxygen to the subsurface for 42 days. TBA concentrations were reduced from approximately 500 μg/L to below the detection limit within the treatment zone and the treated water was detected in a monitoring transect several meters downgradient. In the second experiment, a site-calibrated model was used to design a double recirculating well pair with oxygen amendment, which successfully delivered oxygen to the subsurface for 291 days and also decreased TBA concentrations to below the detection limit. Methylibium petroleiphilum strain PM1, a known TBA-degrading bacterium, was detectable at the study site but addition of oxygen had little impact on the already low baseline population densities, suggesting that there was not enough carbon within the groundwater plume to support significant new growth in the PM1 population. Given favorable hydrogeologic and geochemical conditions, the use of recirculating well pairs to introduce dissolved oxygen into the subsurface is a viable method to stimulate in situ biodegradation of TBA or other aerobically-degradable aquifer contaminants. PMID:23358537

  2. Use of low temperature blowers for recirculation of hot gases

    DOEpatents

    Maru, H.C.; Forooque, M.

    1982-08-19

    An apparatus is described for maintaining motors at low operating temperatures during recirculation of hot gases in fuel cell operations and chemical processes such as fluidized bed coal gasification. The apparatus includes a means for separating the hot process gas from the motor using a secondary lower temperature gas, thereby minimizing the temperature increase of the motor and associated accessories.

  3. The effect of flow recirculation on abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    Taib, Ishkrizat; Amirnordin, Shahrin Hisham; Madon, Rais Hanizam; Mustafa, Norrizal; Osman, Kahar

    2012-06-01

    The presences of flow recirculation at the abdominal aortic aneurysm (AAA) region yield the unpredictable failure of aneurismal wall. The failure of the aneurismal wall is closely related to the hemodynamic factor. Hemodynamic factor such as pressure and velocity distribution play a significance role of aneurysm growth and rupture. By using the computational approach, the influence of hemodynamic factor is investigated using computational fluid dynamic (CFD) method on the virtual AAA model. The virtual 3D AAAs model was reconstructed from Spiral Computed Tomography scan (CT-scan). The blood flow is assumed as being transient, laminar and Newtonian within a rigid section of the vessel. The blood flow also driven by an imposed of pressure gradient in the form of physiological waveform. The pulsating blood flow is also considered in this simulation. The results on pressure distribution and velocity profile are analyzed to interpret the behaviour of flow recirculation. The results show the forming of vortices is seen at the aneurysm bulge. This vortices is form at the aneurysm region then destroyed rapidly by flow recirculation. Flow recirculation is point out much higher at distal end of aneurysm closed to iliac bifurcation. This phenomenon is managed to increase the possibility of aneurysm growth and rupture.

  4. High-Power Picosecond Pulse Recirculation for Inverse Compton Scattering

    NASA Astrophysics Data System (ADS)

    Jovanovic, Igor; Shverdin, Miro; Gibson, David; Brown, Curtis; Gronberg, Jeff

    2008-11-01

    In the next generation of linear colliders, inverse Compton scattering (ICS) of intense laser pulses on relativistic electron bunches will enable a mode of operation based on energetic γe and γγ collisions, with a significant complementary scientific potential. The efficiency of γ-ray generation via ICS is constrained by the Thomson scattering cross section, resulting in typical laser photon-to- γ efficiencies of <10 -9. Furthermore, repetition rates of the state-of-art high-energy short-pulse lasers are poorly matched with those available from electron accelerators. Laser recirculation has been proposed as a method to address those limitations, but has been limited to only small pulse energies and peak powers. We propose and experimentally demonstrate an alternative, non-interferometric method for laser pulse recirculation that is uniquely capable of recirculating short pulses with energies exceeding 1 J [ I. Jovanovic, M. Shverdin, D. Gibson, and C. Brown, Nucl. Instrum. Methods A 578 160 (2007)]. ICS of recirculated Joule-level laser pulses is compatible with the proposed pulse structure for ILC and has a potential to produce unprecedented peak and average γ-ray brightness in the next generation of sources.

  5. An Inexpensive Recirculating Aquaculture System with Multiple Use Capabilities.

    ERIC Educational Resources Information Center

    Scurlock, Gerald Don, Jr.; Cook, S. Bradford; Scurlock, Carrie Ann

    1999-01-01

    Describes the construction of an inexpensive recirculating aquaculture system that can hold up to 46 pounds of fish, invertebrates, and mussels for classroom use. The system is versatile, requires little maintenance, and can be used for both teaching and research purposes. (WRM)

  6. Ozone degradation of alkylbenzene sulfonate in aqueous solutions using a stirred tank reactor with recirculation.

    PubMed

    Jurado-Alameda, Encarnación; Vicaria, José M; Altmajer-Vaz, Deisi; Luzón, Germán; Jiménez-Pérez, José L; Moya-Ramírez, Ignacio

    2012-01-01

    The degradation of linear alkylbenzene sulfonates (LAS) in aqueous solutions by ozone has been investigated. The ozonation process was performed in a stirred tank reactor with recirculation which simulates the clean-in-place process used in many industrial facilities. The gas-liquid mass transfer of ozone in a buffer solution at different temperatures (25-55°C) was also studied in the same device, revealing that ozone decomposition can be considered negligible under the experimental conditions assayed. The effect of the initial LAS concentration, temperature, and ozone concentration on the concentration of homologues and total LAS were analysed as a function of time. Both concentrations diminished with time, this effect being more significant when higher temperatures were assayed. The relative proportion of homologues shows that the homologues of higher chain length are degraded in a greater proportion than are the homologues with shorter chain lengths.

  7. Modular Zero Energy. BrightBuilt Home

    SciTech Connect

    Aldrich, Robb; Butterfield, Karla

    2016-03-01

    With funding from the Building America Program, part of the U.S. Department of Energy Building Technologies Office, the Consortium for Advanced Residential Buildings (CARB) worked with BrightBuilt Home (BBH) to evaluate and optimize building systems. CARB’s work focused on a home built by Black Bros. Builders in Lincolnville, Maine (International Energy Conservation Code Climate Zone 6). As with most BBH projects to date, modular boxes were built by Keiser Homes in Oxford, Maine.

  8. Teaching about the Built Environment. ERIC Digest.

    ERIC Educational Resources Information Center

    Graves, Ginny

    Critical thinking, responsible citizenship, cultural literacy, social relevancy; these concerns of educators in the social studies can be addressed through teaching and learning about the built environment. The tangible structures that humans have created (bridges, houses, factories, farms, monuments) constitute the built environment. Objects in…

  9. Built Environment Education in Art Education.

    ERIC Educational Resources Information Center

    Guilfoil, Joanne K., Ed.; Sandler, Alan R., Ed.

    This anthology brings the study of the built environment, its design, social and cultural functions, and the criticism thereof into focus. Following a preface and introduction, 22 essays are organized in three parts. Part 1 includes: (1) "Landscape Art and the Role of the Natural Environment in Built Environment Education" (Heather…

  10. Digital feedwater and recirculation flow control for GPUN Oyster Creek

    SciTech Connect

    Burjorjee, D. ); Gan, B. )

    1992-01-01

    This paper describes the digital system for feedwater and recirculation control that GPU Nuclear will be installing at Oyster Creek during its next outage - expected circa December 1992. The replacement was motivated by considerations of reliability and obsolescence - the analog equipment was aging and reaching the end of its useful life. The new system uses Atomic Energy of Canada Ltd.'s software platform running on dual, redundant, industrial-grade 386 computers with opto-isolated field input/output (I/O) accessed through a parallel bus. The feedwater controller controls three main feed regulating valves, two low flow regulating valves, and two block valves. The recirculation controller drives the five scoop positioners of the hydraulic couplers. The system also drives contacts that lock up the actuators on detecting an open circuit in their current loops.

  11. Research on leachate recirculation from different types of landfills

    SciTech Connect

    Wang Qi . E-mail: wangqi@craes.org.cn; Matsufuji, Yasushi; Dong Lu; Huang Qifei; Hirano, Fumiaki; Tanaka, Ayako

    2006-07-01

    Landfills can produce a great amount of leachate containing highly concentrated organic matter. This is especially true for the initial leachate from landfilled municipal solid wastes (MSW) that generally has concentrations of COD{sub Cr} and BOD{sub 5} up to 80,000 and 50,000 mg/L, respectively. The leachate could be disposed by means of recirculating technique, which decomposes the organics through the action of proliferating microorganisms and thereby purifies the leachate, and simultaneously accelerates organic decomposition through water saturation control. Data from experimental results indicated that leachate recirculating could reduce the organic concentration considerably, with a maximum reduction rate of COD{sub Cr} over 95%; and, using a semi-aerobic process, NH{sub 3}-N concentration of treated leachate could be under 10 mg/L. In addition, the organic concentration in MSW decreased greatly.

  12. Control of synchrotron radiation effects during recirculation with bunch compression

    SciTech Connect

    Douglas, David; Benson, Stephen; Li, Rui; Roblin, Yves; Tennant, Christopher; Krafft, Geoffrey; Terzic, Balsa; Tsai, Cheng

    2015-05-01

    Studies of beam quality during recirculation have been extended to an arc providing bunch compression with positive momentum compaction. It controls both incoherent and coherent synchrotron radiation (ISR and CSR) using methods including optics balance and generates little microbunching gain. We detail the dynamical basis for the design, discuss the design process, give an example, and provide simulations of ISR and CSR effects. Reference will be made to a complete analysis of microbunching effects.

  13. Post-stenotic Recirculating Flow May Cause Hemodynamic Perforator Infarction

    PubMed Central

    Kim, Bum Joon; Ha, Hojin; Huh, Hyung Kyu; Kim, Guk Bae; Kim, Jong S.; Kim, Namkug; Lee, Sang-Joon; Kang, Dong-Wha; Kwon, Sun U.

    2016-01-01

    Background and Purpose The primary mechanism underlying paramedian pontine infarction (PPI) is atheroma obliterating the perforators. Here, we encountered a patient with PPI in the post-stenotic area of basilar artery (BA) without a plaque, shown by high-resolution magnetic resonance imaging (HR-MRI). We performed an experiment using a 3D-printed BA model and a particle image velocimetry (PIV) to explore the hemodynamic property of the post-stenotic area and the mechanism of PPI. Methods 3D-model of a BA stenosis was reconstructed with silicone compound using a 3D-printer based on the source image of HR-MRI. Working fluid seeded with fluorescence particles was used and the velocity of those particles was measured horizontally and vertically. Furthermore, microtubules were inserted into the posterior aspect of the model to measure the flow rates of perforators (pre-and post-stenotic areas). The flow rates were compared between the microtubules. Results A recirculating flow was observed from the post-stenotic area in both directions forming a spiral shape. The velocity of the flow in these regions of recirculation was about one-tenth that of the flow in other regions. The location of recirculating flow well corresponded with the area with low-signal intensity at the time-of-flight magnetic resonance angiography and the location of PPI. Finally, the flow rate through the microtubule inserted into the post-stenotic area was significantly decreased comparing to others (P<0.001). Conclusions Perforator infarction may be caused by a hemodynamic mechanism altered by stenosis that induces a recirculation flow. 3D-printed modeling and PIV are helpful understanding the hemodynamics of intracranial stenosis. PMID:26687122

  14. Tracking studies in eRHIC energy-recovery recirculator

    SciTech Connect

    Meot, F.; Brooks, S.; Ptitsyn, V.; Trbojevic, D.; Tsoupas, N.

    2015-07-13

    Beam and polarization tracking studies in eRHIC energy recovery electron recirculator are presented, based on a very preliminary design of the FFAG lattice. These simulations provide examples of some of the beam and spin optics aspects of the linear FFAG lattice concept and its application in eRHIC, they provide code benchmarking for synchrotron radiation and spin diffusion in addition, and pave the way towards end-to-end 6-D(phasespace)+3D(spin) tracking simulations.

  15. Improved numerical methods for turbulent viscous recirculating flows

    NASA Technical Reports Server (NTRS)

    Turan, A.

    1985-01-01

    The hybrid-upwind finite difference schemes employed in generally available combustor codes possess excessive numerical diffusion errors which preclude accurate quantative calculations. The present study has as its primary objective the identification and assessment of an improved solution algorithm as well as discretization schemes applicable to analysis of turbulent viscous recirculating flows. The assessment is carried out primarily in two dimensional/axisymetric geometries with a view to identifying an appropriate technique to be incorporated in a three-dimensional code.

  16. Improved numerical methods for turbulent viscous recirculating flows

    NASA Technical Reports Server (NTRS)

    Vandoormaal, J. P.; Turan, A.; Raithby, G. D.

    1986-01-01

    The objective of the present study is to improve both the accuracy and computational efficiency of existing numerical techniques used to predict viscous recirculating flows in combustors. A review of the status of the study is presented along with some illustrative results. The effort to improve the numerical techniques consists of the following technical tasks: (1) selection of numerical techniques to be evaluated; (2) two dimensional evaluation of selected techniques; and (3) three dimensional evaluation of technique(s) recommended in Task 2.

  17. LONGITUDINAL DYNAMICS IN HIGH FREQUENCY FFAG RECIRCULATING ACCELERATORS.

    SciTech Connect

    BERG,J.S.

    2002-04-08

    A recirculating accelerator accelerates the beam by passing through accelerating cavities multiple times. An FFAG recirculating accelerator uses a single arc to connect the linacs together, as opposed to multiple arcs for the different energies. For most scenarios using high-frequency RF, it is impractical to change the phase of the RF on each pass, at least for lower energy accelerators. Ideally, therefore, the WAG arc will be isochronous, so that the particles come back to the same phase (on-crest) on each linac pass. However, it is not possible to make the FFAG arcs isochronous (compared to the RF period) over a large energy range. This paper demonstrates that one can nonetheless make an WAG recirculating accelerator work. Given the arc's path length as a function of energy and the number of turns to accelerate for, one can find the minimum voltage (and corresponding initial conditions) required to accelerate a reference particle to the desired energy. I also briefly examine how the longitudinal acceptance varies with the number of turns that one accelerates.

  18. Cyclone reactor with internal separation and axial recirculation

    DOEpatents

    Becker, F.E.; Smolensky, L.A.

    1988-07-19

    A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture is described. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combustor chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture may be tangentially withdrawn from the outlet end and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture. 10 figs.

  19. Cyclone reactor with internal separation and axial recirculation

    DOEpatents

    Becker, Frederick E.; Smolensky, Leo A.

    1989-01-01

    A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combuston chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture of flue gas and ash may be tangentially withdrawn from the outlet end of the combustor chamber and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture.

  20. Pulsed power requirements for the Sandia recirculating electron beam linac

    SciTech Connect

    Tucker, W.K.; Shope, S.L.; Hasti, D.E.

    1987-01-01

    Compact, high gradient, linear induction accelerators may be achieved by recirculating the electron beam in phase with a repeating accelerating voltage. A two-cavity recirculating accelerator has been designed and operated in a single-pass mode. The prototype accelerator uses a 2.5-MV, 20-kA, 25-ns duration injector and an accelerating cavity that will produce a total accelerating voltage of 5.3 MV for four passes. The design of this machine involved key areas of development in pulsed power, specifically, low-jitter spark gaps and vacuum-liquid interfaces for bipolar electric fields. The extension of this technology to multiple-pulse machines will require advances in liquid dielectric breakdown strength and switch surface flashover, as well as additional improvements in lower inductance switching and vacuum-liquid interface flashover. This paper will discuss the recirculation concept, pulsed-power design parameters, machine scaling relationships that are valid for state-of-the-art and near-term pulsed-power parameters, and summarize the pulsed-power and beam transport experiments.

  1. Modeling of leachate recirculation using vertical wells in bioreactor landfills.

    PubMed

    Feng, Shi-Jin; Cao, Ben-Yi; Zhang, Xu; Xie, Hai-Jian

    2015-06-01

    Leachate recirculation (LR) in municipal solid waste (MSW) landfills operated as bioreactors offers significant economic and environmental benefits. The subsurface application method of vertical wells is one of the most common LR techniques. The objective of this study was to develop a novel two-dimensional model of leachate recirculation using vertical wells. This novel method can describe leachate flow considering the effects of MSW settlement while also accounting separately for leachate flow in saturated and unsaturated zones. In this paper, a settlement model for MSW when considering the effects of compression and biodegradation on the MSW porosity was adopted. A numerical model was proposed using new governing equations for the saturated and unsaturated zones of a landfill. The following design parameters were evaluated by simulating the recirculated leachate volume and the influence zones of waste under steady-state flow conditions: (1) the effect of MSW settlement, (2) the effect of the initial void ratio, (3) the effect of the injected head, (4) the effect of the unit weight, (5) the effect of the biodegradation rate, and (6) the effect of the compression coefficient. The influence zones of LR when considering the effect of MSW settlement are smaller than those when neglecting the effect. The influence zones and LR volume increased with an increase in the injection pressure head and initial void ratio of MSW. The proposed method and the calculation results can provide important insight into the hydrological behavior of bioreactor landfills.

  2. Recirculation of Laser Power in an Atomic Fountain

    NASA Technical Reports Server (NTRS)

    Enzer, Daphna G.; Klipstein, WIlliam M.; Moore, James D.

    2007-01-01

    A new technique for laser-cooling atoms in a cesium atomic fountain frequency standard relies on recirculation of laser light through the atom-collection region of the fountain. The recirculation, accomplished by means of reflections from multiple fixed beam-splitter cubes, is such that each of two laser beams makes three passes. As described below, this recirculation scheme offers several advantages over prior designs, including simplification of the laser system, greater optical power throughput, fewer optical and electrical connections, and simplification of beam power balancing. A typical laser-cooled cesium fountain requires the use of six laser beams arranged as three orthogonal pairs of counter-propagating beams to decelerate the atoms and hold them in a three-dimensional optical trap in vacuum. Typically, these trapping/cooling beams are linearly polarized and are positioned and oriented so that (1) counter-propagating beams in each pair have opposite linear polarizations and (2) three of the six orthogonal beams have the sum of their propagation directions pointing up, while the other three have the sum of their propagation directions pointing down. In a typical prior design, two lasers are used - one to generate the three "up" beams, the other to generate the three "down" beams. For this purpose, the output of each laser is split three ways, then the resulting six beams are delivered to the vacuum system, independently of each other, via optical fibers. The present recirculating design also requires two lasers, but the beams are not split before delivery. Instead, only one "up" beam and one oppositely polarized "down" beam are delivered to the vacuum system, and each of these beams is sent through the collection region three times. The polarization of each beam on each pass through the collection region is set up to yield the same combination of polarization and propagation directions as described above. In comparison with the prior design, the present

  3. Investigation on inlet recirculation characteristics of double suction centrifugal compressor with unsymmetrical inlet

    NASA Astrophysics Data System (ADS)

    Yang, Ce; Wang, Yingjun; Lao, Dazhong; Tong, Ding; Wei, Longyu; Liu, Yixiong

    2016-08-01

    The inlet recirculation characteristics of double suction centrifugal compressor with unsymmetrical inlet structures were studied in numerical method, mainly focused on three issues including the amounts and differences of the inlet recirculation in different working conditions, the circumferential non-uniform distributions of the inlet recirculation, the recirculation velocity distributions of the upstream slot of the rear impeller. The results show that there are some differences between the recirculation of the front impeller and that of the rear impeller in whole working conditions. In design speed, the recirculation flow rate of the rear impeller is larger than that of the front impeller in the large flow range, but in the small flow range, the recirculation flow rate of the rear impeller is smaller than that of the front impeller. In different working conditions, the recirculation velocity distributions of the front and rear impeller are non-uniform along the circumferential direction and their non-uniform extents are quite different. The circumferential non-uniform extent of the recirculation velocity varies with the working conditions change. The circumferential non-uniform extent of the recirculation velocity of front impeller and its distribution are determined by the static pressure distribution of the front impeller, but that of the rear impeller is decided by the coupling effects of the inlet flow distortion of the rear impeller, the circumferential unsymmetrical distribution of the upstream slot and the asymmetric structure of the volute. In the design flow and small flow conditions, the recirculation velocities at different circumferential positions of the mean line of the upstream slot cross-section of the rear impeller are quite different, and the recirculation velocities distribution forms at both sides of the mean line are different. The recirculation velocity distributions in the cross-section of the upstream slot depend on the static pressure

  4. Principles of As-Built Engineering

    SciTech Connect

    Dolin, R.M.; Hefele, J.

    1996-11-01

    As-Built Engineering is a product realization methodology founded on the notion that life-cycle engineering should be based on what is actually produced and not on what is nominally designed. As-Built Engineering is a way of thinking about the production realization process that enables customization in mass production environments. It questions the relevance of nominal based methods of engineering and the role that tolerancing plays in product realization. As-Built Engineering recognizes that there will always be errors associated with manufacturing that cannot be controlled and therefore need to be captured in order to fully characterize each individual product`s unique attributes. One benefit of As-Built Engineering is the ability to provide actual product information to designers and analysts enabling them to verify their assumptions using actual part and assembly data. Another benefit is the ability to optimize new and re-engineered assemblies.

  5. Built Environment Analysis Tool: April 2013

    SciTech Connect

    Porter, C.

    2013-05-01

    This documentation describes the tool development. It was created to evaluate the effects of built environment scenarios on transportation energy and greenhouse gas (GHG) emissions. This documentation also provides guidance on how to apply the tool.

  6. Facility Management's Role in Organizational Sustainability

    ERIC Educational Resources Information Center

    Adams, Gregory K.

    2013-01-01

    Facility managers have questions about sustainability. How do an organization's physical facilities--its built environment--and the management of them, influence the sustainability of the organization or institution as a whole? How important is Facility Management (FM) to the overall sustainability profile of an organization? Facility managers…

  7. The Built Environment Predicts Observed Physical Activity

    PubMed Central

    Kelly, Cheryl; Wilson, Jeffrey S.; Schootman, Mario; Clennin, Morgan; Baker, Elizabeth A.; Miller, Douglas K.

    2014-01-01

    Background: In order to improve our understanding of the relationship between the built environment and physical activity, it is important to identify associations between specific geographic characteristics and physical activity behaviors. Purpose: Examine relationships between observed physical activity behavior and measures of the built environment collected on 291 street segments in Indianapolis and St. Louis. Methods: Street segments were selected using a stratified geographic sampling design to ensure representation of neighborhoods with different land use and socioeconomic characteristics. Characteristics of the built environment on-street segments were audited using two methods: in-person field audits and audits based on interpretation of Google Street View imagery with each method blinded to results from the other. Segments were dichotomized as having a particular characteristic (e.g., sidewalk present or not) based on the two auditing methods separately. Counts of individuals engaged in different forms of physical activity on each segment were assessed using direct observation. Non-parametric statistics were used to compare counts of physically active individuals on each segment with built environment characteristic. Results: Counts of individuals engaged in physical activity were significantly higher on segments with mixed land use or all non-residential land use, and on segments with pedestrian infrastructure (e.g., crosswalks and sidewalks) and public transit. Conclusion: Several micro-level built environment characteristics were associated with physical activity. These data provide support for theories that suggest changing the built environment and related policies may encourage more physical activity. PMID:24904916

  8. Energy balance affected by electrolyte recirculation and operating modes in microbial fuel cells.

    PubMed

    Jacobson, Kyle S; Kelly, Patrick T; He, Zhen

    2015-03-01

    Energy recovery and consumption in a microbial fuel cell (MFC) can be significantly affected by the operating conditions. This study investigated the effects of electrolyte recirculation and operation mode (continuous vs sequence batch reactor) on the energy balance in a tubular MFC. It was found that decreasing the anolyte recirculation also decreased the energy recovery. Because of the open environment of the cathode electrode, the catholyte recirculation consumed 10 to 50 times more energy than the anolyte recirculation, and resulted in negative energy balances despite the reduction of the anolyte recirculation. Reducing the catholyte recirculation to 20% led to a positive energy balance of 0.0288 kWh m(-3). The MFC operated as a sequence batch reactor generated less energy and had a lower energy balance than the one with continuous operation. Those results encourage the further development of MFC technology to achieve neutral or even positive energy output.

  9. Recirculation-aeration: Bibliography for aquaculture. Bibliographies and literature of agriculture (Final)

    SciTech Connect

    Perschbacher, P.W.; Powell, R.V.; Freeman, D.W.; Lorio, W.J.; Hanfman, D.T.

    1993-08-01

    The bibliography includes literature citations through 1992 related to water recirculation and aeration in aquaculture. The focus is on filtration, aeration, and circulation techniques in various aquaculture situations.

  10. Recirculating sand filters for treatment of synthetic dairy parlor washings.

    PubMed

    Healy, M G; Rodgers, M; Mulqueen, J

    2004-01-01

    Land-spreading and spray irrigation are the most widely used practices for the disposal of dairy wastewaters in Ireland but in some cases there can be problems due to contamination of surface and ground water. The use of intermittent sand filtration has been suggested as an alternative treatment process. However, a single pass through a sand filter limits denitrification because of the absence of reducing conditions following nitrification and the lack of an available carbon source. This leads to poor total nitrogen (TN) reduction and an effluent that is high in nitrate nitrogen (NO3-N). This paper follows a previous paper in which two instrumented stratified sand filter columns (0.9 and 0.425 m deep, and both 0.3 m in diameter) were intermittently loaded with synthetic dairy parlor washings at a number of hydraulic loading rates, leading to a TN reduction of 27 to 41%. In the present study, under a chemical oxygen demand (COD) of 23.4 g m(-2) d(-1), the TN was reduced by 83.2% when three-quarters of the sand filter effluent was recirculated through an anoxic zone. This produced an effluent NO3-N concentration of 60 mg L(-1). With recirculation, the improvement in the removal of organic matter and ammonia N (NH4-N) is minimal. Recirculating sand filters appear to offer a mechanically simple and effective method for the removal of nitrogen from dairy parlor effluents and are a significant improvement over a single-pass sand filter.

  11. Built Environment Influences on Healthy Transportation Choices: Bicycling versus Driving

    PubMed Central

    Brauer, Michael; Setton, Eleanor M.; Teschke, Kay

    2010-01-01

    A growing body of evidence links the built environment to physical activity levels, health outcomes, and transportation behaviors. However, little of this research has focused on cycling, a sustainable transportation option with great potential for growth in North America. This study examines associations between decisions to bicycle (versus drive) and the built environment, with explicit consideration of three different spatial zones that may be relevant in travel behavior: trip origins, trip destinations, and along the route between. We analyzed 3,280 utilitarian bicycle and car trips in Metro Vancouver, Canada made by 1,902 adults, including both current and potential cyclists. Objective measures were developed for built environment characteristics related to the physical environment, land use patterns, the road network, and bicycle-specific facilities. Multilevel logistic regression was used to model the likelihood that a trip was made by bicycle, adjusting for trip distance and personal demographics. Separate models were constructed for each spatial zone, and a global model examined the relative influence of the three zones. In total, 31% (1,023 out of 3,280) of trips were made by bicycle. Increased odds of bicycling were associated with less hilliness; higher intersection density; less highways and arterials; presence of bicycle signage, traffic calming, and cyclist-activated traffic lights; more neighborhood commercial, educational, and industrial land uses; greater land use mix; and higher population density. Different factors were important within each spatial zone. Overall, the characteristics of routes were more influential than origin or destination characteristics. These findings indicate that the built environment has a significant influence on healthy travel decisions, and spatial context is important. Future research should explicitly consider relevant spatial zones when investigating the relationship between physical activity and urban form. PMID

  12. Built environment influences on healthy transportation choices: bicycling versus driving.

    PubMed

    Winters, Meghan; Brauer, Michael; Setton, Eleanor M; Teschke, Kay

    2010-12-01

    A growing body of evidence links the built environment to physical activity levels, health outcomes, and transportation behaviors. However, little of this research has focused on cycling, a sustainable transportation option with great potential for growth in North America. This study examines associations between decisions to bicycle (versus drive) and the built environment, with explicit consideration of three different spatial zones that may be relevant in travel behavior: trip origins, trip destinations, and along the route between. We analyzed 3,280 utilitarian bicycle and car trips in Metro Vancouver, Canada made by 1,902 adults, including both current and potential cyclists. Objective measures were developed for built environment characteristics related to the physical environment, land use patterns, the road network, and bicycle-specific facilities. Multilevel logistic regression was used to model the likelihood that a trip was made by bicycle, adjusting for trip distance and personal demographics. Separate models were constructed for each spatial zone, and a global model examined the relative influence of the three zones. In total, 31% (1,023 out of 3,280) of trips were made by bicycle. Increased odds of bicycling were associated with less hilliness; higher intersection density; less highways and arterials; presence of bicycle signage, traffic calming, and cyclist-activated traffic lights; more neighborhood commercial, educational, and industrial land uses; greater land use mix; and higher population density. Different factors were important within each spatial zone. Overall, the characteristics of routes were more influential than origin or destination characteristics. These findings indicate that the built environment has a significant influence on healthy travel decisions, and spatial context is important. Future research should explicitly consider relevant spatial zones when investigating the relationship between physical activity and urban form.

  13. Efficient random subcloning of DNA sheared in a recirculating point-sink flow system.

    PubMed Central

    Oefner, P J; Hunicke-Smith, S P; Chiang, L; Dietrich, F; Mulligan, J; Davis, R W

    1996-01-01

    Based on a high-performance liquid chromatographic pump, we have built a device that allows recirculation of DNA through a 63-microm orifice with ensuing fractionation to a minimum fragment size of approximately 300 base pairs. Residence time of the DNA fragments in the converging flow created by a sudden contraction was found to be sufficiently long to allow extension of the DNA molecules into a highly extended conformation and, hence, breakage to occur at midpoint. In most instances, 30 passages sufficed to obtain a narrow size distribution, with >90% of the fragments lying within a 2-fold size distribution. The shear rate required to achieve breakage was found to be inversely proportional to the 1.0 power of the molecular weight. Compared with a restriction digest, up to 40% of all fragments could be cloned directly, with only marginal improvements in cloning efficiency having been observed upon prior end repair with Klenow, T4 polymerase or T4 polynucleotide kinase. Sequencing revealed a fairly random distribution of the fragments. PMID:8918787

  14. A recirculating hydroponic system for studying peanut (Arachis hypogaea L.)

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Wheeler, R. M.; Stutte, G. W.; Yorio, N. C.; Ruffe, L. M.; Sager, J. C. (Principal Investigator)

    1998-01-01

    Peanut (Arachis hypogaea L.) plants were grown hydroponically, using continuously recirculating nutrient solution. Two culture tray designs were tested; one tray design used only nutrient solution, while the other used a sphagnum-filled pod development compartment just beneath the cover and above the nutrient solution. Both trays were fitted with slotted covers to allow developing gynophores to reach the root zone. Peanut seed yields averaged 350 gm-2 dry mass, regardless of tray design, suggesting that substrate is not required for hydroponic peanut production.

  15. Gun and optics calculations for the Fermilab recirculation experiment

    SciTech Connect

    Kroc, T.

    1997-10-01

    Fermilab is investigating electron cooling to recycle 8 Gev antiprotons recovered from the Tevatron. To do so, it is developing an experiment to recirculate 2 Mev electrons generated by a Pelletron at National Electrostatics Corporation. This paper reports on the optics calculations done in support of that work. We have used the computer codes EGN2 and MacTrace to represent the gun area and acceleration columns respectively. In addition to the results of our simulations, we discuss some of the problems encountered in interfacing the two codes.

  16. Bio-inspired robotic legs drive viscous recirculating flows

    NASA Astrophysics Data System (ADS)

    Takagi, Daisuke; Hayashi, Rintaro

    2015-11-01

    Crustaceans actuate multiple legs in a well-coordinated sequence to generate suitable flow for feeding and swimming. Inspired by tiny crustacean larvae operating at low Reynolds number, we study a scaled-up model in which slender rods oscillate independently in a bath of glycerol. Experiments reveal qualitatively different flow patterns depending on the phase and orientation of actuated rods. The observations are analyzed in the framework of slender-body theory for Stokes flow. This study shows that simple oscillatory motion of multiple legs can produce complex recirculating flows, with potential applications for mixing and pumping.

  17. Lymphopoiesis and lymphocyte recirculation in the sheep fetus

    PubMed Central

    1976-01-01

    The production and the circulation of lymphocytes has been examined in the sheep fetus where neither foreign antigen nor immunoglobulins occur. It was found that as the lymphoid organs increased in size during fetal life, the numbers and the output of lymphocytes in the thoracic duct lymph increased. The recirculating pool of lymphocytes was estimated to be 5.5 +/- 1.5 X 10(8) cells in fetal lambs 95-100 days of age, 5.7 +/- 1.2 X 10(9) cells in fetuses 130-135 days of age, and 1.2 +/0 9.3 X 10(10) cells in fetuses near to term. The rate of addition of lymphocytes to the recirculating pool was 3.2 +/- 1.9 X 10(6) cells/h in fetuses of 100 days and 3.4 +/- 0.9 X 10(7) cells/h in fetuses of 130 days of age. Lymphocytes recirculated from blood to lymph in fetuses; labeled cells injected into the blood stream reappeared in the thoracic duct lymph promptly and reached maximum levels around 12-18 h after they were injected. Labeled lymphocytes were detected subsequently in greatest numbers in the lymph nodes, particularly in the mesenteric lymph nodes and in the interfollicular areas of the Peyer's patches. Chronic drainage of thoracic duct lymph from fetuses in utero for periods of up to 36 days had no obvious effects on the growth or development of the fetus and only minimal effects on the content of lymphocytes in the various lymphoid tissues even though the number of cells in the blood and lymph were reduced to between 20-30% of normal levels. Thymectomy done in fetuses about 2 mo befor cannulation of the thoracic duct reduced the output of cells in the thoracic duct to about 25% of normal levels and caused a significant reduction in the content of lymphocytes in the various lymphoid tissues. Thymectomized fetal lambs subjected to thoracic duct drainage for periods up to 2 wk in utero had a similar complement of lymphocytes in their lymphoid tissues to intact thymectomized fetal lambs. Lymphocytes obtained from the thoracic duct lymph of lambs thymectomized 2 mo

  18. Power plant including an exhaust gas recirculation system for injecting recirculated exhaust gases in the fuel and compressed air of a gas turbine engine

    DOEpatents

    Anand, Ashok Kumar; Nagarjuna Reddy, Thirumala Reddy; Shaffer, Jason Brian; York, William David

    2014-05-13

    A power plant is provided and includes a gas turbine engine having a combustor in which compressed gas and fuel are mixed and combusted, first and second supply lines respectively coupled to the combustor and respectively configured to supply the compressed gas and the fuel to the combustor and an exhaust gas recirculation (EGR) system to re-circulate exhaust gas produced by the gas turbine engine toward the combustor. The EGR system is coupled to the first and second supply lines and configured to combine first and second portions of the re-circulated exhaust gas with the compressed gas and the fuel at the first and second supply lines, respectively.

  19. Knowledge from data in the built environment.

    PubMed

    Starkey, Christopher; Garvin, Chris

    2013-08-01

    Data feedback is changing our relationship to the built environment. Both traditional and new sources of data are developing rapidly, compelled by efforts to optimize the performance of human habitats. However, there are many obstacles to the successful implementation of information-centered environments that continue to hinder widespread adoption. This paper identifies these obstacles and challenges and describes emerging data-rich analytic techniques in infrastructure, buildings, and building portfolios. Further, it speculates on the impact that a robust data sphere may have on the built environment and posits that linkages to other data sets may enable paradigm shifts in sustainability and resiliency.

  20. Built Environment Energy Analysis Tool Overview (Presentation)

    SciTech Connect

    Porter, C.

    2013-04-01

    This presentation provides an overview of the Built Environment Energy Analysis Tool, which is designed to assess impacts of future land use/built environment patterns on transportation-related energy use and greenhouse gas (GHG) emissions. The tool can be used to evaluate a range of population distribution and urban design scenarios for 2030 and 2050. This tool was produced as part of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  1. Combined-cycle plant built in record time

    SciTech Connect

    1995-04-01

    This article reports that this low-cost cogeneration plant meets residential community`s environmental concerns with noise minimization, emissions control, and zero wastewater discharge. Supplying electricity to the local utility and steam to two hosts, the Auburndale cogeneration facility embodies the ``reference plant`` design approach developed by Westinghouse Power Generation (WPG), Orlando, Fla. With this approach customers meet their particular needs by choosing from a standard package of plant equipment and design options. Main goals of the concept are reduced construction time efficient and reliable power generation, minimal operating staff, and low cost. WPG built the plant on a turnkey basis for Auburndale Power Partners Limited Partnership (APP). APP is a partially owned subsidiary of Mission Energy, a California-based international developer and operator of independent-power facilities. The cogeneration facility supplies 150 MW of electric power to Florida Power Corp and exports 120,000 lb/hr of steam to Florida Distillers Co and Coca-Cola Foods.

  2. Simple and Cooperatively Built Wave Motion Demonstrator

    ERIC Educational Resources Information Center

    Cortel, Adolf

    2006-01-01

    Some designs of simple wave demonstration devices have been described in this journal and elsewhere. A new simple model can be built using only dowels, binder clips, and loops of thread. Not only can it be easily assembled, stored, or disassembled, but also all the students in a class can cooperate in its building by connecting successive pieces…

  3. Built Environment Correlates of Walking: A Review

    PubMed Central

    Saelens, Brian E.; Handy, Susan L.

    2010-01-01

    Introduction The past decade has seen a dramatic increase in the empirical investigation into the relations between built environmental and physical activity. To create places that facilitate and encourage walking, practitioners need an understanding of the specific characteristics of the built environment that correlate most strongly with walking. This paper reviews evidence on the built environment correlates with walking. Method Included in this review were 13 reviews published between 2002 and 2006 and 29 original studies published in 2005 and up through May 2006. Results were summarized based on specific characteristics of the built environment and transportation walking versus recreational walking. Results Previous reviews and newer studies document consistent positive relations between walking for transportation and density, distance to non-residential destinations, and land use mix; findings for route/network connectivity, parks and open space, and personal safety are more equivocal. Results regarding recreational walking were less clear. Conclusions More recent evidence supports the conclusions of prior reviews, and new studies address some of the limitations of earlier studies. Although prospective studies are needed, evidence on correlates appears sufficient to support policy changes. PMID:18562973

  4. Schooling Built on the Multiple Intelligences

    ERIC Educational Resources Information Center

    Kunkel, Christine D.

    2009-01-01

    This article features a school built on multiple intelligences. As the first multiple intelligences school in the world, the Key Learning Community shapes its students' days to include significant time in the musical, spatial and bodily-kinesthetic intelligences, as well as the more traditional areas of logical-mathematical and linguistics. In…

  5. Multichannel Analyzer Built from a Microcomputer.

    ERIC Educational Resources Information Center

    Spencer, C. D.; Mueller, P.

    1979-01-01

    Describes a multichannel analyzer built using eight-bit S-100 bus microcomputer hardware. The output modes are an oscilloscope display, print data, and send data to another computer. Discusses the system's hardware, software, costs, and advantages relative to commercial multichannels. (Author/GA)

  6. Interactive method for computation of viscous flow with recirculation

    NASA Technical Reports Server (NTRS)

    Brandeis, J.; Rom, J.

    1981-01-01

    An interactive method is proposed for the solution of two-dimensional, laminar flow fields with identifiable regions of recirculation, such as the shear-layer-driven cavity flow. The method treats the flow field as composed of two regions, with an appropriate mathematical model adopted for each region. The shear layer is computed by the compressible boundary layer equations, and the slowly recirculating flow by the incompressible Navier-Stokes equations. The flow field is solved iteratively by matching the local solutions in the two regions. For this purpose a new matching method utilizing an overlap between the two computational regions is developed, and shown to be most satisfactory. Matching of the two velocity components, as well as the change in velocity with respect to depth is amply accomplished using the present approach, and the stagnation points corresponding to separation and reattachment of the dividing streamline are computed as part of the interactive solution. The interactive method is applied to the test problem of a shear layer driven cavity. The computational results are used to show the validity and applicability of the present approach.

  7. Passive mode control in the recirculating planar magnetron

    SciTech Connect

    Franzi, Matthew; Gilgenbach, Ronald; Lau, Y. Y.; Greening, Geoff; Zhang, Peng; Hoff, Brad

    2013-03-15

    Preliminary experiments of the recirculating planar magnetron microwave source have demonstrated that the device oscillates but is susceptible to intense mode competition due, in part, to poor coupling of RF fields between the two planar oscillators. A novel method of improving the cross-oscillator coupling has been simulated in the periodically slotted mode control cathode (MCC). The MCC, as opposed to a solid conductor, is designed to electromagnetically couple both planar oscillators by allowing for the propagation of RF fields and electrons through resonantly tuned gaps in the cathode. Using the MCC, a 12-cavity anode block with a simulated 1 GHz and 0.26 c phase velocity (where c is the speed of light) was able to achieve in-phase oscillations between the two sides of the device in as little as 30 ns. An analytic study of the modified resonant structure predicts the MCC's ability to direct the RF fields to provide tunable mode separation in the recirculating planar magnetron. The self-consistent solution is presented for both the degenerate even (in phase) and odd (180 Degree-Sign out of phase) modes that exist due to the twofold symmetry of the planar magnetrons.

  8. Continuous hydroponic wheat production using a recirculating system

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Owens, L. P.; Hinkle, C. R.; Prince, R. P.

    1989-01-01

    Continuous crop production, where plants of various ages are growing simultaneously in a single recirculating nutrient solution, is a possible alternative to batch production in a Controlled Ecological Life Support System. A study was conducted at John F. Kennedy Space Center where 8 trays (0.24 sq m per tray) of Triticum aestivum L. Yecora Rojo were grown simultaneously in a growth chamber at 23 C, 65 percent relative humidity, 1000 ppm CO2, continuous light, with a continuous flow, thin film nutrient delivery system. The same modified Hoagland nutrient solution was recirculated through the plant trays from an 80 L reservoir throughout the study. It was maintained by periodic addition of water and nutrients based on chemical analyses of the solution. The study was conducted for 216 days, during which 24 trays of wheat were consecutively planted (one every 9 days), 16 of which were grown to maturity and harvested. The remaining 8 trays were harvested on day 216. Grain yields averaged 520 g m(exp -2), and had an average edible biomass of 32 percent. Consecutive yields were unaffected by nutrient solution age. It was concluded that continual wheat production will work in this system over an extended period of time. Certain micronutrient deficiencies and toxicities posed problems and must be addressed in future continuous production systems.

  9. Self-Recirculating Casing Treatment Concept for Enhanced Compressor Performance

    NASA Technical Reports Server (NTRS)

    Hathaway, Michael D.

    2002-01-01

    A state-of-the-art CFD code (APNASA) was employed in a computationally based investigation of the impact of casing bleed and injection on the stability and performance of a moderate speed fan rotor wherein the stalling mass flow is controlled by tip flow field breakdown. The investigation was guided by observed trends in endwall flow characteristics (e.g., increasing endwall aerodynamic blockage) as stall is approached and based on the hypothesis that application of bleed or injection can mitigate these trends. The "best" bleed and injection configurations were then combined to yield a self-recirculating casing treatment concept. The results of this investigation yielded: 1) identification of the fluid mechanisms which precipitate stall of tip critical blade rows, and 2) an approach to recirculated casing treatment which results in increased compressor stall range with minimal or no loss in efficiency. Subsequent application of this approach to a high speed transonic rotor successfully yielded significant improvements in stall range with no loss in compressor efficiency.

  10. Vortical Structures in Wall-Bounded Turbulent Flow with Recirculation

    NASA Astrophysics Data System (ADS)

    Imran Shah, Syed

    2011-12-01

    Hairpin or horse-shoe vortices are a widely-accepted feature of the wall-bounded flows. These vortical structures have mostly been studied in canonical flows. Relatively few studies have been conducted on the characteristics of the vortical structures in wall-bounded flows with adverse pressure gradient and still fewer on the detached flows with recirculation. In the present contribution, vortices have been educed using a DNS database of incompressible flow over a 2-dimensional surface bump in a converging-diverging channel at a Reynolds number Reτ of 617, based on the friction velocity at inlet. Vortices have been educed from the instantaneous velocity field in streamwise/wall-normal and spanwise/wall-normal planes using the signed swirling strength criterion. Vortex validation is done through a fit of the vortex velocity field to the Oseen vortex model. The effects of a strong adverse pressure gradient and flow reciruclation on the population density and sizes of the streamwise and spanwise-oriented vortices have been studied. It has been found that a strong adverse pressure gradient and flow recirculation leads to the generation of a new near-wall peak of small spanwise prograde vortex population. Furthermore, this peak of vortex density has been found to coincide and hence relate to the outward movement of the peak of streamwise rms velocity fluctuations typical of adverse pressure gradient wall-bounded turbulent flows.

  11. In situ treatment of VOCs by recirculation technologies

    SciTech Connect

    Webb, O.F.; Siegrist, R.L.; Ally, M.R.; Sanford, W.E.; Kearl, P.M.; Zutman, J.L.

    1994-06-01

    Confronted with contaminated land from the world wars and the postwar industrialization period, German researchers and practicing professionals have worked to develop processes for effective environmental restoration. This presentation documents efforts by Oak Ridge National Laboratory (ORNL) researchers to (1) identify collaborators and German technologies exhibiting near-term potential for clean-up of volatile organic contaminated soil and groundwater at Department of Energy sites, (2) critically assess performance, and (3) inform interested agencies. The project was limited to identification and preliminary evaluation and included engineering computations, groundwater flow modeling, and treatment process modeling. Two processes were identified: (1) the vacuum vaporizer well/groundwater recirculation well and (2) the porous pipe/horizontal well (PP/HW). Both technologies induce a recirculation flow field in the aquifer and enable simultaneous down hole treatment of the aquifer and vadose zone. University of Karlsruhe researchers have demonstrated the UVB/GZB technology in shallow aquifers with moderately high saturated thickness and hydraulic conductivities. The PP/HW technology offers potential for VOC treatment in sites with thin aquifers or heterogeneities. This paper describes identified German technologies and includes critical evaluations of well performance, associated treatment processes, operating variables, and aquifer-well interactions.

  12. Design validation and performance of closed loop gas recirculation system

    NASA Astrophysics Data System (ADS)

    Kalmani, S. D.; Joshi, A. V.; Majumder, G.; Mondal, N. K.; Shinde, R. R.

    2016-11-01

    A pilot experimental set up of the India Based Neutrino Observatory's ICAL detector has been operational for the last 4 years at TIFR, Mumbai. Twelve glass RPC detectors of size 2 × 2 m2, with a gas gap of 2 mm are under test in a closed loop gas recirculation system. These RPCs are continuously purged individually, with a gas mixture of R134a (C2H2F4), isobutane (iC4H10) and sulphur hexafluoride (SF6) at a steady rate of 360 ml/h to maintain about one volume change a day. To economize gas mixture consumption and to reduce the effluents from being released into the atmosphere, a closed loop system has been designed, fabricated and installed at TIFR. The pressure and flow rate in the loop is controlled by mass flow controllers and pressure transmitters. The performance and integrity of RPCs in the pilot experimental set up is being monitored to assess the effect of periodic fluctuation and transients in atmospheric pressure and temperature, room pressure variation, flow pulsations, uniformity of gas distribution and power failures. The capability of closed loop gas recirculation system to respond to these changes is also studied. The conclusions from the above experiment are presented. The validations of the first design considerations and subsequent modifications have provided improved guidelines for the future design of the engineering module gas system.

  13. Designing and Testing of Self-Cleaning Recirculating Zebrafish Tanks.

    PubMed

    Nema, Shubham; Bhargava, Yogesh

    2016-08-01

    Maintenance of large number of zebrafish in captive conditions is a daunting task. This can be eased by the use of recirculating racks with self-cleaning zebrafish tanks. Commercially available systems are costly, and compatibility of intercompany products has never been investigated. Although various cost-effective designs and methods of construction of custom-made recirculating zebrafish racks are available in literature, the design of self-cleaning zebrafish tanks is still not available. In this study, we report the design and method of construction of the self-cleaning unit, which can be fitted in any zebrafish tank. We validated the design by investigating sediment cleaning process in rectangular and cylindrical tank geometries using time lapse imaging. Our results suggest that for both tank geometries, the tanks fitted with self-cleaning unit provided superior sediment cleaning than the tanks fitted with overflow-drain unit. Although the self-cleaning unit could clean the sediment completely from both geometries over prolonged period, the cleaning of sediments was faster in the cylindrical tank than the rectangular tank. In conclusion, cost and efforts of zebrafish maintenance could be significantly reduced through the installation of our self-cleaning unit in any custom-made zebrafish tank.

  14. Design and installation of a high Reynolds number recirculating water tunnel

    NASA Astrophysics Data System (ADS)

    Daniel, Libin

    The High-Reynolds Number Fluid Mechanics Laboratory has recently been established at Oklahoma State University (OSU). The three primary components of the laboratory are 1) a recirculating water tunnel, 2) a multiphase pipe flow facility, and 3) a multi-scale flow visualization system. This thesis focuses on the design and fabrication of the water tunnel, which will be used for high-Reynolds number turbulent boundary layer research. Two main design criteria for the water tunnel were to achieve a momentum thickness based Reynolds number in excess of 104 and to have high optical access to the flow surfaces in the test section. This is being achieved with a 1 m. long test section and a maximum flow speed of 10 m/s. This Reynolds number was targeted to bridge the gap between typical university water tunnels (103) and the world's largest water tunnel facilities (105). The water tunnel is powered by a 150 hp motor and a 4500 gpm capacity centrifugal pump. The water tunnel is designed for a maximum operating pressure of 40 psi. This will make the facility a low cost option to perform high-Reynolds number aerodynamic and hydrodynamic tests. Improved flow imaging capability is a major advantage to liquid based fluid facilities because of the increased density for seeding and reduced field-of-view for equivalent Reynolds number. The laboratory's state-of-the-art flow visualization system can be used for time-resolved and phase averaged stereo- particle-image-velocimetry (sPIV), laser-induced-fluorescence, and high-speed imaging. Design provisions are also made to allow a multi-phase loop to share the pump and motor configuration of this water tunnel facility. The major design decisions that went into the design of the water tunnel facility are discussed. The design considerations that were taken into account for the test section, flow conditioning sections and the entire flow loop are discussed in greater detail. The final configuration and the technical drawings of the water

  15. Unit process engineering for water quality control and biosecurity in marine water recirculating systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High-intensity systems that treat and recirculate water must maintain a culture environment that can sustain near optimum fish health and growth at the design carrying capacity. Water recirculating systems that use centralized treatment systems can benefit from the economies of scale to decrease th...

  16. Inactivation of bacteria using ultraviolet irradiation in a recirculating salmonid culture system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this research was to determine the ultraviolet (UV) irradiation dosages required to inactivate bacteria in a commercial-scale recirculating salmonid culture system. Research was conducted in the commercial-scale recirculating system used for Arctic char growout at the Conservation ...

  17. Facility Focus: Science Facilities.

    ERIC Educational Resources Information Center

    College Planning & Management, 2001

    2001-01-01

    Discusses design and architectural features of two new science facilities at the Florida Institute of Technology in Melbourne, Florida, and a new graduate research tower the University of Wisconsin at Madison. Notes the important convenience associated with interior windows in these facilities, which allow researchers, faculty, and students to see…

  18. Physics design and scaling of recirculating induction accelerators: from benchtop prototypes to drivers

    SciTech Connect

    Barnard, J.J.; Cable, M.D.; Callahan, D.A.

    1996-02-06

    Recirculating induction accelerators (recirculators) have been investigated as possible drivers for inertial fusion energy production because of their potential cost advantage over linear induction accelerators. Point designs were obtained and many of the critical physics and technology issues that would need to be addressed were detailed. A collaboration involving Lawrence Livermore National Laboratory and Lawrence Berkeley National Laboratory researchers is now developing a small prototype recirculator in order to demonstrate an understanding of nearly all of the critical beam dynamics issues that have been raised. We review the design equations for recirculators and demonstrate how, by keeping crucial dimensionless quantities constant, a small prototype recirculator was designed which will simulate the essential beam physics of a driver. We further show how important physical quantities such as the sensitivity to errors of optical elements (in both field strength and placement), insertion/extraction, vacuum requirements, and emittance growth, scale from small-prototype to driver-size accelerator.

  19. Performance model of a recirculating stack nickel hydrogen cell

    NASA Technical Reports Server (NTRS)

    Zimmerman, Albert H.

    1994-01-01

    A theoretical model of the nickel hydrogen battery cell has been utilized to describe the chemical and physical changes during charge and overcharge in a recirculating stack nickel hydrogen cell. In particular, the movement of gas and electrolyte have been examined as a function of the amount of electrolyte put into the cell stack during cell activation, and as a function of flooding in regions of the gas screen in this cell design. Additionally, a two-dimensional variation on this model has been utilized to describe the effects of non-uniform loading in the nickel-electrode on the movement of gas and electrolyte within the recirculating stack nickel hydrogen cell. The type of nonuniform loading that has been examined here is that associated with higher than average loading near the surface of the sintered nickel electrode, a condition present to some degree in many nickel electrodes made by electrochemical impregnation methods. The effects of high surface loading were examined primarily under conditions of overcharge, since the movement of gas and electrolyte in the overcharging condition was typically where the greatest effects of non-uniform loading were found. The results indicate that significant changes in the capillary forces between cell components occur as the percentage of free volume in the stack filled by electrolyte becomes very high. These changes create large gradients in gas-filled space and oxygen concentrations near the boundary between the separator and the hydrogen electrode when the electrolyte fill is much greater than about 95 percent of the stack free volume. At lower electrolyte fill levels, these gaseous and electrolyte gradients become less extreme, and shift through the separator towards the nickel electrode. Similarly, flooding of areas in the gas screen cause higher concentrations of oxygen gas to approach the platinum/hydrogen electrode that is opposite the back side of the nickel electrode. These results illustrate the need for

  20. Built-Environment Wind Turbine Roadmap

    SciTech Connect

    Smith, J.; Forsyth, T.; Sinclair, K.; Oteri, F.

    2012-11-01

    Although only a small contributor to total electricity production needs, built-environment wind turbines (BWTs) nonetheless have the potential to influence the public's consideration of renewable energy, and wind energy in particular. Higher population concentrations in urban environments offer greater opportunities for project visibility and an opportunity to acquaint large numbers of people to the advantages of wind projects on a larger scale. However, turbine failures will be equally visible and could have a negative effect on public perception of wind technology. This roadmap provides a framework for achieving the vision set forth by the attendees of the Built-Environment Wind Turbine Workshop on August 11 - 12, 2010, at the U.S. Department of Energy's National Renewable Energy Laboratory. The BWT roadmap outlines the stakeholder actions that could be taken to overcome the barriers identified. The actions are categorized as near-term (0 - 3 years), medium-term (4 - 7 years), and both near- and medium-term (requiring immediate to medium-term effort). To accomplish these actions, a strategic approach was developed that identifies two focus areas: understanding the built-environment wind resource and developing testing and design standards. The authors summarize the expertise and resources required in these areas.

  1. Use of fluorescence spectroscopy to control ozone dosage in recirculating aquaculture systems.

    PubMed

    Spiliotopoulou, Aikaterini; Martin, Richard; Pedersen, Lars-Flemming; Andersen, Henrik R

    2017-03-15

    The aim of this study was to investigate the potential of fluorescence spectroscopy to be used as an ozone dosage determination tool in recirculating aquaculture systems (RASs), by studying the relationship between fluorescence intensities and dissolved organic matter (DOM) degradation by ozone, in order to optimise ozonation treatment. Water samples from six different Danish facilities (two rearing units from a commercial trout RAS, a commercial eel RAS, a pilot RAS and two marine water aquariums) were treated with different O3 dosages (1.0-20.0 mg/L ozone) in bench-scale experiments, following which fluorescence intensity degradation was eventually determined. Ozonation kinetic experiments showed that RAS water contains fluorescent organic matter, which is easily oxidised upon ozonation in relatively low concentrations (0-5 mg O3/L). Fluorescence spectroscopy has a high level of sensitivity and selectivity in relation to associated fluorophores, and it is able to determine accurately the ozone demand of each system. The findings can potentially be used to design offline or online sensors based on the reduction by ozone of natural fluorescent-dissolved organic matter in RAS. The suggested indirect determination of ozone delivered into water can potentially contribute to a safer and more adequate ozone-based treatment to improve water quality.

  2. Recirculating accelerator driver for a high-power free-electron laser: A design overview

    SciTech Connect

    Bohn, C.L.

    1997-06-01

    Jefferson Lab is building a free-electron laser (FEL) to produce continuous-wave (cw), kW-level light at 3-6 {mu}m wavelength. A superconducting linac will drive the laser, generating a 5 mA average current, 42 MeV energy electron beam. A transport lattice will recirculate the beam back to the linac for deceleration and conversion of about 75% of its power into rf power. Bunch charge will range up to 135 pC, and bunch lengths will range down to 1 ps in parts of the transport lattice. Accordingly, space charge in the injector and coherent synchrotron radiation in magnetic bends come into play. The machine will thus enable studying these phenomena as a precursor to designing compact accelerators of high-brightness beams. The FEL is scheduled to be installed in its own facility by 1 October 1997. Given the short schedule, the machine design is conservative, based on modifications of the CEBAF cryomodule and MIT-Bates transport lattice. This paper surveys the machine design.

  3. 2. EAST ELEVATION OF IPA FACTORY; TWOSTORY SECTION BUILT IN ...

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

    2. EAST ELEVATION OF IPA FACTORY; TWO-STORY SECTION BUILT IN 1892 AND PARTIALLY DESTROYED PARAPET SECTION BUILT CA. 1948. BRICK CHIMNEY ALSO BUILT CA. 1948. - Illinois Pure Aluminum Company, 109 Holmes Street, Lemont, Cook County, IL

  4. One Bedroom Units: Floor Plan, South Elevation (As Built), North ...

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

    One Bedroom Units: Floor Plan, South Elevation (As Built), North Elevation (As Built), Section A-A (As Built), Section AA (Existing) - Aluminum City Terrace, East Hill Drive, New Kensington, Westmoreland County, PA

  5. TRACG Simulation of Drywell Gas Recirculation System in ESBWR

    SciTech Connect

    Cheung, Yee K.; Rao, Atambir S.

    2002-07-01

    This paper presents the results of a parametric study on the mitigating effects of the Drywell Gas Recirculation System (DGRS) in ESBWR during postulated LOCA and severe accidents. The post-accident containment pressure depends on the sum of the partial pressure from non-condensable gases and partial steam pressure inside the wet-well airspace. Results of parametric studies show that, with the activation of DGRS: (1) The containment pressure continues to reduce due to the redistribution of non-condensable gases from the wet-well back to the drywell; (2) The DGRS can be designed in a 'portable' fashion; (3) The Current ESBWR meets the design requirement with significant margin using only passive safety systems, and the margin increases considerably with the activation of DGRS. (authors)

  6. Dynamics of microorganism populations in recirculating nutrient solutions

    NASA Technical Reports Server (NTRS)

    Strayer, R. F.

    1994-01-01

    This overview covers the basic microbial ecology of recirculating hydroponic solutions. Examples from NASA and Soviet Controlled Ecological Life Support Systems (CELSS) tests and the commercial hydroponic industry will be used. The sources of microorganisms in nutrient solutions include air, water, seeds, plant containers and plumbing, biological vectors, and personnel. Microbial fates include growth, death, and emigration. Important microbial habitats within nutrient delivery systems are root surfaces, hardware surfaces (biofilms), and solution suspension. Numbers of bacteria on root surfaces usually exceed those from the other habitats by several orders of magnitude. Gram negative bacteria dominate the microflora with fungal counts usually much lower. Trends typically show a decrease in counts with increasing time unless stressed plants increase root exudates. Important microbial activities include carbon mineralization and nitrogen transformations. Important detrimental interactions include competition with plants, and human and plant pathogenesis.

  7. Dynamics of microorganism populations in recirculating nutrient solutions

    NASA Technical Reports Server (NTRS)

    Strayer, R. F.

    1994-01-01

    This overview covers the basic microbial ecology of recirculating hydroponic solutions. Examples from NASA and Soviet CELSS tests and the commercial hydroponic industry will be used. The sources of microorganisms in nutrient solutions include air, water, seeds, plant containers and plumbing, biological vectors, and personnel. Microbial fates include growth, death, and emigration. Important microbial habitats within nutrient delivery systems are root surfaces, hardware surfaces (biofilms), and solution suspension. Numbers of bacteria on root surfaces usually exceed those from the other habitats by several orders of magnitude. Gram negative bacteria dominate the microflora with fungal counts usually much lower. Trends typically show a decrease in counts with increasing time unless stressed plants increase root exudates. Important microbial activities include carbon mineralization and nitrogen transformations. Important detrimental interactions include competition with plants, and human and plant pathogenesis.

  8. Successful water reuse in open recirculating cooling systems

    SciTech Connect

    Vaska, M.; Lee, B.

    1994-12-31

    Water reuse in open recirculating cooling water systems is becoming increasingly prevalent in industry. Reuse can incorporate a number of varied approaches with the primary goal being water conservation. Market forces driving this trend include scarcity of fresh water makeup sources and higher costs associated with pretreatment of natural waters. Utilization of reuse water for cooling tower makeup has especially detrimental effects on corrosion and deposit rates. Additionally, once the reuse water is cycled and treated with inhibitors, dispersants and microbiocides, acceptability for discharge to a public waterway can be a concern. The task for water treatment suppliers is to guide industry in the feasibility and procedures for successfully achieving these goals. This paper focuses particularly on reuse of municipal wastewater for cooling tower makeup and explores techniques which have been found especially effective. Case histories are described where these concepts have been successfully applied in practice.

  9. Experiments With Recirculating Target for F-18 Production

    NASA Astrophysics Data System (ADS)

    Kiselev, M. Y.

    2003-08-01

    Approximately 10 ml of O-18 water was loaded in an apparatus containing a 5 ml storage vessel, pump, silver target attached to a cyclotron, filter, backpressure regulator, conductivity meter, several valves and ion exchange cartridges. The water was continuously pumped through the target during proton bombardment at a rate 5 ml/min. Continuous irradiation with beam current ranging from 10 to 50 uA was conducted while pressure, temperature and conductivity were continuously monitored. The results indicate that recirculating of the target water can increase production of F-18 in relation to consumed O-18 water material. It can also increase productivity by eliminating idle periods for re-filling the target. A backpressure regulator can precisely control target pressure. This method also allows for continuous monitoring of the target material temperature, pressure, conductivity and accumulated radioactivity. Results of these observations provide important information about target performance and physical processes taking place inside the target.

  10. Capture of CO2 From Recirculating Flue Gas Boilers

    SciTech Connect

    Ochs, Thomas L.

    2003-01-01

    The possible need for an economical method for the separation of CO2 from flue gas adds a new set of challenges to power plant design, construction, operation, and maintenance. Many of the new requirements of CO2 separation are similar in nature to those addressed by the mature chemical engineering processes used in petroleum refining and industrial chemical production. Chemical engineering processes are regularly used to separate heterogeneous vapors in processes such as the fractionation of hydrocarbons or the separation of the components of air. This paper addresses the application of chemical engineering processes to the mixtures of gases and vapors found in the flue gas of recirculating boilers. Adaptation of these techniques can lead to a reduction in the energy required to capture CO2.

  11. Computation of recirculating compressible flow in axisymmetric geometries

    SciTech Connect

    Isaac, K.M.; Nejad, A.S.

    1985-01-01

    A computational study of compressible, turbulent, recirculating flow in axisymmetric geometries is reported in this paper. The SIMPLE algorithm was used in the differencing scheme and the k-epsilon model for turbulence was used for turbulence closure. Special attention was given to the specification of the boundary conditions. The study revealed the significant influence of the boundary conditions on the solution. The eddy length scale at the inlet to the solution domain was the most uncertain parameter in the specification of the boundary conditions. The predictions were compared with the recent data based on laser velocimetry. The two are seen to be in good agreement. The present study underscores the need to have a more reliable means of specifying the inlet boundary conditions for the k-epsilon turbulence model.

  12. Dynamics of microorganism populations in recirculating nutrient solutions

    NASA Astrophysics Data System (ADS)

    Strayer, R. F.

    1994-11-01

    This overview covers the basic microbial ecology of recirculating hydroponic solutions. Examples from NASA and Soviet CELSS tests and the commercial hydroponic industry will be used. The sources of microorganisms in nutrient solutions include air, water, seeds, plant containers and plumbing, biological vectors, and personnel. Microbial fates include growth, death, and emigration. Important microbial habitats within nutrient delivery systems are root surfaces, hardware surfaces (biofilms), and solution suspension. Numbers of bacteria on root surfaces usually exceed those from the other habitats by several orders of magnitude. Gram negative bacteria dominate the microflora with fungal counts usually much lower. Trends typically show a decrease in counts with increasing time unless stressed plants increase root exudates. Important microbial activities include carbon mineralization and nitrogen transformations. Important detrimental interactions include competition with plants, and human and plant pathogenesis.

  13. Microbial diversity of biological filters in recirculating aquaculture systems.

    PubMed

    Schreier, Harold J; Mirzoyan, Natella; Saito, Keiko

    2010-06-01

    Development of environmentally sustainable farming of marine and freshwater species using recirculating aquaculture systems (RASs) requires a complete understanding of the biological component involved in wastewater treatment. This component integrates biofilters composed of microbial communities whose structure, dynamics, and activities are responsible for system success. Engineering highly efficient, environmentally sound, disease-free, and economically viable systems necessitates a thorough knowledge of microbial processes involved in all facets of RAS biofilters and has only recently been the focus of comprehensive studies. These studies have included the application of molecular tools to characterize community diversity and have identified key processes useful for improving system performance. In this paper we summarize the current understanding of the microbial diversity and physiology of RAS biofilters and discuss directions for future studies.

  14. Recycling crop residues for use in recirculating hydroponic crop production

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Garland, J. L.; Sager, J. C.

    1996-01-01

    As part of bioregenerative life support feasibility testing by NASA, crop residues are being used to resupply elemental nutrients to recirculating hydroponic crop production systems. Methods for recovering nutrients from crop residues have evolved from water soaking (leaching) to rapid aerobic bioreactor processing. Leaching residues recovered the majority of elements but it also recovered significant amounts of soluble organics. The high organic content of leachates was detrimental to plant growth. Aerobic bioreactor processing reduced the organic content ten-fold, which reduced or eliminated phytotoxic effects. Wheat and potato production studies were successful using effluents from reactors having with 8- to 1-day retention times. Aerobic bioreactor effluents supplied at least half of the crops elemental mass needs in these studies. Descriptions of leachate and effluent mineral content, biomass productivity, microbial activity, and nutrient budgets for potato and wheat are presented.

  15. Fixed Field Alternating Gradient recirculator for heavy ion fusion

    SciTech Connect

    Paul, A.C.; Neil, V.K.

    1991-03-01

    A heavy ion fusion driver is considered in which a beam is passed repeatedly through a LIA (linear induction accelerator) by recirculating with two spiral sector FFAG (Fixed Field Alternating Gradient) 180 degree bends. The driver consists of three such rings: a 10--100 MeV low energy ring (LER), a 100--1000 MeV medium energy ring (MER), and a 1--10 GeV high energy ring (HER). Using a scaling field of 14 kG and taking the length of the straight sections to equal the path length in the bends, the circumference of the three rings would be 187, 590, and 1890 meters. Four matching sections in each of the three rings provide the interface between the two straight sections accommodating the LIA and the FFAG bends. These matching sections consist of dipoles which provide a dispersion free match between the linear induction accelerator and the energy dependent equilibrium orbits of the FFAG ring. The advantage in the use of the spiral sector FFAG over other recirculator concepts is that the fields are time invariant. This removes the problems associated with time dependent field penetration into the vacuum chamber and the large amount of energy which must be expended to change the magnetic field on the small time scale associated with the required pulse repetition frequency. The disadvantage, as we show in this work is the relatively weak alternating gradient focusing. The FFAG will not accommodate the level of beam current possible in a separate function lattice of bending magnets and quadrupoles.

  16. Traffic and proliferative responses of recirculating lymphocytes in fetal calves.

    PubMed Central

    Hein, W R; Shelton, J N; Simpson-Morgan, M W; Morris, B

    1988-01-01

    The thoracic duct or efferent prescapular duct was cannulated in four fetal calves aged 121-259 days post-conception. The duration of lymph flow ranged from 2 to 20 days and the mean flow rates sustained over these collection periods varied from 5.4 to 48.8 ml/hr. Lymphocyte output ranged from 4.4 x 10(6) cells/hr in thoracic duct lymph from a 121-day fetus to 3.9 x 10(8) cells/hr in efferent prescapular lymph from a 259-day fetus. The circulating lymphocyte pool in fetal calves of about 120 and 190 days gestational age was calculated to contain, respectively, 4 x 10(8) cells and 2 x 10(10) cells. The proportion of lymphocytes bearing surface immunoglobulin detected in fetal lymph ranged from 2.1% to 8.7%. Recirculating lymphocytes from fetal calves produced strong proliferative responses when stimulated by T-cell mitogens but responded poorly to B-cell mitogens. Fetal lymphocytes also responded to stimulation by allogeneic cells and stimulated other cells to proliferate during mixed lymphocyte culture. When stimulated with Con A, fetal lymphocytes secreted IL-2 to a degree that was indistinguishable from the secretory behaviour of lymphocytes from adult animals. The results presented in this paper show that chronic lymphatic fistulae can be established successfully in fetal calves to give access to recirculating lymphocytes. This provides a new experimental approach for studying the development of the bovine immune system. PMID:2971606

  17. Use of Produced Water in Recirculated Cooling Systems at Power Generating Facilities

    SciTech Connect

    C. McGowin; M. DiFilippo; L. Weintraub

    2006-06-30

    Tree ring studies indicate that, for the greater part of the last three decades, New Mexico has been relatively 'wet' compared to the long-term historical norm. However, during the last several years, New Mexico has experienced a severe drought. Some researchers are predicting a return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters to supplement current fresh water supplies for power plant operation and cooling and other uses. The U.S. Department of Energy's National Energy Technology Laboratory sponsored three related assessments of water supplies in the San Juan Basin area of the four-corner intersection of Utah, Colorado, Arizona, and New Mexico. These were (1) an assessment of using water produced with oil and gas as a supplemental supply for the San Juan Generating Station (SJGS); (2) a field evaluation of the wet-surface air cooling (WSAC) system at SJGS; and (3) the development of a ZeroNet systems analysis module and an application of the Watershed Risk Management Framework (WARMF) to evaluate a range of water shortage management plans. The study of the possible use of produced water at SJGS showed that produce water must be treated to justify its use in any reasonable quantity at SJGS. The study identified produced water volume and quality, the infrastructure needed to deliver it to SJGS, treatment requirements, and delivery and treatment economics. A number of produced water treatment alternatives that use off-the-shelf technology were evaluated along with the equipment needed for water treatment at SJGS. Wet surface air-cooling (WSAC) technology was tested at the San Juan Generating Station (SJGS) to determine its capacity to cool power plant circulating water using degraded water. WSAC is a commercial cooling technology and has been used for many years to cool and/or condense process fluids. The purpose of the pilot test was to determine if WSAC technology could cool process water at cycles of concentration considered highly scale forming for mechanical draft cooling towers. At the completion of testing, there was no visible scale on the heat transfer surfaces and cooling was sustained throughout the test period. The application of the WARMF decision framework to the San Juan Basis showed that drought and increased temperature impact water availability for all sectors (agriculture, energy, municipal, industry) and lead to critical shortages. WARMF-ZeroNet, as part of the integrated ZeroNet decision support system, offers stakeholders an integrated approach to long-term water management that balances competing needs of existing water users and economic growth under the constraints of limited supply and potential climate change.

  18. Vortex dynamics and scalar transport in the wake of a bluff body driven through a steady recirculating flow

    NASA Astrophysics Data System (ADS)

    Poussou, Stephane B.; Plesniak, Michael W.

    2012-09-01

    The air ventilation system in wide-body aircraft cabins provides passengers with a healthy breathing environment. In recent years, the increase in global air traffic has amplified contamination risks by airborne flu-like diseases and terrorist threats involving the onboard release of noxious materials. In particular, passengers moving through a ventilated cabin may transport infectious pathogens in their wake. This paper presents an experimental investigation of the wake produced by a bluff body driven through a steady recirculating flow. Data were obtained in a water facility using particle image velocimetry and planar laser induced fluorescence. Ventilation attenuated the downward convection of counter-rotating vortices produced near the free-end corners of the body and decoupled the downwash mechanism from forward entrainment, creating stagnant contaminant regions.

  19. Investigation of groundwater recirculation for the removal of RDX from the Pantex Plant perched aquifer

    SciTech Connect

    Woods, A.L.; Barnes, D.L.; Boles, K.M.; Charbeneau, R.J.; Black, S.; Rainwater, K.

    1998-07-01

    The Pantex Plant near Amarillo, Texas, is a US Department of Energy (DOE) facility that has been in operation since 1942. Past and present operations at Pantex include the creation of chemical high explosives components for nuclear weapons and assembly and disassembly of nuclear weapons. The Pantex Plant is underlain by the Ogallala aquifer, which in this area, consists of the main water-bearing unit and a perched water zone. These are separated by a fine-grained zone of low permeability. Multiple contaminant plumes containing high explosive (HE) compounds have been detected in the perched aquifer beneath the plant. The occurrence of these contaminants is the result of past waste disposal practices at the facility. RDX is an HE compound, which has been detected in the groundwater of the perched aquifer at significant concentrations. A pilot-scale, dual-phase extraction treatment system has been installed at one location at the plant, east of Zone 12, to test the effectiveness of such a system on the removal of these contaminants from the subsurface. A tracer test using a conservative tracer, bromide (Br), was conducted at the treatment site in 1996. In addition to the bromide, RDX and water elevations in the aquifer were monitored. Using data from the tracer test and other relevant data from the investigations at Pantex, flow and contaminant transport in the perched aquifer were simulated with groundwater models. The flow was modeled using MODFLOW and the transport of contaminants in the aqueous phase was modeled using MT3D. Modeling the perched aquifer had been conducted to characterize the flow in the perched aquifer; estimate RDX retardation in the perched aquifer; and evaluate the use of groundwater re-circulation to enhance the extraction of RDX from the perched aquifer.

  20. External built residential environment characteristics that affect mental health of adults.

    PubMed

    Ochodo, Charles; Ndetei, D M; Moturi, W N; Otieno, J O

    2014-10-01

    External built residential environment characteristics include aspects of building design such as types of walls, doors and windows, green spaces, density of houses per unit area, and waste disposal facilities. Neighborhoods that are characterized by poor quality external built environment can contribute to psychosocial stress and increase the likelihood of mental health disorders. This study investigated the relationship between characteristics of external built residential environment and mental health disorders in selected residences of Nakuru Municipality, Kenya. External built residential environment characteristics were investigated for 544 residents living in different residential areas that were categorized by their socioeconomic status. Medically validated interview schedules were used to determine mental health of residents in the respective neighborhoods. The relationship between characteristics of the external built residential environment and mental health of residents was determined by multivariable logistic regression analyses and chi-square tests. The results show that walling materials used on buildings, density of dwelling units, state of street lighting, types of doors, states of roofs, and states of windows are some built external residential environment characteristics that affect mental health of adult males and females. Urban residential areas that are characterized by poor quality external built environment substantially expose the population to daily stressors and inconveniences that increase the likelihood of developing mental health disorders.

  1. Sulfur recirculation for increased electricity production in Waste-to-Energy plants.

    PubMed

    Andersson, Sven; Blomqvist, Evalena W; Bäfver, Linda; Jones, Frida; Davidsson, Kent; Froitzheim, Jan; Karlsson, Martin; Larsson, Erik; Liske, Jesper

    2014-01-01

    Sulfur recirculation is a new technology for reducing boiler corrosion and dioxin formation. It was demonstrated in full-scale tests at a Waste to Energy plant in Göteborg (Sweden) during nearly two months of operation. Sulfur was recirculated as sulfuric acid from the flue gas cleaning back to the boiler, thus creating a sulfur loop. The new technology was evaluated by extensive measurement campaigns during operation under normal conditions (reference case) and operation with sulfur recirculation. The chlorine content of both fly ash and boiler ash decreased and the sulfur content increased during the sulfur recirculation tests. The deposit growth and the particle concentration decreased with sulfur recirculation and the dioxin concentration (I-TEQ) of the flue gas was reduced by approximately 25%. Sulfuric acid dew point measurements showed that the sulfuric acid dosage did not lead to elevated SO3 concentrations, which may otherwise induce low temperature corrosion. In the sulfur recirculation corrosion probe exposures, the corrosion rate decreased for all tested materials (16Mo3, Sanicro 28 and Inconel 625) and material temperatures (450 °C and 525 °C) compared to the reference exposure. The corrosion rates were reduced by 60-90%. Sulfur recirculation prevented the formation of transition metal chlorides at the metal/oxide interface, formation of chromate and reduced the presence of zinc in the corrosion products. Furthermore, measured corrosion rates at 525 °C with sulfur recirculation in operation were similar or lower compared to those measured at 450 °C material temperature in reference conditions, which corresponds to normal operation at normal steam temperatures. This implies that sulfur recirculation allows for higher steam data and electricity production without increasing corrosion.

  2. Effects of effluent recirculation in vertical-flow constructed wetland on treatment efficiency of livestock wastewater.

    PubMed

    Lian-sheng, He; Hong-liang, Liu; Bei-dou, Xi; Ying-bo, Zhu

    2006-01-01

    Enhancing the treatment efficiency of livestock wastewater by effluent recirculation is investigated in a pilot-scale vertical-flow constructed wetland. The wetland system is composed of downflow and upflow stages, on which narrow-leaf Phragmites communis and common reed Phragmites typhia are planted, respectively; each stage has a dimension of 4 m(2) (2 m x 2 m). Wastewater from the facultative pond is fed into the system intermittently at a flow rate of 0.4 m(3)/d. Recirculation rates of 0, 25%, 50%0, 100% and 150% are adopted to evaluate the effect of the recirculation rate on pollutants removal. This shows that with effluent recirculation the average removal efficiencies of NH4-N, BOD5 and SS obviously increase to 61.7%, 81.3%, and 77.1%, respectively, in comparison with the values of 35.6%o, 50.2%, and 49.3% without effluent recirculation. But the improvement of TP removal is slight, only from 42.3% to 48.9%. The variations of NH4-N, DO and oxidation-reduction potential (ORP) of inflow and outflow reveal that the adoption of effluent recirculation is beneficial to the formation of oxide environment in wetland. The exponential relationships with excellent correlation coefficients (R(2) > 0.93) are found between the removal rates of NH4-N and BOD5 and the recirculation rates. With recirculation the pH value of the outflow decreases as the alkalinity is consumed by the gradually enhanced nitrification process. When recirculation rate is kept constant at 100%, the ambient temperature appears to affect NH4-N removal, but does not have significant influence on BOD5 removal.

  3. Cell buffer with built-in test

    NASA Technical Reports Server (NTRS)

    Ott, William E. (Inventor)

    2004-01-01

    A cell buffer with built-in testing mechanism is provided. The cell buffer provides the ability to measure voltage provided by a power cell. The testing mechanism provides the ability to test whether the cell buffer is functioning properly and thus providing an accurate voltage measurement. The testing mechanism includes a test signal-provider to provide a test signal to the cell buffer. During normal operation, the test signal is disabled and the cell buffer operates normally. During testing, the test signal is enabled and changes the output of the cell buffer in a defined way. The change in the cell buffer output can then be monitored to determine if the cell buffer is functioning correctly. Specifically, if the voltage output of the cell buffer changes in a way that corresponds to the provided test signal, then the functioning of the cell buffer is confirmed. If the voltage output of the cell buffer does not change correctly, then the cell buffer is known not to be operating correctly. Thus, the built in testing mechanism provides the ability to quickly and accurately determine if the cell buffer is operating correctly. Furthermore, the testing mechanism provides this functionality without requiring excessive device size and complexity.

  4. Modular Zero Energy. BrightBuilt Home

    SciTech Connect

    Aldrich, Robb; Butterfield, Karla

    2016-03-01

    Kaplan Thompson Architects (KTA) has specialized in sustainable, energy-efficient buildings, and they have designed several custom, zero-energy homes in New England. These zero-energy projects have generally been high-end, custom homes with budgets that could accommodate advanced energy systems. In an attempt to make zero energy homes more affordable and accessible to a larger demographic, KTA explored modular construction as way to provide high-quality homes at lower costs. In the mid-2013, KTA formalized this concept when they launched BrightBuilt Home (BBH). The BBH mission is to offer a line of architect-designed, high-performance homes that are priced to offer substantial savings off the lifetime cost of a typical home and can be delivered in less time. For the past two years, CARB has worked with BBH and Keiser Homes (the primary modular manufacturer for BBH) to discuss challenges related to wall systems, HVAC, and quality control. In Spring of 2014, CARB and BBH began looking in detail on a home to be built in Lincolnville, ME by Black Bros. Builders. This report details the solution package specified for this modular plan and the challenges that arose during the project.

  5. Hydraulic design of a re-circulating water cooling system of a combined cycle power plant in Thailand

    SciTech Connect

    Sarkar, C.K.; Pandit, D.R.; Kwon, S.G.

    1998-12-31

    The paper describes the hydraulic design and hydraulic transient analysis of the re-circulating water cooling system of the combined cyclo Sipco power cogeneration plant in Thailand. The power plant of 450 MW total capacity is proposed to be built in two stages. Stage one will produce 300 MW of power and will consist of two gas turbine generators (GTG) and one steam turbine generator (STG). Stage two will produce 150 MW of power and will consist of one GTG and one STG. The cooling system will consist of one GTG and one STG. The cooling system will consist of cooling towers, a combined collecting basin and pump intake sump, pumps and motors, and separate conveyance systems and condensers for the generator units in the two stages. In a re-circulating water cooling system, cold water is pumped from the pump intake sump to the condensers through the conveyance system and hot water from the condensers is carried through the returning pipeline system to the cooling towers, whence the water after cooling is drained into the sump at the base of the towers. Total cooling water requirement for the system in stage one is estimated to be 112,000 gallons per minute (GPM), and that in stage two, 56,000 GPM. The sump is designed using the computer program HEC-2, developed by the US Army Corps of Engineers (COE) and the pump intake basin, following the recommendations of the Hydraulic Institute. The pumps were sized by computing the head loss in the system, and, the steady state and transient performances (during pump start-up and shut-down procedures and due to possible power or mechanical failure of one or all pumps) of the system were analyzed by mathematically modeling the system using the computer program WHAMO (Water Hammer nd Mass Oscillations), also developed by the COE.

  6. Breadboard Facility

    NASA Technical Reports Server (NTRS)

    1977-01-01

    In the sixties, Chrysler was NASA's prime contractor for the Saturn I and IB test launch vehicles. The company installed and operated at Huntsville what was known as the Saturn I/IB Development Breadboard Facility. "Breadboard," means an array of electrical and electronic equipment for performing a variety of development and test functions. This work gave Chrysler a broad capability in computerized testing to assure quality control in development of solid-state electronic systems. Today that division is manufacturing many products not destined for NASA, most of them being associated with the company's automotive line. A major project is production and quality-control testing of the "lean-burn" engine, one that has a built-in Computer to control emission timing, and allow the engine to run on a leaner mixture of fuel and air. Other environment-related products include vehicle emission analyzers. The newest of the line is an accurate, portable solid state instrument for testing auto exhaust gases. The exhaust analyzers, now being produced for company dealers and for service

  7. The Large Built Water Clock Of Amphiaraeion.

    NASA Astrophysics Data System (ADS)

    Theodossiou, E.; Katsiotis, M.; Manimanis, V. N.; Mantarakis, P.

    A very well preserved ancient water clock was discovered during excavations at the Amphiaraeion, in Oropos, Greece. The Amphiaraeion, a famous religious and oracle center of the deified healer Amphiaraus, was active from the pre-classic period until the replacement of the ancient religion by Christianity in the 5th Century A.D.. The foretelling was supposedly done through dreams sent by the god to the believers sleeping in a special gallery. In these dreams the god suggesting to them the therapy for their illness or the solution to their problems. The patients, then threw coins into a spring of the sanctuary. In such a place, the measurement of time was a necessity. Therefore, time was kept with both a conical sundial and a water clock in the form of a fountain. According to archeologists, the large built structure that measured the time for the sanctuary dates from the 4th Century B.C.

  8. A Student-Built Scanning Tunneling Microscope

    NASA Astrophysics Data System (ADS)

    Ekkens, Tom

    2015-12-01

    Many introductory and nanotechnology textbooks discuss the operation of various microscopes including atomic force (AFM), scanning tunneling (STM), and scanning electron microscopes (SEM). In a nanotechnology laboratory class, students frequently utilize microscopes to obtain data without a thought about the detailed operation of the tool itself. I wanted to give my students a deeper appreciation for the physics by having them build a simple scanning tunneling microscope. Initially, 15 hours of an upper-division laboratory class were devoted to building and operating the STM. As the build process was refined, the time commitment for this project has shrunk to nine hours. Using the method described in this paper, the project is now simple enough that it can be built and operated by students in the introductory class.

  9. Photocatalytic oxide films in the built environment

    NASA Astrophysics Data System (ADS)

    Österlund, Lars; Topalian, Zareh

    2014-11-01

    The possibility to increase human comfort in buildings is a powerful driving force for the introduction of new technology. Among other things our sense of comfort depends on air quality, temperature, lighting level, and the possibility of having visual contact between indoors and outdoors. Indeed there is an intimate connection between energy, comfort, and health issues in the built environment, leading to a need for intelligent building materials and green architecture. Photocatalytic materials can be applied as coatings, filters, and be embedded in building materials to provide self-cleaning, antibacterial, air cleaning, deodorizing, and water cleaning functions utilizing either solar light or artificial illumination sources - either already present in buildings, or by purposefully designed luminaries. Huge improvements in indoor comfort can thus be made, and also alleviate negative health effects associated with buildings, such as the sick-house syndrome. At the same time huge cost savings can be made by reducing maintenance costs. Photocatalytic oxides can be chemically modified by changing their acid-base surface properties, which can be used to overcome deactivation problems commonly encountered for TiO2 in air cleaning applications. In addition, the wetting properties of oxides can be tailored by surface chemical modifications and thus be made e.g. oleophobic and water repellent. Here we show results of surface acid modified TiO2 coatings on various substrates by means of photo-fixation of surface sulfate species by a method invented in our group. In particular, we show that such surface treatments of photocatalytic concrete made by mixing TiO2 nanoparticles in reactive concrete powders result in concrete surfaces with beneficial self-cleaning properties. We propose that such approaches are feasible for a number of applications in the built environment, including glass, tiles, sheet metals, plastics, etc.

  10. High-Power Laser Pulse Recirculation for Inverse Compton Scattering-Produced Gamma-Rays

    SciTech Connect

    Jovanovic, I; Shverdin, M; Gibson, D; Brown, C

    2007-04-17

    Inverse Compton scattering of high-power laser pulses on relativistic electron bunches represents an attractive method for high-brightness, quasi-monoenergetic {gamma}-ray production. The efficiency of {gamma}-ray generation via inverse Compton scattering is severely constrained by the small Thomson scattering cross section. Furthermore, repetition rates of high-energy short-pulse lasers are poorly matched with those available from electron accelerators, resulting in low repetition rates for generated {gamma}-rays. Laser recirculation has been proposed as a method to address those limitations, but has been limited to only small pulse energies and peak powers. Here we propose and experimentally demonstrate an alternative method for laser pulse recirculation that is uniquely capable of recirculating short pulses with energies exceeding 1 J. Inverse Compton scattering of recirculated Joule-level laser pulses has a potential to produce unprecedented peak and average {gamma}-ray brightness in the next generation of sources.

  11. Efficiency of an AMTEC recirculating test cell, experiments and projections

    SciTech Connect

    Underwood, M.L.; O`Connor, D.; Williams, R.M.; Jeffries-Nakamura, B.; Ryan, M.A.

    1992-05-01

    The alkali metal thermal to electric converter (AMTEC) is an electrochemical device for the direct conversion of heat to electrical energy with efficiencies potentially near Carnot. The future usefulness of AMTEC for space power conversion depends on the efficiency of the devices. Systems studies have projected from 15% to 35% thermal to electric conversion efficiencies, and one experiment has demonstrated 19% efficiency for a short period of time. Recent experiments in a recirculating test cell (RTC) have demonstrated sustained conversion efficiencies as high as 10.2% early in cell life and 9.7% after maturity. Extensive thermal and electrochemical analysis of the cell during several experiments demonstrated that the efficiency could be improved in two ways. First, the electrode performance could be improved. The electrode for these tests operated at about one third the power density of state of the art electrodes. The low power density was caused by a combination of high series resistance and high mass flow resistance. Reducing these resistances could improve the efficiency to greater than 10%. Second, the cell thermal performance could be improved. Efficiencies greater than 14% could be realized through reducing the radiative thermal loss. Further improvements to the efficiency range predicted by systems studies can be accomplished through the development and use of an advanced condenser with improved reflectivity, close to that of a smooth sodium film, and the series connecting of individual cells to further reduce thermal losses.

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

    PubMed Central

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

    2015-01-01

    The current research examines the possibility of using recirculation filters from aircraft to document the nature of air-quality incidents on aircraft. These filters are highly effective at collecting solid and liquid particulates. Identification of engine oil contaminants arriving through the bleed air system on the filter was chosen as the initial focus. A two-step study was undertaken. First, a compressor/bleed air simulator was developed to simulate an engine oil leak, and samples were analyzed with gas chromatograph-mass spectrometry. These samples provided a concrete link between tricresyl phosphates and a homologous series of synthetic pentaerythritol esters from oil and contaminants found on the sample paper. The second step was to test 184 used aircraft filters with the same gas chromatograph-mass spectrometry system; of that total, 107 were standard filters, and 77 were nonstandard. Four of the standard filters had both markers for oil, with the homologous series synthetic pentaerythritol esters being the less common marker. It was also found that 90% of the filters had some detectable level of tricresyl phosphates. Of the 77 nonstandard filters, 30 had both markers for oil, a significantly higher percent than the standard filters. PMID:25641977

  13. AMTEC recirculating test cell component testing and operation

    NASA Technical Reports Server (NTRS)

    Underwood, M. L.; Sievers, R. K.; O'Connor, D.; Williams, R. M.; Jeffries-Nakamura, B.; Bankston, C. P.

    1989-01-01

    Alkali metal thermoelectric converter operation in a recirculating test cell (RTC), which requires a small electromagnetic pump (EM) and a high-temperature beta-double-prime alumina-solid-electrolyte (BASE)-to-metal seal, is discussed. The design of a pump and an active metal braze seal and the initial operation of a cell using these components are described. The pump delivered 0.25 cu cm/min against a 28-psia head. A braze seal system was selected after shear strength tests of Ta or Nb brazed to BASE by a variety of fillers including TiCuNi, TiNi, and TiNiCr. The TiCuNi filler was chosen for environment cell testing and showed no failure or observable degradation after short-term tests up to 1055 K. The pump and the Nb/TiCuNi/BASE seal were used in a test that demonstrated all the operational functions of the RTC for the first time. An increase in the radiation reduction factor at constant input power was observed, indicating that the condenser was being wet by sodium resulting in an increased reflectivity.

  14. In situ treatment of VOCs by recirculation technologies

    SciTech Connect

    Siegrist, R.L.; Webb, O.F.; Ally, M.R.; Sanford, W.E.; Kearl, P.M.; Zutman, J.L.

    1993-06-01

    The project described herein was conducted by Oak Ridge National Laboratory (ORNL) to identify processes and technologies developed in Germany that appeared to have near-term potential for enhancing the cleanup of volatile organic compound (VOC) contaminated soil and groundwater at DOE sites. Members of the ORNL research team identified and evaluated selected German technologies developed at or in association with the University of Karlsruhe (UoK) for in situ treatment of VOC contaminated soils and groundwater. Project activities included contacts with researchers within three departments of the UoK (i.e., Applied Geology, Hydromechanics, and Soil and Foundation Engineering) during fall 1991 and subsequent visits to UoK and private industry collaborators during February 1992. Subsequent analyses consisted of engineering computations, groundwater flow modeling, and treatment process modeling. As a result of these project efforts, two processes were identified as having near-term potential for DOE: (1) the vacuum vaporizer well/groundwater recirculation well and (2) the porous pipe/horizontal well. This document was prepared to summarize the methods and results of the assessment activities completed during the initial year of the project. The project is still ongoing, so not all facets of the effort are completely described in this document. Recommendations for laboratory and field experiments are provided.

  15. Subsets of blood, spleen and recirculating lymphocytes in man.

    PubMed Central

    Reinecke, G; Pabst, R

    1983-01-01

    Lymphocyte subpopulations were characterized in human blood and spleens. In addition the spleens were perfused by a closed extracorporeal perfusion system under almost physiological conditions. Lymphocytes released from the spleen during perfusion were taken to be representative of recirculating lymphocytes. B lymphocytes were classified by their surface immunoglobulin, T lymphocytes and T lymphocyte subsets by cytochemistry, sheep red blood cell rosette formation and in some experiments by monoclonal antibodies. In the blood 71 +/- 4.3% of the lymphocytes were rosette forming cells and 23.3 +/- 3.8% B lymphocytes. In the spleen 49.8 +/- 3.6% were T and 53.3 +/- 2.1% were B lymphocytes. In three spleens the mean number of OKT3+ lymphocytes were 27.6 +/- 7.0% OKT4+ 8.6 +/- 1.4% and OKT8+ 13.7 +/- 2.2%. The ratio of T helper to T suppressor lymphocytes was 0.67 for the spleen and 1.7 for the blood. The lymphocytes released from the perfused spleen showed a similar distribution pattern of surface markers to that of the splenic subpopulations. Images Fig. 1 PMID:6225579

  16. Efficiency of an AMTEC recirculating test cell, experiments and projections

    NASA Technical Reports Server (NTRS)

    Underwood, M. L.; O'Connor, D.; Williams, R. M.; Jeffries-Nakamura, B.; Ryan, M. A.

    1992-01-01

    The alkali metal thermal to electric converter (AMTEC) is an electrochemical device for the direct conversion of heat to electrical energy with efficiencies potentially near Carnot. The future usefulness of AMTEC for space power conversion depends on the efficiency of the devices. Systems studies have projected from 15 to 35 percent thermal to electric conversion efficiencies, and one experiment has demonstrated 19 percent efficiency for a short period of time. Recent experiments in a recirculating test cell (RTC) have demonstrated sustained conversion efficiencies as high as 10.2 percent early in cell life and 9.7 percent after maturity. Extensive thermal and electrochemical analysis of the cell during several experiments demonstrated that the efficiency could be improved in two ways. First, the electrode performance could be improved. The electrode for these tests operated at about one third the power density of state of the art electrodes. The low power density was caused by a combination of high series resistance and high mass flow resistance. Reducing these resistances could improve the efficiency to greater than 10 percent. Second, the cell thermal performance could be improved. Efficiencies greater than 14 percent could be realized through reducing the radiative thermal loss. Further improvements to the efficiency range predicted by systems studies can be accomplished through the development and use of an advanced condenser with improved reflectivity, close to that of a smooth sodium film, and the series connecting of individual cells to further reduce thermal losses.

  17. Effects of Test Cell Recirculation on High-Bypass Turbofan Engines during Simulated Altitude Tests

    DTIC Science & Technology

    1986-08-01

    methods used to describe and correct for test cell recirculation have led to this investigation, which is in line with the objectives previously stated...between pressure profiles on the cell wall and those on the model surfaces, which is in line with previous observations. Removal of the diffuser...AEDC-TR-85-55 , , . ’ . . . .L Effects of Test Cell Recirculation on High-Bypass Turbofan Engines During Simulated Altitude Tests OCT 0 9

  18. Quench performance of Fermilab/General Dynamics built full length SSC collider dipole magnets

    SciTech Connect

    Strait, J.; Orris, D.; Mazur, P.O.; Bleadon, M.; Bossert, R.; Carson, J.; Delchamps, S.W.; Gourlay, S.; Hanft, R.; Koska, W.; Kuchnir, M.; Lamm, M.J.; Ozelis, J.; Wake, M. ); Devred, A.; DiMarco, J.; Kuzminski, J.; Nah, W.; Ogitsu, T.; Puglisi, M.; Tompkins, J.C.; Yu, Y.; Zhao, Y.; Zheng, H. )

    1992-04-01

    In this paper we present results of quench testing of full length SSC dipole magnets at Fermilab. The data are from the first six of a series of thirteen 15 m long, 50 mm aperture SSC dipole magnets which are being built and tested at Fermilab. These magnets were designed jointly by Fermilab, Brookhaven Laboratory, Lawrence Berkeley Laboratory and the SSC laboratory. Among the major goals for this series of magnets are to transfer magnet production technology to the lead vendor for the Collider Dipole Magnet, the General Dynamics Corporation, and to demonstrate industrial production by the vendor. The first magnet in the series, DCA311, was built by Fermilab technicians to establish assembly procedures. The second magnet, DCA312, was the ''technology transfer magnet'' and was built jointly by Fermilab and General Dynamics technicians. The next seven, DCA313- 319 are being built by General Dynamics personnel using Fermilab facilities and procedures. However, Fermilab personnel still operate the major tooling, provide the welders, perform assembly of items that would not be part of production magnets (e.g. voltage taps), and oversee the QA program. Five of these 7 GD-built magnets will be used in the Accelerator Systems String Test (ASST) to be carried out in Dallas later this year. The last four magnets, DCA320-323, are being built by Fermilab alone.

  19. Anolyte recirculation effects in buffered and unbuffered single-chamber air-cathode microbial fuel cells.

    PubMed

    Zhang, Liang; Zhu, Xun; Kashima, Hiroyuki; Li, Jun; Ye, Ding-ding; Liao, Qiang; Regan, John M

    2015-03-01

    Two identical microbial fuel cells (MFCs) with a floating air-cathode were operated under either buffered (MFC-B) or bufferless (MFC-BL) conditions to investigate anolyte recirculation effects on enhancing proton transfer. With an external resistance of 50 Ω and recirculation rate of 1.0 ml/min, MFC-BL had a 27% lower voltage (9.7% lower maximal power density) but a 64% higher Coulombic efficiency (CE) than MFC-B. MFC-B had a decreased voltage output, batch time, and CE with increasing recirculation rate resulting from more oxygen transfer into the anode. However, increasing the recirculation rate within a low range significantly enhanced proton transfer in MFC-BL, resulting in a higher voltage output, a longer batch time, and a higher CE. A further increase in recirculation rate decreased the batch time and CE of MFC-BL due to excess oxygen transfer into anode outweighing the proton-transfer benefits. The unbuffered MFC had an optimal recirculation rate of 0.35 ml/min.

  20. Nitrogen oxides emissions from the MILD combustion with the conditions of recirculation gas.

    PubMed

    Park, Min; Shim, Sung Hoon; Jeong, Sang Hyun; Oh, Kwang-Joong; Lee, Sang-Sup

    2017-04-01

    The nitrogen oxides (NOx) reduction technology by combustion modification which has economic benefits as a method of controlling NOx emitted in the combustion process, has recently been receiving a lot of attention. Especially, the moderate or intense low oxygen dilution (MILD) combustion which applied high temperature flue gas recirculation has been confirmed for its effectiveness with regard to solid fuel as well. MILD combustion is affected by the flue gas recirculation ratio and the composition of recirculation gas, so its NOx reduction efficiency is determined by them. In order to investigate the influence of factors which determine the reduction efficiency of NOx in MILD coal combustion, this study changed the flow rate and concentration of nitrogen (N2), carbon dioxide (CO2) and steam (H2O) which simulate the recirculation gas during the MILD coal combustion using our lab-scale drop tube furnace and performed the combustion experiment. As a result, its influence by the composition of recirculation gas was insignificant and it was shown that flue gas recirculation ratio influences the change of NOx concentration greatly.

  1. Atmospheric stagnation, recirculation and ventilation potential of several sites in Argentina

    NASA Astrophysics Data System (ADS)

    Venegas, L. E.; Mazzeo, N. A.

    Conditions for stagnation, recirculation and ventilation potential of the atmosphere were studied in five argentine cities: Resistencia, Córdoba, Buenos Aires, Mar del Plata and Comodoro Rivadavia, located in different regions of the country. Wind run and recirculation factors were calculated for a 24-h transport time using 2 years of hourly surface measurements of wind speed and direction. The largest stagnation frequency (45% of the time) was observed in Resistencia, located in the northeastern part of the country, in an area where winds are weak. The least frequency of stagnations (2%) was observed in Comodoro Rivadavia, in the southern region of the country, a region dominated by strong westerly winds. Comodoro Rivadavia and Córdoba registered the largest frequency of recirculations. Comodoro Rivadavia exposed to sea-land breezes and Córdoba, located on a complex terrain area and exposed to local circulations, experienced recirculation events during 10% of the time. Good atmospheric ventilation occurs when a high value of wind run and a low value of the recirculation factor are observed and it can be associated with the atmosphere's capacity to replace polluted air with clean air. Ventilation events occurred 58% of the time at Comodoro Rivadavia, 52% at Mar del Plata, 40% at Buenos Aires, 35% at Córdoba and 18% at Resistencia. In general, stagnation was more frequently observed during autumn and winter, recirculation during spring and summer and good ventilation conditions occurred during spring.

  2. National Built Environment Health Impact Assessment Model ...

    EPA Pesticide Factsheets

    Behavioral (activity, diet, social interaction) and exposure (air pollution, traffic injury, and noise) related health impacts of land use and transportation investment decisions are becoming better understood and quantified. Research has shown relationships between density, mix, street connectivity, access to parks, shops, transit, presence of sidewalks and bikeways, and healthy food with physical activity, obesity, cardiovascular disease, type II diabetes, and some mental health outcomes. This session demonstrates successful integration of health impact assessment into multiple scenario planning tool platforms. Detailed evidence on chronic disease and related costs associated with contrasting land use and transportation investments are built into a general-purpose module that can be accessed by multiple platforms. Funders, researchers, and end users of the tool will present a detailed description of the key elements of the approach, how it has been applied, and how will evolve. A critical focus will be placed on equity and social justice inherent within the assessment of health disparities that will be featured in the session. Health impacts of community design have significant cost benefit implications. Recent research is now extending relationships between community design features and chronic disease to health care costs. This session will demonstrate the recent application of this evidence on health impacts to the newly adopted Los Angeles Regional Transpo

  3. The Built Environment Is a Microbial Wasteland

    PubMed Central

    2016-01-01

    ABSTRACT Humanity’s transition from the outdoor environment to the built environment (BE) has reduced our exposure to microbial diversity. The relative importance of factors that contribute to the composition of human-dominated BE microbial communities remains largely unknown. In their article in this issue, Chase and colleagues (J. Chase, J. Fouquier, M. Zare, D. L. Sonderegger, R. Knight, S. T. Kelley, J. Siegel, and J. G. Caporaso, mSystems 1(2):e00022-16, 2016, http://dx.doi.org/10.1128/mSystems.00022-16) present an office building study in which they controlled for environmental factors, geography, surface material, sampling location, and human interaction type. They found that surface location and geography were the strongest factors contributing to microbial community structure, while surface material had little effect. Even in the absence of direct human interaction, BE surfaces were composed of 25 to 30% human skin-associated taxa. The authors demonstrate how technical variation across sequencing runs is a major issue, especially in BE work, where the biomass is often low and the potential for PCR contaminants is high. Overall, the authors conclude that BE surfaces are desert-like environments where microbes passively accumulate. PMID:27832216

  4. A scalable neuristor built with Mott memristors

    NASA Astrophysics Data System (ADS)

    Pickett, Matthew D.; Medeiros-Ribeiro, Gilberto; Williams, R. Stanley

    2013-02-01

    The Hodgkin-Huxley model for action potential generation in biological axons is central for understanding the computational capability of the nervous system and emulating its functionality. Owing to the historical success of silicon complementary metal-oxide-semiconductors, spike-based computing is primarily confined to software simulations and specialized analogue metal-oxide-semiconductor field-effect transistor circuits. However, there is interest in constructing physical systems that emulate biological functionality more directly, with the goal of improving efficiency and scale. The neuristor was proposed as an electronic device with properties similar to the Hodgkin-Huxley axon, but previous implementations were not scalable. Here we demonstrate a neuristor built using two nanoscale Mott memristors, dynamical devices that exhibit transient memory and negative differential resistance arising from an insulating-to-conducting phase transition driven by Joule heating. This neuristor exhibits the important neural functions of all-or-nothing spiking with signal gain and diverse periodic spiking, using materials and structures that are amenable to extremely high-density integration with or without silicon transistors.

  5. Endolithic phototrophs in built and natural stone.

    PubMed

    Gaylarde, Christine C; Gaylarde, Peter M; Neilan, Brett A

    2012-08-01

    Lichens, algae and cyanobacteria have been detected growing endolithically in natural rock and in stone buildings in various countries of Australasia, Europe and Latin America. Previously these organisms had mainly been described in natural carbonaceous rocks in aquatic environments, with some reports in siliceous rocks, principally from extremophilic regions. Using various culture and microscopy methods, we have detected endoliths in siliceous stone, both natural and cut, in humid temperate and subtropical climates. Such endolithic growth leads to degradation of the stone structure, not only by mechanical means, but also by metabolites liberated by the cells. Using in vitro culture, transmission, optical and fluorescence microscopy, and confocal laser scanning microscopy, both coccoid and filamentous cyanobacteria and algae, including Cyanidiales, have been identified growing endolithically in the facades of historic buildings built from limestone, sandstone, granite, basalt and soapstone, as well as in some natural rocks. Numerically, the most abundant are small, single-celled, colonial cyanobacteria. These small phototrophs are difficult to detect by standard microscope techniques and some of these species have not been previously reported within stone.

  6. Development and design of a fluidized bed/upflow sand filter configuration for use in recirculating aquaculture systems

    SciTech Connect

    Burden, D.G.

    1988-01-01

    A fluidized bed/upflow sand filter configuration, was developed and designed for utilization in recirculating aquaculture system, specifically the soft-shell crab and soft-shell crawfish industries. These filters were selected and designed because of their ability to withstand clogging and still maintain high levels of water quality for aquaculture production. The effectiveness of sand grain size was used to evaluate fluidized bed filter performance with filter loadings ranging from 16 to 1285 pounds of crawfish per cubic foot of filter sand. A coarse sand grain size was recommended as a filter media because of it's ability to shear excessive biofilm growth from the and, thus prohibiting clogging from occurring within the filter bed. The fluidized bed/upflow sand filter combination was evaluated in terms of nitrification and oxygen consumption when used with a recirculating crab shedding system. The filter combination's carrying capacity (700 crabs per cubic foot of sand media) exceeded that observed with the submerged rock filter by more than 20 times and was largely explained by the filter's solids removal ability which significantly reduced the filter's oxygen loading rate (OLR). Nitrification rates with the filter combination were extremely high as total ammonia and nitrite levels remained below 1.0 mg-N/l. Verification of a volumetric loading criteria (150 pounds per cubic foot) for this filter combination was further established with performance data obtained from a commercial soft-shell crawfish facility. Water quality monitoring results indicated that the filters maintained total ammonia and nitrite levels below 1.0 mg-N/l under typical operating conditions. Shock loading, pH control, and over-feeding, rather than filter capacity, dominated water quality fluctuations, thereby indicating that the loading criteria was sufficient for commercial operation.

  7. Rayleigh Scattering for Measuring Flow in a Nozzle Testing Facility

    NASA Technical Reports Server (NTRS)

    Gomez, Carlos R.; Panda, Jayanta

    2006-01-01

    A molecular Rayleigh-scattering-based air-density measurement system was built in a large nozzle-and-engine-component test facility for surveying supersonic plumes from jet-engine exhaust. A molecular Rayleigh-scattering-based air-density measurement system was built in a large nozzle-and-enginecomponent test facility for surveying supersonic plumes from jet-engine exhaust

  8. Next Generation Pressurized Oxy-Coal Combustion: High Efficiency and No Flue Gas Recirculation

    SciTech Connect

    Rue, David

    2013-09-30

    The Gas Technology Institute (GTI) has developed a pressurized oxy-coal fired molten bed boiler (MBB) concept, in which coal and oxygen are fired directly into a bed of molten coal slag through burners located on the bottom of the boiler and fired upward. Circulation of heat by the molten slag eliminates the need for a flue gas recirculation loop and provides excellent heat transfer to steam tubes in the boiler walls. Advantages of the MBB technology over other boilers include higher efficiency (from eliminating flue gas recirculation), a smaller and less expensive boiler, modular design leading to direct scalability, decreased fines carryover and handling costs, smaller exhaust duct size, and smaller emissions control equipment sizes. The objective of this project was to conduct techno-economic analyses and an engineering design of the MBB project and to support this work with thermodynamic analyses and oxy-coal burner testing. Techno-economic analyses of GTI’s pressurized oxy-coal fired MBB technology found that the overall plant with compressed CO2 has an efficiency of 31.6%. This is a significant increase over calculated 29.2% efficiency of first generation oxy-coal plants. Cost of electricity (COE) for the pressurized MBB supercritical steam power plant with CO2 capture and compression was calculated to be 134% of the COE for an air-coal supercritical steam power plant with no CO2 capture. This compares positively with a calculated COE for first generation oxy-coal supercritical steam power plants with CO2 capture and compression of 164%. The COE for the MBB power plant is found to meet the U.S. Department of Energy (DOE) target of 135%, before any plant optimization. The MBB power plant was also determined to be simpler than other oxy-coal power plants with a 17% lower capital cost. No other known combustion technology can produce higher efficiencies or lower COE when CO2 capture and compression are included. A thermodynamic enthalpy and exergy analysis

  9. Facility Microgrids

    SciTech Connect

    Ye, Z.; Walling, R.; Miller, N.; Du, P.; Nelson, K.

    2005-05-01

    Microgrids are receiving a considerable interest from the power industry, partly because their business and technical structure shows promise as a means of taking full advantage of distributed generation. This report investigates three issues associated with facility microgrids: (1) Multiple-distributed generation facility microgrids' unintentional islanding protection, (2) Facility microgrids' response to bulk grid disturbances, and (3) Facility microgrids' intentional islanding.

  10. Closed recirculating system for shrimp-mollusk polyculture

    NASA Astrophysics Data System (ADS)

    Wu, Xiongfei; Zhao, Zhidong; Li, Deshang; Chang, Kangmei; Tong, Zhuanshang; Si, Liegang; Xu, Kaichong; Ge, Bailin

    2005-12-01

    This paper deals with a new system of aquaculture, i.e., a closed recirculating system for shrimp-mollusk polyculture. The culture system consisted of several shrimp ponds, a mollusk water-purifying pond and a reservoir. During the production cycle, water circulated between the shrimp and mollusk ponds, and the reservoir compensated for water loss from seepage and evaporation. Constricted tagelus, Sinonovacula constricta, was selected as the cultured mollusk, and Pacific white shrimp, Litopenaeus vannamei, as the cultured shrimp. The main managing measures during the production cycle were: setting and using the aerators; introducting the probiotic products timely into the shrimp ponds; adopting a “pen-closing” method for controlling shrimp viral epidemics; setting the flow diversion barriers in the mollusk pond to keep the circulating water flowing through the pond along a sine-like curve and serve as substrate for biofilm; no direct feeding was necessary for the cultured mollusk until the co-cultured shrimp was harvested; natural foods in the water from the shrimp ponds was used for their foods. Two sets of the system were used in the experiment in 2002 and satisfactory results were achieved. The average yield of the shrimp was 11 943.5 kg/hm2, and that of the mollusk was 16 965 kg/hm2. After converting the mollusk yield into shrimp yield at their market price ratio, the food coefficient of the entire system averaged at as low as 0.81. The water quality in the ponds was maintained at a desirable level and no viral epidemics were discovered during the production cycle.

  11. Photobacterium aquae sp. nov., isolated from a recirculating mariculture system.

    PubMed

    Liu, Ying; Liu, Liang-Zi; Song, Lei; Zhou, Yu-Guang; Qi, Fang-Jun; Liu, Zhi-Pei

    2014-02-01

    A Gram-staining-negative, heterotrophic, facultatively anaerobic bacterium, designated AE6(T), was isolated from a grouper (Epinephelus malabaricas) culture tank in a recirculating mariculture system located in Tianjin, China. Strain AE6(T) was able to grow at 15-40 °C (optimum, 30-35 °C), at pH 5.5-10.0 (optimum, pH 7.0-7.5) and in the presence of 0.5-7% (w/v) NaCl (optimum, 2-3%). It contained Q-8 as the predominant respiratory quinone, phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) as the major polar lipids and C(16 : 1)ω7c/C(16 : 1)ω6c (40.4%), C(18 : 1)ω7c (15.5%) and C(16 : 0) (13.5%) as the predominant cellular fatty acids. The genomic DNA G+C content was 47.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain AE6(T) belonged to the genus Photobacterium (94.2-96.8% of 16S rRNA gene sequence similarity) and formed a distinct phylogenetic lineage within the genus and exhibited the highest sequence similarity to Photobacterium aphoticum CECT 7614(T) (96.8%). Multilocus sequence analysis (MLSA) using four loci (gyrB, rpoA, pyrH and recA) also revealed that strain AE6(T) was phylogenetically related to the genus Photobacterium. Based on the phylogenetic, chemotaxonomic and phenotypic evidence, strain AE6(T) is considered to represent a novel species of the genus Photobacterium, for which the name Photobacterium aquae sp. nov. is proposed. The type strain is AE6(T) ( = CGMCC 1.12159(T) = JCM 18480(T)).

  12. The Louisiana ACES Student-built BalloonSat Program

    NASA Astrophysics Data System (ADS)

    Ellison, B.; Giammanco, J.; Guzik, T. G.; Johnson, K.; Wefel, J. P.

    The Aerospace Catalyst Experiences for Students (ACES) pilot project was funded at Louisiana State University by NASA's National Space Grant College and Fellowship program during the 2002-2003 academic year with the primary goal of giving students a true hands-on experience with project management, life-cycle, experiment construction, data collection, analysis and interpretation. In this project students design, build, fly and analyze the data returned from small payloads (typical dimensions 10 cm x 10 cm x 10 cm, typical weight ˜ 500 grams) carried up to ˜ 100,000 feet by a helium-filled latex sounding balloon. During the pilot project the 13 students that participated in the program, grouped in 4 teams, built payloads that included studies in atmospheric science, cosmic rays and remote sensing. These payloads were then launched from the NASA National Scientific Balloon Facility in Palestine, Texas on May 21, 2003. Most recently, the LaACES (Louisiana ACES) program has been selected for funding by NASA. During LaACES we will expand the pilot program to institutions across the state including developing student training materials, holding a workshop for institution representatives, awarding payload development grants to student teams, monitoring the progress of these teams and supporting the balloon flight of the completed payloads. Here we describe the ACES pilot, the outcomes, and plans for La ACES.

  13. Sequestering CO2 in the Built Environment

    NASA Astrophysics Data System (ADS)

    Constantz, B. R.

    2009-12-01

    Calera’s Carbonate Mineralization by Aqueous Precipitation (CMAP) technology with beneficial reuse has been called, “game-changing” by Carl Pope, Director of the Sierra Club. Calera offers a solution to the scale of the carbon problem. By capturing carbon into the built environment through carbonate mineralization, Calera provides a sound and cost-effective alternative to Geologic Sequestration and Terrestrial Sequestration. The CMAP technology permanently converts carbon dioxide into a mineral form that can be stored above ground, or used as a building material. The process produces a suite of carbonate-containing minerals of various polymorphic forms. Calera product can be substituted into blends with ordinary Portland cements and used as aggregate to produce concrete with reduced carbon, carbon neutral, or carbon negative footprints. For each ton of product produced, approximately half a ton of carbon dioxide can be sequestered using the Calera process. Coal and natural gas are composed of predominately istopically light carbon, as the carbon in the fuel is plant-derived. Thus, power plant CO2 emissions have relatively low δ13C values.The carbon species throughout the CMAP process are identified through measuring the inorganic carbon content, δ13C values of the dissolved carbonate species, and the product carbonate minerals. Measuring δ13C allows for tracking the flue gas CO2 throughout the capture process. Initial analysis of the capture of propane flue gas (δ13C ˜ -25 ‰) with seawater (δ13C ˜ -10 ‰) and industrial brucite tailings from a retired magnesium oxide plant in Moss Landing, CA (δ13C ˜ -7 ‰ from residual calcite) produced carbonate mineral products with a δ13C value of ˜ -20 ‰. This isotopically light carbon, transformed from flue gas to stable carbonate minerals, can be transferred and tracked through the capture process, and finally to the built environment. CMAP provides an economical solution to global warming by producing

  14. Mineral and organic compounds in leachate from landfill with concentrate recirculation.

    PubMed

    Talalaj, Izabela Anna

    2015-02-01

    The effect of a reverse osmosis concentrate recirculation on the mineral and organic compounds in a landfill leachate was investigated. Investigated was the quality of a leachate from two landfills operated for different periods (a 20-year-old Cell A and a 1-year-old Cell B), where the concentrate was recirculated. Examined were general parameters (conductivity, pH), organic compounds (biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic nitrogen, BOD/COD), and inorganic compounds (nitrogen ammonia, sulfite, sulfate, cyanide, boron, chloride, ferrous, zinc, chrome, copper). The findings from the first year of investigation showed that over the initial period of recirculation, the concentration of organic compounds (BOD, COD) increased, but after 6 months their values stabilized. It indicates that the concentrate recirculation accelerated organic decomposition, especially in the new landfill Cell. The analysis of inorganic parameters showed that recirculation landfills produce a leachate with a higher concentration of N-NH4, and Cl(-). In case of the old landfill Cell, an increase in B and Fe was also noticeable. These compounds are cyclically washed out from a waste dump and require an additional pretreatment in order to exclude them from recirculation cycle. The increased concentration of Cu, Zn, and Fe was noticed during the initial months of recirculation and in the season of intense atmospheric precipitation in the leachate from both Cells. Higher values of electro conductivity, Cl(-), N-NH4 (+), B, and Fe in the leachate from the old field indicate that the attenuation capacity of this landfill is close to exhaustion.

  15. 46 CFR 67.97 - United States built.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false United States built. 67.97 Section 67.97 Shipping COAST... DOCUMENTATION OF VESSELS Build Requirements for Vessel Documentation § 67.97 United States built. To be considered built in the United States a vessel must meet both of the following criteria: (a) All...

  16. 46 CFR 67.97 - United States built.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false United States built. 67.97 Section 67.97 Shipping COAST... DOCUMENTATION OF VESSELS Build Requirements for Vessel Documentation § 67.97 United States built. To be considered built in the United States a vessel must meet both of the following criteria: (a) All...

  17. 46 CFR 67.97 - United States built.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false United States built. 67.97 Section 67.97 Shipping COAST... DOCUMENTATION OF VESSELS Build Requirements for Vessel Documentation § 67.97 United States built. To be considered built in the United States a vessel must meet both of the following criteria: (a) All...

  18. 46 CFR 67.97 - United States built.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false United States built. 67.97 Section 67.97 Shipping COAST... DOCUMENTATION OF VESSELS Build Requirements for Vessel Documentation § 67.97 United States built. To be considered built in the United States a vessel must meet both of the following criteria: (a) All...

  19. 46 CFR 67.97 - United States built.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false United States built. 67.97 Section 67.97 Shipping COAST... DOCUMENTATION OF VESSELS Build Requirements for Vessel Documentation § 67.97 United States built. To be considered built in the United States a vessel must meet both of the following criteria: (a) All...

  20. 47 CFR 15.23 - Home-built devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Home-built devices. 15.23 Section 15.23 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES General § 15.23 Home-built... constructed from a kit, and are built in quantities of five or less for personal use. (b) It is...

  1. 47 CFR 15.23 - Home-built devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Home-built devices. 15.23 Section 15.23 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES General § 15.23 Home-built... constructed from a kit, and are built in quantities of five or less for personal use. (b) It is...

  2. Status of Centralized Environmental Creep Testing Facility Preparation and Upgrade

    SciTech Connect

    Ren, Weiju; Battiste, Rick

    2006-10-01

    Because the ASME Codes do not cover environmental issues that are crucial in the design and construction of VHTR system, investigation of long-term impure helium effects on metallurgical stability and properties becomes very important. The present report describes the development of centralized environmental creep testing facility, its close collaborations with the experiments in low velocity helium recirculation loop, important lessons learned, upgrades in system design in FY06, and current status of the development.

  3. The effect of upstream buildings on near-field pollutant dispersion in the built environment

    NASA Astrophysics Data System (ADS)

    Hajra, B.; Stathopoulos, T.; Bahloul, A.

    2011-09-01

    This paper examines the effects of near-field pollutant dispersion characteristics of upstream buildings in the built environment and compares them to the ASHRAE 2007 model. Wind tunnel simulations were performed for nine different building configurations for three exhaust momentum ratios ( M) and three stack heights ( hs). The effect of spacing ( S) between the buildings and stack location from the upwind edge of the emitting building ( X) were also investigated. Measurements of gas concentrations were performed on the roof and leeward wall of the emitting and upstream buildings. Data show that within the recirculation zone a change in along wind dimension of the upstream building has a negligible effect on the dilution of emissions from the downwind building. However, spacing between buildings and the height of the upstream building were found to be critical parameters in assessing plume dilution. The plume geometry is largely governed by the upwind dimensions of the upstream building. ASHRAE (2007) predicts lower dilution for all cases examined, leading to conservative or very conservative design. However, the ASHRAE 2007 cannot model the effect of upstream buildings, thus further investigation of its formulations is required. Guidelines for placement of intake and stack on the roof of the building to avoid problems of re-ingestion are discussed.

  4. Molecular Rotors Built in Porous Materials.

    PubMed

    Comotti, Angiolina; Bracco, Silvia; Sozzani, Piero

    2016-09-20

    Molecules and materials can show dynamic structures in which the dominant mechanism is rotary motion. The single mobile elements are defined as "molecular rotors" and exhibit special properties (compared with their static counterparts), being able in perspective to greatly modulate the dielectric response and form the basis for molecular motors that are designed with the idea of making molecules perform a useful mechanical function. The construction of ordered rotary elements into a solid is a necessary feature for such design, because it enables the alignment of rotors and the fine-tuning of their steric and dipolar interactions. Crystal surfaces or bulk crystals are the most suitable to adapt rotors in 2D or 3D arrangements and engineer juxtaposition of the rotors in an ordered way. Nevertheless, it is only in recent times that materials showing porosity and remarkably low density have undergone tremendous development. The characteristics of large free volume combine well with the virtually unhindered motion of the molecular rotors built into their structure. Indeed, the molecular rotors are used as struts in porous covalent and supramolecular architectures, spanning both hybrid and fully organic materials. The modularity of the approach renders possible a variety of rotor geometrical arrangements in both robust frameworks stable up to 850 K and self-assembled molecular materials. A nanosecond (fast dynamics) motional regime can be achieved at temperatures lower than 240 K, enabling rotor arrays operating in the solid state even at low temperatures. Furthermore, in nanoporous materials, molecular rotors can interact with the diffusing chemical species, be they liquids, vapors, or gases. Through this chemical intervention, rotor speed can be modulated at will, enabling a new generation of rotor-containing materials sensitive to guests. In principle, an applied electric field can be the stimulus for chemical release from porous materials. The effort needed to

  5. Consolidated Incineration Facility Tritium Emissions Monitoring

    SciTech Connect

    Dunn, D. L.; Aggus, J.R.

    1995-03-29

    The Savannah River Technology Center, a research and development facility at the US Department of Energy`s Savannah River Site, provides environmental and regulatory compliance support to onsite operations. A new consolidated Incinerator Facility at SRS is being built to treat hazardous and a combination of hazardous and radioactive (mixed) wastes.

  6. NETL's Hybrid Performance, or Hyper, facility

    ScienceCinema

    None

    2016-07-12

    NETL's Hybrid Performance, or Hyper, facility is a one-of-a-kind laboratory built to develop control strategies for the reliable operation of fuel cell/turbine hybrids and enable the simulation, design, and implementation of commercial equipment. The Hyper facility provides a unique opportunity for researchers to explore issues related to coupling fuel cell and gas turbine technologies.

  7. Fast Spatially Resolved Exhaust Gas Recirculation (EGR) Distribution Measurements in an Internal Combustion Engine Using Absorption Spectroscopy

    SciTech Connect

    Yoo, Jihyung; Prikhodko, Vitaly; Parks, James E.; Perfetto, Anthony; Geckler, Sam; Partridge, William P.

    2015-09-01

    One effective method of reducing NOx emissions while improving efficiency is exhaust gas recirculation (EGR) in internal combustion engines. But, insufficient mixing between fresh air and exhaust gas can lead to cycle-to-cycle and cylinder-to-cylinder nonuniform charge gas mixtures of a multi-cylinder engine, which can in turn reduce engine performance and efficiency. Furthermore, a sensor packaged into a compact probe was designed, built and applied to measure spatiotemporal EGR distributions in the intake manifold of an operating engine. The probe promotes the development of more efficient and higher-performance engines by resolving high-speed in situ CO2 concentration at various locations in the intake manifold. Our study employed mid-infrared light sources tuned to an absorption band of CO2 near 4.3 μm, an industry standard species for determining EGR fraction. The calibrated probe was used to map spatial EGR distributions in an intake manifold with high accuracy and monitor cycle-resolved cylinder-specific EGR fluctuations at a rate of up to 1 kHz.

  8. Fast spatially resolved exhaust gas recirculation (EGR) distribution measurements in an internal combustion engine using absorption spectroscopy.

    PubMed

    Yoo, Jihyung; Prikhodko, Vitaly; Parks, James E; Perfetto, Anthony; Geckler, Sam; Partridge, William P

    2015-09-01

    Exhaust gas recirculation (EGR) in internal combustion engines is an effective method of reducing NOx emissions while improving efficiency. However, insufficient mixing between fresh air and exhaust gas can lead to cycle-to-cycle and cylinder-to-cylinder non-uniform charge gas mixtures of a multi-cylinder engine, which can in turn reduce engine performance and efficiency. A sensor packaged into a compact probe was designed, built and applied to measure spatiotemporal EGR distributions in the intake manifold of an operating engine. The probe promotes the development of more efficient and higher-performance engines by resolving high-speed in situ CO2 concentration at various locations in the intake manifold. The study employed mid-infrared light sources tuned to an absorption band of CO2 near 4.3 μm, an industry standard species for determining EGR fraction. The calibrated probe was used to map spatial EGR distributions in an intake manifold with high accuracy and monitor cycle-resolved cylinder-specific EGR fluctuations at a rate of up to 1 kHz.

  9. Fast Spatially Resolved Exhaust Gas Recirculation (EGR) Distribution Measurements in an Internal Combustion Engine Using Absorption Spectroscopy

    DOE PAGES

    Yoo, Jihyung; Prikhodko, Vitaly; Parks, James E.; ...

    2015-09-01

    One effective method of reducing NOx emissions while improving efficiency is exhaust gas recirculation (EGR) in internal combustion engines. But, insufficient mixing between fresh air and exhaust gas can lead to cycle-to-cycle and cylinder-to-cylinder nonuniform charge gas mixtures of a multi-cylinder engine, which can in turn reduce engine performance and efficiency. Furthermore, a sensor packaged into a compact probe was designed, built and applied to measure spatiotemporal EGR distributions in the intake manifold of an operating engine. The probe promotes the development of more efficient and higher-performance engines by resolving high-speed in situ CO2 concentration at various locations in themore » intake manifold. Our study employed mid-infrared light sources tuned to an absorption band of CO2 near 4.3 μm, an industry standard species for determining EGR fraction. The calibrated probe was used to map spatial EGR distributions in an intake manifold with high accuracy and monitor cycle-resolved cylinder-specific EGR fluctuations at a rate of up to 1 kHz.« less

  10. Rendezvous facilities

    SciTech Connect

    Gehani, N.H.; Roome, W.D.

    1988-11-01

    The concurrent programming facilities in both Concurrent C and the Ada language are based on the rendezvous concept. Although these facilities are similar, there are substantial differences. Facilities in Concurrent C were designed keeping in perspective the concurrent programming facilities in the Ada language and their limitations. Concurrent C facilities have also been modified as a result of experience with its initial implementations. In this paper, the authors compare the concurrent programming facilities in Concurrent C and Ada, and show that it is easier to write a variety of concurrent programs in Concurrent C than in Ada.

  11. Anaerobic degradation of dairy wastewater in intermittent UASB reactors: influence of effluent recirculation.

    PubMed

    Couras, C S; Louros, V L; Gameiro, T; Alves, N; Silva, A; Capela, M I; Arroja, L M; Nadais, H

    2015-01-01

    This work studied the influence of effluent recirculation upon the kinetics of anaerobic degradation of dairy wastewater in the feedless phase of intermittent upflow anaerobic sludge bed (UASB) reactors. Several laboratory-scale tests were performed with different organic loads in closed circuit UASB reactors inoculated with adapted flocculent sludge. The data obtained were used for determination of specific substrate removal rates and specific methane production rates, and adjusted to kinetic models. A high initial substrate removal was observed in all tests due to adsorption of organic matter onto the anaerobic biomass which was not accompanied by biological substrate degradation as measured by methane production. Initial methane production rate was about 45% of initial soluble and colloidal substrate removal rate. This discrepancy between methane production rate and substrate removal rate was observed mainly on the first day of all experiments and was attenuated on the second day, suggesting that the feedless period of intermittent UASB reactors treating dairy wastewater should be longer than one day. Effluent recirculation expressively raised the rate of removal of soluble and colloidal substrate and methane productivity, as compared with results for similar assays in batch reactors without recirculation. The observed bed expansion was due to the biogas production and the application of effluent recirculation led to a sludge bed contraction after all the substrates were degraded. The settleability of the anaerobic sludge improved by the introduction of effluent recirculation this effect being more pronounced for the higher loads.

  12. Performance of Water Recirculation Loop Maintenance Components for the Advanced Spacesuit Water Membrane Evaporator

    NASA Technical Reports Server (NTRS)

    Rector, Tony; Peyton, Barbara M.; Steele, John W.; Makinen, Janice; Bue, Grant C.; Campbell, Colin

    2014-01-01

    Water loop maintenance components to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop have undergone a comparative performance evaluation with a recirculating control loop which had no water quality maintenance. Results show that periodic water maintenance can improve performance of the SWME. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage of this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing sublimator technology. The driver for the evaluation of water recirculation maintenance components was to enhance the robustness of the SWME through the leveraging of fluid loop management lessons learned from the International Space Station (ISS). A patented bed design that was developed for a United Technologies Aerospace System military application provided a low pressure drop means for water maintenance in the SWME recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance cycle included the use of a biocide delivery component developed for the ISS to introduce a biocide in a microgravity compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.

  13. PAINT SPRAY BOOTH DESIGN USING RECIRCULATION/PARTITIONING VENTILATION

    EPA Science Inventory

    Many spray painting facility operators have been attempting to reduce the discharge of volatile organic compounds (VOCs) from paint spray booths to the atmosphere. Some have been able to convert to lower VOC containing paints and coatings such as powder coating, waterborne coatin...

  14. Noscapine recirculates enterohepatically and induces self-clearance.

    PubMed

    Mukkavilli, Rao; Gundala, Sushma R; Yang, Chunhua; Jadhav, Gajanan R; Vangala, Subrahmanyam; Reid, Michelle D; Aneja, Ritu

    2015-09-18

    Noscapine (Nos), an antitussive benzylisoquinoline opium alkaloid, is a non-toxic tubulin-binding agent currently in Phase II clinical trials for cancer chemotherapy. While preclinical studies have established its tumor-inhibitory properties in various cancers, poor absorptivity and rapid first-pass metabolism producing several uncharacterized metabolites for efficacy, present an impediment in translating its efficacy in humans. Here we report novel formulations of Nos in combination with dietary agents like capsaicin (Cap), piperine (Pip), eugenol (Eu) and curcumin (Cur) known for modulating Phase I and II drug metabolizing enzymes. In vivo pharmacokinetic (PK), organ toxicity evaluation of combinations, microsomal stability and in vitro cytochrome P450 (CYP) inhibition effects of Nos, Cap and Pip using human liver microsomes were performed. Single-dose PK screening of combinations revealed that the relative exposure of Nos (2 μg h/mL) was enhanced by 2-fold (4 μg h/mL) by Cap and Pip and their plasma concentration-time profiles showed multiple peaking phenomena for Nos indicating enterohepatic recirculation or differential absorption from intestine. CYP inhibition studies confirmed that Nos, Cap and Pip are not potent CYP inhibitors (IC50>1 μM). Repeated oral dosing of Nos, Nos+Cap and Nos+Pip showed lower exposure (Cmax and AUClast) of Nos on day 7 compared to day 1. Nos Cmax decreased from 3087 ng/mL to 684 ng/mL and AUClast from 1024 ng h/mL to 508 ng h/mL. In presence of Cap and Pip, the decrease in Cmax and AUClast of Nos was similar. This may be due to potential enzyme induction leading to rapid clearance of Nos as the trend was observed in Nos alone group also. The lack of effect on intrinsic clearance of Nos suggests that the potential drug biotransformation modulators employed in this study did not contribute toward increased exposure of Nos on repeated dosing. We envision that Nos-induced enzyme induction could alter the therapeutic efficacy of co

  15. Health Facilities

    MedlinePlus

    Health facilities are places that provide health care. They include hospitals, clinics, outpatient care centers, and specialized care centers, ... psychiatric care centers. When you choose a health facility, you might want to consider How close it ...

  16. The QUASAR facility

    NASA Astrophysics Data System (ADS)

    Gates, David

    2013-10-01

    The QUAsi-Axisymmetric Research (QUASAR) stellarator is a new facility which can solve two critical problems for fusion, disruptions and steady-state, and which provides new insights into the role of magnetic symmetry in plasma confinement. If constructed it will be the only quasi-axisymmetric stellarator in the world. The innovative principle of quasi-axisymmetry (QA) will be used in QUASAR to study how ``tokamak-like'' systems can be made: 1) Disruption-free, 2) Steady-state with low recirculating power, while preserving or improving upon features of axisymmetric tokamaks, such as 1) Stable at high pressure simultaneous with 2) High confinement (similar to tokamaks), and 3) Scalable to a compact reactor Stellarator research is critical to fusion research in order to establish the physics basis for a magnetic confinement device that can operate efficiently in steady-state, without disruptions at reactor-relevant parameters. The two large stellarator experiments - LHD in Japan and W7-X under construction in Germany are pioneering facilities capable of developing 3D physics understanding at large scale and for very long pulses. The QUASAR design is unique in being QA and optimized for confinement, stability, and moderate aspect ratio (4.5). It projects to a reactor with a major radius of ~8 m similar to advanced tokamak concepts. It is striking that (a) the EU DEMO is a pulsed (~2.5 hour) tokamak with major R ~ 9 m and (b) the ITER physics scenarios do not presume steady-state behavior. Accordingly, QUASAR fills a critical gap in the world stellarator program. This work supported by DoE Contract No. DEAC02-76CH03073.

  17. Environmental performance of air staged combustor with flue gas recirculation to burn coal/biomass

    SciTech Connect

    Anuar, S.H.; Keener, H.M.

    1995-12-31

    The environmental and thermal performance of a 1.07 m diameter, 440 kW atmospheric fluidized bed combustor operated at 700{degrees}C-920{degrees}C and burning coal was studied. Flue gas recirculation was incorporated to enhance the thermal performance and air staging was used to control emissions of SO{sub 2}, CO, NO{sub x} and N{sub 2}O. Studies focused on the effect of excess air, firing rate, and use of sorbent on system performance. The recirculation-staging mode with limestone had the highest thermal efficiency (0.67) using the firing equation. Emission data showed that flue gas recirculation (ratio of 0.7) significantly reduced NO{sub x} emissions; and that use of limestone sorbent at a Ca/S ratio of 3 reduced SO{sub 2} emissions by 64% to approximately 0.310 g/MJ.

  18. Investigation of hydrocarbon oil transformation by gliding arc discharge: comparison of batch and recirculated configurations

    NASA Astrophysics Data System (ADS)

    Whitehead, J. Christopher; Prantsidou, Maria

    2016-04-01

    The degradation of liquid dodecane was studied in a gliding arc discharge (GAD) of humid argon or nitrogen. A batch or recirculating configuration was used. The products in the gaseous and liquid phase were analysed by infrared and chromatography and optical emission spectroscopy was used to identify the excited species in the discharge. The best degradation performance comes from the use of humid N2 but a GAD of humid argon produces fewer gas-phase products but more liquid-phase end-products. A wide range of products such as heavier saturated or unsaturated hydrocarbons both aliphatic and aromatic, and oxidation products mainly alcohols, but also aldehydes, ketones and esters are produced in the liquid-phase. The recirculating treatment mode is more effective than the batch mode increasing the reactivity and changing the product selectivities. Overall, the study shows promising results for the organic liquid waste treatment, especially in the recirculating mode.

  19. Saponification pretreatment and solids recirculation as a new anaerobic process for the treatment of slaughterhouse waste.

    PubMed

    Affes, R; Palatsi, J; Flotats, X; Carrère, H; Steyer, J P; Battimelli, A

    2013-03-01

    Different configurations of anaerobic process, adapted to the treatment of solid slaughterhouse fatty waste, were proposed and evaluated in this study. The tested configurations are based on the combination of anaerobic digestion with/without waste saponification pretreatment (70 °C during 60 min) and with/without recirculation of the digestate solid fraction (ratio=20% w/w). After an acclimation period of substrate pulses-feeding cycles, the reactors were operated in a semi-continuous feeding mode, increasing organic loading rates along experimental time. The degradation of the raw substrate was shown to be the bottleneck of the whole process, obtaining the best performance and process yields in the reactor equipped with waste pretreatment and solids recirculation. Saponification promoted the emulsification and bioavailability of solid fatty residues, while recirculation of solids minimized the substrate/biomass wash-out and induced microbial adaptation to the treatment of fatty substrates.

  20. Recurrent amoebic gill infestation in rainbow trout cultured in a semiclosed water recirculation system

    USGS Publications Warehouse

    Noble, A.C.; Herman, R.L.; Noga, E.J.; Bullock, G.L.

    1997-01-01

    Five lots of commercially purchased juvenile rainbow trout Oncorhynchus mykiss (17-44 g) stocked in a continuous-production water recirculation system became infested with gilt amoebae. The amoebae were introduced into the recirculation system, as evidenced by their presence on gills of fish held in quarantine tanks. Based on their morphology, as seen in histological sections and by electron microscopy, the amoebae appeared to be more closely related to the family Cochliopodiidae than to other taxa of free living amoebae. Attempts to culture the amoebae in different media, at different temperatures of incubation, and in fish cell culture were not successful. Initial treatment of the recirculation system with formalin at 167 parts per million (ppm) for 1 h eliminated amoebae from the gills. Subsequent treatments of the entire system with formalin at 50-167 ppm reduced the intensity of further infestations.

  1. Multi-Point Interferometric Rayleigh Scattering using Dual-Pass Light Recirculation

    NASA Technical Reports Server (NTRS)

    Bivolaru, Daniel; Danehy, Paul M.; Cutler, Andrew D.

    2008-01-01

    This paper describes for the first time an interferometric Rayleigh scattering system using dual-pass light recirculation (IRS-LR) capable of simultaneously measuring at multiple points two orthogonal components of flow velocity in combustion flows using single shot laser probing. An additional optical path containing the interferometer input mirror, a quarter-wave plate, a polarization dependent beam combiner, and a high reflectivity mirror partially recirculates the light that is rejected by the interferometer. Temporally- and spatially-resolved acquisitions of Rayleigh spectra in a large-scale combustion-heated supersonic axi-symmetric jet were performed to demonstrate the technique. Recirculating of Rayleigh scattered light increases the number of photons analyzed by the system up to a factor of 1.8 compared with previous configurations. This is equivalent to performing measurements with less laser energy or performing measurements with the previous system in gas flows at higher temperatures.

  2. Physics issues in the design of a recirculating induction accelerator for heavy ion fusion

    SciTech Connect

    Barnard, J.J.; Newton, M.A.; Reginato, L.L.; Sharp, W.M.; Yu, S.S.

    1991-04-15

    A substantial savings in size and cost over a linear machine may be achieved in an induction accelerator in which a heavy ion beam makes many (< {approximately} 50) passes through one or more circular induction accelerators. We examine how the requirement of high beam quality and the requirement of pulse simultaneity at the target constrain the design of such an accelerator. Some of the issues that we have considered include beam interactions with residual gas, beam-beam charge exchange, emittance growth around bends, and beam instabilities. We show some of the interplay between maximization of beam quality and recirculator efficiency, and the minimization of recirculator cost, in arriving at a recirculator design. 9 refs., 1 fig.

  3. Method and apparatus for control of coherent synchrotron radiation effects during recirculation with bunch compression

    DOEpatents

    Douglas, David R; Tennant, Christopher

    2015-11-10

    A modulated-bending recirculating system that avoids CSR-driven breakdown in emittance compensation by redistributing the bending along the beamline. The modulated-bending recirculating system includes a) larger angles of bending in initial FODO cells, thereby enhancing the impact of CSR early on in the beam line while the bunch is long, and 2) a decreased bending angle in the final FODO cells, reducing the effect of CSR while the bunch is short. The invention describes a method for controlling the effects of CSR during recirculation and bunch compression including a) correcting chromatic aberrations, b) correcting lattice and CSR-induced curvature in the longitudinal phase space by compensating T.sub.566, and c) using lattice perturbations to compensate obvious linear correlations x-dp/p and x'-dp/p.

  4. The crop growth research chamber: A ground-based facility for CELSS research

    NASA Technical Reports Server (NTRS)

    Bubenheim, David L.

    1990-01-01

    A ground based facility for the study of plant growth and development under stringently controlled environments is being developed by the Closed Ecological Life Support System (CELSS) program at the Ames Research Center. Several Crop Growth Research Chambers (CGRC) and laboratory support equipment provide the core of this facility. The CGRC is a closed (sealed) system with a separate recirculating atmosphere and nutrient delivery systems. The atmospheric environment, hydroponic environment, systems controls, and data acquisition are discussed.

  5. Extent of flow recirculation governs expression of atherosclerotic and thrombotic biomarkers in arterial bifurcations

    PubMed Central

    Martorell, Jordi; Santomá, Pablo; Kolandaivelu, Kumaran; Kolachalama, Vijaya B.; Melgar-Lesmes, Pedro; Molins, José J.; Garcia, Lawrence; Edelman, Elazer R.; Balcells, Mercedes

    2014-01-01

    Aims Atherogenesis, evolution of plaque, and outcomes following endovascular intervention depend heavily on the unique vascular architecture of each individual. Patient-specific, multiscale models able to correlate changes in microscopic cellular responses with relevant macroscopic flow, and structural conditions may help understand the progression of occlusive arterial disease, providing insights into how to mitigate adverse responses in specific settings and individuals. Methods and results Vascular architectures mimicking coronary and carotid bifurcations were derived from clinical imaging and used to generate conjoint computational meshes for in silico analysis and biocompatible scaffolds for in vitro models. In parallel with three-dimensional flow simulations, geometrically realistic scaffolds were seeded with human smooth muscle cells (SMC) or endothelial cells and exposed to relevant, physiological flows. In vitro surrogates of endothelial health, atherosclerotic progression, and thrombosis were locally quantified and correlated best with an quantified extent of flow recirculation occurring within the bifurcation models. Oxidized low-density lipoprotein uptake, monocyte adhesion, and tissue factor expression locally rose up to three-fold, and phosphorylated endothelial nitric oxide synthase and Krüppel-like factor 2 decreased up to two-fold in recirculation areas. Isolated testing in straight-tube idealized constructs subject to static, oscillatory, and pulsatile conditions, indicative of different recirculant conditions corroborated these flow-mediated dependencies. Conclusions Flow drives variations in vascular reactivity and vascular beds. Endothelial health was preserved by arterial flow but jeopardized in regions of flow recirculation in a quasi-linear manner. Similarly, SMC exposed to flow were more thrombogenic in large recirculating regions. Health, thrombosis, and atherosclerosis biomarkers correlate with the extent of recirculation in vascular

  6. Methane emissions from MSW landfill with sandy soil covers under leachate recirculation and subsurface irrigation

    NASA Astrophysics Data System (ADS)

    Zhang, Houhu; He, Pinjing; Shao, Liming

    CH 4 emissions and leachate disposal are recognized as the two major concerns in municipal solid waste (MSW) landfills. Recently, leachate recirculation was attempted to accelerate land-filled waste biodegradation and thus enhanced landfill gas generation. Leachate irrigation was also conducted for volume reduction effectively. Nevertheless, the impacts of leachate recirculation and irrigation on landfill CH 4 emissions have not been previously reported. A field investigation of landfill CH 4 emissions was conducted on selected sandy soil cover with leachate recirculation and subsurface irrigation based on whole year around measurement. The average CH 4 fluxes were 311±903, 207±516, and 565±1460 CH 4 m -2 h -1 from site A without leachate recirculation and subsurface irrigation, lift B2 with leachate subsurface irrigation, and lift B1 with both leachate recirculation and subsurface irrigation, respectively. Both gas recovery and cover soil oxidation minimized CH 4 emissions efficiently, while the later might be more pronounced when the location was more than 5 m away from gas recovery well. After covered by additional clay soil layer, CH 4 fluxes dropped by approximately 35 times in the following three seasons compared to the previous three seasons in lift B2. The diurnal peaks of CH 4 fluxes occurred mostly followed with air or soil temperature in the daytimes. The measured CH 4 fluxes were much lower than those of documented data from the landfills, indicating that the influences of leachate recirculation and subsurface irrigation on landfill CH 4 emissions might be minimized with the help of a well-designed sandy soil cover. Landfill cover composed of two soil layers (clay soil underneath and sandy soil above) is suggested as a low-cost and effective alternative to minimize CH 4 emissions.

  7. Component technologies for a recirculating linac free-electron laser

    NASA Astrophysics Data System (ADS)

    Litvinenko, Vladimir N.; Madey, John M. J.; Vinokurov, Nikolai A.

    1994-05-01

    The key component technologies required for a high average power free-electron laser (FEL) are described. Some basic aspects of approaches for high average power (scalable to megawatt level) accelerators and FELs are presented. A short description of the Novosibirsk 100 kW average power near infrared (IR) FEL driven by a race-track microtron-recuperator is given. The current status and plans for this facility are provided by Institute of Nuclear Physics (Novosibirsk).

  8. Heat and mass transfer in turbulent flows with several recirculated flow eddies

    NASA Astrophysics Data System (ADS)

    Baake, E.; Nacke, B.; Jakovics, A.; Umbrashko, A.

    2001-06-01

    Numerical modeling of the concentration and temperature distribution in axial symmetrical systems with several recirculated flow eddies, which is based on various 2D stationary k-ɛ models and commercial codes, e.g. ANSYS and FLUENT, leads to results, which are significantly different from experimental data. Therefore additional user-defined subroutines were included in the commercial program code to improve the turbulent heat and mass transfer in the zone between the recirculated flow eddies. In addition transient 3D calculations were performed to investigate scientifically the flow dynamics. Figs 9, Refs 8.

  9. Non-premixed conditions in the flameholding recirculation region behind a step in supersonic flow

    NASA Astrophysics Data System (ADS)

    Thakur, Amit

    Flameholding in supersonic flow depends on local conditions in the recirculation region, and on mass transfer into and out of this region. Large gradients in local gas composition and temperature exist in the recirculation region. Hence, stability parameter correlations developed for premixed flames cannot be used to determine blowout stability limits for non-premixed flames encountered in practical devices. In the present study, mixture samples were extracted at different locations in the recirculation region and the shear layer formed behind a rearward-facing step in supersonic flow, and analyzed by mass spectrometry to determine the species concentration distribution in the region. The point-wise mass spectrometer measurements were complemented by acetone planar laser-induced fluorescence (PLIF) measurements to get a planar distribution of fuel mole fraction in the recirculation region. Non-reacting flow tests and combustion experiments were performed by varying various fuel related parameters such as injection location, injection pressure and fuel type. Fuel injection upstream of the step was not effective in supplying enough fuel to the recirculation region and did not sustain the flame in combustion experiments. Fuel injection at the step base was effective in sustaining the flame. For base injection, the local fuel mole fraction in the recirculation region determined from experiments was an order of magnitude higher than the global fuel mole fraction based on total moles of air flowing through the test section and total fuel injected in the test section. This suggests substantial difference in flame stability curve for non-premixed conditions in the scramjet engine compared to premixed flow. For base injection, fuel remained in the recirculation region even at higher injection pressure. Due to slower diffusion rate, the heavier fuel had higher local mole fraction in the recirculation region compared to lighter fuel for a unit global fuel mole fraction

  10. A computer model of the energy-current loss instabilities in a recirculating accelerator system

    NASA Astrophysics Data System (ADS)

    Edighoffer, J. A.; Kim, K.-J.

    1995-04-01

    The computer program called ESRA (energy stability in a recirculating accelerator FELs) has been written to model bunches of particles in longitudinal phase space traversing a recirculating accelerator and the associated rf changes and aperture current losses. This code addresses stability issues and determines the transport, noise, feedback and other parameters for which these FEL systems are stable or unstable. A representative system is modeled, the Novosibirisk high power FEL race-track microtron for photochemical research. The system is stable with prudent choice of parameters.

  11. Hybrid heat exchange for the compression capture of CO2 from recirculated flue gas

    SciTech Connect

    Oryshchyn, Danylo B.; Ochs, Thomas L.; Summers, Cathy A.

    2004-01-01

    An approach proposed for removal of CO2 from flue gas cools and compresses a portion of a recirculated flue-gas stream, condensing its volatile materials for capture. Recirculating the flue gas concentrates SOx, H2O and CO2 while dramatically reducing N2 and NOx, enabling this approach, which uses readily available industrial components. A hybrid system of indirect and direct-contact heat exchange performs heat and mass transfer for pollutant removal and energy recovery. Computer modeling and experimentation combine to investigate the thermodynamics, heat and mass transfer, chemistry and engineering design of this integrated pollutant removal (IPR) system.

  12. 310 Facility chemical specifications

    SciTech Connect

    Hagerty, K.J.

    1997-05-21

    The 300 area Treated Effluent Disposal Facility (TEDF) was designed and built to treat the waste water from the 300 area process sewer system. Several treatment technologies are employed to remove the trace quantities of contaminants in the stream, including iron coprecipitation, clarification, filtration, ion exchange, and ultra violet light/hydrogen peroxide oxidation of organics. The chemicals that will be utilized in the treatment process are hydrogen peroxide, sulfuric acid, sodium hydroxide, and ferric chloride. This document annotates the required chemical characteristics of TEDF bulk chemicals as well as the criteria that were used to establish these criteria. The chemical specifications in appendix B are generated from this information.

  13. Engine Air Intake Manifold Having Built In Intercooler

    DOEpatents

    Freese, V, Charles E.

    2000-09-12

    A turbocharged V type engine can be equipped with an exhaust gas recirculation cooler integrated into the intake manifold, so as to achieve efficiency, cost reductions and space economization improvements. The cooler can take the form of a tube-shell heat exchanger that utilizes a cylindrical chamber in the air intake manifold as the heat exchanger housing. The intake manifold depends into the central space formed by the two banks of cylinders on the V type engine, such that the central space is effectively utilized for containing the manifold and cooler.

  14. Life Cycle Assessment of LEED versus Conventionally Built Residential Units

    DTIC Science & Technology

    2011-03-24

    construction documents, a hybrid LCA was used to quantify and compare the environmental impact of energy efficient homes built at Keesler AFB to... construction documents, the hybrid LCA was used to quantify and compare the environmental impact of energy efficient homes built at 12 Keesler AFB to...conventionally built homes, this study employed a hybrid LCA and energy simulation. These energy efficient homes have a 16% less environmental impact

  15. An evaluation of a micro programmable logic controller for oxygen monitoring and control in tanks of a recirculating aquaculture system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Control of dissolved gases, especially oxygen is an essential component of recirculating aquaculture systems. The use of pure oxygen in a recirculating aquaculture system creates supersaturated concentrations of dissolved oxygen and can reduce fish production costs by supporting greater fish and fee...

  16. Use of a micro programmable logic controller for oxygen monitoring and control in multiple tanks of a recirculating aquaculture system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In intensive recirculating aquaculture systems the use of supplemental oxygen, specifically pure liquid oxygen, increases the mass of fish that can be supported and eliminates oxygen as a major limiting factor to a system’s carrying capacity. The use of pure oxygen in a recirculating aquaculture sys...

  17. 5. Conveyors 'C' through 'K' (built 1940) south of Station, ...

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

    5. Conveyors 'C' through 'K' (built 1940) south of Station, looking northeast from hurricane barrier. - Manchester Street Generating Station, Conveyors, 460 Eddy Street, Providence, Providence County, RI

  18. Microbial community distribution and extracellular enzyme activities in leach bed reactor treating food waste: effect of different leachate recirculation practices.

    PubMed

    Xu, Su Yun; Karthikeyan, Obuli P; Selvam, Ammaiyappan; Wong, Jonathan W C

    2014-09-01

    This study aimed at understanding the relationship between microbial community and extracellular enzyme activities of leach bed reactor (LBR) treating food waste under different leachate recirculation practices (once per day and continuous) and liquid to solid (L/S) ratios (1:1 and 0.5:1). Microbial community analysis using PCR-DGGE revealed that Lactobacillus sp., Bifidobacter sp., and Proteobacteria were the most abundant species. Number of phylotypes was higher in LBRs with intermittent recirculation; whereas, lower number of phylotypes dominated by the key players of degradation was observed with continuous recirculation. The L/S ratio of 1:1 significantly enhanced the volatile solids removal compared with 0.5:1; however, this effect was insignificant under once a day leachate recirculation. Continuous leachate recirculation with 1:1 L/S ratio significantly improved the organic leaching (240 g COD/kgvolatile solid) and showed distinct extracellular enzyme activities suitable for food waste acidogenesis.

  19. Simulation studies of a XUV/soft X-ray harmonic-cascade FEL for the proposed LBNL recirculating linac*

    SciTech Connect

    Fawley, W.M.; Barletta, W.A.; Corlett, J.N.; Zholents, A.

    2003-06-02

    Presently there is significant interest at LBNL in designing and building a facility for ultrafast (i.e. femtosecond time scale) x-ray science based upon a superconducting, recirculating RF linac (see Corlett et al. for more details). In addition to producing synchrotron radiation pulses in the 1-15 keV energy range, we are also considering adding one or more free-electron laser (FEL) beamlines using a harmonic cascade approach to produce coherent XUV soft X-ray emission beginning with a strong input seed at {approx}200 nm wavelength obtained from a ''conventional'' laser. Each cascade is composed of a radiator together with a modulator section, separated by a magnetic chicane. The chicane temporally delays the electron beam pulse in order that a ''virgin'' pulse region (with undegraded energy spread) be brought into synchronism with the radiation pulse, which together then undergo FEL action in the modulator. We present various results obtained with the GINGER simulation code examining final output sensitivity to initial electron beam parameters. We also discuss the effects of spontaneous emission and shot noise upon this particular cascade approach which can limit the final output coherence.

  20. Back to the Roots: The Integration of a Constructed Wetland into a Recirculating Hatchery - A Case Study

    PubMed Central

    Buřič, Miloš; Bláhovec, Josef; Kouřil, Jan

    2015-01-01

    Aquaculture is currently one of the fastest growing food-producing sectors, accounting for around 50% of the world's food fish. Limited resources, together with climatic change, have stimulated the search for solutions to support and sustain the production of fish as a nutritious food. The integration of a constructed wetland (CW) into a recirculating hatchery (RHS) was evaluated with respect to its economic feasibility and environmental impact. The outcome of eight production cycles showed the potential of CW integration for expanded production without increased operation costs or environmental load. Concretely, the use of constructed wetland allows the rearing about 40% more fish biomass, resulting in higher production and profitability. The low requirements for space, fresh water, and energy enable the establishment of such systems almost anywhere. Constructed wetlands could enhance the productivity of existing small scale facilities, as well as larger systems, to address economic and environmental issues in aquaculture. Such systems have potential to be sustainable in the context of possible future climate change and resource limitations. PMID:25853416

  1. Developing Best Practices for Capturing As-Built Building Information Models (BIM) for Existing Facilities

    DTIC Science & Technology

    2010-08-01

    allowed the BIM developer to reliable place hyperlinked 16 markers within rooms, create “ clickable ” layers that could be activated/deactivated, and...The GRA measured both the performance of the field crew as well as the crew’s reaction to the technologies employed. In the field, the GRA...load questionnaire. This task-load survey measures the users’ reaction to the technologies, demands, and conditions related to the tasks they have

  2. 49 CFR 41.117 - Buildings built with Federal assistance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Buildings built with Federal assistance. 41.117 Section 41.117 Transportation Office of the Secretary of Transportation SEISMIC SAFETY § 41.117 Buildings built with Federal assistance. (a) Each DOT Operating Administration assisting in the financing, through Federal grants or loans, or...

  3. 12. Ore unloading dock, looking south. Dock, built in 1908, ...

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

    12. Ore unloading dock, looking south. Dock, built in 1908, featured two 10-ton-capacity Hulett unloaders (shown here) built by the Wellman-Seaver-Morgan Co. of Cleveland. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

  4. Transformative Learning: Innovating Sustainability Education in Built Environment

    ERIC Educational Resources Information Center

    Iyer-Raniga, Usha; Andamon, Mary Myla

    2016-01-01

    Purpose: This paper aims to evaluate how transformative learning is key to innovating sustainability education in the built environment in the region's universities, in addition to reporting on the research project undertaken to integrate sustainability thinking and practice into engineering/built environment curricula in Asia-Pacific…

  5. Achromatic recirculated chicane with fixed geometry and independently variable path length and momentum compaction

    DOEpatents

    Douglas, David R.; Neil, George R.

    2005-04-26

    A particle beam recirculated chicane geometry that, through the inducement of a pair of 180 degree bends directed by the poles of a pair of controllable magnetic fields allows for variation of dipole position, return loop radii and steering/focussing, thereby allowing the implementation of independent variation of path length and momentum compaction.

  6. Low-dose hydrogen peroxide application in closed recirculating aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of the present work was to simulate water treatment practice with hydrogen peroxide (HP) in recirculating aquaculture systems (RAS). Six identical 1700 L pilot scale RAS were divided into two experimental groups based on daily feed allocation and were operated under constant conditions durin...

  7. Evaluation of commercial marine fish feeds for production of juvenile cobia in recirculating aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of feeding three commercially available diets manufactured by three U.S. feed companies on production characteristics and body composition of juvenile cobia Rachycentron canadum reared in recirculating aquaculture systems (RAS) was evaluated in a 57 d growth trial. Juvenile cobia (26.7 +...

  8. Experimental Bleaching of a Reef-Building Coral Using a Simplified Recirculating Laboratory Exposure System

    EPA Science Inventory

    Determining stressor-response relationships in reef building corals is a critical need for researchers because of global declines in coral reef ecosystems. A simplified recirculating coral exposure system for laboratory testing of a diversity of species and morphologies of reef b...

  9. Suction-recirculation device for stabilizing particle flows within a solar powered solid particle receiver

    DOEpatents

    Kolb, Gregory J [Albuquerque, NM

    2012-02-07

    A suction-recirculation device for stabilizing the flow of a curtain of blackened heat absorption particles falling inside of a solar receiver with an open aperture. The curtain of particles absorbs the concentrated heat from a solar mirror array reflected up to the receiver on a solar power tower. External winds entering the receiver at an oblique angle can destabilize the particle curtain and eject particles. A fan and ductwork is located behind the back wall of the receiver and sucks air out through an array of small holes in the back wall. Any entrained particles are separated out by a conventional cyclone device. Then, the air is recirculated back to the top of the receiver by injecting the recycled air through an array of small holes in the receiver's ceiling and upper aperture front wall. Since internal air is recirculated, heat losses are minimized and high receiver efficiency is maintained. Suction-recirculation velocities in the range of 1-5 m/s are sufficient to stabilize the particle curtain against external wind speeds in excess of 10 m/s.

  10. Gas transfer rates from airlifts used for concurrent aeration, carbon dioxide stripping, and recirculation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Airlifts simplify recirculating aquaculture systems and can potentially reduce capital costs and minimize maintenance issues. Airlifts have the ability to move and aerate water as well as degass the water of any carbon dioxide. This study evaluated the oxygen transfer and carbon dioxide removal abil...

  11. Multi-point optimization of recirculation flow type casing treatment in centrifugal compressors

    NASA Astrophysics Data System (ADS)

    Tun, Min Thaw; Sakaguchi, Daisaku

    2016-06-01

    High-pressure ratio and wide operating range are highly required for a turbocharger in diesel engines. A recirculation flow type casing treatment is effective for flow range enhancement of centrifugal compressors. Two ring grooves on a suction pipe and a shroud casing wall are connected by means of an annular passage and stable recirculation flow is formed at small flow rates from the downstream groove toward the upstream groove through the annular bypass. The shape of baseline recirculation flow type casing is modified and optimized by using a multi-point optimization code with a metamodel assisted evolutionary algorithm embedding a commercial CFD code CFX from ANSYS. The numerical optimization results give the optimized design of casing with improving adiabatic efficiency in wide operating flow rate range. Sensitivity analysis of design parameters as a function of efficiency has been performed. It is found that the optimized casing design provides optimized recirculation flow rate, in which an increment of entropy rise is minimized at grooves and passages of the rotating impeller.

  12. Pilot-scale study of powdered activated carbon recirculation for micropollutant removal.

    PubMed

    Meinel, F; Sperlich, A; Jekel, M

    Adsorption onto powdered activated carbon (PAC) is a promising technique for the removal of organic micropollutants (OMPs) from treated wastewater. To enhance the adsorption efficiency, PAC is recycled back into the adsorption stage. This technique was examined in pilot scale in comparison to a reference without recirculation. Coagulation with Fe(3+) was carried out simultaneously to adsorption. Extensive OMP measurements showed that recirculation significantly increased OMP eliminations. Thus, significant PAC savings were feasible. The PAC concentration in the contact reactor proved to be an important operating parameter that can be surrogated by the easily measurable total suspended solids (TSS) concentration. OMP eliminations increased with increasing TSS concentrations. At 20 mg PAC L(-1) and 2.8 g TSS L(-1) in the contact reactor, well-adsorbable carbamazepine was eliminated by 97%, moderately adsorbable diclofenac was eliminated by 92% and poorly-adsorbable acesulfame was eliminated by 54% in comparison to 49%, 35% and 18%, respectively, without recirculation. The recirculation system represents an efficient technique, as the PAC's adsorption capacity is practically completely used. Small PAC dosages yield high OMP eliminations. Poorly-adsorbable gabapentin was eliminated to an unexpectedly high degree. A laboratory-scale biomass inhibition study showed that aerobic biodegradation removed gabapentin in addition to adsorption.

  13. Nitrate removal effectiveness of fluidized sulfur-based autotrophic denitrification biofilters for recirculating aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is a need to develop practical methods to reduce nitrate -nitrogen loads from recirculating aqua-culture systems to facilitate increased food protein production simultaneously with attainment of water quality goals. The most common wastewater denitrification treatment systems utilize methanol-...

  14. Performance of two-stage vegetable waste anaerobic digestion depending on varying recirculation rates.

    PubMed

    Zuo, Zhuang; Wu, Shubiao; Zhang, Wanqin; Dong, Renjie

    2014-06-01

    Vegetable waste, which characterized by high moisture content, was evaluated as a substrate for biogas production. The effects of recirculation rate (RR) on the performance of two-stage anaerobic digestion were investigated. The system was operated at an organic loading rate of 1.7 g VS/L/d with varying RRs (0, 0.6, 1, and 1.4). Results demonstrated that volumetric biogas production rates in acidogenic reactor increased from approximately 0.2 7 L/L/d to 0.97 L/L/d, when pH is increased from approximately 5.1 to 6.7. These indicate that recirculation of alkaline effluent from the methanogenic reactor helps create a favorable condition for biogas production in the acidogenic reactor. The decrease in chemical oxygen demand (COD) concentrations from approximately 21,000 mg/L to 6800 mg/L was also observed in the acidogenic reactor. This condition may be attributed to dilution under recirculation. The dynamics between hydrolysis and methanogenesis under recirculation indicated that mass transfer capacity between two-stage reactors improved.

  15. Confined turbulent swirling recirculating flow predictions. Ph.D. Thesis. Final Report

    NASA Technical Reports Server (NTRS)

    Abujelala, M. T.; Lilley, D. G.

    1985-01-01

    The capability and the accuracy of the STARPIC computer code in predicting confined turbulent swirling recirculating flows is presented. Inlet flow boundary conditions were demonstrated to be extremely important in simulating a flowfield via numerical calculations. The degree of swirl strength and expansion ratio have strong effects on the characteristics of swirling flow. In a nonswirling flow, a large corner recirculation zone exists in the flowfield with an expansion ratio greater than one. However, as the degree of inlet swirl increases, the size of this zone decreases and a central recirculation zone appears near the inlet. Generally, the size of the central zone increased with swirl strength and expansion ratio. Neither the standard k-epsilon turbulence mode nor its previous extensions show effective capability for predicting confined turbulent swirling recirculating flows. However, either reduced optimum values of three parameters in the mode or the empirical C sub mu formulation obtained via careful analysis of available turbulence measurements, can provide more acceptable accuracy in the prediction of these swirling flows.

  16. Geosmin causes off-flavour in arctic charr in recirculating aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The “earthy” and “muddy” off-flavors in pond-reared fish are due to the presence of geosmin or 2-methylisoborneol (MIB) in the flesh of the fish. Similar off-flavors have been reported in fish raised in recirculating aquaculture systems (RAS); however, little information is available regarding the ...

  17. Improvement of anaerobic digester performance by wastewater recirculation through an aerated membrane.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Swine wastewater from an anaerobic digester was recirculated through a silicone hose located in an external aeration chamber to determine its effect on wastewater malodorants and biogas composition. The silicone hose acted as a semipermeable membrane for the passage of small molecules. In the first...

  18. Researchers evaluate low-energy recirculating system for inland production of marine finfish juveniles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The low-energy recirculating aquaculture system consists of nine separate modules which utilize the double drain fish culture tank paired to a moving bed biofilter. The nine fiberglass tanks are five feet in diameter and normal water depth is about three feet for a total tank volume of approximately...

  19. Solids removal from a coldwater recirculating system - comparison of swirl separator and radial-flow settlers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Solids removal across two settling devices, i.e., a swirl separator and a radial-flow settler, and across a microscreen drum filter was evaluated in a fully recirculating system containing a single 150 m3 'Cornell-type' dual-drain tank during the production of food-size Arctic char and rainbow trout...

  20. Observations on side-swimming rainbow trout Oncorhynchus mykiss in water recirculation aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRAS), it was observed that rainbow trout Oncorhynchus mykiss in all WRAS exhibited a higher-than-normal prevalence of side-swimming (i.e. controlled, forward swimming, but with misaligned orientation suc...

  1. Building America Case Study: Control Retrofits for Multifamily Domestic Hot Water Recirculation Systems, Brooklyn, New York

    SciTech Connect

    2016-12-01

    Domestic hot water (DHW) heating is the second largest energy end use in U.S. buildings, exceeded only by space conditioning. Recirculation systems consisting of a pump and piping loop(s) are commonly used in multifamily buildings to reduce wait time for hot water at faucets; however, constant pumping increases energy consumption by exposing supply and return line piping to continuous heat loss, even during periods when there is no demand for hot water. In this study, ARIES installed and tested two types of recirculation controls in a pair of buildings in order to evaluate their energy savings potential. Demand control, temperature modulation controls, and the simultaneous operation of both were compared to the baseline case of constant recirculation. Additionally, interactive effects between DHW control fuel reductions and space conditioning (heating and cooling) were estimated in order to make more realistic predictions of the payback and financial viability of retrofitting DHW systems with these controls. Results showed that DHW fuel consumption reduced by 7 percent after implementing the demand control technique, 2 percent after implementing temperature modulation, and 15 percent after implementing demand control and temperature modulation techniques simultaneously; recirculation pump runtime was reduced to 14 minutes or less per day. With space heating and cooling interactions included, the estimated annual cost savings were 8 percent, 1 percent, and 14 percent for the respective control techniques. Possible complications in the installation, commissioning and operation of the controls were identified and solutions offered.

  2. CCR7 Controls Thymus Recirculation, but Not Production and Emigration, of Foxp3(+) T Cells.

    PubMed

    Cowan, Jennifer E; McCarthy, Nicholas I; Anderson, Graham

    2016-02-09

    Current models of Foxp3(+) regulatory T cell (Treg) development involve CCR7-mediated migration of thymocytes into the thymus medulla to enable essential interactions with medullary epithelium. However, increased Foxp3(+) thymic Treg numbers in Ccr7(-/-) mice challenge this view, and the role of CCR7 in Treg development, emigration, and/or recirculation is unknown. Here, we have examined CCR7 and Rag2pGFP levels during Treg development and generated Rag2pGFPCcr7(-/-) mice to study its impact on the intrathymic Treg pool. We reveal surprising developmental heterogeneity in thymocytes described as Treg precursors, showing that they contain recirculating CCR6(+)CCR7(-)Rag2pGFP(-) T cells. Although CCR7 defines bona fide Rag2GFP(+) Treg precursors, it is not required for Treg production and emigration. Rather, we show that lack of CCR7 renders the thymus more receptive to Treg thymus homing. Our study reveals a role for CCR7 in limiting Treg recirculation back to the thymus and enables separation of the mechanisms controlling Treg production and thymic recirculation.

  3. The benefits of powdered activated carbon recirculation for micropollutant removal in advanced wastewater treatment.

    PubMed

    Meinel, F; Zietzschmann, F; Ruhl, A S; Sperlich, A; Jekel, M

    2016-03-15

    PAC adsorption is a widespread option for the removal of organic micropollutants (OMP) from secondary effluent. For an optimal exploitation of the adsorption capacity, PAC recirculation is nowadays a common practice, although the mechanistic interrelations of the complex recirculation process are not fully resolved. In this work, extensive multi-stage batch adsorption testing with repeated PAC and coagulant dosage was performed to evaluate the continuous-flow recirculation system. Partly loaded PAC showed a distinct amount of remaining capacity, as OMP and DOC removals considerably increased with each additional adsorption stage. At a low PAC dose of 10 mg PAC L(-1), removals of benzotriazole and carbamazepine were shown to rise from <40% in the first stage up to >80% in the 11th stage at 30 min adsorption time per stage. At a high PAC dose of 30 mg PAC L(-1), OMP and DOC removals were significantly higher and reached 98% (for benzotriazole and carbamazepine) after 11 stages. Coagulant dosage showed no influence on OMP removal, whereas a major part of DOC removal can be attributed to coagulation. Multi-stage adsorption is particularly beneficial for small PAC doses and significant PAC savings are feasible. A new model approach for predicting multi-stage OMP adsorption on the basis of a single-stage adsorption experiment was developed. It proved to predict OMP removals and PAC loadings accurately and thus contributes towards understanding the PAC recirculation process.

  4. Low-head recirculating aquaculture system for juvenile red drum production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA Agricultural Research Service and the Center for Aquaculture and Stock Enhancement at Harbor Branch Oceanographic Institute-FAU (HBOI-FAU) are collaborating to evaluate low-head recirculating aquaculture system designs to intensively produce red drum juveniles as part of the Florida Fish an...

  5. Disinfection of water in recirculating aquaculture systems with peracetic acid (PAA)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The disinfection behaviour of peracetic acid (PAA) in recirculating aquaculture systems (RAS) was investigated. Peracetic acid is a strong oxidizing agent found in various concentrations in different products. Three Wofasteril PAA products (E400 (c), Lspecical; AC 150) were tested in vitro for the...

  6. Identifying built environmental patterns using cluster analysis and GIS: Relationships with walking, cycling and body mass index in French adults

    PubMed Central

    2012-01-01

    Background Socio-ecological models suggest that both individual and neighborhood characteristics contribute to facilitating health-enhancing behaviors such as physical activity. Few European studies have explored relationships between local built environmental characteristics, recreational walking and cycling and weight status in adults. The aim of this study was to identify built environmental patterns in a French urban context and to assess associations with recreational walking and cycling behaviors as performed by middle-aged adult residents. Methods We used a two-step procedure based on cluster analysis to identify built environmental patterns in the region surrounding Paris, France, using measures derived from Geographic Information Systems databases on green spaces, proximity facilities (destinations) and cycle paths. Individual data were obtained from participants in the SU.VI.MAX cohort; 1,309 participants residing in the Ile-de-France in 2007 were included in this analysis. Associations between built environment patterns, leisure walking/cycling data (h/week) and measured weight status were assessed using multinomial logistic regression with adjustment for individual and neighborhood characteristics. Results Based on accessibility to green spaces, proximity facilities and availability of cycle paths, seven built environmental patterns were identified. The geographic distribution of built environmental patterns in the Ile-de-France showed that a pattern characterized by poor spatial accessibility to green spaces and proximity facilities and an absence of cycle paths was found only in neighborhoods in the outer suburbs, whereas patterns characterized by better spatial accessibility to green spaces, proximity facilities and cycle paths were more evenly distributed across the region. Compared to the reference pattern (poor accessibility to green areas and facilities, absence of cycle paths), subjects residing in neighborhoods characterized by high

  7. Performance of Water Recirculation Loop Maintentance Components for the Advanced Spacesuit Water Membrane Evaporator

    NASA Technical Reports Server (NTRS)

    Rector, Tony; Peyton, Barbara; Steele, John W.; Bue, Grant C.; Campbell, Colin; Makinen, Janice

    2014-01-01

    Water loop maintenance components to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop have undergone a comparative performance evaluation with a second SWME water recirculation loop with no water quality maintenance. Results show the benefits of periodic water maintenance. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the evaluation of water recirculation maintenance components was to further enhance this advantage through the leveraging of fluid loop management lessonslearned from the International Space Station (ISS). A bed design that was developed for a UTAS military application, and considered for a potential ISS application with the Urine Processor Assembly, provided a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance cycle included the use of a biocide delivery component developed for ISS to introduce a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.

  8. Performance of Water Recirculation Loop Maintenance Components for the Advanced Spacesuit Water Membrane Evaporator

    NASA Technical Reports Server (NTRS)

    Rector, Tony; Peyton, Barbara M.; Steele, John W.; Makinen, Janice; Bue, Grant C.; Campbell, Colin

    2014-01-01

    Water loop maintenance components to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop have undergone a comparative performance evaluation with a second SWME water recirculation loop with no water quality maintenance. Results show the benefits of periodic water maintenance. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the evaluation of water recirculation maintenance components was to further enhance this advantage through the leveraging of fluid loop management lessons learned from the International Space Station (ISS). A bed design that was developed for a UTAS military application, and considered for a potential ISS application with the Urine Processor Assembly, provided a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance cycle included the use of a biocide delivery component developed for ISS to introduce a biocide in a microgravity compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.

  9. Full-scale leachate-recirculating MSW landfill bioreactor assessments

    SciTech Connect

    Carson, D.A.

    1995-10-01

    The integrated waste management hierarchy philosophy continues to develop as a useful tool to solve solid waste issues in an environmentally responsible manner. Recent statistics indicate that approximately two thirds of municipal solid waste in the United States is disposed in landfills. Current landfill operational technique involves the preparation of a waste containment facility, the filling of the waste unit, installation of the final cover, and the maintenance of the unit. This method of operation has proven to be reasonably effective in waste disposal, effectively minimizing risk by collecting the liquid that percolates through the waste, called leachates, at the bottom of the landfill, and controlling landfill gas with collection systems. Concerns over the longevity of containment systems components present questions that cannot be answered without substantial performance data. Landfills, as currently operated, serve to entomb dry waste. Therefore, the facility must be maintained in perpetuity, consuming funds and ultimately driving up waste collection costs. This presentation will describe a new form of solid waste landfill operation, it is a technique that involves controlled natural processes to break down landfilled waste, and further minimize risk to human health and the environment. A landfill operated in an active manner will encourage and control natural decomposition of landfilled waste. This can be accomplished by collecting leachate, and reinjecting it into the landfilled waste mass. Keeping the waste mass moist will lead to a largely anaerobic system with the capacity to rapidly stabilize the landfilled waste mass via physical, chemical and biological methods. The system has proven the ability to breakdown portions of the waste mass, and to degrade toxic materials at the laboratory scale.

  10. Understanding the independent and joint associations of the home and workplace built environments on cardiorespiratory fitness and body mass index.

    PubMed

    Hoehner, Christine M; Allen, Peg; Barlow, Carolyn E; Marx, Christine M; Brownson, Ross C; Schootman, Mario

    2013-10-01

    This observational study examined the associations of built environment features around the home and workplace with cardiorespiratory fitness (CRF) based on a treadmill test and body mass index (BMI) (weight (kg)/height (m)(2)). The study included 8,857 adults aged 20-88 years who completed a preventive medical examination in 2000-2007 while living in 12 Texas counties. Analyses examining workplace neighborhood characteristics included a subset of 4,734 participants. Built environment variables were derived around addresses by using geographic information systems. Models were adjusted for individual-level and census block group-level demographics and socioeconomic status, smoking, BMI (in CRF models), and all other home or workplace built environment variables. CRF was associated with higher intersection density, higher number of private exercise facilities around the home and workplace, larger area of vegetation around the home, and shorter distance to the closest city center. Aside from vegetation, these same built environment features around the home were also associated with BMI. Participants who lived and worked in neighborhoods in the lowest tertiles for intersection density and the number of private exercise facilities had lower CRF and higher BMI values than participants who lived and worked in higher tertiles for these variables. This study contributes new evidence to suggest that built environment features around homes and workplaces may affect health.

  11. The Use of Exhaust Gas Recirculation to Optimize Fuel Economy and Minimize Emission in Engines Operating on E85 Fuel

    SciTech Connect

    Wu, Ko-Jen

    2011-12-31

    This report summarizes activities conducted for the project “The Use of Exhaust Gas Recirculation to Optimized Fuel Economy and Minimize Emissions in Engines Operating on E85 Fuel” under COOPERATIVE AGREEMENT NUMBER DE-FC26-07NT43271, which are as outlined in the STATEMENT OF PROJECT OBJECTIVES (SOPO) dated March 2007 and in the supplemental SOPO dated October 2010. The project objective was to develop and demonstrate an internal combustion engine that is optimized for E85 (85% ethanol and 15% gasoline) fuel operation to achieve substantially improved fuel economy while operating with E85 fuel and that is also production viable in the near- to medium-term. The key engine technology selected for research and development was turbocharging, which is known to improve fuel economy thru downsizing and is in particular capable of exploiting ethanol fuel’s characteristics of high octane number and high latent heat of vaporization. The engine further integrated synergistic efficiency improving technologies of cooled exhaust gas recirculation (EGR), direct fuel injection and dual continuously variable intake and exhaust cam phasers. On the vehicle level, fuel economy was furthered thru powertrain system optimization by mating a state-of-the-art six-speed automatic transmission to the engine. In order to achieve the project’s objective of near- to medium-term production viability, it was essential to develop the engine to be flex-fuel capable of operating with fuels ranging from E0 (0% ethanol and 100% gasoline) to E85 and to use three-way type of catalyst technology for exhaust aftertreatment. Within these scopes, various technologies were developed through systems approach to focus on ways to help accelerate catalyst light-off. Significant amount of development took place during the course of the project within General Motors, LLC. Many prototype flex-fuel engines were designed, built and developed with various hardware configurations selected to achieve the project

  12. Measuring the built environment for physical activity: state of the science.

    PubMed

    Brownson, Ross C; Hoehner, Christine M; Day, Kristen; Forsyth, Ann; Sallis, James F

    2009-04-01

    Physical inactivity is one of the most important public health issues in the U.S. and internationally. Increasingly, links are being identified between various elements of the physical-or built-environment and physical activity. To understand the impact of the built environment on physical activity, the development of high-quality measures is essential. Three categories of built environment data are being used: (1) perceived measures obtained by telephone interview or self-administered questionnaires; (2) observational measures obtained using systematic observational methods (audits); and (3) archival data sets that are often layered and analyzed with GIS. This review provides a critical assessment of these three types of built-environment measures relevant to the study of physical activity. Among perceived measures, 19 questionnaires were reviewed, ranging in length from 7 to 68 questions. Twenty audit tools were reviewed that cover community environments (i.e., neighborhoods, cities), parks, and trails. For GIS-derived measures, more than 50 studies were reviewed. A large degree of variability was found in the operationalization of common GIS measures, which include population density, land-use mix, access to recreational facilities, and street pattern. This first comprehensive examination of built-environment measures demonstrates considerable progress over the past decade, showing diverse environmental variables available that use multiple modes of assessment. Most can be considered first-generation measures, so further development is needed. In particular, further research is needed to improve the technical quality of measures, understand the relevance to various population groups, and understand the utility of measures for science and public health.

  13. Built Environment and Elderly Population Health: A Comprehensive Literature Review

    PubMed Central

    Garin, Noe; Olaya, Beatriz; Miret, Marta; Ayuso-Mateos, Jose Luis; Power, Michael; Bucciarelli, Paola; Haro, Josep Maria

    2014-01-01

    Global population aging over recent years has been linked to poorer health outcomes and higher healthcare expenditure. Policies focusing on healthy aging are currently being developed but a complete understanding of health determinants is needed to guide these efforts. The built environment and other external factors have been added to the International Classification of Functioning as important determinants of health and disability. Although the relationship between the built environment and health has been widely examined in working age adults, research focusing on elderly people is relatively recent. In this review, we provide a comprehensive synthesis of the evidence on the built environment and health in the elderly. PMID:25356084

  14. Effect of self recirculation casing treatment on the performance of a turbocharger centrifugal compressor

    NASA Astrophysics Data System (ADS)

    Gancedo, Matthieu

    Increase in emission regulations in the transport industry brings the need to have more efficient engines. A path followed by the automobile industry is to downsize the size of the internal combustion engine and increase the air density at the intake to keep the engine power when needed. Typically a centrifugal compressor is used to force the air into the engine, it can be powered from the engine shaft (superchargers) or extracting energy contained into the hot exhaust gases with a turbine (turbochargers). The flow range of the compressor needs to match the one of the engine. However compressors mass flow operating range is limited by choke on the high end and surge on the low end. In order to extend the operation at low mass flow rates, the use of passive devices for turbocharger centrifugal compressors was explored since the late 80's. Hence, casing treatments including flow recirculation from the inducer part of the compressor have been shown to move the surge limit to lower flows. Yet, the working mechanisms are still not well understood and thus, to optimize the design of this by-pass system, it is necessary to determine the nature of the changes induced by the device both on the dynamic stability of the pressure delivery and on the flow at the inlet. The compressor studied here features a self-recirculating casing treatment at the inlet. The recirculation passage could be blocked to carry a direct comparison between the cases with and without the flow feature. To grasp the effect on compressor stability, pressure measurements were taken in the different constituting elements of the compressor. The study of the mean pressure variations across the operating map showed that the tongue region is a limiting element. Dynamic pressure measurements revealed that the instabilities generated near the inducer when the recirculation is blocked increase the overall instability levels at the compressor outlet and propagating pressure waves starting at the tongue occurred

  15. View northwest, discharge basin, floor, showing cement cross beams built ...

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

    View northwest, discharge basin, floor, showing cement cross beams built on stone bases - Glens Falls Feeder, Sluice, Along south side of Glens Falls Feeder between locks 10 & 20, Hudson Falls, Washington County, NY

  16. United Space Alliance, LLC Windchill As-Built Highlights

    NASA Technical Reports Server (NTRS)

    Richmond, Dena M.

    2011-01-01

    Work Order execution data from Solumina As Worked BOM (As-Built) in Solumina (Slide 2) sent to Windchill Windchill receives As Worked BOM data and 'marries' the Solumina execution data to the Part Instance/Product Structure/As-Design (Slide 3 As-Design and Slide 4 &5 As-Built) Manage the As-Built to As-Design delta's via the interface and Part Instance Attributes (Slide 6) including Work Order data and any CMcomments Produce an As-Built to As-Design report that also includes all Part Instance Attribute data (no screenshot as this is still in development) Utilize Windchill and Solumina 'Out of the Box' functionality

  17. VIEW OF FORMER WINDBER ELECTRIC COMPANY BUILDING, BUILT 1925, LOOKING ...

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

    VIEW OF FORMER WINDBER ELECTRIC COMPANY BUILDING, BUILT 1925, LOOKING NORTH, LOCATED ON THE NORTH SIDE OF 15TH STREET, NOW BERWIND-WILMORE DIVISION OFFICES AND REITZ COAL COMPANY - Windber Electric Building, 509 Fifteenth Street, Windber, Somerset County, PA

  18. 4. J. E. HERMAN HOUSE, built 1899, of SOFT CLAYLIKE ...

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

    4. J. E. HERMAN HOUSE, built 1899, of SOFT CLAY-LIKE MATERIAL THAT WAS QUARRIED AND THEN HARDENED ON CONTACT WITH AIR AND SUNSHINE. IT HAS NO DOORWAY TO STREET. - Town of Liebenthal, Liebenthal, Rush County, KS

  19. 26. INTERIOR VIEW SHOWING ROW OF TIMBER SUPPORT TOWERS BUILT ...

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

    26. INTERIOR VIEW SHOWING ROW OF TIMBER SUPPORT TOWERS BUILT AS TEMPORARY TRUSS REINFORCEMENT (NOTE STEEL STRUCTURES ATOP TIMBER BRACING) - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  20. 41. After steering hydraulic mechanism from starboard side. Mechanism built ...

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

    41. After steering hydraulic mechanism from starboard side. Mechanism built by the Superior Iron Works Co., Elizabeth, New Jersey, Lidgerwood Mfg Co. - U.S. Coast Guard Cutter BRAMBLE, Waterfront at Lincoln Avenue, Port Huron, St. Clair County, MI

  1. Main elevation of Lincoln School (built 1928) utilized by the ...

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

    Main elevation of Lincoln School (built 1928) utilized by the children of Lincoln Mill workers living the surrounding mill housing neighborhood - Lincoln School, 1110 Meridian Street, Huntsville, Madison County, AL

  2. 7. VIEW OF GEAR SHAPER. Built 1935 (Conrail 00015). Fellows ...

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

    7. VIEW OF GEAR SHAPER. Built 1935 (Conrail 00015). Fellows Gear Shaper Company, Springfield, Vermont. - Juniata Shops, Machine Shop No. 1, East of Fourth Avenue at Third Street, Altoona, Blair County, PA

  3. DETAIL VIEW OF BATCH CAR, BUILT BY ATLAS CAR & ...

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

    DETAIL VIEW OF BATCH CAR, BUILT BY ATLAS CAR & MANUFACTURING COMPANY. BATCH STORAGE SILOS IN BACKGROUND - Chambers Window Glass Company, Batch Plant, North of Drey (Nineteenth) Street, West of Constitution Boulevard, Arnold, Westmoreland County, PA

  4. 2. Conveyor 'N' (built ca. 1950) north of Station and ...

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

    2. Conveyor 'N' (built ca. 1950) north of Station and connecting to South Street Station, looking northeast. - Manchester Street Generating Station, Conveyors, 460 Eddy Street, Providence, Providence County, RI

  5. Impact of nitrate-enhanced leachate recirculation on gaseous releases from a landfill bioreactor cell

    SciTech Connect

    Tallec, G.; Bureau, C.; Peu, P.; Benoist, J.C.; Lemunier, M.; Budka, A.; Presse, D.; Bouchez, T.

    2009-07-15

    This study evaluates the impact of nitrate injection on a full scale landfill bioreactor through the monitoring of gaseous releases and particularly N{sub 2}O emissions. During several weeks, we monitored gas concentrations in the landfill gas collection system as well as surface gas releases with a series of seven static chambers. These devices were directly connected to a gas chromatograph coupled to a flame ionisation detector and an electron capture detector (GC-FID/ECD) placed directly on the field. Measurements were performed before, during and after recirculation of raw leachate and nitrate-enhanced leachate. Raw leachate recirculation did not have a significant effect on the biogas concentrations (CO{sub 2}, CH{sub 4} and N{sub 2}O) in the gas extraction network. However, nitrate-enhanced leachate recirculation induced a marked increase of the N{sub 2}O concentrations in the gas collected from the recirculation trench (100-fold increase from 0.2 ppm to 23 ppm). In the common gas collection system however, this N{sub 2}O increase was no more detectable because of dilution by gas coming from other cells or ambient air intrusion. Surface releases through the temporary cover were characterized by a large spatial and temporal variability. One automated chamber gave limited standard errors over each experimental period for N{sub 2}O releases: 8.1 {+-} 0.16 mg m{sup -2} d{sup -1} (n = 384), 4.2 {+-} 0.14 mg m{sup -2} d{sup -1} (n = 132) and 1.9 {+-} 0.10 mg m{sup -2} d{sup -1} (n = 49), during, after raw leachate and nitrate-enhanced leachate recirculation, respectively. No clear correlation between N{sub 2}O gaseous surface releases and recirculation events were evidenced. Estimated N{sub 2}O fluxes remained in the lower range of what is reported in the literature for landfill covers, even after nitrate injection.

  6. Results of initial operation of the Jupiter Oxygen Corporation oxy-fuel 15 MWth burner test facility

    SciTech Connect

    Thomas Ochs, Danylo Oryshchyn, Rigel Woodside, Cathy Summers, Brian Patrick, Dietrich Gross, Mark Schoenfield, Thomas Weber and Dan O'Brien

    2009-04-01

    Jupiter Oxygen Corporation (JOC), in cooperation with the National Energy Technology Laboratory (NETL), constructed a 15 MWth oxy-fuel burner test facility with Integrated Pollutant Removal (IPRTM) to test high flame temperature oxy-fuel combustion and advanced carbon capture. Combustion protocols include baseline air firing with natural gas, oxygen and natural gas firing with and without flue gas recirculation, and oxygen and pulverized coal firing with flue gas recirculation. Testing focuses on characterizing burner performance, determining heat transfer characteristics, optimizing CO2 capture, and maximizing heat recovery, with an emphasis on data traceability to address retrofit of existing boilers by directly transforming burner systems to oxy-fuel firing.

  7. Expert Meeting Report: Advanced Envelope Research for Factory Built Housing

    SciTech Connect

    Levy, E.; Mullens, M.; Tompos, E.; Kessler, B.; Rath, P.

    2012-04-01

    This report provides information about the expert meeting on advanced envelope research for factory built housing, hosted by the ARIES Collaborative on October 11, 2011, in Phoenix, Arizona. The goals of this meeting were to provide a comprehensive solution to the use of three previously selected advanced alternatives for factory-built wall construction, assess each option focusing on major issues relating to viability and commercial potential, and determine additional steps are required to reach this potential.

  8. Expert Meeting Report: Advanced Envelope Research for Factory Built Housing

    SciTech Connect

    Levy, E.; Mullens, M.; Tompos, E.; Kessler, B.; Rath, P.

    2012-04-01

    This report provides information about the Building America expert meeting on advanced envelope research for factory built housing, hosted by the ARIES Collaborative on October 11, 2011, in Phoenix, Arizona. The goals of this meeting were to provide a comprehensive solution to the use of three previously selected advanced alternatives for factory-built wall construction, assess each option focusing on major issues relating to viability and commercial potential, and determine additional steps are required to reach this potential.

  9. 55. Virginia Route 688 grade separation structure. This structure, built ...

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

    55. Virginia Route 688 grade separation structure. This structure, built in 1960, is an example of several concrete box culverts built primarily in the late 1950's and early 1960's. They are simply plain concrete with now ornamentation. These structures were used only on lesser used secondary paved roads or dirt roads. View is looking south. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  10. Healthy Toronto by Design: Promoting a healthier built environment.

    PubMed

    Macfarlane, Ronald G; Wood, Linda P; Campbell, Monica E

    2014-07-08

    Chronic diseases, obesity and sedentary lifestyles are some of the health challenges facing Canada today. There is increasing recognition and evidence that the way our cities are planned, designed and built can contribute to these problems. Many of the policy levers to address the built environment exist outside the health sector and at the municipal level in areas such as urban planning, transportation, parks and recreation, and housing. The challenge for the public health sector is to build and sustain partnerships and collaboration across various sectors to ensure that health is considered in built environment policies. As the public health unit for the city of Toronto and part of the municipal government, Toronto Public Health is in a unique position to provide leadership, advocacy and support for healthy municipal public policies related to the built environment. This article provides some examples of CLASP (Coalitions Linking Action and Science for Prevention) initiatives undertaken to help create support for healthy public policies in the built environment and suggests that the "Healthy Cities" approach is a useful framework to promote policy change in the built environment at the municipal level.

  11. Facility Planning.

    ERIC Educational Resources Information Center

    Graves, Ben E.

    1984-01-01

    This article reviews recommendations on policies for leasing surplus school space made during the Council of Educational Facility Planners/International conference. A case study presentation of a Seattle district's use of lease agreements is summarized. (MJL)

  12. NASA Langley Low Speed Aeroacoustic Wind Tunnel: Background Noise and Flow Survey Results Prior to FY05 Construction of Facilities Modifications

    NASA Technical Reports Server (NTRS)

    Booth, Earl R., Jr.; Henderson, Brenda S.

    2005-01-01

    The NASA Langley Research Center Low Speed Aeroacoustic Wind Tunnel is a premier facility for model-scale testing of jet noise reduction concepts at realistic flow conditions. However, flow inside the open jet test section is less than optimum. A Construction of Facilities project, scheduled for FY 05, will replace the flow collector with a new design intended to reduce recirculation in the open jet test section. The reduction of recirculation will reduce background noise levels measured by a microphone array impinged by the recirculation flow and will improve flow characteristics in the open jet tunnel flow. In order to assess the degree to which this modification is successful, background noise levels and tunnel flow are documented, in order to establish a baseline, in this report.

  13. A novel tool for assessing and summarizing the built environment

    PubMed Central

    2012-01-01

    Background A growing corpus of research focuses on assessing the quality of the local built environment and also examining the relationship between the built environment and health outcomes and indicators in communities. However, there is a lack of research presenting a highly resolved, systematic, and comprehensive spatial approach to assessing the built environment over a large geographic extent. In this paper, we contribute to the built environment literature by describing a tool used to assess the residential built environment at the tax parcel-level, as well as a methodology for summarizing the data into meaningful indices for linkages with health data. Methods A database containing residential built environment variables was constructed using the existing body of literature, as well as input from local community partners. During the summer of 2008, a team of trained assessors conducted an on-foot, curb-side assessment of approximately 17,000 tax parcels in Durham, North Carolina, evaluating the built environment on over 80 variables using handheld Global Positioning System (GPS) devices. The exercise was repeated again in the summer of 2011 over a larger geographic area that included roughly 30,700 tax parcels; summary data presented here are from the 2008 assessment. Results Built environment data were combined with Durham crime data and tax assessor data in order to construct seven built environment indices. These indices were aggregated to US Census blocks, as well as to primary adjacency communities (PACs) and secondary adjacency communities (SACs) which better described the larger neighborhood context experienced by local residents. Results were disseminated to community members, public health professionals, and government officials. Conclusions The assessment tool described is both easily-replicable and comprehensive in design. Furthermore, our construction of PACs and SACs introduces a novel concept to approximate varying scales of community and

  14. LUX - A recirculating linac-based ultrafast X-ray source

    SciTech Connect

    Corlett, J.N.; Barletta, W.A.; DeSantis, S.; Doolittle, L.; Fawley, W.M.; Green, M.A.; Heimann, P.; Leone, S.R.; Lidia, S.; Li, D.; Parmigiani, F.; Ratti, A.; Robinson, K.; Schoenlein, R.; Staples, J.; Wan, W.; Wells, R.; Wilcox, R.; Wolski, A.; Zholents, A.

    2003-08-01

    We describe the design of a proposed source of ultra-fast synchrotron radiation x-ray pulses based on a recirculating superconducting linac, with an integrated array of ultrafast laser systems. The source produces x-ray pulses with duration of 10-50 fs at a 10 kHz repetition rate, with tunability from EUV to hard x-ray regimes, and optimized for the study of ultra-fast dynamics. A high-brightness rf photocathode provides electron bunches. An injector linac accelerates the beam to the 100 MeV range, and is followed by four passes through a 700 MeV recirculating linac. Ultrafast hard x-ray pulses are obtained by a combination of electron bunch manipulation, transverse temporal correlation of the electrons, and x-ray pulse compression. EUV and soft x-ray pulses as short as 10 fs are generated in a harmonic-cascade free electron laser scheme.

  15. Peripheral regulatory T lymphocytes recirculating to the thymus suppress the development of their precursors.

    PubMed

    Thiault, Nicolas; Darrigues, Julie; Adoue, Véronique; Gros, Marine; Binet, Bénédicte; Perals, Corine; Leobon, Bertrand; Fazilleau, Nicolas; Joffre, Olivier P; Robey, Ellen A; van Meerwijk, Joost P M; Romagnoli, Paola

    2015-06-01

    Most T lymphocytes, including regulatory T cells (Treg cells), differentiate in the thymus. The age-dependent involution of this organ leads to decreasing production of T cells. Here we found that the output of new Treg cells from the thymus decreased substantially more than that of conventional T cells. Peripheral mouse and human Treg cells recirculated back to the thymus, where they constituted a large proportion of the pool of Treg cells and displayed an activated and differentiated phenotype. In the thymus, the recirculating cells exerted their regulatory function by inhibiting interleukin 2 (IL-2)-dependent de novo differentiation of Treg cells. Thus, Treg cell development is controlled by a negative feedback loop in which mature progeny cells return to the thymus and restrain development of precursors of Treg cells.

  16. Manipulating flow separation: sensitivity of stagnation points, separatrix angles and recirculation area to steady actuation

    PubMed Central

    Boujo, E.; Gallaire, F.

    2014-01-01

    A variational technique is used to derive analytical expressions for the sensitivity of several geometric indicators of flow separation to steady actuation. Considering the boundary layer flow above a wall-mounted bump, the six following representative quantities are considered: the locations of the separation point and reattachment point connected by the separatrix, the separation angles at these stagnation points, the backflow area and the recirculation area. For each geometric quantity, linear sensitivity analysis allows us to identify regions which are the most sensitive to volume forcing and wall blowing/suction. Validations against full nonlinear Navier−Stokes calculations show excellent agreement for small-amplitude control for all considered indicators. With very resemblant sensitivity maps, the reattachment point, the backflow and recirculation areas are seen to be easily manipulated. By contrast, the upstream separation point and the separatrix angles are seen to remain extremely robust with respect to external steady actuation. PMID:25294968

  17. Removal of sodium chloride from human urine via batch recirculation electrodialysis at constant applied voltage

    NASA Technical Reports Server (NTRS)

    Gordils-Striker, Nilda E.; Colon, Guillermo

    2003-01-01

    The removal of sodium chloride (NaCl) from human urine using a six-compartment electrodialysis cell with batch recirculation mode of operation for use in advanced life support systems (ALSS) was studied. From the results obtained, batch recirculation at constant applied voltage yields high values (approximately 94% of NaCl removal. Based on the results, the initial rate of NaCl removal was correlated to a power function of the applied voltage: -r=2.0 x 10(-4)E(3.8). With impedance spectroscopy methods, it was also found that the anion membranes were more affected by fouling with an increase of the ohmic resistance of almost 11% compared with 7.4% for the cationic ones.

  18. Computational fluid dynamics analysis of external recirculation flow at updraft gasifier using ejector

    NASA Astrophysics Data System (ADS)

    Vidiana, Fajri; Surjosatyo, Adi; Nugroho, Yulianto Sulistyo

    2012-06-01

    Gasification process at updraft gasifier produces the amount of more tar than the other gasifier type. To reduce tar at updraft gasifier, it is carried out recirculation of pirolysis gas into combustion zone. Ejector is an equipment used to entrain the secondary fluid flow by moving momentum and energy from high velocity of primary flow (jet). Research carries out the simulation of isothermal 3D using Computational Fluid Dynamics (CFD) to obtain the maximum of recirculation flow at updraft gasifier using ejector. The result of simulation shows that change of nozzle diameter gives great influence at change of total flow for resirculation compared with the change of diameter and length of mixing area and nozzle exit position (NXP). The maximum of resirculation flow 81 lpm at nozzle diameter 0.75 cm.

  19. CFB combustor with internal solids recirculation -- Pilot testing and design applications

    SciTech Connect

    Belin, F.; Maryamchik, M.; Fuller, T.A.; Perna, M.A.

    1995-12-31

    The new generation of B and W`s CFB boilers with entirely internal recirculation of solids collected by the primary impact separator is uniquely compact and features a simple, low-maintenance solids collection system. Thorough testing of the new concept at the Cold CFB Model and the 2.5 MWth Pilot CFB combustor confirmed its effective performance equal to that of a CFB unit with external solids recirculation from the primary separator. While providing overall advantages of compactness and simplicity, the new design is especially valuable for repowering of the existing power plants where B and W`s CFB boiler fits into the plan area of PC-fired boilers.

  20. Thermal characterization of an AMTEC recirculating test cell. [Alkali Metal ThermoElectric Converter

    NASA Technical Reports Server (NTRS)

    Underwood, M. L.; O'Connor, D.; Williams, R. M.; Jeffries-Nakamura, B.; Ryan, M. A.; Bankston, C. P.

    1990-01-01

    An alkali metal thermoelectric converter (AMTEC) recirculating test cell has been operated in order to determine the magnitudes of the primary heat losses of the cell and the value of the emissivity of the condenser surface. The energy balance included radiation losses, conductive losses, and losses due to the flow of sodium into the cell. The radiative heat flux dominated the heat loss mechanism of the cell at open circuit, and the condenser emissivity was calculated to be about 0.1. It is shown that, if this emissivity can be reduced to 0.02, then parasitic losses in an AMTEC recirculating test cell operating near peak power would be less than 40 percent of the heat required by the cell. The condenser emissivity decreases with elapsed time, resulting in improved thermal performance of the cell.

  1. Manipulating flow separation: sensitivity of stagnation points, separatrix angles and recirculation area to steady actuation.

    PubMed

    Boujo, E; Gallaire, F

    2014-10-08

    A variational technique is used to derive analytical expressions for the sensitivity of several geometric indicators of flow separation to steady actuation. Considering the boundary layer flow above a wall-mounted bump, the six following representative quantities are considered: the locations of the separation point and reattachment point connected by the separatrix, the separation angles at these stagnation points, the backflow area and the recirculation area. For each geometric quantity, linear sensitivity analysis allows us to identify regions which are the most sensitive to volume forcing and wall blowing/suction. Validations against full nonlinear Navier-Stokes calculations show excellent agreement for small-amplitude control for all considered indicators. With very resemblant sensitivity maps, the reattachment point, the backflow and recirculation areas are seen to be easily manipulated. By contrast, the upstream separation point and the separatrix angles are seen to remain extremely robust with respect to external steady actuation.

  2. Hexachlorobenzene uptake by fathead minnows and macroinvertebrates in recirculating sediment/water systems

    SciTech Connect

    Schuytema, G.S.; Krawczyk, D.F.; Griffis, W.L.; Nebeker, A.V.; Robideaux, M.L.

    1990-01-01

    Fathead minnow (Pimephales promelas), the worm, Lumbriculus variegatus, and the amphipods Hyalella azteca and Gammarus lacustris were exposed to hexachlorobenzene (HCB) in water with and without a bed of HCB-spiked sediment. Water HCB concentrations were maintained by recirculation through HCB-packed columns. Recirculating HCB-bound particulates and possibly eroded HCB particulates were an added source of HCB in addition to the sediment bed. Significant bioaccumulation of HCB in animal tissues was observed in water-only and water-sediment exposures. The presence of the HCB-spiked sediment did not result in a significant increase in the uptake of HCB by the organisms, but there was a substantial increase in sediment HCB levels over time. Higher tissue HCB levels in aquaria without sediment suggest that the sediment was a more efficient sink for HCB than the organisms.

  3. Effect of enhanced leachate recirculated (ELR) landfill operation and gas extraction on greenhouse gas emissions

    NASA Astrophysics Data System (ADS)

    Samir, Sonia

    The bioreactor/ enhanced leachate recirculated (ELR) landfill operation with the addition of moisture/ leachate to the landfill, accelerate the process of landfill waste decomposition; and increase the generation of LFG over a shorter period of time. Since emissions from the landfills are directly related to the gas generation, the increase in gas generation might also increase the emission from the landfill. On the contrary, the presence of gas extraction is suggested to mitigate the fugitive emissions from the landfills. Therefore, the motivation of the current study was to evaluate the effect of ELR operation as well as the gas extraction on the greenhouse gas emissions from the landfill. The current study was conducted in the City of Denton Landfill, Texas. Methane emission was investigated using a portable FID and static flux chamber technique from the landfill surface. Emission was measured from an ELR operated cell (cell 2) as well as a conventional cell (cell 0) in the City of Denton Landfill. Methane emission for cell 2 varied from 9544.3 ppm to 0 ppm while for cell 0, it varied from 0 ppm to 47 ppm. High spatial variations were observed during monitoring from both cells 0 and cell 2 which could be recognized as the variation of gas generation below the cover soil. The comparison between emissions from the slope and surface of the landfill showed that more methane emission occurred from the slopes than the top surface. In addition, the average landfill emission showed an increasing trend with increase in temperature and decreasing trend with increasing precipitation. The effect of ELR operation near the recirculation pipes showed a lag period between the recirculation and the maximum emission near the pipe. The emission near the pipe decreased after 1 day of recirculation and after the initial decrease, the emission started to increase and continued to increase up to 7 days after the recirculation. However, approximately after 10 days of recirculation, the

  4. Design and performance characteristics of a low-head recirculating aquaculture tank system for low salinity finfish production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water treatment components of a recirculating aquaculture system (RAS) consist mainly of: solid removal devices, biofiltration, aeration, degassing units, and water distribution. For each component, multiple options are available and the selection is based on system volume, system hydrodynamics, fis...

  5. Evaluation of leachate recirculation on nitrous oxide production in the Likang Landfill, China.

    PubMed

    Lee, Chun Man; Lin, Xue Rui; Lan, Chong Yu; Lo, Samuel Chun Lap; Chan, Gilbert Yuk Sing

    2002-01-01

    Landfill leachate recirculation is efficient in reducing the leachate quantity handled by a leachate treatment plant. However, after land application of leachate, nitrification and denitrification of the ammoniacal N becomes possible and the greenhouse gas nitrous oxide (N2O) is produced. Lack of information on the effects of leachate recirculation on N2O production led to a field study being conducted in the Likang Landfill (Guangzhou, China) where leachate recirculation had been practiced for 8 yr. Monthly productions and fluxes of N2O from leachate and soil were studied from June to November 2000. Environmental and chemical factors regulating N2O production were also accessed. An impermeable top liner was not used at this site; municipal solid waste was simply covered by inert soil and compacted by bulldozers. A high N2O emission rate (113 mg m-2 h-1) was detected from a leachate pond purposely formed on topsoil within the landfill boundary after leachate irrigation. A high N2O level (1.09 micrograms L-1) was detected in a gas sample emitted from topsoil 1 m from the leachate pond. Nitrous oxide production from denitrification in leachate-contaminated soil was at least 20 times higher than that from nitrification based on laboratory incubation studies. The N2O levels emitted from leachate ponds were compared with figures reported for different ecosystems and showed that the results of the present study were 68.7 to 88.6 times higher. Leachate recirculation can be a cost-effective operation in reducing the volume of leachate to be treated in landfill. However, to reduce N2O flux, leachate should be applied to underground soil rather than being irrigated and allowed to flow on topsoil.

  6. Evaluating leachate recirculation with cellulase addition to enhance waste biostabilisation and landfill gas production.

    PubMed

    Frank, R R; Davies, S; Wagland, S T; Villa, R; Trois, C; Coulon, F

    2016-09-01

    The effect of leachate recirculation with cellulase augmentation on municipal solid waste (MSW) biostabilisation and landfill gas production was investigated using batch bioreactors to determine the optimal conditions of moisture content, temperature and nutrients. Experimentation was thereafter scaled-up in 7L bioreactors. Three conditions were tested including (1) leachate recirculation only, (2) leachate recirculation with enzyme augmentation and (3) no leachate recirculation (control). Cumulative biogas production of the batch tests indicated that there was little difference between the leachate and control test conditions, producing on average 0.043m(3)biogaskg(-1) waste. However the addition of cellulase at 15×10(6)Utonne(-1) waste doubled the biogas production (0.074m(3)biogaskg(-1) waste). Similar trend was observed with the bioreactors. Cellulase addition also resulted in the highest COD reduction in both the waste and the leachate samples (47% and 42% COD reduction, respectively). In both cases, the quantity of biogas produced was closer to the lower value of theoretical and data-based biogas prediction indicators (0.05-0.4m(3)biogaskg(-1) waste). This was likely due to a high concentration of heavy metals present in the leachate, in particular Cr and Mn, which are known to be toxic to methanogens. The cost-benefit analysis (CBA) based on the settings of the study (cellulase concentration of 15×10(6)Utonne(-1) waste) showed that leachate bioaugmentation using cellulase is economically viable, with a net benefit of approximately €12.1million on a 5Mt mixed waste landfill.

  7. Conditions for coherent-synchrotron-radiation-induced microbunching suppression in multibend beam transport or recirculation arcs

    NASA Astrophysics Data System (ADS)

    Tsai, C.-Y.; Di Mitri, S.; Douglas, D.; Li, R.; Tennant, C.

    2017-02-01

    The coherent synchrotron radiation (CSR) of a high-brightness electron beam traversing a series of dipoles, such as transport or recirculation arcs, may result in beam phase space degradation. On one hand, CSR can perturb electron transverse motion in dispersive regions along the beam line and possibly cause emittance growth. On the other hand, the CSR effect on the longitudinal beam dynamics could result in microbunching instability. For transport arcs, several schemes have been proposed to suppress the CSR-induced emittance growth. Correspondingly, a few scenarios have been introduced to suppress CSR-induced microbunching instability, which however mostly aim for linac-based machines. In this paper we provide sufficient conditions for suppression of CSR-induced microbunching instability along transport or recirculation arcs. Examples are presented with the relevant microbunching analyses carried out by our developed semianalytical Vlasov solver [C.-Y. Tsai, D. Douglas, R. Li, and C. Tennant, Linear microbunching analysis for recirculation machines, Phys. Rev. ST Accel. Beams 19, 114401 (2016), 10.1103/PhysRevAccelBeams.19.114401]. The example lattices include low-energy (˜100 MeV ) and high-energy (˜1 GeV ) recirculation arcs, and medium-energy compressor arcs. Our studies show that lattices satisfying the proposed conditions indeed have microbunching gain suppressed. Beam current dependences of maximal CSR microbunching gains are also demonstrated, which should help outline a beam line design for different scales of nominal currents. We expect this analysis can shed light on the lattice design approach that aims to control the CSR-induced microbunching.

  8. High gradient magnetic beneficiation of dry pulverized coal via upwardly directed recirculating fluidization

    DOEpatents

    Eissenberg, David M.; Liu, Yin-An

    1980-01-01

    This invention relates to an improved device and method for the high gradient magnetic beneficiation of dry pulverized coal, for the purpose of removing sulfur and ash from the coal whereby the product is a dry environmentally acceptable, low-sulfur fuel. The process involves upwardly directed recirculating air fluidization of selectively sized powdered coal in a separator having sections of increasing diameters in the direction of air flow, with magnetic field and flow rates chosen for optimum separations depending upon particulate size.

  9. NASA Dryden Flight Loads Research Facility

    NASA Technical Reports Server (NTRS)

    Sefic, W. J.

    1981-01-01

    The Dryden Flight Loads Research Facility (NASA) and the associated equipment for simulating the loading and heating of aircraft or their components are described. Particular emphasis is placed on various fail-safe devices which are built into the equipment to minimize the possibility of damage to flight vehicles. The equipment described includes the ground vibration and moment of inertia equipment, the data acquisition system, and the instrumentation available in the facility for measuring load, position, strain, temperature, and acceleration.

  10. The Multistage Compressor Facility

    NASA Technical Reports Server (NTRS)

    Flegel, Ashlie

    2004-01-01

    Research and developments of new aerospace technologies is one of Glenn Research Center's specialties. One facility that deals with the research of aerospace technologies is the High-speed Multistage Compressor Facility. This facility will be testing the performance and efficiency of an Ultra Efficient Engine Technology (UEET) two-stage compressor. There is a lot of preparation involved with testing something of this caliber. Before the test article can be installed into the test rig, the facility must be fully operational and ready to run. Meaning all the necessary instrumentation must be calibrated and installed in the facility. The test rig should also be in safe operating condition, and the proper safety permits obtained. In preparation for the test, the Multistage Compressor Facility went through a few changes. For instance the facility will now be utilizing slip rings, the gearbox went through some maintenance, new lubrications systems replaced the old ones, and special instrumentation needs to be fine tuned to achieve the maximum amount of accurate data. Slips rings help gather information off of a rotating device - in this case from a shaft - onto stationary contacts. The contacts (or brushes) need to be cooled to reduce the amount of frictional heat produced between the slip ring and brushes. The coolant being run through the slip ring is AK-225, a material hazardous to the ozone. To abide by the safety regulations the coolant must be run through a closed chiller system. A new chiller system was purchased but the reservoir that holds the coolant was ventilated which doesn t make the system truly closed and sealed. My task was to design and have a new reservoir built for the chiller system that complies with the safety guidelines. The gearbox had some safety issues also. Located in the back of the gearbox an inching drive was set up. When the inching drive is in use the gears and chain are bare and someone can easily get caught up in it. So to prevent

  11. Mixer assembly for a gas turbine engine having a pilot mixer with a corner flame stabilizing recirculation zone

    NASA Technical Reports Server (NTRS)

    Dai, Zhongtao (Inventor); Cohen, Jeffrey M. (Inventor); Fotache, Catalin G. (Inventor)

    2012-01-01

    A mixer assembly for a gas turbine engine is provided, including a main mixer, and a pilot mixer having an annular housing in which a corner is formed between an aft portion of the housing and a bulkhead wall in which a corner recirculation zone is located to stabilize and anchor the flame of the pilot mixer. The pilot mixer can further include features to cool the annular housing, including in the area of the corner recirculation zone.

  12. Monitoring extent of moisture variations due to leachate recirculation in an ELR/bioreactor landfill using resistivity imaging.

    PubMed

    Manzur, Shahed Rezwan; Hossain, Md Sahadat; Kemler, Vance; Khan, Mohammad Sadik

    2016-09-01

    Bioreactor or enhanced leachate recirculation (ELR) landfills are designed and operated for accelerated waste stabilization, accelerated decomposition, and an increased rate of gas generation. The major aspects of a bioreactor landfill are the addition of liquid and the recirculation of collected leachate back into the waste mass through the subsurface leachate recirculation system (LRS). The performance of the ELR landfill largely depends on the existing moisture content within the waste mass; therefore, it is of utmost importance to determine the moisture variations within the landfill. Traditionally, the moisture variation of the ELR landfill is determined by collecting samples through a bucket auger boring from the landfill, followed by laboratory investigation. Collecting the samples through a bucket auger boring is time consuming, labor intensive, and cost prohibitive. Moreover, it provides the information for a single point within the waste mass, but not for the moisture distribution within the landfill. Fortunately, 2D resistivity imaging (RI) can be performed to assess the moisture variations within the landfill and provide a continuous image of the subsurface, which can be utilized to evaluate the performance of the ELR landfill. During this study, the 2D resistivity imaging technique was utilized to determine the moisture distribution and moisture movement during the recirculation process of an ELR landfill in Denton, Texas, USA. A horizontal recirculation pipe was selected and monitored periodically for 2.5years, using the RI technique, to investigate the performance of the leachate recirculation. The RI profile indicated that the resistivity of the solid waste decreased as much as 80% with the addition of water/leachate through the recirculation pipe. In addition, the recirculated leachate traveled laterally between 11m and 16m. Based on the resistivity results, it was also observed that the leachate flow throughout the pipe was non-uniform. The non

  13. Generation of Flat Optical Frequency Comb based on Mach-Zehnder Modulator and Recirculating Frequency Shifter Loop

    NASA Astrophysics Data System (ADS)

    Wu, Shibao; Li, Yulong; Fei, Yue; Hu, Faze

    2014-06-01

    We propose a novel scheme to generate optical frequency comb by using Mach-Zehnder modulator and recirculating frequency shifter loop based on IQ modulator driven by radio frequency clock signals. A system of 4 flat and stable comb lines generation based on Mach-Zehnder modulator is set as the seed light source of the recirculating loop. Through theorical analysis and simulation it is shown that the proposed theoretical model is proved in good agreement with simulation results.

  14. Bacterial community structure in cooling water and biofilm in an industrial recirculating cooling water system.

    PubMed

    Wang, Jinmei; Liu, Min; Xiao, Huijie; Wu, Wei; Xie, Meijuan; Sun, Mengjia; Zhu, Chenglin; Li, Pengfu

    2013-01-01

    Microbial fouling is a serious problem in open recirculating cooling water systems. The bacterial communities that cause it have not been fully understood. In this study, we analyzed the community structure of free-living bacteria and particle-attached bacteria in cooling water, and bacteria in biofilm collected from the wall of the water reservoir in an industrial recirculating cooling water system by construction of a 16S rRNA gene clone library. Based on amplified ribosomal DNA restriction analysis, clones of all three libraries were clustered into 45 operational taxonomic units (OTUs). Thirteen OTUs displaying 91-96% sequence similarity to a type strain might be novel bacterial species. Noted differences in community structure were observed among the three libraries. The relative species richness of the free-living bacteria in cooling water was much lower than that of particle-attached bacteria and bacteria in biofilm. The majority of the free-living bacterial community (99.0%) was Betaproteobacteria. The predominant bacteria in the particle-attached bacterial community were Alphaproteobacteria (20.5%), Betaproteobacteria (27.8%) and Planctomycetes (42.0%), while those in the biofilm bacterial community were Alphaproteobacteria (47.9%), Betaproteobacteria (11.7%), Acidobacteria (13.1%) and Gemmatimonadetes (11.3%). To control microbial fouling in industrial recirculating cooling water systems, additional physiological and ecological studies of these species will be essential.

  15. Bio-desulfurization of biogas using acidic biotrickling filter with dissolved oxygen in step feed recirculation.

    PubMed

    Chaiprapat, Sumate; Charnnok, Boonya; Kantachote, Duangporn; Sung, Shihwu

    2015-03-01

    Triple stage and single stage biotrickling filters (T-BTF and S-BTF) were operated with oxygenated liquid recirculation to enhance bio-desulfurization of biogas. Empty bed retention time (EBRT 100-180 s) and liquid recirculation velocity (q 2.4-7.1 m/h) were applied. H2S removal and sulfuric acid recovery increased with higher EBRT and q. But the highest q at 7.1 m/h induced large amount of liquid through the media, causing a reduction in bed porosity in S-BTF and H2S removal. Equivalent performance of S-BTF and T-BTF was obtained under the lowest loading of 165 gH2S/m(3)/h. In the subsequent continuous operation test, it was found that T-BTF could maintain higher H2S elimination capacity and removal efficiency at 175.6±41.6 gH2S/m(3)/h and 89.0±6.8% versus S-BTF at 159.9±42.8 gH2S/m(3)/h and 80.1±10.2%, respectively. Finally, the relationship between outlet concentration and bed height was modeled. Step feeding of oxygenated liquid recirculation in multiple stages clearly demonstrated an advantage for sulfide oxidation.

  16. Advanced Horizontal Well Recirculation Systems for Geothermal Energy Recovery in Sedimentary and Crystalline Formations

    SciTech Connect

    Bruno, Mike S.; Detwiler, Russell L.; Lao, Kang; Serajian, Vahid; Elkhoury, Jean; Diessl, Julia; White, Nicky

    2012-12-13

    There is increased recognition that geothermal energy resources are more widespread than previously thought, with potential for providing a significant amount of sustainable clean energy worldwide. Recent advances in drilling, completion, and production technology from the oil and gas industry can now be applied to unlock vast new geothermal resources, with some estimates for potential electricity generation from geothermal energy now on the order of 2 million megawatts. The primary objectives of this DOE research effort are to develop and document optimum design configurations and operating practices to produce geothermal power from hot permeable sedimentary and crystalline formations using advanced horizontal well recirculation systems. During Phase I of this research project Terralog Technologies USA and The University of California, Irvine (UCI), have completed preliminary investigations and documentation of advanced design concepts for paired horizontal well recirculation systems, optimally configured for geothermal energy recovery in permeable sedimentary and crystalline formations of varying structure and material properties. We have also identified significant geologic resources appropriate for application of such technology. The main challenge for such recirculation systems is to optimize both the design configuration and the operating practices for cost-effective geothermal energy recovery. These will be strongly influenced by sedimentary formation properties, including thickness and dip, temperature, thermal conductivity, heat capacity, permeability, and porosity; and by working fluid properties.

  17. Upwelling-triggered near-geostrophic recirculation in an equatorward facing embayment

    NASA Astrophysics Data System (ADS)

    Moraga-Opazo, Julio; Valle-Levinson, Arnoldo; Ramos, Marcel; Pizarro-Koch, Matías

    2011-12-01

    Underway current velocity profiles were combined with hydrographic profiles at the entrance to Tongoy Bay, an equatorward facing bay in north-central Chile, with the objective of determining its exchange hydrodynamics. To the west, Tongoy Bay is bounded by Lengua de Vaca Point, a ˜6 km-long northward protruding peninsula. Observations were obtained during three surveys (April 2005, December 2005, May 2009) along cross-bay transects for at least one full day. During the surveys, winds were upwelling-favorable and displayed diurnal variations. Non-tidal (tidally averaged) flows showed a consistent clockwise or southern hemisphere cyclonic, recirculation during the three surveys. This recirculation was likely part of a cyclonic gyre (10-20 km in diameter), not entirely resolved by the surveys, and formed by flow separation off Lengua de Vaca Point. Estimates of the baroclinic pressure gradient, combined with analytical solutions of density-driven and wind-driven flows, indicated that the recirculation in Tongoy Bay was nearly in geostrophic balance. An ageostrophic contribution to the dynamics was related to frictional effects derived from local upwelling-favorable winds. A linear superposition of the analytically derived density-driven and wind-driven exchange resulted in a flow pattern that resembled the observed net exchange flows at the bay mouth.

  18. DOE LeRC photovoltaic systems test facility

    NASA Technical Reports Server (NTRS)

    Cull, R. C.; Forestieri, A. F.

    1978-01-01

    The facility was designed and built and is being operated as a national facility to serve the needs of the entire DOE National Photovoltaic Program. The object of the facility is to provide a place where photovoltaic systems may be assembled and electrically configured, without specific physical configuration, for operation and testing to evaluate their performance and characteristics. The facility as a breadboard system allows investigation of operational characteristics and checkout of components, subsystems and systems before they are mounted in field experiments or demonstrations. The facility as currently configured consist of 10 kW of solar arrays built from modules, two inverter test stations, a battery storage system, interface with local load and the utility grid, and instrumentation and control necessary to make a flexible operating facility. Expansion to 30 kW is planned for 1978. Test results and operating experience are summaried to show the variety of work that can be done with this facility.

  19. The recirculation of the intermediate western boundary current at the Tubarão Bight - Brazil

    NASA Astrophysics Data System (ADS)

    Costa, Vladimir S.; Mill, Guilherme N.; Gabioux, Mariela; Grossmann-Matheson, Guisela S.; Paiva, Afonso M.

    2017-02-01

    Lagrangian floats and current meter measurements from two moored arrays are analyzed, in combination with altimetry data, in order to investigate the recirculation of Antarctic Intermediate Waters (AAIW), and of the Intermediate Western Boundary Current (IWBC) at the Tubarão Bight, in the vicinity of the Vitória-Trindade Ridge (VTR), Brazil. Results from a high-resolution numerical simulation provide a complementary view of the flow at intermediate and surface levels. The data depict a topographically-induced cyclonic recirculation at intermediate levels, and five Argo floats are successively trapped inside the bight for two-and-a-half years, performing a total of 10 closed clockwise gyres during this period of time. In situ measurements at the western side of the bight show an intense alongshore flow at intermediate levels, with averaged velocities at 800 m of 30 cm/s, and peak velocities exceeding 50 cm/s, magnitudes comparable to the Brazil Current (BC) flow at surface levels. The recirculation extends from at least 1000 m deep up to 370 m, reaching sometimes depths as shallow as 150 m, but is mostly uncoupled from the surface flow during the one-and-a-half year long current meter record. Three different flow patterns are observed, and simulated, at surface levels inside the bight during the time the recirculation is well established at intermediate levels: a shallow cyclonic circulation, somewhat akin to the Vitória Eddy; a recurrent anticyclonic flow that encompasses the entire bight; and a southwestward-oriented circulation, associated with the BC being reorganized in a coherent flow after negotiating its way through the VTR channels. A significant portion (about 50% according to the model) of the inflow of intermediate waters recirculates, enhancing the flow of the IWBC within the bight, and increasing the age of AAIW that will eventually cross the VTR on its way to lower latitudes. Although the data are not conclusive about a preferential pathway of the

  20. A one-dimensional ice structure built from pentagons.

    PubMed

    Carrasco, Javier; Michaelides, Angelos; Forster, Matthew; Haq, Sam; Raval, Rasmita; Hodgson, Andrew

    2009-05-01

    Heterogeneous ice nucleation has a key role in fields as diverse as atmospheric chemistry and biology. Ice nucleation on metal surfaces affords an opportunity to watch this process unfold at the molecular scale on a well-defined, planar interface. A common feature of structural models for such films is that they are built from hexagonal arrangements of molecules. Here we show, through a combination of scanning tunnelling microscopy, infrared spectroscopy and density-functional theory, that about 1-nm-wide ice chains that nucleate on Cu(110) are not built from hexagons, but instead are built from a face-sharing arrangement of water pentagons. The pentagon structure is favoured over others because it maximizes the water-metal bonding while maintaining a strong hydrogen-bonding network. It reveals an unanticipated structural adaptability of water-ice films, demonstrating that the presence of the substrate can be sufficient to favour non-hexagonal structural units.

  1. The microbiome of the built environment and mental health.

    PubMed

    Hoisington, Andrew J; Brenner, Lisa A; Kinney, Kerry A; Postolache, Teodor T; Lowry, Christopher A

    2015-12-17

    The microbiome of the built environment (MoBE) is a relatively new area of study. While some knowledge has been gained regarding impacts of the MoBE on the human microbiome and disease vulnerability, there is little knowledge of the impacts of the MoBE on mental health. Depending on the specific microbial species involved, the transfer of microorganisms from the built environment to occupant's cutaneous or mucosal membranes has the potential to increase or disrupt immunoregulation and/or exaggerate or suppress inflammation. Preclinical evidence highlighting the influence of the microbiota on systemic inflammation supports the assertion that microorganisms, including those originating from the built environment, have the potential to either increase or decrease the risk of inflammation-induced psychiatric conditions and their symptom severity. With advanced understanding of both the ecology of the built environment, and its influence on the human microbiome, it may be possible to develop bioinformed strategies for management of the built environment to promote mental health. Here we present a brief summary of microbiome research in both areas and highlight two interdependencies including the following: (1) effects of the MoBE on the human microbiome and (2) potential opportunities for manipulation of the MoBE in order to improve mental health. In addition, we propose future research directions including strategies for assessment of changes in the microbiome of common areas of built environments shared by multiple human occupants, and associated cohort-level changes in the mental health of those who spend time in the buildings. Overall, our understanding of the fields of both the MoBE and influence of host-associated microorganisms on mental health are advancing at a rapid pace and, if linked, could offer considerable benefit to health and wellness.

  2. As-Built Modeling of Ojbects for Performance Assessment

    SciTech Connect

    Kokko, E J; Martz, H E; Chinn, D J; Childs, H R; Jackson, J A; Chambers, D H; Schneberk, D J; Clark, G A

    2005-09-12

    The goal of ''as-built'' computational modeling is to incorporate the most representative geometry and material information for an (fabricated or legacy) object into simulations. While most engineering finite element simulations are based on an object's idealized ''as-designed'' configuration with information obtained from technical drawings or computer-aided design models, ''as-built'' modeling uses nondestructive characterization and metrology techniques to provide the feature information. By incorporating more representative geometry and material features as initial conditions, the uncertainty in the simulation results can be reduced, providing a more realistic understanding of the event and object being modeled. In this paper, key steps and technology areas in the as-built modeling framework are: (1) inspection using non-destructive characterization (NDC) and metrology techniques; (2) data reduction (signal and image processing including artifact removal, data sensor fusion, and geometric feature extraction); and (3) engineering and physics analysis using finite element codes. We illustrate the process with a cylindrical phantom and include a discussion of the key concepts and areas that need improvement. Our results show that reasonable as-built initial conditions based on a volume overlap criteria can be achieved and that notable differences between simulations of the as-built and as-designed configurations can be observed for a given load case. Specifically, a volume averaged difference of accumulated plastic strain of 3% and local spatially varying differences up to 10%. The example presented provides motivation and justification to engineering teams for the additional effort required in the as-built modeling of high value parts. Further validation of the approach has been proposed as future work.

  3. 68. Montana Theater, built on North Montana Street in 1901 ...

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

    68. Montana Theater, built on North Montana Street in 1901 as Sutton's New Grand Theatre, had a seating capacity of 2,175. In its heyday, this theater attracted the most famous acts of vaudville, opera, and theater. The upper stories are built of yellow painted brick, with terra-cotta applied in a stone pattern on the ground floor. The entrance has been modernized with a wall of glass bricks. On the north side of the theater is a four story building which provided a side entrance to the theater and had storefronts, with apartments above. - Butte Historic District, Bounded by Copper, Arizona, Mercury & Continental Streets, Butte, Silver Bow County, MT

  4. 42. (Credit JTL) No. 3 low service pumping engine built ...

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

    42. (Credit JTL) No. 3 low service pumping engine built in 1920 by Worthington Pump and Machinery Corp. (No. 2 low service pump is submerged in 1911-1912 pump pit on Cross Bayou). This engine was built with 9", 15" and 24"x24" cylinders and could pump 5 mgd; grating covers pump pit opening. Elevator in cage at extreme left descends to pit bottom allowing easier access than spiral stairway. Electric low service pump motor to left also; pump located in bottom of pit. - McNeil Street Pumping Station, McNeil Street & Cross Bayou, Shreveport, Caddo Parish, LA

  5. 69. The Imperial Block (8082 East Park) was built in ...

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

    69. The Imperial Block (80-82 East Park) was built in 1900 for stores and lodgings. The ground floor has its original cast-iron storefront. The Ivanhoe Block was built in 1905 and also served as lodgings on the upper levels, above commercial space. Its storefront is covered with wood paneling. Bay windows in the upper two floors are divided by circular arches of egg-and-dart molding. - Butte Historic District, Bounded by Copper, Arizona, Mercury & Continental Streets, Butte, Silver Bow County, MT

  6. 28 CFR 35.150 - Existing facilities.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) Swimming pools, wading pools, and spas, sections 242 and 1009. (K) Shooting facilities with firing...) Adopting other innovative methods. (4) Swimming pools, wading pools, and spas. The requirements set forth... entity chooses to make structural changes to existing swimming pools, wading pools, or spas built...

  7. Facilities Management.

    ERIC Educational Resources Information Center

    Bete, Tim, Ed.

    1998-01-01

    Presents responses from Matt McGovern, "School Planning and Management's" Maintenance and Operations columnist, on the issue of school facility maintenance. McGovern does not believe schools will ever likely meet acceptable levels of maintenance, nor use infrared thermography for assessing roofs, outsource all maintenance work, nor find…

  8. Teaching Children about Aspects of Comfort in the Built Environment

    ERIC Educational Resources Information Center

    Kowaltowski, Doris C. C. K.; Filho, Francisco Borges; Labaki, Lucila C.; Pina, Silvia A. Mikami G.; Bernardi, Nubia

    2004-01-01

    This article presents specific teaching material for the primary school level that introduces basic concepts of environmental comfort. The authors developed 2 booklets to make children aware of the built environment. Following a postoccupancy evaluation of state schools in the city of Campinas, in the state of Sao Paulo, Brazil, the research team…

  9. Stability tests of permanent magnets built with strontium ferrite

    SciTech Connect

    Glass, H.D.; Brown, B.C.; Foster, G.W.; Fowler, W.B.; Gustafson, R.; Jackson, G.P.; Ostiguy, J.F.; Volk, J.T.

    1997-06-01

    Permanent magnets built using strontium ferrite bricks have been tested for stability against demagnetization. Ten test dipoles were built to monitor ferrite behavior under a variety of stressing conditions, including irradiation, mechanical shock, extreme thermal excursions, and long term magnetization stability. The test magnets were geometrically similar to, but much shorter than, the magnets built for the 8 GeV transfer line at FNAL. No loss of magnetization was observed for bricks exposed to a proton beam, and a magnet exposed to several Gigarads of Co{sup 60} gamma radiation suffered no measurable demagnetization. The magnet strength was observed to decrease logarithmically with time, consistent with the expected effect of thermal fluctuations. Irreversible demagnetization of {approx}0.1% was seen in cooling magnets to 0{degree}C, and the loss was {approx}0.2% for magnets cooled to -20{degree}C. No additional demagnetization was seen on subsequent cycling to 0{degree}C. Finally, one of the long dipoles built for the 8 GeV line was periodically tested over the course of 3 months, and showed no measurable demagnetization.

  10. 5. HISTORIC PHOTOGRAPH OF FIRST CHRISTINE FALLS BRIDGE, BUILT BY ...

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

    5. HISTORIC PHOTOGRAPH OF FIRST CHRISTINE FALLS BRIDGE, BUILT BY U.S. ARMY CORPS OF ENGINEERS CA. 1908. PHOTOGRAPHER TAKEN 1911. MOUNT RAINIER NATIONAL PARK ARCHIVES - Christine Falls Bridge, Spanning Van Trump Creek on Nisqually Road, Longmire, Pierce County, WA

  11. Built Environment: A Teacher Introduction to Environmental Education.

    ERIC Educational Resources Information Center

    American Inst. of Architects, Washington, DC.

    This environmental education teacher's guide focuses on the "built environment" or everything people have imposed on the natural physical environment. The guide provides objectives and a broad definition of environmental education, sample activities, suggestions for local consultants and resources, and an annotated list of both printed and…

  12. Built Environment Education Program Manual for Teachers and Architects.

    ERIC Educational Resources Information Center

    American Inst. of Architects, Sacramento, CA. California Council.

    This teacher's handbook is designed to educate the city builders of tomorrow about the importance of responsible urban development. The activities stress the relationship between the built and natural environment. The goals of the project emphasize: (1) sensitivity to the importance of working in greater harmony with the total environment; (2)…

  13. View north of the brick vault built into the northern ...

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

    View north of the brick vault built into the northern slope of Mount Zion Cemetery with Rock Creek and Rock Creek Park beyond the trees. - Mount Zion Cemetery/ Female Union Band Cemetery, Bounded by 27th Street right-of-way N.W. (formerly Lyons Mill Road), Q Street N.W., & Mill Road N.W., Washington, District of Columbia, DC

  14. View west of the front of the brick vault built ...

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

    View west of the front of the brick vault built into the northern slope of Mount Zion Cemetery. - Mount Zion Cemetery/ Female Union Band Cemetery, Bounded by 27th Street right-of-way N.W. (formerly Lyons Mill Road), Q Street N.W., & Mill Road N.W., Washington, District of Columbia, DC

  15. Does Built Environment Matter to Early Adolescents' Physical Activity?

    ERIC Educational Resources Information Center

    Lin, Jen-Jia; Ting, Tzu-Cheng

    2014-01-01

    This study examined the relationship of built environments to physical activity among adolescents aged 12 to 14 years old. The study sample included 269 junior high school students studying in Nangang District, Taipei, Taiwan. Sample physical activity data were obtained by surveying adolescents using a self-administered short version of the…

  16. 6. EXTERIOR VIEW OF DEVELOPMENT BUILDING. THIS STRUCTURE WAS BUILT ...

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

    6. EXTERIOR VIEW OF DEVELOPMENT BUILDING. THIS STRUCTURE WAS BUILT AS A CLOTH WAREHOUSE AND IS LOCATED AT THE CENTER OF AN U-SHAPED GROUPING OF WAREHOUSES IN THE HILLSIDE MILL COMPLEX. - Hillside Cotton Mill, 1300 Brownwood Avenue, La Grange, Troup County, GA

  17. Hand-Built Pottery: An Elementary Clay Project.

    ERIC Educational Resources Information Center

    Farris, Cynthia Cox

    2001-01-01

    Describes an activity that takes two class periods where fifth-grade students created hand-built pots. Explains that each child receives a clay slab. Discusses how to make the major part of the pot from two pinch pots and how to create the neck and foot. (CMK)

  18. PHOTOCOPY OF HISTORIC PHOTOGRAPH, "LAWRENCE LEVERING BECKEL (BRIDGE BUILT BY ...

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

    PHOTOCOPY OF HISTORIC PHOTOGRAPH, "LAWRENCE LEVERING BECKEL (BRIDGE BUILT BY HIM AND HIS FATHER, CHAS. N. BECKEL AT EASTON)," original ca. 1885, photographer unknown. Collection of Historic Bethlehem Inc., Bethlehem, PA, Negative Nos. 3550 or 4504. - Walnut Street Bridge, Formerly spanning Saucon Creek, Hellertown, Northampton County, PA

  19. Swale built up of drylaid basaltic rock along the Route ...

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

    Swale built up of dry-laid basaltic rock along the Route 66 section. Sandia Peak in distance, facing south. - La Bajada Historic Trails and Roads, Approximately 1 mile East/Northeast of intersection of State Highway 16 and Indian Service Road 841, La Bajada, Santa Fe County, NM

  20. Student-Built Housing as an Alternative to Dormitories

    ERIC Educational Resources Information Center

    Corbett, Judith A.

    1973-01-01

    Fourteen polyurethane foam domes were built on a college campus by students desiring to live in nonconventionalhousing and to build their own living environment. This paper gives a brief history and description of the project and an evaluation of the building process. (JP)

  1. 1. MODEL OF THE EVELINA M. GOULART AS BUILT BY ...

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

    1. MODEL OF THE EVELINA M. GOULART AS BUILT BY DR. WILLIAM G. HEISEY. IT DEPICTS THE GOULART AS SHE APPEARED IN THE SUMMER OF 1927 SHORTLY AFTER LAUNCHING AND RIGGED FOR SWORDFISHING. - Auxiliary Fishing Schooner "Evelina M. Goulart", Essex Shipbuilding Museum, 66 Main Street, Essex, Essex County, MA

  2. Was the Great Pyramid Built with Simple Machines?

    ERIC Educational Resources Information Center

    Kraft, Susan; Poynor, Leslie

    2004-01-01

    Recently one of the authors challenged her third-grade students to use their imagination and travel with her to Egypt. As they were exploring the Great Pyramid, she encouraged the students to speculate how ancient people could have built such a massive structure without the sophisticated machinery they have at our disposal today. This article…

  3. 90. Virginia Route 608 grade separation structure. Built in 1966, ...

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

    90. Virginia Route 608 grade separation structure. Built in 1966, this concrete slab structure is typical of several with scored wing walls. These were only used on secondary state roads. View to the south. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  4. 1. GUEST HOUSE KNOWN AS 'THE LODGE' REPORTEDLY BUILT TO ...

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

    1. GUEST HOUSE KNOWN AS 'THE LODGE' REPORTEDLY BUILT TO BE USED BY J.D. ROSS ON HIS VISITS TO THE SKAGIT PROJECT. DURING THE 1930S THE U.S. FOREST SERVICE EXERTED A STONG INFLUENCE ON BUILDING STYLES FOR RESIDENCES AT THE SKAGIT PROJECT, 1989. - Skagit Power Development, Skagit River & Newhalem Creek Hydroelectric Project, On Skagit River, Newhalem, Whatcom County, WA

  5. 7. Humpback Gap Overlook. View of stone railandrider fences built ...

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

    7. Humpback Gap Overlook. View of stone rail-and-rider fences built in 1943 with the curvilinear alignment of the parkway in the background. View facing southwest. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  6. Roofing: Workbook and Tests. Built-up Roofing.

    ERIC Educational Resources Information Center

    Klingensmith, Robert, Ed.

    Designed for use in roofing apprenticeship classes, this workbook contains eight units on skills used in built-up roofing, a listing of instructional materials, a glossary, and the text of Labor Code Article 30, Construction Safety Orders, "Roofing Operations and Equipment." Each instructional unit includes a listing of performance statements and…

  7. LINEN CLOSET IN THE HALL SHOWING THE BUILT IN SHELVES. ...

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

    LINEN CLOSET IN THE HALL SHOWING THE BUILT IN SHELVES. VIEW FACING SOUTHEAST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Three-Bedroom Single-Family Type 7, Birch Circle, Elm Drive, Elm Circle, and Date Drive, Pearl City, Honolulu County, HI

  8. MASTER BATH SHOWING THE LINEN CLOSET WITH BUILT IN SHELVES ...

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

    MASTER BATH SHOWING THE LINEN CLOSET WITH BUILT IN SHELVES NEXT TO THE SHOWER ENCLOSURE. VIEW FACING NORTHEAST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Three-Bedroom Single-Family Types 8 and 11, Birch Circle, Elm Drive, Elm Circle, and Date Drive, Pearl City, Honolulu County, HI

  9. An Interactive Multimedia Learning Environment for VLSI Built with COSMOS

    ERIC Educational Resources Information Center

    Angelides, Marios C.; Agius, Harry W.

    2002-01-01

    This paper presents Bigger Bits, an interactive multimedia learning environment that teaches students about VLSI within the context of computer electronics. The system was built with COSMOS (Content Oriented semantic Modelling Overlay Scheme), which is a modelling scheme that we developed for enabling the semantic content of multimedia to be used…

  10. Design in the Classroom: Exploring the Built Environment.

    ERIC Educational Resources Information Center

    Maine Arts Commission, Augusta.

    Design and the built environment are subjects of concern to Maine communities. State mandated town planning, new school construction, and the Department of Transportation plans to rebuild roads and bridges elicit public discussion. The study of design encourages elementary students to enter this public forum as informed citizens. The study of…

  11. 245. Rocky Mountain Viaduct. This steel girder viaduct was built ...

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

    245. Rocky Mountain Viaduct. This steel girder viaduct was built in 1942. All of the reinforced concrete was faced with a rusticated stone. It is the only structure on the parkway with stone faced arched piers. The view is facing east. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  12. 122. Goshen Creek Viaduct. This steel girder viaduct, built in ...

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

    122. Goshen Creek Viaduct. This steel girder viaduct, built in 1949, is the only viaduct with solid, stone-faced, concrete reinforced piers. View facing north-northeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  13. 17. Rocky Mountain viaduct. This steel girder viaduct was built ...

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

    17. Rocky Mountain viaduct. This steel girder viaduct was built in 1942. All of the reinforced concrete was faced with a rustic stone facade. View is to east. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  14. 86. Round Meadow Creek Viaduct. This steel girder bridge, built ...

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

    86. Round Meadow Creek Viaduct. This steel girder bridge, built in 1939, has a reinforced concrete deck and piers. It is an example of a major in-line, or straight, viaduct over a deep ravine. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  15. 50. (Credit JTL) Locomotivetype steam driven air compressor built by ...

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

    50. (Credit JTL) Locomotive-type steam driven air compressor built by Westinghouse Air Brake Company and located on west wall of old high service room. - McNeil Street Pumping Station, McNeil Street & Cross Bayou, Shreveport, Caddo Parish, LA

  16. Using Attributes of Natural Systems to Plan the Built Environment

    EPA Science Inventory

    The concept of 'protection' is possible only before something is lost, however, development of the built environment to meet human needs also compromises the environmental systems that sustain human life. Because maintaining an environment that is able to sustain human life requi...

  17. South elevation of Superintendent's Quarters, built as a combination staff ...

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

    South elevation of Superintendent's Quarters, built as a combination staff living quarters/office and a visitor reception room by the War Department in 1923-24. Note exterior door to Gold Star Mothers' reception room on right. - Flanders Field American Cemetery & Memorial, Superintendent's Quarters, Wortegemseweg 117, Waregem, West Flanders (Belgium)

  18. The Foundations of Lifelong Health Are Built in Early Childhood

    ERIC Educational Resources Information Center

    National Forum on Early Childhood Policy and Programs, 2010

    2010-01-01

    A vital and productive society with a prosperous and sustainable future is built on a foundation of healthy child development. Health in the earliest years--beginning with the future mother's well-being before she becomes pregnant--lays the groundwork for a lifetime of vitality. When developing biological systems are strengthened by positive early…

  19. From the Ground Up: Art in American Built Environment Education.

    ERIC Educational Resources Information Center

    Guilfoil, Joanne K.

    2000-01-01

    Provides a case for teaching children about local architecture. Describes a specific example called the Kentucky Project as a humanist approach to built environmental education that enabled middle and high school students to study their architectural heritage through a program of videos and related teaching materials. (CMK)

  20. 9. March 1960 FRONT ROOM OF THE ADDITION BUILT BY ...

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

    9. March 1960 FRONT ROOM OF THE ADDITION BUILT BY JOHN RUSSELL POPE FACING ON MOUNT VERNON PLACE. THIS WAS EITHER A LIBRARY OR A ROOM FOR DISPLAYING TROPHIES OR OBJETS D'ART. THE VIEW IS LOOKING SOUTH, THROUGH A STAIRCASE HALL, TO THE THEATER OR BALLROOM - Garrett-Jacobs House, 7, 9, 11, 13 West Mount Vernon Place, Baltimore, Independent City, MD

  1. 5. March 1960 ROOM IN BASEMENT OF THE ADDITION BUILT ...

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

    5. March 1960 ROOM IN BASEMENT OF THE ADDITION BUILT BY JOHN RUSSELL POPE, SUPPER ROOM, LOOKING NORTH 9I.E. IN THE DIRECTION OF MOUNT VERNON PLACE) - Garrett-Jacobs House, 7, 9, 11, 13 West Mount Vernon Place, Baltimore, Independent City, MD

  2. 1. Historic American Buildings Survey Erected 1822. Built by Colonel ...

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

    1. Historic American Buildings Survey Erected 1822. Built by Colonel William Rhodes. His wife Paulina Clay was the daughter of General Green Clay and sister of General Cassius Marcellus Clay, Ambassador to Russia under President Lincoln. - Woodlawn, Richmond, Madison County, KY

  3. Exterior view, westsouthwest, of Jeudevine Memorial Library. Built 18961897 and ...

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

    Exterior view, west-southwest, of Jeudevine Memorial Library. Built 1896-1897 and designed by local architect Lambert Packard, the library is an excellent example of Richardsonian Romanesque architecture. - Jeudevine Memorial Library, 93 North Main Street, Hardwick, Caledonia County, VT

  4. 12. CONCRETE STAIRWAY LEADING TO A LANDING BUILT TO HOUSE ...

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

    12. CONCRETE STAIRWAY LEADING TO A LANDING BUILT TO HOUSE THE MACHINERY AND COUNTERWEIGHT FOR THE DRUM GATE WHICH WAS NEVER INSTALLED, INSIDE THE RIGHT (WEST) BUTTRESS. CAMERA FACING NORTH. - Salinas Dam, Salinas River near Pozo Road, Santa Margarita, San Luis Obispo County, CA

  5. High-temperature helium-loop facility

    SciTech Connect

    Tokarz, R.D.

    1981-09-01

    The high-temperature helium loop is a facility for materials testing in ultrapure helium gas at high temperatures. The closed loop system is capable of recirculating high-purity helium or helium with controlled impurities. The gas loop maximum operating conditions are as follows: 300 psi pressure, 500 lb/h flow rate, and 2100/sup 0/F temperature. The two test sections can accept samples up to 3.5 in. diameter and 5 ft long. The gas loop is fully instrumented to continuously monitor all parameters of loop operation as well as helium impurities. The loop is fully automated to operate continuously and requires only a daily servicing by a qualified operator to replenish recorder charts and helium makeup gas. Because of its versatility and high degree of parameter control, the helium loop is applicable to many types of materials research. This report describes the test apparatus, operating parameters, peripheral systems, and instrumentation system.

  6. Designing for Education: Compendium of Exemplary Educational Facilities 2011

    ERIC Educational Resources Information Center

    OECD Publishing (NJ3), 2011

    2011-01-01

    "Designing for Education: Compendium of Exemplary Educational Facilities 2011" showcases over 60 recently built or refurbished educational facilities from 28 countries. Collectively, these projects demonstrate state-of-the-art design in this field and each one is lavishly illustrated with colour photos, plans and descriptions. [A free PDF is…

  7. The effect of sludge recirculation rate on a UASB-digester treating domestic sewage at 15 °C.

    PubMed

    Zhang, Lei; Hendrickx, Tim L G; Kampman, Christel; Zeeman, Grietje; Temmink, Hardy; Li, Weiguang; Buisman, Cees J N

    2012-01-01

    The anaerobic treatment of low strength domestic sewage at low temperature is an attractive and important topic at present. The upflow anaerobic sludge bed (UASB)-digester system is one of the anaerobic systems to challenge low temperature and concentrations. The effect of sludge recirculation rate on a UASB-digester system treating domestic sewage at 15 °C was studied in this research. A sludge recirculation rate of 0.9, 2.6 and 12.5% of the influent flow rate was investigated. The results showed that the total chemical oxygen demand (COD) removal efficiency rose with increasing sludge recirculation rate. A sludge recirculation rate of 0.9% of the influent flow rate led to organic solids accumulation in the UASB reactor. After the sludge recirculation rate increased from 0.9 to 2.6%, the stability of the UASB sludge was substantially improved from 0.37 to 0.15 g CH₄-COD/g COD, and the bio-gas production in the digester went up from 2.9 to 7.4 L/d. The stability of the UASB sludge and bio-gas production in the digester were not significantly further improved by increasing sludge recirculation rate to 12.5% of the influent flow rate, but the biogas production in the UASB increased from 0.37 to 1.2 L/d. It is recommended to apply a maximum sludge recirculation rate of 2-2.5% of the influent flow rate in a UASB-digester system, as this still allows energy self-sufficiency of the system.

  8. Kimballton Underground Research Facility

    NASA Astrophysics Data System (ADS)

    Rountree, Steven Derek

    2014-03-01

    The Kimballton Underground Research Facility (KURF) is an operating deep underground research facility with six active projects, and greater than 50 trained researchers. KURF is 30 minutes from the Virginia Tech (VT) campus in an operating limestone mine with drive-in access (eg: roll-back truck, motor coach), over 50 miles of drifts (all 40' × 20 +' the current lab is 35' × 22' × 100'), and 1700' of overburden (1450m.w.e.). The laboratory was built in 2007 and offers fiber optic internet, LN2, 480/220/110 V power, ample water, filtered air, 55 F constant temp, low Rn levels, low rock background activity, and a muon flux of only ~0.004 muons per square meter, per second, per steradian. The current users are funded by NSF, DOE, and NNSA. Current user group: 1) mini-LENS (VT, Louisiana State University, BNL); 2) Double Beta Decay to Excited States (Duke University); 3) HPGe Low-Background Screening (University of North Carolina (UNC), VT); 4) MALBEK (UNC); 5&6) Watchman - 5) Radionuclide Detector and 6) MARS detector (LLNL, SNL, UC-Davis, UC-Berkeley, UH, Hawaii Pacific, UC-Irvine, VT).

  9. Kimballton Underground Research Facility

    NASA Astrophysics Data System (ADS)

    Vogelaar, R. Bruce

    2011-10-01

    A new deep underground research facility is open and operating only 30 minutes from the Virginia Tech campus. It is located in an operating limestone mine, and has drive-in access (eg: roll-back truck, motor coach), over 50 miles of drifts (all 40' x 20' x 100'; the current lab is 35'x100'x22'), and is located where there is a 1700' overburden. The laboratory was built in 2007 and offers fiber optic internet, LN2, 480/220/110 V power, ample water, filtered air, 55 F constant temp, low Rn levels, low rock background activity, and a muon flux of only ˜ 0.004 muons per square meter, per second, per steradian. There are currently six projects using the facility: mini-LENS - Low Energy Neutrino Spectroscopy (Virginia Tech, Louisiana State University, BNL); Neutron Spectrometer (University of Maryland, NIST); Double Beta Decay to Excited States (Duke University); HPGe Low-Background Screening (North Carolina State University, University of North Carolina, Virginia Tech); MALBEK - Majorana neutrinoless double beta decay (University of North Carolina); Ar-39 Depleted Argon (Princeton University). I will summarize the current program, and exciting plans for the future.

  10. Kimballton Underground Research Facility

    NASA Astrophysics Data System (ADS)

    Rountree, S. Derek; Vogelaar, R. Bruce

    2012-03-01

    A new deep underground research facility is open and operating only 30 minutes from the Virginia Tech campus. It is located in an operating limestone mine, and has drive-in access (eg: roll-back truck, motor coach), over 50 miles of drifts (all 40' x 20+'; the current lab is 35' x 22' x 100'), and is located where there is a 1700' overburden. The laboratory was built in 2007 and offers fiber optic internet, LN2, 480/220/110 V power, ample water, filtered air, 55 F constant temp, low Rn levels, low rock background activity, and a muon flux of only ˜0.004 muons per square meter, per second, per steradian. There are currently six projects using the facility: mini-LENS - Low Energy Neutrino Spectroscopy (Virginia Tech, Louisiana State University, BNL); Neutron Spectrometer (University of Maryland, NIST); Double Beta Decay to Excited States (Duke University); HPGe Low-Background Screening (North Carolina State University, University of North Carolina, Virginia Tech); MALBEK - Majorana neutrinoless double beta decay (University of North Carolina); Ar-39 Depleted Argon (Princeton University). I will summarize the current program and exciting potential for the future.

  11. Variable gravity research facility

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Eight fourth-year engineering design students formed two teams to study methods of varying the perceived gravity level in a variable gravity research facility. A tether system and an arm system were the chosen topics. Both teams have produced and built scale models of their design. In addition, a three-credit Special Topics Course (Aviation 370) was formed, as the project offers an excellent opportunity to build a multi-disciplinary program around the initial conceptualization process. Fifty students were registered in the Special Topics course. Each week during a three hour class, a guest lecturer covered one or more of the many areas associated with the concept of a variable-gravity facility. The students formed small groups organized on a multi-disciplinary basis (there were twelve separate disciplines represented by one or more students) where they discussed among themselves the various issues involved. These groups also met outside class for three or more hours each week. During class each group presented oral reports on their findings during a one-hour general question and answer period.

  12. Relationships between the built environment and walking and weight status among older women in three U.S. States.

    PubMed

    Troped, Philip J; Starnes, Heather A; Puett, Robin C; Tamura, Kosuke; Cromley, Ellen K; James, Peter; Ben-Joseph, Eran; Melly, Steven J; Laden, Francine

    2014-01-01

    There are few studies of built environment associations with physical activity and weight status among older women in large geographic areas that use individual residential buffers to define environmental exposures. Among 23,434 women (70.0 ± 6.9 yr; range = 57-85) in 3 states, relationships between objective built environment variables and meeting physical activity recommendations via walking and weight status were examined. Differences in associations by population density and state were explored in stratified models. Population density (odds ratio [OR] =1.04 [1.02, 1.07]), intersection density (ORs = 1.18-1.28), and facility density (ORs = 1.01-1.53) were positively associated with walking. Density of physical activity facilities was inversely associated with overweight/obesity (OR = 0.69 [0.49, 0.96]). The strongest associations between facility density variables and both outcomes were found among women from higher population density areas. There was no clear pattern of differences in associations across states. Among older women, relationships between accessible facilities and walking may be most important in more densely populated settings.

  13. The potential use of constructed wetlands in a recirculating aquaculture system for shrimp culture.

    PubMed

    Lin, Ying-Feng; Jing, Shuh-Ren; Lee, Der-Yuan

    2003-01-01

    A pilot-scale constructed wetland unit, consisting of free water surface (FWS) and subsurface flow (SF) constructed wetlands arranged in series, was integrated into an outdoor recirculating aquaculture system (RAS) for culturing Pacific white shrimp (Litopenaeus vannamei). This study evaluated the performance of the wetland unit in treating the recirculating wastewater and examined the effect of improvement in water quality of the culture tank on the growth and survival of shrimp postlarvae. During an 80-day culture period, the wetland unit operated at a mean hydraulic loading rate of 0.3 m/day and effectively reduced the influent concentrations of 5-day biochemical oxygen demand (BOD5, 24%), suspended solids (SS, 71%), chlorophyll a (chl-a, 88%), total ammonium (TAN, 57%), nitrite nitrogen (NO2-N, 90%) and nitrate nitrogen (NO3-N, 68%). Phosphate (PO4-P) reduction was the least efficient (5.4%). The concentrations of SS, Chl-a, turbidity and NO3-N in the culture tank water in RAS were significantly (Precirculating system.

  14. Partitioning sources of recharge in environments with groundwater recirculation using carbon-14 and CFC-12

    NASA Astrophysics Data System (ADS)

    Bourke, Sarah A.; Cook, Peter G.; Dogramaci, Shawan; Kipfer, Rolf

    2015-06-01

    Groundwater recirculation occurs when groundwater is pumped from an aquifer onto the land surface, and a portion of that water subsequently infiltrates back to the aquifer. In environments where groundwater is recirculated, differentiation between various sources of recharge (e.g. natural rainfall recharge vs. recirculated water) can be difficult. Groundwater age indicators, in particular transient trace gases, are likely to be more sensitive tracers of recharge than stable isotopes or chloride in this setting. This is because, unlike stable isotopes or chloride, they undergo a process of equilibration with the atmosphere, and historical atmospheric concentrations are known. In this paper, groundwater age indicators (14C and CFC-12) were used as tracers of recharge by surplus mine water that is discharged to streams. Ternary mixing ratios were calculated based on 14C and CFC-12 concentrations measured along three transects of piezometers and monitoring wells perpendicular to the creeks, and from dewatering wells. Uncertainty in calculated mixing ratios was estimated using a Monte Carlo approach. Ternary mixing ratios in dewatering wells suggest that recharge by mine water accounted for between 10% and 87% of water currently abstracted by dewatering wells. The calculated mixing ratios suggest that recharge by mine water extends to a distance of more than 550 m from the creeks. These results are supported by seepage flux estimates based on the water and chloride balance along the creeks, which suggest that 85-90% of mine water discharged to the creeks recharges the aquifer and recharge by mine water extends between 110 and 730 m from the creeks. Mixing calculations based on gaseous groundwater age indicators could also be used to partition recharge associated with agricultural irrigation or artificial wetland supplementation.

  15. Inferring heat recirculation and albedo for exoplanetary atmospheres: Comparing optical phase curves and secondary eclipse data

    NASA Astrophysics Data System (ADS)

    von Paris, P.; Gratier, P.; Bordé, P.; Selsis, F.

    2016-03-01

    Context. Basic atmospheric properties, such as albedo and heat redistribution between day- and nightsides, have been inferred for a number of planets using observations of secondary eclipses and thermal phase curves. Optical phase curves have not yet been used to constrain these atmospheric properties consistently. Aims: We model previously published phase curves of CoRoT-1b, TrES-2b, and HAT-P-7b, and infer albedos and recirculation efficiencies. These are then compared to previous estimates based on secondary eclipse data. Methods: We use a physically consistent model to construct optical phase curves. This model takes Lambertian reflection, thermal emission, ellipsoidal variations, and Doppler boosting, into account. Results: CoRoT-1b shows a non-negligible scattering albedo (0.11 < AS < 0.3 at 95% confidence) as well as small day-night temperature contrasts, which are indicative of moderate to high re-distribution of energy between dayside and nightside. These values are contrary to previous secondary eclipse and phase curve analyses. In the case of HAT-P-7b, model results suggest a relatively high scattering albedo (AS ≈ 0.3). This confirms previous phase curve analysis; however, it is in slight contradiction to values inferred from secondary eclipse data. For TrES-2b, both approaches yield very similar estimates of albedo and heat recirculation. Discrepancies between recirculation and albedo values as inferred from secondary eclipse and optical phase curve analyses might be interpreted as a hint that optical and IR observations probe different atmospheric layers, hence temperatures.

  16. 26 CFR 1.1374-2 - Net recognized built-in gain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 11 2013-04-01 2013-04-01 false Net recognized built-in gain. 1.1374-2 Section... Net recognized built-in gain. (a) In general. An S corporation's net recognized built-in gain for any... corporations and considering only its recognized built-in gain, recognized built-in loss, and recognized...

  17. 26 CFR 1.1374-2 - Net recognized built-in gain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 11 2014-04-01 2014-04-01 false Net recognized built-in gain. 1.1374-2 Section... Net recognized built-in gain. (a) In general. An S corporation's net recognized built-in gain for any... amount by which its net unrealized built-in gain exceeds its net recognized built-in gain for all...

  18. 26 CFR 1.1374-2 - Net recognized built-in gain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 11 2012-04-01 2012-04-01 false Net recognized built-in gain. 1.1374-2 Section... Net recognized built-in gain. (a) In general. An S corporation's net recognized built-in gain for any... amount by which its net unrealized built-in gain exceeds its net recognized built-in gain for all...

  19. 26 CFR 1.1374-2 - Net recognized built-in gain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 11 2011-04-01 2011-04-01 false Net recognized built-in gain. 1.1374-2 Section... Net recognized built-in gain. (a) In general. An S corporation's net recognized built-in gain for any... corporations and considering only its recognized built-in gain, recognized built-in loss, and recognized...

  20. An experimental study of catalytic and non-catalytic reaction in heat recirculating reactors and applications to power generation

    NASA Astrophysics Data System (ADS)

    Ahn, Jeongmin

    An experimental study of the performance of a Swiss roll heat exchanger and reactor was conducted, with emphasis on the extinction limits and comparison of results with and without Pt catalyst. At Re<40, the catalyst was required to sustain reaction; with the catalyst self-sustaining reaction could be obtained at Re less than 1. Both lean and rich extinction limits were extended with the catalyst, though rich limits were extended much further. At low Re, the lean extinction limit was rich of stoichiometric and rich limit had equivalence ratios 80 in some cases. Non-catalytic reaction generally occurred in a flameless mode near the center of the reactor. With or without catalyst, for sufficiently robust conditions, a visible flame would propagate out of the center, but this flame could only be re-centered with catalyst. Gas chromatography indicated that at low Re, CO and non-C3 H8 hydrocarbons did not form. For higher Re, catalytic limits were slightly broader but had much lower limit temperatures. At sufficiently high Re, catalytic and gas-phase limits merged. Experiments with titanium Swiss rolls have demonstrated reducing wall thermal conductivity and thickness leads to lower heat losses and therefore increases operating temperatures and extends flammability limits. By use of Pt catalysts, reaction of propane-air mixtures at temperatures 54°C was sustained. Such low temperatures suggest that polymers may be employed as a reactor material. A polyimide reactor was built and survived prolonged testing at temperatures up to 500°C. Polymer reactors may prove more practical for microscale devices due to their lower thermal conductivity and ease of manufacturing. Since the ultimate goal of current efforts is to develop combustion driven power generation devices at MEMS like scales, a thermally self-sustaining miniature power generation device was developed utilizing a single-chamber solid-oxide-fuel-cell (SOFC) placed in a Swiss roll. With the single-chamber design

  1. An Rf-gun-driven recirculated linac as injector and FEL driver.

    SciTech Connect

    Andersson, A.; Biedron, S.; Eriksson, M.; Freund, H.; Werin, S.

    1999-08-23

    A new pre-injector for the MAX-Laboratory is under design and construction. A thermionic rf gun, designed to operate at medium currents with low back bombardment power, is under construction. The gun will, via a magnetic compressor and energy filter, feed a recirculated linac consisting of two SLED-equipped structures giving 125 MeV each. The first will be delivered in 1999. The system is aimed as a pre-injector for the existing storage rings at MAX-Lab, but will also open up possibilities for a SASE FEL in the UV reaching above 100 MW below 100 run.

  2. Involvement of Sialic Acid on Endothelial Cells in Organ-Specific Lymphocyte Recirculation

    NASA Astrophysics Data System (ADS)

    Rosen, Steven D.; Singer, Mark S.; Yednock, Ted A.; Stoolman, Lloyd M.

    1985-05-01

    Mouse lymphocytes incubated on cryostat-cut sections of lymphoid organs (lymph nodes and Peyer's patches) specifically adhere to the endothelium of high endothelial venules (HEV), the specialized blood vessels to which recirculating lymphocytes attach as they migrate from the blood into the parenchyma of the lymphoid organs. Treatment of sections with sialidase eliminated the binding of lymphocytes to peripheral lymph node HEV, had no effect on binding to Peyer's patch HEV, and had an intermediate effect on mesenteric lymph node HEV. These results suggest that sialic acid on endothelial cells may be an organ-specific recognition determinant for lymphocyte attachment.

  3. STS-35 Columbia, OV-102, aft fuselage LRU hydrogen recirculation pump

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Closeup view shows the aft fuselage line replaceable unit (LRU) hydrogen recirculation pump from Columbia, Orbiter Vehicle (OV) 102. The pump is being tested at JSC's Thermochemical Test Area (TTA) Support Laboratory Bldg 350. JSC technicians ran the pump package through the battery of leak tests. Preliminary indications showed only minor, acceptable leakage from the package and Kennedy Space Center (KSC) technicians have replaced a crushed seal on the prevalve of the main propulsion system they believe may have caused the STS-35 hydrogen leak.

  4. Three-dimensional predictions of reactive turbulent recirculating flow of a cylindrical MHD type combustor

    NASA Astrophysics Data System (ADS)

    Lee, J. J.

    1990-01-01

    A computational procedure is employed to predict the axisymmetric reactive turbulent recirculating flow-field within a cylindrical MHD combustor. The procedure used in the analysis is an extended version of the three-dimensional Combustor Performance Program developed at the Garrett Turbine Engine Company. The separated flow created by four liquid fuel nozzles and 148 oxidizer holes passing through an injector plate is examined. Numerical results for flow, heat/mass transfer and combustion are presented to describe these complex three-dimensional interactions. The detailed analysis achieved by the numerical model is useful for evaluating combustor performance and in the interpretation of laboratory test data.

  5. Recirculation of reverse osmosis concentrate in lab-scale anaerobic and aerobic landfill simulation reactors.

    PubMed

    Morello, Luca; Cossu, Raffaello; Raga, Roberto; Pivato, Alberto; Lavagnolo, Maria Cristina

    2016-10-01

    Leachate treatment is a major issue in the context of landfill management, particularly in view of the consistent changes manifested over time in the quality and quantity of leachate produced, linked to both waste and landfill characteristics, which renders the procedure technically difficult and expensive. Leachate recirculation may afford a series of potential advantages, including improvement of leachate quality, enhancement of gas production, acceleration of biochemical processes, control of moisture content, as well as nutrients and microbe migration within the landfill. Recirculation of the products of leachate treatment, such as reverse osmosis (RO) concentrate, is a less common practice, with widespread controversy relating to its suitability, potential impacts on landfill management and future gaseous and leachable emissions. Scientific literature provides the results of only a few full-scale applications of concentrate recirculation. In some cases, an increase of COD and ammonium nitrogen in leachate was observed, coupled with an increase of salinity; which, additionally, might negatively affect performance of the RO plant itself. In other cases, not only did leachate production not increase significantly but the characteristics of leachate extracted from the well closest to the re-injection point also remained unchanged. This paper presents the results of lab-scale tests conducted in landfill simulation reactors, in which the effects of injection of municipal solid waste (MSW) landfill leachate RO concentrate were evaluated. Six reactors were managed with different weekly concentrate inputs, under both anaerobic and aerobic conditions, with the aim of investigating the short and long-term effects of this practice on landfill emissions. Lab-scale tests resulted in a more reliable identification of compound accumulation and kinetic changes than full-scale applications, further enhancing the development of a mass balance in which gaseous emissions and waste

  6. Flowing recirculated-water system for inducing laboratory spawning of sea lampreys

    USGS Publications Warehouse

    Fredricks, Kim T.; Seelye, James G.

    1995-01-01

    We describe a water-recirculating system for inducing spawning of sea lampreys (Petromyzon marinus) held under laboratory conditions. Water temperature in the system was gradually increased to and maintained at 18 +/- 2 degrees C, the optimal temperature for spawning. About 10% freshwater was added daily to prevent buildup of waste products. Sea lampreys were provided substrate (approximately 3-6 cm in diameter) to build nests, and a water velocity of 0.2-0.3 m/s was maintained with an electric trolling motor. Sea lampreys held in this system exhibited characteristic spawning behavior. Prolarvae produced from artificial fertilization of gametes developed according to the standard timeline.

  7. An advanced anaerobic biofilter with effluent recirculation for phenol removal and methane production in treatment of coal gasification wastewater.

    PubMed

    Li, Yajie; Tabassum, Salma; Zhang, Zhenjia

    2016-09-01

    An advanced anaerobic biofilter (AF) was introduced for the treatment of coal gasification wastewater (CGW), and effluent recirculation was adopted to enhance phenol removal and methane production. The results indicated that AF was reliable in treating diluted CGW, while its efficiency and stability were seriously reduced when directly treating raw CGW. However, its performance could be greatly enhanced by effluent recirculation. Under optimal effluent recirculation of 0.5 to the influent, concentrations of chemical oxygen demand (COD) and total phenol in the effluent could reach as low as 234.0 and 14.2mg/L, respectively. Also, the rate of methane production reached 169.0mLCH4/L/day. Though CGW seemed to restrain the growth of anaerobic microorganisms, especially methanogens, the inhibition was temporary and reversible, and anaerobic bacteria presented strong tolerance. The activities of methanogens cultivated in CGW could quickly recover on feeding with glucose wastewater (GW). However, the adaptability of anaerobic bacteria to the CGW was very poor and the activity of methanogens could not be improved by long-term domestication. By analysis using the Haldane model, it was further confirmed that high effluent recirculation could result in high activity for hydrolytic bacteria and substrate affinity for toxic matters, but only suitable effluent recirculation could result in high methanogenic activity.

  8. Efficiency analysis of a hydrogen-fueled solid oxide fuel cell system with anode off-gas recirculation

    NASA Astrophysics Data System (ADS)

    Peters, Roland; Deja, Robert; Engelbracht, Maximilian; Frank, Matthias; Nguyen, Van Nhu; Blum, Ludger; Stolten, Detlef

    2016-10-01

    This study analyzes different hydrogen-fueled solid oxide fuel cell (SOFC) system layouts. It begins with a simple system layout without any anode off-gas recirculation, continues with a configuration equipped with off-gas recirculation, including steam condensation and then considers a layout with a dead-end anode off-gas loop. Operational parameters such as stack fuel utilization, as well as the recirculation rate, are modified, with the aim of achieving the highest efficiency values. Drawing on experiments and the accumulated experience of the SOFC group at the Forschungszentrum Jülich, a set of operational parameters were defined and applied to the simulations. It was found that anode off-gas recirculation, including steam condensation, improves electrical efficiency by up to 11.9 percentage-points compared to a layout without recirculation of the same stack fuel utilization. A system layout with a dead-end anode off-gas loop was also found to be capable of reaching electrical efficiencies of more than 61%.

  9. Influence of recirculation on the performance of anaerobic sequencing batch biofilm reactor (AnSBBR) treating hypersaline composite chemical wastewater.

    PubMed

    Mohan, S Venkata; Lalit Babu, V; Vijaya Bhaskar, Y; Sarma, P N

    2007-05-01

    Influence of recirculation on the performance of anaerobic sequencing batch biofilm reactor (AnSBBR) was studied in the process of treating hypersaline (total dissolved inorganic solids (TDIS) approximately 26 g/l) and low biodegradable (BOD/COD approximately 0.3) composite chemical wastewater. Significant enhancement in the substrate removal efficiency and biogas yield was observed after introducing the recirculation to the system. Maximum efficiency (COD removal efficiency - 51%; SDR - 3.14 kg COD/cum-day) was observed at recirculation to feed (R/F) ratio of 2 (OLR - 6.15 kg C OD/cum-day; HLR - 2.30 cum (liquid)/cum day; UFV(A) - 0.023 m/h). Subsequent increase of R/F to 3 (OLR - 6.15 kg COD/cum-day; HLR - 3.07cum (liquid)/cum-day; UFV(A) - 0.035 m/h) resulted in reduction in COD removal efficiency (32%; SDR - 1.97 kg COD/cum-day). The enhanced performance of the system due to the introduction of recirculation was attributed to the improvement in the mass transfer between the substrate present in the bulk liquid and the attached biofilm. The hydrodynamic behavior due to recirculation mode of operation reduced the concentration gradient (substrate inhibition) of substrate and reaction by-products (VFA) resulting in mixed flow conditions.

  10. Characterization of a joint recirculation of concentrated leachate and leachate to landfills with a microaerobic bioreactor for leachate treatment.

    PubMed

    He, Ruo; Wei, Xiao-Meng; Tian, Bao-Hu; Su, Yao; Lu, Yu-Lan

    2015-12-01

    With comparison of a traditional landfill, a joint recirculation of concentrated leachate and leachate to landfills with or without a microaerobic reactor for leachate treatment was investigated in this study. The results showed that the joint recirculation of concentrated leachate and leachate with a microaerobic reactor for leachate treatment could not only utilize the microaerobic reactor to buffer the fluctuation of quality and quantity of leachate during landfill stabilization, but also reduce the inhibitory effect of acidic pH and high concentrations of ammonium in recycled liquid on microorganisms and accelerate the degradation of landfilled waste. After 390 days of operation, the discharge of COD and total nitrogen (TN) from the landfill with leachate pretreatment by a microaerobic reactor was 7.4 and 0.9 g, respectively, which accounted for 0.7% and 2.6% of COD, 1.9% and 7.5% of the TN discharge from the landfills without recirculation and directly recirculated with leachate and concentrated leachate, respectively. The degradation of the organic matter and biodegradable matter (BDM) in the landfill reactors could fit well with the first-order kinetics. The highest degradation of the organic matter and BDM was observed in the joint recirculation system with a microaerobic reactor for leachate treatment with the degradation constant of the first-order kinetics of 0.001 and 0.002.

  11. Design issues for a laboratory high gain fusion facility

    SciTech Connect

    Hogan, W.J.

    1987-11-02

    In an inertial fusion laboratory high gain facility, experiments will be carried out with up to 1000 MJ of thermonuclear yield. The experiment area of such a facility will include many systems and structures that will have to operate successfully in the difficult environment created by the sudden large energy release. This paper estimates many of the nuclear effects that will occur, discusses the implied design issues and suggests possible solutions so that a useful experimental facility can be built. 4 figs.

  12. One-dimensional organic photoconductive nanoribbons built on Zn-Schiff base complex

    SciTech Connect

    Liu Li; Shao Mingwang; Wang Xiuhua

    2010-03-15

    One-dimensional organic nanoribbons built on N-p-nitrophenylsalicylaldimine zinc complex were synthesized via a facile solvothermal route. The scanning electron microscope images revealed that the as-synthesized products were ribbon-like with width mainly of 300-600 nm, thickness of about 50 nm, and length of up to tens of micrometers. Fourier transform infrared spectrum was employed to characterize the structure. Ultraviolet-visible absorption and photoluminescence spectra showed that the products had good photoluminescent property and exhibited blue emission. The conductivity of a bundle of nanoribbons was also measured, which showed that the Schiff base zinc nanoribbons had good photoconductive property. This work might enrich the organic photoconductive materials and be applicable in light-controlled micro-devices or nano-devices in the future. - Graphical abstract: The Schiff base zinc nanoribbons nanowires exhibited good photoresponse under an incandescent lamp, which indicated their potential application as organic semiconductive or photoconductive nanodevices in the future.

  13. Transformers: Shape-Changing Space Systems Built with Robotic Textiles

    NASA Technical Reports Server (NTRS)

    Stoica, Adrian

    2013-01-01

    Prior approaches to transformer-like robots had only very limited success. They suffer from lack of reliability, ability to integrate large surfaces, and very modest change in overall shape. Robots can now be built from two-dimensional (2D) layers of robotic fabric. These transformers, a new kind of robotic space system, are dramatically different from current systems in at least two ways. First, the entire transformer is built from a single, thin sheet; a flexible layer of a robotic fabric (ro-fabric); or robotic textile (ro-textile). Second, the ro-textile layer is foldable to small volume and self-unfolding to adapt shape and function to mission phases.

  14. Assessment of climate vulnerability in the Norwegian built environment

    NASA Astrophysics Data System (ADS)

    Hygen, H. O.; Øyen, C. F.; Almås, A. J.

    2011-05-01

    The main trends expected for the change of Norwegian climate for this century are increasing temperatures, precipitation and wind. This indicates a probable increase of climate-related risks to the Norwegian built environment. Through co-operation between the Norwegian Meteorological Institute and SINTEF Building and Infrastructure, building and climate information have been combined to estimate changes in strain to the built environment due to climate change. The results show that the risk of wood decay will increase for the whole country. Almost two million buildings will be subject to an increase in risk of wood decay from medium to high level. Similar analyses have been performed for other climate indices, demonstrating a clear increase in potential damages due to water and humidity, while frost damage probably will decrease.

  15. Mobile Timekeeping Application Built on Reverse-Engineered JPL Infrastructure

    NASA Technical Reports Server (NTRS)

    Witoff, Robert J.

    2013-01-01

    Every year, non-exempt employees cumulatively waste over one man-year tracking their time and using the timekeeping Web page to save those times. This app eliminates this waste. The innovation is a native iPhone app. Libraries were built around a reverse- engineered JPL API. It represents a punch-in/punch-out paradigm for timekeeping. It is accessible natively via iPhones, and features ease of access. Any non-exempt employee can natively punch in and out, as well as save and view their JPL timecard. This app is built on custom libraries created by reverse-engineering the standard timekeeping application. Communication is through custom libraries that re-route traffic through BrowserRAS (remote access service). This has value at any center where employees track their time.

  16. The urban built environment and associations with women's psychosocial health.

    PubMed

    Messer, Lynne C; Maxson, Pamela; Miranda, Marie Lynn

    2013-10-01

    The determinants that underlie a healthy or unhealthy pregnancy are complex and not well understood. We assess the relationship between the built environment and maternal psychosocial status using directly observed residential neighborhood characteristics (housing damage, property disorder, tenure status, vacancy, security measures, violent crime, and nuisances) and a wide range of psychosocial attributes (interpersonal support evaluation list, self-efficacy, John Henryism active coping, negative partner support, Perceived Stress Scale, perceived racism, Center for Epidemiologic Studies-Depression) on a pregnant cohort of women living in the urban core of Durham, NC, USA. We found some associations between built environment characteristic and psychosocial health varied by exposure categorization approach, while others (residence in environments with more rental property is associated with higher reported active coping and negative partner support) were consistent across exposure categorizations. This study outlines specific neighborhood characteristics that are modifiable risk markers and therefore important targets for increased research and public health intervention.

  17. 75. The Pekin Noodle Parlor was built in 1909 at ...

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

    75. The Pekin Noodle Parlor was built in 1909 at 115-119 South Main Street. Originally it housed a gambling room and saloon in the east section of the ground floor, and a Chinese herb doctor's office in the north. The noodle parlor was on the second floor. The storefront has not been altered, and features a decorative wooden entablature. - Butte Historic District, Bounded by Copper, Arizona, Mercury & Continental Streets, Butte, Silver Bow County, MT

  18. RED or READ: the built environment is colored

    NASA Astrophysics Data System (ADS)

    Smith, Dianne

    2002-06-01

    How important is color in the design of our built environment? Prototypes and massing models for designs are often presented in white or monochromatic combinations, irrespective of the materials incorporated and the colors that may be applied in the final constructed building, interior or object. Therefore, it is of interest to identify the way color is positioned by designers in how they go about the business of making environments. The built environment is understood by the designers and design researchers generally in one of four fields - as object, as product, as communicator, or as social domain. In addition, Franz identified four conceptions of designing held by designers - the experiential conception, the structural conception, the production conception and the retail conception. Fashion and style are often associated with color in a local context and may simply be applied to the physical environment because it is in fashion, rather than because of what it communicates more broadly. It is assumed that the integration of color in the built environment is influenced by these understandings. In order to address color's position in the design process and the importance of color in relation to space, form, and the experience of place, a selection of Queensland architects and interior designers were surveyed. The study is not conclusive, however, it does identify differences and commonalities between the participants that are of interest in light of the above issues. Explorations into environmental meaning, in addition to color theory and decorative applications, are hypothesized to be important sources of information for designers involved in the coloration of the built environment.

  19. VIEW OF BUILDING 111 LOOKING EAST, NORTHEAST. BUILDING 111, BUILT ...

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

    VIEW OF BUILDING 111 LOOKING EAST, NORTHEAST. BUILDING 111, BUILT IN 1953, WAS ONE OF THE FIRST TEN PERMANENT STRUCTURES ON THE ROCKY FLATS PLANT. THE BUILDING SERVED AS AN ENTRY POINT FOR SITE EMPLOYEES AND HOUSED A PRINT SHOP AND PHOTOGRAPHY LAB. (12/26/52) - Rocky Flats Plant, Offices, Print Shop & Photography Lab, Northwest quad of plant near terminus of Central Avenue, Golden, Jefferson County, CO

  20. 52. Virginia Route 666. This single span structure, built in ...

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

    52. Virginia Route 666. This single span structure, built in 1962, is an example of a spandrel arch grade separation structure with a roman arch over a state secondary road. The bridge is constructed of reinforced concrete, backfilled with earth and has a thick stone veneer. Looking east-northeast at elevation. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  1. Built Environment, Selected Risk Factors and Major Cardiovascular Disease Outcomes: A Systematic Review

    PubMed Central

    Malambo, Pasmore; Kengne, Andre P.; De Villiers, Anniza; Lambert, Estelle V.; Puoane, Thandi

    2016-01-01

    Introduction Built environment attributes have been linked to cardiovascular disease (CVD) risk. Therefore, identifying built environment attributes that are associated with CVD risk is relevant for facilitating effective public health interventions. Objective To conduct a systematic review of literature to examine the influence of built environmental attributes on CVD risks. Data Source Multiple database searches including Science direct, CINAHL, Masterfile Premier, EBSCO and manual scan of reference lists were conducted. Inclusion Criteria Studies published in English between 2005 and April 2015 were included if they assessed one or more of the neighborhood environmental attributes in relation with any major CVD outcomes and selected risk factors among adults. Data Extraction Author(s), country/city, sex, age, sample size, study design, tool used to measure neighborhood environment, exposure and outcome assessments and associations were extracted from eligible studies. Results Eighteen studies met the inclusion criteria. Most studies used both cross-sectional design and Geographic Information System (GIS) to assess the neighborhood environmental attributes. Neighborhood environmental attributes were significantly associated with CVD risk and CVD outcomes in the expected direction. Residential density, safety from traffic, recreation facilities, street connectivity and high walkable environment were associated with physical activity. High walkable environment, fast food restaurants, supermarket/grocery stores were associated with blood pressure, body mass index, diabetes mellitus and metabolic syndrome. High density traffic, road proximity and fast food restaurants were associated with CVDs outcomes. Conclusion This study confirms the relationship between neighborhood environment attributes and CVDs and risk factors. Prevention programs should account for neighborhood environmental attributes in the communities where people live. PMID:27880835

  2. Computational investigations of low-emission burner facilities for char gas burning in a power boiler

    NASA Astrophysics Data System (ADS)

    Roslyakov, P. V.; Morozov, I. V.; Zaychenko, M. N.; Sidorkin, V. T.

    2016-04-01

    Various variants for the structure of low-emission burner facilities, which are meant for char gas burning in an operating TP-101 boiler of the Estonia power plant, are considered. The planned increase in volumes of shale reprocessing and, correspondingly, a rise in char gas volumes cause the necessity in their cocombustion. In this connection, there was a need to develop a burner facility with a given capacity, which yields effective char gas burning with the fulfillment of reliability and environmental requirements. For this purpose, the burner structure base was based on the staging burning of fuel with the gas recirculation. As a result of the preliminary analysis of possible structure variants, three types of early well-operated burner facilities were chosen: vortex burner with the supply of recirculation gases into the secondary air, vortex burner with the baffle supply of recirculation gases between flows of the primary and secondary air, and burner facility with the vortex pilot burner. Optimum structural characteristics and operation parameters were determined using numerical experiments. These experiments using ANSYS CFX bundled software of computational hydrodynamics were carried out with simulation of mixing, ignition, and burning of char gas. Numerical experiments determined the structural and operation parameters, which gave effective char gas burning and corresponded to required environmental standard on nitrogen oxide emission, for every type of the burner facility. The burner facility for char gas burning with the pilot diffusion burner in the central part was developed and made subject to computation results. Preliminary verification nature tests on the TP-101 boiler showed that the actual content of nitrogen oxides in burner flames of char gas did not exceed a claimed concentration of 150 ppm (200 mg/m3).

  3. Evaluation of personal and built environment attributes to physical activity: a multilevel analysis on multiple population-based data sources.

    PubMed

    Yang, Wei; Spears, Karen; Zhang, Fan; Lee, Wai; Himler, Heidi L

    2012-01-01

    Background. Studies have documented that built environment factors potentially promote or impede leisure time physical activity (LTPA). This study explored the relationship between multiple built environment factors and individual characteristics on LTPA. Methods. Multiple data sources were utilized including individual level data for health behaviors and health status from the Nevada Behavioral Risk Factor Surveillance System (BRFSS) and community level data from different data sources including indicators for recreation facilities, safety, air quality, commute time, urbanization, population density, and land mix level. Mixed model logistic regression and geographic information system (GIS) spatial analysis were conducted. Results. Among 6,311 respondents, 24.4% reported no LTPA engagement during the past 30 days. No engagement in LTPA was significantly associated with (1) individual factors: older age, less education, lower income, being obesity, and low life satisfaction and (2) community factors: more commute time, higher crime rate, urban residence, higher population density, but not for density and distance to recreation facilities, air quality, and land mix. Conclusions. Multiple data systems including complex population survey and spatial analysis are valuable tools on health and built environment studies.

  4. Anode gas recirculation for improving the performance and cost of a 5-kW solid oxide fuel cell system

    NASA Astrophysics Data System (ADS)

    Torii, Ryohei; Tachikawa, Yuya; Sasaki, Kazunari; Ito, Kohei

    2016-09-01

    Solid oxide fuel cells (SOFCs) have the potential to efficiently convert chemical energy into electricity and heat and are expected to be implemented in stationary combined heat and power (CHP) systems. This paper presents the heat balance analysis for a 5-kW medium-sized integrated SOFC system and the evaluation of the effect of anode gas recirculation on the system performance. The risk of carbon deposition on an SOFC anode due to anode gas recirculation is also assessed using the C-H-O diagram obtained from thermodynamic equilibrium calculations. These results suggest that a higher recirculation ratio increases net fuel utilization and improves the electrical efficiency of the SOFC system. Furthermore, cost simulation of the SOFC system and comparison with the cost of electricity supply by a power grid indicates that the capital cost is sufficiently low to popularize the SOFC system in terms of the total cost over one decade.

  5. Volatile organic compound and particulate emission studies of AF (Air Force) paint-booth facilities. Phase 1. Final report, February-December 1987

    SciTech Connect

    Ayer, J.; Wolbach, D.

    1988-07-01

    This study presents the results of volatile organic compound (VOC) and particulate emission surveys performed at three Air Force painting facilities. The three facilities -- one in McClellan AFB buildings 655 and two at Travis AFB in buildings 550 and 1014 -- did not meet local VOC emission standards. The possibility of reducing these emissions with recirculation modifications and various VOC reduction and control strategies is discussed. Although VOC emissions from paint spray booths can be controlled by add-on control systems, control is expensive for present air flow rates. The use of air recirculation within the spray booth can reduce the cost of VOC emission controls by reducing the quantity of air that requires processing. Recirculation systems were designed for two of the painting facilities included in this study. In designing the systems, various criteria such as paint booth VOC concentrations and health and safety standards were considered. Add-on VOC emission-control systems that can be used in conjunction with the recirculation system are evaluated. The devices of interest are a solvent incineration system and an activated-carbon adsorption bed. The VOC removal efficiency, initial capital investment and operating costs for both of these technologies are discussed.

  6. Conceptual design of the cryogenic system and estimation of the recirculated power for CFETR

    NASA Astrophysics Data System (ADS)

    Liu, Xiaogang; Qiu, Lilong; Li, Junjun; Wang, Zhaoliang; Ren, Yong; Wang, Xianwei; Li, Guoqiang; Gao, Xiang; Bi, Yanfang

    2017-01-01

    The China Fusion Engineering Test Reactor (CFETR) is the next tokamak in China’s roadmap for realizing commercial fusion energy. The CFETR cryogenic system is crucial to creating and maintaining operational conditions for its superconducting magnet system and thermal shields. The preliminary conceptual design of the CFETR cryogenic system has been carried out with reference to that of ITER. It will provide an average capacity of 75 to 80 kW at 4.5 K and a peak capacity of 1300 kW at 80 K. The electric power consumption of the cryogenic system is estimated to be 24 MW, and the gross building area is about 7000 m2. The relationships among the auxiliary power consumed by the cryogenic system, the fusion power gain and the recirculated power of CFETR are discussed, with the suggestion that about 52% of the electric power produced by CFETR in phase II must be recirculated to run the fusion test reactor.

  7. Tritium Superpermeability: Experimental Investigation and Simulation of Tritium Recirculation in 'Prometheus' Setup

    SciTech Connect

    Musyaev, R.K.; Lebedev, B.S.; Grishechkin, S.K.; Yukhimchuk, A.A.; Busnyuk, A.A; Notkin, M.E.; Samartsev, A.A.; Livshits, A.I.

    2005-07-15

    The superpermeability phenomenon was suggested to use in fusion machines to separate the fuel mixture from helium ashes, to arrange in-vessel fuel recirculation contours and effective evacuation of fuel mixture out of machine exhaust. To develop this technology and to simulate tritium recirculation in RFNC-VNIIEF at the 'Prometheus' setup the experiments on superpermeation of hydrogen isotopes through metal membrane were realized.The results of experiments on superpermeation of hydrogen isotopes through cylindrical niobium membrane are presented. As the experiment has shown, membrane pumping rate is inversely proportional to square root of isotope mass and amount to 2.5 l/cm{sup 2}s for protium, 1.8 l/cm{sup 2}s for deuterium and 1.5 l/cm{sup 2}s for tritium. The possibility of effective pumping, separation of hydrogen isotopes from helium and residual gas, compression and recuperation of hydrogen isotopes by means of superpermeable membrane was demonstrated. It follows from results that the separation of D/T from He with employment of the techniques of superpermeable membranes might reduce the total amount of tritium in fuel cycle and substantially enhance the resource of cryogenic pumps evacuating helium.

  8. Recirculation zones induce non-Fickian transport in three-dimensional periodic porous media

    NASA Astrophysics Data System (ADS)

    Crevacore, Eleonora; Tosco, Tiziana; Sethi, Rajandrea; Boccardo, Gianluca; Marchisio, Daniele L.

    2016-11-01

    In this work, the influence of pore space geometry on solute transport in porous media is investigated performing computational fluid dynamics pore-scale simulations of fluid flow and solute transport. The three-dimensional periodic domains are obtained from three different pore structure configurations, namely, face-centered-cubic (fcc), body-centered-cubic (bcc), and sphere-in-cube (sic) arrangements of spherical grains. Although transport simulations are performed with media having the same grain size and the same porosity (in fcc and bcc configurations), the resulting breakthrough curves present noteworthy differences, such as enhanced tailing. The cause of such differences is ascribed to the presence of recirculation zones, even at low Reynolds numbers. Various methods to readily identify recirculation zones and quantify their magnitude using pore-scale data are proposed. The information gained from this analysis is then used to define macroscale models able to provide an appropriate description of the observed anomalous transport. A mass transfer model is applied to estimate relevant macroscale parameters (hydrodynamic dispersion above all) and their spatial variation in the medium; a functional relation describing the spatial variation of such macroscale parameters is then proposed.

  9. Nitrification in brackish water recirculating aquaculture system integrated with activated packed bed bioreactor.

    PubMed

    Rejish Kumar, V J; Joseph, Valsamma; Philip, Rosamma; Bright Singh, I S

    2010-01-01

    Recirculation aquaculture systems (RAS) depend on nitrifying biofilters for the maintenance of water quality, increased biosecurity and environmental sustainability. To satisfy these requirements a packed bed bioreactor (PBBR) activated with indigenous nitrifying bacterial consortia has been developed and commercialized for operation under different salinities for instant nitrification in shrimp and prawn hatchery systems. In the present study the nitrification efficiency of the bioreactor was tested in a laboratory level recirculating aquaculture system for the rearing of Penaeus monodon for a period of two months under higher feeding rates and no water exchange. Rapid setting up of nitrification was observed during the operation, as the volumetric total ammonia nitrogen removal rates (VTR) increased with total ammonia nitrogen (TAN) production in the system. The average Volumetric TAN Removal Rates (VTR) at the feeding rate of 160 g/day from 54-60th days of culture was 0.1533+/-0.0045 kg TAN/m(3)/day. The regression between VTR and TAN explained 86% variability in VTR (P<0.001). The laboratory level RAS demonstrated here showed high performance both in terms of shrimp biomass yield and nitrification and environmental quality maintenance. Fluorescent in-situ Hybridization analysis of the reactor biofilm ensured the presence of autotrophic nitrifier groups such as Nitrosococcus mobilis lineage, Nitrobacter spp and phylum Nitrospira, the constituent members present in the original consortia used for activating the reactors. This showed the stability of the consortia on long term operation.

  10. Developments of Optical Resonators and Optical Recirculators for Compton X/γ Ray Machines

    NASA Astrophysics Data System (ADS)

    Martens, A.; , Mightylaser, Thomx Collaboration; Eurogammas Association

    2015-10-01

    Optical resonators and optical recirculators are key elements of Compton X/γ ray machines. With regard to their use in laser physics or in time-frequency metrology, these devices have to obey severe constraints when implemented in the vaccum of an electron accelerator. Our group has developed both types of devices. In this proceedings an original recirculator design, that was developed within the European proposal to the ELI-NP γ ray source call for tender, is described. This is an aberration free device which allows reciculating 32 times a short and high intensity laser pulse. It also allows synchronizing each of the 32 passes with the electron RF cavities within 100 fs. The second topic of these proceedings is a description of our R & D on optical resonators dedicated to laser-electron interactions. We have locked two different picosecond laser oscillators to the highest cavity finesse F=30000 ever reached in pulsed regime. We also designed and build a new kind of non-planar cavity, tetrahedron shape, providing circularly polarized eigen modes. This cavity was installed in the ATF accelerator of KEK and successfully used to produce a high gamma ray flux. Thanks to an original fibre amplifier, we succeed in stacking 100 kW of average power inside the cavity.

  11. Viability of the vascularly perfused, recirculating rat intestine and intestine-liver preparations

    SciTech Connect

    Hirayama, H.; Xu, X.; Pang, K.S. )

    1989-08-01

    Function and stability of vascularly perfused, recirculating in situ rat intestine (I) and intestine-liver (IL) preparations were evaluated in fasted and nonfasted rats because these techniques may be readily applied in drug metabolism studies. The rat intestine was perfused with blood medium (7.5 ml/min) via the superior mesenteric artery, with the venous outflow draining into the portal vein, which, together with hepatic arterial flow (2.5 ml/min), constituted the total blood flow (10 ml/min) to the liver. Maintenance of intestinal membrane integrity was observed. Rapid ({sup 14}C)glucose absorption against a concentration gradient and a lack of ({sup 3}H)-polyethylene glycol 4000 (PEG 4000, less than 4%) and Evans blue absorption by the recirculating I and IL preparations resulted after bolus injections of these markers into the pyloric end of the duodenum. Other indexes that revealed stable intestinal and liver functions were the following: preservation of reservoir perfusate volume, constancy in perfusion pressure, bile flow, and hemoglobin concentrations, evidence of intestinal glucose utilization and liver glucose production, and a lack of significant leakage of serum glutamic oxalic transaminase. The intestine and liver consumed oxygen at relatively constant rates, but the consumption rates for the fasted tissues (I or L) were significantly higher than those for nonfasted tissues. These results indicate that the vascularly perfused I and IL preparations were maintained in a viable and stable state for a 2-h perfusion period.

  12. Convection-Enhanced Biopatterning with Recirculation of Hydrodynamically Confined Nanoliter Volumes of Reagents.

    PubMed

    Autebert, Julien; Cors, Julien F; Taylor, David P; Kaigala, Govind V

    2016-03-15

    We present a new methodology for efficient and high-quality patterning of biological reagents for surface-based biological assays. The method relies on hydrodynamically confined nanoliter volumes of reagents to interact with the substrate at the micrometer-length scale. We study the interplay between diffusion, advection, and surface chemistry and present the design of a noncontact scanning microfluidic device to efficiently present reagents on surfaces. By leveraging convective flows, recirculation, and mixing of a processing liquid, this device overcomes limitations of existing biopatterning approaches, such as passive diffusion of analytes, uncontrolled wetting, and drying artifacts. We demonstrate the deposition of analytes, showing a 2- to 5-fold increase in deposition rate together with a 10-fold reduction in analyte consumption while ensuring less than 6% variation in pattern homogeneity on a standard biological substrate. In addition, we demonstrate the recirculation of a processing liquid using a microfluidic probe (MFP) in the context of a surface assay for (i) probing 12 independent areas with a single microliter of processing liquid and (ii) processing a 2 mm(2) surface to create 170 antibody spots of 50 × 100 μm(2) area using 1.6 μL of liquid. We observe high pattern quality, conservative usage of reagents, micrometer precision of localization and convection-enhanced fast deposition. Such a device and method may facilitate quantitative biological assays and spur the development of the next generation of protein microarrays.

  13. Recirculation zones induce non-Fickian transport in three-dimensional periodic porous media.

    PubMed

    Crevacore, Eleonora; Tosco, Tiziana; Sethi, Rajandrea; Boccardo, Gianluca; Marchisio, Daniele L

    2016-11-01

    In this work, the influence of pore space geometry on solute transport in porous media is investigated performing computational fluid dynamics pore-scale simulations of fluid flow and solute transport. The three-dimensional periodic domains are obtained from three different pore structure configurations, namely, face-centered-cubic (fcc), body-centered-cubic (bcc), and sphere-in-cube (sic) arrangements of spherical grains. Although transport simulations are performed with media having the same grain size and the same porosity (in fcc and bcc configurations), the resulting breakthrough curves present noteworthy differences, such as enhanced tailing. The cause of such differences is ascribed to the presence of recirculation zones, even at low Reynolds numbers. Various methods to readily identify recirculation zones and quantify their magnitude using pore-scale data are proposed. The information gained from this analysis is then used to define macroscale models able to provide an appropriate description of the observed anomalous transport. A mass transfer model is applied to estimate relevant macroscale parameters (hydrodynamic dispersion above all) and their spatial variation in the medium; a functional relation describing the spatial variation of such macroscale parameters is then proposed.

  14. 2-Methylisoborneol and geosmin uptake by organic sludge derived from a recirculating aquaculture system.

    PubMed

    Guttman, Lior; van Rijn, Jaap

    2009-02-01

    In a previous study on a recirculating fish culture system, levels of geosmin and 2-methylisoborneol were found to decrease when culture water was recirculated through the anaerobic sludge digestion treatment stage of the system. This finding led us to the present study in which the geosmin and 2-methylisoborneol removal capacity of the sludge derived from this treatment stage was examined in vitro. It was found that reduction of off-flavor compounds by the sludge was mediated by both chemical/physical sorption and biological degradation. At geosmin and 2-methylisoborneol concentrations within the range of those experienced in fish culture systems, chemical/physical sorption by the sludge was found to account for a 93% reduction in geosmin and a 79% reduction in 2-methylisoborneol from the overlying water within 48h of incubation. Combined with the biological degradation taking place in the sludge, a complete removal of these compounds from the water phase occurred within 9 days of incubation. By means of repeated washing of the geosmin and 2-methylisoborneol contaminate sludge with clean water, relatively small amounts of these compounds were released from the sludge, a possible indication for the fact that absorption, rather than adsorption, underlies the chemical/physical removal process.

  15. Design and Simulation of the Recirculating Crossed-Field Planar Amplifier

    NASA Astrophysics Data System (ADS)

    Exelby, Steven; Greening, Geoffrey; Jordan, Nicholas; Simon, David; Lau, Yue Ying; Gilgenbach, Ronald; Hoff, Brad

    2016-10-01

    The Recirculating Planar Crossed-Field Amplifier (RPCFA) is a high power microwave device adapted from the Recirculating Planar Magnetron1, developed at the University of Michigan. A travelling-wave, rectangular, meander-line design has been developed in simulation that amplifies a 1.3 MW signal at 3 GHz to approximately 29 MW (13.5 dB) with nearly 53% electronic efficiency. Simulation also shows that the RPCFA is zero-drive stable, e.g., output of any appreciable power is dependent on the presence of an input RF signal. The amplifier was designed to be driven by the Michigan Electron Long Beam Accelerator (MELBA), which is currently configured to deliver a -300 kV, 1-10 kA, 0.3-1.0 µs pulse. Taking these parameters into consideration, a slow wave structure, cathode, and housing were designed using the finite element frequency domain code Ansys HFSS. The cold tube characteristics and RF field structures were then verified using the particle in cell code, MAGIC. Hot tube simulations on MAGIC were also run to calculate the RPCFA's performance, including gain and efficiency. Future work will include building a prototype RPCFA, cold testing, and performing experiments to verify the hot tube simulations. This work was supported by the AFOSR Grant FA9550-15-1-0097.

  16. Convection-Enhanced Biopatterning with Recirculation of Hydrodynamically Confined Nanoliter Volumes of Reagents

    PubMed Central

    2016-01-01

    We present a new methodology for efficient and high-quality patterning of biological reagents for surface-based biological assays. The method relies on hydrodynamically confined nanoliter volumes of reagents to interact with the substrate at the micrometer-length scale. We study the interplay between diffusion, advection, and surface chemistry and present the design of a noncontact scanning microfluidic device to efficiently present reagents on surfaces. By leveraging convective flows, recirculation, and mixing of a processing liquid, this device overcomes limitations of existing biopatterning approaches, such as passive diffusion of analytes, uncontrolled wetting, and drying artifacts. We demonstrate the deposition of analytes, showing a 2- to 5-fold increase in deposition rate together with a 10-fold reduction in analyte consumption while ensuring less than 6% variation in pattern homogeneity on a standard biological substrate. In addition, we demonstrate the recirculation of a processing liquid using a microfluidic probe (MFP) in the context of a surface assay for (i) probing 12 independent areas with a single microliter of processing liquid and (ii) processing a 2 mm2 surface to create 170 antibody spots of 50 × 100 μm2 area using 1.6 μL of liquid. We observe high pattern quality, conservative usage of reagents, micrometer precision of localization and convection-enhanced fast deposition. Such a device and method may facilitate quantitative biological assays and spur the development of the next generation of protein microarrays. PMID:26837532

  17. The impact of compaction and leachate recirculation on waste degradation in simulated landfills.

    PubMed

    Ko, Jae Hac; Yang, Fan; Xu, Qiyong

    2016-07-01

    This study investigated the impact of compaction and leachate recirculation on anaerobic degradation of municipal solid waste (MSW) at different methane formation phases. Two stainless steel lysimeters, C1 and C2, were constructed by equipping a hydraulic cylinder to apply pressure load (42kPs) on the MSW. When MSW started to produce methane, C1 was compacted, but C2 was compacted when the methane production rate declined from the peak generation rate. Methane production of C1was inhibited by the compaction and resulted in producing a total of 106L methane (44L/kgVS). However, the compaction in C2 promoted MSW degradation resulting in producing a total of 298L methane (125L/kgVS). The concentrations of volatile fatty acids and chemical oxygen demand showed temporary increases, when pressure load was applied. It was considered that the increased substrate accessibility within MSW by compaction could cause either the inhibition or the enhancement of methane production, depending the tolerability of methanogens on the acidic inhibition. Leachate recirculation also gave positive effects on methane generation from wet waste in the decelerated methanogenic phase by increasing mass transfer and the concentrations of volatile fatty acids.

  18. Investigation of sludge re-circulating clarifiers design and optimization through numerical simulation.

    PubMed

    Davari, S; Lichayee, M J

    2003-01-01

    In steam thermal power plants (TPP) with open re-circulating wet cooling towers, elimination of water hardness and suspended solids (SS) is performed in clarifiers. Most of these clarifiers are of high efficiency sludge re-circulating type (SRC) with capacity between 500-1,500 m3/hr. Improper design and/or mal-operation of clarifiers in TPPs results in working conditions below design capacity or production of soft water with improper quality (hardness and S.S.). This causes accumulation of deposits in heat exchangers, condenser tubes, cooling and service water pipes and boiler tubes as well as increasing the ionic load of water at the demineralizing system inlet. It also increases the amount of chemical consumptions and produces more liquid and solid waste. In this regard, a software program for optimal design and simulation of SRCs has been developed. Then design parameters of existing SRCs in four TPPs in Iran were used as inputs to developed software program and resulting technical specifications were compared with existing ones. In some cases improper design was the main cause of poor outlet water quality. In order to achieve proper efficiency, further investigations were made to obtain control parameters as well as design parameters for both mal-designed and/or mal-operated SRCs.

  19. Effect of flue gas recirculation on heat transfer in a supercritical circulating fluidized bed combustor

    NASA Astrophysics Data System (ADS)

    Błaszczuk, Artur

    2015-09-01

    This paper focuses on assessment of the effect of flue gas recirculation (FGR) on heat transfer behavior in 1296t/h supercritical coal-fired circulating fluidized bed (CFB) combustor. The performance test in supercritical CFB combustor with capacity 966 MWth was performed with the low level of flue gas recirculation rate 6.9% into furnace chamber, for 80% unit load at the bed pressure of 7.7 kPa and the ratio of secondary air to the primary air SA/PA = 0.33. Heat transfer behavior in a supercritical CFB furnace between the active heat transfer surfaces (membrane wall and superheater) and bed material has been analyzed for Geldart B particle with Sauter mean diameters of 0.219 and 0.246 mm. Bed material used in the heat transfer experiments had particle density of 2700 kg/m3. A mechanistic heat transfer model based on cluster renewal approach was used in this work. A heat transfer analysis of CFB combustion system with detailed consideration of bed-to-wall heat transfer coefficient distributions along furnace height is investigated. Heat transfer data for FGR test were compared with the data obtained for representative conditions without recycled flue gases back to the furnace through star-up burners.

  20. Progress and Challenges in Developing Reference Data Layers for Human Population Distribution and Built Infrastructure

    NASA Astrophysics Data System (ADS)

    Chen, R. S.; Yetman, G.; de Sherbinin, A. M.

    2015-12-01

    Understanding the interactions between environmental and human systems, and in particular supporting the applications of Earth science data and knowledge in place-based decision making, requires systematic assessment of the distribution and dynamics of human population and the built human infrastructure in conjunction with environmental variability and change. The NASA Socioeconomic Data and Applications Center (SEDAC) operated by the Center for International Earth Science Information Network (CIESIN) at Columbia University has had a long track record in developing reference data layers for human population and settlements and is expanding its efforts on topics such as intercity roads, reservoirs and dams, and energy infrastructure. SEDAC has set as a strategic priority the acquisition, development, and dissemination of data resources derived from remote sensing and socioeconomic data on urban land use change, including temporally and spatially disaggregated data on urban change and rates of change, the built infrastructure, and critical facilities. We report here on a range of past and ongoing activities, including the Global Human Settlements Layer effort led by the European Commission's Joint Research Centre (JRC), the Global Exposure Database for the Global Earthquake Model (GED4GEM) project, the Global Roads Open Access Data Working Group (gROADS) of the Committee on Data for Science and Technology (CODATA), and recent work with ImageCat, Inc. to improve estimates of the exposure and fragility of buildings, road and rail infrastructure, and other facilities with respect to selected natural hazards. New efforts such as the proposed Global Human Settlement indicators initiative of the Group on Earth Observations (GEO) could help fill critical gaps and link potential reference data layers with user needs. We highlight key sectors and themes that require further attention, and the many significant challenges that remain in developing comprehensive, high quality

  1. Characterization of Mycobacterium salmoniphilum as causal agent of mycobacteriosis in Atlantic salmon, Salmo salar L., from a freshwater recirculation system.

    PubMed

    Aro, L; Correa, K; Martínez, A; Ildefonso, R; Yáñez, J M

    2014-04-01

    Thirty Atlantic salmon, Salmo salar L., with low corporal condition relative to other fish present in the culture system, were sampled from a freshwater recirculation pisciculture located in Chile. The most characteristic signs and lesions were cachexia and presence of multiple greyish-white granulomas within internal organs. The external and internal lesions, along with the microscopic, histologic and biochemical findings, were consistent with mycobacteriosis. The identification of Mycobacterium salmoniphilum as the causal agent of the lesions was possible through the use of molecular analyses. This study represents the first report of Mycobacterium salmoniphilum in a freshwater recirculation system and the first case of fish mycobacteriosis described in Chile.

  2. The NASA integrated test facility and its impact on flight research

    NASA Technical Reports Server (NTRS)

    Mackall, D. A.; Pickett, M. D.; Schilling, L. J.; Wagner, C. A.

    1988-01-01

    The Integrated Test Facility (ITF), being built at NASA Ames-Dryden Flight Research Facility, will provide new test capabilities for emerging research aircraft. An overview of the ITF and the challenges being addressed by this unique facility are outlined. The current ITF capabilities, being developed with the X-29 Forward Swept Wing Program, are discussed along with future ITF activities.

  3. Configuration and Management of a Cluster Computing Facility in Undergraduate Student Computer Laboratories

    ERIC Educational Resources Information Center

    Cornforth, David; Atkinson, John; Spennemann, Dirk H. R.

    2006-01-01

    Purpose: Many researchers require access to computer facilities beyond those offered by desktop workstations. Traditionally, these are offered either through partnerships, to share the cost of supercomputing facilities, or through purpose-built cluster facilities. However, funds are not always available to satisfy either of these options, and…

  4. Simulation of air quality and cost to ventilate swine farrowing facilities in winter

    PubMed Central

    Park, Jae Hong; Peters, Thomas M.; Altmaier, Ralph; Sawvel, Russell A.; Anthony, T. Renée

    2016-01-01

    We developed a simulation model to study the effect of ventilation airflow rate with and without filtered recirculation on airborne contaminant concentrations (dust, NH3, CO, and CO2) for swine farrowing facilities. Energy and mass balance equations were used to simulate the indoor air quality and operational cost for a variety of ventilation conditions over a 3-month winter period, using time-varied outdoor temperature. The sensitivity of input and output parameters on indoor air quality and operational cost were evaluated. Significant factors affecting model output included mean winter temperature, generation rate of contaminants, pit-air-exchange ratio, and recirculation ratio. As mean outdoor temperature was decreased from −2.5 °C to −12.5 °C, total operational costs were increased from $872 to $1304. Dust generation rate affected dust concentrations linearly. When dust generation rates changed −50% and +100% from baseline, indoor dust concentrations were changed −50% and +100%, respectively. The selection of a pit-air-exchange ratio was found critical to NH3 concentration, but has little impact on other contaminants or cost. As the pit-air-exchange ratio was increased from 0.1 to 0.3, the NH3 concentration was increased by a factor of 1.5. The recirculation ratio affected both IAQ factors and total operational cost. As the recirculation ratio decreased to 0, inhalable and respirable dust concentrations, humidity, NH3 and CO2 concentrations decreased and total operational cost ($2216) was 104% more than with pit-fan-only ventilation ($1088). When the recirculation ratio was 1, the total operational cost was increased by $573 (53%) compared to pit-fan-only. Simulation provides a useful tool for examining the costs and benefits to installing common ventilation technology to CAFO and, ultimately, making sound management decisions. PMID:26937062

  5. Simulation of air quality and cost to ventilate swine farrowing facilities in winter.

    PubMed

    Park, Jae Hong; Peters, Thomas M; Altmaier, Ralph; Sawvel, Russell A; Anthony, T Renée

    2013-10-01

    We developed a simulation model to study the effect of ventilation airflow rate with and without filtered recirculation on airborne contaminant concentrations (dust, NH3, CO, and CO2) for swine farrowing facilities. Energy and mass balance equations were used to simulate the indoor air quality and operational cost for a variety of ventilation conditions over a 3-month winter period, using time-varied outdoor temperature. The sensitivity of input and output parameters on indoor air quality and operational cost were evaluated. Significant factors affecting model output included mean winter temperature, generation rate of contaminants, pit-air-exchange ratio, and recirculation ratio. As mean outdoor temperature was decreased from -2.5 °C to -12.5 °C, total operational costs were increased from $872 to $1304. Dust generation rate affected dust concentrations linearly. When dust generation rates changed -50% and +100% from baseline, indoor dust concentrations were changed -50% and +100%, respectively. The selection of a pit-air-exchange ratio was found critical to NH3 concentration, but has little impact on other contaminants or cost. As the pit-air-exchange ratio was increased from 0.1 to 0.3, the NH3 concentration was increased by a factor of 1.5. The recirculation ratio affected both IAQ factors and total operational cost. As the recirculation ratio decreased to 0, inhalable and respirable dust concentrations, humidity, NH3 and CO2 concentrations decreased and total operational cost ($2216) was 104% more than with pit-fan-only ventilation ($1088). When the recirculation ratio was 1, the total operational cost was increased by $573 (53%) compared to pit-fan-only. Simulation provides a useful tool for examining the costs and benefits to installing common ventilation technology to CAFO and, ultimately, making sound management decisions.

  6. The Built Environment and Active Travel: Evidence from Nanjing, China

    PubMed Central

    Feng, Jianxi

    2016-01-01

    Background: An established relationship exists between the built environment and active travel. Nevertheless, the literature examining the impacts of different components of the built environment is limited. In addition, most existing studies are based on data from cities in the U.S. and Western Europe. The situation in Chinese cities remains largely unknown. Based on data from Nanjing, China, this study explicitly examines the influences of two components of the built environment—the neighborhood form and street form—on residents’ active travel. Methods: Binary logistic regression analyses examined the effects of the neighborhood form and street form on subsistence, maintenance and discretionary travel, respectively. For each travel purpose, three models are explored: a model with only socio-demographics, a model with variables of the neighborhood form and a complete model with all variables. Results: The model fit indicator, Nagelkerke’s ρ2, increased by 0.024 when neighborhood form variables are included and increased by 0.070 when street form variables are taken into account. A similar situation can be found in the models of maintenance activities and discretionary activities. Regarding specific variables, very limited significant impacts of the neighborhood form variables are observed, while almost all of the characteristics of the street form show significant influences on active transport. Conclusions: In Nanjing, street form factors have a more profound influence on active travel than neighborhood form factors. The focal point of the land use regulations and policy of local governments should shift from the neighborhood form to the street form to maximize the effects of policy interventions. PMID:27005645

  7. Assessing Built Environment Walkability using Activity-Space Summary Measures

    PubMed Central

    Tribby, Calvin P.; Miller, Harvey J.; Brown, Barbara B.; Werner, Carol M.; Smith, Ken R.

    2015-01-01

    There is increasing emphasis on active transportation, such as walking, in transportation planning as a sustainable form of mobility and in public health as a means of achieving recommended physical activity and better health outcomes. A research focus is the influence of the built environment on walking, with the ultimate goal of identifying environmental modifications that invite more walking. However, assessments of the built environment for walkability are typically at a spatially disaggregate level (such as street blocks) or at a spatially aggregate level (such as census block groups). A key issue is determining the spatial units for walkability measures so that they reflect potential walking behavior. This paper develops methods for assessing walkability within individual activity spaces: the geographic region accessible to an individual during a given walking trip. We first estimate street network-based activity spaces using the shortest path between known trip starting/ending points and a travel time budget that reflects potential alternative paths. Based on objective walkability measures of the street blocks, we use three summary measures for walkability within activity spaces: i) the average walkability score across block segments (representing the general level of walkability in the activity space); ii) the standard deviation (representing the walkability variation), and; iii) the network autocorrelation (representing the spatial coherence of the walkability pattern). We assess the method using data from an empirical study of built environment walkability and walking behavior in Salt Lake City, Utah, USA. We visualize and map these activity space summary measures to compare walkability among individuals’ trips within their neighborhoods. We also compare summary measures for activity spaces versus census block groups, with the result that they agree less than half of the time. PMID:27213027

  8. Strengthening the weak link: Built Environment modelling for loss analysis

    NASA Astrophysics Data System (ADS)

    Millinship, I.

    2012-04-01

    Methods to analyse insured losses from a range of natural perils, including pricing by primary insurers and catastrophe modelling by reinsurers, typically lack sufficient exposure information. Understanding the hazard intensity in terms of spatial severity and frequency is only the first step towards quantifying the risk of a catastrophic event. For any given event we need to know: Are any structures affected? What type of buildings are they? How much damaged occurred? How much will the repairs cost? To achieve this, detailed exposure information is required to assess the likely damage and to effectively calculate the resultant loss. Modelling exposures in the Built Environment therefore plays as important a role in understanding re/insurance risk as characterising the physical hazard. Across both primary insurance books and aggregated reinsurance portfolios, the location of a property (a risk) and its monetary value is typically known. Exactly what that risk is in terms of detailed property descriptors including structure type and rebuild cost - and therefore its vulnerability to loss - is often omitted. This data deficiency is a primary source of variations between modelled losses and the actual claims value. Built Environment models are therefore required at a high resolution to describe building attributes that relate vulnerability to property damage. However, national-scale household-level datasets are often not computationally practical in catastrophe models and data must be aggregated. In order to provide more accurate risk analysis, we have developed and applied a methodology for Built Environment modelling for incorporation into a range of re/insurance applications, including operational models for different international regions and different perils and covering residential, commercial and industry exposures. Illustrated examples are presented, including exposure modelling suitable for aggregated reinsurance analysis for the UK and bespoke high resolution

  9. Design considerations for healthcare simulation facilities.

    PubMed

    Seropian, Michael; Lavey, Robert

    2010-12-01

    The number of simulation facilities across the United States and internationally is growing rapidly. The capital investment required can be substantive regardless of size. This article focuses on ways to optimize expenditures and maximize utility. Several key factors will play decisive roles in the successful launch of a new simulation facility. Mission/vision, budget, functional need, and space are partners in determining the final design of the simulation facility. Ideally, the budget is based on the functional requirements and desired capacity; but when this is not the case, of course, the owner must prioritize the needs of the new center. The type of space allocated for the facility is also critical and can seriously impact the budget because renovating a space that is fitted for another purpose versus constructing the center in an open shell space can add considerable cost. A well-balanced design team led by a diligent and knowledgeable project manager who can keep the team focused is integral to the success of designing and constructing a new facility. Users should inform themselves about each of the issues that a design team may consider to ensure that the issues are resolved in a way that meets the needs and vision of the program(s). A simulation facility, such as any education facility, should be built around the concepts of the overall mission, vision, and values of the institution(s) and stakeholder(s). For any new educational facility to be a success, the thoughts, ideas, and creativity of the owner, users, and stakeholders must find its way into the ultimate built environment. The experience base of simulation facility design is fragmented and not standardized. Therefore, we live at a time where the risk of ineffective design is higher than one would like given the costs involved. It behooves the owner to set parameters with the planning and design team that they want a balanced, controlled, collaborative, and inclusive design process.

  10. 66. The Thornton Block was built in 1900 at 65 ...

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

    66. The Thornton Block was built in 1900 at 65 East Broadway. It has a cast-iron and glass canopy over the first floor entrance on the south side. F. Augustus Heinze, the copper magnate, was a long-term resident of Thornton's Hotel. It was remodeled in 1947 by the Anaconda Copper Mining Employees Club, but much of the interior detail--woodwork, door trims, etc.--remains. The exterior has not been substantially altered. - Butte Historic District, Bounded by Copper, Arizona, Mercury & Continental Streets, Butte, Silver Bow County, MT

  11. Approaching direct optimization of as-built lens performance

    NASA Astrophysics Data System (ADS)

    McGuire, James P.; Kuper, Thomas G.

    2012-10-01

    We describe a method approaching direct optimization of the rms wavefront error of a lens including tolerances. By including the effect of tolerances in the error function, the designer can choose to improve the as-built performance with a fixed set of tolerances and/or reduce the cost of production lenses with looser tolerances. The method relies on the speed of differential tolerance analysis and has recently become practical due to the combination of continuing increases in computer hardware speed and multiple core processing We illustrate the method's use on a Cooke triplet, a double Gauss, and two plastic mobile phone camera lenses.

  12. 53. Shiner's Furniture (75 East Park) was built in 1892 ...

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

    53. Shiner's Furniture (75 East Park) was built in 1892 and housed a restaurant, two storefronts, and lodgings. The facade, of brick and rough quarry stone, is divided visually by having the western portion extend one story higher than the eastern. Designs for the cornices and top stones are also different. The east portion has a pediment; the western a three-bay apex. The first floor has a modern plate-glass storefront with metal canopy. - Butte Historic District, Bounded by Copper, Arizona, Mercury & Continental Streets, Butte, Silver Bow County, MT

  13. Built-In-Test Equipment Requirements Workshop. Workshop Presentation

    DTIC Science & Technology

    1981-08-01

    If that is : ’. , recognized, development of the diagnostic system with its BIT ! support should be the same kind of process as require d to get...distribution unlimited, i. I, "I: UNCLASSIFIED SECURITY CLASSIFICATION OF T,5S PAGE tw%"I Date £nm.. d ) ___________________ I READ INSTRUCTIONS REPORT...NO0TES 19. Key wORDS (Co.,ltnue on ,c.,ea" e 1yee1 aid* itRC0s an8 t tir by bWac* AI~a.AW Built-in-Test (BI~T), 100 Percent Diagnostics , diagnostic

  14. 70. The Miners Union Local #1 was built at 125 ...

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

    70. The Miners Union Local #1 was built at 125 West Granite in 1906 to house the Silver Bow Club, an exclusive Butte businessmen's club. The building was designed by Link and Haire, Architects. The Club sold the building in the 1940s. The foundation has steel beams laid in the concrete footings, and the basement level is of sandstone. Marble, hardwood and stained glass remain as interior finishes. - Butte Historic District, Bounded by Copper, Arizona, Mercury & Continental Streets, Butte, Silver Bow County, MT

  15. Making microbiology of the built environment relevant to design.

    PubMed

    Brown, G Z; Kline, Jeff; Mhuireach, Gwynne; Northcutt, Dale; Stenson, Jason

    2016-02-16

    Architects are enthusiastic about "bioinformed design" as occupant well-being is a primary measure of architectural success. However, architects are also under mounting pressure to create more sustainable buildings. Scientists have a critical opportunity to make the emerging field of microbiology of the built environment more relevant and applicable to real-world design problems by addressing health and sustainability in tandem. Practice-based research, which complements evidence-based design, represents a promising approach to advancing knowledge of the indoor microbiome and translating it to architectural practice.

  16. Downgrading Nuclear Facilities to Radiological Facilities

    SciTech Connect

    Jarry, Jeffrey F.; Farr, Jesse Oscar; Duran, Leroy

    2015-08-01

    Based on inventory reductions and the use of alternate storage facilities, the Sandia National Laboratories (SNL) downgraded 4 SNL Hazard Category 3 (HC-3) nuclear facilities to less-than-HC-3 radiological facilities. SNL’s Waste Management and Pollution Prevention Department (WMPPD) managed the HC-3 nuclear facilities and implemented the downgrade. This paper will examine the downgrade process,

  17. The NASA Lewis Research Center Water Tunnel Facility

    NASA Technical Reports Server (NTRS)

    Wasserbauer, Charles A.

    1997-01-01

    A water tunnel facility specifically designed to investigate internal fluid duct flows has been built at the NASA Research Center. It is built in a modular fashion so that a variety of internal flow test hardware can be installed in the facility with minimal facility reconfiguration. The facility and test hardware interfaces are discussed along with design constraints for future test hardware. The inlet chamber flow conditioning approach is also detailed. Instrumentation and data acquisition capabilities are discussed. The incoming flow quality has been documented for about one quarter of the current facility operating range. At that range, there is some scatter in the data in the turbulent boundary layer which approaches 10 percent of the duct radius leading to a uniform core.

  18. Environmental assessments in the built environment: crucial yet underdeveloped

    NASA Astrophysics Data System (ADS)

    Heinonen, Jukka; Horvath, Arpad; Junnila, Seppo

    2015-03-01

    Environmental assessments have been developed with increasing emphasis since the wide-scale emergence of environmental concerns in the 1970s. However, after decades there is still plenty of room left for development. These assessments are also rapidly becoming more and more crucial as we seem to be reaching the boundaries of the carrying capacity of our planet. Assessments of the emissions from the built environment and especially of the interactions between human communities and emissions are in a very central role in the quest to solve the great problem of sustainable living. Policy- makers and professionals in various fields urgently need reliable data on the current conditions and realistic future projections, as well as robust and scientifically defensible models for decision making. This recognition was the main motivation to call for this Focus Issue, and the published contributions truly highlight the same point. This editorial provides brief summaries and discussions on the 16 articles of the Focus Issue, depicting the several interesting perspectives they offer to advance the state of the art. Now we encourage academics, practitioners, government, industry, individual consumers, and other decision makers to utilize the available findings and develop the domain of environmental assessment of the built environment further. Indeed, we hope that this Focus Issue is merely a kernel of a significantly large future body of literature.

  19. Conceptual framework describing a child's total (built, natural ...

    EPA Pesticide Factsheets

    The complexity of the components and their interactions that characterize children’s health and well-being are not adequately captured by current public health paradigms. Children are exposed to combinations of chemical and non-chemical stressors from their built, natural, and social environments at each lifestage and throughout their lifecourse. Children’s inherent characteristics (e.g., sex, genetics, pre-existing disease) and their activities and behaviors also influence their exposures to chemical and non-chemical stressors from these environments. We describe a conceptual framework that considers the interrelationships between inherent characteristics, activities and behaviors, and stressors (both chemical and non-chemical) from the built, natural, and social environments in influencing children’s health and well-being throughout their lifecourse. This framework is comprised of several intersecting circles that represent how stressors from the total environment interact with children’s inherent characteristics and their activities and behaviors to influence their health and well-being at each lifestage and throughout their lifecourse. We used this framework to examine the complex interrelationships between chemical and non-chemical stressors for two public health challenges specific to children: childhood obesity and general cognitive ability. One systematic scoping review showed that children’s general cognitive ability was influenced not only by

  20. Fireball multi object spectrograph: as-built optic performances

    NASA Astrophysics Data System (ADS)

    Grange, R.; Milliard, B.; Lemaitre, G.; Quiret, S.; Pascal, S.; Origné, A.; Hamden, E.; Schiminovich, D.

    2016-07-01

    Fireball (Faint Intergalactic Redshifted Emission Balloon) is a NASA/CNES balloon-borne experiment to study the faint diffuse circumgalactic medium from the line emissions in the ultraviolet (200 nm) above 37 km flight altitude. Fireball relies on a Multi Object Spectrograph (MOS) that takes full advantage of the new high QE, low noise 13 μm pixels UV EMCCD. The MOS is fed by a 1 meter diameter parabola with an extended field (1000 arcmin2) using a highly aspherized two mirror corrector. All the optical train is working at F/2.5 to maintain a high signal to noise ratio. The spectrograph (R 2200 and 1.5 arcsec FWHM) is based on two identical Schmidt systems acting as collimator and camera sharing a 2400 g/mm aspherized reflective Schmidt grating. This grating is manufactured from active optics methods by double replication technique of a metal deformable matrix whose active clear aperture is built-in to a rigid elliptical contour. The payload and gondola are presently under integration at LAM. We will present the alignment procedure and the as-built optic performances of the Fireball instrument.

  1. Sources of airborne microorganisms in the built environment.

    PubMed

    Prussin, Aaron J; Marr, Linsey C

    2015-12-22

    Each day people are exposed to millions of bioaerosols, including whole microorganisms, which can have both beneficial and detrimental effects. The next chapter in understanding the airborne microbiome of the built environment is characterizing the various sources of airborne microorganisms and the relative contribution of each. We have identified the following eight major categories of sources of airborne bacteria, viruses, and fungi in the built environment: humans; pets; plants; plumbing systems; heating, ventilation, and air-conditioning systems; mold; dust resuspension; and the outdoor environment. Certain species are associated with certain sources, but the full potential of source characterization and source apportionment has not yet been realized. Ideally, future studies will quantify detailed emission rates of microorganisms from each source and will identify the relative contribution of each source to the indoor air microbiome. This information could then be used to probe fundamental relationships between specific sources and human health, to design interventions to improve building health and human health, or even to provide evidence for forensic investigations.

  2. Evaluation of a Shaker Dust Collector for Use in a Recirculating Ventilation System.

    PubMed

    Peters, Thomas M; Sawvel, Russell A; Park, Jae Hong; Anthony, T Renée

    2015-01-01

    General ventilation with recirculated air may be cost-effective to control the concentration of low-toxicity, contaminants in workplaces with diffuse, dusty operations, such as in agriculture. Such systems are, however, rarely adopted with little evidence showing improved air quality and ability to operate under harsh conditions. The goal of this work was to examine the initial and long-term performance of a fabric-filter shaker dust collector (SDC) in laboratory tests and as deployed within a recirculating ventilation system in an agricultural building. In laboratory tests, collection efficiency and pressure drop were tracked over several filter loading cycles, and the recovery of filter capacity (pressure drop) from filter shaking was examined. Collection efficiencies of particles larger than 5 μm was high (>95%) even when the filter was pristine, showing effective collection of large particles that dominate inhalable concentrations typical of agricultural dusts. For respirable-sized particles, collection efficiencies were low when the filter was pristine (e.g., 27% for 1 μm) but much higher when a dust cake developed on the filter (>99% for all size particles), even after shaking (e.g., 90% for 1 μm). The first shake of a filter was observed to recovery a substantial fraction of filter capacity, with subsequent shakes providing little benefit. In field tests, the SDC performed effectively over a period of three months in winter when incorporated in a recirculating ventilation system of a swine farrowing room. Trends in collection efficiency and pressure drop with loading were similar to those observed in the laboratory with overall collection efficiencies high (>80%) when pressure drop exceeded 230 Pa, or 23% of the maximum loading recommended by the manufacturer. This work shows that the SDC can function effectively over the harsh winter in swine rearing operations. Together with findings of improved air quality in the farrowing room reported in a

  3. Evaluation of a Shaker Dust Collector for Use in a Recirculating Ventilation System

    PubMed Central

    Sawvel, Russell A.; Park, Jae Hong; Anthony, T. Renée

    2016-01-01

    General ventilation with recirculated air may be cost-effective to control the concentration of low-toxicity, contaminants in workplaces with diffuse, dusty operations, such as in agriculture. Such systems are, however, rarely adopted with little evidence showing improved air quality and ability to operate under harsh conditions. The goal of this work was to examine the initial and long-term performance of a fabric-filter shaker dust collector (SDC) in laboratory tests and as deployed within a recirculating ventilation system in an agricultural building. In laboratory tests, collection efficiency and pressure drop were tracked over several filter loading cycles, and the recovery of filter capacity (pressure drop) from filter shaking was examined. Collection efficiencies of particles larger than 5 μm was high (>95%) even when the filter was pristine, showing effective collection of large particles that dominate inhalable concentrations typical of agricultural dusts. For respirable-sized particles, collection efficiencies were low when the filter was pristine (e.g., 27% for 1 μm) but much higher when a dust cake developed on the filter (>99% for all size particles), even after shaking (e.g., 90% for 1 μm). The first shake of a filter was observed to recovery a substantial fraction of filter capacity, with subsequent shakes providing little benefit. In field tests, the SDC performed effectively over a period of three months in winter when incorporated in a recirculating ventilation system of a swine farrowing room. Trends in collection efficiency and pressure drop with loading were similar to those observed in the laboratory with overall collection efficiencies high (>80%) when pressure drop exceeded 230 Pa, or 23% of the maximum loading recommended by the manufacturer. This work shows that the SDC can function effectively over the harsh winter in swine rearing operations. Together with findings of improved air quality in the farrowing room reported in a companion

  4. Transition and acoustic response of recirculation structures in an unconfined co-axial isothermal swirling flow

    NASA Astrophysics Data System (ADS)

    Santhosh, R.; Miglani, Ankur; Basu, Saptarshi

    2013-08-01

    This paper reports the first observations of transition from a pre-vortex breakdown (Pre-VB) flow reversal to a fully developed central toroidal recirculation zone in a non-reacting, double-concentric swirling jet configuration and its response to longitudinal acoustic excitation. This transition proceeds with the formation of two intermediate, critical flow regimes. First, a partially penetrated vortex breakdown bubble (VBB) is formed that indicates the first occurrence of an enclosed structure as the centre jet penetration is suppressed by the growing outer roll-up eddy; resulting in an opposed flow stagnation region. Second, a metastable transition structure is formed that marks the collapse of inner mixing vortices. In this study, the time-averaged topological changes in the coherent recirculation structures are discussed based on the non-dimensional modified Rossby number (Rom) which appears to describe the spreading of the zone of swirl influence in different flow regimes. Further, the time-mean global acoustic response of pre-VB and VBB is measured as a function of pulsing frequency using the relative aerodynamic blockage factor (i.e., maximum radial width of the inner recirculation zone). It is observed that all flow modes except VBB are structurally unstable as they exhibit severe transverse radial shrinkage (˜20%) at the burner Helmholtz resonant modes (100-110 Hz). In contrast, all flow regimes show positional instability as seen by the large-scale, asymmetric spatial shifting of the vortex core centres. Finally, the mixing transfer function M (f) and magnitude squared coherence λ2(f) analysis is presented to determine the natural coupling modes of the system dynamic parameters (u', p'), i.e., local acoustic response. It is seen that the pre-VB flow mode exhibits a narrow-band, low pass filter behavior with a linear response window of 100-105 Hz. However, in the VBB structure, presence of critical regions such as the opposed flow stagnation region

  5. 26 CFR 1.1374-3 - Net unrealized built-in gain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 11 2012-04-01 2012-04-01 false Net unrealized built-in gain. 1.1374-3 Section... Net unrealized built-in gain. (a) In general. An S corporation's net unrealized built-in gain is the... net unrealized built-in gain—(1) In general. If section 1374(d)(8) applies to an S...

  6. Beam dynamics activities at the Thomas Jefferson National Accelerator Facility (Jefferson Lab)

    SciTech Connect

    Douglas, D.R.

    1997-12-01

    The Thomas Jefferson National Accelerator Facility (Jefferson Lab) has been funded by the US Navy to build an infra-red FEL driven by an energy-recovering compact SRF-based linear accelerator. The machine is to produce a 1 kW IR photon beam. The Jefferson Lab Accelerator Division is presently engaged in detailed design and beam dynamics studies for the driver accelerator. Principle beam dynamics and beam transport considerations include: (1) generation and transport of a high-quality, high-current, space-charge dominated beam; (2) the impact of coherent synchrotron radiation (CSR) during beam recirculation transport; (3) low-loss transport of a large momentum spread, high-current beam; (4) beam break up (BBU) instabilities in the recirculating accelerator; (5) impedance policing of transport system components; and (6) RF drive system control during energy recovery and FEL operation.

  7. End-to-end 9-D polarized bunch transport in eRHIC energy-recovery recirculator, some aspects

    SciTech Connect

    Meot, F.; Meot, F.; Brooks, S.; Ptitsyn, V.; Trbojevic, D.; Tsoupas, N.

    2015-05-03

    This paper is a brief overview of some of the numerous beam and spin dynamics investigations undertaken in the framework of the design of the FFAG based electron energy recovery re-circulator ring of the eRHIC electron-ion collider project

  8. Stocking density effects on production characteristics and body composition of market size cobia, Rachycentron canadum, reared in recirculating aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production density in excess of a critical threshold can result in a negative relationship between stocking density and fish production. This study was conducted to evaluate production characteristics of juvenile cobia Rachycentron canadum, reared to market size in production-scale recirculating aq...

  9. Production characteristics and body composition of juvenile cobia fed three different commercial diets in recirculating aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of feeding three commercial diets on production characteristics and body composition of juvenile cobia Rachycentron canadum reared using recirculating aquaculture systems (RAS) was evaluated in a 56 d growth trial. Juvenile cobia (29.2 +/= 0.7 g, mean weight +/= SE) were stocked into thr...

  10. Evaluation of a low-head recirculating aquaculture system used for rearing Florida pompano to market size

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A low-head recirculating aquaculture system (RAS) was evaluated for the production Florida pompano Trachinotus carolinus from juvenile to market size. The RAS consisted of three dual-drain, 3-m diameter culture tanks of 7.8 m3 volume each, two 0.7-m3 moving bed bioreactors filled 67% with K1 kaldnes...

  11. Effects of organic loading rate and effluent recirculation on the performance of two-stage anaerobic digestion of vegetable waste.

    PubMed

    Zuo, Zhuang; Wu, Shubiao; Zhang, Wanqin; Dong, Renjie

    2013-10-01

    The effects of organic loading rates (OLR) and effluent recirculation on dynamics of acidogenic and methanogenic processes in two-stage anaerobic digestion of vegetable waste were investigated. Two systems were performed at OLRs of 1.3, 1.7, 2.1 and 2.6 g VS/L/d. One system recirculated the effluent from the methanogenic reactor to acidogenic reactor. With increasing OLRs, total volatile fatty acid (VFA) concentration increased to approximately 8500 mg/L in acidogenic digester, where pH decreased from 6.4 to 5.2. Daily biogas production and methane content in methanogenic reactor increased from 1.2 to 4.4 L/d and from 27.4% to 60.5%, respectively. However, inhibition of hydrolysis in acidogenic reactor was demonstrated under the OLR of 2.6 g VS/L/d without recirculation, thus indicating system overloading. Effluent recirculation shown a considerable positive effect on alleviating VFA inhibition and improving biogas production in acidogenic reactor because of the effect of dilution and pH adjustment, particularly at high OLRs.

  12. A study of NO{sub x} reduction by fuel injection recirculation. Topical report, June--December, 1995

    SciTech Connect

    Turns, S.R.; Feese, J.J.

    1996-01-01

    Flue-gas recirculation (FGR) is a well-known method used to control oxides of nitrogen (NO{sub x}) in industrial burner applications. Recent small- and large-scale experiments have shown that introducing the recirculated flue gases with the fuel results in a much greater reduction in NO{sub x}, per unit mass of gas recirculated, in comparison to introducing the flue gases with the combustion air. That fuel injection recirculation (FIR) is more effective than windbox FGR is quite remarkable. At present, however, there is no definitive understanding of why FIR is more effective than conventional FGR. The objective of this research is to ascertain whether or not chemical and/or molecular transport effects alone can explain the differences in NO{sub x} reduction observed between FIR and FGR. This knowledge will aid in the rational application and optimization of FIR in a wide variety of industrial applications. A combined modeling and experimental program is in progress to achieve the research objectives. This report discusses, first, computer modeling studies of counterflow diffusion flames employing detailed chemical kinetics for methane combustion and NO{sub x} formation, and, second, experimental studies of laminar, CH{sub 4}-air, jet flames.

  13. Production characteristics of Florida pompano reared to market size at two different densities in low salinity recirculating aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Florida pompano Trachinotus carolinus, a high-value carangid, is widely recognized as an excellent candidate for commercial mariculture. While results of a recent study indicated that pompano can be successfully reared to market size in small scale recirculating aquaculture systems (RAS) at low...

  14. The impact of water exchange rate on the health and performance of rainbow trout Oncorhynchus mykiss in recirculation aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fish mortality in recirculating aquaculture systems (RAS) has been observed by the authors to increase when RAS are managed at low makeup water exchange rates with relatively high feed loading. The precise etiology of this elevated mortality was unknown, all typical water quality parameters were wit...

  15. Preparatory work required for a long-term district recirculation test in a gassy underground metal-non metal mine

    SciTech Connect

    Pritchard, C.J.

    1995-12-31

    Federal mine safety regulations prohibit the recirculation of face air In a gassy Class III metal-non metal mine. Tg Soda Ash, Inc, operates a 2.0M ton/yr (2.2 million st/yr) underground gassy Class III trona mine in southwest Wyoming, currently liberating approximately 5,700 m{sup 3}/day (200,000 ft{sup 3}/day) of methane. Because of the low methane emissions and the incombustibility of trona, it was decided that Tg would be an excellent environment to test recirculation at a U.S. gassy mine, for possible future use by industry. A research program was begun with the cooperation of MSHA, the U.S. Bureau of Mines, the University of Utah, and Tg. Initial testing centered around re-using shop air underground. Next, conduct a continuous miner section recirculation test to see how the face contamination was affected by 305m (1,000 ft) and 610m (2,000 ft) recirculation distances. A district test followed to examine the effects of the critical parameter - respirable dust. Finally, a long-term program to study respirable trona dust transportation and deposition In mine airways to plan for district fan siting and effects on face air dust levels.

  16. The effects of carbon dioxide on performance and histopathology of rainbow trout Oncorhynchus mykiss in water recirculation aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chronic exposure to elevated levels of dissolved carbon dioxide (CO2) has been linked to reduced growth, physiological disturbances and negative health outcomes in intensively reared fish. Although pumping to a degassing tower can lower concentrations of dissolved CO2 in water recirculation aquacult...

  17. The effect of aeration and recirculation on a sand-based hybrid constructed wetland treating low-strength domestic wastewater.

    PubMed

    Zapater-Pereyra, M; Kyomukama, E; Namakula, V; van Bruggen, J J A; Lens, P N L

    2016-08-01

    The Duplex-constructed wetland (CW) is a hybrid system composed of a vertical flow (VF) CW on top of a horizontal flow filter (HFF). Each compartment is designed to play a different role: aerobic treatment in the VF CW due to intermittent feeding and anoxic treatment in the HFF due to saturated conditions. Three Duplex-CWs were used in this study: Control, Aerated and Recirculating. The role of each compartment was tested for pollutant removal and micro-invertebrate abundance. In all systems, the VF CW removed mainly organic matter, solids and NH4(+)-N. Pathogens were removed in both compartments. Likewise, total nitrogen removal occurred in both compartments, only the Recirculating HFF was not able to denitrify the nitrogen due to the slightly more oxic conditions as compared to the other systems. All systems met discharge guidelines for organic matter, but only the Control and Aerated systems met those for total nitrogen. At the applied loading rates, the pollutant removal was not significantly enhanced by the use of aeration and recirculation. Therefore, operation as in the Control system, without aeration or recirculation, is recommended for the tested Duplex-CWs. If artificial aeration will be used in CWs, the support material should be carefully selected to allow a proper air distribution.

  18. Preliminary studies on the depuration of common off-flavors from fish raised in recirculating aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    “Off-flavor” problems can adversely impact the growth of the aquaculture industry. Fish raised in recirculating systems have the potential to develop the common off-flavors “earthy” and “musty” due to accumulation of the microbial metabolites geosmin and 2-methylisoborneol (MIB) in the fish flesh. ...

  19. Performance of a Water Recirculation Loop Maintenance Device and Process for the Advanced Spacesuit Water Membrane Evaporator

    NASA Technical Reports Server (NTRS)

    Rector, Tony; Steele, John W.; Bue, Grant C.; Campbell, Colin; Makinen, Janice

    2012-01-01

    A water loop maintenance device and process to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been undergoing a performance evaluation. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the water recirculation maintenance device and process is to further enhance this advantage through the leveraging of fluid loop management lessons-learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance process further leverages a sorbent developed for ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware. This

  20. Design and Evaluation of a Water Recirculation Loop Maintenance Device for the Advanced Spacesuit Water Membrane Evaporator

    NASA Technical Reports Server (NTRS)

    Steele, John W.; Rector, Tony; Bue, Grant C.; Campbell, Colin; Makinen, Janice

    2011-01-01

    A dual-bed device to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been designed and is undergoing testing. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the development of a water recirculation maintenance device is to further enhance this advantage through the leveraging of fluid loop management lessons-learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The bed design further leverages a sorbent developed for ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a clear demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.