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Sample records for active fluid bed

  1. Fluid bed material transfer method

    DOEpatents

    Pinske, Jr., Edward E.

    1994-01-01

    A fluidized bed apparatus comprising a pair of separated fluid bed enclosures, each enclosing a fluid bed carried on an air distributor plate supplied with fluidizing air from below the plate. At least one equalizing duct extending through sidewalls of both fluid bed enclosures and flexibly engaged therewith to communicate the fluid beds with each other. The equalizing duct being surrounded by insulation which is in turn encased by an outer duct having expansion means and being fixed between the sidewalls of the fluid bed enclosures.

  2. Field evaluation of a granular activated carbon fluid-bed bioreactor for treatment of chlorobenzene in groundwater

    SciTech Connect

    Klecka, G.M.; McDaniel, S.G.; Wilson, P.S.

    1996-12-31

    Although granular activated carbon (GAC), fluidized-bed bioreactors have been used for treatment of groundwater containing readily biodegradable organic compounds, there is only limited experience with treatment of chlorinated organics found at many industrial sites. This paper describes a field evaluation of a GAC fluid-bed bioreactor operated at various chlorobenzene concentrations and organic loading rates over a 7-month period. Microorganisms used to seed the bioreactor were provided by activated sludge form the site, as well as indigenous chlorobenzene-degrading bacteria present in the groundwater. Removal efficiencies exceeding 99.99% were achieved at organic loading rates between 6 and 10 pounds of total oxygen demand (lb TOD) per 25 cubic feet per day. Influent chlorobenzene concentrations ranging form 100 to 170 ppm were consistently reduced to below the detection limit of 10 ppb. Economic evaluation indicates that groundwater treatment costs for the bioreactor were lower than other conventional technologies. 44 refs., 9 figs., 5 tabs.

  3. Fluid bed solids heater. Final technical report

    SciTech Connect

    Preuit, L. C.

    1980-01-01

    A solids heater which operates at up to 2000 F was designed, fabricated, installed and operated through checkout at the Morgantown Energy Technology Center at Morgantown, West Virginia. The system, designated the 2000 F Fluid Bed Solids Heater (FBSH) uses a fluidized bed to heat limestone to 600 F and aluminium oxide or silicon carbide to 2000 F and discharges heated solids upon demand. The FBSH with added valve handling and pressurization equipment is known as the Valve Hot Solids Test Unit and is intended for use by the US Department of Energy for testing of valves for severe service applications in coal conversion and utilization processes. The FBSH as designed and supplied by Combustion Power Company includes process equipment, controls, the enclosing building and other associated equipment. In the 600 F range of operation it can circulate limestone through two valve test trains simultaneously on a continuous basis. Only one valve test train is used for 2000 F solids and operation in that range is also continuous. Limestone, crushed to minus 5/16 size, is heated, discharged, and recycled at a maximum average rate of 250 lb/min while aluminum oxide or silicon carbide, No. 8 grit, is circulated at rates up to 167 lb/min. The FBSH control system is designed for automatic operation, and capability is included for external computerized data acquisition and/or supervisory control. An operating and maintenance manual and as-built drawings have been submitted. This report describes the FBSH equipment, its design basis, and its operation. It has been prepared and submitted in fulfillment of Contract Number DIAC05-77ET10499.

  4. Evaluation of fluid bed heat exchanger optimization parameters. Final report

    SciTech Connect

    Not Available

    1980-03-01

    Uncertainty in the relationship of specific bed material properties to gas-side heat transfer in fluidized beds has inhibited the search for optimum bed materials and has led to over-conservative assumptions in the design of fluid bed heat exchangers. An experimental program was carried out to isolate the effects of particle density, thermal conductivity, and heat capacitance upon fluid bed heat transfer. A total of 31 tests were run with 18 different bed material loads on 12 material types; particle size variations were tested on several material types. The conceptual design of a fluidized bed evaporator unit was completed for a diesel exhaust heat recovery system. The evaporator heat transfer surface area was substantially reduced while the physical dimensions of the unit increased. Despite the overall increase in unit size, the overall cost was reduced. A study of relative economics associated with bed material selection was conducted. For the fluidized bed evaporator, it was found that zircon sand was the best choice among materials tested in this program, and that the selection of bed material substantially influences the overall system costs. The optimized fluid bed heat exchanger has an estimated cost 19% below a fin augmented tubular heat exchanger; 31% below a commercial design fluid bed heat exchanger; and 50% below a conventional plain tube heat exchanger. The comparisons being made for a 9.6 x 10/sup 6/ Btu/h waste heat boiler. The fluidized bed approach potentially has other advantages such as resistance to fouling. It is recommended that a study be conducted to develop a systematic selection of bed materials for fluidized bed heat exchanger applications, based upon findings of the study reported herein.

  5. Granular activated carbon adsorption and fluid-bed reactivation at Manchester, New Hampshire. Final report Mar 77-Apr 82

    SciTech Connect

    Kittredge, D.; Beaurivage, R.; Paris, D.

    1983-10-01

    Treatment performances of virgin and reactivated GAC were evaluated during three reactivation-exhaustion cycles by measuring total organic carbon (TOC), trihalomethanes (THM), and trihalomethane formation potential (THMFP). GAC adsorptive capacity was measured using traditional test parameters including iodine number, molasses decolorizing index, BET, and pore-size distribution. The GAC was reactivated on-site by a 500 lb/hr fluidized-bed unit. Results of this study demonstrated that onsite reactivation was a cost-effective method of restoring the adsorptive properties of spent GAC. During a 10-month period, more than 1.8 million lb of GAC was reactivated at a total cost of less than 22 cents/lb as compared with a delivered cost of 61.5 cents/lb for virgin GAC. The average total carbon loss resulting from transportation and reactivation was 11.5% by volume.

  6. Effectiveness of an anaerobic granular activated carbon fluidized-bed bioreactor to treat soil wash fluids: a proposed strategy for remediating PCP/PAH contaminated soils.

    PubMed

    Koran, K M; Suidan, M T; Khodadoust, A P; Sorial, G A; Brenner, R C

    2001-07-01

    An integrated system has been developed to remediate soils contaminated with pentachlorophenol (PCP) and polycyclic aromatic hydrocarbons (PAHs). This system involves the coupling of two treatment technologies, soil-solvent washing and anaerobic biotreatment of the extract. Specifically, this study evaluated the effectiveness of a granular activated carbon (GAC) fluidized-bed reactor to treat a synthetic-waste stream of PCP and four PAHs (naphthalene, acenaphthene, pyrene, and benzo(b)fluoranthene) under anaerobic conditions. This waste stream was intended to simulate the wash fluids from a soil washing process treating soils from a wood-preserving site. The reactor achieved a removal efficiency of greater than 99.8% for PCP with conversion to its dechlorination intermediates averaging 46.5%. Effluent, carbon extraction, and isotherm data also indicate that naphthalene and acenaphthene were removed from the liquid phase with efficiencies of 86 and 93%, respectively. Effluent levels of pyrene and benzo(b)fluoranthene were extremely low due to the high-adsorptive capacity of GAC for these compounds. Experimental evidence does not suggest that the latter two compounds were biochemically transformed within the reactor.

  7. Fluid-bed air-supply system

    DOEpatents

    Atabay, Keramettin

    1979-01-01

    The air-supply system for a fluidized-bed furnace includes two air conduits for the same combustion zone. The conduits feed separate sets of holes in a distributor plate through which fluidizing air flows to reach the bed. During normal operation, only one conduit and set of holes is used, but the second conduit and set of holes is employed during start-up.

  8. Shielded fluid stream injector for particle bed reactor

    SciTech Connect

    Notestein, J.E.

    1991-12-31

    A shielded fluid-stream injector assembly is provided for particle bed reactors. The assembly includes a perforated pipe injector disposed across the particle bed region of the reactor and an inverted V-shaped shield placed over the pipe, overlapping it to prevent descending particles from coming into direct contact with the pipe. The pipe and shield are fixedly secured at one end to the reactor wall and slidably secured at the other end to compensate for thermal expansion. An axially extending housing aligned with the pipe and outside the reactor and an inline reamer are provided for removing deposits from the inside of the pipe. The assembly enables fluid streams to be injected and distributed uniformly into the particle bed with minimized clogging of injector ports. The same design may also be used for extraction of fluid streams from particle bed reactors.

  9. Shielded fluid stream injector for particle bed reactor

    DOEpatents

    Notestein, John E.

    1993-01-01

    A shielded fluid-stream injector assembly is provided for particle bed reactors. The assembly includes a perforated pipe injector disposed across the particle bed region of the reactor and an inverted V-shaped shield placed over the pipe, overlapping it to prevent descending particles from coming into direct contact with the pipe. The pipe and shield are fixedly secured at one end to the reactor wall and slidably secured at the other end to compensate for thermal expansion. An axially extending housing aligned with the pipe and outside the reactor and an in-line reamer are provided for removing deposits from the inside of the pipe. The assembly enables fluid streams to be injected and distributed uniformly into the particle bed with minimized clogging of injector ports. The same design may also be used for extraction of fluid streams from particle bed reactors.

  10. Fluid bed technology in materials processing

    SciTech Connect

    Gupta, C.K.; Sathiyamoorthy, D.

    1999-01-01

    The author explores the various aspects of fluidization engineering and examines its applications in a multitude of materials processing techniques. Topics include process metallurgy, fluidization in nuclear engineering, and the pros and cons of various fluidization equipment. Gupta emphasizes fluidization engineering in high temperature processing, and high temperature fluidized bed furnaces.

  11. Bed inventory overturn in a circulating fluid bed riser with pant-leg structure

    SciTech Connect

    Jinjing Li; Wei Wang; Hairui Yang; Junfu Lv; Guangxi Yue

    2009-05-15

    The special phenomenon, nominated as bed inventory overturn, in circulating fluid bed (CFB) riser with pant-leg structure was studied with model calculation and experimental work. A compounded pressure drop mathematic model was developed and validated with the experimental data in a cold experimental test rig. The model calculation results agree well with the measured data. In addition, the intensity of bed inventory overturn is directly proportional to the fluidizing velocity and is inversely proportional to the branch point height. The results in the present study provide significant information for the design and operation of a CFB boiler with pant-leg structure. 15 refs., 10 figs., 1 tab.

  12. Nitrate destruction in an elutriated fluid-bed calciner

    SciTech Connect

    Cowan, R.G.; Cash, R.J.; Owen, T.J.; Shook, G.E.

    1987-09-01

    Nitrate destruction was demonstrated using an elutriated fluid-bed calciner process developed for nuclear fuel mixed-oxide conversion. Testing was directed to treatment of sodium nitrate, a major waste component at the Hanford Site. One test was also performed with copper nitrate. All tests produced low concentrations of NO/sub x/ in the offgas. The chemistry developed for uranium and plutonium nitrate appears to apply to other metal nitrates. The copper nitrate test was successful, with over 90% of the nitrate converted to elemental nitrogen and water and with recovery of a granular, free-flowing copper product. Tests with sodium nitrate were not successful due to fusion of sodium carbonate in the calciner bed and plugging of the calciner. Further development of the elutriated fluid-bed system would be required to process high sodium nitrate waste solutions.

  13. Computational fluid dynamic modeling of fluidized-bed polymerization reactors

    SciTech Connect

    Rokkam, Ram

    2012-01-01

    Polyethylene is one of the most widely used plastics, and over 60 million tons are produced worldwide every year. Polyethylene is obtained by the catalytic polymerization of ethylene in gas and liquid phase reactors. The gas phase processes are more advantageous, and use fluidized-bed reactors for production of polyethylene. Since they operate so close to the melting point of the polymer, agglomeration is an operational concern in all slurry and gas polymerization processes. Electrostatics and hot spot formation are the main factors that contribute to agglomeration in gas-phase processes. Electrostatic charges in gas phase polymerization fluidized bed reactors are known to influence the bed hydrodynamics, particle elutriation, bubble size, bubble shape etc. Accumulation of electrostatic charges in the fluidized-bed can lead to operational issues. In this work a first-principles electrostatic model is developed and coupled with a multi-fluid computational fluid dynamic (CFD) model to understand the effect of electrostatics on the dynamics of a fluidized-bed. The multi-fluid CFD model for gas-particle flow is based on the kinetic theory of granular flows closures. The electrostatic model is developed based on a fixed, size-dependent charge for each type of particle (catalyst, polymer, polymer fines) phase. The combined CFD model is first verified using simple test cases, validated with experiments and applied to a pilot-scale polymerization fluidized-bed reactor. The CFD model reproduced qualitative trends in particle segregation and entrainment due to electrostatic charges observed in experiments. For the scale up of fluidized bed reactor, filtered models are developed and implemented on pilot scale reactor.

  14. Coal fired fluid bed module for a single elevation style fluid bed power plant

    DOEpatents

    Waryasz, Richard E.

    1979-01-01

    A fluidized bed for the burning of pulverized fuel having a specific waterwall arrangement that comprises a structurally reinforced framework of wall tubes. The wall tubes are reversely bent from opposite sides and then bonded together to form tie rods that extend across the bed to support the lateral walls thereof.

  15. Six years of ABB-CE, petcoke and fluid beds

    SciTech Connect

    Tanca, M.

    1994-12-31

    Combustion Engineering, Inc. (ABB-CE) has constructed twenty circulating fluidized bed (CFB) boilers and 2 bubbling fluidized bed (BFB) boilers throughout North America. The units were designed to fire a wide range of fuels from anthracite culm to coals, lignites and biomasses. Based on fuels economics, some plants have decided to use petroleum coke as a replacement or supplemental fuel. The fluid bed boiler can inherently handle a wide range of fuel types without requiring modification or down-rating. ABB-CE units have a significant amount of petroleum coke operating experience firing 100% petroleum coke with no supplemental fuel ranging from the first commercial CFB unit at New Brunswick Power to the largest CFB unit at Texas New Mexico Power. Petroleum coke is also being co-fired with anthracite culm at the Scott Paper CFB. The world`s largest operating BFB, the 160 MWe unit at TVA`s Shawnee plant, has also been co-firing petroleum coke. The ability of the fluidized bed technology to fire low volatile fuels such as petroleum cokes, efficiently and in an environmentally acceptable manner will result in the use of this technology as a preferred means of power generation. This report gives a brief description of the petroleum coke firing experiences with ABB-CE fluid bed steam generators over the last six years.

  16. Method for enhancing the desulfurization of hot coal gas in a fluid-bed coal gasifier

    DOEpatents

    Grindley, Thomas

    1989-01-01

    A process and apparatus for providing additional desulfurization of the hot gas produced in a fluid-bed coal gasifier, within the gasifier. A fluid-bed of iron oxide is located inside the gasifier above the gasification bed in a fluid-bed coal gasifier in which in-bed desulfurization by lime/limestone takes place. The product gases leave the gasification bed typically at 1600.degree. to 1800.degree. F. and are partially quenched with water to 1000.degree. to 1200.degree. F. before entering the iron oxide bed. The iron oxide bed provides additional desulfurization beyond that provided by the lime/limestone.

  17. Physiological responses to prolonged bed rest and fluid immersion in humans

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.

    1984-01-01

    For many centuries, physicians have used prolonged rest in bed and immersion in water in the treatment of ailments and disease. Both treatments have positive remedial effects. However, adverse physiological responses become evident when patients return to their normal daily activities. The present investigation is concerned with an analysis of the physiological changes during bed rest and the effects produced by water immersion. It is found that abrupt changes in body position related to bed rest cause acute changes in fluid compartment volumes. Attention is given to fluid shifts and body composition, renal function and diuresis, calcium and phosphorus metabolism, and orthostatic tolerance. In a discussion of water immersion, fluid shifts are considered along with cardiovascular-respiratory responses, renal function, and natriuretic and diuretic factors.

  18. Circulating fluid bed technology within Combustion Engineering Inc.

    SciTech Connect

    Treff, P.J.; Maitland, J.E.

    1995-12-31

    As the worldwide trend for more flexible, cost-effective CFB technology continues as an alternative to pulverized coal and combined cycle steam generation, Combustion Engineering Inc. has drawn on original scientific work and the operating history of numerous BFBs and CFBs worldwide as reported in publicly available literature to introduce many product enhancements for its next generation of circulating fluid bed boilers. The issues of in-furnace surface versus external fluid bed heat exchanger applicability, cyclone and loop seal design, refractory system design and operating requirements, and the suitability of regenerative air heaters for CFB applications will be among the topics discussed in this paper as Combustion Engineering Inc. answers the challenge to continuously advance CFB steam generation.

  19. An alternative circulating fluid bed bottom ash removal system

    SciTech Connect

    Barsin, J.A.; Carrea, A.

    1999-07-01

    Circulating fluid beds pose two challenges for the removal of spent or unreacted calcined limestone and coal ash from the bottom of the bed. The furnace operates under a positive pressure and thus a seal must be maintained between the ambient and the furnace and secondly the bottom ash is discharged at about 1600 F and must be cooled down before transported into a storage silo. In the higher bottom ash-loaded units (firing lignite or anthracite culm) this cooling represents a significant portion of the latent heat lost to the stream generator, thus affecting the overall heat rate. Also the material is abrasive traditionally which has had a negative effect upon the removal system life and maintenance costs. Now there is an alternative to the existing present water screw or auxiliary bed cooler systems applied in the past. This presentation reviews the successful application of a dry bottom ash removal system to pulverized coal (PC) fired units, the experimental and commercial scale developmental work to determine if that PC concept is applicable to Circulating Fluid Bed Units, and projected savings that might be realized if heat recovery, carbon recovery, reduction in parasitic power and maintenance costs all could be improved. The power generation industry typically demands at minimum a commercial demonstration of new technology prior to application and therefore a host site for dry bottom ash removal technology is sought.

  20. An alternative circulating fluid bed bottom ash removal system

    SciTech Connect

    Barsin, J.A.; Carrea, A.

    1999-11-01

    Circulating fluid beds pose two challenges for the removal of spent or unreacted calcined limestone and coal ash from the bottom of the bed. The furnace operates under a positive pressure and thus a seal must be maintained between the ambient and the furnace and secondly the bottom ash is discharged at about 1600 F and must be cooled down before transported into a storage silo. In the higher bottom ash-loaded units (firing lignite or anthracite culm) this cooling represents a significant portion of the latent heat lost to the steam generator, thus affecting the overall heat rate. Also the material is abrasive traditionally which has had a negative effect upon the removal system life and maintenance costs. Now there is an alternative to the existing present water screw or auxiliary bed cooler systems applied in the past. This presentation reviews the successful application of a dry bottom ash removal system to pulverized coal (PC) fired units, the experimental and commercial scale developmental work to determine if that PC concept is applicable to Circulating Fluid Bed Units, and projected savings that might be realized if heat recovery, carbon recovery, reduction in parasitic power and maintenance costs all could be improved. The power generation industry typically demands at minimum a commercial demonstration of new technology prior to application and therefore a host site for dry bottom ash removal technology is sought.

  1. Bed-rest studies: Fluid and electrolyte responses

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.

    1983-01-01

    Confinement in the horizontal position for 2 to 3 weeks results in a chronic decrease in plasma volume, increased interstitial fluid volume, and unchanged or slightly increased extracellular fluid volume. Concentrations of blood electrolytes, glucose, and nitrogenous constituents remain within normal limits of variability when maintenance levels of isometric or isotonic exercise are performed for 1 hr/day. Hematocrit and plasma osmolality can be elevated significantly throughout bed rest (BR). Significant diuresis occurs on the first day, and increases in urine Na and Ca continue throughout BR, although voluntary fluid intake is unchanged. Urine Na and K are evaluated during the second week of BR in spite of stabilization of PV and extracellular volume. The initial diuresis probably arises from the extracellular fluid while subsequent urine loss above control levels must come from the intracellular fluid. Preservation of the extracellular volume takes precedance over maintenance of the intracellular fluid volume. The functioning of a natriuretic factor (hormone) to account for the continued increased loss of Na in the urine is suggested.

  2. Bed-rest studies - Fluid and electrolyte responses

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.

    1983-01-01

    Confinement in the horizontal position for 2 to 3 weeks results in a chronic decrease in plasma volume, increased interstitial fluid volume, and unchanged or slightly increased extracellular fluid volume. Concentrations of blood electrolytes, glucose, and nitrogenous constituents remain within normal limits of variability when maintenance levels of isometric or isotonic exercise are performed for 1 hr/day. Hematocrit and plasma osmolality can be elevated significantly throughout bed rest (BR). Significant diuresis occurs on the first day, and increases in urine Na and Ca continue throughout BR, although voluntary fluid intake is unchanged. Urine Na and K are evaluated during the second week of BR in spite of stabilization of PV and extracellular volume. The initial diuresis probably arises from extracellular fluid while subsequent urine loss above control levels must come from the intracellular fluid. Preservation of the extracellular volume takes precedance over maintenance of the intracellular fluid volume. The functioning of a natriuretic factor (hormone) to account for the continued increased loss of Na in the urine is suggested. Previously announced in STAR as N83-24160

  3. Computational Fluid Dynamics Simulation of Fluidized Bed Polymerization Reactors

    SciTech Connect

    Fan, Rong

    2006-01-01

    Fluidized beds (FB) reactors are widely used in the polymerization industry due to their superior heat- and mass-transfer characteristics. Nevertheless, problems associated with local overheating of polymer particles and excessive agglomeration leading to FB reactors defluidization still persist and limit the range of operating temperatures that can be safely achieved in plant-scale reactors. Many people have been worked on the modeling of FB polymerization reactors, and quite a few models are available in the open literature, such as the well-mixed model developed by McAuley, Talbot, and Harris (1994), the constant bubble size model (Choi and Ray, 1985) and the heterogeneous three phase model (Fernandes and Lona, 2002). Most these research works focus on the kinetic aspects, but from industrial viewpoint, the behavior of FB reactors should be modeled by considering the particle and fluid dynamics in the reactor. Computational fluid dynamics (CFD) is a powerful tool for understanding the effect of fluid dynamics on chemical reactor performance. For single-phase flows, CFD models for turbulent reacting flows are now well understood and routinely applied to investigate complex flows with detailed chemistry. For multiphase flows, the state-of-the-art in CFD models is changing rapidly and it is now possible to predict reasonably well the flow characteristics of gas-solid FB reactors with mono-dispersed, non-cohesive solids. This thesis is organized into seven chapters. In Chapter 2, an overview of fluidized bed polymerization reactors is given, and a simplified two-site kinetic mechanism are discussed. Some basic theories used in our work are given in detail in Chapter 3. First, the governing equations and other constitutive equations for the multi-fluid model are summarized, and the kinetic theory for describing the solid stress tensor is discussed. The detailed derivation of DQMOM for the population balance equation is given as the second section. In this section

  4. Relationship between fluid bed aerosol generator operation and the aerosol produced

    SciTech Connect

    Carpenter, R.L.; Yerkes, K.

    1980-12-01

    The relationships between bed operation in a fluid bed aerosol generator and aerosol output were studied. A two-inch diameter fluid bed aerosol generator (FBG) was constructed using stainless steel powder as a fluidizing medium. Fly ash from coal combustion was aerosolized and the influence of FBG operating parameters on aerosol mass median aerodynamic diameter (MMAD), geometric standard deviation (sigma/sub g/) and concentration was examined. In an effort to extend observations on large fluid beds to small beds using fine bed particles, minimum fluidizing velocities and elutriation constant were computed. Although FBG minimum fluidizing velocity agreed well with calculations, FBG elutriation constant did not. The results of this study show that the properties of aerosols produced by a FBG depend on fluid bed height and air flow through the bed after the minimum fluidizing velocity is exceeded.

  5. Computational fluid dynamics analysis of aerosol deposition in pebble beds

    NASA Astrophysics Data System (ADS)

    Mkhosi, Margaret Msongi

    2007-12-01

    The Pebble Bed Modular Reactor is a high temperature gas cooled reactor which uses helium gas as a coolant. The reactor uses spherical graphite pebbles as fuel. The fuel design is inherently resistant to the release of the radioactive material up to high temperatures; therefore, the plant can withstand a broad spectrum of accidents with limited release of radionuclides to the environment. Despite safety features of the concepts, these reactors still contain large inventories of radioactive materials. The transport of most of the radioactive materials in an accident occurs in the form of aerosol particles. In this dissertation, the limits of applicability of existing computational fluid dynamics code FLUENT to the prediction of aerosol transport have been explored. The code was run using the Reynolds Averaged Navier-Stokes turbulence models to determine the effects of different turbulence models on the prediction of aerosol particle deposition. Analyses were performed for up to three unit cells in the orthorhombic configuration. For low flow conditions representing natural circulation driven flow, the laminar flow model was used and the results were compared with existing experimental data for packed beds. The results compares well with experimental data in the low flow regime. For conditions corresponding to normal operating of the reactor, analyses were performed using the standard k-ɛ turbulence model. From the inertial deposition results, a correlation that can be used to estimate the deposition of aerosol particles within pebble beds given inlet flow conditions has been developed. These results were converted into a dimensionless form as a function of a modified Stokes number. Based on results obtained in the laminar regime and for individual pebbles, the correlation developed for the inertial impaction component of deposition is believed to be credible. The form of the correlation developed also allows these results to be applied to pebble beds of different

  6. Experimental study of fluid dynamics in the pebble bed in a radial coolant flow

    NASA Astrophysics Data System (ADS)

    Smorchkova, Y. V.; Varava, A. N.; Dedov, A. V.; Komov, A. T.

    2016-10-01

    The results of experimental studies of pebble bed hydrodynamics are presented. For the first time experimental data on the pressure loss in a radial flow of fluid through the pebble bed was obtained. Experiments were carried out in the liquid flow rate ranging from 0.09 to 0.4 kg / s, fluid temperature is 20°C.

  7. Method and apparatus for enhancing the desulfurization of hot coal gas in a fluid-bed coal gasifier

    DOEpatents

    Grindley, T.

    1988-04-05

    A process and apparatus for providing additional desulfurization of the hot gas produced in a fluid-bed coal gasifier, within the gasifier is described. A fluid-bed of iron oxide is located inside the gasifier above the gasification bed in a fluid-bed coal gasifier in which in-bed desulfurization by lime/limestone takes place. The product gases leave the gasification bed typically at 1600 to 1800 F and are partially quenched with water to 1000 to 1200 F before entering the iron oxide bed. The iron oxide bed provides additional desulfurization beyond that provided by the lime /limestone. 1 fig.

  8. METAL FILTERS FOR PRESSURIZED FLUID BED COMBUSTION (PFBC) APPLICATIONS

    SciTech Connect

    M.A. Alvin

    2004-01-02

    Advanced coal and biomass-based gas turbine power generation technologies (IGCC, PFBC, PCFBC, and Hipps) are currently under development and demonstration. Efforts at the Siemens Westinghouse Power Corporation (SWPC) have been focused on the development and demonstration of hot gas filter systems as an enabling technology for power generation. As part of the demonstration effort, SWPC has been actively involved in the development of advanced filter materials and component configuration, has participated in numerous surveillance programs characterizing the material properties and microstructure of field-tested filter elements, and has undertaken extended, accelerated filter life testing programs. This report reviews SWPC's material and component assessment efforts, identifying the performance, stability, and life of porous commercial metal, advanced alloy, and intermetallic filters under simulated, pressurized fluidized-bed combustion (PFBC) conditions.

  9. Effect of dietary sodium on fluid/electrolyte regulation during bed rest

    NASA Technical Reports Server (NTRS)

    Williams, W. Jon; Schneider, Suzanne M.; Gretebeck, Randall J.; Lane, Helen W.; Stuart, Charles A.; Whitson, Peggy A.

    2003-01-01

    BACKGROUND: A negative fluid balance during bed rest (BR) is accompanied by decreased plasma volume (PV) which contributes to cardiovascular deconditioning. HYPOTHESIS: We hypothesized that increasing dietary sodium while controlling fluid intake would increase plasma osmolality (POSM), stimulate fluid conserving hormones, and reduce fluid/electrolyte (F/E) losses during BR; conversely, decreasing dietary sodium would decrease POSM, suppress fluid conserving hormones, and increase F/E losses. METHODS: We controlled fluid intake (30 ml x kg(-1) x d(-1)) in 17 men who consumed either a 4.0 +/- 0.06 g x d(-1) (174 mmol x d(-1)) (CONT; n = 6), 1.0 +/- 0.02 g x d(-1) (43 mmol x d(-1)) (LS; n = 6), or 10.0 +/- 0.04 g x d(-1) (430 mmol x d(-1)) (HS; n = 5) sodium diet before, during, and after 21 d of 6 degrees head-down BR. PV, total body water, urine volume and osmolality, POSM, and F/E controlling hormone concentrations were measured. RESULTS: In HS subjects, plasma renin activity (-92%), plasma/urinary aldosterone (-59%; -64%), and PV (-15.0%; 6.0 ml x kg(-1); p < 0.05) decreased while plasma atrial natriuretic peptide (+34%) and urine antidiuretic hormone (+24%) increased during BR (p < 0.05) compared with CONT. In LS, plasma renin activity (+166%), plasma aldosterone (+167%), plasma antidiuretic hormone (+19%), and urinary aldosterone (+335%) increased with no change in PV compared with CONT (p < 0.05). Total body water did not change in any of the subjects. CONCLUSIONS: Contrary to our hypothesis, increasing dietary sodium while controlling fluid intake during BR resulted in a greater loss of PV compared with the CONT subjects. Reducing dietary sodium while controlling fluid intake did not alter the PV response during BR compared with CONT subjects.

  10. Use of a polishing scrubber with a fluid bed boiler

    SciTech Connect

    Toher, J.G.

    1996-12-31

    Once viewed as {open_quotes}competitive{close_quotes} technologies, the circulating dry scrubber (CDS){reg_sign} and circulating fluid bed (CFB) boiler are being used together to achieve enhanced performance with lower overall costs. The need to understand the synergy between these two technologies is driven by deregulation of the power industry and the 1990 Clean Air Act Amendments. Deregulation of power production in the US has spurred the growth of Independent Power Producers (IPP) who are responding to Industry`s demand for lower cost fuels, and close attention to annual operating costs. Utilities have to provide {open_quotes}open{close_quotes} access to their transmission lines allowing various IPP`s to connect with the end user. Industrial users can now choose from one of several sources of electricity with prices per kilowatt hour that are much lower than what they are currently being charged. The race is on to reduce power production costs and fuel can be the key in many cases. IPP`s and industry are banding together in very logical ways that can benefit both. Industry`s byproducts with heating value can be sold {open_quotes}over the fence{close_quotes} to an IPP who provides the industry with low cost steam and or electricity in return. However, many alternative lower cost fuels also have a higher emissions potential for criteria pollutants such a SO{sub 2}, NO{sub X}, particulate, or other emissions such as VOC`s and mercury which are more recently receiving attention. Cost effective management of these environmental issues must be an integral part of the project planning process. Three such cases are examined that involve the use of CFB`s with the CDS{reg_sign} as a polishing scrubber for SO{sub 2}. The first two cases involve repowering of existing facilities with petroleum coke as the fuel. The last case involves a new facility powered with low sulfur coal.

  11. Effluent characterization from a conical pressurized fluid bed

    NASA Technical Reports Server (NTRS)

    Priem, R. J.; Rollbuhler, R. J.; Patch, R. W.

    1977-01-01

    To obtain useable corrosion and erosion results it was necessary to have data with several levels of particulate matter in the hot gases. One level of particulate loading was as low as possible so that ideally no erosion and only corrosion occurred. A conical fluidized bed was used to obtain some degree of filtration through the top of the bed which would not be highly fluidized. This would minimize the filtration required for the hot gases or conversely the amount of particulate matter in the hot gases after a given level of filtration by cyclones and/or filters. The data obtained during testing characterized the effluent from the bed at different test conditions. A range of bed heights, coal flows, air flows, limestone flows, and pressure are represented. These tests were made to determine the best operating conditions prior to using the bed to determine erosion and corrosion rates of typical turbine blade materials.

  12. Fluid-bed fluoride volatility process recovers uranium from spent uranium alloy fuels

    NASA Technical Reports Server (NTRS)

    Barghusen, J. J.; Chilenskas, A. A.; Gunderson, G. E.; Holmes, J. T.; Jonke, A. A.; Kincinas, J. E.; Levitz, N. M.; Potts, G. L.; Ramaswami, D.; Stethers, H.; Turner, K. S.

    1967-01-01

    Fluid-bed fluoride volatility process recovers uranium from uranium fuels containing either zirconium or aluminum. The uranium is recovered as uranium hexafluoride. The process requires few operations in simple, compact equipment, and eliminates aqueous radioactive wastes.

  13. Armoring, stability, and transport driven by fluid flow over a granular bed

    NASA Astrophysics Data System (ADS)

    Allen, Benjamin; Kudrolli, Arshad

    2015-03-01

    We discuss experiments investigating the evolution of a granular bed by a fluid flow as a function of shear rate at the fluid-bed interface. This is a model system to investigate a variety of physical examples including wind blowing over sand, sediment transport in rivers, tidal flows interacting with beaches, flows in slurry pipelines, and sand proppants in hydraulic fracturing. In order to examine the onset and entrainment of the granular bed under steady state conditions, we have constructed a novel conical rheometer system which allows a variable amount of shear to be applied to the granular bed. The grain-fluid system is index matched so that we can visualize the grains away from the sides as well as visualize the fluid flow above and below the interface by using fluorescent tracer particles. We demonstrate that the onset of erosion arises as particles rotate out of their stable position highlighting the importance of torque balance to onset. We find significant armoring of the bed, as the bed is sheared by the fluid flow. Above onset, at least three distinct regions of bed mobility can be found. We will discuss the measured integrated granular flux as a function of shear rate and compare them with empirical laws found in the geophysical literature. Supported by NSF Grant Number CBET 1335928.

  14. Rapid formulation screening with a Multipart Microscale Fluid bed Powder processor.

    PubMed

    Kivikero, Niina; Murtomaa, Matti; Antikainen, Osmo; Hatara, Juha; Juppo, Anne-Mari; Sandler, Niklas

    2011-08-01

    The aim of this study was to investigate early formulation screening in small scale with a miniaturized fluid bed device. Altogether eight different batches were granulated in a Multipart Microscale Fluid bed Powder processor (MMFP) with constant process conditions using electrostatic atomization. Atomization voltage and granulation liquid flow rate were kept constant. Acid acetylsalicylic was used as model active pharmaceutical ingredient (API), lactose monohydrate, microcrystalline cellulose and polyvinylpyrrolidone were used as excipients. Granule size distributions were measured with spatial filtering technique. Friability test was performed by spinning granules in the mixer with glass beads. Compressibility of the granules was evaluated by tableting and the breaking force of the tablets was measured. Multivariate analysis, namely partial least squares regression and multilinear regression were applied to the data. It was possible to generate granules of different compositions rapidly employing MMFP with electrostatic atomization fast and acquire reliable and logical results with only small amount of material. However, a major challenge was to find suitable analytical methods for such small batches.

  15. Partitioning of sodium, chlorine and sulfur during coal and char combustion in a fluid bed

    SciTech Connect

    Bhattacharya, S.P.; He, Y.

    1998-12-31

    Advanced power generation technologies (IGCC, Advanced PFBC) using high moisture low-rank coals require gasification of coal followed by combustion of char in a fluid bed. A study was undertaken to investigate the bed behaviour of char during combustion in a fluid bed. Three high moisture Australian low-rank coals, which are currently used in Victorian power stations, were chosen for this study. These were air dried, ground and sieved to 1--4 mm size. Char was prepared from these coals by devolatilising in a 76-mm diameter spouted bed at 700 C in presence of nitrogen. Char samples were combusted in the same spouted bed under hydrodynamic conditions similar to that in an atmospheric circulating fluid bed at temperatures of 800 C and 900 C. The three coal samples were also combusted under similar conditions to compare with the combustion behaviour of the char. No significant agglomeration problems were observed during combustion of these coals for periods of up to four hours. For one char, the bed defluidized 70 minutes after combustion at 900 C, while the two remaining chars didn`t present any significant agglomeration during the test period of four hours. Ultimate and inorganic analyses were carried out for the coal and char samples before the tests. The bed materials and cyclone ash after each combustion test were analyzed for inorganics and phases using chemical analysis, XRD and DTA techniques. A significant separation of the sodium and chlorine in coal was observed during pyrolysis of the coal to char. During combustion of char, most of the sodium (in char) was captured in the bed materials. This information was used to explain the bed behaviour observed during char combustion. This paper discusses the results and suggest strategies for mitigation of defluidization, that are currently under trial.

  16. Effects of exercise on fluid exchange and body composition in man during 14-day bed rest

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Bernauer, E. M.; Juhos, L. T.; Young, H. L.; Morse, J. T.; Staley, R. W.

    1977-01-01

    A description is presented of an investigation in which body composition, fluid intake, and fluid and electrolyte losses were measured in seven normal, healthy men during three 2-wk bed-rest periods, separated by two 3-wk recovery periods. During bed rest the subjects remained in the horizontal position continuously. During the dietary control periods, body mass decreased significantly with all three regimens, including no exercise, isometric exercise, and isotonic excercise. During bed rest, body mass was essentially unchanged with no exercise, but decreased significantly with isotonic and isometric exercise. With one exception, there were no statistically significant changes in body density, lean body mass, or body fat content by the end of each of the three bed-rest periods.

  17. Physiology of Fluid and Electrolyte Responses During Inactivity: Water Immersion and Bed Rest

    NASA Technical Reports Server (NTRS)

    Greenleaf, John E.

    1984-01-01

    This manuscript emphasizes the physiology of fluid-electrolyte-hormonal responses during the prolonged inactivity of bed rest and water immersion. An understanding of the total mechanism of adaptation (deconditioning) should provide more insight into the conditioning process. Findings that need to be confirmed during bed rest and immersion are: (1) the volume and tissues of origin of fluid shifted to the thorax and head; (2) interstitial fluid pressure changes in muscle and subcutaneous tissue, particularly during immersion; and (3) the composition of the incoming presumably interstitial fluid that contributes to the early hypervolemia. Better resolution of the time course and source of the diuretic fluid is needed. Important data will be forthcoming when hypotheses are tested involving the probable action of the emerging diuretic and natriuretic hormones, between themselves and among vasopressin and aldosterone, on diuresis and blood pressure control.

  18. Body fluid alterations during head-down bed rest in men at moderate altitude

    NASA Technical Reports Server (NTRS)

    Loeppky, J. A.; Roach, R. C.; Selland, M. A.; Scotto, P.; Luft, F. C.; Luft, U. C.

    1993-01-01

    To determine the effects of hypoxia on fluid balance responses to simulated zero-gravity, measurements were made in six subjects before and during -5 deg continuous head-down bed rest (HDBR) over 8 d at 10,678 ft. The same subjects were studied again at this altitude without HDBR as a control (CON) using a cross-over design. During this time, they maintained normal upright day-time activities, sleeping in the horizontal position at night. Fluid balance changes during HDBR in hypoxia were more pronounced than similar measurements previously reported from HDBR studies at sea level. Plasma volume loss was slightly greater and the diuresis and natriuresis were doubled in magnitude as compared to previous studies in normoxia and sustained for 4 d during hypoxia. These changes were associated with an immediate but transient rise in plasma atrial natriuretic peptide (ANP) to day 4 of 140 percent in HDBR and 41 percent in CON (p less than 0.005), followed by a decline towards baseline. Differences were less striking between HDBR and CON for plasma antidiuretic hormone and aldosterone, which were transiently reduced by HDBR. Plasma catecholamines showed a similar pattern to ANP in both HDBR and CON, suggesting that elevated ANP and catecholamines together accounted for the enhanced fluid shifts with HDBR during hypoxia.

  19. On-line monitoring of fluid bed granulation by photometric imaging.

    PubMed

    Soppela, Ira; Antikainen, Osmo; Sandler, Niklas; Yliruusi, Jouko

    2014-11-01

    This paper introduces and discusses a photometric surface imaging approach for on-line monitoring of fluid bed granulation. Five granule batches consisting of paracetamol and varying amounts of lactose and microcrystalline cellulose were manufactured with an instrumented fluid bed granulator. Photometric images and NIR spectra were continuously captured on-line and particle size information was extracted from them. Also key process parameters were recorded. The images provided direct real-time information on the growth, attrition and packing behaviour of the batches. Moreover, decreasing image brightness in the drying phase was found to indicate granule drying. The changes observed in the image data were also linked to the moisture and temperature profiles of the processes. Combined with complementary process analytical tools, photometric imaging opens up possibilities for improved real-time evaluation fluid bed granulation. Furthermore, images can give valuable insight into the behaviour of excipients or formulations during product development.

  20. Onset of erosion and sediment transport by a fluid flow over a granular bed

    NASA Astrophysics Data System (ADS)

    Kudrolli, Arshad

    Erosion and deposition of grains by a fluid flowing past the surface of a granular bed occurs in many natural and industrial processes. While considerable number of empirical studies has been conducted, very little is in fact known in detail on conditions which lead to erosion and deposition of sediments and their transport coefficients. We discuss a series of laboratory experiments to develop the physics of erosion starting with a single particle resting on a surface in a fluid flow. Fluorescent fluid-particle index matching techniques allow us to visualize not only the particles at the surface of a granular bed but also the flow within the bed and the individual particles within the bed. We will discuss the conditions governing the onset of particle motion under simple shear and their transport as a function of bed and fluid flow properties. Supported by the U.S. DOE Office of Science and Office of BES program under DE-FG02-13ER16401, and NSF Grant No. CBET-1335928.

  1. Users investing own funds in large fluid bed systems

    SciTech Connect

    Poplett, J.

    1984-11-05

    The successful performance of atmospheric fluidized bed (AFB) boilers funded by government grants has encouraged industrial users to invest their own capital for large AFB boilers as a means of safely switching to coal. The successful demonstrations, the corrections of corrosion problems, the ability of AFB boilers to comply with emission standards without needing costly pollution control equipment, the ability to burn low-grade coal or coal by-products, and quick paybacks triggered the interest despite stable oil and gas prices. However, interest in systems below 100,000 pounds per hour is dropping because of long payback periods. A directory lists 15 manufacturers of AFB boilers.

  2. The SEI facility for fluid-bed wood gasification

    SciTech Connect

    Bullpitt, W.S.; Rittenhouse, O.C. ); Masterson, L.D. )

    1989-09-01

    In mid 1985, construction was begun on the world's largest fluidized bed, wood gasification plant at the clay processing plant in Quincy, Fla. In March 1986, the plant was purchased by Southern Electric International (SEI). This paper describes how SEI coordinated the redesign of many of the plant systems and supervised the completion of construction and startup. In late 1986, the gasifier plant was sold. SEI remains involved as the operations and maintenance contractor on-site and is now responsible for design changes and equipment maintenance.

  3. Turbulent flow over a channel with fluid-saturated porous bed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The characteristics of fully developed turbulent flow in a hybrid domain channel, which consists of a clear fluid region and a porous bed, are examined numerically using a model based on the macroscopic Reynolds-averaged Navier–Stokes equations. By adopting the classical continuity interface conditi...

  4. The Hydrodynamic Stability of a Fluid-Particle Flow: Instabilities in Gas-Fluidized Beds

    ERIC Educational Resources Information Center

    Liu, Xue; Howley, Maureen A.; Johri, Jayati; Glasser, Benjamin J.

    2008-01-01

    A simplified model of an industrially relevant fluid-particle flow system is analyzed using linear stability theory. Instabilities of the uniform state of a fluidized bed are investigated in response to small flow perturbations. Students are expected to perform each step of the computational analysis, and physical insight into key mechanistic…

  5. Analysis and control of the METC fluid bed gasifier. Quarterly report, April 1995--June 1995

    SciTech Connect

    1995-06-01

    This document summarizes work performed for the period 4/1/95 to 7/31/95 on contract no. DE-FG21-94MC31384 (Work accomplished during the period 10/1/94 to 3/31/94 was summarized in the previous technical progress report included in the appendix of this report). In this work, three components will form the basis for design of a control scheme for the Fluidized Bed Gasifier (FBG) at METC: (1) a control systems analysis based on simple linear models derived from process data, (2) review of the literature on fluid bed gasifier operation and control, and (3) understanding of present FBG operation and real world considerations. Tasks accomplished during the present reporting period include: (1) Completion of a literature survey on Fluid Bed Gasifier control, (2) Observation of the FBG during the week of July 17 to July 21, and (3) Suggested improvements to the control of FBG backpressure and MGCR pressure.

  6. Centaur Test Bed (CTB) for Cryogenic Fluid Management

    NASA Technical Reports Server (NTRS)

    Sakla, Steven; Kutter, Bernard; Wall, John

    2006-01-01

    Future missions such as NASA s space exploration vision and DOD satellite servicing will require significant increases in the understanding and knowledge of space based cryogenic fluid management (CFM), including the transfer and storage of cryogenic fluids. Existing CFM capabilities are based on flight of upper stage cryogenic vehicles, scientific dewars, a few dedicated flight demonstrations and ground testing. This current capability is inadequate to support development of the CEV cryogenic propulsion system, other aspects of robust space exploration or the refueling of satellite cryo propulsion systems with reasonable risk. In addition, these technologies can provide significant performance increases for missions beyond low-earth orbit to enable manned missions to the Moon and beyond. The Centaur upper-stage vehicle can provide a low cost test platform for performing numerous flight demonstrations of the full breadth of required CFM technologies to support CEV development. These flight demonstrations can be performed as secondary mission objectives using excess LH2 and/or LO2 from the main vehicle propellant tanks following primary spacecraft separation at minimal cost and risk.

  7. Fluid-Bed Testing of Greatpoint Energy's Direct Oxygen Injection Catalytic Gasification Process for Synthetic Natural Gas and Hydrogen Coproduction Year 6 - Activity 1.14 - Development of a National Center for Hydrogen Technology

    SciTech Connect

    Swanson, Michael; Henderson, Ann

    2012-04-01

    The GreatPoint Energy (GPE) concept for producing synthetic natural gas and hydrogen from coal involves the catalytic gasification of coal and carbon. GPE’s technology “refines” coal by employing a novel catalyst to “crack” the carbon bonds and transform the coal into cleanburning methane (natural gas) and hydrogen. The GPE mild “catalytic” gasifier design and operating conditions result in reactor components that are less expensive and produce pipeline-grade methane and relatively high purity hydrogen. The system operates extremely efficiently on very low cost carbon sources such as lignites, subbituminous coals, tar sands, petcoke, and petroleum residual oil. In addition, GPE’s catalytic coal gasification process eliminates troublesome ash removal and slagging problems, reduces maintenance requirements, and increases thermal efficiency, significantly reducing the size of the air separation plant (a system that alone accounts for 20% of the capital cost of most gasification systems) in the catalytic gasification process. Energy & Environmental Research Center (EERC) pilot-scale gasification facilities were used to demonstrate how coal and catalyst are fed into a fluid-bed reactor with pressurized steam and a small amount of oxygen to “fluidize” the mixture and ensure constant contact between the catalyst and the carbon particles. In this environment, the catalyst facilitates multiple chemical reactions between the carbon and the steam on the surface of the coal. These reactions generate a mixture of predominantly methane, hydrogen, and carbon dioxide. Product gases from the process are sent to a gas-cleaning system where CO{sub 2} and other contaminants are removed. In a full-scale system, catalyst would be recovered from the bottom of the gasifier and recycled back into the fluid-bed reactor. The by-products (such as sulfur, nitrogen, and CO{sub 2}) would be captured and could be sold to the chemicals and petroleum industries, resulting in

  8. Axial dispersion in packed bed reactors involving viscoinelastic and viscoelastic non-Newtonian fluids.

    PubMed

    Gupta, Renu; Bansal, Ajay

    2013-08-01

    Axial dispersion is an important parameter in the performance of packed bed reactors. A lot of fluids exhibit non-Newtonian behaviour but the effect of rheological parameters on axial dispersion is not available in literature. The effect of rheology on axial dispersion has been analysed for viscoinelastic and viscoelastic non-Newtonian fluids. Aqueous solutions of carboxymethyl cellulose and polyacrylamide have been chosen to represent viscoinelastic and viscoelastic liquid-phases. Axial dispersion has been measured in terms of BoL number. The single parameter axial dispersion model has been applied to analyse RTD response curve. The BoL numbers were observed to increase with increase in liquid flow rate and consistency index 'K' for viscoinelastic as well as viscoelastic fluids. Bodenstein correlation for Newtonian fluids proposed has been modified to account for the effect of fluid rheology. Further, Weissenberg number is introduced to quantify the effect of viscoelasticity.

  9. Fluid and salt supplementation effect on body hydration and electrolyte homeostasis during bed rest and ambulation

    NASA Astrophysics Data System (ADS)

    Zorbas, Yan G.; Kakurin, Vassily J.; Kuznetsov, Nikolai A.; Yarullin, Vladimir L.

    2002-06-01

    Bed rest (BR) induces significant urinary and blood electrolyte changes, but little is known about the effect of fluid and salt supplements (FSS) on catabolism, hydration and electrolytes. The aim was to measure the effect of FSS on catabolism, body hydration and electrolytes during BR. Studies were done during 7 days of a pre-bed rest period and during 30 days of a rigorous bed rest period. Thirty male athletes aged, 24.6±7.6 years were chosen as subjects. They were divided into three groups: unsupplemented ambulatory control subjects (UACS), unsupplemented bed rested subjects (UBRS) and supplemented bed rested subjects (SBRS). The UBRS and SBRS groups were kept under a rigorous bed rest regime for 30 days. The SBRS daily took 30 ml water per kg body weight and 0.1 sodium chloride per kg body weight. Plasma sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg) levels, urinary Na, K, Ca and Mg excretion, plasma osmolality, plasma protein level, whole blood hemoglobin (Hb) and hematocrit (Hct) level increased significantly ( p≤0.05), while plasma volume (PV), body weight, body fat, peak oxygen uptake, food and fluid intake decreased significantly ( p≤0.05) in the UBRS group when compared with the SBRS and UACS groups. In contrast, plasma and urinary electrolytes, osmolality, protein level, whole blood Hct and Hb level decreased significantly ( p≤0.05), while PV, fluid intake, body weight and peak oxygen uptake increased significantly ( p≤0.05) in the SBRS group when compared with the UBRS group. The measured parameters did not change significantly in the UACS group when compared with their baseline control values. The data indicate that FSS stabilizes electrolytes and body hydration during BR, while BR alone induces significant changes in electrolytes and body hydration. We conclude that FSS may be used to prevent catabolism and normalize body hydration status and electrolyte values during BR.

  10. Analysis and control of the METC fluid bed gasifier. Quarterly progress report, January--March 1995

    SciTech Connect

    1995-03-01

    This document summarizes work performed for the period 10/1/94 to 3/31/95. In this work, three components will form the basis for design of a control scheme for the Fluidized Bed Gasifier (FBG) at METC: (1) a control systems analysis based on simple linear models derived from process data, (2) review of the literature on fluid bed gasifier operation and control, and (3) understanding of present FBG operation and real world considerations. Below we summarize work accomplished to data in each of these areas.

  11. Composition of fluid inclusions in Permian salt beds, Palo Duro Basin, Texas, U.S.A.

    USGS Publications Warehouse

    Roedder, E.; d'Angelo, W. M.; Dorrzapf, A.F.; Aruscavage, P. J.

    1987-01-01

    Several methods have been developed and used to extract and chemically analyze the two major types of fluid inclusions in bedded salt from the Palo Duro Basin, Texas. Data on the ratio K: Ca: Mg were obtained on a few of the clouds of tiny inclusions in "chevron" salt, representing the brines from which the salt originally crystallized. Much more complete quantitative data (Na, K, Ca, Mg, Sr, Cl, SO4 and Br) were obtained on ??? 120 individual "large" (mostly ???500 ??m on an edge, i.e., ??? ??? 1.6 ?? 10-4 g) inclusions in recrystallized salt. These latter fluids have a wide range of compositions, even in a given piece of core, indicating that fluids of grossly different composition were present in these salt beds during the several (?) stages of recrystallization. The analytical results indicating very large inter-and intra-sample chemical variation verify the conclusion reached earlier, from petrography and microthermometry, that the inclusion fluids in salt and their solutes are generally polygenetic. The diversity in composition stems from the combination of a variety of sources for the fluids (Permian sea, meteoric, and groundwater, as well as later migrating ground-, formation, or meteoric waters of unknown age), and a variety of subsequent geochemical processes of dissolution, precipitation and rock-water interaction. The compositional data are frequently ambiguous but do provide constraints and may eventually yield a coherent history of the events that produced these beds. Such an understanding of the past history of the evaporite sequence of the Palo Duro Basin should help in predicting the future role of the fluids in the salt if a nuclear waste repository is sited there. ?? 1987.

  12. Recent circulating fluid bed (CFB) boiler projects in the U. S. and Europe

    SciTech Connect

    Lund, T.; Anders, R.; Capuano, L.; Fox, S.; Plass, L.

    1983-11-01

    Lurgi Chemie and Huettentechnik has developed the circulating fluid bed process for solid fuel combustion and steam generation. This process has been commercially proven at Luenen, West Germany. Lurgi Chemie is also currently building two additional CFB boilers in Germany which will produce 595,000 pph and 331,000 pph of steam, respectively. In the U.S., Lurgi Corporation and Combustion Engineering have signed an agreement to jointly design, manufacture and sell CFB plants in the U.S. and Canada. The circular fluid bed process itself is a system which can burn a wide variety of inexpensive, low grade solid fules efficiently, economically and in an environmentally acceptable manner. The details of these CFB boilers are examined in this article.

  13. Critical evaluation and comparison of fluid distribution systems for industrial scale expanded bed adsorption chromatography columns.

    PubMed

    Arpanaei, A; Heebøll-Nielsen, A; Hubbuch, J J; Thomas, O R T; Hobley, T J

    2008-07-11

    The hydrodynamic properties of an expanded bed contactor with 30 cm or 150 cm internal diameter, which employs a rotating or oscillating fluid distributor, were compared to prototype columns of 60 cm or 150 cm diameter employing local stirring (fixed wall nozzles plus central bottom mounted stirrer) for fluid distribution. Fluid introduction through a rotating fluid distributor was found to give superior hydrodynamic characteristics in the 30 cm and 150 cm diameter column compared to using the local stirrer in both the 60 cm and 150 cm diameter columns. The shortcomings of the local stirring distributor at large scale were apparent: dead zones were present which could not be removed by increasing rotation rates or flow rates, and such changes led to a deterioration in hydrodynamic properties. In contrast, during fluid introduction through a rotating distributor no dead zones were observed, and residence time distribution tests showed that plate numbers remained constant or increased slightly as flow rate was raised from 200 cm h(-1) to 470 cm h(-1). Under the conditions studied, oscillation of the rotating fluid distributor led to increased mixing and poorer performance than rotary movement. The results imply that further improvement in distributor design is needed and careful attention should be given to the trade off between turbulence and adequate fluid distribution.

  14. Onset of motion at the surface of a porous granular bed by a shearing fluid flow

    NASA Astrophysics Data System (ADS)

    Hong, Anyu; Tao, Mingjiang; Kudrolli, Arshad

    2014-03-01

    We will discuss an experimental investigation of the onset of particle motion by a fluid flow over an unconsolidated granular bed. This situation arises in a number of natural and industrial processes including wind blowing over sand, sediment transport in rivers, tidal flows interacting with beaches and flows in slurry pipelines and mixing tanks. The Shields criteria given by the ratio of the viscous shear and normal stresses is used to understand the onset of motion. However, reviews reveals considerable scatter while noting broad trends with Reynolds Number. We discuss an idealized model system where fluid flows with a prescribed flow rate through a horizontal rectangular pipe initially fully filled with granular beads. The granular bed height decreases and reaches a constant height when the shear stress at the boundary decreases below a critical value. We compare and contrast the values obtained assuming no-slip boundary conditions with those observed with PIV using florescent tracer particles to measure the actual fluid flow profile near the porous interface. We will also report the observed variation of the Shields criteria with particle Reynolds Number by varying particle size and fluid flow rates.

  15. Study of ebullated bed fluid dynamics. Final progress report, September 1980-July 1983

    SciTech Connect

    Schaefer, R.J.; Rundell, D.N.; Shou, J.K.

    1983-07-01

    The fluid dynamics occurring in HRI's H-coal process development unit coal liquefaction reactor during Run PDU-10 were measured and compared with Amoco Oil cold-flow fluidization results. It was found that catalyst bed expansions and gas holdups are higher in the PDU than those observed in the cold-flow tests for slurries having the same nominal viscosity. Comparison of PDU results with cold-flow results shows that the bulk of the operating reactor gas flow lies in the ideal bubbly regime. It also appears that the gas bubbles in these PDU tests are rising quite slowly. Only two of the operating points in our test program on the PDU were found to lie in the churn turbulent regime. Existence of churn turbulent behavior during these two experiments is consistent with trends observed in earlier cold-flow experiments. Two- and three-phase fluidization experiments were carried out in Amoco's cold-flow fluid dynamics unit. The data base now includes fluidization results for coal char/kerosene slurry concentrations of 4.0, 9.8, and 20.7 vol% in addition to the 15.5 and 17.8 vol% data from our earlier work. Both HDS-2A and Amocat-1A catalysts were used in the tests. Bed expansion is primarily a function of slurry velocity, with gas velocity having only a weak effect. Bed contractions have been observed in some cases at sufficiently high gas velocity. Gas and liquid holdups were found to be uniform across the cross-section of the Amoco cold-flow fluid dynamics pilot plant. A viscometer was adapted for measurement of the viscosity of coal slurries at high temperature and pressure. Based on experiments carried out in the Amoco cold-flow unit, a significant degree of backmixing was found to occur in the H-Coal system. 70 references, 93 figures, 32 tables.

  16. CFD study on local fluid-to-wall heat transfer in packed beds and field synergy analysis

    NASA Astrophysics Data System (ADS)

    Peng, Wenping; Xu, Min; Huai, Xiulan; Liu, Zhigang

    2016-04-01

    To reach the target of smaller pressure drop and better heat transfer performance, packed beds with small tube-to-particle diameter ratio ( D/d p<10) have now been considered in many areas. Fluid-to-wall heat transfer coefficient is an important factor determining the performance of this type of beds. In this work, local fluid- to-wall heat transfer characteristic in packed beds was studied by Computational Fluid Dynamics (CFD) at different Reynolds number for D/d p=1.5, 3.0 and 5.6. The results show that the fluid-to-wall heat transfer coefficient is oscillating along the bed with small tube-to-particle diameter ratio. Moreover, this phenomenon was explained by field synergy principle in detail. Two arrangement structures of particles in packed beds were recommended based on the synergy characteristic between flow and temperature fields. This study provides a new local understanding of fluid-to-wall heat transfer in packed beds with small tube-to-particle diameter ratio.

  17. Coupling scales for modelling heavy metal vaporization from municipal solid waste incineration in a fluid bed by CFD.

    PubMed

    Soria, José; Gauthier, Daniel; Flamant, Gilles; Rodriguez, Rosa; Mazza, Germán

    2015-09-01

    Municipal Solid Waste Incineration (MSWI) in fluidized bed is a very interesting technology mainly due to high combustion efficiency, great flexibility for treating several types of waste fuels and reduction in pollutants emitted with the flue gas. However, there is a great concern with respect to the fate of heavy metals (HM) contained in MSW and their environmental impact. In this study, a coupled two-scale CFD model was developed for MSWI in a bubbling fluidized bed. It presents an original scheme that combines a single particle model and a global fluidized bed model in order to represent the HM vaporization during MSW combustion. Two of the most representative HM (Cd and Pb) with bed temperatures ranging between 923 and 1073K have been considered. This new approach uses ANSYS FLUENT 14.0 as the modelling platform for the simulations along with a complete set of self-developed user-defined functions (UDFs). The simulation results are compared to the experimental data obtained previously by the research group in a lab-scale fluid bed incinerator. The comparison indicates that the proposed CFD model predicts well the evolution of the HM release for the bed temperatures analyzed. It shows that both bed temperature and bed dynamics have influence on the HM vaporization rate. It can be concluded that CFD is a rigorous tool that provides valuable information about HM vaporization and that the original two-scale simulation scheme adopted allows to better represent the actual particle behavior in a fluid bed incinerator.

  18. In Situ Decommissioning Sensor Network, Meso-Scale Test Bed - Phase 3 Fluid Injection Test Summary Report

    SciTech Connect

    Serrato, M. G.

    2013-09-27

    located at the Florida International University Applied Research Center, Miami, FL (FIU-ARC). A follow-on fluid injection test was developed to detect fluid and ion migration in a cementitious material/grouted test cube using a limited number of existing embedded sensor systems. This In Situ Decommissioning Sensor Network, Meso-Scale Test Bed (ISDSN-MSTB) - Phase 3 Fluid Injection Test Summary Report summarizes the test implementation, acquired and processed data, and results from the activated embedded sensor systems used during the fluid injection test. The ISDSN-MSTB Phase 3 Fluid Injection Test was conducted from August 27 through September 6, 2013 at the FIU-ARC ISDSN-MSTB test cube. The fluid injection test activated a portion of the existing embedded sensor systems in the ISDSN-MSTB test cube: Electrical Resistivity Tomography-Thermocouple Sensor Arrays, Advance Tensiometer Sensors, and Fiber Loop Ringdown Optical Sensors. These embedded sensor systems were activated 15 months after initial placement. All sensor systems were remotely operated and data acquisition was completed through the established Sensor Remote Access System (SRAS) hosted on the DOE D&D Knowledge Management Information Tool (D&D DKM-IT) server. The ISDN Phase 3 Fluid Injection Test successfully demonstrated the feasibility of embedding sensor systems to assess moisture-fluid flow and resulting transport potential for contaminate mobility through a cementitious material/grout monolith. The ISDSN embedded sensor systems activated for the fluid injection test highlighted the robustness of the sensor systems and the importance of configuring systems in-depth (i.e., complementary sensors and measurements) to alleviate data acquisition gaps.

  19. Coupling scales for modelling heavy metal vaporization from municipal solid waste incineration in a fluid bed by CFD

    SciTech Connect

    Soria, José; Gauthier, Daniel; Flamant, Gilles; Rodriguez, Rosa; Mazza, Germán

    2015-09-15

    Highlights: • A CFD two-scale model is formulated to simulate heavy metal vaporization from waste incineration in fluidized beds. • MSW particle is modelled with the macroscopic particle model. • Influence of bed dynamics on HM vaporization is included. • CFD predicted results agree well with experimental data reported in literature. • This approach may be helpful for fluidized bed reactor modelling purposes. - Abstract: Municipal Solid Waste Incineration (MSWI) in fluidized bed is a very interesting technology mainly due to high combustion efficiency, great flexibility for treating several types of waste fuels and reduction in pollutants emitted with the flue gas. However, there is a great concern with respect to the fate of heavy metals (HM) contained in MSW and their environmental impact. In this study, a coupled two-scale CFD model was developed for MSWI in a bubbling fluidized bed. It presents an original scheme that combines a single particle model and a global fluidized bed model in order to represent the HM vaporization during MSW combustion. Two of the most representative HM (Cd and Pb) with bed temperatures ranging between 923 and 1073 K have been considered. This new approach uses ANSYS FLUENT 14.0 as the modelling platform for the simulations along with a complete set of self-developed user-defined functions (UDFs). The simulation results are compared to the experimental data obtained previously by the research group in a lab-scale fluid bed incinerator. The comparison indicates that the proposed CFD model predicts well the evolution of the HM release for the bed temperatures analyzed. It shows that both bed temperature and bed dynamics have influence on the HM vaporization rate. It can be concluded that CFD is a rigorous tool that provides valuable information about HM vaporization and that the original two-scale simulation scheme adopted allows to better represent the actual particle behavior in a fluid bed incinerator.

  20. Catalytically Active Regenerative Sorbent beds (CARS) for airborne contaminants.

    PubMed

    Akse, J R; Thompson, J O

    1995-01-01

    The Pd on Al2O3 catalyst used in the projected Space Station's Trace Contaminant Control System (TCCS) catalytic oxidizer can be poisoned by volatile halogen-, sulfur-, and nitrogen-containing organic species. Catalytically Active Regenerable Sorbents (CARS) eliminate these problematic contaminants and the large carbon bed used for their elimination in a three-step process. Contaminants are conventionally adsorbed by the CARS bed. After saturation, the bed is connected to an off-line recirculation loop, filled with hydrogen, and then heated. At temperature, contaminants are hydrogenated on catalytic sites within the bed, forming simple alkanes and acid gases that are efficiently converted to innocuous salts in an in-line alkaline bed. The CARS bed is regenerated by this cycle and alkane gases are released to be safely oxidized in the catalytic oxidizer. A challenge mixture containing Freon-113, thiophene, trichloroethylene, Halon-1301, and dichloromethane at 1670, 75, 81, 68, and 83 mg/m3 was successfully treated using this technology, demonstrating the CARS feasibility.

  1. Regulation of muscle sympathetic nerve activity after bed rest deconditioning

    NASA Technical Reports Server (NTRS)

    Pawelczyk, J. A.; Zuckerman, J. H.; Blomqvist, C. G.; Levine, B. D.

    2001-01-01

    Cardiovascular deconditioning reduces orthostatic tolerance. To determine whether changes in autonomic function might produce this effect, we developed stimulus-response curves relating limb vascular resistance, muscle sympathetic nerve activity (MSNA), and pulmonary capillary wedge pressure (PCWP) with seven subjects before and after 18 days of -6 degrees head-down bed rest. Both lower body negative pressure (LBNP; -15 and -30 mmHg) and rapid saline infusion (15 and 30 ml/kg body wt) were used to produce a wide variation in PCWP. Orthostatic tolerance was assessed with graded LBNP to presyncope. Bed rest reduced LBNP tolerance from 23.9 +/- 2.1 to 21.2 +/- 1.5 min, respectively (means +/- SE, P = 0.02). The MSNA-PCWP relationship was unchanged after bed rest, though at any stage of the LBNP protocol PCWP was lower, and MSNA was greater. Thus bed rest deconditioning produced hypovolemia, causing a shift in operating point on the stimulus-response curve. The relationship between limb vascular resistance and MSNA was not significantly altered after bed rest. We conclude that bed rest deconditioning does not alter reflex control of MSNA, but may produce orthostatic intolerance through a combination of hypovolemia and cardiac atrophy.

  2. Fluid bed drying of guarana (Paullinia cupana HBK) extract: effect of process factors on caffeine content.

    PubMed

    Pagliarussi, Renata S; Bastos, Jairo K; Freitas, Luis A P

    2006-06-16

    The aim of this study was to study the convective drying of the hydroalcoholic extracts obtained from powdered guarana seeds in a spouted bed dryer. The influence of process variables, such as the convective airflow rate, extract feed rate, and air inlet temperature, on the quality of the dry extract was determined using the caffeine and moisture content for the process evaluation. The caffeine content in the alcoholic and dried extracts was determined by capillary gas chromatography. The experiments were performed following a 3(3) factorial design and the data analyzed by response surface. The analysis of dry extract showed that the air and extract feed rates did not significantly affect (25% level) the caffeine content, but that drying temperature is a major factor to consider when the extract is submitted to fluid bed drying. Caffeine losses were significant (1% level) for drying temperatures above 120 degrees C, while moisture content was lower than 3% for temperatures above 120 degrees C. The data showed that there is an optimum temperature for the drying of guarana extracts in spouted beds, and under the conditions used in this study it was 120 degrees C.

  3. Test plan for valveless ash removal from pressurized fluid bed combustion systems

    SciTech Connect

    Hauserman, W.B.

    1989-07-01

    This is a test plan to demonstrate a method of ash removal from pressurized fluid bed combustion (PFBC) systems through small beds of crushed rock rather than conventional pressure let-down valves and lock hoppers. The economic advantage of such a method is that process-inherent erosive damage will be inflicted upon the cheaply replaceable crushed rock, rather than upon expensive, fabricated valve trim components. The concept to be tested is an extension of the gravel bucket'' principle in which an erosive, high pressure slurry stream passes through a bed of crushed rock with an adjustable flow path and cross-section. The original gravel bucket concept was inspired by the costly valve erosion problems projected for coal liquefaction plants. This project extends the same approach to systems where solids are to be removed from PFBC systems, with more limited possibilities of application to some coal gasification processes. If proven successful, a hot-gas gravel bucket could offer an economic alternative to a lock hopper plus a pair of expensive block valves. 6 refs., 10 figs., 1 tab.

  4. Granule size control and targeting in pulsed spray fluid bed granulation.

    PubMed

    Ehlers, Henrik; Liu, Anchang; Räikkönen, Heikki; Hatara, Juha; Antikainen, Osmo; Airaksinen, Sari; Heinämäki, Jyrki; Lou, Honxiang; Yliruusi, Jouko

    2009-07-30

    The primary aim of the study was to investigate the effects of pulsed liquid feed on granule size. The secondary aim was to increase knowledge of this technique in granule size targeting. Pulsed liquid feed refers to the pump changing between on- and off-positions in sequences, called duty cycles. One duty cycle consists of one on- and off-period. The study was performed with a laboratory-scale top-spray fluid bed granulator with duty cycle length and atomization pressure as studied variables. The liquid feed rate, amount and inlet air temperature were constant. The granules were small, indicating that the powder has only undergone ordered mixing, nucleation and early growth. The effect of atomizing pressure on granule size depends on inlet air relative humidity, with premature binder evaporation as a reason. The duty cycle length was of critical importance to the end product attributes, by defining the extent of intermittent drying and rewetting. By varying only the duty cycle length, it was possible to control granule nucleation and growth, with a wider granule size target range in increased relative humidity. The present study confirms that pulsed liquid feed in fluid bed granulation is a useful tool in end product particle size targeting.

  5. Effects of Daily Centrifugation on Segmental Fluid Distribution in Bed-rested Subjects

    NASA Technical Reports Server (NTRS)

    Diedrich, Andre; Moore, S. T.; Stenger, M.; Arya, T. M.; Newby, N.; Tucker, J. M.; Milstead, L.; Acock, K.; Knapp, C.; Jevans, J.; Paloski, W.

    2007-01-01

    The effect of daily centrifugation on segmental fluid distribution have been studied during 21 days of 6 degree head down bedrest. One group (N=7) underwent no countermeasure while the other (N=8) received a daily, one hour, dose (2.5 gz at the foot, decreasing to 1.0 gz at the heart) of artificial gravity (AG) training on the Johnson Space Center short radius centrifuge. Fluid shifts of thoracic(VTO), abdominal (VAB), thigh (VTH), and calf (VCA) regions were measured by the tetrapolar segmental body impedance technique. Untrained subjects reduced their total volume from 18.9 plus or minus 0.5L to 17.9 plus or minus 0.9L (MN plus or minus SE, P less than 0.05) while trained subjects maintained their total volume. In untrained, control, subjects after bed rest, there was a trend toward reduced volume in all segments, with significant reductions in thigh and calf (fig, P less than 0.05). Trained subjects maintained volume in all segments. Our data indicate that artificial gravity treatment counteracts bed rest-induced hypovolemia.

  6. Manufacturing Solid Dosage Forms from Bulk Liquids Using the Fluid-bed Drying Technology.

    PubMed

    Qi, Jianping; Lu, Y I; Wu, Wei

    2015-01-01

    Solid dosage forms are better than liquid dosage forms in many ways, such as improved physical and chemical stability, ease of storage and transportation, improved handling properties, and patient compliance. Therefore, it is required to transform dosage forms of liquid origins into solid dosage forms. The functional approaches are to absorb the liquids by solid excipients or through drying. The conventional drying technologies for this purpose include drying by heating, vacuum-, freeze- and spray-drying, etc. Among these drying technologies, fluidbed drying emerges as a new technology that possesses unique advantages. Fluid-bed drying or coating is highly efficient in solvent removal, can be performed at relatively low temperatures, and is a one-step process to manufacture formulations in pellet forms. In this article, the status of the art of manufacturing solid dosage forms from bulk liquids by fluid-bed drying technology was reviewed emphasizing on its application in solid dispersion, inclusion complexes, self-microemulsifying systems, and various nanoscale drug delivery systems.

  7. Fluid flow through a high cell density fluidized-bed during centrifugal bioreactor culture.

    PubMed

    Detzel, Christopher J; Van Wie, Bernard J; Ivory, Cornelius F

    2010-01-01

    An increasing demand for products such as tissues, proteins, and antibodies from mammalian cell suspension cultures is driving interest in increasing production through high-cell density bioreactors. The centrifugal bioreactor (CCBR) retains cells by balancing settling forces with surface drag forces due to medium throughput and is capable of maintaining cell densities above 10(8) cells/mL. This article builds on a previous study where the fluid mechanics of an empty CCBR were investigated showing fluid flow is nonuniform and dominated by Coriolis forces, raising concerns about nutrient and cell distribution. In this article, we demonstrate that the previously reported Coriolis forces are still present in the CCBR, but masked by the presence of cells. Experimental dye injection observations during culture of 15 microm hybridoma cells show a continual uniform darkening of the cell bed, indicating the region of the reactor containing cells is well mixed. Simulation results also indicate the cell bed is well mixed during culture of mammalian cells ranging in size from 10 to 20 microm. However, simulations also allow for a slight concentration gradient to be identified and attributed to Coriolis forces. Experimental results show cell density increases from 0.16 to 0.26 when centrifugal force is doubled by increasing RPM from 650 to 920 at a constant inlet velocity of 6.5 cm/s; an effect also observed in the simulation. Results presented in this article indicate cells maintained in the CCBR behave as a high-density fluidized bed of cells providing a homogeneous environment to ensure optimal growth conditions.

  8. Fluid Flow through a High Cell Density Fluidized-Bed during Centrifugal Bioreactor Culture

    PubMed Central

    Detzel, Christopher J.; Van Wie, Bernard J.; Ivory, Cornelius F.

    2010-01-01

    An increasing demand for products such as tissues, proteins, and antibodies from mammalian cell suspension cultures is driving interest in increasing production through high-cell density bioreactors. The centrifugal bioreactor (CCBR) retains cells by balancing settling forces with surface drag forces due to medium throughput and is capable of maintaining cell densities above 108 cells/mL. This article builds on a previous study where the fluid mechanics of an empty CCBR were investigated showing fluid flow is nonuniform and dominated by Coriolis forces, raising concerns about nutrient and cell distribution. In this article, we demonstrate that the previously reported Coriolis forces are still present in the CCBR, but masked by the presence of cells. Experimental dye injection observations during culture of 15 μm hybridoma cells show a continual uniform darkening of the cell bed, indicating the region of the reactor containing cells is well mixed. Simulation results also indicate the cell bed is well mixed during culture of mammalian cells ranging in size from 10 to 20 μm. However, simulations also allow for a slight concentration gradient to be identified and attributed to Coriolis forces. Experimental results show cell density increases from 0.16 to 0.26 when centrifugal force is doubled by increasing RPM from 650 to 920 at a constant inlet velocity of 6.5 cm/s; an effect also observed in the simulation. Results presented in this article indicate cells maintained in the CCBR behave as a high-density fluidized bed of cells providing a homogeneous environment to ensure optimal growth conditions. PMID:20205172

  9. Immersed Boundary Simulations of Active Fluid Droplets

    PubMed Central

    Hawkins, Rhoda J.

    2016-01-01

    We present numerical simulations of active fluid droplets immersed in an external fluid in 2-dimensions using an Immersed Boundary method to simulate the fluid droplet interface as a Lagrangian mesh. We present results from two example systems, firstly an active isotropic fluid boundary consisting of particles that can bind and unbind from the interface and generate surface tension gradients through active contractility. Secondly, a droplet filled with an active polar fluid with homeotropic anchoring at the droplet interface. These two systems demonstrate spontaneous symmetry breaking and steady state dynamics resembling cell motility and division and show complex feedback mechanisms with minimal degrees of freedom. The simulations outlined here will be useful for quantifying the wide range of dynamics observable in these active systems and modelling the effects of confinement in a consistent and adaptable way. PMID:27606609

  10. Fluid transport by active elastic membranes

    NASA Astrophysics Data System (ADS)

    Evans, Arthur A.; Lauga, Eric

    2011-09-01

    A flexible membrane deforming its shape in time can self-propel in a viscous fluid. Alternatively, if the membrane is anchored, its deformation will lead to fluid transport. Past work in this area focused on situations where the deformation kinematics of the membrane were prescribed. Here we consider models where the deformation of the membrane is not prescribed, but instead the membrane is internally forced. Both the time-varying membrane shape and the resulting fluid motion result then from a balance between prescribed internal active stresses, internal passive resistance, and external viscous stresses. We introduce two specific models for such active internal forcing: one where a distribution of active bending moments is prescribed, and one where active inclusions exert normal stresses on the membrane by pumping fluid through it. In each case, we asymptotically calculate the membrane shape and the fluid transport velocities for small forcing amplitudes, and recover our results using scaling analysis.

  11. Circulating fluidized bed hydrodynamics experiments for the multiphase fluid dynamics research consortium (MFDRC).

    SciTech Connect

    Oelfke, John Barry; Torczynski, John Robert; O'Hern, Timothy John; Tortora, Paul Richard; Bhusarapu, Satish; Trujillo, Steven Mathew

    2006-08-01

    An experimental program was conducted to study the multiphase gas-solid flow in a pilot-scale circulating fluidized bed (CFB). This report describes the CFB experimental facility assembled for this program, the diagnostics developed and/or applied to make measurements in the riser section of the CFB, and the data acquired for several different flow conditions. Primary data acquired included pressures around the flow loop and solids loadings at selected locations in the riser. Tomographic techniques using gamma radiation and electrical capacitance were used to determine radial profiles of solids volume fraction in the riser, and axial profiles of the integrated solids volume fraction were produced. Computer Aided Radioactive Particle Tracking was used to measure solids velocities, fluxes, and residence time distributions. In addition, a series of computational fluid dynamics simulations was performed using the commercial code Arenaflow{trademark}.

  12. Development of controlled release captopril granules coated with ethylcellulose and methylcellulose by fluid bed dryer.

    PubMed

    Stulzer, Hellen Karine; Silva, Marcos Antonio Segatto; Fernandes, Daniel; Assreuy, Jamil

    2008-01-01

    Captopril granules of controlled release with different polymers as ethylcellulose, ethyl/methylcellulose, and immediate release with polyvinylpyrrolidone (PVP) were developed by fluid bed dryer technique. The formulations were analyzed by scanning electron microscopy, X-ray powder diffraction, and dissolution profiles. To compare the formulations an in vivo setting rat blood pressure assay was performed, using angiotensin I as a vasoconstrictor agent. The scanning electron microscopy of granules showed differences in morphology, and X-ray powder diffraction technique presented some modification in crystalline structure of captopril in granules coated with PVP and ethyl/methylcellulose. The dissolution profile of granules coated with ethylcellulose showed a median time release of 4 hr whereas for granules coated with ethyl/methylcellulose, this time was 3.5 hr. The blockage of angiotensin I-induced hypertensive effect lasted 8 hr in granules coated with PVP and of more than 12 hr in the granules coated with ethylcellulose and ethyl/methylcellulose.

  13. The characterization of fluidization behavior using a novel multichamber microscale fluid bed.

    PubMed

    Räsänen, Eetu; Rantanen, Jukka; Mannermaa, Jukka-Pekka; Yliruusi, Jouko

    2004-03-01

    In the preformulation stage, there is a special need to determine the process behavior of materials with smaller amounts of samples. The purpose of this study was to assemble a novel automated multichamber microscale fluid bed module with a process air control unit for the characterization of fluidization behavior in variable conditions. The results were evaluated on the basis of two common computational methods, the minimum fluidization velocity, and the Geldart classification. The materials studied were different particle sizes of glass beads, microcrystalline cellulose, and silicified microcrystalline cellulose. During processing, the different characteristic fluidization phases (e.g., plugging, bubbling, slugging, and turbulent fluidization) of the materials were observed by the pressure difference over the bed. When the moisture content of the process air was increased, the amount of free charge carriers increased and the fine glass beads fluidized on the limited range of velocity. The silicification was demonstrated to improve the fluidization behavior with two different particle sizes of cellulose powders. Due to the interparticle (e.g., electrostatic) forces of the fine solids, the utilization of the computational predictions was restricted. The presented setup is a novel approach for studying process behavior with only a few grams of materials.

  14. An active particle in a complex fluid

    NASA Astrophysics Data System (ADS)

    Datt, Charu; Natale, Giovanniantonio; Hatzikiriakos, Savvas G.; Elfring, Gwynn J.

    2016-11-01

    Active particles are self-driven units capable of converting stored or ambient free-energy into systematic movement. We discuss here the case when such particles move through non-Newtonian fluids. Neglecting inertial forces, we employ the reciprocal theorem to calculate the propulsion velocity of a single swimmer in a weakly non-Newtonian fluid with background flow. We also derive a general expression for the velocity of an active particle modelled as a squirmer in a second-order fluid. We then discuss how active colloids are affected by the medium rheology, namely viscoelasticity and shear-thinning.

  15. Coupled dynamics of interfacial waves and bed forms in fluid muds over erodible seabeds in oscillatory flows

    NASA Astrophysics Data System (ADS)

    Trowbridge, J. H.; Traykovski, P.

    2015-08-01

    Recent field investigations of the damping of ocean surface waves over fluid muds have revealed waves on the interface between the thin layer of fluid mud and the overlying much thicker column of clear water, accompanied by bed forms on the erodible seabed beneath the fluid mud. The frequencies and wavelengths of the observed interfacial waves are qualitatively consistent with the linear dispersion relationship for long interfacial waves, but the forcing mechanism is not known. To understand the forcing, a linear model is proposed, based on the layer-averaged hydrostatic equations for the fluid mud, together with the Meyer-Peter-Mueller equation for the sediment transport within the underlying seabed, both subject to oscillatory forcing by the surface waves. If the underlying seabed is nonerodible and flat, the model indicates parametric instability to interfacial waves, but the threshold for instability is not met by the observations. If the underlying seabed is erodible, the model indicates that perturbations to the seabed elevation in the presence of the oscillatory forcing create interfacial waves, which in turn produce stresses within the fluid mud that force a net transport of sediment within the seabed toward the bed form crests, thus causing growth of both bed forms and interfacial waves. The frequencies, wavelengths, and growth rates are in qualitative agreement with the observations. A competition between mixing created by the interfacial waves and gravitational settling might control the thickness, density, and viscosity of the fluid muds during periods of strong forcing.

  16. The origin of fluids in the salt beds of the Delaware Basin, New Mexico and Texas

    USGS Publications Warehouse

    O'Neil, J.R.; Johnson, C.M.; White, L.D.; Roedder, E.

    1986-01-01

    Oxygen and hydrogen isotope analyses have been made of (1) brines from several wells in the salt deposits of the Delaware Basin, (2) inclusion fluids in halite crystals from the ERDA No. 9 site, and (3) local ground waters of meteoric origin. The isotopic compositions indicate that the brines are genetically related and that they probably originated from the evaporation of paleo-ocean waters. Although highly variable in solute contents, the brines have rather uniform isotopic compositions. The stable isotope compositions of brine from the ERDA No. 6 site (826.3 m depth) and fluid inclusions from the ERDA No. 9 site are variable but remarkably regular and show that (1) mixing with old or modern meteoric waters has occurred, the extent of mixing apparently decreasing with depth, and (2) water in the ERDA No. 6 brine may have originated from the dehydration of gypsum. Alternatively, the data may reflect simple evaporation of meteoric water on a previously dry marine flat. Stable isotope compositions of all the waters analyzed indicate that there has been fairly extensive mixing with ground water throughout the area, but that no significant circulation has occurred. The conclusions bear importantly on the suitability of these salt beds and others as repositories for nuclear waste. ?? 1986.

  17. Application of in-line near infrared spectroscopy and multivariate batch modeling for process monitoring in fluid bed granulation.

    PubMed

    Kona, Ravikanth; Qu, Haibin; Mattes, Robert; Jancsik, Bela; Fahmy, Raafat M; Hoag, Stephen W

    2013-08-16

    Fluid bed is an important unit operation in pharmaceutical industry for granulation and drying. To improve our understanding of fluid bed granulation, in-line near infrared spectroscopy (NIRS) and novel environmental temperature and RH data logger called a PyroButton(®) were used in conjunction with partial least square (PLS) and principal component analysis (PCA) to develop multivariate statistical process control charts (MSPC). These control charts were constructed using real-time moisture, temperature and humidity data obtained from batch experiments. To demonstrate their application, statistical control charts such as Scores, Distance to model (DModX), and Hotelling's T(2) were used to monitor the batch evolution process during the granulation and subsequent drying phase; moisture levels were predicted using a validated PLS model. Two data loggers were placed one near the bottom of the granulator bowl plenum where air enters the granulator and another inside the granulator in contact with the product in the fluid bed helped to monitor the humidity and temperature levels during the granulation and drying phase. The control charts were used for real time fault analysis, and were tested on normal batches and on three batches which deviated from normal processing conditions. This study demonstrated the use of NIRS and the use of humidity and temperature data loggers in conjunction with multivariate batch modeling as an effective tool in process understanding and fault determining method to effective process control in fluid bed granulation.

  18. Preliminary evaluation of coal-fired fluid bed combustion-augmented compressed air energy storage power plants

    NASA Astrophysics Data System (ADS)

    Lessard, R. D.; Giramonti, A. J.; Merrick, D.

    1980-03-01

    This paper presents highlights of an ongoing study program to assess the technical and economic feasibility of advanced concepts for generating peak-load electric power from a compressed air energy storage (CAES) power plant incorporating a coal-fired fluid bed combustor (FBC). It reviews the analyses performed to select an FBC/CAES power plant system configuration for the subsequent conceptual design phase of the study. Included in this review are: the design and operating considerations involved with integrating either an atmospheric or a pressurized fluid bed combustor with a CAES system to yield practical system configurations; the integration of system configurations; the parametric performance of these system configurations; and the preliminary screening which considered performance, cost, and technical risk and led to the identification of an open-bed PFBC/CAES system as having the greatest near-term commercialization potential.

  19. Dynamic Patterns in Active Fluids

    NASA Astrophysics Data System (ADS)

    Jülicher, Frank

    2012-02-01

    Biological matter is inherently dynamic and exhibits active properties. A key example is the force generation by molecular motors in the cell cytoskeleton. Such active processes give rise to the generation of active mechanical stresses and spontaneous flows in gel-like cytoskeletal networks. Active material behaviors play a key role for the dynamics of cellular processes such as cell locomotion and cell division. We will discuss intracellular flow patterns that are created by active processes in the cell cortex. By combining theory with quantitative experiments we show that observed flow patterns result from profiles of active stress generation in the system. We will also consider the situation where active stress is regulated by a diffusing molecular species. In this case, spatial concentration patterns are generated by the interplay of stress regulation and self-generated flow fields.

  20. Optimization and scale-up of oligonucleotide synthesis in packed bed reactors using computational fluid dynamics modeling.

    PubMed

    Wolfrum, Christian; Josten, Andre; Götz, Peter

    2014-01-01

    A computational fluid dynamics (CFD) model for the analysis of oligonucleotide synthesis in packed bed reactors was developed and used to optimize the scale up of the process. The model includes reaction kinetics data obtained under well defined conditions comparable to the situation in the packed bed. The model was validated in terms of flow conditions and reaction kinetics by comparison with experimental data. Experimental validation and the following model parameter studies by simulation were performed on the basis of a column with 0.3 g oligonucleotide capacity. The scale-up studies based on CFD modelling were calculated on a 440 g scale (oligonucleotide capacity).

  1. Optimization and scale-up of a fluid bed tangential spray rotogranulation process.

    PubMed

    Bouffard, J; Dumont, H; Bertrand, F; Legros, R

    2007-04-20

    The production of pellets in the pharmaceutical industry generally involves multi-step processing: (1) mixing, (2) wet granulation, (3) spheronization and (4) drying. While extrusion-spheronization processes have been popular because of their simplicity, fluid-bed rotogranulation (FBRG) is now being considered as an alternative, since it offers the advantages of combining the different steps into one processing unit, thus reducing processing time and material handling. This work aimed at the development of a FBRG process for the production of pellets in a 4.5-l Glatt GCPG1 tangential spray rotoprocessor and its optimization using factorial design. The factors considered were: (1) rotor disc velocity, (2) gap air pressure, (3) air flow rate, (4) binder spray rate and (5) atomization pressure. The pellets were characterized for their physical properties by measuring size distribution, roundness and flow properties. The results indicated that: pellet mean particle size is negatively affected by air flow rate and rotor plate speed, while binder spray rate has a positive effect on size; pellet flow properties are enhanced by operating with increased air flow rate and worsened with increased binder spray rate. Multiple regression analysis enabled the identification of an optimal operating window for production of acceptable pellets. Scale-up of these operating conditions was tested in a 30-l Glatt GPCG15 FBRG.

  2. A quality by design study applied to an industrial pharmaceutical fluid bed granulation.

    PubMed

    Lourenço, Vera; Lochmann, Dirk; Reich, Gabriele; Menezes, José C; Herdling, Thorsten; Schewitz, Jens

    2012-06-01

    The pharmaceutical industry is encouraged within Quality by Design (QbD) to apply science-based manufacturing principles to assure quality not only of new but also of existing processes. This paper presents how QbD principles can be applied to an existing industrial pharmaceutical fluid bed granulation (FBG) process. A three-step approach is presented as follows: (1) implementation of Process Analytical Technology (PAT) monitoring tools at the industrial scale process, combined with multivariate data analysis (MVDA) of process and PAT data to increase the process knowledge; (2) execution of scaled-down designed experiments at a pilot scale, with adequate PAT monitoring tools, to investigate the process response to intended changes in Critical Process Parameters (CPPs); and finally (3) the definition of a process Design Space (DS) linking CPPs to Critical to Quality Attributes (CQAs), within which product quality is ensured by design, and after scale-up enabling its use at the industrial process scale. The proposed approach was developed for an existing industrial process. Through enhanced process knowledge established a significant reduction in product CQAs, variability already within quality specifications ranges was achieved by a better choice of CPPs values. The results of such step-wise development and implementation are described.

  3. Bench-scale studies on fluid-bed pyrolysis of wood

    SciTech Connect

    Mudge, L.K.; Brown, M.D.; Wilcox, W.A.

    1988-08-01

    The primary objective of this study was to determine the effects of different contact gases and experimental conditions on product yields from fluid-bed wood pyrolysis. The yield of condensible hydrocarbons was of particular interest. The contact gases employed included carbon dioxide (CO/sub 2/), methane (CH/sub 4/), and hydrogen (H/sub 2/). Reaction temperatures ranged from 650/degree/C to 800/degree/C, and gas contact time was between 1 and 2 s. Tests with CO/sub 2/ contact gas used a secondary vessel of catalyst for cracking of condensibles generated in the primary gasifier. Results of earlier studies at PNL showed the effectiveness of various catalysts for destruction of condensible hydrocarbons. Analyses of results on the effects of contact gas, reaction temperature, gas contact time, and wood feed rate are presented in this report, along with a description of experimental equipment and methods. Data were obtained from single tests at each set of experimental conditions. Conditions were not repeated to determine the amount of experimental error. Material balance closures were generally quite good for the experimental tests, within 10%. 9 refs., 15 figs., 16 tabs.

  4. Design Space Approach in Optimization of Fluid Bed Granulation and Tablets Compression Process

    PubMed Central

    Djuriš, Jelena; Medarević, Djordje; Krstić, Marko; Vasiljević, Ivana; Mašić, Ivana; Ibrić, Svetlana

    2012-01-01

    The aim of this study was to optimize fluid bed granulation and tablets compression processes using design space approach. Type of diluent, binder concentration, temperature during mixing, granulation and drying, spray rate, and atomization pressure were recognized as critical formulation and process parameters. They were varied in the first set of experiments in order to estimate their influences on critical quality attributes, that is, granules characteristics (size distribution, flowability, bulk density, tapped density, Carr's index, Hausner's ratio, and moisture content) using Plackett-Burman experimental design. Type of diluent and atomization pressure were selected as the most important parameters. In the second set of experiments, design space for process parameters (atomization pressure and compression force) and its influence on tablets characteristics was developed. Percent of paracetamol released and tablets hardness were determined as critical quality attributes. Artificial neural networks (ANNs) were applied in order to determine design space. ANNs models showed that atomization pressure influences mostly on the dissolution profile, whereas compression force affects mainly the tablets hardness. Based on the obtained ANNs models, it is possible to predict tablet hardness and paracetamol release profile for any combination of analyzed factors. PMID:22919295

  5. Antibacterial activity of the pancreatic fluid.

    PubMed

    Rubinstein, E; Mark, Z; Haspel, J; Ben-Ari, G; Dreznik, Z; Mirelman, D; Tadmor, A

    1985-04-01

    The antibacterial activity of canine pancreatic fluid was investigated in an attempt to understand the resistance of this organ, when intact, to ascending bacterial infections. The pancreatic fluid demonstrated bactericidal activity against Escherichia coli, Shigella species, Salmonella species, and Klebsiella pneumoniae; bacteriostatic activity against coagulase-positive and coagulase-negative staphylococci and Pseudomonas aeruginosa; and fungistatic activity against Candida albicans. There was no demonstrable antibacterial activity against Bacteroides fragilis and Streptococcus faecalis. The antibacterial activity was dialyzable and pH dependent, but independent of heat, the activity of several digestive pancreatic enzymes, and the bacterial inoculum. Electron micrographs of Escherichia coli exposed to pancreatic fluid did not demonstrate changes in the bacterial cell wall. Tracer studies of susceptible bacteria demonstrated decreased leucine uptake when briefly exposed to pancreatic fluid. The antibacterial activity was found by column chromatography to be a small molecular peptide. It is likely that pancreatic antibacterial factors protect the pancreas from ascending bacterial infections and operate along with other factors in the homeostasis of the upper small bowel flora.

  6. Cardiovascular and Body Fluid Adjustments During Bed Rest and Space Flight

    NASA Technical Reports Server (NTRS)

    Greenleaf, John E.; Tomko, David L. (Technical Monitor)

    1995-01-01

    Although a few scientific bed rest (BR) studies were conducted soon after World War II, advent of the space program provided impetus for utilizing prolonged (days-months) BR, which employed the horizontal or 6 degree head-down tilt (HDT) body positions, to simulate responses of healthy people to microgravity. Shorter (hours) HDT protocols were used to study initial mechanisms of the acclimation-deconditioning (reduction of physical fitness) syndromes. Of the major physiological factors modified during BR, reduced force on bones, ligaments, and muscles, and greatly reduced hydrostatic pressure within the cardiovascular system, the latter: which involves shifts of blood from the lower extremities into the upper body, increase in central venous pressure, and diuresis, appears to be the initial stimulus for acclimation. Increase in central venous pressure occurs in subjects during weightless parabolic flight, but not in astronauts early during orbital flight. But significant reduction in total body water (hypohydration) and plasma volume (hypovolemia) occurs in subjects during both BR and microgravity. Response of interstitial fluid volume is not as clear, It has been reported to increase during BR, and it may have increased in Skylab II and IV astronauts. Reduction of total body water, and greater proportional reduction of extracellular volume, indicates increased cellular volume which may contribute to inflight cephalic edema. Cerebral pressure abates after a few days of HDT, but not during flight. accompanied by normal (eugravity) blood constituent concentrations suggesting some degree of acclimation had occurred. But during reentry, with moderately increased +Gz (head-to-foot) acceleration and gravitational force, the microgravity "euhydration" becomes functional progressive dehydration contributing to the general reentry syndrome (GRS) which, upon landing the Shuttle, can and often results in gastrointestinal distress, disorientation, vertigo, fatigue, and

  7. Fluid and electrolyte shifts in women during +Gz acceleration after 15 days' bed rest

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Stinnett, H. O.; Davis, G. L.; Kollias, J.; Bernauer, E. M.

    1977-01-01

    Experiments were conducted on twelve women aged 23-34 yr - a bed rest (BR) group of eight subjects and an ambulatory (AMB) group of four subjects - to determine the effect of bed rest on shifts in plasma volume, electrolytes, and erythrocyte volume during +Gz acceleration on a centrifuge. The BR group underwent the +Gz acceleration during a two-week ambulatory control period, after 15 days of a 17-day BR period, and on the third day of ambulatory recovery. The AMB group underwent the same experimental procedures, but continued their normal daily routine during the BR period without additional prescribed physical exercise. Major conclusions are that (1) the higher the mean control tolerance, the greater the tolerance decline after BR; (2) relative confinement and reduced activity contribute as much to reduction in tolerance as does the horizontal body position during BR; (3) BR deconditioning has no effect on the erythrocyte volume during +3.0 Gz; and (4) about one-half the loss in tolerance after BR can be attributed to plasma volume and electrolyte shifts.

  8. Fluid bed gasification – Plasma converter process generating energy from solid waste: Experimental assessment of sulphur species

    SciTech Connect

    Morrin, Shane; Lettieri, Paola; Chapman, Chris; Taylor, Richard

    2014-01-15

    Highlights: • We investigate gaseous sulphur species whilst gasifying sulphur-enriched wood pellets. • Experiments performed using a two stage fluid bed gasifier – plasma converter process. • Notable SO{sub 2} and relatively low COS levels were identified. • Oxygen-rich regions of the bed are believed to facilitate SO{sub 2}, with a delayed release. • Gas phase reducing regions above the bed would facilitate more prompt COS generation. - Abstract: Often perceived as a Cinderella material, there is growing appreciation for solid waste as a renewable content thermal process feed. Nonetheless, research on solid waste gasification and sulphur mechanisms in particular is lacking. This paper presents results from two related experiments on a novel two stage gasification process, at demonstration scale, using a sulphur-enriched wood pellet feed. Notable SO{sub 2} and relatively low COS levels (before gas cleaning) were interesting features of the trials, and not normally expected under reducing gasification conditions. Analysis suggests that localised oxygen rich regions within the fluid bed played a role in SO{sub 2}’s generation. The response of COS to sulphur in the feed was quite prompt, whereas SO{sub 2} was more delayed. It is proposed that the bed material sequestered sulphur from the feed, later aiding SO{sub 2} generation. The more reducing gas phase regions above the bed would have facilitated COS – hence its faster response. These results provide a useful insight, with further analysis on a suite of performed experiments underway, along with thermodynamic modelling.

  9. Integrated low emissions cleanup system for direct coal fueled turbines (moving bed, fluid bed contactor/ceramic filter)

    SciTech Connect

    Newby, R.A.; Alvin, M.A.; Bachovchin, D.M.; Yang, W.C.; Smeltzer, E.E.; Lippert, T.E.

    1992-10-20

    The United States Department of Energy, Morgantown Energy Research Center (DOE/METC), is sponsoring the development of direct coal-fired turbine power plants as part of their Heat Engines program. A major technical challenge remaining for the development of the direct coal-fired turbine is high-temperature combustion gas cleaning to meet environmental standards for sulfur oxides and particulate emissions, as well as to provide acceptable turbine life. The Westinghouse Electric Corporation, Science Technology Center, is evaluating two Integrated Low Emissions Cleanup (ILEC) concepts that have been configured to meat this technical challenge: a baseline ceramic barrier filter ILEC concept, and a fluidized bed ILEC concept. These ILEC concepts simultaneously control sulfur, particulate, and alkali contaminants in the high-pressure combustion gases at turbine inlet temperatures up to 2300[degree]F. This document reports the status of a program in the nineteenth quarter to develop this ILEC technology for direct coal-fired turbine power plants.

  10. Study of ebullated bed fluid dynamics for H-Coal. Quarterly progress report No. 1, July 1-September 30, 1980

    SciTech Connect

    Schaefer, R. J.; Rundell, D. N.

    1980-12-01

    Cold flow experiments were completed with kerosene, nitrogen, and HDS-2A (3/16'' length) catalyst. Percent bed expansion, gas/liquid/catalyst holdups, and drift fluxes were determined for each test. Fluid dynamics data were obtained at HRI during Run PDU-10 (Wyodak coal and Amocat-1A catalyst). Reactor liquid samples were taken for later viscosity determination. A 6'' diameter test stand for bubble coalescence experiments was constructed and delivered to Northwestern University. A search was initiated to select suitable model fluids.

  11. Particle size, moisture, and fluidization variations described by indirect in-line physical measurements of fluid bed granulation.

    PubMed

    Lipsanen, Tanja; Närvänen, Tero; Räikkönen, Heikki; Antikainen, Osmo; Yliruusi, Jouko

    2008-01-01

    The aim of this study was to evaluate an instrumentation system for a bench scale fluid bed granulator to determine the parameters expressing the changing conditions during the spraying phase of a fluid bed process. The study focused mainly on four in-line measurements (dependent variables): fluidization parameter (calculated by inlet air flow rate and rotor speed), pressure difference over the upper filters, pressure difference over the granules (lower filter), and temperature of the fluidizing mass. In-line particle size measured by the spatial filtering technique was an essential predictor variable. Other physical process measurements of the automated granulation system, 25 direct and 12 derived parameters, were also utilized for multivariate modeling. The correlation and partial least squares analyses revealed significant relationships between various process parameters highlighting the particle size, moisture, and fluidization effect. Fluidization parameter and pressure difference over upper filters were found to correlate with in-line particle size and therefore could be used as estimates of particle size during granulation. The pressure difference over the granules and the temperature of the fluidizing mass expressed the moisture conditions of wet granulation. The instrumentation system evaluated here is an invaluable aid to gaining more control for fluid bed processing to obtain repeatable granules for further processing.

  12. In-line monitoring of particle size in a fluid bed granulator: investigations concerning positioning and configuration of the sensor.

    PubMed

    Roßteuscher-Carl, Katrin; Fricke, Sabine; Hacker, Michael C; Schulz-Siegmund, Michaela

    2014-05-15

    According to the ICH Q8 guideline, analytic technologies (PAT) are important tools for characterization and optimization of pharmaceutical manufacturing processes. Particle size as a critical quality attribute for granules is therefore an important parameter that should be monitored during the fluid bed granulation process. This work focusses on optimizing position and configuration of an SFT-sensor for the in-line measurement of particle size distribution in a Glatt GPCG 3 fluid bed granulator. As model-substances, different grades of microcrystalline cellulose were used. The in-line measured particle size and particle rate in the sensor were evaluated. A sensor position in the deceleration zone of the granulator was found to be promising for in-line particle size measurement. Most reliable data were generated in this position when the probe was placed in a distance of 11cm from the chamber wall to avoid bias by the inlet air stream. No major influence of rotation angle of the probe was found in this position. Furthermore, an entire fluid bed granulation process was successfully monitored with the sensor installed in the optimized setting.

  13. Microwave drying of granules containing a moisture-sensitive drug: a promising alternative to fluid bed and hot air oven drying.

    PubMed

    Chee, Sze Nam; Johansen, Anne Lene; Gu, Li; Karlsen, Jan; Heng, Paul Wan Sia

    2005-07-01

    The impact of microwave drying and binders (copolyvidone and povidone) on the degradation of acetylsalicylic acid (ASA) and physical properties of granules were compared with conventional drying methods. Moist granules containing ASA were prepared using a high shear granulator and dried with hot air oven, fluid bed or microwave (static or dynamic bed) dryers. Percent ASA degradation, size and size distribution, friability and flow properties of the granules were determined. Granules dried with the dynamic bed microwave dryer showed the least amount of ASA degradation, followed by fluid bed dryer, static bed microwave oven and hot air oven. The use of microwave drying with a static granular bed adversely affected ASA degradation and drying capability. Dynamic bed microwave dryer had the highest drying capability followed by fluid bed, static bed microwave dryer and conventional hot air oven. The intensity of microwave did not affect ASA degradation, size distribution, friability and flow properties of the granules. Mixing/agitating of granules during drying affected the granular physical properties studied. Copolyvidone resulted in lower amount of granular residual moisture content and ASA degradation on storage than povidone, especially for static bed microwave drying. In conclusion, microwave drying technology has been shown to be a promising alternative for drying granules containing a moisture-sensitive drug.

  14. Microencapsulation of fish oil by spray granulation and fluid bed film coating.

    PubMed

    Anwar, Sri Haryani; Weissbrodt, Jenny; Kunz, Benno

    2010-08-01

    The stability of microencapsulated fish oil prepared with 2 production processes, spray granulation (SG) and SG followed by film coating (SG-FC) using a fluid bed equipment, was investigated. In the 1st process, 3 types of fish oil used were based on the ratios of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (10/50, 33/22, and 18/12). Each type was emulsified with soluble soybean polysaccharide (SSPS) and maltodextrin to produce 25% oil powders. In the 2nd process, 15% film coating of hydroxypropyl betacyclodextrin (HPBCD) was applied to the granules from the 1st process. The powder stability against oxidation was examined by measurement of peroxide values (PV) and headspace propanal after storage at room temperature and at 3 to 4 degrees C for 6 wk. Uncoated powder containing the lowest concentration of PUFA (18/12) was found to be stable during storage at room temperature with maximum PV of 3.98 +/- 0.001 meq/kg oil. The PV increased sharply for uncoated powder with higher concentration of omega-3 (in 33/22 and 10/50 fish oils) after 3 wk storage. The PVs were in agreement with the concentration of propanal, and these 2 parameters remained constant for most of the uncoated powders stored at low temperature. Unexpectedly, the outcomes showed that the coated powders had lower stability than uncoated powders as indicated by higher initial PVs; more hydroperoxides were detected as well as increasing propanal concentration. The investigation suggests that the film-coating by HPBCD ineffectively protected fish oil as the coating process might have induced further oxidation; however, SG is a good method for producing fish oil powder and to protect it from oxidation because of the "onion skin" structure of granules produced in this process.

  15. From pore-scale flow measurements towards a Computational Fluid Dynamics prediction of momentum exchange across river bed interface

    NASA Astrophysics Data System (ADS)

    Sambrook Smith, G.; Hardy, R. J.; Best, J.; Blois, G.; Lead, J.

    2010-12-01

    Developing numerical models capable of simulating the hydrodynamics of open-channel flows over rough and within permeable beds is crucial for predicting the morphodynamic evolution of alluvial channels, as well as understanding the complex physical-chemical processes occurring within the subsurface (hyporheic zone) of river beds. However, most current numerical models assume that alluvial streams have an impermeable channel bed, which represents a considerable simplification since experimental observations have shown turbulence within gravel-beds can be significant. Thus, Darcian theory, suitable for low-conductivity porous media, should not be applied within cohesionless gravel-bed rivers. Although the Reynolds Averaged Navier Stokes (RANS) equations can be used to model flow through a porous media if the internal morphology is known, this has rarely been accomplished, and the complexity of the internal morphology of the bed has meant that the normal approach to this problem is to volume-average the NS equations and close them with the Hazen-Dupui-Darcy (HDD) model. However, if the internal morphology of the bed is known a Computational Fluid Dynamics (CFD) approach with a mass flux scaling algorithm (MFSA), which has been developed to include complex bed topography into a numerically stable discretization, can be applied. This allows both time averaged, and time dependent prediction of the flow. Even though these models represent the state-of-the-art, they have yet to be validated, and hence their reliability remains unknown. The lack of appropriate validation data is due to the fact that experimental techniques cannot currently meet the significant challenges required to fully characterize the complex instantaneous turbulent patterns produced within bed pore spaces. To meet this challenge, a novel high-resolution endoscopic particle image velocimetry (E-PIV) technique, capable of collecting data within the pore spaces of a submerged permeable bed, has been

  16. Activity of anandamide (AEA) metabolic enzymes in rat placental bed.

    PubMed

    Fonseca, B M; Battista, N; Correia-da-Silva, G; Rapino, C; Maccarrone, M; Teixeira, N A

    2014-11-01

    Endocannabinoids are endogenous lipid mediators, with anandamide (AEA) being the first member identified. It is now widely accepted that AEA influences early pregnancy events and its levels, which primarily depend on its synthesis by an N-acyl-phosphatidylethanolamine-specific phospholipase D (NAPE-PLD) and degradation by a fatty acid amide hydrolase (FAAH), must be tightly regulated. Previous studies demonstrated that AEA levels require in situ regulation of these respective metabolic enzymes, and thus, any disturbance in AEA levels may impact maternal remodeling processes occurring during placental development. In this study, the activities of the AEA-metabolic enzymes that result in the establishment of proper local AEA levels during rat gestation were examined. Here, we demonstrate that during placentation NAPE-PLD and FAAH activities change in a temporal manner. Our findings suggest that NAPE-PLD and FAAH create the appropriate AEA levels required for tissue remodeling in the placental bed, a process essential to pregnancy maintenance.

  17. Quantifying fluid and bed dynamics for characterizing benthic physical habitat in large rivers

    USGS Publications Warehouse

    Gaeuman, D.; Jacobson, R.B.

    2007-01-01

    Sturgeon use benthic habitats in and adjacent to main channels where environmental conditions can include bedload sediment transport and high near-bed flow velocities. Bed velocity measurements obtained with acoustic Doppler instruments provide a means to assess the concentration and velocity of sediment moving near the streambed, and are thus indicative of the bedload sediment transport rate, the near-bed flow velocity, and the stability of the substrate. Acoustic assessments of benthic conditions in the Missouri River were conducted at scales ranging from the stream reach to individual bedforms. Reach-scale results show that spatially-averaged bed velocities in excess of 0.5 m s-1 frequently occur in the navigation channel. At the local scale, bed velocities are highest near bedform crests, and lowest in the troughs. Low-velocity zones can persist in areas with extremely high mean bed velocities. Use of these low-velocity zones may allow sturgeon to make use of portions of the channel where the average conditions near the bed are severe. To obtain bed velocity measurements of the highest possible quality, it is necessary to extract bottom-track and GPS velocity information from the raw ADCP data files on a ping-by-ping basis. However, bed velocity measured from a point can also be estimated using a simplified method that is more easily implemented in the context of routine monitoring. The method requires only the transect distance and direction data displayed in standard ADCP data-logging software. Bed velocity estimates obtained using this method are usually within 5-10% of estimates obtained from ping-by-ping processing. ?? 2007 Blackwell Verlag.

  18. Dynamic adsorption of organic solvent vapors onto a packed bed of activated carbon cloth

    SciTech Connect

    Huang, C.C.; Lin, Y.C.; Lu, F.C.

    1999-02-01

    The adsorption behavior of organic compound vapors onto a packed bed of activated carbon cloth (ACC) has been investigated. Three types of ACCs have been employed: KF1500, FT200-20, and E-ACC. The volatile organic compounds (VOCs) used in this study are acetone, dichloromethane, acrylonitrile, and n-hexane. The operating parameters studied are temperature of adsorber, weight of ACC, relative humidity of fluid, inlet concentration of VOCs, and total volumetric flow rate of gas stream. A simple theoretical model, originally introduced by Yoon and Nelson, has been utilized to simulate the breakthrough curve of VOC vapor on an adsorption column packed with activated carbon cloth. A modified model is proposed to predict the adsorption behavior of an adsorber at different temperatures.

  19. Meandering instability of air flow in a granular bed: self-similarity and fluid-solid duality

    PubMed Central

    Yoshimura, Yuki; Yagisawa, Yui; Okumura, Ko

    2016-01-01

    Meandering instability is familiar to everyone through river meandering or small rivulets of rain flowing down a windshield. However, its physical understanding is still premature, although it could inspire researchers in various fields, such as nonlinear science, fluid mechanics and geophysics, to resolve their long-standing problems. Here, we perform a small-scale experiment in which air flow is created in a thin granular bed to successfully find a meandering regime, together with other remarkable fluidized regimes, such as a turbulent regime. We discover that phase diagrams of the flow regimes for different types of grains can be universally presented as functions of the flow rate and the granular-bed thickness when the two quantities are properly renormalized. We further reveal that the meandering shapes are self-similar as was shown for meandering rivers. The experimental findings are explained by theory, with elucidating the physics. The theory is based on force balance, a minimum-dissipation principle, and a linear-instability analysis of a continuum equation that takes into account the fluid-solid duality, i.e., the existence of fluidized and solidified regions of grains along the meandering path. The present results provide fruitful links to related issues in various fields, including fluidized bed reactors in industry. PMID:27941823

  20. Meandering instability of air flow in a granular bed: self-similarity and fluid-solid duality.

    PubMed

    Yoshimura, Yuki; Yagisawa, Yui; Okumura, Ko

    2016-12-12

    Meandering instability is familiar to everyone through river meandering or small rivulets of rain flowing down a windshield. However, its physical understanding is still premature, although it could inspire researchers in various fields, such as nonlinear science, fluid mechanics and geophysics, to resolve their long-standing problems. Here, we perform a small-scale experiment in which air flow is created in a thin granular bed to successfully find a meandering regime, together with other remarkable fluidized regimes, such as a turbulent regime. We discover that phase diagrams of the flow regimes for different types of grains can be universally presented as functions of the flow rate and the granular-bed thickness when the two quantities are properly renormalized. We further reveal that the meandering shapes are self-similar as was shown for meandering rivers. The experimental findings are explained by theory, with elucidating the physics. The theory is based on force balance, a minimum-dissipation principle, and a linear-instability analysis of a continuum equation that takes into account the fluid-solid duality, i.e., the existence of fluidized and solidified regions of grains along the meandering path. The present results provide fruitful links to related issues in various fields, including fluidized bed reactors in industry.

  1. Meandering instability of air flow in a granular bed: self-similarity and fluid-solid duality

    NASA Astrophysics Data System (ADS)

    Yoshimura, Yuki; Yagisawa, Yui; Okumura, Ko

    2016-12-01

    Meandering instability is familiar to everyone through river meandering or small rivulets of rain flowing down a windshield. However, its physical understanding is still premature, although it could inspire researchers in various fields, such as nonlinear science, fluid mechanics and geophysics, to resolve their long-standing problems. Here, we perform a small-scale experiment in which air flow is created in a thin granular bed to successfully find a meandering regime, together with other remarkable fluidized regimes, such as a turbulent regime. We discover that phase diagrams of the flow regimes for different types of grains can be universally presented as functions of the flow rate and the granular-bed thickness when the two quantities are properly renormalized. We further reveal that the meandering shapes are self-similar as was shown for meandering rivers. The experimental findings are explained by theory, with elucidating the physics. The theory is based on force balance, a minimum-dissipation principle, and a linear-instability analysis of a continuum equation that takes into account the fluid-solid duality, i.e., the existence of fluidized and solidified regions of grains along the meandering path. The present results provide fruitful links to related issues in various fields, including fluidized bed reactors in industry.

  2. Oxygen consumption by a sediment bed for stagnant water: comparison to SOD with fluid flow.

    PubMed

    Higashino, Makoto

    2011-10-01

    A model of sedimentary oxygen demand (SOD) for stagnant water in a lake or a reservoir is presented. For the purposes of this paper, stagnant water is defined as the bottom layer of stratified water columns in relatively unproductive systems that are underlain by silt and sand-dominated sediments with low-organic carbon (C) and nitrogen (N). The modeling results are compared to those with fluid flow to investigate how flow over the sediment surface raises SOD compared to stagnant water, depending on flow velocity and biochemical activity in the sediment. SOD is found to be substantially limited by oxygen transfer in the water column when water is stagnant. When flow over the sediment surface is present, SOD becomes larger than that for stagnant water, depending on flow velocity and the biochemical oxygen uptake rate in the sediment. Flow over the sediment surface causes an insignificant raise in SOD when the biochemical oxygen uptake rate is small. The difference between SOD with fluid flow and SOD for stagnant water becomes significant as the biochemical oxygen uptake rate becomes larger, i.e. SOD is 10-100 times larger when flow over the sediment surface is present.

  3. Feel the heat: activation, orientation and feeding responses of bed bugs to targets at different temperatures.

    PubMed

    DeVries, Zachary C; Mick, Russell; Schal, Coby

    2016-12-01

    Host location in bed bugs is poorly understood. Of the primary host-associated cues known to attract bed bugs - CO2, odors, heat - heat has received little attention as an independent stimulus. We evaluated the effects of target temperatures ranging from 23 to 48°C on bed bug activation, orientation and feeding. Activation and orientation responses were assessed using a heated target in a circular arena. All targets heated above ambient temperature activated bed bugs (initiated movement) and elicited oriented movement toward the target, with higher temperatures generally resulting in faster activation and orientation. The distance over which bed bugs could orient toward a heat source was measured using a 2-choice T-maze assay. Positive thermotaxis was limited to distances <3 cm. Bed bug feeding responses on an artificial feeding system increased with feeder temperature up to 38 and 43°C, and declined precipitously at 48°C. In addition, bed bugs responded to the relative difference between ambient and feeder temperatures. These results highlight the wide range of temperatures that elicit activation, orientation and feeding responses in bed bugs. In contrast, the ability of bed bugs to correctly orient towards a heated target, independently of other cues, is limited to very short distances (<3 cm). Finally, bed bug feeding is shown to be relative to ambient temperature, not an absolute response to feeder blood temperature.

  4. Pattern formation in Active Polar Fluids

    NASA Astrophysics Data System (ADS)

    Gopinath, Arvind; Hagan, Michael; Baskaran, Aparna

    2011-03-01

    Systems such as bacterial suspensions or cytoskeletal filaments and motility assays can be described within the paradigm of active polar fluids. These systems have been shown to exhibit pattern formation raging from asters and vortices to traveling stripes. A coarse-grained description of such a fluid is given by a scalar density field and a vector polarization field. We study such a macroscopic description of the system using weakly nonlinear analysis and numerical simulations to map out the emergent pattern formation as a function of the hydrodynamic parameters in the context of two specific microscopic models - a quasi-2D suspension of cytoskeletal filaments and motor proteins and a system of self propelled hard rods that interact through excluded volume interactions. The authors thank the Brandeis MRSEC center for financial support.

  5. Dynamics and Emergent Structures in Active Fluids

    NASA Astrophysics Data System (ADS)

    Baskaran, Aparna

    2014-03-01

    In this talk, we consider an active fluid of colloidal sized particles, with the primary manifestation of activity being a self-replenishing velocity along one body axis of the particle. This is a minimal model for varied systems such as bacterial colonies, cytoskeletal filament motility assays vibrated granular particles and self propelled diffusophoretic colloids, depending on the nature of interaction among the particles. Using microscopic Brownian dynamics simulations, coarse-graining using the tools of non-equilibrium statistical mechanics and analysis of macroscopic hydrodynamic theories, we characterize emergent structures seen in these systems, which are determined by the symmetry of the interactions among the active units, such as propagating density waves, dense stationary bands, asters and phase separated isotropic clusters. We identify a universal mechanism, termed ``self-regulation,'' as the underlying physics that leads to these structures in diverse systems. Support from NSF through DMR-1149266 and DMR-0820492.

  6. Two-compartmental population balance modeling of a pulsed spray fluidized bed granulation based on computational fluid dynamics (CFD) analysis.

    PubMed

    Liu, Huolong; Li, Mingzhong

    2014-11-20

    In this work a two-compartmental population balance model (TCPBM) was proposed to model a pulsed top-spray fluidized bed granulation. The proposed TCPBM considered the spatially heterogeneous granulation mechanisms of the granule growth by dividing the granulator into two perfectly mixed zones of the wetting compartment and drying compartment, in which the aggregation mechanism was assumed in the wetting compartment and the breakage mechanism was considered in the drying compartment. The sizes of the wetting and drying compartments were constant in the TCPBM, in which 30% of the bed was the wetting compartment and 70% of the bed was the drying compartment. The exchange rate of particles between the wetting and drying compartments was determined by the details of the flow properties and distribution of particles predicted by the computational fluid dynamics (CFD) simulation. The experimental validation has shown that the proposed TCPBM can predict evolution of the granule size and distribution within the granulator under different binder spray operating conditions accurately.

  7. Fluid bed gasification--plasma converter process generating energy from solid waste: experimental assessment of sulphur species.

    PubMed

    Morrin, Shane; Lettieri, Paola; Chapman, Chris; Taylor, Richard

    2014-01-01

    Often perceived as a Cinderella material, there is growing appreciation for solid waste as a renewable content thermal process feed. Nonetheless, research on solid waste gasification and sulphur mechanisms in particular is lacking. This paper presents results from two related experiments on a novel two stage gasification process, at demonstration scale, using a sulphur-enriched wood pellet feed. Notable SO2 and relatively low COS levels (before gas cleaning) were interesting features of the trials, and not normally expected under reducing gasification conditions. Analysis suggests that localised oxygen rich regions within the fluid bed played a role in SO2's generation. The response of COS to sulphur in the feed was quite prompt, whereas SO2 was more delayed. It is proposed that the bed material sequestered sulphur from the feed, later aiding SO2 generation. The more reducing gas phase regions above the bed would have facilitated COS--hence its faster response. These results provide a useful insight, with further analysis on a suite of performed experiments underway, along with thermodynamic modelling.

  8. Performance improvement of a converted fluid bed boiler (from traveling grate type) for agro waste combustion -- A case study

    SciTech Connect

    Sethumadhavan, R.; Karthikeyan, G.; Raviprakash, A.V.; Vasudevan, R.

    1997-12-31

    This paper investigates the operational difficulty encountered while operating a fluid bed boiler--which was earlier serving with a traveling grate for agrowaste combustion. This boiler, although operating on fluid bed technology principle, could not produce required combustion efficiency while burning any of the agrowastes such as rice husk, de-oiled bran, ground nut shell, etc. While carrying out the performance assessment study, it was found that, this inefficient combustion was mainly due to the improper operating parameters and partly due to incorrect furnace configuration. The drawbacks of the system have been attended to and set right incurring a very minor expenditure. This has led to an annual fuel saving of approximately US $40,000. The major results achieved are: (1) boiler thermal efficiency increased from 66--73%; (2) boiler was loaded uniformly and on-time operation has increased to 100% from earlier 60%; (3) boiler shut down time due to operational problems has come down from 35 hours per month to 15 hours per month; (4) very effective dust collection system was achieved resulting in reduced ID fan erosion; and (5) an annual saving of US $100,000 (both direct and indirect) was achieved.

  9. New class of turbulence in active fluids.

    PubMed

    Bratanov, Vasil; Jenko, Frank; Frey, Erwin

    2015-12-08

    Turbulence is a fundamental and ubiquitous phenomenon in nature, occurring from astrophysical to biophysical scales. At the same time, it is widely recognized as one of the key unsolved problems in modern physics, representing a paradigmatic example of nonlinear dynamics far from thermodynamic equilibrium. Whereas in the past, most theoretical work in this area has been devoted to Navier-Stokes flows, there is now a growing awareness of the need to extend the research focus to systems with more general patterns of energy injection and dissipation. These include various types of complex fluids and plasmas, as well as active systems consisting of self-propelled particles, like dense bacterial suspensions. Recently, a continuum model has been proposed for such "living fluids" that is based on the Navier-Stokes equations, but extends them to include some of the most general terms admitted by the symmetry of the problem [Wensink HH, et al. (2012) Proc Natl Acad Sci USA 109:14308-14313]. This introduces a cubic nonlinearity, related to the Toner-Tu theory of flocking, which can interact with the quadratic Navier-Stokes nonlinearity. We show that as a result of the subtle interaction between these two terms, the energy spectra at large spatial scales exhibit power laws that are not universal, but depend on both finite-size effects and physical parameters. Our combined numerical and analytical analysis reveals the origin of this effect and even provides a way to understand it quantitatively. Turbulence in active fluids, characterized by this kind of nonlinear self-organization, defines a new class of turbulent flows.

  10. Behavioral Responses of the Bed Bug to Permethrin-Impregnated ActiveGuard™ Fabric

    PubMed Central

    Jones, Susan C.; Bryant, Joshua L.; Harrison, Scott A.

    2013-01-01

    ActiveGuard™ Mattress Liners have been used to control house dust mites, and they also are commercially available as an integrated pest management tool for use against bed bugs (Cimex lectularius). The aim of our study was to evaluate responses of numerous populations of the bed bug to the permethrin-impregnated fabric, with particular regard to contact toxicity, repellency, and feeding inhibition. Continuous exposure to ActiveGuard fabric resulted in rapid intoxication for three of four populations, with 87 to 100% of moderately pyrethroid-resistant and susceptible bed bugs succumbing by 1 d. In comparison, a highly resistant population reached 22% mortality at 10 d. Video data revealed that bed bugs readily traversed ActiveGuard fabric and spent a considerable amount of time moving about and resting on it during a 12-h period. ActiveGuard fabric was non-repellent to bed bugs from five tested populations. Furthermore, significantly fewer bed bugs successfully fed to repletion through ActiveGuard fabric than through blank fabric for the five populations. With just 30 min of feeding exposure, mortality ranged from 4% to 83%, depending upon the bed bug strain. These laboratory studies indicate that ActiveGuard liners adversely affected bed bugs from diverse populations. PMID:26464388

  11. Behavioral Responses of the Bed Bug to Permethrin-Impregnated ActiveGuard™ Fabric.

    PubMed

    Jones, Susan C; Bryant, Joshua L; Harrison, Scott A

    2013-06-07

    ActiveGuard™ Mattress Liners have been used to control house dust mites, and they also are commercially available as an integrated pest management tool for use against bed bugs (Cimex lectularius). The aim of our study was to evaluate responses of numerous populations of the bed bug to the permethrin-impregnated fabric, with particular regard to contact toxicity, repellency, and feeding inhibition. Continuous exposure to ActiveGuard fabric resulted in rapid intoxication for three of four populations, with 87 to 100% of moderately pyrethroid-resistant and susceptible bed bugs succumbing by 1 d. In comparison, a highly resistant population reached 22% mortality at 10 d. Video data revealed that bed bugs readily traversed ActiveGuard fabric and spent a considerable amount of time moving about and resting on it during a 12-h period. ActiveGuard fabric was non-repellent to bed bugs from five tested populations. Furthermore, significantly fewer bed bugs successfully fed to repletion through ActiveGuard fabric than through blank fabric for the five populations. With just 30 min of feeding exposure, mortality ranged from 4% to 83%, depending upon the bed bug strain. These laboratory studies indicate that ActiveGuard liners adversely affected bed bugs from diverse populations.

  12. On scattering of a material over the Ostwald-de Waele fluid bed

    NASA Astrophysics Data System (ADS)

    Siddiqui, Abuzar A.; Ahmad, Salman; Aqeel, Muhammad

    2016-12-01

    We formulated mathematically, the scattering and sliding of a material (colloid, oil, gasoline etc.) over the Ostwald-de Waele fluid. Ostwald-de Waele fluid model is used to get a boundary value problem (BVP). This BVP comprises coupled nonlinear partial differential equations (PDEs). These PDEs are further transformed into an ordinary differential equation (ODE) under the stream of similarity transform for the high Reynolds number flow assumption. The developed similarity solution is validated. The influence of fluid speed and drag is observed to be intensified in the vicinity of interface.

  13. Recovery of Alkylation Activity in Deactivated USY Catalyst Using Supercritical Fluids: A Comparison of Light Hydrocarbons

    SciTech Connect

    Daniel M. Ginosar; David N. Thompson; Kyle C. Burch

    2004-05-01

    Off-line, in-situ alkylation activity recovery from a completely deactivated solid acid catalyst was examined in a continuous-flow reaction system employing supercritical fluids (SCF). A USY zeolite catalyst was initially deactivated during the liquid phase alkylation of butene with isobutane in a single-pass reactor and then varying amounts of alkylation activity were recovered by passing supercritical fluids over the catalyst bed. A comparison of reactivation fluids on catalyst activity recovery is reported. Fluids examined included helium, propane, n-butane, isobutane, n-pentane, and isopentane. Phases studied included gas, liquid, and supercritical. As much as 82% of the fresh catalyst activity was recovered when employing supercritical isobutane. The ability of the fluid to facilitate a hydride reaction with the adsorbed deactivating high-molecular weight carbocations was indicated as an important property necessary to attain high levels of catalyst activity recovery. Activity recovery utilizing supercritical fluids that enhance reactivation by both reacting with and desorbing fouling compounds appears to be a promising technique to advance solid catalyst alkylation.

  14. Active Polar Two-Fluid Macroscopic Dynamics

    NASA Astrophysics Data System (ADS)

    Pleiner, Harald; Svensek, Daniel; Brand, Helmut R.

    2014-03-01

    We study the dynamics of systems with a polar dynamic preferred direction. Examples include the pattern-forming growth of bacteria (in a solvent, shoals of fish (moving in water currents), flocks of birds and migrating insects (flying in windy air). Because the preferred direction only exists dynamically, but not statically, the macroscopic variable of choice is the macroscopic velocity associated with the motion of the active units. We derive the macroscopic equations for such a system and discuss novel static, reversible and irreversible cross-couplings connected to this second velocity. We find a normal mode structure quite different compared to the static descriptions, as well as linear couplings between (active) flow and e.g. densities and concentrations due to the genuine two-fluid transport derivatives. On the other hand, we get, quite similar to the static case, a direct linear relation between the stress tensor and the structure tensor. This prominent ``active'' term is responsible for many active effects, meaning that our approach can describe those effects as well. In addition, we also deal with explicitly chiral systems, which are important for many active systems. In particular, we find an active flow-induced heat current specific for the dynamic chiral polar order.

  15. Potential fluid mechanic pathways of platelet activation.

    PubMed

    Shadden, Shawn C; Hendabadi, Sahar

    2013-06-01

    Platelet activation is a precursor for blood clotting, which plays leading roles in many vascular complications and causes of death. Platelets can be activated by chemical or mechanical stimuli. Mechanically, platelet activation has been shown to be a function of elevated shear stress and exposure time. These contributions can be combined by considering the cumulative stress or strain on a platelet as it is transported. Here, we develop a framework for computing a hemodynamic-based activation potential that is derived from a Lagrangian integral of strain rate magnitude. We demonstrate that such a measure is generally maximized along, and near to, distinguished material surfaces in the flow. The connections between activation potential and these structures are illustrated through stenotic flow computations. We uncover two distinct structures that may explain observed thrombus formation at the apex and downstream of stenoses. More broadly, these findings suggest fundamental relationships may exist between potential fluid mechanic pathways for mechanical platelet activation and the mechanisms governing their transport.

  16. Overview af MSFC's Applied Fluid Dynamics Analysis Group Activities

    NASA Technical Reports Server (NTRS)

    Garcia, Roberto; Griffin, Lisa; Williams, Robert

    2004-01-01

    This paper presents viewgraphs on NASA Marshall Space Flight Center's Applied Fluid Dynamics Analysis Group Activities. The topics include: 1) Status of programs at MSFC; 2) Fluid Mechanics at MSFC; 3) Relevant Fluid Dynamics Activities at MSFC; and 4) Shuttle Return to Flight.

  17. Computational fluid dynamics modelling of biomass fast pyrolysis in fluidised bed reactors, focusing different kinetic schemes.

    PubMed

    Ranganathan, Panneerselvam; Gu, Sai

    2016-08-01

    The present work concerns with CFD modelling of biomass fast pyrolysis in a fluidised bed reactor. Initially, a study was conducted to understand the hydrodynamics of the fluidised bed reactor by investigating the particle density and size, and gas velocity effect. With the basic understanding of hydrodynamics, the study was further extended to investigate the different kinetic schemes for biomass fast pyrolysis process. The Eulerian-Eulerian approach was used to model the complex multiphase flows in the reactor. The yield of the products from the simulation was compared with the experimental data. A good comparison was obtained between the literature results and CFD simulation. It is also found that CFD prediction with the advanced kinetic scheme is better when compared to other schemes. With the confidence obtained from the CFD models, a parametric study was carried out to study the effect of biomass particle type and size and temperature on the yield of the products.

  18. Production of activated carbon from coconut shell char in a fluidized bed reactor

    SciTech Connect

    Sai, P.M.S.; Ahmed, J.; Krishnaiah, K.

    1997-09-01

    Activated carbon is produced from coconut shell char using steam or carbon dioxide as the reacting gas in a 100 mm diameter fluidized bed reactor. The effect of process parameters such as reaction time, fluidizing velocity, particle size, static bed height, temperature of activation, fluidizing medium, and solid raw material on activation is studied. The product is characterized by determination of iodine number and BET surface area. The product obtained in the fluidized bed reactor is much superior in quality to the activated carbons produced by conventional processes. Based on the experimental observations, the optimum values of process parameters are identified.

  19. New class of turbulence in active fluids

    PubMed Central

    Bratanov, Vasil; Frey, Erwin

    2015-01-01

    Turbulence is a fundamental and ubiquitous phenomenon in nature, occurring from astrophysical to biophysical scales. At the same time, it is widely recognized as one of the key unsolved problems in modern physics, representing a paradigmatic example of nonlinear dynamics far from thermodynamic equilibrium. Whereas in the past, most theoretical work in this area has been devoted to Navier–Stokes flows, there is now a growing awareness of the need to extend the research focus to systems with more general patterns of energy injection and dissipation. These include various types of complex fluids and plasmas, as well as active systems consisting of self-propelled particles, like dense bacterial suspensions. Recently, a continuum model has been proposed for such “living fluids” that is based on the Navier–Stokes equations, but extends them to include some of the most general terms admitted by the symmetry of the problem [Wensink HH, et al. (2012) Proc Natl Acad Sci USA 109:14308–14313]. This introduces a cubic nonlinearity, related to the Toner–Tu theory of flocking, which can interact with the quadratic Navier–Stokes nonlinearity. We show that as a result of the subtle interaction between these two terms, the energy spectra at large spatial scales exhibit power laws that are not universal, but depend on both finite-size effects and physical parameters. Our combined numerical and analytical analysis reveals the origin of this effect and even provides a way to understand it quantitatively. Turbulence in active fluids, characterized by this kind of nonlinear self-organization, defines a new class of turbulent flows. PMID:26598708

  20. Motility of active fluid drops on surfaces

    NASA Astrophysics Data System (ADS)

    Khoromskaia, Diana; Alexander, Gareth P.

    2015-12-01

    Drops of active liquid crystal have recently shown the ability to self-propel, which was associated with topological defects in the orientation of active filaments [Sanchez et al., Nature 491, 431 (2013), 10.1038/nature11591]. Here, we study the onset and different aspects of motility of a three-dimensional drop of active fluid on a planar surface. We analyze theoretically how motility is affected by orientation profiles with defects of various types and locations, by the shape of the drop, and by surface friction at the substrate. In the scope of a thin drop approximation, we derive exact expressions for the flow in the drop that is generated by a given orientation profile. The flow has a natural decomposition into terms that depend entirely on the geometrical properties of the orientation profile, i.e., its bend and splay, and a term coupling the orientation to the shape of the drop. We find that asymmetric splay or bend generates a directed bulk flow and enables the drop to move, with maximal speeds achieved when the splay or bend is induced by a topological defect in the interior of the drop. In motile drops the direction and speed of self-propulsion is controlled by friction at the substrate.

  1. Fluid Transport Driven by Heat-Generating Nuclear Waste in Bedded Salt

    NASA Astrophysics Data System (ADS)

    Jordan, A.; Harp, D. R.; Stauffer, P. H.; Ten Cate, J. A.; Labyed, Y.; Boukhalfa, H.; Lu, Z.; Person, M. A.; Robinson, B. A.

    2013-12-01

    The question of where to safely dispose high-level nuclear waste (HLW) provides ample motivation for scientific research on deep geologic disposal options. The goal of this study is to model the dominant heat and mass transport processes that would be driven by heat generating nuclear waste buried in bedded salt. The interaction between liquid brine flow towards the heat source, establishment of a heat pipe in the mine-run salt backfill, boiling, and vapor condensation leads to changes in porosity, permeability, saturation, thermal conductivity, and rheology of the salt surrounding potential waste canisters. The Finite Element Heat and Mass transfer code (FEHM) was used to simulate these highly coupled thermal, hydrological, and chemical processes. The numerical model has been tested against recent and historical experimental data to develop and improve the salt material model. We used the validated numerical model to make predictions of temperature gradients, porosity changes, and tracer behavior that will be testable in a future 2-year field-scale heater experiment to be carried out in an experimental test bed at the Waste Isolation Pilot Plant (WIPP) site near Carlsbad, NM.

  2. Alumina calcination with the advanced circulating fluid bed technology: A design with increased efficiency combined with operating flexibility

    SciTech Connect

    Schmidt, H.W.; Stockhausen, W.; Silberberg, A.N.

    1996-10-01

    The Circulating Fluid Bed (CFB) technology has now been applied to alumina calcination for a quarter of a century. The combined capacity of the 32 units installed is greater than 10 million metric tons per year. The paper highlights the consistency of the product quality which is based upon the operating experience of the last decade and improvements to the calcination system which also provides lower heat consumption. The principal modifications are incorporated in the preheating and cooling sections of the plant. These design modifications have also reduced capital cost. Overall the plant retains its proven features of high flexibility, unique temperature control, high availability, reliable performance, and low maintenance cost. The design is applicable to single train units up to a capacity of 3,000 MTPD (alumina).

  3. Flexibility of the Fluid-Bed Calciner Process in View of Changing Demands in the Alumina Market

    NASA Astrophysics Data System (ADS)

    Schmidt, Hans Werner; Beisswenger, Hans; Kämpf, Fritz

    1980-02-01

    The two most frequently used types of alumina are finegrained, high-calcined, "floury" alumina and coarse-grained, low-calcined, "sandy" alumina; they result from different calcining conditions. Because of the increasing exchange of alumina on the international market, there is a growing demand for a modern calcining system allowing the production of various qualities. The fluid-bed calciner process is optimally suited to these demands. As grain-size distribution is of great importance for the quality of weakly calcined alumina, extensive investigations have been made to determine the influence of calcination on aluminum hydroxide. It was found that, besides the mechanical strength of the aluminum hydroxide, local velocity rates, solids concentration, and details of design affect the grain size of calcined alumina. Results from pilot and industrial plants are presented and discussed with regard to consequences for layout and operating conditions of calcining plants.

  4. Detection of seminal fluid proteins in the bed bug, Cimex lectularius, using two-dimensional gel electrophoresis and mass spectrometry.

    PubMed

    Reinhardt, K; Wong, C H; Georgiou, A S

    2009-03-01

    The global increase of the human parasite, the common bed bug Cimex lectularius, calls for specific pest control target sites. The bed bug is also a model species for sexual conflict theory which suggests that seminal fluids may be highly diverse. The species has a highly unusual sperm biology and seminal proteins may have unique functions. One-dimensional PAGE gels showed 40-50% band sharing between C. lectularius and another cimicid species, Afrocimex constrictus. However, adult, sexually rested C. lectularius males were found to store 5-7 microg of seminal protein and with only 60 microg of protein we obtained informative 2-D PAGE gels. These showed 79% shared protein spots between 2 laboratory populations, and more than half of the shared protein spots were detected in the mated female. Further analysis using liquid chromatography electrospray ionization tandem mass spectrometry revealed that 26.5% of the proteins had matches among arthropods in databases and 14.5% matched Drosophila proteins. These included ubiquitous proteins but also those more closely associated with reproduction such as moj 29, ubiquitin, the stress-related elongation factor EF-1 alpha, a protein disulfide isomerase and an antioxidant, Peroxiredoxin 6.

  5. Evaluation of extended-release applications for solid dispersion hot-melt fluid bed coatings utilizing hydrophobic coating agents.

    PubMed

    Kennedy, J P; Niebergall, P J

    1998-02-01

    A new hot-melt fluid bed coating method was evaluated for potential extended-release applications. Chlorpheniramine maleate (CPM) USP was chosen as a model drug. The assays for drug release and content uniformity were dictated by the USP Official Monograph for a Chlorpheniramine Maleate Extended-Release Capsule. The fluid bed chamber was charged with CPM-loaded nonpareils and hydrophobic coating agents in the solid state. The method consists of four processing stages: (a) warming, (b) preheating, (c) melting-spreading, and (d) cooling-congealing. Various hydrophobic coating agent candidates were evaluated for extended-release potential by a preliminary screen at a coating agent level of 1.5% (w/w). A beeswax coating agent was identified as the most promising candidate of the preliminary screen. After the level of beeswax was increased to 2.0%, the dissolution profile met all of the specifications of the USP Drug Release Test 1 for a CPM Extended-Release Capsule. The potency and content uniformity remained unchanged by the process. Dual coatings demonstrated a cumulative extension of release superior to the capability of a single coat. The new method is a viable alternative to hot-melt spray-coating methodologies. Organic solvents, spraying equipment, steam jackets, and/or heating tape are eliminated from the process. A reduction of equipment costs, setup time, and cleanup time may be realized. The method has demonstrated extended-release capabilities. No excessive attrition of potency or content uniformity has been noted. Additive, multiple coatings that have a cumulative effect on release retardation are feasible.

  6. Tissue plasminogen activator in the bed nucleus of stria terminalis regulates acoustic startle.

    PubMed

    Matys, T; Pawlak, R; Strickland, S

    2005-01-01

    The bed nucleus of stria terminalis is a basal forebrain region involved in regulation of hormonal and behavioral responses to stress. In this report we demonstrate that bed nucleus of stria terminalis has a high and localized expression of tissue plasminogen activator, a serine protease with neuromodulatory properties and implicated in neuronal plasticity. Tissue plasminogen activator activity in the bed nucleus of stria terminalis is transiently increased in response to acute restraint stress or i.c.v. administration of a major stress mediator, corticotropin-releasing factor. We show that tissue plasminogen activator is important in bed nucleus of stria terminalis function using two criteria: 1, Neuronal activation in this region as measured by c-fos induction is reduced in tissue plasminogen activator-deficient mice; and 2, a bed nucleus of stria terminalis-dependent behavior, potentiation of acoustic startle by corticotropin-releasing factor, is attenuated in tissue plasminogen activator-deficient mice. These studies identify a novel site of tissue plasminogen activator expression in the mouse brain and demonstrate a functional role for this protease in the bed nucleus of stria terminalis.

  7. The development of an integrated multistage fluid bed retorting process. [Kentort II process--50-lb/hr

    SciTech Connect

    Carter, S.; Stehn, J.; Vego, A.; Taulbee, D.

    1992-05-01

    This report summarizes the progress made on the development of an integrated multistage fluidized bed retorting process (KENTORT II) during the period of January 1, 1992 through March 31, 1992. The KENTORT II process includes integral fluidized bed zones for pyrolysis, gasification, and combustion of the oil shale. The purpose of this program is to design and test the KENTORT II process at the 50-lb/hr scale. The design of the 50-lb/hr KENTORT II retort was completed and fabrication is ready to begin. Data from the cold-flow model of the system and operating experience from the 5-lb/hr unit were used as the basis for the design. In another aspect of the program, a study of the cracking and coking kinetics of shale oil vapors was continued. A mathematical model was implemented to characterize the important mass transfer effects of the system. This model will be eventually broadened to become a general fluidized bed coking model. In addition, experiments were performed to examine the effects of surface area, initial carbon content and steam treatment on coking activity. From the data that has been collected to-date, it appears that the coking activity of the tested substrates can be explained in terms of porosity (surface area and pore volume) and the initial carbon content of the solid.

  8. The development of an integrated multistage fluid bed retorting process. Technical report, January 1, 1992--March 31, 1992

    SciTech Connect

    Carter, S.; Stehn, J.; Vego, A.; Taulbee, D.

    1992-05-01

    This report summarizes the progress made on the development of an integrated multistage fluidized bed retorting process (KENTORT II) during the period of January 1, 1992 through March 31, 1992. The KENTORT II process includes integral fluidized bed zones for pyrolysis, gasification, and combustion of the oil shale. The purpose of this program is to design and test the KENTORT II process at the 50-lb/hr scale. The design of the 50-lb/hr KENTORT II retort was completed and fabrication is ready to begin. Data from the cold-flow model of the system and operating experience from the 5-lb/hr unit were used as the basis for the design. In another aspect of the program, a study of the cracking and coking kinetics of shale oil vapors was continued. A mathematical model was implemented to characterize the important mass transfer effects of the system. This model will be eventually broadened to become a general fluidized bed coking model. In addition, experiments were performed to examine the effects of surface area, initial carbon content and steam treatment on coking activity. From the data that has been collected to-date, it appears that the coking activity of the tested substrates can be explained in terms of porosity (surface area and pore volume) and the initial carbon content of the solid.

  9. The development of an integrated multistaged fluid bed retorting process. Technical report, October 1, 1992--December 31, 1992

    SciTech Connect

    Taulbee, D.; Fei, Y.; Carter, S.

    1993-01-01

    The KENTORT II process includes integral fluidized bed zones for pyrolysis, gasification, and combustion of the oil shale. The purpose of this program is to design and test the KENTORT II process at the 50-lb/hr scale. Along with the major activity of assembling the components of the 50-lb/hr retort, work was also completed in other areas this quarter. Basic studies of the cracking and coking kinetics of model compounds in a fixed bed reactor were continued. Additionally, as part of the effort to investigate niche market applications for KENTORT II-derived products, a study of the synthesis of carbon fibers from the heavy fraction of KENTORT II shale oil was initiated.

  10. Overview of MSFC's Applied Fluid Dynamics Analysis Group Activities

    NASA Technical Reports Server (NTRS)

    Garcia, Roberto; Griffin, Lisa; Williams, Robert

    2002-01-01

    This viewgraph report presents an overview of activities and accomplishments of NASA's Marshall Space Flight Center's Applied Fluid Dynamics Analysis Group. Expertise in this group focuses on high-fidelity fluids design and analysis with application to space shuttle propulsion and next generation launch technologies. Topics covered include: computational fluid dynamics research and goals, turbomachinery research and activities, nozzle research and activities, combustion devices, engine systems, MDA development and CFD process improvements.

  11. Genome-Centric Analysis of Microbial Populations Enriched by Hydraulic Fracture Fluid Additives in a Coal Bed Methane Production Well.

    PubMed

    Robbins, Steven J; Evans, Paul N; Parks, Donovan H; Golding, Suzanne D; Tyson, Gene W

    2016-01-01

    Coal bed methane (CBM) is generated primarily through the microbial degradation of coal. Despite a limited understanding of the microorganisms responsible for this process, there is significant interest in developing methods to stimulate additional methane production from CBM wells. Physical techniques including hydraulic fracture stimulation are commonly applied to CBM wells, however the effects of specific additives contained in hydraulic fracture fluids on native CBM microbial communities are poorly understood. Here, metagenomic sequencing was applied to the formation waters of a hydraulically fractured and several non-fractured CBM production wells to determine the effect of this stimulation technique on the in-situ microbial community. The hydraulically fractured well was dominated by two microbial populations belonging to the class Phycisphaerae (within phylum Planctomycetes) and candidate phylum Aminicenantes. Populations from these phyla were absent or present at extremely low abundance in non-fractured CBM wells. Detailed metabolic reconstruction of near-complete genomes from these populations showed that their high relative abundance in the hydraulically fractured CBM well could be explained by the introduction of additional carbon sources, electron acceptors, and biocides contained in the hydraulic fracture fluid.

  12. Genome-Centric Analysis of Microbial Populations Enriched by Hydraulic Fracture Fluid Additives in a Coal Bed Methane Production Well

    PubMed Central

    Robbins, Steven J.; Evans, Paul N.; Parks, Donovan H.; Golding, Suzanne D.; Tyson, Gene W.

    2016-01-01

    Coal bed methane (CBM) is generated primarily through the microbial degradation of coal. Despite a limited understanding of the microorganisms responsible for this process, there is significant interest in developing methods to stimulate additional methane production from CBM wells. Physical techniques including hydraulic fracture stimulation are commonly applied to CBM wells, however the effects of specific additives contained in hydraulic fracture fluids on native CBM microbial communities are poorly understood. Here, metagenomic sequencing was applied to the formation waters of a hydraulically fractured and several non-fractured CBM production wells to determine the effect of this stimulation technique on the in-situ microbial community. The hydraulically fractured well was dominated by two microbial populations belonging to the class Phycisphaerae (within phylum Planctomycetes) and candidate phylum Aminicenantes. Populations from these phyla were absent or present at extremely low abundance in non-fractured CBM wells. Detailed metabolic reconstruction of near-complete genomes from these populations showed that their high relative abundance in the hydraulically fractured CBM well could be explained by the introduction of additional carbon sources, electron acceptors, and biocides contained in the hydraulic fracture fluid. PMID:27375557

  13. The development of an integrated multistaged fluid bed retorting process. Annual report, October 1, 1992--September 30, 1993

    SciTech Connect

    Carter, S.; Taulbee, D.; Vego, A.; Stehn, J.; Fei, Y.; Robl, T.; Derbyshire, F.

    1993-11-01

    This report summarizes the progress made on the development of an integrated multistage fluidized bed retorting process (KENTORT II) during the period of October 1, 1992 through September 30, 1993 under Cooperative Agreement No. DE-FC21-90MC27286 with the Morgantown Energy Technology Center, US Department of Energy. The KENTORT II process includes integral fluidized bed zones for pyrolysis, gasification, and combustion of the oil shale. The purpose of this program is to design and test the KENTORT II process at the 50-lb/hr scale. The PDU was assembled, instrumented and tested during this fiscal year. Along with the major activity of commissioning the 50-lb/hr retort, work was also completed in other areas. Basic studies of the cracking and coking kinetics of model compounds in a fixed bed reactor were continued. Additionally, as part of the effort to investigate niche market applications for KENTORT II-derived products, a study of the synthesis of carbon fibers from the heavy fraction of KENTORT II shale oil was initiated.

  14. Plasma lactic dehydrogenase activities in men during bed rest with exercise training

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Juhos, L. T.; Young, H. L.

    1985-01-01

    Peak oxygen uptake and the activity of lactic dehydrogenase (LDH-T) and its five isoenzymes were measured by spectrophotometer in seven men before, during, and after bed rest and exercise training. Exercise training consisted of isometric leg exercises of 250 kcal/hr for a period of one hour per day. It is found that LDH-T was reduced by 0.05 percent in all three regimens by day 10 of bed rest, and that the decrease occurred at different rates. The earliest reduction in LDH-T activity in the no-exercise regimen was associated with a decrease in peak oxygen uptake of 12.3 percent. It is concluded that isometric (aerobic) muscular strength training appear to maintain skeletal muscle integrity better during bed rest than isotonic exercise training. Reduced hydrostatic pressure during bed rest, however, ultimately counteracts the effects of both moderate isometric and isotonic exercise training, and may result in decreased LDH-T activity.

  15. Origin of fluid inclusion water in bedded salt deposits, Palo Duro Basin, Texas

    SciTech Connect

    Knauth, L.P.; Beeunas, M.A.

    1985-07-01

    Salt horizons in the Palo Duro Basin being considered for repository sites contain fluid inclusions which may represent connate water retained in the salt from the time of original salt deposition and/or external waters which have somehow penetrated the salt. The exact origin of this water is important to the question of whether or not internal portions of the salt deposit have been, and are likely to be, isolated from the hydrosphere for long periods of time. The /sup 18/O//sup 16/O and D/H ratios measured for water extracted from solid salt samples show the inclusions to be dissimilar in isotopic composition to meteoric waters and to formation waters above and below the salt. The fluid inclusions cannot be purely external waters which have migrated into the salt. The isotope data are readily explained in terms of mixed meteoric-marine connate evaporite waters which date back to the time of deposition and early diagenesis of the salt (>250 million years). Any later penetration of the salt by meteoric waters has been insufficient to flush out the connate brines.

  16. Overview of MSFC's Applied Fluid Dynamics Analysis Group Activities

    NASA Technical Reports Server (NTRS)

    Garcia, Roberto; Griffin, Lisa; Williams, Robert

    2003-01-01

    TD64, the Applied Fluid Dynamics Analysis Group, is one of several groups with high-fidelity fluids design and analysis expertise in the Space Transportation Directorate at Marshall Space Flight Center (MSFC). TD64 assists personnel working on other programs. The group participates in projects in the following areas: turbomachinery activities, nozzle activities, combustion devices, and the Columbia accident investigation.

  17. Stable isotope composition of fluid inclusions preserved in halite derived from Wieliczka and Bochnia Salt Beds (Southern Poland)

    NASA Astrophysics Data System (ADS)

    Dulinski, Marek; Rozanski, Kazimierz; Bukowski, Krzysztof

    2010-05-01

    Halite deposits located in the southern Poland, near Krakow, are famous mostly due to the medieval salt mine located in Wieliczka. Contrary to most salt deposits in Europe forming large domes, the halite deposits near Krakow form distinct beds, extending from west to east on the area of ca. 10 km2, with several types of salt identified. The deposits were formed in shallow environment, ca. 15 mln years ago and represent initial stages of Miocene sea water evaporation. Stable isotope composition of fluid inclusions trapped in the halite crystals originating from Wieliczka and Bochnia salt mines was investigated. Three distinct groups of samples were analysed: (i) samples derived from so-called 'green salt' beds forming extensive horizontal structures, (ii) samples derived from so-called zuber-type salt, and (iii) large monocrystals of halite collected in two crystal caves existing in the mine. The samples belonging to the first and second group were heated under vacuum to extract the fluid inclusions, according to the procedure used previously to extract inclusions from speleothem samples. The macro-inclusions present in some monocrystals of halite collected in crystal caves were removed for analysis without any thermal treatment. The concentration of bivalent cations (Ca2+, Mg2+) was measured in the bulk material (green salt). K+, Mg2+ and SO4-2 content was measured in the fluid inclusions derived from macro-crystals. The stable isotope data points form two clusters in the δ2H-δ18O space, representing crystal caves and green- and zuber-type salts, respectively. The cluster representing green- and zuber-type salt deposit is shifted to the right-hand side of the Local Meteoric Water Line (LMWL), towards more positive δ2H and δ18O values, pointing to evaporative conditions during formation of these deposits. Although the evaporation trajectories for the sea water in the δ2H - δ18O space suggest that fluid inclusions might represent remnants of the original

  18. Breakthrough of toluene vapours in granular activated carbon filled packed bed reactor.

    PubMed

    Mohan, N; Kannan, G K; Upendra, S; Subha, R; Kumar, N S

    2009-09-15

    The objective of this research was to determine the toluene removal efficiency and breakthrough time using commercially available coconut shell-based granular activated carbon in packed bed reactor. To study the effect of toluene removal and break point time of the granular activated carbon (GAC), the parameters studied were bed lengths (2, 3, and 4 cm), concentrations (5, 10, and 15 mg l(-1)) and flow rates (20, 40, and 60 ml/min). The maximum percentage removal of 90% was achieved and the maximum carbon capacity for 5 mg l(-1) of toluene, 60 ml/min flow rate and 3 cm bed length shows 607.14 mg/g. The results of dynamic adsorption in a packed bed were consistent with those of equilibrium adsorption by gravimetric method. The breakthrough time and quantity shows that GAC with appropriate surface area can be utilized for air cleaning filters. The result shows that the physisorption plays main role in toluene removal.

  19. Systematic reviews of bed rest and advice to stay active for acute low back pain.

    PubMed Central

    Waddell, G; Feder, G; Lewis, M

    1997-01-01

    BACKGROUND: In the United Kingdom (UK), 9% of adults consult their doctor annually with back pain. The treatment recommendations are based on orthopaedic teaching, but the current management is causing increasing dissatisfaction. Many general practitioners (GPs) are confused about what constitutes effective advice. AIM: To review all randomized controlled trials of bed rest and of medical advice to stay active for acute back pain. METHOD: A systematic review based on a search of MEDLINE and EMBASE from 1966 to April 1996 with complete citation tracking for randomized controlled trials of bed rest or medical advice to stay active and continue ordinary daily activities. The inclusion criteria were: primary care setting, patients with low back pain of up to 3 months duration, and patient-centred outcomes (rate of recovery from the acute attack, relief of pain, restoration of function, satisfaction with treatment, days off work and return to work, development of chronic pain and disability, recurrent attacks, and further health care use). RESULTS: Ten trials of bed rest and eight trials of advice to stay active were identified. Consistent findings showed that bed rest is not an effective treatment for acute low back pain but may delay recovery. Advice to stay active and to continue ordinary activities results in a faster return to work, less chronic disability, and fewer recurrent problems. CONCLUSION: A simple but fundamental change from the traditional prescription of bed rest to positive advice about staying active could improve clinical outcomes and reduce the personal and social impact of back pain. PMID:9474831

  20. Modeling of the Fluid Flow and Heat Transfer an a Pebble Bed Modular Reactor Core With a Computational Fluid Dynamics Code

    SciTech Connect

    Taylor, J. Bryce; Yavuzkurt, Savas; Baratta, Anthony J.

    2002-07-01

    The Pebble Bed Modular Reactor (PBMR), a promising Generation IV nuclear reactor design, raises many novel technological issues for which new experience and techniques must be developed. This brief study explores a few of these issues, utilizes a computational fluid dynamics code to model some simple phenomena, and points out deficiencies in current knowledge that should be addressed by future research and experimentation. A highly simplified representation of the PBMR core is analyzed with FLUENT, a commercial computational fluid dynamics code. The applied models examine laminar and turbulent flow in the vicinity of a single spherical fuel pebble near the center of the core, accounting for the effects of the immediately adjacent fuel pebbles. Several important fluid flow and heat transfer parameters are examined, including heat transfer coefficient, Nusselt number, and pressure drop, as well as the temperature, pressure, and velocity profiles near the fuel pebble. The results of these 'unit cell' calculations are also compared to empirical correlations available in the literature. As FLUENT is especially sensitive to geometry during the generation of a computational mesh, the sensitivity of code results to pebble spacing is also examined. The results of this study show that while a PBMR presents a novel and complex geometry, a code such as FLUENT is suitable for calculation of both local and global flow characteristics, and can be a valuable tool for the thermal-hydraulic study of this new reactor design. FLUENT results for pressure drop deviate from the Darcy correlation by several orders of magnitude in all cases. When determining the heat transfer coefficient, FLUENT is again much lower than Robinson's correlation. Results for Nusselt number show better agreement, with FLUENT predicting results that are 10 or 20 times as large as those from the Robinson and Lancashire correlations. These differences may arise because the empirical correlations concern mainly

  1. Slope effects on the fluid dynamics of a fire spreading across a fuel bed: PIV measurements and OH* chemiluminescence imaging

    NASA Astrophysics Data System (ADS)

    Morandini, F.; Silvani, X.; Honoré, D.; Boutin, G.; Susset, A.; Vernet, R.

    2014-08-01

    Slope is among the most influencing factor affecting the spread of wildfires. A contribution to the understanding of the fluid dynamics of a fire spreading in these terrain conditions is provided in the present paper. Coupled optical diagnostics are used to study the slope effects on the flow induced by a fire at laboratory scale. Optical diagnostics consist of particle image velocimetry, for investigating the 2D (vertical) velocity field of the reacting flow and chemiluminescence imaging, for visualizing the region of spontaneous emission of OH radical occurring during gaseous combustion processes. The coupling of these two techniques allows locating accurately the contour of the reaction zone within the computed velocity field. The series of experiments are performed across a bed of vegetative fuel, under both no-slope and 30° upslope conditions. The increase in the rate of fire spread with increasing slope is attributed to a significant change in fluid dynamics surrounding the flame. For horizontal fire spread, flame fronts exhibit quasi-vertical plume resulting in the buoyancy forces generated by the fire. These buoyancy effects induce an influx of ambient fresh air which is entrained laterally into the fire, equitably from both sides. For upward flame spread, the induced flow is strongly influenced by air entrainment on the burnt side of the fire and fire plume is tilted toward unburned vegetation. A particular attention is paid to the induced air flow ahead of the spreading flame. With increasing the slope angle beyond a threshold, highly dangerous conditions arise because this configuration induces wind blows away from the fire rather than toward it, suggesting the presence of convective heat transfers ahead of the fire front.

  2. Questing activity in bed bug populations: male and female responses to host signals.

    PubMed

    Aak, Anders; Rukke, Bjørn A; Soleng, Arnulf; Rosnes, Marte K

    2014-09-01

    A large-arena bioassay is used to examine sex differences in spatiotemporal patterns of bed bug Cimex lectularius L. behavioural responses to either a human host or CO2 gas. After release in the centre of the arena, 90% of newly-fed bed bugs move to hiding places in the corners within 24 h. They require 3 days to settle down completely in the arena, with generally low activity levels and the absence of responses to human stimuli for 5 days. After 8-9 days, persistent responses can be recorded. Sex differences are observed, in which females are more active during establishment, respond faster after feeding, expose themselves more than males during the daytime, and respond more strongly to the host signal. The number of bed bugs that rest in harbourages is found to vary significantly according to light setting and sex. Both sexes stay inside harbourages more in daylight compared with night, and males hide more than females during the daytime but not during the night. The spatial distribution of the bed bugs is also found to change with the presence of CO2, and peak aggregation around the odour source is observed after 24 min. Both male and female bed bugs move from hiding places or the border of the arena toward the centre where CO2 is released. Peak responses are always highest during the night. Bed bug behaviour and behaviour-regulating features are discussed in the context of control methods.

  3. Questing activity in bed bug populations: male and female responses to host signals

    PubMed Central

    Aak, Anders; Rukke, Bjørn A; Soleng, Arnulf; Rosnes, Marte K

    2014-01-01

    A large-arena bioassay is used to examine sex differences in spatiotemporal patterns of bed bug Cimex lectularius L. behavioural responses to either a human host or CO2 gas. After release in the centre of the arena, 90% of newly-fed bed bugs move to hiding places in the corners within 24 h. They require 3 days to settle down completely in the arena, with generally low activity levels and the absence of responses to human stimuli for 5 days. After 8–9 days, persistent responses can be recorded. Sex differences are observed, in which females are more active during establishment, respond faster after feeding, expose themselves more than males during the daytime, and respond more strongly to the host signal. The number of bed bugs that rest in harbourages is found to vary significantly according to light setting and sex. Both sexes stay inside harbourages more in daylight compared with night, and males hide more than females during the daytime but not during the night. The spatial distribution of the bed bugs is also found to change with the presence of CO2, and peak aggregation around the odour source is observed after 24 min. Both male and female bed bugs move from hiding places or the border of the arena toward the centre where CO2 is released. Peak responses are always highest during the night. Bed bug behaviour and behaviour-regulating features are discussed in the context of control methods. PMID:26166936

  4. Circadian rhythm of spontaneous locomotor activity in the bed bug, Cimex lectularius L.

    PubMed

    Romero, Alvaro; Potter, Michael F; Haynes, Kenneth F

    2010-11-01

    Bed bugs must avoid detection when finding hosts and returning to hidden harborages. Their stealthy habits include foraging when hosts are asleep. Characteristics of spontaneous locomotor activity rhythm of bed bugs with different feeding histories were studied. In the absence of host stimuli, adults and nymphs were much more active in the dark than in the light. The onset of activity in the scotophase commenced soon after lights-off. The free-running period (tau) for all stages was longer in continuous darkness (DD) than in continuous light (LL). The lengthening of tau in DD is an exception for the circadian rule that predicts the opposite in nocturnal animals. Activity in all stages was entrained to reverse L:D regimes within four cycles. Short-term starved adults moved more frequently than recently fed adults. While bed bugs can survive for a year or more without a blood meal, we observed a reduction in activity in insects held for five weeks without food. We suggest that bed bugs make a transition to host-stimulus dependent searching when host presence is not predictable. Such a strategy would enable bed bugs to maximize reproduction when resources are abundant and save energy when resources are scarce.

  5. Properties of Spent Active Coke Particles Analysed via Comminution in Spouted Bed

    PubMed Central

    Buczek, Bronislaw

    2013-01-01

    Samples of active coke, fresh and spent after cleaning flue gases from communal waste incinerators, were investigated. The outer layers of both coke particles were separately removed by comminution in a spouted bed. The samples of both active cokes were analysed by means of densities, mercury porosimetry, and adsorption technique. Remaining cores were examined to determine the degree of consumption of coke by the sorption of hazardous emissions (SO2, HCl, and heavy metals) through its bed. Differences in contamination levels within the porous structure of the particles were estimated. The study demonstrated the effectiveness of commercial active coke in the cleaning of flue gases. PMID:24459454

  6. Online monitoring of particle mass flow rate in bottom spray fluid bed coating--development and application.

    PubMed

    Wang, Li Kun; Heng, Paul Wan Sia; Liew, Celine Valeria

    2010-08-16

    The primary purpose of this study is to develop a visiometric process analyzer for online monitoring of particle mass flow rate in the bottom spray fluid bed coating process. The secondary purpose is to investigate the influences of partition gap and air accelerator insert size on particle mass flow rate using the developed visiometric process analyzer. Particle movement in the region between the product chamber and partition column was captured using a high speed camera. Mean particle velocity and number of particles in the images were determined by particle image velocimetry and morphological image processing method respectively. Mass flow rate was calculated using particle velocity, number of particles in the images, particle density and size information. Particle velocity and number findings were validated using image tracking and manual particle counting techniques respectively. Validation experiments showed that the proposed method was accurate. Partition gap was found to influence particle mass flow rate by limiting the rate of solids flux into the partition column; the air accelerator insert was found to influence particle mass flow rate by a Venturi effect. Partition gap and air accelerator insert diameter needed to be adjusted accordingly in relation to the other variability sources and diameter of coating cores respectively. The potential, challenges and possible solutions of the proposed visiometric process analyzer were further discussed.

  7. Development of a fluid bed granulation process control strategy based on real-time process and product measurements.

    PubMed

    Burggraeve, Anneleen; Silva, Ana F T; Van den Kerkhof, Tom; Hellings, Mario; Vervaet, Chris; Remon, Jean Paul; Vander Heyden, Yvan; De Beer, Thomas

    2012-10-15

    This article describes the results of three case studies conducted consecutively, in order to develop a process control strategy for a top-spray fluid bed granulation process. The use of several real-time particle size (i.e., spatial filter velocimetry and focused beam reflectance measurement) and moisture (i.e., near infrared (NIR) and Lighthouse near infrared spectroscopy) analyzers was examined. A feed-forward process control method was developed, where in-line collected granulation information during the process spraying phase was used to determine the optimum drying temperature of the consecutive drying phase. Via real-time monitoring of process (i.e., spraying temperature and spray rate) and product (i.e., granule size distribution and moisture) parameters during the spraying period, the batch bulk density was predicted at the end of the spraying cycle, using a PLS model. When this predicted bulk density was not meeting the desired value, the developed control method allowed the calculation of an adjusted drying temperature leading to the desired batch bulk density at the end of the granulation process. Besides the development of the feed-forward control strategy, a quantitative PLS model for in-line moisture content prediction of the granulated end product was built using the NIR data.

  8. Hydrodynamics and energy consumption studies in a three-phase liquid circulating three-phase fluid bed contactor

    SciTech Connect

    Rusumdar, Ahmad J; Abuthalib, A.; Mohan, Vaka Murali; Srinivasa Kumar, C.; Sujatha, V.; Rajendra Prasad, P.

    2009-07-15

    The hydrodynamics and energy consumption have been studied in a cold flow, bubbling and turbulent, pressurized gas-liquid-solid three-phase fluidized bed (0.15 m ID x 1 m height) with concurrent gas-liquid up flow is proposed with the intention of increasing the gas hold up. The hydrodynamic behaviour is described and characterised by some specific gas and liquid velocities. Particles are easily fluidized and can be uniformly distributed over the whole height of the column. The effect of parameters like liquid flow rate, gas flow rate, particle loading, particle size, and solid density on gas hold up and effect of gas flow rate, solid density and particle size on solid hold up, energy consumption and minimum fluidization velocity has been studied. At the elevated pressures a superior method for better prediction of minimum fluidization velocity and terminal settling velocities has been adopted. The results have been interpreted with Bernoulli's theorem and Richardson-Zaki equation. Based on the assumption of the gas and liquid as a pretend fluid, a simplification has been made to predict the particle terminal settling velocities. The Richardson-Zaki parameter n' was compared with Renzo's results. A correlation has been proposed with the experimental results for the three-phase fluidization. (author)

  9. The development of an integrated multistaged fluid-bed retorting process. Final report, September 1990--August 1994

    SciTech Connect

    Carter, S.D.; Taulbee, D.N.; Stehn, J.L.; Vego, A.; Robl, T.L.

    1995-02-01

    This summarizes the development of the KENTORT II retorting process, which includes integral fluidized bed zones for pyrolysis, gasification, and combustion of oil shale. Purpose was to design and test the process at the 50-lb/hr scale. The program included bench- scale studies of coking and cracking reactions of shale oil vapors over processed shale particles to address issues of scaleup associated with solid-recycle retorting. The bench-scale studies showed that higher amounts of carbon coverage reduce the rate of subsequent carbon deposition by shale oil vapors onto processed shale particles; however carbon-covered materials were also active in terms of cracking and coking. Main focus was the 50-lb/hr KENTORT II PDU. Cold-flow modeling and shakedown were done before the PDU was made ready for operation. Seven mass-balanced, steady-state runs were completed within the window of design operating conditions. Goals were achieved: shale feedrate, run duration (10 hr), shale recirculation rates (4:1 to pyrolyzer and 10:1 to combustor), bed temperatures (pyrolyzer 530{degree}C, gasifier 750{degree}C, combustor 830{degree}C), and general operating stability. Highest oil yields (up to 109% of Fischer assay) were achieved for runs lasting {ge} 10 hours. High C content of the solids used for heat transfer to the pyrolysis zone contributed to the enhanced oil yield achieved.

  10. [Oral fluid bacteriocidal activity in complex diagnostics of oral disbiosis].

    PubMed

    Rabinovich, O F; Abramova, E S

    2012-01-01

    The possibility of examination of oral fluid bacteriocidal activity in complex diagnostics of oral mucosa disbiosis was evaluated. Thirty-seven patients were included in complex clinical and laboratory studies. The patients were divided in two groups: main group (30 patients exhibiting various grades of oral mucosa disbiosis) and control group (7 patients with no signs of oral disbiosis). The oral fluid bacteriocidal activity was examined by means of laser flow cytometry. Study results proved oral fluid bacteriocidal activity increase to correlate with the grade of oral mucosa disbiosis thus confirming the usefulness of the method in complex diagnostics of oral disbiosis.

  11. FLUIDIZED BED STEAM REFORMING FOR TREATMENT AND IMMOBILIZATION OF LOW-ACTIVITY WASTE

    SciTech Connect

    HEWITT WM

    2011-04-08

    This report is one of four reports written to provide background information regarding immobilization technologies remaining under consideration for supplemental immobilization of Hanford's low-activity waste. This paper provides the reader a general understanding of fluidized bed steam reforming and its possible application to treat and immobilize Hanford low-activity waste.

  12. Bed rest suppresses bioassayable growth hormone release in response to muscle activity

    NASA Technical Reports Server (NTRS)

    McCall, G. E.; Goulet, C.; Grindeland, R. E.; Hodgson, J. A.; Bigbee, A. J.; Edgerton, V. R.

    1997-01-01

    Hormonal responses to muscle activity were studied in eight men before (-13 or -12 and -8 or -7 days), during (2 or 3, 8 or 9, and 13 or 14 days) and after (+2 or +3 and +10 or +11 days) 17 days of bed rest. Muscle activity consisted of a series of unilateral isometric plantar flexions, including 4 maximal voluntary contractions (MVCs), 48 contractions at 30% MVC, and 12 contractions at 80% MVC, all performed at a 4:1-s work-to-rest ratio. Blood was collected before and immediately after muscle activity to measure plasma growth hormone by radioimmunoassay (IGH) and by bioassay (BGH) of tibia epiphyseal cartilage growth in hypophysectomized rats. Plasma IGH was unchanged by muscle activity before, during, or after bed rest. Before bed rest, muscle activity increased (P < 0.05) BGH by 66% at -13 or -12 days (2,146 +/- 192 to 3,565 +/- 197 microg/l) and by 92% at -8 or -7 days (2,162 +/- 159 to 4,161 +/- 204 microg/l). After 2 or 3 days of bed rest, there was no response of BGH to the muscle activity, a pattern that persisted through 8 or 9 days of bed rest. However, after 13 or 14 days of bed rest, plasma concentration of BGH was significantly lower after than before muscle activity (2,594 +/- 211 to 2,085 +/- 109 microg/l). After completion of bed rest, muscle activity increased BGH by 31% at 2 or 3 days (1,807 +/- 117 to 2,379 +/- 473 microg/l; P < 0.05), and by 10 or 11 days the BGH response was similar to that before bed rest (1,881 +/- 75 to 4,160 +/- 315 microg/l; P < 0.05). These data demonstrate that the ambulatory state of an individual can have a major impact on the release of BGH, but not IGH, in response to a single bout of muscle activity.

  13. Two stage fluid bed-plasma gasification process for solid waste valorisation: technical review and preliminary thermodynamic modelling of sulphur emissions.

    PubMed

    Morrin, Shane; Lettieri, Paola; Chapman, Chris; Mazzei, Luca

    2012-04-01

    Gasification of solid waste for energy has significant potential given an abundant feed supply and strong policy drivers. Nonetheless, significant ambiguities in the knowledge base are apparent. Consequently this study investigates sulphur mechanisms within a novel two stage fluid bed-plasma gasification process. This paper includes a detailed review of gasification and plasma fundamentals in relation to the specific process, along with insight on MSW based feedstock properties and sulphur pollutant therein. As a first step to understanding sulphur partitioning and speciation within the process, thermodynamic modelling of the fluid bed stage has been performed. Preliminary findings, supported by plant experience, indicate the prominence of solid phase sulphur species (as opposed to H(2)S) - Na and K based species in particular. Work is underway to further investigate and validate this.

  14. Active mixing of complex fluids at the microscale

    SciTech Connect

    Ober, Thomas J.; Foresti, Daniele; Lewis, Jennifer A.

    2015-09-22

    Mixing of complex fluids at low Reynolds number is fundamental for a broad range of applications, including materials assembly, microfluidics, and biomedical devices. Of these materials, yield stress fluids (and gels) pose the most significant challenges, especially when they must be mixed in low volumes over short timescales. New scaling relationships between mixer dimensions and operating conditions are derived and experimentally verified to create a framework for designing active microfluidic mixers that can efficiently homogenize a wide range of complex fluids. As a result, active mixing printheads are then designed and implemented for multimaterial 3D printing of viscoelastic inks with programmable control of local composition.

  15. Active mixing of complex fluids at the microscale

    DOE PAGES

    Ober, Thomas J.; Foresti, Daniele; Lewis, Jennifer A.

    2015-09-22

    Mixing of complex fluids at low Reynolds number is fundamental for a broad range of applications, including materials assembly, microfluidics, and biomedical devices. Of these materials, yield stress fluids (and gels) pose the most significant challenges, especially when they must be mixed in low volumes over short timescales. New scaling relationships between mixer dimensions and operating conditions are derived and experimentally verified to create a framework for designing active microfluidic mixers that can efficiently homogenize a wide range of complex fluids. As a result, active mixing printheads are then designed and implemented for multimaterial 3D printing of viscoelastic inks withmore » programmable control of local composition.« less

  16. Active mixing of complex fluids at the microscale

    PubMed Central

    Ober, Thomas J.; Foresti, Daniele; Lewis, Jennifer A.

    2015-01-01

    Mixing of complex fluids at low Reynolds number is fundamental for a broad range of applications, including materials assembly, microfluidics, and biomedical devices. Of these materials, yield stress fluids (and gels) pose the most significant challenges, especially when they must be mixed in low volumes over short timescales. New scaling relationships between mixer dimensions and operating conditions are derived and experimentally verified to create a framework for designing active microfluidic mixers that can efficiently homogenize a wide range of complex fluids. Active mixing printheads are then designed and implemented for multimaterial 3D printing of viscoelastic inks with programmable control of local composition. PMID:26396254

  17. Increased digitalis-like activity in human cerebrospinal fluid after expansion of the extracellular fluid volume

    SciTech Connect

    Halperin, J.A.; Martin, A.M.; Malave, S.

    1985-08-12

    The present study was designed to determine whether acute expansion of the extracellular fluid volume influenced the digitalis-like activity of human cerebrospinal fluid (CSF), previously described. Human CSF samples, drawn before and 30 minutes after the intravenous infusion of 1 liter of either saline or glucose solutions, were assayed for digitalis-like activity by inhibition of either the /sup 86/Rb/sup +/ uptake into human erythrocytes or by the activity of a purified Na/sup +/-K/sup +/ ATPase. The CSF inhibitory activity on both systems significantly increased after the infusion of sodium solutions but did not change after the infusion of glucose. These results indicate that the digitalis-like factor of human CSF might be involved in the regulation of the extracellular fluid volume and electrolyte content and thereby in some of the physiological responses to sodium loading. 31 references, 2 figures, 1 table.

  18. Adsorption of ciprofloxacin and norfloxacin from aqueous solution onto granular activated carbon in fixed bed column.

    PubMed

    Darweesh, Teeba M; Ahmed, Muthanna J

    2017-04-01

    Carbonization of Phoenix dactylifera L stones followed by microwave K2CO3 activation was adopted for preparation of granular activated carbon (KAC). High yield and favorable pore characteristics in terms of surface area and pore volume were reported for KAC as follows: 44%, 852m(2)/g, and 0.671cm(3)/g, respectively. The application of KAC as adsorbent for attraction of ciprofloxacin (CIP) and norfloxacin (NOR) was investigated using fixed bed systems. The effect of flow rate (0.5-1.5ml/min), bed height (15-25cm), and initial drug concentration (75-225mg/l) on the behavior of breakthrough curves was explained. The fixed bed analysis showed the better correlation of breakthrough data by both Thomas and Yoon-Nelson models. Inlet drug concentration was of greatest effect on breakthrough data compared to other fixed bed variables. Experimental and calculated breakthrough data were obtained for CIP and NOR adsorption on KAC, thus being important for design of fixed bed column.

  19. Instabilities, motion and deformation of active fluid droplets

    NASA Astrophysics Data System (ADS)

    Whitfield, Carl A.; Hawkins, Rhoda J.

    2016-12-01

    We consider two minimal models of active fluid droplets that exhibit complex dynamics including steady motion, deformation, rotation and oscillating motion. First we consider a droplet with a concentration of active contractile matter adsorbed to its boundary. We analytically predict activity driven instabilities in the concentration profile, and compare them to the dynamics we find from simulations. Secondly, we consider a droplet of active polar fluid of constant concentration. In this system we predict, motion and deformation of the droplets in certain activity ranges due to instabilities in the polarisation field. Both these systems show spontaneous transitions to motility and deformation which resemble dynamics of the cell cytoskeleton in animal cells.

  20. Opsonic activity of blister fluid from burn patients.

    PubMed Central

    Deitch, E A

    1983-01-01

    The combination of skin loss and immune depression after thermal injury predisposes burn patients to an increased risk of infection. Since the commonest site of infection in the burn patient is the burn wound itself, we elected to study the opsonic activity of locally produced blister fluid, from 18 thermally injured patients, for the two most common organisms colonizing the burn wound (Pseudomonas aeruginosa and Staphylococcus aureus). Blister fluid was as good an opsonin source for staphylococcus as normal serum. In contrast, the blister fluid did not support either the phagocytosis of the intracellular killing of P. aeruginosa. The poor opsonic activity of blister fluid for P. aeruginosa did not appear to be due to the presence of an inhibitory factor(s) since the addition of normal serum restored the opsonic activity of the blister fluid to normal. The concentrations of immunoglobulins and the complement components C3 and C4 in the blister fluid samples were less than half the level of those in normal serum. The opsonic activity of the blister fluid could not be restored to normal by the addition of either immunoglobulin or heat-inactivated serum (56 degrees C for 30 min). Thus, the opsonic factor(s) missing from the blister fluid was heat labile and thus probably represents complement components. That blister fluid had impaired opsonic activity for P. aeruginosa but not for S. aureus indicated that a local humoral defect may be responsible, at least in part, for the high incidence of gram-negative organisms, especially pseudomonads, colonizing the burn wound after thermal injury. PMID:6411619

  1. Influence of the gap size and dielectric constant of the packing on the plasma discharge in a packed bed dielectric barrier discharge reactor: a fluid modeling study

    NASA Astrophysics Data System (ADS)

    van Laer, Koen; Bogaerts, Annemie

    2016-09-01

    Packed bed dielectric barrier discharge (DBD) reactors have proven to be very useful sources of non-thermal plasma for a wide range of applications, of which the environmental applications have received most attention in recent years. Compared to an empty DBD reactor, a packing was introduced to either enhance the energy efficiency of the process, or, if the packing is catalytically active, steer the process towards a preferred end product. A wide range of geometries, bead sizes and bead materials have been tested experimentally in the past. However, since experimental diagnostics become more difficult with a packing present, a computational study is proposed to gain more insight. Using COMSOL's built in plasma module, a 2D axisymmetric fluid model is developed to study the influence of the gap size and the dielectric constant (ɛ) of the packing. Helium is used as discharge gas, at atmospheric pressure and room temperature. By decreasing the gas gap, the electric field strength is enhanced, resulting in a higher number of current peaks per half cycle of applied rf potential. Increasing ɛ also enhances the electric field strength. However, after a certain ɛ, its influence saturates. The electric field strength will no longer increase, leaving the discharge behavior unchanged.

  2. Active microrheology of fluids inside developing zebrafish

    NASA Astrophysics Data System (ADS)

    Taormina, Mike; Parthasarathy, Raghuveer

    2014-03-01

    Biological fluids are a source of diverse and interesting behavior for the soft matter physicist. Since their mechanical properties must be tuned to fulfill functional roles important to the development and health of living things, they often display complex behavior on length and time scales spanning many orders of magnitude. For microbes colonizing an animal host, for example, the mechanical properties of the host environment are of great importance, affecting mobility and hence the ability to establish a stable population. Indeed, some species possess the ability to affect the fluidity of their environment, both directly by chemically modifying it, and indirectly by influencing the host cells' secretion of mucus. Driving magnetically doped micron-scale probes which have been orally micro-gavaged into the intestinal bulb of a larval zebrafish allows the rheology of the mucosal layer within the fish to be measured over three decades of frequency, complementing ecological data on microbial colonization with physical information about the gut environment. Here, we describe the technique, provide the first measurement of mucosal viscosity in a developing animal, and explore the technique's applicability to other small-volume or spatially inhomogeneous fluid samples.

  3. Surface activity of Janus particles adsorbed at fluid-fluid interfaces: Theoretical and experimental aspects.

    PubMed

    Fernandez-Rodriguez, Miguel Angel; Rodriguez-Valverde, Miguel Angel; Cabrerizo-Vilchez, Miguel Angel; Hidalgo-Alvarez, Roque

    2016-07-01

    Since de Gennes coined in 1992 the term Janus particle (JP), there has been a continued effort to develop this field. The purpose of this review is to present the most relevant theoretical and experimental results obtained so far on the surface activity of amphiphilic JPs at fluid interfaces. The surface activity of JPs at fluid-fluid interfaces can be experimentally determined using two different methods: the classical Langmuir balance or the pendant drop tensiometry. The second method requires much less amount of sample than the first one, but it has also some experimental limitations. In all cases collected here the JPs exhibited a higher surface or interfacial activity than the corresponding homogeneous particles. This reveals the significant advantage of JPs for the stabilization of emulsions and foams.

  4. An overview of the issues: physiological effects of bed rest and restricted physical activity

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.; Bloomfield, S. A.; Greenleaf, J. E.

    1997-01-01

    Reduction of exercise capacity with confinement to bed rest is well recognized. Underlying physiological mechanisms include dramatic reductions in maximal stroke volume, cardiac output, and oxygen uptake. However, bed rest by itself does not appear to contribute to cardiac dysfunction. Increased muscle fatigue is associated with reduced muscle blood flow, red cell volume, capillarization and oxidative enzymes. Loss of muscle mass and bone density may be reflected by reduced muscle strength and higher risk for injury to bones and joints. The resultant deconditioning caused by bed rest can be independent of the primary disease and physically debilitating in patients who attempt to reambulate to normal active living and working. A challenge to clinicians and health care specialists has been the identification of appropriate and effective methods to restore physical capacity of patients during or after restricted physical activity associated with prolonged bed rest. The examination of physiological responses to bed rest deconditioning and exercise training in healthy subjects has provided significant information to develop effective rehabilitation treatments. The successful application of acute exercise to enhance orthostatic stability, daily endurance exercise to maintain aerobic capacity, or specific resistance exercises to maintain musculoskeletal integrity rather than the use of surgical, pharmacological, and other medical treatments for clinical conditions has been enhanced by investigation and understanding of underlying mechanisms that distinguish physical deconditioning from the disease. This symposium presents an overview of cardiovascular and musculoskeletal deconditioning associated with reduced physical work capacity following prolonged bed rest and exercise training regimens that have proven successful in ameliorating or reversing these adverse effects.

  5. Overview of MSFC's Applied Fluid Dynamics Analysis Group Activities

    NASA Technical Reports Server (NTRS)

    Garcia, Roberto; Wang, Tee-See; Griffin, Lisa; Turner, James E. (Technical Monitor)

    2001-01-01

    This document is a presentation graphic which reviews the activities of the Applied Fluid Dynamics Analysis Group at Marshall Space Flight Center (i.e., Code TD64). The work of this group focused on supporting the space transportation programs. The work of the group is in Computational Fluid Dynamic tool development. This development is driven by hardware design needs. The major applications for the design and analysis tools are: turbines, pumps, propulsion-to-airframe integration, and combustion devices.

  6. ACTIVATION OF HAGEMAN FACTOR IN SOLID AND FLUID PHASES

    PubMed Central

    Cochrane, C. G.; Revak, S. D.; Wuepper, K. D.

    1973-01-01

    The activation of Hageman factor in solid and fluid phase has been analyzed. Activation of highly purified Hageman factor occurred after it interacted with and became bound to a negatively charged surface. Activation was observed in the absence of enzymes that are inhibitable with diisopropylfluorophosphate, phenyl methyl sulfonyl fluoride and ε-amino-n-caproic acid. The binding of [125I]Hageman factor to the negatively charged surface was markedly inhibited by plasma or purified plasma proteins. Activation of Hageman factor in solution (fluid phase) was obtained with kallikrein, plasmin, and Factor XI (plasma thromboplastin antecedent). Kallikrein was greater than 10 times more active in its ability to activate Hageman factor than plasmin and Factor XI. The data offer a plausible explanation for the finding that highly purified kallikrein promotes clotting of normal plasma. In addition, the combined results of this and previously reported data from this laboratory indicate that the reciprocal activation of Hageman factor by kallikrein in fluid phase is essential for normal rate of activation of the intrinsic-clotting, kinin-forming, and fibrinolytic systems. Activation of Hageman factor was associated with three different structural changes in the molecule: (a) Purified Hageman factor, activated on negatively charged surfaces retained its native mol wt of 80–90,000. Presumably a conformational change accompanied activation. (b) In fluid phase, activation with kallikrein and plasmin did not result in cleavage of large fragments of rabbit Hageman factor, although the activation required hydrolytic capacity of the enzymes. (c) Activation of human Hageman factor with kallikrein or plasmin was associated with cleavage of the molecule to 52,000, 40,000, and 28,000 mol wt fragments. Activation of rabbit Hageman factor with trypsin resulted in cleavage of the molecule into three fragments, each of 30,000 mol wt as noted previously. This major cleavage occurred

  7. Active Learning in Fluid Mechanics: Youtube Tube Flow and Puzzling Fluids Questions

    ERIC Educational Resources Information Center

    Hrenya, Christine M.

    2011-01-01

    Active-learning exercises appropriate for a course in undergraduate fluid mechanics are presented. The first exercise involves an experiment in gravity-driven tube flow, with small groups of students partaking in a contest to predict the experimental flow rates using the mechanical energy balance. The second exercise takes the form of an…

  8. Real-time measurement of volatile chemicals released by bed bugs during mating activities.

    PubMed

    Kilpinen, Ole; Liu, Dezhao; Adamsen, Anders Peter S

    2012-01-01

    In recent years, bed bug (Hemiptera: Cimicidae) problems have increased dramatically in many parts of the world, leading to a renewed interest in their chemical ecology. Most studies of bed bug semiochemicals have been based on the collection of volatiles over a period of time followed by chemical analysis. Here we present for the first time, a combination of proton transfer reaction mass spectrometry and video analysis for real-time measurement of semiochemicals emitted by isolated groups of bed bugs during specific behavioural activities. The most distinct peaks in the proton transfer reaction mass spectrometry recordings were always observed close to the termination of mating attempts, corresponding to the defensive emissions that bed bugs have been suspected to exploit for prevention of unwanted copulations. The main components of these emissions were (E)-2-hexenal and (E)-2-octenal recorded in ratios between 1:3 and 3:1. In the current study, the quantity varied over 1000 fold for both of the compounds with up to 40 µg total release in a single emission. Males also emit defensive compounds due to homosexual copulation attempts by other males, and no significant differences were observed in the ratio or the amount of the two components released from males or females. In summary, this study has demonstrated that combining proton-transfer-reaction mass spectrometry with video analysis can provide detailed information about semiochemicals emitted during specific behavioural activities.

  9. Real-Time Measurement of Volatile Chemicals Released by Bed Bugs during Mating Activities

    PubMed Central

    Kilpinen, Ole; Liu, Dezhao; Adamsen, Anders Peter S.

    2012-01-01

    In recent years, bed bug (Hemiptera: Cimicidae) problems have increased dramatically in many parts of the world, leading to a renewed interest in their chemical ecology. Most studies of bed bug semiochemicals have been based on the collection of volatiles over a period of time followed by chemical analysis. Here we present for the first time, a combination of proton transfer reaction mass spectrometry and video analysis for real-time measurement of semiochemicals emitted by isolated groups of bed bugs during specific behavioural activities. The most distinct peaks in the proton transfer reaction mass spectrometry recordings were always observed close to the termination of mating attempts, corresponding to the defensive emissions that bed bugs have been suspected to exploit for prevention of unwanted copulations. The main components of these emissions were (E)-2-hexenal and (E)-2-octenal recorded in ratios between 1∶3 and 3∶1. In the current study, the quantity varied over 1000 fold for both of the compounds with up to 40 µg total release in a single emission. Males also emit defensive compounds due to homosexual copulation attempts by other males, and no significant differences were observed in the ratio or the amount of the two components released from males or females. In summary, this study has demonstrated that combining proton-transfer-reaction mass spectrometry with video analysis can provide detailed information about semiochemicals emitted during specific behavioural activities. PMID:23227225

  10. Edge states in confined active fluids

    NASA Astrophysics Data System (ADS)

    Souslov, Anton; Vitelli, Vincenzo

    Recently, topologically protected edge modes have been proposed and realized in both mechanical and acoustic metamaterials. In one class of such metamaterials, Time-Reversal Symmetry is broken, and, to achieve this TRS breaking in mechanical and acoustic systems, an external energy input must be used. For example, motors provide a driving force that uses energy and, thus, explicitly break TRS. As a result, motors have been used as an essential component in the design of topological metamaterials. By contrast, we explore the design of topological metamaterials that use a class of far-from-equilibrium liquids, called polar active liquids, that spontaneously break TRS. We thus envision the confinement of a polar active liquid to a prescribed geometry in order to realize topological order with broken time-reversal symmetry. We address the design of the requisite geometries, for example a regular honeycomb lattice composed of annular channels, in which the active liquid may be confined. We also consider the physical character of the active liquid that, when introduced into the prescribed geometry, will spontaneously form the flow pattern of a metamaterial with topologically protected edge states. Finally, we comment on potential experimental realizations of such metamaterials.

  11. Evaluation of fructooligosaccharides separation using a fixed-bed column packed with activated charcoal.

    PubMed

    Kuhn, Raquel Cristine; Mazutti, Marcio A; Albertini, Lilian Buoro; Filho, Francisco Maugeri

    2014-05-25

    Recent studies have shown that the chromatographic separation of mixtures of saccharides may be improved by making use of activated charcoal, a promising low cost material for the separation of sugars, including fructooligosaccharides. In this work, the development of a methodology to separate fructooligosaccharides from glucose, fructose and sucrose, using a fixed bed column packed with activated charcoal is proposed. The influence of temperature, eluant concentration and step gradients were evaluated to increase the separation efficiency and fructooligosaccharide purity. The final degree of fructooligosaccharide purification and separation efficiency were about 94% and 3.03 respectively, using ethanol gradient concentration ranging from 3.5% to 15% (v/v) at 40°C. The fixed bed column packed with the activated charcoal was shown to be a promising alternative for sugar separation, mainly those rich in fructooligosaccharides, leading to solutions of acceptable degrees of purification.

  12. Physiological responses to prolonged bed rest and fluid immersion in man: A compendium of research (1974 - 1980)

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Silverstein, L.; Bliss, J.; Langenheim, V.; Rosson, H.; Chao, C.

    1982-01-01

    Water immersion and prolonged bed rest reproduce nearly all the physiological responses observed in astronauts in the weightless state. Related to actual weightlessness, given responses tend to occur sooner in immersion and later in bed rest. Much research was conducted on humans using these two techniques, especially by Russian scientists. Abstracts and annotations of reports that appeared in the literature from January 1974 through December 1980 are compiled and discussed.

  13. Integrated low emissions cleanup system for direct coal fueled turbines (moving bed, fluid bed contactor/ceramic filter). Twentieth quarterly status report, July--September 1992

    SciTech Connect

    Newby, R.A.; Alvin, M.A.; Bachovchin, D.M.; Yang, W.C.; Smeltzer, E.E.; Lippert, T.E.

    1992-10-20

    The United States Department of Energy, Morgantown Energy Research Center (DOE/METC), is sponsoring the development of direct coal-fired turbine power plants as part of their Heat Engines program. A major technical challenge remaining for the development of the direct coal-fired turbine is high-temperature combustion gas cleaning to meet environmental standards for sulfur oxides and particulate emissions, as well as to provide acceptable turbine life. The Westinghouse Electric Corporation, Science & Technology Center, is evaluating two Integrated Low Emissions Cleanup (ILEC) concepts that have been configured to meat this technical challenge: a baseline ceramic barrier filter ILEC concept, and a fluidized bed ILEC concept. These ILEC concepts simultaneously control sulfur, particulate, and alkali contaminants in the high-pressure combustion gases at turbine inlet temperatures up to 2300{degree}F. This document reports the status of a program in the nineteenth quarter to develop this ILEC technology for direct coal-fired turbine power plants.

  14. Dynamic bed reactor

    SciTech Connect

    Stormo, K.E.

    1996-07-02

    A dynamic bed reactor is disclosed in which a compressible open cell foam matrix is periodically compressed and expanded to move a liquid or fluid through the matrix. In preferred embodiments, the matrix contains an active material such as an enzyme, biological cell, chelating agent, oligonucleotide, adsorbent or other material that acts upon the liquid or fluid passing through the matrix. The active material may be physically immobilized in the matrix, or attached by covalent or ionic bonds. Microbeads, substantially all of which have diameters less than 50 microns, can be used to immobilize the active material in the matrix and further improve reactor efficiency. A particularly preferred matrix is made of open cell polyurethane foam, which adsorbs pollutants such as polychlorophenol or o-nitrophenol. The reactors of the present invention allow unidirectional non-laminar flow through the matrix, and promote intimate exposure of liquid reactants to active agents such as microorganisms immobilized in the matrix. 27 figs.

  15. Dynamic bed reactor

    SciTech Connect

    Stormo, Keith E.

    1996-07-02

    A dynamic bed reactor is disclosed in which a compressible open cell foam matrix is periodically compressed and expanded to move a liquid or fluid through the matrix. In preferred embodiments, the matrix contains an active material such as an enzyme, biological cell, chelating agent, oligonucleotide, adsorbent or other material that acts upon the liquid or fluid passing through the matrix. The active material may be physically immobilized in the matrix, or attached by covalent or ionic bonds. Microbeads, substantially all of which have diameters less than 50 microns, can be used to immobilize the active material in the matrix and further improve reactor efficiency. A particularly preferred matrix is made of open cell polyurethane foam, which adsorbs pollutants such as polychlorophenol or o-nitrophenol. The reactors of the present invention allow unidirectional non-laminar flow through the matrix, and promote intimate exposure of liquid reactants to active agents such as microorganisms immobilized in the matrix.

  16. Integrated Low Emissions Cleanup system for direct coal fueled turbines (moving bed, fluid bed contactor/ceramic filter). Twenty-fifth quarterly report, October--December 1993

    SciTech Connect

    Newby, R.A.; Alvin, M.A.; Bachovchin, D.M.; Yang, W.C.; Smeltzer, E.E.; Lippert, T.E.

    1993-12-31

    The United States Department of Energy, Morgantown Energy Research Center (DOE/METC), is sponsoring the development of direct coal-fired turbine power plants as part of their Heat Engines program. A major technical challenge remaining for the development of the direct coal-fired turbine is high-temperature combustion gas cleaning to meet environmental standards for sulfur oxides and particulate emissions, as well as to provide acceptable turbine life. The Westinghouse Electric Corporation, Science & Technology Center, is evaluating two Integrated Low Emissions Cleanup (ILEC) concepts that have been reconfigured to meet this technical challenge: a baseline ceramic barrier filter ILEC concept, and a fluidized bed ILEC concept. These ILEC concepts simultaneously control sulfur, particulate, and alkali contaminants in the high-pressure combustion gases at turbine inlet temperatures up to 2300{degree}F. This document reports the status of a program in the twenty-fifth quarter to develop this ILEC technology for direct coal-fired turbine power plants.

  17. SO{sub 2} oxidation in a periodically operated trickle bed: Comparison of activated carbon catalysts

    SciTech Connect

    Lee, Joong Kee; Hudgins, R.R.; Silveston, P.L.

    1996-12-31

    Catalytic activities of two different activated carbons, BPL{trademark} and Centaur{trademark} catalysts (Calgon Carbon Corp.), were compared in a periodically operated trickle-bed reactor for SO{sub 2} oxidation by varying the cycle period and split. In an effort to characterize the carbon surface, differential thermogravimetric analysis and TPD were used to observe oxygen functional groups. The Centaur catalyst, which appears to have a more suitable density of oxygen functional groups, has the higher catalytic activity for SO{sub 2} oxidation. 8 refs., 8 figs., 1 tab.

  18. Kinetic studies of elemental mercury adsorption in activated carbon fixed bed reactor.

    PubMed

    Skodras, G; Diamantopoulou, Ir; Pantoleontos, G; Sakellaropoulos, G P

    2008-10-01

    Activated carbons are suitable materials for Hg(0) adsorption in fixed bed operation or in injection process. The fixed bed tests provide good indication of activated carbons effectiveness and service lives, which depend on the rates of Hg(0) adsorption. In order to correlate fixed bed properties and operation conditions, with their adsorptive capacity and saturation time, Hg(0) adsorption tests were realized in a bench-scale unit, consisted of F400 activated carbon fixed bed reactor. Hg(0) adsorption tests were conducted at 50 degrees C, under 0.1 and 0.35 ng/cm(3) Hg(0) initial concentrations and with carbon particle sizes ranging between 75-106 and 150-250 microm. Based on the experimental breakthrough data, kinetic studies were performed to investigate the mechanism of adsorption and the rate controlling steps. Kinetic models evaluated include the Fick's intraparticle diffusion equation, the pseudo-first order model, the pseudo-second order model and Elovich kinetic equation. The obtained experimental results revealed that the increase in particle size resulted in significant decrease of breakthrough time and mercury adsorptive capacity, due to the enhanced internal diffusion limitations and smaller external mass transfer coefficients. Additionally, higher initial mercury concentrations resulted in increased breakthrough time and mercury uptake. From the kinetic studies results it was observed that all the examined models describes efficiently Hg(0) breakthrough curves, from breakpoint up to equilibrium time. The most accurate prediction of the experimental data was achieved by second order model, indicating that the chemisorption rate seems to be the controlling step in the procedure. However, the successful attempt to describe mercury uptake with Fick's diffusion model and the first order kinetic model, reveals that the adsorption mechanism studied was complex and followed both surface adsorption and particle diffusion.

  19. Use of wood-based materials in beef bedded manure packs: 2. Effect on odorous volatile organic compounds, odor activity value, , and nutrient concentrations.

    PubMed

    Spiehs, Mindy J; Brown-Brandl, Tami M; Berry, Elaine D; Wells, James E; Parker, David B; Miller, Daniel N; Jaderborg, Jeffrey P; DiCostanzo, Alfred

    2014-07-01

    The objectives of this study were to determine the effects of three types of wood-based bedding materials (kiln-dried pine wood chips, dry cedar chips, and green cedar chips) and corn stover on the concentration of odorous volatile organic compounds (VOCs) and total in bedded pack material. Four bedded packs of each bedding material were maintained for two 42-d periods ( = 32; eight replicates/bedding material). Straight- and branched-chained fatty acids, aromatic compounds, and sulfide compounds were measured from the headspace above each bedded pack. Green cedar bedding had the highest concentration of odorous VOCs, and pine chip bedding had the lowest ( < 0.01). Calculated odor activity values were highest for green cedar bedding, followed by dry cedar, corn stover, and pine chip bedding. As the bedded packs aged, the concentration of odorous VOCs increased, particularly in the bedded packs containing green cedar chips and dry cedar chips. Total concentrations increased from Days 0 to 21 and then began to decline and were similar among all bedding materials ( < 0.10). Results of this study indicate that producers using a long-term bedded pack management in their facility may benefit from using pine chips because they do not appear to increase odor over time. Cedar-based bedding materials may be better suited for a scrape-and-haul system, where the bedded pack is removed after 1 or 2 wk. Total concentrations did not differ between any of the four bedding materials over time.

  20. Competitive adsorption of furfural and phenolic compounds onto activated carbon in fixed bed column.

    PubMed

    Sulaymon, Abbas H; Ahmed, Kawther W

    2008-01-15

    For a multicomponent competitive adsorption of furfural and phenolic compounds, a mathematical model was builtto describe the mass transfer kinetics in a fixed bed column with activated carbon. The effects of competitive adsorption equilibrium constant, axial dispersion, external mass transfer, and intraparticle diffusion resistance on the breakthrough curve were studied for weakly adsorbed compound (furfural) and strongly adsorbed compounds (parachlorophenol and phenol). Experiments were carried out to remove the furfural and phenolic compound from aqueous solution. The equilibrium data and intraparticle diffusion coefficients obtained from separate experiments in a batch adsorber, by fitting the experimental data with theoretical model. The results show that the mathematical model includes external mass transfer and pore diffusion using nonlinear isotherms and provides a good description of the adsorption process for furfural and phenolic compounds in a fixed bed adsorber.

  1. A packed bed membrane reactor for production of biodiesel using activated carbon supported catalyst.

    PubMed

    Baroutian, Saeid; Aroua, Mohamed K; Raman, Abdul Aziz A; Sulaiman, Nik M N

    2011-01-01

    In this study, a novel continuous reactor has been developed to produce high quality methyl esters (biodiesel) from palm oil. A microporous TiO2/Al2O3 membrane was packed with potassium hydroxide catalyst supported on palm shell activated carbon. The central composite design (CCD) of response surface methodology (RSM) was employed to investigate the effects of reaction temperature, catalyst amount and cross flow circulation velocity on the production of biodiesel in the packed bed membrane reactor. The highest conversion of palm oil to biodiesel in the reactor was obtained at 70 °C employing 157.04 g catalyst per unit volume of the reactor and 0.21 cm/s cross flow circulation velocity. The physical and chemical properties of the produced biodiesel were determined and compared with the standard specifications. High quality palm oil biodiesel was produced by combination of heterogeneous alkali transesterification and separation processes in the packed bed membrane reactor.

  2. Combining microwave resonance technology to multivariate data analysis as a novel PAT tool to improve process understanding in fluid bed granulation.

    PubMed

    Lourenço, Vera; Herdling, Thorsten; Reich, Gabriele; Menezes, José C; Lochmann, Dirk

    2011-08-01

    A set of 192 fluid bed granulation batches at industrial scale were in-line monitored using microwave resonance technology (MRT) to determine moisture, temperature and density of the granules. Multivariate data analysis techniques such as multiway partial least squares (PLS), multiway principal component analysis (PCA) and multivariate batch control charts were applied onto collected batch data sets. The combination of all these techniques, along with off-line particle size measurements, led to significantly increased process understanding. A seasonality effect could be put into evidence that impacted further processing through its influence on the final granule size. Moreover, it was demonstrated by means of a PLS that a relation between the particle size and the MRT measurements can be quantitatively defined, highlighting a potential ability of the MRT sensor to predict information about the final granule size. This study has contributed to improve a fluid bed granulation process, and the process knowledge obtained shows that the product quality can be built in process design, following Quality by Design (QbD) and Process Analytical Technology (PAT) principles.

  3. Experimental investigation of synthetic gas composition in a two-stage fluidized bed gasification process: effect of activated carbon as bed material.

    PubMed

    Kuo, Jia-Hong; Lin, Chiou-Liang; Chang, Tsung-Jen; Weng, Wang-Chang; Liu, JingYong

    2017-05-01

    In this study, a two-stage fluidized bed gasifier was used to investigate the effect of the equivalence ratio (ER) and steam/biomass ratio (S/B) on the synthetic gas distribution while activated carbon (AC) was added as the bed material in secondary gasifier (Stage II). The experimental results showed that when the empty bed (without the bed material) was used for the Stage II reaction, the hydrogen (H2) content in the synthetic gas emitted from the Stage II reactor was 2-3 mol% higher than that from the first-stage gasifier (Stage I). It was supposed that using the Stage II reactor prolongs the reaction time and thereby increases the H2 production. Besides, when the AC was added in the Stage II gasifier, the H2 concentration, the total gas yield, and gas heating value reached their maximum (30 mol%) when ER and S/B were 0.3 and 1.5, respectively.

  4. Assessing Microbial Activity in Marcellus Shale Hydraulic Fracturing Fluids

    NASA Astrophysics Data System (ADS)

    Wishart, J. R.; Morono, Y.; Itoh, M.; Ijiri, A.; Hoshino, T.; Inagaki, F.; Verba, C.; Torres, M. E.; Colwell, F. S.

    2014-12-01

    Hydraulic fracturing (HF) produces millions of gallons of waste fluid which contains a microbial community adapted to harsh conditions such as high temperatures, high salinities and the presence of heavy metals and radionuclides. Here we present evidence for microbial activity in HF production fluids. Fluids collected from a Marcellus shale HF well were supplemented with 13C-labeled carbon sources and 15N-labeled ammonium at 25°C under aerobic or anaerobic conditions. Samples were analyzed for 13C and 15N incorporation at sub-micrometer scale by ion imaging with the JAMSTEC NanoSIMS to determine percent carbon and nitrogen assimilation in individual cells. Headspace CO2 and CH4 were analyzed for 13C enrichment using irm-GC/MS. At 32 days incubation carbon assimilation was observed in samples containing 1 mM 13C-labeled glucose under aerobic and anaerobic conditions with a maximum of 10.4 and 6.5% total carbon, respectively. Nitrogen assimilation of 15N ammonium observed in these samples were 0.3 and 0.8% of total nitrogen, respectively. Head space gas analysis showed 13C enrichment in CH4 in anaerobic samples incubated with 1mM 13C-labeled bicarbonate (2227 ‰) or methanol (98943 ‰). Lesser 13C enrichment of CO2 was observed in anaerobic samples containing 1 mM 13C-labeled acetate (13.7 ‰), methanol (29.9 ‰) or glucose (85.4 ‰). These results indicate metabolic activity and diversity in microbial communities present in HF flowback fluids. The assimilation of 13C-labeled glucose demonstrates the production of biomass, a critical part of cell replication. The production of 13CO2 and 13CH4 demonstrate microbial metabolism in the forms of respiration and methanogenesis, respectively. Methanogenesis additionally indicates the presence of an active archaeal community. This research shows that HF production fluid chemistry does not entirely inhibit microbial activity or growth and encourages further research regarding biogeochemical processes occurring in

  5. Modeling of mercury sorption by activated carbon in a confined, a semi-fluidized, and a fluidized bed.

    PubMed

    Ho, T C; Kobayashi, N; Lee, Y K; Lin, C J; Hopper, J R

    2002-01-01

    A process model was developed to simulate elemental mercury sorption by activated carbon in three distinct beds, namely a confined, a semi-fluidized, and a fluidized bed. The model involved the coupling of a kinetic model based on the mechanisms of surface equilibrium and external mass transfer, and a material balance model based on the tank-in-series approach. For surface equilibrium, three different equilibrium laws were used in the model, namely the Henry's Law, the Langmuir isotherm and the Freundlich isotherm. Literature mercury sorption data were used to determine the best-fit values of parameters for these equilibrium expressions. The parameter-fitted model was then used to simulate mercury sorption processes in the three distinct beds. The simulation parameters were mercury concentration, gas flow rate, adsorption temperature and the degree of semi-fluidization. The simulation results have indicated that the model is capable of describing the literature available mercury sorption data. All the three surface equilibrium laws appear to simulate the adsorption profiles equally well mainly because the sorption process occurs in an extremely low concentration range. The simulation results for the three distinct beds have suggested that the confined bed has the best mercury control performance; however, it generates the highest pressure-drop across the bed. A fluidized bed creates the least pressure drop; however, its sorption performance is poor. A semi-fluidized bed offers acceptable performance with affordable pressure-drops and can be a practical candidate for the process.

  6. Three-Dimensional Simulation of a Vibrofluidized Bed with the Use of a Two-Fluid Model of Granular Gas

    NASA Astrophysics Data System (ADS)

    Kamenetskii, E. S.; Orlova, N. S.; Tagirov, A. M.; Volik, M. V.

    2016-11-01

    We present the results of three-dimensional calculations of the degree of expansion of a vibrofluidized bed that were obtained with the aid of the twoPhaseEulerFoam solver of a freely accessible OpenFOAM package and the data of experiments on vibrobubbling of relatively large dolomite particles. Satisfactory agreement is obtained between the results of numerical calculations and experimental data.

  7. Magnetorheological effect in a suspension with an active carrier fluid

    SciTech Connect

    Kashevskii, B.E.; Kordonskii, V.I.; Prokhorov, I.V.

    1988-07-01

    The main quantitative laws governing the magnetorheological effect in a magnetorheological suspension with an active carrier liquid were established. The family of flow curves obtained for several samples of suspensions of one type of nonmagnetic particle was analyzed. Particles were suspended in a magnetic fluid of the magnetite-kerosite type. The main goal was to establish the law governing rheological similarity by generalizing experimental data with a universal relation while employing a small amount of initial data on the system. The data included the law of magnetization of the magnetic carrier fluid, the law of change in its viscosity in the field, and the law of change in the viscosity of the magnetorheological suspension/active carrier liquid system with an increase in the concentration of nonmagnetic particles in a zero field.

  8. Peptic ulcer perforation: sonographic imaging of active fluid leakage.

    PubMed

    Minardos, Ioannis; Ioannis, Minardos; Ziogana, Dimitra; Dimitra, Ziogana; Hristopoulos, Hristos; Hristos, Hristopoulos; Dermitzakis, Ioannis; Ioannis, Dermitzakis

    2006-01-01

    Sonography is not the method of choice for the evaluation of suspected peptic ulcer perforation (PUP). However, indirect sonographic signs and direct visualization of PUP have been reported by several authors in recent years. We report a case of an elderly woman who presented with severe abdominal pain and positive rebound sign, in whom abdominal sonography demonstrated indirect signs of PUP, the site of perforation, and active air fluid leakage through the perforated anterior prepyloric antral wall.

  9. Enabling Novel Minimally-Actuated Robotic Capabilities Through Active Fluids

    DTIC Science & Technology

    2013-07-25

    journals : 1. Ahmed Helal. Society of Rheology Meeting, Feb 2013, "Design of Integrated ER valves" 2. Boston Dynamics Active Fluids Program: IEEE RAS...adhesive climbers. (a) Papers published in peer-reviewed journals (N/A for none) Enter List of papers submitted or published that acknowledge ARO support...from the start of the project to the date of this printing. List the papers, including journal references, in the following categories: Received

  10. Fluid inclusion analysis of twinned selenite gypsum beds from the Miocene of the Madrid basin (Spain). Implication on dolomite bioformation

    NASA Astrophysics Data System (ADS)

    Ayllón-Quevedo, F.; Souza-Egipsy, V.; Sanz-Montero, M. E.; Rodríguez-Aranda, J. P.

    2007-09-01

    This research work is centred on continental lacustrine gypsum deposits of Miocene age cropping out in the easternmost part of the Madrid Basin. These gypsum deposits, accumulated in a continental saline lake, are characterized by a spectacular, distinctive Christmas-tree morphology and a peculiar dolomite replacement. A combination of microscopic (petrography and scanning electron microscopy) and analytical techniques (fluid inclusion microthermometry, X-ray energy dispersive spectroscopy and X-ray diffractometry) was used in order to study the crystallographic distribution and the composition of the fluid inclusions within the gypsum. The objectives were to characterize the continental brine from which the mineral precipitated, and to detect mineral and element traces that could indicate early diagenetic processes altering the gypsum deposits. Data from primary fluid inclusions indicated that gypsum precipitated from an aqueous fluid (lake water) of low to moderate total salinity (between 20 and 90 g/L NaCl). Secondary fluid inclusions represent interstitial lake brine in contact with gypsum, slightly enriched in total salt content as crystal formation proceeded. Textural, ultrastructural and microanalytical analysis indicate that the presence of dolomite precipitates inside the gypsum layers is related to the microbial colonization of the gypsum deposits and the biomineralization of the cell walls and extracellular polymeric substances around the cells. Our investigation emphasizes necessity of a multidisciplinary approach to assess geobiological processes.

  11. Modeling the transition between upper plane bed regime and sheet flow without an active layer formulation. Preliminary results.

    NASA Astrophysics Data System (ADS)

    Viparelli, E.; Hernandez Moreira, R. R.; Blom, A.

    2015-12-01

    A perusal of the literature on bedload transport revealed that, notwithstanding the large number of studies on bedform morphology performed in the past decades, the upper plane bed regime has not been thoroughly investigated and the distinction between the upper plane bed and sheet flow transport regimes is still poorly defined. Previous experimental work demonstrated that the upper plane bed regime is characterized by long wavelength and small amplitude bedforms that migrate downstream. These bedforms, however, were not observed in experiments on sheet flow transport suggesting that the upper plane bed and the sheet flow are two different regimes. We thus designed and performed experiments in a sediment feed flume in the hydraulic laboratory of the Department of Civil and Environmental Engineering at the University of South Carolina at Columbia to study the transition from upper plane bed to sheet flow regime. Periodic measurements of water surface and bed elevation, bedform geometry and thicknesses of the bedload layer were performed by eyes, and with cameras, movies and a system of six ultrasonic probes that record the variations of bed elevation at a point over time. We used the time series of bed elevations to determine the probability functions of bed elevation. These probability functions are implemented in a continuous model of river morphodynamics, i.e. a model that does not use the active layer approximation to describe the sediment fluxes between the bedload and the deposit and that should thus be able to capture the details of the vertical and streamwise variation of the deposit grain size distribution. This model is validated against the experimental results for the case of uniform material. We then use the validated model in the attempt to study if and how the spatial distribution of grain sizes in the deposit changes from upper plane bed regime to sheet flow and if these results are influenced by the imposed rates of base level rise.

  12. Alpha-mannosidase activity in stallion epididymal fluid and spermatozoa.

    PubMed

    Retamal, C A; Dias, A J B; Brasil, F C; Lanzana, F R; López, M L

    2012-07-15

    The expression of α-D-mannosidase activity was fluorometrically and electrophoretically assessed in spermatozoa, epididymal fluid and homogenates of stallion epididymal tissue. Enzyme activity had regional differences; it was higher (P<0.05) in samples from the cauda epididymal region than in samples from the proximal caput region (largely composed of efferent ducts). Based on enzyme activity, as a function of pH of the assay substrate, electrophoretic analysis in native and native/SDS-PAGE conditions, and the effect of inhibitors or activators, we inferred the presence of at least two catalytically active forms of α-D-mannosidase. The neutral form of the enzyme (α-mannosidase II) was activated by Co2+, whereas the acid form (optimum pH 3.5 to 4.0) was sensitive to swainsonine (an inhibitor of α-mannosidase I), stabilized or stimulated by Zn2+, and not activated by Co2+ (activator of the neutral form). The activity of the acid form of the enzyme was highest in the epididymal fluid, where it seemed to be mainly in a secretory form. This form of the enzyme may have a role in plasma membrane remodeling associated with sperm maturation. In contrast, the activity of α-mannosidase II was higher in mature spermatozoa. It has been postulated that α-mannosidase II may act as a receptor in the recognition and binding of the complementary carbohydrate moieties present on the zona pellucida. With non-denaturing electrophoresis, α-D-mannosidase had an electrophoretic mobility of 0.35 and 0.24. When resolved by 1D and 2D SDS-PAGE (under denaturing conditions) the enzyme had a major protein band of molecular weight 154 kDa in spermatozoa and epididymal samples. Based on its properties under native conditions, we inferred that this enzyme might interact with other proteins and form transitory aggregates.

  13. Biomechanics-based active control of bedding support properties and its influence on sleep.

    PubMed

    Van Deun, D; Verhaert, V; Willemen, T; Wuyts, J; Verbraecken, J; Exadaktylos, V; Haex, B; Vander Sloten, J

    2012-01-01

    Proper body support plays an import role in the recuperation of our body during sleep. Therefore, this study uses an automatically adapting bedding system that optimises spinal alignment throughout the night by altering the stiffness of eight comfort zones. The aim is to investigate the influence of such a dynamic sleep environment on objective and subjective sleep parameters. The bedding system contains 165 sensors that measure mattress indentation. It also includes eight actuators that control the comfort zones. Based on the measured mattress indentation, body movements and posture changes are detected. Control of spinal alignment is established by fitting personalized human models in the measured indentation. A total of 11 normal sleepers participated in this study. Sleep experiments were performed in a sleep laboratory where subjects slept three nights: a first night for adaptation, a reference night and an active support night (in counterbalanced order). Polysomnographic measurements were recorded during the nights, combined with questionnaires aiming at assessing subjective information. Subjective information on sleep quality, daytime quality and perceived number of awakenings shows significant improvements during the active support (ACS) night. Objective results showed a trend towards increased slow wave sleep. On the other hand, it was noticed that % N1-sleep was significantly increased during ACS night, while % N2-sleep was significantly decreased. No prolonged N1 periods were found during or immediately after steering.

  14. The application of preparative batch HPLC, supercritical fluid chromatography, steady-state recycling, and simulated moving bed for the resolution of a racemic pharmaceutical intermediate.

    PubMed

    Yan, Tony Q; Orihuela, Carlos; Swanson, David

    2008-02-01

    This article discusses the chromatographic resolution of a racemic pharmaceutical intermediate. Preparative batch high performance liquid chromatography (HPLC), supercritical fluid chromatography (SFC), steady-state recycling (SSR), and simulated moving bed (SMB) were used to resolve a total of 12.2 kg of a racemic pharmaceutical intermediate. In this study, a first batch of 0.8 kg of racemate was separated on the preparative batch HPLC and SFC, and subsequently another 5.9 kg of racemate was separated on the SSR. Lastly, a third batch of 5.5 kg was separated on the SMB. The separation conditions and results of these techniques are discussed. The productivities and solvent costs of SFC versus HPLC are compared. The productivities and solvent costs of SMB, SSR, and HPLC are also compared. The analytical method development and process optimization of these processes are also discussed in this article.

  15. Spontaneous and specific activation of chemical bonds in macromolecular fluids.

    PubMed

    Park, Insun; Shirvanyants, David; Nese, Alper; Matyjaszewski, Krzysztof; Rubinstein, Michael; Sheiko, Sergei S

    2010-09-08

    Mechanical activation of chemical bonds typically involves the application of external forces, which implies a broad distribution of bond tensions. We demonstrate that controlling the flow profile of a macromolecular fluid generates and delineates mechanical force concentration, enabling a hierarchical activation of chemical bonds on different length scales from the macroscopic to the molecular. Bond tension is spontaneously generated within brushlike macromolecules as they spread on a solid substrate. The molecular architecture creates an uneven distribution of tension in the covalent bonds, leading to spatially controlled bond scission. By controlling the flow rate and the gradient of the film pressure, one can sever the flowing macromolecules with high precision. Specific chemical bonds are activated within distinct macromolecules located in a defined area of a thin film. Furthermore, the flow-controlled loading rate enables quantitative analysis of the bond activation parameters.

  16. Application of computational fluid dynamics for the simulation of cryogenic molecular sieve bed absorber of hydrogen isotopes recovery system for Indian LLCB-TBM

    SciTech Connect

    Gayathri Devi, V.; Sircar, A.; Sarkar, B.

    2015-03-15

    One of the most challenging tasks in the design of the fuel cycle system lies in the effective design of Tritium Extraction System (TES) which involves proper extraction and purification of tritium in the fuel cycle of the fusion reactor. Indian Lead Lithium cooled Ceramic Breeder Test Blanket Module (LLCB-TBM) would extract hydrogen isotopes through Cryogenic Molecular Sieve Bed (CMSB) adsorber system. A prototype Hydrogen Isotopes Recovery System (HIRS) is being developed to validate the concepts for tritium extraction by adsorption mass transfer mechanism. In this study, a design model has been developed and analyzed to simulate the adsorption mass transfer kinetics in a fixed bed adsorption column. The simulation leads primarily to effective design of HIRS, which is a state-of-the-art technology. The paper describes the process simulation approach and the results of Computational Fluid Dynamics (CFD) analysis. The effects of different operating conditions are studied to investigate their influence on the hydrogen isotopes adsorption capacity. The results of the present simulation study would be used to understand the best optimized transport phenomenon before realizing the TES as a system for LLCB-TBM. (authors)

  17. Stopping the Slide: How Hospital Bed Design Can Minimize Active and Passive Patient Migration.

    PubMed

    Davis, Kermit G; Kotowski, Susan E; Coombs, Matthew T

    Patient migration, or the amount of movement toward the foot of the bed, has been shown to significantly vary because of the mechanical design differences in hospital beds. Previously, the amount of migration was measured immediately following head-of-bed articulation in healthy subjects. This study not only evaluates how much migration occurs immediately after head-of-bed articulation but also measures additional migration during a standard 2-hour repositioning period in subjects with limited mobility.

  18. Effect of bed vicinity on vortex shedding and force coefficients of fluid flow on an offshore pipeline

    NASA Astrophysics Data System (ADS)

    Namazi-saleh, Fatemeh; Kurian, Velluruzhathil John; Mustaffa, Zahiraniza; Tahan, Mohammadreza; Kim, Dokyun

    2017-03-01

    The effect of rigid bed proximity on flow parameters and hydrodynamic loads in offshore pipelines exposed to turbulent flow is investigated numerically. The Galerkin finite volume method is employed to solve the unsteady incompressible 2D Navier-Stokes equations. The large eddy simulation turbulence model is solved using the artificial compressibility method and dual time-stepping approach. The proposed algorithm is developed for a wide range of turbulent flows with Reynolds numbers of 9500 to 1.5×104. Evaluation of the developed numerical model shows that the proposed technique is capable of properly predicting hydrodynamic forces and simulating the flow pattern. The obtained results show that the lift and drag coefficients are strongly affected by the gap ratio. The mean drag coefficient slightly increases as the gap ratio increases, although the mean lift coefficient rapidly decreases. The vortex shedding suppression happen at the gap ratio of less than 0.2.

  19. Effect of bed vicinity on vortex shedding and force coefficients of fluid flow on an offshore pipeline

    NASA Astrophysics Data System (ADS)

    Namazi-saleh, Fatemeh; Kurian, Velluruzhathil John; Mustaffa, Zahiraniza; Tahan, Mohammadreza; Kim, Dokyun

    2017-01-01

    The effect of rigid bed proximity on flow parameters and hydrodynamic loads in offshore pipelines exposed to turbulent flow is investigated numerically. The Galerkin finite volume method is employed to solve the unsteady incompressible 2D Navier-Stokes equations. The large eddy simulation turbulence model is solved using the artificial compressibility method and dual time-stepping approach. The proposed algorithm is developed for a wide range of turbulent flows with Reynolds numbers of 9500 to 1.5×104. Evaluation of the developed numerical model shows that the proposed technique is capable of properly predicting hydrodynamic forces and simulating the flow pattern. The obtained results show that the lift and drag coefficients are strongly affected by the gap ratio. The mean drag coefficient slightly increases as the gap ratio increases, although the mean lift coefficient rapidly decreases. The vortex shedding suppression happen at the gap ratio of less than 0.2.

  20. Evidence for Methyl-Compound-Activated Life in Coal Bed System 2 km Below Sea Floor

    NASA Astrophysics Data System (ADS)

    Trembath-reichert, E.; Morono, Y.; Dawson, K.; Wanger, G.; Bowles, M.; Heuer, V.; Hinrichs, K. U.; Inagaki, F.; Orphan, V. J.

    2014-12-01

    IODP Expedition 337 set the record for deepest marine scientific drilling down to 2.4 kmbsf. This cruise also had the unique opportunity to retrieve deep cores from the Shimokita coal bed system in Japan with the aseptic and anaerobic conditions necessary to look for deep life. Onboard scientists prepared nearly 1,700 microbiology samples shared among five different countries to study life in the deep biosphere. Samples spanned over 1 km in sampling depths and include representatives of shale, sandstone, and coal lithologies. Findings from previous IODP and deep mine expeditions suggest the genetic potential for methylotrophy in the deep subsurface, but it has yet to be observed in incubations. A subset of Expedition 337 anoxic incubations were prepared with a range of 13C-methyl substrates (methane, methylamine, and methanol) and maintained near in situ temperatures. To observe 13C methyl compound metabolism over time, we monitored the δ13C of the dissolved inorganic carbon (by-product of methyl compound metabolism) over a period of 1.5 years. Elemental analysis (EA), ion chromatograph (IC), 13C volatile fatty acid (VFA), and mineral-associated microscopy data were also collected to constrain initial and endpoint conditions in these incubations. Our geochemical evidence suggests that the coal horizon incubated with 13C-methane showed the highest activity of all methyl incubations. This provides the first known observation of methane-activated metabolism in the deep biosphere, and suggests there are not only active cells in the deeply buried terrigenous coal bed at Shimokita, but the presence of a microbial community activated by methylotrophic compounds.

  1. How to dose powdered activated carbon in deep bed filtration for efficient micropollutant removal.

    PubMed

    Altmann, Johannes; Ruhl, Aki S; Sauter, Daniel; Pohl, Julia; Jekel, Martin

    2015-07-01

    Direct addition of powdered activated carbon (PAC) to the inlet of a deep bed filter represents an energy- and space-saving option to remove organic micropollutants (OMPs) during advanced wastewater treatment or drinking water purification. In this lab-scale study, continuous dosing, preconditioning a filter with PAC and combinations thereof were investigated as possible dosing modes with respect to OMP adsorption efficiency. Continuous dosing resulted in decreasing effluent concentrations with increasing filter runtime due to adsorption onto accumulating PAC in the filter bed. Approximately constant removal levels were achieved at longer filter runtimes, which were mainly determined by the dose of fresh PAC, rather than the total PAC amount embedded. The highest effluent concentrations were observed during the initial filtration stage. Meanwhile, preconditioning led to complete OMP adsorption at the beginning of filtration and subsequent gradual OMP breakthrough. PAC distribution in the pumice filter was determined by the loss on ignition of PAC and pumice and was shown to be relevant for adsorption efficiency. Preconditioning with turbulent upflow led to a homogenous PAC distribution and improved OMP adsorption significantly. Combining partial preconditioning and continuous dosing led to low initial effluent concentrations, but ultimately achieved concentrations similar to filter runs without preconditioning. Furthermore, a dosing stop prior to the end of filtration was suitable to increase PAC efficiency without affecting overall OMP removals.

  2. Deactivation model for the adsorption of trichloroethylene vapor on an activated carbon bed

    SciTech Connect

    Suyadal, Y.; Erol, M.; Oguz, H.

    2000-03-01

    In this work, the adsorption of trichloroethylene (TCE) vapor was investigated in a laboratory-scale packed-bed adsorber by using granular activated carbon (GAC) at constant pressure (101.3 kPa). The packed-bed adsorber (PBA) was operated batchwise with the charges of GAC particles in the ranges of 2.5--10.0 g for obtaining TCE breakthrough curves. Experiments were carried out at different temperatures (25.6 {le} T({degree}C) {le} 35.8) and TCE feedstock concentrations (6,350 {le} C (ppm TCE) {le} 7,950) within the range of space velocity (5,000 {le} {var_theta} (h{sup {minus}1}) {le} 17,000). The effects of TCE inlet concentration, operating temperature, and mass of adsorbent (m{sub Ads}) on the TCE breakthrough curves were investigated, respectively. The deactivation model (DM) was tested for these curves by using the analogy between the adsorption of TCE and the deactivation of catalyst particles. Observed adsorption rate constants (k{sub S}) and first-order deactivation rate constants (k{sub d}) were obtained from the model. It was found that the deactivation model describes the experimental breakthrough curves more accurately compared to the adsorption isotherms given in the literature.

  3. Removal of CO2 in a multistage fluidized bed reactor by diethanol amine impregnated activated carbon.

    PubMed

    Das, Dipa; Samal, Debi Prasad; Meikap, Bhim C

    2016-07-28

    To mitigate the emission of carbon dioxide (CO2), we have developed and designed a four-stage fluidized bed reactor. There is a counter current exchange between solid adsorbent and gas flow. In this present investigation diethanol amine (DEA) impregnated activated carbon made from green coconut shell was used as adsorbent. This type of adsorbent not only adsorbs CO2 due to the presence of pore but also chemically reacts with CO2 and form secondary zwitterions. Sampling and analysis of CO2 was performed using Orsat apparatus. The effect of initial CO2 concentration, gas velocity, solid rate, weir height etc. on removal efficiency of CO2 have been investigated and presented. The percentage removal of CO2 has been found close to 80% under low gas flow rate (0.188 m/s), high solid flow rate (4.12 kg/h) and weir height of 50 mm. From this result it has been found out that multistage fluidized bed reactor may be a suitable equipment for removal of CO2 from flue gas.

  4. Host Searching and Aggregation Activity of Recently Fed and Unfed Bed Bugs (Cimex lectularius L.)

    PubMed Central

    Reis, Matthew D.; Miller, Dini M.

    2011-01-01

    Groups of starved, virgin adult male or female bed bugs were stimulated to search for a host by the presence of a heated artificial feeder. Some of the bed bug groups were allowed to obtain a blood meal and some were not. After the removal of the feeder, bed bugs were observed throughout the scotophase to record their searching and aggregation behavior. Groups of male and female bed bugs that were unable to obtain a blood meal continued to search in the arena for the majority of the scotophase. Bed bugs that were able to obtain a blood meal returned to their shelter to aggregate 30 min after feeding. Overall, the proportion of bed bugs aggregating in shelters during the scotophase was significantly greater for those that had fed successfully than those that had not. However, all bed bugs, regardless of feeding status, began to return to shelters to aggregate 2 h prior to the photophase. PMID:26467621

  5. Host Searching and Aggregation Activity of Recently Fed and Unfed Bed Bugs (Cimex lectularius L.).

    PubMed

    Reis, Matthew D; Miller, Dini M

    2011-05-04

    Groups of starved, virgin adult male or female bed bugs were stimulated to search for a host by the presence of a heated artificial feeder. Some of the bed bug groups were allowed to obtain a blood meal and some were not. After the removal of the feeder, bed bugs were observed throughout the scotophase to record their searching and aggregation behavior. Groups of male and female bed bugs that were unable to obtain a blood meal continued to search in the arena for the majority of the scotophase. Bed bugs that were able to obtain a blood meal returned to their shelter to aggregate 30 min after feeding. Overall, the proportion of bed bugs aggregating in shelters during the scotophase was significantly greater for those that had fed successfully than those that had not. However, all bed bugs, regardless of feeding status, began to return to shelters to aggregate 2 h prior to the photophase.

  6. Cluster formation and drag reduction-proposed mechanism of particle recirculation within the partition column of the bottom spray fluid-bed coater.

    PubMed

    Wang, Li Kun; Heng, Paul Wan Sia; Liew, Celine Valeria

    2015-04-01

    Bottom spray fluid-bed coating is a common technique for coating multiparticulates. Under the quality-by-design framework, particle recirculation within the partition column is one of the main variability sources affecting particle coating and coat uniformity. However, the occurrence and mechanism of particle recirculation within the partition column of the coater are not well understood. The purpose of this study was to visualize and define particle recirculation within the partition column. Based on different combinations of partition gap setting, air accelerator insert diameter, and particle size fraction, particle movements within the partition column were captured using a high-speed video camera. The particle recirculation probability and voidage information were mapped using a visiometric process analyzer. High-speed images showed that particles contributing to the recirculation phenomenon were behaving as clustered colonies. Fluid dynamics analysis indicated that particle recirculation within the partition column may be attributed to the combined effect of cluster formation and drag reduction. Both visiometric process analysis and particle coating experiments showed that smaller particles had greater propensity toward cluster formation than larger particles. The influence of cluster formation on coating performance and possible solutions to cluster formation were further discussed.

  7. Trace elements affect methanogenic activity and diversity in enrichments from subsurface coal bed produced water.

    PubMed

    Unal, Burcu; Perry, Verlin Ryan; Sheth, Mili; Gomez-Alvarez, Vicente; Chin, Kuk-Jeong; Nüsslein, Klaus

    2012-01-01

    Microbial methane from coal beds accounts for a significant and growing percentage of natural gas worldwide. Our knowledge of physical and geochemical factors regulating methanogenesis is still in its infancy. We hypothesized that in these closed systems, trace elements (as micronutrients) are a limiting factor for methanogenic growth and activity. Trace elements are essential components of enzymes or cofactors of metabolic pathways associated with methanogenesis. This study examined the effects of eight trace elements (iron, nickel, cobalt, molybdenum, zinc, manganese, boron, and copper) on methane production, on mcrA transcript levels, and on methanogenic community structure in enrichment cultures obtained from coal bed methane (CBM) well produced water samples from the Powder River Basin, Wyoming. Methane production was shown to be limited both by a lack of additional trace elements as well as by the addition of an overly concentrated trace element mixture. Addition of trace elements at concentrations optimized for standard media enhanced methane production by 37%. After 7 days of incubation, the levels of mcrA transcripts in enrichment cultures with trace element amendment were much higher than in cultures without amendment. Transcript levels of mcrA correlated positively with elevated rates of methane production in supplemented enrichments (R(2) = 0.95). Metabolically active methanogens, identified by clone sequences of mcrA mRNA retrieved from enrichment cultures, were closely related to Methanobacterium subterraneum and Methanobacterium formicicum. Enrichment cultures were dominated by M. subterraneum and had slightly higher predicted methanogenic richness, but less diversity than enrichment cultures without amendments. These results suggest that varying concentrations of trace elements in produced water from different subsurface coal wells may cause changing levels of CBM production and alter the composition of the active methanogenic community.

  8. Trace Elements Affect Methanogenic Activity and Diversity in Enrichments from Subsurface Coal Bed Produced Water

    PubMed Central

    Ünal, Burcu; Perry, Verlin Ryan; Sheth, Mili; Gomez-Alvarez, Vicente; Chin, Kuk-Jeong; Nüsslein, Klaus

    2012-01-01

    Microbial methane from coal beds accounts for a significant and growing percentage of natural gas worldwide. Our knowledge of physical and geochemical factors regulating methanogenesis is still in its infancy. We hypothesized that in these closed systems, trace elements (as micronutrients) are a limiting factor for methanogenic growth and activity. Trace elements are essential components of enzymes or cofactors of metabolic pathways associated with methanogenesis. This study examined the effects of eight trace elements (iron, nickel, cobalt, molybdenum, zinc, manganese, boron, and copper) on methane production, on mcrA transcript levels, and on methanogenic community structure in enrichment cultures obtained from coal bed methane (CBM) well produced water samples from the Powder River Basin, Wyoming. Methane production was shown to be limited both by a lack of additional trace elements as well as by the addition of an overly concentrated trace element mixture. Addition of trace elements at concentrations optimized for standard media enhanced methane production by 37%. After 7 days of incubation, the levels of mcrA transcripts in enrichment cultures with trace element amendment were much higher than in cultures without amendment. Transcript levels of mcrA correlated positively with elevated rates of methane production in supplemented enrichments (R2 = 0.95). Metabolically active methanogens, identified by clone sequences of mcrA mRNA retrieved from enrichment cultures, were closely related to Methanobacterium subterraneum and Methanobacterium formicicum. Enrichment cultures were dominated by M. subterraneum and had slightly higher predicted methanogenic richness, but less diversity than enrichment cultures without amendments. These results suggest that varying concentrations of trace elements in produced water from different subsurface coal wells may cause changing levels of CBM production and alter the composition of the active methanogenic community. PMID

  9. Combustion in fluidized beds

    SciTech Connect

    Dry, F.J.; La Nauze, R.D. )

    1990-07-01

    Circulating fluidized-bed (CFB) combustion systems have become popular since the late 1970s, and, given the current level of activity in the area,it is clear that this technology has a stable future in the boiler market. For standard coal combustion applications, competition is fierce with mature pulverized-fuel-based (PF) technology set to maintain a strong profile. CFB systems, however, can be more cost effective than PF systems when emission control is considered, and, as CFB technology matures, it is expected that an ever-increasing proportion of boiler installations will utilize the CFB concept. CFB systems have advantages in the combustion of low-grade fuels such as coal waste and biomass. In competition with conventional bubbling beds, the CFB boiler often demonstrates superior carbon burn-out efficiency. The key to this combustion technique is the hydrodynamic behavior of the fluidized bed. This article begins with a description of the fundamental fluid dynamic behavior of the CFB system. This is followed by an examination of the combustion process in such an environment and a discussion of the current status of the major CFB technologies.

  10. Reliable activation to novel stimuli predicts higher fluid intelligence.

    PubMed

    Euler, Matthew J; Weisend, Michael P; Jung, Rex E; Thoma, Robert J; Yeo, Ronald A

    2015-07-01

    The ability to reliably respond to stimuli could be an important biological determinant of differences in fluid intelligence (Gf). However, most electrophysiological studies of Gf employ event-related potential (ERP) measures that average brain activity over trials, and hence have limited power to quantify neural variability. Time-frequency analyses can capture cross-trial variation in the phase of neural activity, and thus can help address the importance of neural reliability to differences in Gf. This study recruited a community sample of healthy adults and measured inter-trial phase clustering (ITPC), total spectral power, and ERP amplitudes elicited by Repeated and Novel non-target stimuli during two visual oddball tasks. Condition effects, relations among the EEG measures, and relations with Gf were assessed. Early visual responses to Repeated stimuli elicited higher ITPC, yet only ITPC elicited by Novel stimuli was associated with Gf. Analyses of spectral power further highlighted the contribution of phase consistency to the findings. The link between Gf and reliable responding to changing inputs suggests an important role for flexible resource allocation in fluid intellectual skills.

  11. Prolonged effect of fluid flow stress on the proliferative activity of mesothelial cells after abrupt discontinuation of fluid streaming

    SciTech Connect

    Aoki, Shigehisa; Ikeda, Satoshi; Takezawa, Toshiaki; Kishi, Tomoya; Makino, Junichi; Uchihashi, Kazuyoshi; Matsunobu, Aki; Noguchi, Mitsuru; Sugihara, Hajime; Toda, Shuji

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer Late-onset peritoneal fibrosis leading to EPS remains to be elucidated. Black-Right-Pointing-Pointer Fluid streaming is a potent factor for peritoneal fibrosis in PD. Black-Right-Pointing-Pointer We focused on the prolonged effect of fluid streaming on mesothelial cell kinetics. Black-Right-Pointing-Pointer A history of fluid streaming exposure promoted mesothelial proliferative activity. Black-Right-Pointing-Pointer We have thus identified a potent new factor for late-onset peritoneal fibrosis. -- Abstract: Encapsulating peritoneal sclerosis (EPS) often develops after transfer to hemodialysis and transplantation. Both termination of peritoneal dialysis (PD) and transplantation-related factors are risks implicated in post-PD development of EPS, but the precise mechanism of this late-onset peritoneal fibrosis remains to be elucidated. We previously demonstrated that fluid flow stress induced mesothelial proliferation and epithelial-mesenchymal transition via mitogen-activated protein kinase (MAPK) signaling. Therefore, we speculated that the prolonged bioactive effect of fluid flow stress may affect mesothelial cell kinetics after cessation of fluid streaming. To investigate how long mesothelial cells stay under the bioactive effect brought on by fluid flow stress after removal of the stress, we initially cultured mesothelial cells under fluid flow stress and then cultured the cells under static conditions. Mesothelial cells exposed to fluid flow stress for a certain time showed significantly high proliferative activity compared with static conditions after stoppage of fluid streaming. The expression levels of protein phosphatase 2A, which dephosphorylates MAPK, in mesothelial cells changed with time and showed a biphasic pattern that was dependent on the duration of exposure to fluid flow stress. There were no differences in the fluid flow stress-related bioactive effects on mesothelial cells once a certain time had passed

  12. Young asteroidal fluid activity revealed by absolute age from apatite in carbonaceous chondrite.

    PubMed

    Zhang, Ai-Cheng; Li, Qiu-Li; Yurimoto, Hisayoshi; Sakamoto, Naoya; Li, Xian-Hua; Hu, Sen; Lin, Yang-Ting; Wang, Ru-Cheng

    2016-09-29

    Chondritic meteorites, consisting of the materials that have formed in the early solar system (ESS), have been affected by late thermal events and fluid activity to various degrees. Determining the timing of fluid activity in ESS is of fundamental importance for understanding the nature, formation, evolution and significance of fluid activity in ESS. Previous investigations have determined the relative ages of fluid activity with short-lived isotope systematics. Here we report an absolute (207)Pb/(206)Pb isochron age (4,450±50 Ma) of apatite from Dar al Gani (DaG) 978, a type ∼3.5, ungrouped carbonaceous chondrite. The petrographic, mineralogical and geochemical features suggest that the apatite in DaG 978 should have formed during metamorphism in the presence of a fluid. Therefore, the apatite age represents an absolute age for fluid activity in an asteroidal setting. An impact event could have provided the heat to activate this young fluid activity in ESS.

  13. Young asteroidal fluid activity revealed by absolute age from apatite in carbonaceous chondrite

    NASA Astrophysics Data System (ADS)

    Zhang, Ai-Cheng; Li, Qiu-Li; Yurimoto, Hisayoshi; Sakamoto, Naoya; Li, Xian-Hua; Hu, Sen; Lin, Yang-Ting; Wang, Ru-Cheng

    2016-09-01

    Chondritic meteorites, consisting of the materials that have formed in the early solar system (ESS), have been affected by late thermal events and fluid activity to various degrees. Determining the timing of fluid activity in ESS is of fundamental importance for understanding the nature, formation, evolution and significance of fluid activity in ESS. Previous investigations have determined the relative ages of fluid activity with short-lived isotope systematics. Here we report an absolute 207Pb/206Pb isochron age (4,450+/-50 Ma) of apatite from Dar al Gani (DaG) 978, a type ~3.5, ungrouped carbonaceous chondrite. The petrographic, mineralogical and geochemical features suggest that the apatite in DaG 978 should have formed during metamorphism in the presence of a fluid. Therefore, the apatite age represents an absolute age for fluid activity in an asteroidal setting. An impact event could have provided the heat to activate this young fluid activity in ESS.

  14. Radioactive Demonstrations Of Fluidized Bed Steam Reforming (FBSR) With Hanford Low Activity Wastes

    SciTech Connect

    Jantzen, C. M.; Crawford, C. L.; Burket, P. R.; Bannochie, C. J.; Daniel, W. G.; Nash, C. A.; Cozzi, A. D.; Herman, C. C.

    2012-10-22

    Several supplemental technologies for treating and immobilizing Hanford low activity waste (LAW) are being evaluated. One immobilization technology being considered is Fluidized Bed Steam Reforming (FBSR) which offers a low temperature (700-750?C) continuous method by which wastes high in organics, nitrates, sulfates/sulfides, or other aqueous components may be processed into a crystalline ceramic (mineral) waste form. The granular waste form produced by co-processing the waste with kaolin clay has been shown to be as durable as LAW glass. The FBSR granular product will be monolithed into a final waste form. The granular component is composed of insoluble sodium aluminosilicate (NAS) feldspathoid minerals such as sodalite. Production of the FBSR mineral product has been demonstrated both at the industrial, engineering, pilot, and laboratory scales on simulants. Radioactive testing at SRNL commenced in late 2010 to demonstrate the technology on radioactive LAW streams which is the focus of this study.

  15. Adsorption interference in mixtures of trace contaminants flowing through activated carbon adsorber beds

    NASA Technical Reports Server (NTRS)

    Madey, R.; Photinos, P. J.

    1980-01-01

    Adsorption interference in binary and ternary mixtures of trace contaminants in a helium carrier gas flowing through activated carbon adsorber beds are studied. The isothermal transmission, which is the ratio of the outlet to the inlet concentration, of each component is measured. Interference between co-adsorbing gases occurs when the components are adsorbed strongly. Displacement of one component by another is manifested by a transmission greater than unity for the displaced component over some range of eluted volume. Interference is evidenced not only by a reduction of the adsorption capacity of each component in the mixture in comparison with the value obtained in a single-component experiment, but also by a change in the slope of the transmission curve of each component experiment.

  16. Modeling of moisture diffusivity, activation energy and energy consumption in fluidized bed drying of rough rice

    NASA Astrophysics Data System (ADS)

    Khanali, Majid; Banisharif, Alireza; Rafiee, Shahin

    2016-11-01

    The present work was an attempt to assess the effective moisture diffusivity, activation energy, and energy consumption of rough rice in a batch fluidized bed dryer. Drying experiments were conducted at drying air temperatures of 50, 60, and 70 °C, superficial fluidization velocities of 2.3, 2.5, and 2.8 m/s, and solids holdup of 1.32 kg. Drying kinetics showed that the whole fluidized bed drying of rough rice occurred in the falling rate period. The effective moisture diffusivity was described by an Arrhenius equation. The evaluated effective moisture diffusivity increased with drying air temperature and superficial fluidization velocity and was found to vary from 4.78 × 10-11 to 1.364 × 10-10 m2/s with R2 higher than 0.9643. The activation energy and the pre-exponential factor of Arrhenius equation were found to be in the range of 36.59-44.31 kJ/mol and 4.71 × 10-5-7.15 × 10-4 m2/s, respectively. Both maximum values of the specific energy consumption of 74.73 MJ/kg and the total energy need of 12.43 MJ were obtained at 60 °C drying air temperature and 2.8 m/s superficial fluidization velocity. Both minimum values of the specific energy consumption of 29.98 MJ/kg and the total energy need of 4.85 MJ were obtained under drying air temperature of 70 °C and superficial fluidization velocity of 2.3 m/s.

  17. Fluid dynamics of active heterogeneities in a mantle plume conduit

    NASA Astrophysics Data System (ADS)

    Farnetani, C. G.; Limare, A.; Hofmann, A. W.

    2015-12-01

    Laboratory experiments and numerical simulations indicate that the flow of a purely thermal plume preserves the azimuthal zonation of the source region, thus providing a framework to attribute a deep origin to the isotopic zonation of Hawaiian lavas. However, previous studies were limited to passive heterogeneities not affecting the flow. We go beyond this simplification by considering active heterogeneities which are compositionally denser, or more viscous, and we address the following questions: (1) How do active heterogeneities modify the axially symmetric velocity field of the plume conduit? (2) Under which conditions is the azimuthal zonation of the source region no longer preserved in the plume stem? (3) How do active heterogeneities deform during upwelling and what is their shape once at sublithospheric depths? We conducted both laboratory experiments, using a Particle Image Velocimetry (PIV) to calculate the velocity field, and high resolution three-dimensional simulations where millions of tracers keep track of the heterogeneous fluid. For compositionally denser heterogeneities we cover a range of buoyancy ratios 0fluid and η is viscosity. The initial heterogeneity has the arbitrary shape of a sphere and we vary its volume and its distance from the plume axis. We find that by increasing λ, the shape of the heterogeneity changes from filament-like to blob-like characterized by internal rotation and little stretching. By increasing B the heterogeneity tends to spread at the base of the plume stem and to rise as a tendril close to the axis, so that the initial zonation may be poorly preserved. We also find that the plume velocity field can be profoundly modified by active heterogeneities, and we explore the relation between strain rates and the evolving shape of the upwelling heterogeneity.

  18. Current Results and Proposed Activities in Microgravity Fluid Dynamics

    NASA Technical Reports Server (NTRS)

    Polezhaev, V. I.

    1996-01-01

    The Institute for Problems in Mechanics' Laboratory work in mathematical and physical modelling of fluid mechanics develops models, methods, and software for analysis of fluid flow, instability analysis, direct numerical modelling and semi-empirical models of turbulence, as well as experimental research and verification of these models and their applications in technological fluid dynamics, microgravity fluid mechanics, geophysics, and a number of engineering problems. This paper presents an overview of the results in microgravity fluid dynamics research during the last two years. Nonlinear problems of weakly compressible and compressible fluid flows are discussed.

  19. Three-component competitive adsorption model for fixed-bed and moving-bed granular activated carbon adsorbers. Part II. Model parameterization and verification

    SciTech Connect

    Lance C. Schideman; Benito J. Marinas; Vernon L. Snoeyink; Carlos Campos

    2006-11-01

    COMPSORB-GAC is a 3-component competitive adsorption kinetic model for granular activated carbon (GAC) adsorbers that was developed in Part I of this study, including a proposed procedure for determining model parameters in natural water applications with background natural organic matter (NOM). Part II of this study demonstrates the proposed parameterization procedure and validates the modeling approach by comparing predictions with experimental breakthrough curves at multiple empty-bed contact times for both fixed-bed and moving-bed reactors. The parameterization procedure consists of a set of independent, short-term experimental tests with fresh and batch preloaded adsorbents (using F-400 GAC, a coal-based adsorbent) and then data fitting using both classic and recently developed theoretical expressions. The model and parameterization procedure simplifies NOM into two fictive fractions (pore-blocking and strongly competing) and incorporates three competitive effects that vary both temporally and axially in a GAC column (direct competition for sites, intraparticle pore blockage, and external surface pore blockage). With all three competitive mechanisms accounted for, the model could accurately predict breakthrough profiles for column lengths and durations that were much longer than those used for model parameterization. Model predictions that ignored one or more of the competitive mechanisms showed that each mechanism was important for different regions of the breakthrough curve. The external surface pore-blockage effect was predominant for the prediction of early breakthrough data, whereas direct competition for sites and intraparticle pore blockage were prevalent when predicting higher breakthrough levels and data later in the column run. 22 refs., 10 figs., 2 tabs.

  20. Sympathetic nervous activity decreases during head down bed rest but not during microgravity

    NASA Astrophysics Data System (ADS)

    Christensen, Niels J.; Heer, Martina; Ivanova, Krassimira; Norsk, Peter

    2007-09-01

    Platelet norepinephrine (NE) and epinephrine (E) were measured as indices of long-term changes in sympathoadrenal activity. Ten normal healthy subjects were studied before and during head-down bed rest (HDBR) of 2 weeks duration, as well as during an ambulatory study period of a similar length. Platelet NE and E concentrations were studied in 5 cosmonauts, who participated in three different Soyuz missions to the International Space Station, 2 weeks before launch, within 12 hours after landing following 11 to 12 days of flight and at least 2 weeks after return to earth. Due to the long half-life of NE and E in platelets (approximately 2 days), data obtained early after landing would still reflect the microgravity state. Platelet NE decreased markedly during HDBR (p<0.001). During micro-gravity platelet NE and E increased in 4 of the 5 cosmonauts. Platelet NE and E concentrations expressed in percentage of pre-flight and pre-HDBR values, respectively, were significantly increased during microgravity as compared to HDBR (NE: 153±28% (mean±SEM) vs. 60±6%, p<0.004; E: 293±85% vs. 90±12%, p<0.01). The increase in platelet NE and E during microgravity is most likely due to an increase in sympathoadrenal activity. The reason why sympathoadrenal activity does not decrease to low levels during microgravity as one would expect remains to be elucidated. HDBR cannot be applied to simulate changes in sympathoadrenal activity during microgravity.

  1. Relationships Between sea bed Morphology, Chemosynthetic Biota and Fluid Flow in the Source area of the 1998 Papua New Guinea Tsunami.

    NASA Astrophysics Data System (ADS)

    Tappin, D. R.; McMurtry, G. M.; Matsumoto, T.

    2001-12-01

    The Sissano or Aitape tsunami that struck the north coast of Papua New Guinea (PNG) in the evening of July 17th 1998 left more than 2,000 people dead and 12,000 homeless as three villages were completely destroyed and four more badly damaged. The source of the local tsunami remains controversial and has been postulated as due to seabed dislocation either by thrust or sediment slump, although there is increasing recognition that the latter alternative is most likely. The alternative source mechanisms of the tsunami were addressed during 1999 to 2001 by offshore studies including the acquisition of multibeam bathymetry, sub-bottom profiling, sediment sampling, seabed observation from the JAMSTEC Dolphin 3K Remotely Operated Vehicle and Shinkai 2000 Manned Submersible and seismic profiling. One of the most intriguing discoveries during the offshore surveys was of extant chemosynthetic biological communities, comprising bacterial mats, mussels, and tubeworms. These were found in the amphitheatre region where the source of the tsunami was located. Their presence indicates the active expulsion of sulphide- and methane-rich pore fluids from the sediment. The spatial variation and style of the faunas provides evidence on the mechanisms controlling fluid expulsion, the chemical composition of the fluid, and the levels of fluid flow. There is also undoubtedly a close association between the chemosynthetic faunas, levels of fluid flow and the generation of sediment slumping. We present evidence that shows that the variations in the type and concentration of biota together with variation in the location of active venting and sulphide rich sediments allows discrimination between areas of recently active and less active seabed deformation. We surmise that variations in extant mussel shell size may enable the relative timing of deformation to be elucidated. In conclusion, we propose that detailed mapping of the features and biotas described above supports a slump origin for the

  2. Effects of life stages and feeding regimes on active movement behavior of the tropical bed bug, Cimex hemipterus (Hemiptera: Cimicidae).

    PubMed

    How, Yee-Fatt; Lee, Chow-Yang

    2010-05-01

    This study examined the effects of different life stages (first, second, third, fourth, and five instars; adult females and adult males) and feeding regimes (starved and blood fed) on the active movement activity of the tropical bed bug, Cimex hemipterus (F.), under mixed-stage conditions. We used an extended arena made from Tygon tube coils and observed the movement frequency and movement distance at selected time intervals up to 120 h. The fifth instars and adult males and females showed significantly (P < 0.01) greater movement frequency compared with the other stages. The first and second instars showed limited movement (< 8 m) over the experimental period. Starved bed bugs showed greater movement frequency compared with blood-fed bed bugs, with the exception of adult females. Blood-fed adult females exhibited significantly (P < 0.01) greater movement frequency and distance compared with starved females. Blood-fed females moved up to 42.3 m over 120 h. Regression analysis between movement distance of the fifth instars and adults and the time intervals revealed a positive relationship (r2 = 0.6583; P < 0.01), suggesting that delays in bed bug control efforts will increase the risk of the greater infestation. During bed bug inspection, the presence of only late instars and adults in premises would indicate a new infestation, whereas an established infestation likely would consist of mixed stages.

  3. Acetylcholinesterase activity in the cerebrospinal fluid of dogs with seizures.

    PubMed

    Chai, Orit; Sommer, Adi; Zimmerman, Gabriel; Soreq, Hermona; Friedman, Alon; Bdolah-Abram, Tali; Aroch, Itamar; Shamir, Merav H

    2013-10-01

    Recent studies in animal models have focused on the role of cholinergic elements, mainly acetylcholinesterase (AChE) and the 'readthrough' acetylcholinesterase isoform (AChE-R), in seizures. A prospective double-masked study was conducted to assess the activity of AChE and AChE-R in cerebrospinal fluid (CSF) of 26 dogs post-seizure, 28 dogs with intervertebral disc disease (IVDD) and 16 healthy dogs. AChE was also measured in the serum in the post-seizure and IVDD groups. The results showed no significant differences in CSF AChE among the three groups. AChE-R was not detected in any dog and AChE in the serum was similar between groups. This preliminary study provides new information on AChE and AChE-R in the CSF and sera of dogs following naturally-occurring seizures.

  4. Agriculture--Agricultural Production 1, Seed Bed. Kit No. 6. Instructor's Manual [and] Student Learning Activity Guide.

    ERIC Educational Resources Information Center

    Sloan, Lee

    An instructor's manual and student activity guide on the seed bed are provided in this set of prevocational education materials which focuses on the vocational area of agriculture. (This set of materials is one of ninety-two prevocational education sets arranged around a cluster of seven vocational offerings: agriculture, home economics,…

  5. Fluidized bed steam reformed mineral waste form performance testing to support Hanford Supplemental Low Activity Waste Immobilization Technology Selection

    SciTech Connect

    Jantzen, C. M.; Pierce, E. M.; Bannochie, C. J.; Burket, P. R.; Cozzi, A. D.; Crawford, C. L.; Daniel, W. E.; Fox, K. M.; Herman, C. C.; Miller, D. H.; Missimer, D. M.; Nash, C. A.; Williams, M. F.; Brown, C. F.; Qafoku, N. P.; Neeway, J. J.; Valenta, M. M.; Gill, G. A.; Swanberg, D. J.; Robbins, R. A.; Thompson, L. E.

    2015-10-01

    This report describes the benchscale testing with simulant and radioactive Hanford Tank Blends, mineral product characterization and testing, and monolith testing and characterization. These projects were funded by DOE EM-31 Technology Development & Deployment (TDD) Program Technical Task Plan WP-5.2.1-2010-001 and are entitled “Fluidized Bed Steam Reformer Low-Level Waste Form Qualification”, Inter-Entity Work Order (IEWO) M0SRV00054 with Washington River Protection Solutions (WRPS) entitled “Fluidized Bed Steam Reforming Treatability Studies Using Savannah River Site (SRS) Low Activity Waste and Hanford Low Activity Waste Tank Samples”, and IEWO M0SRV00080, “Fluidized Bed Steam Reforming Waste Form Qualification Testing Using SRS Low Activity Waste and Hanford Low Activity Waste Tank Samples”. This was a multi-organizational program that included Savannah River National Laboratory (SRNL), THOR® Treatment Technologies (TTT), Pacific Northwest National Laboratory (PNNL), Oak Ridge National Laboratory (ORNL), Office of River Protection (ORP), and Washington River Protection Solutions (WRPS). The SRNL testing of the non-radioactive pilot-scale Fluidized Bed Steam Reformer (FBSR) products made by TTT, subsequent SRNL monolith formulation and testing and studies of these products, and SRNL Waste Treatment Plant Secondary Waste (WTP-SW) radioactive campaign were funded by DOE Advanced Remediation Technologies (ART) Phase 2 Project in connection with a Work-For-Others (WFO) between SRNL and TTT.

  6. Geochemical constraints on the diversity and activity of H2 -oxidizing microorganisms in diffuse hydrothermal fluids from a basalt- and an ultramafic-hosted vent.

    PubMed

    Perner, Mirjam; Petersen, Jillian M; Zielinski, Frank; Gennerich, Hans-Hermann; Seifert, Richard

    2010-10-01

    Mixing processes of reduced hydrothermal fluids with oxygenated seawater and fluid-rock reactions contribute to the chemical signatures of diffuse venting and likely determine the geochemical constraints on microbial life. We examined the influence of fluid chemistry on microbial diversity and activity by sampling diffuse fluids emanating through mussel beds at two contrasting hydrothermal vents. The H(2) concentration was very low at the basalt-hosted Clueless site, and mixing models suggest O(2) availability throughout much of the habitat. In contrast, effluents from the ultramafic-hosted Quest site were considerably enriched in H(2) , while O(2) is likely limited to the mussel layer. Only two different hydrogenase genes were identified in clone libraries from the H(2) -poor Clueless fluids, but these fluids exhibited the highest H(2) uptake rates in H(2) -spiked incubations (oxic conditions, at 18 °C). In contrast, a phylogenetically diverse H(2) -oxidizing potential was associated with distinct thermal conditions in the H(2) -rich Quest fluids, but under oxic conditions, H(2) uptake rates were extremely low. Significant stimulation of CO(2) fixation rates by H(2) addition was solely illustrated in Quest incubations (P-value <0.02), but only in conjunction with anoxic conditions (at 18 °C). We conclude that the factors contributing toward differences in the diversity and activity of H(2) oxidizers at these sites include H(2) and O(2) availability.

  7. Increased Brain Activation for Dual Tasking with 70-Days Head-Down Bed Rest

    PubMed Central

    Yuan, Peng; Koppelmans, Vincent; Reuter-Lorenz, Patricia A.; De Dios, Yiri E.; Gadd, Nichole E.; Wood, Scott J.; Riascos, Roy; Kofman, Igor S.; Bloomberg, Jacob J.; Mulavara, Ajitkumar P.; Seidler, Rachael D.

    2016-01-01

    Head-down tilt bed rest (HDBR) has been used as a spaceflight analog to simulate the effects of microgravity exposure on human physiology, sensorimotor function, and cognition on Earth. Previous studies have reported that concurrent performance of motor and cognitive tasks can be impaired during space missions. Understanding the consequences of HDBR for neural control of dual tasking may possibly provide insight into neural efficiency during spaceflight. In the current study, we evaluated how dual task performance and the underlying brain activation changed as a function of HDBR. Eighteen healthy men participated in this study. They remained continuously in the 6° head-down tilt position for 70 days. Functional MRI for bimanual finger tapping was acquired during both single task and dual task conditions, and repeated at 7 time points pre-, during- and post-HDBR. Another 12 healthy males participated as controls who did not undergo HDBR. A widely distributed network involving the frontal, parietal, cingulate, temporal, and occipital cortices exhibited increased activation for dual tasking and increased activation differences between dual and single task conditions during HDBR relative to pre- or post-HDBR. This HDBR-related brain activation increase for dual tasking implies that more neurocognitive control is needed for dual task execution during HDBR compared to pre- and post-HDBR. We observed a positive correlation between pre-to-post HDBR changes in dual-task cost of reaction time and pre-to-post HDBR change in dual-task cost of brain activation in several cerebral and cerebellar regions. These findings could be predictive of changes in dual task processing during spaceflight. PMID:27601982

  8. Sublethal Effects of ActiveGuard Exposure on Feeding Behavior and Fecundity of the Bed Bug (Hemiptera: Cimicidae).

    PubMed

    Jones, Susan C; Bryant, Joshua L; Sivakoff, Frances S

    2015-05-01

    Sublethal exposure to pesticides can alter insect behavior with potential for population-level consequences. We investigated sublethal effects of ActiveGuard, a permethrin-impregnated fabric, on feeding behavior and fecundity of bed bugs (Cimex lectularius L.) from five populations that ranged from susceptible to highly pyrethroid resistant. After exposure to ActiveGuard fabric or untreated fabric for 1 or 10 min, adult virgin female bed bugs were individually observed when offered a blood meal to determine feeding attempts and weight gain. Because bed bug feeding behavior is tightly coupled with its fecundity, all females were then mated, and the number of eggs laid and egg hatch rate were used as fecundity measures. We observed that pyrethroid-resistant and -susceptible bugs were not significantly different for all feeding and fecundity parameters. Bed bugs exposed to ActiveGuard for 10 min were significantly less likely to attempt to feed or successfully feed, and their average blood meal size was significantly smaller compared with individuals in all other groups. Independent of whether or not feeding occurred, females exposed to ActiveGuard for 10 min were significantly more likely to lay no eggs. Only a single female exposed to ActiveGuard for 10 min laid any eggs. Among the other fabric treatment-exposure time groups, there were no observable differences in egg numbers or hatch rates. Brief exposure of 10 min to ActiveGuard fabric appeared to decrease feeding and fecundity of pyrethroid-resistant and susceptible bed bugs, suggesting the potentially important role of sublethal exposure for the control of this ectoparasitic insect.

  9. Bed Bugs

    EPA Pesticide Factsheets

    Prevent, identify, and treat bed bug infestations using EPA’s step-by-step guides, based on IPM principles. Find pesticides approved for bed bug control, check out the information clearinghouse, and dispel bed bug myths.

  10. 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.

  11. Active magnetic regenerator method and apparatus

    DOEpatents

    DeGregoria, Anthony J.; Zimm, Carl B.; Janda, Dennis J.; Lubasz, Richard A.; Jastrab, Alexander G.; Johnson, Joseph W.; Ludeman, Evan M.

    1993-01-01

    In an active magnetic regenerator apparatus having a regenerator bed of material exhibiting the magnetocaloric effect, flow of heat transfer fluid through the bed is unbalanced, so that more fluid flows through the bed from the hot side of the bed to the cold side than from the cold side to the hot side. The excess heat transfer fluid is diverted back to the hot side of the bed. The diverted fluid may be passed through a heat exchanger to draw heat from a fluid to be cooled. The apparatus may be operated at cryogenic temperatures, and the heat transfer fluid may be helium gas and the fluid to be cooled may be hydrogen gas, which is liquified by the device. The apparatus can be formed in multiple stages to allow a greater span of cooling temperatures than a single stage, and each stage may be comprised of two bed parts. Where two bed parts are employed in each stage, a portion of the fluid passing from the hot side to the cold side of a first bed part which does not have a magnetic field applied thereto is diverted back to the cold side of the other bed part in the stage, where it is passed through to the hot side. The remainder of the fluid from the cold side of the bed part of the first stage is passed to the hot side of the bed part of the second stage.

  12. Influence of binder properties, method of addition, powder type and operating conditions on fluid-bed melt granulation and resulting tablet properties.

    PubMed

    Abberger, T

    2001-12-01

    The aim of the study was to investigate melt granulation in a laboratory scale fluid-bed granulator with respect to granule growth, granule properties and resulting tablet properties. The parameters investigated were method of addition of PEG (spray-on or addition as flakes), binder concentration, PEG type (3000, 4000 and 6000, sprayed-on), size (PEG 4000, added as three different sized flakes), powder type (two different sized lactose types and corn starch) and operating conditions (volume air flow and heating temperature). Addition of binder as flakes led to layering as a growth mechanism when the size of the flakes was high. Coalescence occurred when the size was low. Coalescence also occurred when spraying was the method of addition. Due to the greater viscosity of the PEG 6000 melt it produced bigger granules than 3000 or 4000. The influence of volume air flow was moderate and the influence of heating temperature in the range of 70-90 degrees C was very low with both methods of addition. The disintegration time of tablets from granules where PEG was added as flakes was shorter than from granules where PEG was sprayed-on. The latter method of binder addition led to tablets which did not disintegrate but eroded. This was apparently caused by formation of a binder matrix, which could not be destroyed by the disintegrant.

  13. Removal of alkali vapors by a fixed granular-bed sorber using activated bauxite as a sorbent

    SciTech Connect

    Lee, S.H.D.; Henry, R.F.; Myles, K.M.

    1985-03-01

    Studies have been conducted to develop a fixed granular-bed sorber for the removal of alkali vapors in a pressurized fluidized-bed combustion (PFBC) combinedcycle system. A laboratory-scale pressurized alkalivapor sorption test unit was used to characterize activated bauxite, the most effective sorbent identified earlier, for its alkali vapor sorption capability in a gas stream with temperature (less than or equal to900/sup 0/C), pressure (10 atm absolute), and composition closely simulating the actual PFBC flue gas. A scale-up of laboratory tests is being conducted in a 15.2-cm-dia (6-in.-dia) PFBC system to demonstrate the granular-bed sorber concept. The NaCl-vapor sorption chemistry of activated bauxite is described. The extent of alkalivapor evolution from the activated bauxite bed itself is discussed, along with an evaluation of the significance of its alkali vapor contribution to a downstream gas turbine. Details of the design of a high-temperature/high-pressure alkali sorber system for the demonstration of the sorber are presented.

  14. Removal of alkali vapors by a fixed granular-bed sorber using activated bauxite as a sorbent

    SciTech Connect

    Lee, S.H.D.; Henry, R.F.; Myles, K.M.

    1985-01-01

    Studies have been conducted to develop a fixed granular-bed sorber for the removal of alkali vapors in a pressurized fluidized-bed combustion (PFBC) combined-cycle system. A laboratory-scale pressurized alkali vapor sorption test unit was used to characterize activated bauxite, the most effective sorbent identified earlier, for its alkali vapor sorption capability in a gas stream with temperature (less than or equal to 900/sup 0/C), pressure (10 atm absolute), and composition closely simulating the actual PFBC flue gas. A scale-up of laboratory tests is being conducted in a 15.2-cm-dia (6-in.-dia) PFBC system to demonstrate the granular-bed sorber concept. The NaCl-vapor sorption chemistry of activated bauxite is described. The extent of alkali-vapor evolution from the activated bauxite bed itself is discussed, along with an evaluation of the significance of its alkali vapor contribution to a downstream gas turbine. Details of the design of a high-temperature/high-pressure alkali sorber system for the demonstration of the sorber are presented. 15 references, 6 figures, 3 tables.

  15. Diagnostic value of creatine kinase activity in canine cerebrospinal fluid

    PubMed Central

    Ferreira, Alexandra

    2016-01-01

    This study aimed to determine whether creatine kinase (CK) activity in cerebrospinal fluid (CSF) has diagnostic value for various groups of neurological conditions or for different anatomical areas of the nervous system (NS). The age, breed, results of CSF analysis, and diagnosis of 578 canine patients presenting with various neurological conditions between January 2009 and February 2015 were retrospectively collected. The cases were divided according to anatomical areas of the nervous system, i.e., brain, spinal cord, and peripheral nervous system, and into groups according to the nature of the condition diagnosed: vascular, immune/inflammatory/infectious, traumatic, toxic, anomalous, metabolic, idiopathic, neoplastic, and degenerative. Statistical analysis showed that CSF-CK alone cannot be used as a diagnostic tool and that total proteins in the CSF and red blood cells (RBCs) do not have a significant relationship with the CSF-CK activity. CSF-CK did not have a diagnostic value for different disease groups or anatomical areas of the nervous system. PMID:27708448

  16. Minimal continuum theories of structure formation in dense active fluids

    NASA Astrophysics Data System (ADS)

    Dunkel, Jörn; Heidenreich, Sebastian; Bär, Markus; Goldstein, Raymond E.

    2013-04-01

    Self-sustained dynamical phases of living matter can exhibit remarkable similarities over a wide range of scales, from mesoscopic vortex structures in microbial suspensions and motility assays of biopolymers to turbulent large-scale instabilities in flocks of birds or schools of fish. Here, we argue that, in many cases, the phenomenology of such active states can be efficiently described in terms of fourth- and higher-order partial differential equations. Structural transitions in these models can be interpreted as Landau-type kinematic transitions in Fourier (wavenumber) space, suggesting that microscopically different biological systems can share universal long-wavelength features. This general idea is illustrated through numerical simulations for two classes of continuum models for incompressible active fluids: a Swift-Hohenberg-type scalar field theory, and a minimal vector model that extends the classical Toner-Tu theory and appears to be a promising candidate for the quantitative description of dense bacterial suspensions. We discuss how microscopic symmetry-breaking mechanisms can enter macroscopic continuum descriptions of collective microbial motion near surfaces, and conclude by outlining future applications.

  17. Efficient removal of antibiotics in a fluidized bed reactor by facile fabricated magnetic powdered activated carbon.

    PubMed

    Ma, Jianqing; Yang, Qunfeng; Xu, Dongmei; Zeng, Xiaomei; Wen, Yuezhong; Liu, Weiping

    2017-02-01

    Powdered activated carbons (PACs) with micrometer size are showing great potential for enabling and improving technologies in water treatment. The critical problem in achieving practical application of PAC involves simple, effective fabrication of magnetic PAC and the design of a feasible reactor that can remove pollutants and recover the adsorbent efficiently. Herein, we show that such materials can be fabricated by the combination of PAC and magnetic Fe3O4 with chitosan-Fe hydrogel through a simple co-precipitation method. According to the characterization results, CS-Fe/Fe3O4/PAC with different micrometers in size exhibited excellent magnetic properties. The adsorption of tetracycline was fast and efficient, and 99.9% removal was achieved in 30 min. It also possesses good usability and stability to co-existing ions, organics, and different pH values due to its dispersive interaction nature. Finally, the prepared CS-Fe/Fe3O4/PAC also performed well in the fluidized bed reactor with electromagnetic separation function. It could be easily separated by applying a magnetic field and was effectively in situ regenerated, indicating a potential of practical application for the removal of pollutants from water.

  18. Physical activity, subjective sleep quality and time in bed do not vary by moon phase in German adolescents.

    PubMed

    Smith, Maia P; Standl, Marie; Schulz, Holger; Heinrich, Joachim

    2016-12-08

    Lunar periodicity in human biology and behaviour, particularly sleep, has been reported. However, estimated relationships vary in direction (more or less sleep with full moon) if they exist at all, and studies tend to be so small that there is potential for confounding by weekly or monthly cycles. Lunar variation in physical activity has been posited as a driver of this relationship, but is likewise not well studied. We explore the association between lunar cycle, sleep and physical activity in a population-based sample of 1411 Germans age 14-17 years (46% male). Physical activity (daily minutes moderate-to-vigorous activity) was objectively assessed by accelerometry for a total of 8832 days between 2011 and 2014. At the same time, time in bed (h) and subjective sleep quality (1-6) were diaried each morning. In models corrected for confounding, we found that lunar phase was not significantly associated with physical activity, subjective sleep quality or time in bed in either sex, regardless of season. Observed relationships varied randomly in direction between models, suggesting artefact. Thus, this large, objectively-measured and well-controlled population of adolescents displayed no lunar periodicity in objective physical activity, subjective sleep quality or time in bed.

  19. EMERGING TECHNOLOGY BULLETIN: SPOUTED BED REACTOR

    EPA Science Inventory

    The Spouted Bed Reactor (SBR) technology utilizes the unique attributes of the "spouting " fluidization regime, which can provide heat transfer rates comparable to traditional fluid beds, while providing robust circulation of highly heterogeneous solids, concurrent with very agg...

  20. Bed bugs.

    PubMed

    Foulke, Galen T; Anderson, Bryan E

    2014-09-01

    The term bed bug is applied to 2 species of genus Cimex: lectularius describes the common or temperate bed bug, and hemipterus its tropical cousin. Cimex lectularius is aptly named; its genus and species derive from the Latin words for bug and bed, respectively. Though the tiny pest is receiving increased public attention and scrutiny, the bed bug is hardly a new problem.

  1. Coupling of solid-phase microextraction continuous bed (monolithic) capillaries with capillary zone electrophoresis for direct analysis of drugs in biological fluids.

    PubMed

    Jarmalaviciene, Reda; Szumski, Michał; Kornysova, Olga; Kłodzińska, Ewa; Westerlund, Douglas; Krawczyk, Stanislas; Mickevicius, Donatas; Buszewski, Bogusław; Maruska, Audrius

    2008-04-01

    Hyperlink robust biocompatible solid-phase microextraction (SPME) devices were prepared using continuous bed (monolithic) restricted-access media (RAM) as the SPME capillary insert. The RAM-based SPME approach was able to simultaneously separate proteins from a biological sample, while directly extracting the active components of caffeine, paracetamol and acetylsalicylic acid from the drug NeoCitramonum. The devices were interfaced with a CZE system and fully automated analysis for sample preconcentration, desorption, separation and quantification of analytes was evaluated. Comparative study of in-line coupled SPME-CZE using RAM and RP capillary inserts was carried out. Using an SPME (RAM) insert, the calculated caffeine, paracetamol and acetylsalicylic acid LODs in a bovine plasma sample were 0.3, 0.8 and 1.9 ng/mL, respectively.

  2. Heterogeneous decomposition of silane in a fixed bed reactor

    NASA Technical Reports Server (NTRS)

    Iya, S. K.; Flagella, R. N.; Dipaolo, F. S.

    1982-01-01

    Heterogeneous decomposition of silane in a fluidized bed offers an attractive route for the low-cost production of silicon for photovoltaic application. To obtain design data for a fluid bed silane pyrolysis reactor, deposition experiments were conducted in a small-scale fixed bed apparatus. Data on the decomposition mode, plating rate, and deposition morphology were obtained in the temperature range 600-900 C. Conditions favorable for heterogeneous decomposition with good deposition morphology were identified. The kinetic rate data showed the reaction to be first order with an activation energy of 38.8 kcal/mol, which agrees well with work done by others. The results are promising for the development of an economically attractive fluid bed process.

  3. Heterogeneous decomposition of silane in a fixed bed reactor

    NASA Technical Reports Server (NTRS)

    Iya, S. K.; Flagella, R. N.; Dipaolo, F. S.

    1981-01-01

    Heterogeneous decomposition of silane in a fluidized bed offers an attractive route for the low-cost production of silicon for photovoltaic application. To obtain design data for a fluid bed silane pyrolysis reactor, deposition experiments were conducted in a small-scale fixed bed apparatus. Data on the decomposition mode, plating rate, and deposition morphology were obtained in the temperature range 600 900 C. Conditions favorable for heterogenous decomposition with good deposition morphology were identified. The kinetic rate data showed the reaction to be first order with an activation energy of 38.8 kcal/mole, which agrees well with work done by others. The results are promising for the development of an economically attractive fluid bed process.

  4. Nitrous oxide from moving bed based integrated fixed film activated sludge membrane bioreactors.

    PubMed

    Mannina, Giorgio; Capodici, Marco; Cosenza, Alida; Di Trapani, Daniele; Laudicina, Vito Armando; Ødegaard, Hallvard

    2017-02-01

    The present paper reports the results of a nitrous oxide (N2O) production investigation in a moving bed based integrated fixed film activated sludge (IFAS) membrane bioreactor (MBR) pilot plant designed in accordance with the University of Cape Town layout for biological phosphorous removal. Gaseous and liquid samples were collected in order to measure the gaseous as well as the dissolved concentration of N2O. Furthermore, the gas flow rate from each reactor was measured and the gas flux was estimated. The results confirmed that the anoxic reactor represents the main source of nitrous oxide production. A significant production of N2O was, however, also found in the anaerobic reactor, thus indicating a probable occurrence of the denitrifying phosphate accumulating organism activity. The highest N2O fluxes were emitted from the aerated reactors (3.09 g N2ON m(-2) h(-1) and 9.87 g N2ON m(-2) h(-1), aerobic and MBR tank, respectively). The emission factor highlighted that only 1% of the total treated nitrogen was emitted from the pilot plant. Furthermore, the measured N2O concentrations in the permeate flow were comparable with other reactors. Nitrous oxide mass balances outlined a moderate production also in the MBR reactor despite the low hydraulic retention time. On the other hand, the mass balance showed that in the aerobic reactor a constant consumption of nitrous oxide (up to almost 15 mg N2O h(-1)) took place, due to the high amount of stripped gas.

  5. Active microchannel fluid processing unit and method of making

    DOEpatents

    Bennett, Wendy D [Kennewick, WA; Martin, Peter M [Kennewick, WA; Matson, Dean W [Kennewick, WA; Roberts, Gary L [West Richland, WA; Stewart, Donald C [Richland, WA; Tonkovich, Annalee Y [Pasco, WA; Zilka, Jennifer L [Pasco, WA; Schmitt, Stephen C [Dublin, OH; Werner, Timothy M [Columbus, OH

    2002-12-10

    The present invention is an active microchannel fluid processing unit and method of making, both relying on having (a) at least one inner thin sheet; (b) at least one outer thin sheet; (c) defining at least one first sub-assembly for performing at least one first unit operation by stacking a first of the at least one inner thin sheet in alternating contact with a first of the at least one outer thin sheet into a first stack and placing an end block on the at least one inner thin sheet, the at least one first sub-assembly having at least a first inlet and a first outlet; and (d) defining at least one second sub-assembly for performing at least one second unit operation either as a second flow path within the first stack or by stacking a second of the at least one inner thin sheet in alternating contact with second of the at least one outer thin sheet as a second stack, the at least one second sub-assembly having at least a second inlet and a second outlet.

  6. Active microchannel fluid processing unit and method of making

    DOEpatents

    Bennett, Wendy D [Kennewick, WA; Martin, Peter M [Kennewick, WA; Matson, Dean W [Kennewick, WA; Roberts, Gary L [West Richland, WA; Stewart, Donald C [Richland, WA; Tonkovich, Annalee Y [Pasco, WA; Zilka, Jennifer L [Pasco, WA; Schmitt, Stephen C [Dublin, OH; Werner, Timothy M [Columbus, OH

    2001-01-01

    The present invention is an active microchannel fluid processing unit and method of making, both relying on having (a) at least one inner thin sheet; (b) at least one outer thin sheet; (c) defining at least one first sub-assembly for performing at least one first unit operation by stacking a first of the at least one inner thin sheet in alternating contact with a first of the at least one outer thin sheet into a first stack and placing an end block on the at least one inner thin sheet, the at least one first sub-assembly having at least a first inlet and a first outlet; and (d) defining at least one second sub-assembly for performing at least one second unit operation either as a second flow path within the first stack or by stacking a second of the at least one inner thin sheet in alternating contact with second of the at least one outer thin sheet as a second stack, the at least one second sub-assembly having at least a second inlet and a second outlet.

  7. Active fluid mixing with magnetic microactuators for capture of salmonella

    NASA Astrophysics Data System (ADS)

    Hanasoge, S.; Owen, D.; Ballard, M.; Mills, Z.; Xu, J.; Erickson, M.; Hesketh, P. J.; Alexeev, A.

    2016-05-01

    Detection of low concentrations of bacteria in food samples is a challenging process. Key to this process is the separation of the target from the food matrix. We demonstrate magnetic beads and magnetic micro-cilia based microfluidic mixing and capture, which are particularly useful for pre-concentrating the target. The first method we demonstrate makes use of magnetic microbeads held on to NiFe discs on the surface of the substrate. These beads are rotated around the magnetic discs by rotating the external magnetic field. The second method we demonstrate shows the use of cilia which extends into the fluid and is manipulated by a rotating external field. Magnetic micro-features were fabricated by evaporating NiFe alloy at room temperature, on to patterned photoresist. The high magnetic permeability of NiFe allows for maximum magnetic force on the features. The magnetic features were actuated using an external rotating magnet up to frequencies of 50Hz. We demonstrate active mixing produced by the microbeads and the cilia in a microchannel. Also, we demonstrate the capture of target species in a sample using microbeads.

  8. Locomotion in fluids using shape-changing active materials.

    NASA Astrophysics Data System (ADS)

    Shelley, Michael; Palffy-Muhoray, Peter; Comacho-Lopez, Miguel; Malacarne, Luis; Finkelmann, Heino

    2004-11-01

    Liquid crystal elastomers (LCEs) are rubbers made up of liquid crystal molecules, and can exhibit large and fast shape deformations when exposed to external fields. We discuss recent experiments in which an LCE sample floating on water is illuminated by a laser. Upon illumination the sample simultaneously changes both its shape and position, ``swimming'' away from the laser light. In this system, energy from the light is used to effect momentum transfer between the LCE body and the surrounding fluid. We discuss the origins of the shape change, the resulting LCE/fluid interaction, and the modeling of such fluid/materials systems.

  9. Aqueous phase adsorption of cephalexin by walnut shell-based activated carbon: A fixed-bed column study

    NASA Astrophysics Data System (ADS)

    Nazari, Ghadir; Abolghasemi, Hossein; Esmaieli, Mohamad; Sadeghi Pouya, Ehsan

    2016-07-01

    The walnut shell was used as a low cost adsorbent to produce activated carbon (AC) for the removal of cephalexin (CFX) from aqueous solution. A fixed-bed column adsorption was carried out using the walnut shell AC. The effect of various parameters like bed height (1.5, 2 and 2.5 cm), flow rate (4.5, 6 and 7.5 mL/min) and initial CFX concentration (50, 100 and 150 mg/L) on the breakthrough characteristics of the adsorption system was investigated at optimum pH 6.5. The highest bed capacity of 211.78 mg/g was obtained using 100 mg/L inlet drug concentration, 2 cm bed height and 4.5 mL/min flow rate. Three kinetic models, namely Adam's-Bohart, Thomas and Yoon-Nelson were applied for analysis of experimental data. The Thomas and Yoon-Nelson models were appropriate for walnut shell AC column design under various conditions. The experimental adsorption capacity values were fitted to the Bangham and intra-particle diffusion models in order to propose adsorption mechanisms. The effect of temperature on the degradation of CFX was also studied.

  10. Mean 24-hours sympathetic nervous system activity decreases during head-down tilted bed rest but not during microgravity

    NASA Astrophysics Data System (ADS)

    Christensen, Nj; Heer, M.; Ivanova, K.; Norsk, P.

    Sympathetic nervous system activity is closely related to gravitational stress in ground based experiments. Thus a high activity is present in the standing-up position and a very low activity is observed during acute head-out water immersion. Adjustments in sympathetic activity are necessary to maintain a constant blood pressure during variations in venous return. Head-down tilted bed rest is applied as a model to simulate changes observed during microgravity. The aim of the present study was to test the hypothesis that mean 24-hours sympathetic activity was low and similar during space flight and in ground based observation obtained during long-term head-down tilted bed rest. Forearm venous plasma noradrenaline was measured by a radioenzymatic technique as an index of muscle sympathetic activity and thrombocyte noradrenaline and adrenaline were measured as indices of mean 24-hours sympathoadrenal activity. Previous results have indicated that thrombocyte noradrenaline level has a half-time of 2 days. Thus to reflect sympathetic activity during a specific experiment the study period must last for at least 6 days and a sample must be obtained within 12 hours after the experiment has ended. Ten normal healthy subjects were studied before and during a 14 days head-down tilted bed rest as well as during an ambulatory study period of a similar length. The whole experiment was repeated while the subjects were on a low calorie diet. Thrombocyte noradrenaline levels were studied in 4 cosmonauts before and within 12 hours after landing after more than 7 days in flight. Thrombocyte noradrenaline decreased markedly during the head-down tilted bed rest (p<0.001), whereas there were no significant changes in the ambulatory study. Plasma noradrenaline decreased in the adaptation period but not during the intervention. During microgravity thrombocyte noradrenaline increased in four cosmonauts and the percentage changes were significantly different in cosmonauts and in subjects

  11. Batch Tests To Determine Activity Distribution and Kinetic Parameters for Acetate Utilization in Expanded-Bed Anaerobic Reactors

    PubMed Central

    Fox, Peter; Suidan, Makram T.

    1990-01-01

    Batch tests to measure maximum acetate utilization rates were used to determine the distribution of acetate utilizers in expanded-bed sand and expanded-bed granular activated carbon (GAC) reactors. The reactors were fed a mixture of acetate and 3-ethylphenol, and they contained the same predominant aceticlastic methanogen, Methanothrix sp. Batch tests were performed both on the entire reactor contents and with media removed from the reactors. Results indicated that activity was evenly distributed within the GAC reactors, whereas in the sand reactor a sludge blanket on top of the sand bed contained approximately 50% of the activity. The Monod half-velocity constant (Ks) for the acetate-utilizing methanogens in two expanded-bed GAC reactors was searched for by combining steady-state results with batch test data. All parameters necessary to develop a model with Monod kinetics were experimentally determined except for Ks. However, Ks was a function of the effluent 3-ethylphenol concentration, and batch test results demonstrated that maximum acetate utilization rates were not a function of the effluent 3-ethylphenol concentration. Addition of a competitive inhibition term into the Monod expression predicted the dependence of Ks on the effluent 3-ethylphenol concentration. A two-parameter search determined a Ks of 8.99 mg of acetate per liter and a Ki of 2.41 mg of 3-ethylphenol per liter. Model predictions were in agreement with experimental observations for all effluent 3-ethylphenol concentrations. Batch tests measured the activity for a specific substrate and determined the distribution of activity in the reactor. The use of steady-state data in conjunction with batch test results reduced the number of unknown kinetic parameters and thereby reduced the uncertainty in the results and the assumptions made. PMID:16348175

  12. [Research activities in applied mathematics, fluid mechanics, and computer science

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This report summarizes research conducted at the Institute for Computer Applications in Science and Engineering in applied mathematics, fluid mechanics, and computer science during the period April 1, 1995 through September 30, 1995.

  13. Adsorption behavior of pesticide methomyl on activated carbon in a high gravity rotating packed bed reactor.

    PubMed

    Chang, Chiung-Fen; Lee, Shu-Chi

    2012-06-01

    High gravity rotating packed bed (HGRPB) reactor possesses the property of high mass transfer rate, which is expected to promote the adsorption rate for the process. In this study, HGRPB has been applied on adsorption removal of methomyl from solution, adopting the adsorbent of activated carbon F400. The influence of operating parameters of HGRPB on mass transfer such as the rotating speed (N(R)), the flow rate of solution (F(L)) and initial concentration of methomyl (C(b0)) were examined. The traditionally internal mass transfer models combined with Freundlich isotherm were used to predict the surface and effective diffusion coefficients. In addition, the results have also been compared with those obtained from the traditional basket stirred batch reactor (BBR). The results showed that the larger values of N(R) and F(L) enhanced the effective intraparticle diffusion and provided more accessible adsorption sites so as to result in lower equilibrium concentration in HGRPB system when compared to SBR system. The results of adsorption kinetics demonstrated that surface and effective diffusions were both significantly greater in HGRPB system instead of BBR system. Furthermore, the values of Bi(S) also manifested less internal mass transfer resistance in HGRPB system. The contribution ratio (R(F)) of the surface to pore diffusion mass transport showed that the larger contribution resulted from the surface diffusion in HGRPB system. Therefore, the results reasonably led to the conclusion that when the HGRPB system applied on the adsorption of methomyl on F400, the lower equilibrium concentration and faster internal mass transfer can be obtained so as to highly possess great potential to match the gradually stricter environmental standard.

  14. Corn stalks char from fast pyrolysis as precursor material for preparation of activated carbon in fluidized bed reactor.

    PubMed

    Wang, Zhiqi; Wu, Jingli; He, Tao; Wu, Jinhu

    2014-09-01

    Corn stalks char from fast pyrolysis was activated by physical and chemical activation process in a fluidized bed reactor. The structure and morphology of the carbons were characterized by N2 adsorption and SEM. Effects of activation time and activation agents on the structure of activation carbon were investigated. The physically activated carbons with CO2 have BET specific surface area up to 880 m(2)/g, and exhibit microporous structure. The chemically activated carbons with H3PO4 have BET specific surface area up to 600 m(2)/g, and exhibit mesoporous structure. The surface morphology shows that physically activated carbons exhibit fibrous like structure in nature with long ridges, resembling parallel lines. Whereas chemically activated carbons have cross-interconnected smooth open pores without the fibrous like structure.

  15. Predicting apparent Sherwood numbers for fluidized beds

    SciTech Connect

    Groenewold, H.; Tsotsas, E.

    1999-09-01

    Mass transfer data of bubbling fluidized beds have been reevaluated with a new model which is completely predictive. The model is based on a two-phase approach with active bypass, formally plug flow for the suspension gas and a consideration of backmixing in the main kinetic coefficient, i.e. in the apparent particle-to-fluid Sherwood number. A good agreement with experimental results of various authors with a broad range of Reynolds numbers and particle diameters is demonstrated.

  16. Enhanced removal of sulfonamide antibiotics by KOH-activated anthracite coal: Batch and fixed-bed studies.

    PubMed

    Zuo, Linzi; Ai, Jing; Fu, Heyun; Chen, Wei; Zheng, Shourong; Xu, Zhaoyi; Zhu, Dongqiang

    2016-04-01

    The presence of sulfonamide antibiotics in aquatic environments poses potential risks to human health and ecosystems. In the present study, a highly porous activated carbon was prepared by KOH activation of an anthracite coal (Anth-KOH), and its adsorption properties toward two sulfonamides (sulfamethoxazole and sulfapyridine) and three smaller-sized monoaromatics (phenol, 4-nitrophenol and 1,3-dinitrobenzene) were examined in both batch and fixed-bed adsorption experiments to probe the interplay between adsorbate molecular size and adsorbent pore structure. A commercial powder microporous activated carbon (PAC) and a commercial mesoporous carbon (CMK-3) possessing distinct pore properties were included as comparative adsorbents. Among the three adsorbents Anth-KOH exhibited the largest adsorption capacities for all test adsorbates (especially the two sulfonamides) in both batch mode and fixed-bed mode. After being normalized by the adsorbent surface area, the batch adsorption isotherms of sulfonamides on PAC and Anth-KOH were displaced upward relative to the isotherms on CMK-3, likely due to the micropore-filling effect facilitated by the microporosity of adsorbents. In the fixed-bed mode, the surface area-normalized adsorption capacities of Anth-KOH for sulfonamides were close to that of CMK-3, and higher than that of PAC. The irregular, closed micropores of PAC might impede the diffusion of the relatively large-sized sulfonamide molecules and in turn led to lowered fixed-bed adsorption capacities. The overall superior adsorption of sulfonamides on Anth-KOH can be attributed to its large specific surface area (2514 m(2)/g), high pore volume (1.23 cm(3)/g) and large micropore sizes (centered at 2.0 nm). These findings imply that KOH-activated anthracite coal is a promising adsorbent for the removal of sulfonamide antibiotics from aqueous solution.

  17. Microbial life in cold, hydrologically active oceanic crustal fluids

    NASA Astrophysics Data System (ADS)

    Meyer, J. L.; Jaekel, U.; Girguis, P. R.; Glazer, B. T.; Huber, J. A.

    2012-12-01

    It is estimated that at least half of Earth's microbial biomass is found in the deep subsurface, yet very little is known about the diversity and functional roles of these microbial communities due to the limited accessibility of subseafloor samples. Ocean crustal fluids, which may have a profound impact on global nutrient cycles given the large volumes of water moving through the crustal aquifer, are particularly difficult to sample. Access to uncontaminated ocean crustal fluids is possible with CORK (Circulation Obviation Retrofit Kit) observatories, installed through the Integrated Ocean Drilling Program (IODP). Here we present the first microbiological characterization of the formation fluids from cold, oxygenated igneous crust at North Pond on the western flank of the Mid Atlantic Ridge. Fluids were collected from two CORKs installed at IODP boreholes 1382A and 1383C and include fluids from three different depth horizons within oceanic crust. Collection of borehole fluids was monitored in situ using an oxygen optode and solid-state voltammetric electrodes. In addition, discrete samples were analyzed on deck using a comparable lab-based system as well as a membrane-inlet mass spectrometer to quantify all dissolved volatiles up to 200 daltons. The instruments were operated in parallel and both in situ and shipboard geochemical measurements point to a highly oxidized fluid, revealing an apparent slight depletion of oxygen in subsurface fluids (~215μM) relative to bottom seawater (~245μM). We were unable to detect reduced hydrocarbons, e.g. methane. Cell counts indicated the presence of roughly 2 x 10^4 cells per ml in all fluid samples, and DNA was extracted and amplified for the identification of both bacterial and archaeal community members. The utilization of ammonia, nitrate, dissolved inorganic carbon, and acetate was measured using stable isotopes, and oxygen consumption was monitored to provide an estimate of the rate of respiration per cell per day

  18. Fast fluidized bed steam generator

    DOEpatents

    Bryers, Richard W.; Taylor, Thomas E.

    1980-01-01

    A steam generator in which a high-velocity, combustion-supporting gas is passed through a bed of particulate material to provide a fluidized bed having a dense-phase portion and an entrained-phase portion for the combustion of fuel material. A first set of heat transfer elements connected to a steam drum is vertically disposed above the dense-phase fluidized bed to form a first flow circuit for heat transfer fluid which is heated primarily by the entrained-phase fluidized bed. A second set of heat transfer elements connected to the steam drum and forming the wall structure of the furnace provides a second flow circuit for the heat transfer fluid, the lower portion of which is heated by the dense-phase fluidized bed and the upper portion by the entrained-phase fluidized bed.

  19. Batch and fixed-bed adsorption of tartrazine azo-dye onto activated carbon prepared from apricot stones

    NASA Astrophysics Data System (ADS)

    Albroomi, H. I.; Elsayed, M. A.; Baraka, A.; Abdelmaged, M. A.

    2016-02-01

    This work describes the potential of utilizing prepared activated carbon from apricot stones as an efficient adsorbent material for tartrazine (TZ) azo-dye removal in a batch and dynamic adsorption system. The results revealed that activated carbons with well-developed surface area (774 m2/g) and pore volume (1.26 cm3/g) can be manufactured from apricot stones by H3PO4 activation. In batch experiments, effects of the parameters such as initial dye concentration and temperature on the removal of the dye were studied. Equilibrium was achieved in 120 min. Adsorption capacity was found to be dependent on the initial concentration of dye solution, and maximum adsorption was found to be 76 mg/g at 100 mg/L of TZ. The adsorption capacity at equilibrium (q e) increased from 22.6 to 76 mg/g with an increase in the initial dye concentrations from 25 to 100 mg/L. The thermodynamic parameters such as change in free energy (ΔG 0), enthalpy (ΔH 0) and entropy (ΔS 0) were determined and the positive value of (ΔH) 78.1 (K J mol-1) revealed that adsorption efficiency increased with an increase in the process temperature. In fixed-bed column experiments, the effect of selected operating parameters such as bed depth, flow rate and initial dye concentration on the adsorption capacity was evaluated. Increase in bed height of adsorption columns leads to an extension of breakthrough point as well as the exhaustion time of adsorbent. However, the maximum adsorption capacities decrease with increases of flow rate. The breakthrough data fitted well to bed depth service time and Thomas models with high coefficient of determination, R 2 ≥ 94.

  20. Magnetic fluid poly(ethylene glycol) with moderate anticancer activity

    NASA Astrophysics Data System (ADS)

    Závišová, Vlasta; Koneracká, Martina; Múčková, Marta; Lazová, Jana; Juríková, Alena; Lancz, Gábor; Tomašovičová, Natália; Timko, Milan; Kováč, Jozef; Vávra, Ivo; Fabián, Martin; Feoktystov, Artem V.; Garamus, Vasil M.; Avdeev, Mikhail V.; Kopčanský, Peter

    2011-05-01

    Poly(ethylene glycol) (PEG)-containing magnetic fluids - magnetite (Fe 3O 4) stabilized by sodium oleate - were prepared. Magnetic measurements confirmed superparamagnetic behaviour at room temperature. The structure of that kind of magnetic fluid was characterized using different techniques, including electron microscopy, photon cross correlation spectroscopy and small-angle neutron scattering, while the adsorption of PEG on magnetic particles was analyzed by differential scanning calorimetry and Fourier transform infrared spectroscopy. From the in vitro toxicity tests it was found that a magnetic fluid containing PEG (MFPEG) partially inhibited the growth of cancerous B16 cells at the highest tested dose (2.1 mg/ml of Fe 3O 4 in MFPEG).

  1. Young asteroidal fluid activity revealed by absolute age from apatite in carbonaceous chondrite

    PubMed Central

    Zhang, Ai-Cheng; Li, Qiu-Li; Yurimoto, Hisayoshi; Sakamoto, Naoya; Li, Xian-Hua; Hu, Sen; Lin, Yang-Ting; Wang, Ru-Cheng

    2016-01-01

    Chondritic meteorites, consisting of the materials that have formed in the early solar system (ESS), have been affected by late thermal events and fluid activity to various degrees. Determining the timing of fluid activity in ESS is of fundamental importance for understanding the nature, formation, evolution and significance of fluid activity in ESS. Previous investigations have determined the relative ages of fluid activity with short-lived isotope systematics. Here we report an absolute 207Pb/206Pb isochron age (4,450±50 Ma) of apatite from Dar al Gani (DaG) 978, a type ∼3.5, ungrouped carbonaceous chondrite. The petrographic, mineralogical and geochemical features suggest that the apatite in DaG 978 should have formed during metamorphism in the presence of a fluid. Therefore, the apatite age represents an absolute age for fluid activity in an asteroidal setting. An impact event could have provided the heat to activate this young fluid activity in ESS. PMID:27682449

  2. Bisphenol A removal by a Pseudomonas aeruginosa immobilized on granular activated carbon and operating in a fluidized bed reactor.

    PubMed

    Mita, Luigi; Grumiro, Laura; Rossi, Sergio; Bianco, Carmen; Defez, Roberto; Gallo, Pasquale; Mita, Damiano Gustavo; Diano, Nadia

    2015-06-30

    Serratia rubidiae, Pseudomonas aeruginosa and Escherichia coli K12 have been studied for their ability of Bisphenol A removal from aqueous systems and biofilm formation on activated granule carbon. Mathematical equations for biodegradation process have been elaborated and discussed. P. aeruginosa was found the best strain to be employed in the process of Bisphenol A removal. The yield in BPA removal of a P. aeruginosa biofilm grown on GAC and operating in a fluidized bed reactor has been evaluated. The results confirm the usefulness in using biological activated carbon (BAC process) to remove phenol compounds from aqueous systems.

  3. Effect of particle shape of active pharmaceutical ingredients prepared by fluidized-bed jet-milling on cohesiveness.

    PubMed

    Fukunaka, Tadashi; Sawaguchi, Kohta; Golman, Boris; Shinohara, Kunio

    2005-05-01

    Milling is a common procedure to improve bioavailability of many active pharmaceutical ingredients (APIs), which typically have low solubility in water. But such micronization can yield an increase in the cohesiveness of particles. Although particle cohesiveness is desirable for tablet strength in the subsequent formulation process, increased particle cohesiveness can lead to operational difficulties in a milling equipment due to compaction of particles inside. In this article, the impact of milling via a fluidized-bed jet-mill on the cohesive strength and interparticle force was studied using Ethenzamide as a pharmaceutical model compound. As a result, the particle shape was found to affect both the tensile strength of powder bed and the interparticle cohesive force. A powder bed, having relatively high void fraction by direct tensile test, shows a positive correlation between the cohesive force and the particle sphericity, while powders with low void fraction by diametral compression test show a positive correlation between the cohesive force and the angularity of the particle.

  4. Double-bed-type extraction needle packed with activated-carbon-based sorbents for very volatile organic compounds.

    PubMed

    Ueta, Ikuo; Samsudin, Emi Liana; Mizuguchi, Ayako; Takeuchi, Hayato; Shinki, Takumi; Kawakubo, Susumu; Saito, Yoshihiro

    2014-01-01

    A novel needle-type sample preparation device was developed for the determination of very volatile organic compounds (VVOCs) in gaseous samples by gas chromatography-mass spectrometry (GC-MS). Two types of activated-carbon-based sorbents, Carbopack X and a carbon molecular sieve (CMS), were investigated as the extraction medium. A double-bed-type extraction needle showed successful extraction and desorption performance for all investigated VVOCs, including acetaldehyde, isoprene, pentane, acetone, and ethanol. Sensitive and reliable determination of VVOCs was achieved by systematically optimizing several desorption conditions. In addition, the effects of sample humidity on the extraction and desorption of analytes were investigated with the needle-type extraction devices. Only the CMS packed extraction needle was adversely affected by sample humidity during the desorption process; on the other hand the double-bed-type extraction needle was unaffected by sample humidity. Finally, the developed double-bed-type extraction needle was successfully applied to the analysis of breath VVOCs of healthy subjects.

  5. Effect of three day bed-rest on circulatory and hormonal responses to active orthostatic test in endurance trained athletes and untrained subjects

    NASA Technical Reports Server (NTRS)

    Kubala, P.; Smorawinski, J.; Kaciuba-Uscilko, H.; Nazar, K.; Bicz, B.; Greenleaf, J. E.

    1996-01-01

    Circulatory and hormonal parameters were measured in endurance-trained athletes and control subjects during orthostatic tolerance tests conducted prior to and after three days of bed rest. Heart rate and blood pressure changes due to bed rest appeared to be the same in both groups. Hormonal changes, however, were different between the two groups, with the athletes having decreased sympathoadrenal activity and increased plasma renin activity. Untrained subjects had changes in cortisol secretion only.

  6. Development and testing of heat transport fluids for use in active solar heating and cooling systems

    NASA Technical Reports Server (NTRS)

    Parker, J. C.

    1981-01-01

    Work on heat transport fluids for use with active solar heating and cooling systems is described. Program objectives and how they were accomplished including problems encountered during testing are discussed.

  7. Measurement of alkali vapor in PFBC flue gas and its control by a fixed granular bed of activated bauxite

    SciTech Connect

    Lee, S.H.D.; Myles, K.M.

    1985-01-01

    A fixed granular-bed sorber, with regenerable activated bauxite as the sorbent, for the control of the alkali vapor in the flue gas produced during pressurized fluidized-bed combustion (PFBC) of coal is being developed. In a gas stream closely simulating the actual PFBC flue gas, activated bauxite is shown to capture NaCl vapor by (1) chemical fixation of the vapor with the intrinsic clay minerals, probably to form thermally stable, water-insoluble sodium aluminosilicates and (2) chemical conversion of NaCl vapor into a condensed-phase sodium sulfate, which has a much lower vapor pressure than does NaCl. The latter predominates the capture process, and the captured sodium sulfate can be easily removed by simple water-leaching to restore the porosity of activated bauxite for reuse. A high-temperature (less than or equal to 900/sup 0/C) and high-pressure (less than or equal to 10 atm) laboratory-scale, fixed, granular-bed alkali sorber has been operated with the Argonne National Laboratory PFBC combustor to (1) measure the alkali vapor concentration in the PFBC flue gas on a real-time, on-line basis, and (2) demonstrate the alkali sorber for the control of alkali vapor from an actual PFBC flue gas. The alkali (Na + K) vapor concentration in particulate filtered hot flue gas was measured to be <10 ppbW with the Ames analyzer. The same measurement with the APST was higher between 90 to 170 ppbW. Therefore, the possibility of sink for sodium vapor in the PFBC/alkali sorber system must be considered. 32 refs.

  8. Removal of Pb(II) ions from aqueous solution using activated tea waste: Adsorption on a fixed-bed column.

    PubMed

    Mondal, M K

    2009-08-01

    An inexpensive and effective adsorbent was developed from waste tea leaves for the dynamic uptake of Pb(II). Characterization of the adsorbents showed a clear change between physico-chemical properties of activated tea waste and simply tea waste. The purpose of this work was to evaluate the potential of activated tea waste in continuous flow removal of Pb(II) ions from synthetic aqueous effluents. The performance of the system was evaluated to assess the effect of various process variables, viz., of bed height, hydraulic loading rate and initial feed concentration on breakthrough time and adsorption capacity. The shape of the breakthrough curves was determined for the adsorption of Pb(II) by varying different operating parameters like hydraulic loading rate (2.3-9.17m(3)/hm(2)), bed height (0.3-0.5m) and feed concentration (2-10mg/l). An attempt has also been made to model the data generated from column studies using the empirical relationship based on the Bohart-Adams model. There was an acceptable degree of agreement between the data for breakthrough time calculated from the Bohart-Adams model and the present experimental study with average absolute deviation of less than 5.0%. The activated tea waste in this study showed very good promise as compared with the other adsorbents available in the literature. The adsorbent could be suitable for repeated use (for more than four cycles) without noticeable loss of capacity.

  9. Tapered bed bioreactor

    DOEpatents

    Scott, Charles D.; Hancher, Charles W.

    1977-01-01

    A vertically oriented conically shaped column is used as a fluidized bed bioreactor wherein biologically catalyzed reactions are conducted in a continuous manner. The column utilizes a packing material a support having attached thereto a biologically active catalytic material.

  10. Adsorption of p-nitrophenol on activated carbon fixed-bed.

    PubMed

    Sabio, E; Zamora, F; Gañan, J; González-García, C M; González, J F

    2006-09-01

    Carbon fixed-beds are usually used to remove organic contaminants. Adsorption in a carbon filter is a dynamic, non-steady process which is not yet completely understood. The objective of this paper is to establish a methodology to simplify the study of this process based on the wave theory, rapid small-scale column test and experimental design/surface response analysis. The constant pattern wave hypothesis was confirmed by the experimental data. The influence of the inlet concentration of p-nitrophenol and the flow rate on dynamic adsorption was studied at 20 degrees C following a central composite design using a second-order model. Both parameters have an important influence on the response variables studied. The methodology used is a useful tool for studying the dynamic process and shows interactions that are difficult to verify by the classical step-by-step method.

  11. Batch and fixed bed adsorption of levofloxacin on granular activated carbon from date (Phoenix dactylifera L.) stones by KOH chemical activation.

    PubMed

    Darweesh, Teeba M; Ahmed, Muthanna J

    2017-03-01

    Granular activated carbon (KAC) was prepared from abundant Phoenix dactylifera L. stones by microwave- assisted KOH activation. The characteristics of KAC were tested by pore analyses, scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR). The adsorption behavior of levofloxacin (LEV) antibiotic on KAC with surface area of 817m(2)/g and pore volume of 0.638cm(3)/g were analyzed using batch and fixed bed systems. The equilibrium data collected by batch experiments were well fitted with Langmuir compared to Freundlich and Temkin isotherms. The effect of flow rate (0.5-1.5ml/min), bed height (15-25cm), and initial LEV concentration (75-225mg/l) on the behavior of breakthrough curves was explained. The fixed bed analysis showed the better correlation of breakthrough data by both Thomas and Yoon-Nelson models. High LEV adsorption capacity of 100.3mg/g was reported on KAC, thus being an efficient adsorbent for antibiotic pollutants to protect ecological systems.

  12. Nanoporous activated carbon fluidized bed catalytic oxidations of aqueous o, p and m-cresols: kinetic and thermodynamic studies.

    PubMed

    Karthikeyan, S; Sekaran, G; Gupta, V K

    2013-07-01

    Nanoporous activated carbon prepared from rice husk through precarbonisation at 400 °C and phosphoric acid activation at 800 °C was used as fluidized bed in Fenton oxidation of the o, p and m-cresols in aqueous solution. The efficiencies of homogeneous Fenton oxidation, fluidized Fenton oxidation and aerobic biological oxidation systems for the removal of o, p and m-cresols in aqueous solution have been compared. The kinetic constants and the thermodynamic parameters for the homogeneous Fenton, heterogeneous Fenton and aerobic biological oxidations of o, p and m-cresols in synthetic wastewater were determined. The degradation of cresols in synthetic wastewater was confirmed using FT-IR, (1)H-NMR and UV-visible spectroscopy.

  13. 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.

  14. Biparticle fluidized bed reactor

    DOEpatents

    Scott, C.D.; Marasco, J.A.

    1996-02-27

    A fluidized bed reactor system is described which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary and tertiary particulate phases, continuously introduced and removed simultaneously in the cocurrent and countercurrent mode, act in a role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Means for introducing and removing the sorbent phases include feed screw mechanisms and multivane slurry valves. 3 figs.

  15. Biparticle fluidized bed reactor

    DOEpatents

    Scott, C.D.; Marasco, J.A.

    1995-04-25

    A fluidized bed reactor system utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figs.

  16. Biparticle fluidized bed reactor

    DOEpatents

    Scott, Charles D.

    1993-01-01

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves.

  17. Biparticle fluidized bed reactor

    DOEpatents

    Scott, Charles D.; Marasco, Joseph A.

    1996-01-01

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary and tertiary particulate phases, continuously introduced and removed simultaneously in the cocurrent and countercurrent mode, act in a role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Means for introducing and removing the sorbent phases include feed screw mechanisms and multivane slurry valves.

  18. Biparticle fluidized bed reactor

    DOEpatents

    Scott, Charles D.; Marasco, Joseph A.

    1995-01-01

    A fluidized bed reactor system utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves.

  19. Biparticle fluidized bed reactor

    DOEpatents

    Scott, C.D.

    1993-12-14

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase is described. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figures.

  20. Neuraminidase Activity and Resistance of 2009 Pandemic H1N1 Influenza Virus to Antiviral Activity in Bronchoalveolar Fluid

    PubMed Central

    Ruangrung, Kanyarat; Suptawiwat, Ornpreya; Maneechotesuwan, Kittipong; Boonarkart, Chompunuch; Chakritbudsabong, Warunya; Assawabhumi, Jirawatna; Bhattarakosol, Parvapan; Uiprasertkul, Mongkol; Puthavathana, Pilaipan; Wiriyarat, Witthawat; Jongkaewwattana, Anan

    2016-01-01

    ABSTRACT Human bronchoalveolar fluid is known to have anti-influenza activity. It is believed to be a frontline innate defense against the virus. Several antiviral factors, including surfactant protein D, are believed to contribute to the activity. The 2009 pandemic H1N1 influenza virus was previously shown to be less sensitive to surfactant protein D. Nevertheless, whether different influenza virus strains have different sensitivities to the overall anti-influenza activity of human bronchoalveolar fluid was not known. We compared the sensitivities of 2009 pandemic H1N1, seasonal H1N1, and seasonal H3N2 influenza virus strains to inhibition by human bronchoalveolar lavage (BAL) fluid. The pandemic and seasonal H1N1 strains showed lower sensitivity to human BAL fluid than the H3N2 strains. The BAL fluid anti-influenza activity could be enhanced by oseltamivir, indicating that the viral neuraminidase (NA) activity could provide resistance to the antiviral defense. In accordance with this finding, the BAL fluid anti-influenza activity was found to be sensitive to sialidase. The oseltamivir resistance mutation H275Y rendered the pandemic H1N1 virus but not the seasonal H1N1 virus more sensitive to BAL fluid. Since only the seasonal H1N1 but not the pandemic H1N1 had compensatory mutations that allowed oseltamivir-resistant strains to maintain NA enzymatic activity and transmission fitness, the resistance to BAL fluid of the drug-resistant seasonal H1N1 virus might play a role in viral fitness. IMPORTANCE Human airway secretion contains anti-influenza activity. Different influenza strains may vary in their susceptibilities to this antiviral activity. Here we show that the 2009 pandemic and seasonal H1N1 influenza viruses were less sensitive to human bronchoalveolar lavage (BAL) fluid than H3N2 seasonal influenza virus. The resistance to the pulmonary innate antiviral activity of the pandemic virus was determined by its neuraminidase (NA) gene, and it was shown that the

  1. Modeling competitive adsorption of mixtures of volatile organic compounds in a fixed-bed of beaded activated carbon.

    PubMed

    Tefera, Dereje Tamiru; Hashisho, Zaher; Philips, John H; Anderson, James E; Nichols, Mark

    2014-05-06

    A two-dimensional mathematical model was developed to study competitive adsorption of n-component mixtures in a fixed-bed adsorber. The model consists of an isotherm equation to predict adsorption equilibria of n-component volatile organic compounds (VOCs) mixture from single component isotherm data, and a dynamic adsorption model, the macroscopic mass, energy and momentum conservation equations, to simulate the competitive adsorption of the n-components onto a fixed-bed of adsorbent. The model was validated with experimentally measured data of competitive adsorption of binary and eight-component VOCs mixtures onto beaded activated carbon (BAC). The mean relative absolute error (MRAE) was used to compare the modeled and measured breakthrough profiles as well as the amounts of adsorbates adsorbed. For the binary and eight-component mixtures, the MRAE of the breakthrough profiles was 13 and 12%, respectively, whereas, the MRAE of the adsorbed amounts was 1 and 2%, respectively. These data show that the model provides accurate prediction of competitive adsorption of multicomponent VOCs mixtures and the competitive adsorption isotherm equation is able to accurately predict equilibrium adsorption of VOCs mixtures.

  2. Metabolic Potential and Activity in Fluids of the Coast Range Ophiolite Microbial Observatory, California, USA

    NASA Technical Reports Server (NTRS)

    Hoehler, T.; Som, S.; Schrenk, M.; McCollom, T.; Cardace, D.

    2016-01-01

    Metabolic potential and activity associated with hydrogen and carbon monoxide were characterized in fluids sampled from the the Coast Range Ophiolite Microbial Observatory (CROMO). CROMO consists of two clusters of science-dedicated wells drilled to varying depths up to 35m in the actively serpentinizing, Jurassic-age Coast Range Ophiolite of Northern California, along with a suite of pre-existing monitoring wells at the same site. Consistent with the fluid chemistry observed in other serpentinizing systems, CROMO fluids are highly alkaline, with pH up to 12.5, high in methane, with concentrations up 1600 micromolar, and low in dissolved inorganic carbon (DIC), with concentrations of 10's to 100's of micromolar. CROMO is conspicuous for fluid H2 concentrations that are consistently sub-micromolar, orders of magnitude lower than is typical of other systems. However, higher H2 concentrations (10's -100's of micromolar) at an earlier stage of fluid chemical evolution are predicted by, or consistent with: thermodynamic models for fluid chemistry based on parent rock composition equivalent to local peridotite and with water:rock ratio constrained by observed pH; the presence of magnetite at several wt% in CROMO drill cores; and concentrations of formate and carbon monoxide that would require elevated H2 if formed in equilibrium with H2 and DIC. Calculated Gibbs energy changes for reaction of H2 and CO in each of several metabolisms, across the range of fluid composition encompassed by the CROMO wells, range from bioenergetically feasible (capable of driving ATP synthesis) to thermodynamically unfavorable. Active consumption relative to killed controls was observed for both CO and H2 during incubation of fluids from the pre-existing monitoring wells; in incubations of freshly cored solids, consumption was only observed in one sample set (corresponding to the lowest pH) out of three. The specific metabolisms by which H2 and CO are consumed remain to be determined.

  3. Nanocalorimetric Characterization of Microbial Activity in Deep Subsurface Oceanic Crustal Fluids.

    PubMed

    Robador, Alberto; LaRowe, Douglas E; Jungbluth, Sean P; Lin, Huei-Ting; Rappé, Michael S; Nealson, Kenneth H; Amend, Jan P

    2016-01-01

    Although fluids within the upper oceanic basaltic crust harbor a substantial fraction of the total prokaryotic cells on Earth, the energy needs of this microbial population are unknown. In this study, a nanocalorimeter (sensitivity down to 1.2 nW ml(-1)) was used to measure the enthalpy of microbially catalyzed reactions as a function of temperature in samples from two distinct crustal fluid aquifers. Microorganisms in unamended, warm (63°C) and geochemically altered anoxic fluids taken from 292 meters sub-basement (msb) near the Juan de Fuca Ridge produced 267.3 mJ of heat over the course of 97 h during a step-wise isothermal scan from 35.5 to 85.0°C. Most of this heat signal likely stems from the germination of thermophilic endospores (6.66 × 10(4) cells ml(-1) FLUID) and their subsequent metabolic activity at temperatures greater than 50°C. The average cellular energy consumption (5.68 pW cell(-1)) reveals the high metabolic potential of a dormant community transported by fluids circulating through the ocean crust. By contrast, samples taken from 293 msb from cooler (3.8°C), relatively unaltered oxic fluids, produced 12.8 mJ of heat over the course of 14 h as temperature ramped from 34.8 to 43.0°C. Corresponding cell-specific energy turnover rates (0.18 pW cell(-1)) were converted to oxygen uptake rates of 24.5 nmol O2 ml(-1) FLUID d(-1), validating previous model predictions of microbial activity in this environment. Given that the investigated fluids are characteristic of expansive areas of the upper oceanic crust, the measured metabolic heat rates can be used to constrain boundaries of habitability and microbial activity in the oceanic crust.

  4. Fluids in crustal deformation: Fluid flow, fluid-rock interactions, rheology, melting and resources

    NASA Astrophysics Data System (ADS)

    Lacombe, Olivier; Rolland, Yann

    2016-11-01

    Fluids exert a first-order control on the structural, petrological and rheological evolution of the continental crust. Fluids interact with rocks from the earliest stages of sedimentation and diagenesis in basins until these rocks are deformed and/or buried and metamorphosed in orogens, then possibly exhumed. Fluid-rock interactions lead to the evolution of rock physical properties and rock strength. Fractures and faults are preferred pathways for fluids, and in turn physical and chemical interactions between fluid flow and tectonic structures, such as fault zones, strongly influence the mechanical behaviour of the crust at different space and time scales. Fluid (over)pressure is associated with a variety of geological phenomena, such as seismic cycle in various P-T conditions, hydrofracturing (including formation of sub-horizontal, bedding-parallel veins), fault (re)activation or gravitational sliding of rocks, among others. Fluid (over)pressure is a governing factor for the evolution of permeability and porosity of rocks and controls the generation, maturation and migration of economic fluids like hydrocarbons or ore forming hydrothermal fluids, and is therefore a key parameter in reservoir studies and basin modeling. Fluids may also help the crust partially melt, and in turn the resulting melt may dramatically change the rheology of the crust.

  5. Elastically cooperative activated barrier hopping theory of relaxation in viscous fluids. I. General formulation and application to hard sphere fluids.

    PubMed

    Mirigian, Stephen; Schweizer, Kenneth S

    2014-05-21

    We generalize the force-level nonlinear Langevin equation theory of single particle hopping to include collective effects associated with long range elastic distortion of the liquid. The activated alpha relaxation event is of a mixed spatial character, involving two distinct, but inter-related, local and collective barriers. There are no divergences at volume fractions below jamming or temperatures above zero Kelvin. The ideas are first developed and implemented analytically and numerically in the context of hard sphere fluids. In an intermediate volume fraction crossover regime, the local cage process is dominant in a manner consistent with an apparent Arrhenius behavior. The super-Arrhenius collective barrier is more strongly dependent on volume fraction, dominates the highly viscous regime, and is well described by a nonsingular law below jamming. The increase of the collective barrier is determined by the amplitude of thermal density fluctuations, dynamic shear modulus or transient localization length, and a growing microscopic jump length. Alpha relaxation time calculations are in good agreement with recent experiments and simulations on dense fluids and suspensions of hard spheres. Comparisons of the theory with elastic models and entropy crisis ideas are explored. The present work provides a foundation for constructing a quasi-universal, fit-parameter-free theory for relaxation in thermal molecular liquids over 14 orders of magnitude in time.

  6. Pulsed atmospheric fluidized bed combustion

    SciTech Connect

    Not Available

    1992-10-01

    The design of the Pulsed Atmospheric Fluidized Bed Combustor (PAFBC) as described in the Quarterly Report for the period April--June, 1992 was reviewed and minor modifications were included. The most important change made was in the coal/limestone preparation and feed system. Instead of procuring pre-sized coal for testing of the PAFBC, it was decided that the installation of a milling system would permit greater flexibility in the testing with respect to size distributions and combustion characteristics in the pulse combustor and the fluid bed. Particle size separation for pulse combustor and fluid bed will be performed by an air classifier. The modified process flow diagram for the coal/limestone handling system is presented in Figure 1. The modified process flow diagrams of the fluidized bed/steam cycle and ash handling systems are presented in Figures 2 and 3, respectively.

  7. Implications of perennial saline springs for abnormally high fluid pressures and active thrusting in western California

    SciTech Connect

    Unruh, J.R.; Davisson, M.L.; Criss, R.E.; Moores, E.M. )

    1992-05-01

    Perennial saline springs in the Rumsey Hills area, southwestern Sacramento Valley, California, locally discharge at high elevations and near ridgetops. The springs are cold, are commonly associated with natural gas seeps, and typically emerge along west-vergent thrust faults. Stable isotope analyses indicate that the spring waters are similar to oil-field formation fluids and they have had a significant residence time in the subsurface at moderate temperatures. The nonmeteoric character of the springs demonstrates that they are not being fed by perched water tables. The authors propose that these subsurface formation waters are being forced to the surface by anomalously high porefluid pressures. The Rumsey Hills area is one of Quaternary uplift, thrusting, and crustal shortening, and prospect wells drilled there have encountered anomalously high fluid pressures at shallow depths. They attribute these high fluid pressures to active tectonic compression and shortening of Cretaceous marine sedimentary rocks. The widespread occurrence of anomalously high pore-fluid pressures and perennial saline springs in the Coast Ranges and western Great Valley suggests that much of western California may be characterized as a seismically active, overpressured thrust belt. The emergence of formation waters along thrust faults further suggests that patterns of subsurface fluid flow in western California may be similar to those in overpressured accretionary prisms, and that excess fluid pressures may also play a role in the distribution of seismicity.

  8. Overview of Fluid Dynamics Activities at the Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Garcia, Roberto; Griffin, Lisa W.; Wang, Ten-See

    1999-01-01

    Since its inception 40 years ago, Marshall Space Flight Center (MSFC) has had the need to maintain and advance state-of-the-art flow analysis and cold-flow testing capability to support its roles and missions. This overview discusses the recent organizational changes that have occurred at MSFC with emphasis on the resulting three groups that form the core of fluid dynamics expertise at MSFC: the Fluid Physics and Dynamics Group, the Applied Fluid Dynamics Analysis Group, and the Experimental Fluid Dynamics Group. Recently completed activities discussed include the analysis and flow testing in support of the Fastrac engine design, the X-33 vehicle design, and the X34 propulsion system design. Ongoing activities include support of the RLV vehicle design, Liquid Fly Back Booster aerodynamic configuration definition, and RLV focused technologies development. Other ongoing activities discussed are efforts sponsored by the Center Director's Discretionary Fund (CDDF) to develop an advanced incompressible flow code and to develop optimization techniques. Recently initiated programs and their anticipated required fluid dynamics support are discussed. Based on recent experiences and on the anticipated program needs, required analytical and experimental technique improvements are presented. Due to anticipated budgetary constraints, there is a strong need to leverage activities and to pursue teaming arrangements in order to advance the state-of-the-art and to adequately support concept development. Throughout this overview there is discussion of the lessons learned and of the capabilities demonstrated and established in support of the hardware development programs.

  9. Lysozyme activity in earthworm (Lumbricus terrestris) coelomic fluid and coelomocytes: Enzyme assay for immunotoxicity of xenobiotics

    SciTech Connect

    Goven, A.J.; Chen, S.C.; Fitzpatrick, L.C. . Dept. of Biological Sciences); Venables, B.J. . Dept. of Biological Sciences TRAC Laboratories Inc., Denton, TX )

    1994-04-01

    Lysozyme activity in earthworm (Lumbricus terrestris) coelomic fluid and coelomocytes appears sufficiently sensitive for use as a nonmammalian biomarker to detect toxic effects of sublethal body burdens of Cu[sup 2+]. Lysozyme, a phylogenetically conserved enzyme, is capable of bactericidal activity via action on peptidoglycan of gram-positive bacterial cell walls and functions as a component of an organism's innate antimicrobial defense mechanism. Coelomic fluid and coelomocyte lysozyme activities, which exhibit temperature-response patterns similar to those of human saliva, plasma, serum and leukocyte extracts, were sensitive to Cu[sup 2+] exposure. Lysozyme activity of coelomic fluid and coelomocyte extracts from earthworms exposed for 5 d to CuSO[sub 4], using filter paper contact exposure, decreased with increasing sublethal Cu[sup 2+] concentrations of 0.05 and 0.1 [mu]g/cm[sup 2]. Compared to controls, coelomic fluid lysozyme activity was suppressed significantly at both exposure concentrations, whereas coelomocyte extract lysozyme activity was suppressed significantly at the 0.1-[mu]g/cm[sup 2] exposure concentration. Low inherent natural variability and sensitivity to sublethal Cu[sup 2+] body burdens indicate that lysozyme activity has potential as a biomarker for assaying immunotoxicity of metals.

  10. Collective dynamics of chemically active particles trapped at a fluid interface.

    PubMed

    Domínguez, Alvaro; Malgaretti, P; Popescu, M N; Dietrich, S

    2016-10-12

    Chemically active colloids generate changes in the chemical composition of their surrounding solution and thereby induce flows in the ambient fluid which affect their dynamical evolution. Here we study the many-body dynamics of a monolayer of spherically symmetric active particles trapped at a fluid-fluid interface. To this end we consider a model for the large-scale spatial distribution of particles which incorporates the direct pair interaction (including also the capillary interaction which is caused specifically by the interfacial trapping) as well as the effect of hydrodynamic interactions (including the Marangoni flow induced by the response of the interface to the chemical activity). The values of the relevant physical parameters for typical experimental realizations of such systems are estimated and various scenarios, which are predicted by our approach for the dynamics of the monolayer, are discussed. In particular, we show that the chemically-induced Marangoni flow can prevent the clustering instability driven by the capillary attraction.

  11. Active modal control simulation of vibro-acoustic response of a fluid-loaded plate

    NASA Astrophysics Data System (ADS)

    Li, Sheng

    2011-11-01

    Active modal control simulation of vibro-acoustic response of a fluid-loaded plate is presented. The active modal control of the vibro-acoustic response is implemented using piezoelectric actuators/sensors. The active modal damping is added to the coupled system via negative velocity feedback. The feedback gain between the piezoelectric actuators/sensors for the modal control is obtained using the in-vacuo modal matrix and the incompressible fluid-loaded modal matrix. The modal control performance of structural vibration and acoustic radiation of a baffled plate is numerically studied. It is shown that the proposed method increases the modal damping ratio and achieves reduction in the mean square velocity and the sound power for given modes of the fluid-loaded plate.

  12. Unit with Fluidized Bed for Gas-Vapor Activation of Different Carbonaceous Materials for Various Purposes: Design, Computation, Implementation.

    PubMed

    Strativnov, Eugene

    2017-12-01

    We propose the technology of obtaining the promising material with wide specter of application-activated nanostructured carbon. In terms of technical indicators, it will stand next to the materials produced by complex regulations with the use of costly chemical operations. It can be used for the following needs: as a sorbent for hemosorption and enterosorption, for creation of the newest source of electric current (lithium and zinc air batteries, supercapacitors), and for processes of short-cycle adsorption gas separation.In this study, the author gives recommendations concerning the design of the apparatus with fluidized bed and examples of calculation of specific devices. The whole given information can be used as guidelines for the design of energy effective aggregates. Calculation and design of the reactor were carried out using modern software complexes (ANSYS and SolidWorks).

  13. Biodegradation of benzotriazoles and hydroxy-benzothiazole in wastewater by activated sludge and moving bed biofilm reactor systems.

    PubMed

    Mazioti, Aikaterini A; Stasinakis, Athanasios S; Pantazi, Ypapanti; Andersen, Henrik R

    2015-09-01

    Two laboratory scale fully aerated continuous flow wastewater treatment systems were used to compare the removal of five benzotriazoles and one benzothiazole by suspended and attached growth biomass. The activated sludge system was operated under low organic loading conditions. The moving bed biofilm reactor (MBBR) system consisted of two serially connected reactors filled with K3-biocarriers. It was either operated under low or high organic loading conditions. Target compounds were removed partially and with different rates in tested systems. For MBBR, increased loading resulted in significantly lower biodegradation for 4 out of 6 examined compounds. Calculation of specific removal rates (normalized to biomass) revealed that attached biomass had higher biodegradation potential for target compounds comparing to suspended biomass. Clear differences in the biodegradation ability of attached biomass grown in different bioreactors of MBBR systems were also observed. Batch experiments showed that micropollutants biodegradation by both types of biomass is co-metabolic.

  14. Assessment of rheumatoid activity based on clinical features and blood and synovial fluid analysis.

    PubMed Central

    Farr, M; Kendall, M J; Young, D W; Meynell, M J; Hawkins, C F

    1976-01-01

    Joint inflammation in rheumatoid arthritis has been assessed, and the most useful guides to disease activity were determined by analysis of synovial fluid and blood together with the history of joint disability. The patient's own evaluation of the amount of pain suffered was the most useful clinical assessment. Differential cell count and glucose estimations were the most helpful guides in the synovial fluid, while C-reactive protein in the serum most accurately reflected disease activity. The effects of systemic steroids on these indices were studied, and the differences between seronegative and seropositive patients noted. PMID:942273

  15. Upgrade of deep bed filtration with activated carbon dosage for compact micropollutant removal from wastewater in technical scale.

    PubMed

    Löwenberg, Jonas; Zenker, Armin; Krahnstöver, Thérèse; Boehler, Marc; Baggenstos, Martin; Koch, Gerhard; Wintgens, Thomas

    2016-05-01

    The removal of micropollutants from drinking and wastewater by powdered activated carbon (PAC) adsorption has received considerable attention in research over the past decade with various separation options having been investigated. With Switzerland as the first country in the world having adopted a new legislation, which forces about 100 wastewater treatment plants to be upgraded for the removal of organic micropollutants from municipal wastewater, the topic has reached practical relevance. In this study, the process combination of powdered activated carbon (PAC) adsorption and deep bed filtration (DBF) for advanced municipal wastewater treatment was investigated over an extended period exceeding one year of operation in technical scale. The study aimed to determine optimum process conditions to achieve sufficient micropollutant removal in agreement with the new Swiss Water Ordinance under most economic process design. It was shown that the addition of PAC and Fe(3+) as combined coagulation and flocculation agent improved effluent water quality with respect to dissolved organic pollutants as well as total suspended solids (TSS), turbidity and PO4-P concentration in comparison to a DBF operated without the addition of PAC and Fe(3+). Sufficient micropollutant (MP) removal of around 80% was achieved at PAC dosages of 10 mg/L revealing that PAC retained in the filter bed maintained considerable adsorption capacity. In the investigated process combination the contact reactor serves for adsorption as well as for flocculation and allowed for small hydraulic retention times of minimum 10 min while maintaining sufficient MP removal. The flocculation of two different PAC types was shown to be fully concluded after 10-15 min, which determined the flocculation reactor size while both PAC types proved suitable for the application in combination with DBF and showed no significant differences in MP removal. Finally, the capping of PAC dosage during rain water periods, which

  16. TRY-5 Is a Sperm-Activating Protease in Caenorhabditis elegans Seminal Fluid

    PubMed Central

    Smith, Joseph R.; Stanfield, Gillian M.

    2011-01-01

    Seminal fluid proteins have been shown to play important roles in male reproductive success, but the mechanisms for this regulation remain largely unknown. In Caenorhabditis elegans, sperm differentiate from immature spermatids into mature, motile spermatozoa during a process termed sperm activation. For C. elegans males, sperm activation occurs during insemination of the hermaphrodite and is thought to be mediated by seminal fluid, but the molecular nature of this activity has not been previously identified. Here we show that TRY-5 is a seminal fluid protease that is required in C. elegans for male-mediated sperm activation. We observed that TRY-5::GFP is expressed in the male somatic gonad and is transferred along with sperm to hermaphrodites during mating. In the absence of TRY-5, male seminal fluid loses its potency to transactivate hermaphrodite sperm. However, TRY-5 is not required for either hermaphrodite or male fertility, suggesting that hermaphrodite sperm are normally activated by a distinct hermaphrodite-specific activator to which male sperm are also competent to respond. Within males, TRY-5::GFP localization within the seminal vesicle is antagonized by the protease inhibitor SWM-1. Together, these data suggest that TRY-5 functions as an extracellular activator of C. elegans sperm. The presence of TRY-5 within the seminal fluid couples the timing of sperm activation to that of transfer of sperm into the hermaphrodite uterus, where motility must be rapidly acquired. Our results provide insight into how C. elegans has adopted sex-specific regulation of sperm motility to accommodate its male-hermaphrodite mode of reproduction. PMID:22125495

  17. TRY-5 is a sperm-activating protease in Caenorhabditis elegans seminal fluid.

    PubMed

    Smith, Joseph R; Stanfield, Gillian M

    2011-11-01

    Seminal fluid proteins have been shown to play important roles in male reproductive success, but the mechanisms for this regulation remain largely unknown. In Caenorhabditis elegans, sperm differentiate from immature spermatids into mature, motile spermatozoa during a process termed sperm activation. For C. elegans males, sperm activation occurs during insemination of the hermaphrodite and is thought to be mediated by seminal fluid, but the molecular nature of this activity has not been previously identified. Here we show that TRY-5 is a seminal fluid protease that is required in C. elegans for male-mediated sperm activation. We observed that TRY-5::GFP is expressed in the male somatic gonad and is transferred along with sperm to hermaphrodites during mating. In the absence of TRY-5, male seminal fluid loses its potency to transactivate hermaphrodite sperm. However, TRY-5 is not required for either hermaphrodite or male fertility, suggesting that hermaphrodite sperm are normally activated by a distinct hermaphrodite-specific activator to which male sperm are also competent to respond. Within males, TRY-5::GFP localization within the seminal vesicle is antagonized by the protease inhibitor SWM-1. Together, these data suggest that TRY-5 functions as an extracellular activator of C. elegans sperm. The presence of TRY-5 within the seminal fluid couples the timing of sperm activation to that of transfer of sperm into the hermaphrodite uterus, where motility must be rapidly acquired. Our results provide insight into how C. elegans has adopted sex-specific regulation of sperm motility to accommodate its male-hermaphrodite mode of reproduction.

  18. Study of ebullated-bed fluid dynamics for h-coal. Quarterly progress report No. 2, October 1-December 31, 1980

    SciTech Connect

    Schaefer, R. J.; Rundell, D. N.

    1981-01-01

    Analysis of data from the fluid dynamics tests performed at Hydrocarbon Research, Inc., during Run PDU-10 was started. Data in the computer files were cross-checked with the original notebooks to verify accuracy. Gamma-ray mass absorption coefficients for material in the PDU reactor were calculated using characterization of selected oil and catalyst samples. Battelle Institute began viscosity measurement of PDU reactor liquid samples. Northwestern University began shakedown of the 6'' diameter test stand. Model fluids were selected and charged to the unit. Optical components were designed and assembly was started.

  19. Alkali activation of recovered fuel-biofuel fly ash from fluidised-bed combustion: Stabilisation/solidification of heavy metals.

    PubMed

    Yliniemi, Juho; Pesonen, Janne; Tiainen, Minna; Illikainen, Mirja

    2015-09-01

    Recovered fuel-biofuel fly ash from a fluidized bed boiler was alkali-activated and granulated with a sodium-silicate solution in order to immobilise the heavy metals it contains. The effect of blast-furnace slag and metakaolin as co-binders were studied. Leaching standard EN 12457-3 was applied to evaluate the immobilisation potential. The results showed that Ba, Pb and Zn were effectively immobilised. However, there was increased leaching after alkali activation for As, Cu, Mo, Sb and V. The co-binders had minimal or even negative effect on the immobilisation. One exception was found for Cr, in which the slag decreased leaching, and one was found for Cu, in which the slag increased leaching. A sequential leaching procedure was utilized to gain a deeper understanding of the immobilisation mechanism. By using a sequential leaching procedure it is possible fractionate elements into watersoluble, acid-soluble, easily-reduced and oxidisable fractions, yielding a total 'bioavailable' amount that is potentially hazardous for the environment. It was found that the total bioavailable amount was lower following alkali activation for all heavy metals, although the water-soluble fraction was higher for some metals. Evidence from leaching tests suggests the immobilisation mechanism was chemical retention, or trapping inside the alkali activation reaction products, rather than physical retention, adsorption or precipitation as hydroxides.

  20. Alkali metal vapor removal from pressurized fluidized-bed combustor flue gas: activated bauxite sorbent regeneration. Quarterly report, October-December 1980

    SciTech Connect

    Johnson, I.; Lee, S.H.D.

    1981-05-01

    This work supports the program to develop methods for the cleanup of combustion gases from pressurized fluidized-bed coal combustors so that the cleaned gases can be used to power downstream gas turbines. Presented here are the results of studies to develop granular sorbents for removing gaseous alkali metal compounds from these combustion gases in a granular-bed filter. Activated bauxite bed material can be reused after the alkali compound is removed by a water-leaching process. In experiments to study the kinetics of leaching, the effects of adsorbed NaCl loading, leaching temperature, and the leaching water to sorbent ratio on the rate of leaching are reported. Also reported are water retention in bauxite after leaching and the effect of volatile alkalis in makeup activated bauxite on the alkali level in flue gas expanded in the gas turbine.

  1. Comparison of Active Drug Concentrations in the Pulmonary Epithelial Lining Fluid and Interstitial Fluid of Calves Injected with Enrofloxacin, Florfenicol, Ceftiofur, or Tulathromycin.

    PubMed

    Foster, Derek M; Martin, Luke G; Papich, Mark G

    2016-01-01

    Bacterial pneumonia is the most common reason for parenteral antimicrobial administration to beef cattle in the United States. Yet there is little information describing the antimicrobial concentrations at the site of action. The objective of this study was to compare the active drug concentrations in the pulmonary epithelial lining fluid and interstitial fluid of four antimicrobials commonly used in cattle. After injection, plasma, interstitial fluid, and pulmonary epithelial lining fluid concentrations and protein binding were measured to determine the plasma pharmacokinetics of each drug. A cross-over design with six calves per drug was used. Following sample collection and drug analysis, pharmacokinetic calculations were performed. For enrofloxacin and metabolite ciprofloxacin, the interstitial fluid concentration was 52% and 78% of the plasma concentration, while pulmonary fluid concentrations was 24% and 40% of the plasma concentration, respectively. The pulmonary concentrations (enrofloxacin + ciprofloxacin combined) exceeded the MIC90 of 0.06 μg/mL at 48 hours after administration. For florfenicol, the interstitial fluid concentration was almost 98% of the plasma concentration, and the pulmonary concentrations were over 200% of the plasma concentrations, exceeding the breakpoint (≤ 2 μg/mL), and the MIC90 for Mannheimia haemolytica (1.0 μg/mL) for the duration of the study. For ceftiofur, penetration to the interstitial fluid was only 5% of the plasma concentration. Pulmonary epithelial lining fluid concentration represented 40% of the plasma concentration. Airway concentrations exceeded the MIC breakpoint for susceptible respiratory pathogens (≤ 2 μg/mL) for a short time at 48 hours after administration. The plasma and interstitial fluid concentrations of tulathromcyin were lower than the concentrations in pulmonary fluid throughout the study. The bronchial concentrations were higher than the plasma or interstitial concentrations, with over 900

  2. Comparison of Active Drug Concentrations in the Pulmonary Epithelial Lining Fluid and Interstitial Fluid of Calves Injected with Enrofloxacin, Florfenicol, Ceftiofur, or Tulathromycin

    PubMed Central

    Foster, Derek M.; Martin, Luke G.; Papich, Mark G.

    2016-01-01

    Bacterial pneumonia is the most common reason for parenteral antimicrobial administration to beef cattle in the United States. Yet there is little information describing the antimicrobial concentrations at the site of action. The objective of this study was to compare the active drug concentrations in the pulmonary epithelial lining fluid and interstitial fluid of four antimicrobials commonly used in cattle. After injection, plasma, interstitial fluid, and pulmonary epithelial lining fluid concentrations and protein binding were measured to determine the plasma pharmacokinetics of each drug. A cross-over design with six calves per drug was used. Following sample collection and drug analysis, pharmacokinetic calculations were performed. For enrofloxacin and metabolite ciprofloxacin, the interstitial fluid concentration was 52% and 78% of the plasma concentration, while pulmonary fluid concentrations was 24% and 40% of the plasma concentration, respectively. The pulmonary concentrations (enrofloxacin + ciprofloxacin combined) exceeded the MIC90 of 0.06 μg/mL at 48 hours after administration. For florfenicol, the interstitial fluid concentration was almost 98% of the plasma concentration, and the pulmonary concentrations were over 200% of the plasma concentrations, exceeding the breakpoint (≤ 2 μg/mL), and the MIC90 for Mannheimia haemolytica (1.0 μg/mL) for the duration of the study. For ceftiofur, penetration to the interstitial fluid was only 5% of the plasma concentration. Pulmonary epithelial lining fluid concentration represented 40% of the plasma concentration. Airway concentrations exceeded the MIC breakpoint for susceptible respiratory pathogens (≤ 2 μg/mL) for a short time at 48 hours after administration. The plasma and interstitial fluid concentrations of tulathromcyin were lower than the concentrations in pulmonary fluid throughout the study. The bronchial concentrations were higher than the plasma or interstitial concentrations, with over 900

  3. Bed exit alarms.

    PubMed

    2004-09-01

    Bed-exit alarms alert caregivers that a patient who should not get out of bed unassisted is doing so. These alarms can help reduce the likelihood of falls and can promote speedy assistance to patients who have already fallen. But as we described in our May 2004 Guidance Article on bed-exit alarms, they don't themselves prevent falls. They are only effective if used as part of an overall fall-prevention program and with a clear understanding of their limitations. This Evaluation examines the effectiveness of 16 bed-exit alarms from seven suppliers. Our ratings focus primarily on each product's reliability in detecting bed-exit events and alerting caregivers, its ability to minimize nuisance alarms (alarms that sound even though the patient isn't leaving the bed or that sound while a caregiver is helping the patient to leave the bed), and its resistance to deliberate or inadvertent tampering. Twelve of the products use pressure-sensor-activated alarms (mainly sensor pads placed on or under the mattress); three use a cord that can attach to the patient's garment, alarming if the cord is pulled loose from the control unit; and one is a position-sensitive alarm attached to a leg cuff. All the products reliably detect attempted or successful bed exits. But they vary greatly in how effectively they alert staff, minimize nuisance alarms, and resist tampering. Ease of use and battery performance also vary for many units. Of the pressure-sensor units, three are rated Preferred. Those units meet most of our criteria and have no significant disadvantages. Five of the other pressure-sensor products are Acceptable, and the remaining four are Not Recommended. All three cord-activated alarms are rated Acceptable, as is the patient-worn alarm.

  4. GREENHOUSE GAS EMISSIONS CONTROL BY OXYGEN FIRING IN CIRCULATING FLUID BED BOILERS (Phase II--Evaluation of the Oxyfuel CFB Concept)

    SciTech Connect

    John L. Marion; Nsakala ya Nsakala

    2003-11-09

    The overall project goal is to determine if carbon dioxide can be captured and sequestered at a cost of about $10/ton of carbon avoided, using a newly constructed Circulating Fluidized Bed combustor while burning coal with a mixture of oxygen and recycled flue gas, instead of air. This project is structured in two Phases. Phase I was performed between September 28, 2001 and May 15, 2002. Results from Phase I were documented in a Topical Report issued on May 15, 2003 (Nsakala, et al., 2003), with the recommendation to evaluate, during Phase II, the Oxyfuel-fired CFB concept. DOE NETL accepted this recommendation, and, hence approved the project continuation into Phase II. Phase 2. The second phase of the project--which includes pilot-scale tests of an oxygen-fired circulating fluidized bed test facility with performance and economic analyses--is currently underway at ALSTOM's Power Plant Laboratories, located in Windsor, CT (US). The objective of the pilot-scale testing is to generate detailed technical data needed to establish advanced CFB design requirements and performance when firing coals and delayed petroleum coke in oxygen/carbon dioxide mixtures. Results will be used in the design of oxygen-fired CFB boilers--both retrofit and new Greenfield--as well as to provide a generic performance database for other researchers. At the conclusion of Phase 2, revised costs and performance will be estimated for both retrofit and new Greenfield design concepts with CO2 capture, purification, compression, and liquefaction.

  5. Larvicidal and Growth-Inhibitory Activity of Entomopathogenic Bacteria Culture Fluids Against Aedes aegypti (Diptera: Culicidae).

    PubMed

    da Silva, João Luiz Rosa; Undurraga Schwalm, Fernanda; Eugênio Silva, Carlos; da Costa, Marisa; Heermann, Ralf; Santos da Silva, Onilda

    2017-01-06

    Dengue, Chikungunya, and Zika are important vector-borne diseases, and Aedes aegypti L. is their main transmitter. As the disease management is mainly based on mosquito control strategies, the search for alternative and cost-effective approaches is ongoing. The Gram-negative bacteria Xenorhabdus nematophila and Photorhabdus luminescens are symbiotically associated with entomopathogenic nematodes and are highly pathogenic for insect larvae. After we have recently confirmed the toxicity of these bacteria in Ae. aegypti larvae, we here evaluated the toxic activity of culture fluids on the development of this mosquito species. Larval susceptibility was assessed by exposing larvae to different concentrations of P. luminescens or X. nematophila culture fluids to confirm whether secondary metabolites might cause the mosquitos' death. Xenorhabdus nematophila culture fluid was more effective and stable during the mosquito pathogenicity bioassays compared to that of P. luminescens Larval mortality started a few hours after exposure of the insects to the fluids. Furthermore, the residual effect of larvicidal activity of X. nematophila fluid persisted at full efficiency for 4 d. Particularly, larval mortality was still higher than 50% for up to 8 d. Exposure of larvae to a sublethal dose of X. nematophila fluid delayed pupation as well as emergence of adult mosquitoes and caused cumulative larval mortality higher than 90% by day 14. Here, we describe for the first time the use of stable culture fluids and therefore secondary metabolites of P. luminescens and X. nematophila as a promising basis for the use as biopesticide for control of Ae. aegypti in the future.

  6. Traps of carnivorous pitcher plants as a habitat: composition of the fluid, biodiversity and mutualistic activities

    PubMed Central

    Adlassnig, Wolfram; Peroutka, Marianne; Lendl, Thomas

    2011-01-01

    Background Carnivorous pitcher plants (CPPs) use cone-shaped leaves to trap animals for nutrient supply but are not able to kill all intruders of their traps. Numerous species, ranging from bacteria to vertrebrates, survive and propagate in the otherwise deadly traps. This paper reviews the literature on phytotelmata of CPPs. Pitcher Fluid as a Habitat The volumes of pitchers range from 0·2 mL to 1·5 L. In Nepenthes and Cephalotus, the fluid is secreted by the trap; the other genera collect rain water. The fluid is usually acidic, rich in O2 and contains digestive enzymes. In some taxa, toxins or detergents are found, or the fluid is extremely viscous. In Heliamphora or Sarracenia, the fluid differs little from pure water. Inquiline Diversity Pitcher inquilines comprise bacteria, protozoa, algae, fungi, rotifers, crustaceans, arachnids, insects and amphibia. The dominant groups are protists and Dipteran larvae. The various species of CPPs host different sets of inquilines. Sarracenia purpurea hosts up to 165 species of inquilines, followed by Nepenthes ampullaria with 59 species, compared with only three species from Brocchinia reducta. Reasons for these differences include size, the life span of the pitcher as well as its fluid. Mutualistic Activities Inquilines closely interact with their host. Some live as parasites, but the vast majority are mutualists. Beneficial activities include secretion of enzymes, feeding on the plant's prey and successive excretion of inorganic nutrients, mechanical break up of the prey, removal of excessive prey and assimilation of atmospheric N2. Conclusions There is strong evidence that CPPs influence their phytotelm. Two strategies can be distinguished: (1) Nepenthes and Cephalotus produce acidic, toxic or digestive fluids and host a limited diversity of inquilines. (2) Genera without efficient enzymes such as Sarracenia or Heliamphora host diverse organisms and depend to a large extent on their symbionts for prey utilization

  7. Antifungal activity of fluid extract and essential oil from anise fruits (Pimpinella anisum L., Apiaceae).

    PubMed

    Kosalec, Ivan; Pepeljnjak, Stjepan; Kustrak, Danica

    2005-12-01

    Antifungal activities of fluid extract and essential oil obtained from anise fruits Pimpinella anisum L. (Apiaceae) were tested in vitro on clinical isolates of seven species of yeasts and four species of dermatophytes. Diffusion method with cylinders and the broth dilution method were used for antifungal activity testing. Anise fluid extract showed antimycotic activity against Candida albicans, C. parapsilosis, C. tropicalis, C. pseudotropicalis and C. krusei with MIC values between 17 and 20% (v/v). No activity was noticed against C. glabrata, and anis fruits extracts showed growth promotion activity on Geotrichum spp. Anise fruits extract inhibited the growth of dermatophyte species (Trichophyton rubrum, T. mentagrophytes, Microsporum canis and M. gypseum) with MIC values between 1.5 and 9.0% (V/V). Anise essential oil showed strong antifungal activity against yeasts with MIC lower than 1.56% (V/V) and dermatophytes with MIC lower than 0.78% (V/V). Significant differences in antifungal activities were found between anise fluid extract and anise essential oil (p<0.01). Anise essential oil exhibited stronger antifungal activities against yeasts and dermatophytes with MIC values between 0.10 and 1.56% (V/V), respectively.

  8. Factors Influencing the Measurement of Lysosomal Enzymes Activity in Human Cerebrospinal Fluid

    PubMed Central

    Parnetti, Lucilla; Eusebi, Paolo; Paciotti, Silvia; De Carlo, Claudia; Codini, Michela; Tambasco, Nicola; Rossi, Aroldo; Agnaf, Omar M. El.; Calabresi, Paolo; Beccari, Tommaso

    2014-01-01

    Measurements of the activities of lysosomal enzymes in cerebrospinal fluid have recently been proposed as putative biomarkers for Parkinson's disease and other synucleinopathies. To define the operating procedures useful for ensuring the reliability of these measurements, we analyzed several pre-analytical factors that may influence the activity of β-glucocerebrosidase, α-mannosidase, β-mannosidase, β-galactosidase, α-fucosidase, β-hexosaminidase, cathepsin D and cathepsin E in cerebrospinal fluid. Lysosomal enzyme activities were measured by well-established fluorimetric assays in a consecutive series of patients (n = 28) with different neurological conditions, including Parkinson's disease. The precision, pre-storage and storage conditions, and freeze/thaw cycles were evaluated. All of the assays showed within- and between-run variabilities below 10%. At −20°C, only cathepsin D was stable up to 40 weeks. At −80°C, the cathepsin D, cathepsin E, and β-mannosidase activities did not change significantly up to 40 weeks, while β-glucocerebrosidase activity was stable up to 32 weeks. The β-galactosidase and α-fucosidase activities significantly increased (+54.9±38.08% after 4 weeks and +88.94±36.19% after 16 weeks, respectively). Up to four freeze/thaw cycles did not significantly affect the activities of cathepsins D and E. The β-glucocerebrosidase activity showed a slight decrease (−14.6%) after two freeze/thaw cycles. The measurement of lysosomal enzyme activities in cerebrospinal fluid is reliable and reproducible if pre-analytical factors are accurately taken into consideration. Therefore, the analytical recommendations that ensue from this study may contribute to the establishment of actual values for the activities of cerebrospinal fluid lysosomal enzymes as putative biomarkers for Parkinson's disease and other neurodegenerative disorders. PMID:24983953

  9. Increased cellular activity in rat insular cortex after water and salt ingestion induced by fluid depletion.

    PubMed

    Pastuskovas, Cinthia V; Cassell, Martin D; Johnson, Alan Kim; Thunhorst, Robert L

    2003-04-01

    Insular cortex (IC) receives inputs from multiple sensory systems, including taste, and from receptors that monitor body electrolyte and fluid balance and blood pressure. This work analyzed metabolic activity of IC cells after water and sodium ingestion induced by sodium depletion. Rats were injected with the diuretic furosemide (10 mg/kg body wt), followed 5 min later by injections of the angiotensin-converting enzyme inhibitor captopril (5 mg/kg body wt). After 90 min, some rats received water and 0.3 M NaCl to drink for 2 h while others did not. A third group had access to water and saline but was not depleted of fluids. All rats were killed for processing of brain tissue for Fos-immunoreactivity (Fos-ir). Nondepleted animals had weak-to-moderate levels of Fos-ir within subregions of IC. Fluid-depleted rats without fluid access had significantly increased Fos-ir in all areas of IC. Levels of Fos-ir were highest in fluid-depleted rats that drank water and sodium. Fos-ir levels were highest in anterior regions of IC and lowest in posterior regions of IC. These results implicate visceral, taste, and/or postingestional factors in the increased metabolic activity of cells in IC.

  10. Spontaneous mirror-symmetry breaking induces inverse energy cascade in 3D active fluids

    PubMed Central

    Słomka, Jonasz; Dunkel, Jörn

    2017-01-01

    Classical turbulence theory assumes that energy transport in a 3D turbulent flow proceeds through a Richardson cascade whereby larger vortices successively decay into smaller ones. By contrast, an additional inverse cascade characterized by vortex growth exists in 2D fluids and gases, with profound implications for meteorological flows and fluid mixing. The possibility of a helicity-driven inverse cascade in 3D fluids had been rejected in the 1970s based on equilibrium-thermodynamic arguments. Recently, however, it was proposed that certain symmetry-breaking processes could potentially trigger a 3D inverse cascade, but no physical system exhibiting this phenomenon has been identified to date. Here, we present analytical and numerical evidence for the existence of an inverse energy cascade in an experimentally validated 3D active fluid model, describing microbial suspension flows that spontaneously break mirror symmetry. We show analytically that self-organized scale selection, a generic feature of many biological and engineered nonequilibrium fluids, can generate parity-violating Beltrami flows. Our simulations further demonstrate how active scale selection controls mirror-symmetry breaking and the emergence of a 3D inverse cascade. PMID:28193853

  11. Fluid flow and heat convection studies for actively cooled airframes

    NASA Astrophysics Data System (ADS)

    Mills, A. F.

    This report details progress made on the jet impingement - liquid crystal - digital imaging experiment. With the design phase complete, the experiment is currently in the construction phase. In order to reach this phase two design related issues were resolved. The first issue was to determine NASP leading edge active cooling design parameters. Meetings were arranged with personnel at SAIC International, Torrance, CA in order to obtain recent publications that characterized expected leading edge heat fluxes as well as other details of NASP operating conditions. The information in these publications was used to estimate minimum and maximum jet Reynolds numbers needed to accomplish the required leading edge cooling, and to determine the parameters of the experiment. The details of this analysis are shown in Appendix A. One of the concerns for the NASP design is that of thermal stress due to large surface temperature gradients. Using a series of circular jets to cool the leading edge will cause a non-uniform temperature distribution and potentially large thermal stresses. Therefore it was decided to explore the feasibility of using a slot jet to cool the leading edge. The literature contains many investigations into circular jet heat transfer but few investigations of slot jet heat transfer. The first experiments will be done on circular jets impinging on a fiat plate and results compared to previously published data to establish the accuracy of the method. Subsequent experiments will be slot jets impinging on full scale models of the NASP leading edge. Table 1 shows the range of parameters to be explored. Next a preliminary design of the experiment was done. Previous papers which used a similar experimental technique were studied and elements of those experiments adapted to the jet impingement study. Trade-off studies were conducted to determine which design was the least expensive, easy to construct, and easy to use. Once the final design was settled, vendors were

  12. Fluid flow and heat convection studies for actively cooled airframes

    NASA Technical Reports Server (NTRS)

    Mills, A. F.

    1993-01-01

    This report details progress made on the jet impingement - liquid crystal - digital imaging experiment. With the design phase complete, the experiment is currently in the construction phase. In order to reach this phase two design related issues were resolved. The first issue was to determine NASP leading edge active cooling design parameters. Meetings were arranged with personnel at SAIC International, Torrance, CA in order to obtain recent publications that characterized expected leading edge heat fluxes as well as other details of NASP operating conditions. The information in these publications was used to estimate minimum and maximum jet Reynolds numbers needed to accomplish the required leading edge cooling, and to determine the parameters of the experiment. The details of this analysis are shown in Appendix A. One of the concerns for the NASP design is that of thermal stress due to large surface temperature gradients. Using a series of circular jets to cool the leading edge will cause a non-uniform temperature distribution and potentially large thermal stresses. Therefore it was decided to explore the feasibility of using a slot jet to cool the leading edge. The literature contains many investigations into circular jet heat transfer but few investigations of slot jet heat transfer. The first experiments will be done on circular jets impinging on a fiat plate and results compared to previously published data to establish the accuracy of the method. Subsequent experiments will be slot jets impinging on full scale models of the NASP leading edge. Table 1 shows the range of parameters to be explored. Next a preliminary design of the experiment was done. Previous papers which used a similar experimental technique were studied and elements of those experiments adapted to the jet impingement study. Trade-off studies were conducted to determine which design was the least expensive, easy to construct, and easy to use. Once the final design was settled, vendors were

  13. Characterization of cellulolytic activity from digestive fluids of Dissosteira carolina (Orthoptera: Acrididae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous screening of head-derived and gut fluid extracts of Carolina grasshoppers, Dissosteira carolina (L.), revealed relatively high activity against cellulase substrates when compared to other insect groups. In this work we report on the characterization and identification of enzymes involved i...

  14. Indices of free radical activity in the cerebrospinal fluid in motor neuron disease.

    PubMed Central

    Mitchell, J D; Jackson, M J; Pentland, B

    1987-01-01

    Indices of free-radical activity and lipid peroxidation were studied in cerebrospinal fluid samples obtained from 11 patients with motor neuron disease and 11 reference subjects. No differences were found between the two groups. The significance of this finding is discussed in relation to current views of the possible pathogenesis of this disease. PMID:3625217

  15. A Systematic Approach of Employing Quality by Design Principles: Risk Assessment and Design of Experiments to Demonstrate Process Understanding and Identify the Critical Process Parameters for Coating of the Ethylcellulose Pseudolatex Dispersion Using Non-Conventional Fluid Bed Process.

    PubMed

    Kothari, Bhaveshkumar H; Fahmy, Raafat; Claycamp, H Gregg; Moore, Christine M V; Chatterjee, Sharmista; Hoag, Stephen W

    2016-07-14

    The goal of this study was to utilize risk assessment techniques and statistical design of experiments (DoE) to gain process understanding and to identify critical process parameters for the manufacture of controlled release multiparticulate beads using a novel disk-jet fluid bed technology. The material attributes and process parameters were systematically assessed using the Ishikawa fish bone diagram and failure mode and effect analysis (FMEA) risk assessment methods. The high risk attributes identified by the FMEA analysis were further explored using resolution V fractional factorial design. To gain an understanding of the processing parameters, a resolution V fractional factorial study was conducted. Using knowledge gained from the resolution V study, a resolution IV fractional factorial study was conducted; the purpose of this IV study was to identify the critical process parameters (CPP) that impact the critical quality attributes and understand the influence of these parameters on film formation. For both studies, the microclimate, atomization pressure, inlet air volume, product temperature (during spraying and curing), curing time, and percent solids in the coating solutions were studied. The responses evaluated were percent agglomeration, percent fines, percent yield, bead aspect ratio, median particle size diameter (d50), assay, and drug release rate. Pyrobuttons® were used to record real-time temperature and humidity changes in the fluid bed. The risk assessment methods and process analytical tools helped to understand the novel disk-jet technology and to systematically develop models of the coating process parameters like process efficiency and the extent of curing during the coating process.

  16. Diurnal time-activity budgets of redheads (Aythya americana) wintering in seagrass beds and coastal ponds in Louisiana and Texas

    USGS Publications Warehouse

    Michot, T.C.; Woodin, M.C.; Adair, S.E.; Moser, E.B.

    2006-01-01

    Diurnal time-activity budgets were determined for wintering redheads (Aythya americana) from estuarine seagrass beds in Louisiana (Chandeleur Sound) and Texas (Laguna Madre) and from ponds adjacent to the Laguna Madre. Activities differed (p<0.0001) by location, month, and diurnal time period. Resting and feeding were the most frequent activities of redheads at the two estuarine sites, whereas drinking was almost nonexistent. Birds on ponds in Texas engaged most frequently in resting and drinking, but feeding was very infrequent. Redheads from the Louisiana estuarine site rested less than birds in Texas at either the Laguna Madre or freshwater ponds. Redheads in Louisiana fed more than birds in Texas; this was partially because of weather differences (colder temperatures in Louisiana), but the location effect was still significant even when we adjusted the model for weather effects. Redheads in Louisiana showed increased resting and decreased feeding as winter progressed, but redheads in Texas did not exhibit a seasonal pattern in either resting or feeding. In Louisiana, birds maintained a high level of feeding activity during the early morning throughout the winter, whereas afternoon feeding tapered off in mid- to late-winter. Texas birds showed a shift from morning feeding in early winter to afternoon feeding in late winter. Males and females at both Chandeleur Sound and Laguna Madre showed differences in their activities, but because the absolute difference seldom exceeded 2%, biological significance is questionable. Diurnal time-activity budgets of redheads on the wintering grounds are influenced by water salinities and the use of dietary fresh water, as well as by weather conditions, tides, and perhaps vegetation differences between sites. The opportunity to osmoregulate via dietary freshwater, vs. via nasal salt glands, may have a significant effect on behavioral allocations. ?? Springer 2006.

  17. Evaluation of activated sludge for biodegradation of propylene glycol as an aircraft deicing fluid.

    PubMed

    Delorit, Justin D; Racz, LeeAnn

    2014-04-01

    Aircraft deicing fluid used at airport facilities is often collected for treatment or disposal in order to prevent serious ecological threats to nearby surface waters. This study investigated lab scale degradation of propylene glycol, the active ingredient in a common aircraft deicing fluid, by way of a laboratory-scale sequencing batch reactor containing municipal waste water treatment facility activated sludge performing simultaneous organic carbon oxidation and nitrification. The ability of activated sludge to remove propylene glycol was evaluated by studying the biodegradation and sorption characteristics of propylene glycol in an activated sludge medium. The results indicate sorption may play a role in the fate of propylene glycol in AS, and the heterotrophic bacteria readily degrade this compound. Therefore, a field deployable bioreactor may be appropriate for use in flight line applications.

  18. Dissolution of bedded rock salt: A seismic profile across the active eastern margin of the Hutchinson Salt Member, central Kansas

    USGS Publications Warehouse

    Anderson, N.L.; Hopkins, J.; Martinez, A.; Knapp, R.W.; Macfarlane, P.A.; Watney, W.L.; Black, R.

    1994-01-01

    Since late Tertiary, bedded rock salt of the Permian Hutchinson Salt Member has been dissolved more-or-less continuously along its active eastern margin in central Kansas as a result of sustained contact with unconfined, undersaturated groundwater. The associated westward migration of the eastern margin has resulted in surface subsidence and the contemporaneous sedimentation of predominantly valley-filling Quarternary alluvium. In places, these alluvium deposits extend more than 25 km to the east of the present-day edge of the main body of contiguous rock salt. The margin could have receded this distance during the past several million years. From an environmental perspective, the continued leaching of the Hutchinson Salt is a major concern. This predominantly natural dissolution occurs in a broad zone across the central part of the State and adversely affects groundwater and surface-water quality as nonpoint source pollution. Significant surface subsidence occurs as well. Most of these subsidence features have formed gradually; others developed in a more catastrophic manner. The latter in particular pose real threats to roadways, railways, and buried oil and gas pipelines. In an effort to further clarify the process of natural salt dissolution in central Kansas and with the long-term goal of mitigating the adverse environmental affects of such leaching, the Kansas Geological Survey acquired a 4-km seismic profile across the eastern margin of the Hutchinson Salt in the Punkin Center area of central Kansas. The interpretation of these seismic data (and supporting surficial and borehole geologic control) is consistent with several hypotheses regarding the process and mechanisms of dissolution. More specifically these data support the theses that: 1. (1) Dissolution along the active eastern margin of the Hutchinson Salt Member was initiated during late Tertiary. Leaching has resulted in the steady westward migration of the eastern margin, surface subsidence, and the

  19. Seasonal composition and activity of sulfate-reducing prokaryotic communities in seagrass bed sediments

    EPA Science Inventory

    Sulfate-reducing prokaryotes (SRP) play a key role in the carbon and nutrient cycles of coastal marine, vegetated ecosystems, but the interactions of SRP communities with aquatic plants remain little studied. The abundance, activity, and community composition of SRP was studied i...

  20. Solar heated fluidized bed gasification system

    NASA Technical Reports Server (NTRS)

    Qader, S. A. (Inventor)

    1981-01-01

    A solar-powered fluidized bed gasification system for gasifying carbonaceous material is presented. The system includes a solar gasifier which is heated by fluidizing gas and steam. Energy to heat the gas and steam is supplied by a high heat capacity refractory honeycomb which surrounds the fluid bed reactor zone. The high heat capacity refractory honeycomb is heated by solar energy focused on the honeycomb by solar concentrator through solar window. The fluid bed reaction zone is also heated directly and uniformly by thermal contact of the high heat capacity ceramic honeycomb with the walls of the fluidized bed reactor. Provisions are also made for recovering and recycling catalysts used in the gasification process. Back-up furnace is provided for start-up procedures and for supplying heat to the fluid bed reaction zone when adequate supplies of solar energy are not available.

  1. The effect of bed defects on bedform generation - A new approach using the SPH simulation technique

    NASA Astrophysics Data System (ADS)

    Bartzke, Gerhard; Podszun, Lina; Huhn, Katrin

    2014-05-01

    Various researchers investigated the initiation of bed forms from a flat sediment bed in aquatic environments using analogue techniques, such as wave tanks or in situ field investigations. Nevertheless, this process particularly the role of major controlling factors is still not fully understood. Prior work has highlighted that the existence of bed defects has the potential to influence the erosion pattern at the surface of sediment beds. In such cases, artificial defects were manufactured in a flat bed and tested under various flow speeds, which resulted in the generation of various bed forms. As bed defects impinge on the in the interior of sediment beds, their effects on fluid flow conditions are difficult to quantify with analogue techniques. To investigate the fluid flow conditions occurring at the direct vicinity and in the interior of a sediment bed, a new 3D-SPH (Smooth Particle Hydrodynamics) numerical 'wave tank', as an alternative to the difficult task of in situ measurement, was used. The model geometry was chosen to mimic typical wave tank dimensions, i.e., X = 2.5 m, Y = 0.35 m, Z = 0.8 m. In order to generate a sediment bed 0.2 m in height, each grain (D50 = 4000 µm) was generated as a fixed particle. Afterwards, the numerical wave tank was flooded with fluid particles. A wave was generated using a vertical paddle accelerated to 0.8 m/s perpendicular to the bed. Six sets of experiments were undertaken with an increasing depth range of bed defects (0.04 - 0.2 m). High resolution flow conditions inside the bed defects as a function of the wave activity were constantly monitored. For estimation of sediment erosion, all measured flow speeds were compared to the Yalin (1972) curve describing transport initiation. The results showed that the fluid velocities in the bed defect increased with increasing bed defect size depth, which was accompanied by an increase of the flow velocities into the pore spaces along the flanks of the defect. With increasing wave

  2. Effects of adding fluids to solid foods on muscle activity and number of chewing cycles.

    PubMed

    van der Bilt, Andries; Engelen, Lina; Abbink, Jan; Pereira, Luciano J

    2007-06-01

    The production of a sufficient amount of saliva is indispensable for good chewing. In the present study, we examined the hypothesis that adding fluid to a food will facilitate the chewing process, especially for dry foods. The effect might be larger for subjects with relatively low salivary flow rates. Furthermore, adding fluids that contain mucins or alpha-amylase may have a larger facilitating effect on mastication than the addition of water alone. Twenty subjects chewed on melba toast, breakfast cake, carrot, peanut, and Gouda cheese. In addition, they chewed on these foods after different volumes of water, artificial saliva containing mucins, or a solution of alpha-amylase had been added. Muscle activity and number of chewing strokes until swallowing were measured. The salivary flow rates of the subjects were also determined. Adding fluid to the food significantly reduced the number of chewing cycles and total muscular work (i.e. the integrated surface electromyograpy of masseter and temporalis muscles measured bilaterally, summed for all chewing cycles) until swallowing for all foods, except carrot. The largest effects were observed for melba and cake, which are dry products requiring sufficient saliva to form a coherent bolus safe for swallowing. More facilitation of the chewing process was observed after adding fluid to breakfast cake for subjects with relatively low salivary flow rates. The type of fluid had no significant effect on the chewing process.

  3. Aqueous Volatiles in Hydrothermal fluids from the Main Endeavour Vent Field: Temporal Variability Following Earthquake Activity

    NASA Astrophysics Data System (ADS)

    Seewald, J. S.; Cruse, A. M.; Saccocia, P. J.

    2001-12-01

    Volatile species play a critical role in a broad spectrum of physical, chemical, and biological processes associated with hydrothermal circulation at oceanic spreading centers. Earthquake activity at the Main Endeavour vent field, northern Juan de Fuca Ridge in June 1999 [1] provided and opportunity to assess factors that regulate the flux of volatile species from the oceanic crust to the water column following a rapid change in subsurface reaction zone conditions. High temperature vent fluids were collected in gas-tight samplers at the Main Endeavour field in September 1999, approximately four months after the earthquakes, and again in July 2000, and were analyzed for the abundance of aqueous volatile and non-volatile species. Measured concentrations of aqueous H2, H2S, and CO2 increased substantially in September 1999 relative to pre-earthquake values [2,3], and subsequently decreased in July 2000, while aqueous Cl concentrations initially decreased in 1999 and subsequently increased in 2000. Concentrations of Cl in all fluids were depleted relative to seawater values. Aqueous CH4 and NH3 concentrations decreased in both the 1999 and 2000 samples relative to pre- earthquake values. Variations in Cl concentration of Endeavour fluids reflect varying degrees of phase separation under near critical temperature and pressure conditions. Because volatile species efficiently partition into the vapor phase, variations in their abundance as a function of Cl concentration can be used to constrain conditions of phase separation and fluid-rock interaction. For example, concentrations of volatile species that are not readily incorporated into minerals (CH4 and NH3) correlated weakly with Cl suggesting phase separation was occurring under supercritical conditions after the earthquake activity. In contrast, compositional data for fluids prior to the earthquakes indicate a strong negative correlation between these species and Cl suggesting phase separation under subcritical

  4. Emergent Structures in an Active Polar Fluid: Dynamics of Shape, Scattering, and Merger

    NASA Astrophysics Data System (ADS)

    Husain, Kabir; Rao, Madan

    2017-02-01

    Spatially localized defect structures emerge spontaneously in a hydrodynamic description of an active polar fluid comprising polar "actin" filaments and "myosin" motor proteins that (un)bind to filaments and exert active contractile stresses. These emergent defect structures are characterized by distinct textures and can be either static or mobile—we derive effective equations of motion for these "extended particles" and analyze their shape, kinetics, interactions, and scattering. Depending on the impact parameter and propulsion speed, these active defects undergo elastic scattering or merger. Our results are relevant for the dynamics of actomyosin-dense structures at the cell cortex, reconstituted actomyosin complexes, and 2D active colloidal gels.

  5. A non-intrusive fluid-wave actuator and sensor pair for the active control of fluid-borne vibrations in a pipe

    NASA Astrophysics Data System (ADS)

    Brennan, M. J.; Elliott, S. J.; Pinnington, R. J.

    1996-06-01

    This paper describes the design of a non-intrusive fluid-wave actuator and sensor pair for use in an active control system to control fluid-borne vibrations in pipework systems. Piping systems can be excited by sources such as pumps and compressors and vibrational energy can propagate both in the pipe wall and the fluid. The transducers developed in this paper are designed only for the control of the fluid-borne vibrational energy. A theoretical framework is developed that integrates the transducers into the pipe and couples them to the motion of the fluid inside the pipe. A hydraulic actuator driven with a magnetostrictive element and fitted to a water-filled perspex pipe has been designed and tested. The sensor was made from piezoelectric elements fitted around the outer circumference of the pipe. Experimental results show that the actuator is capable of suppressing a propagating fluid-wave, but in doing so it increases the vibration of the pipe-wall in the vicinity of the actuator. When the sensor is employed as an error sensor together with the actuator in the frequency range 10 - 1000 Hz, a reduction in the fluid-wave amplitude of around 20 dB is possible.

  6. The Impact of Ozone Treatment in Dynamic Bed Parameters on Changes in Biologically Active Substances of Juniper Berries.

    PubMed

    Brodowska, Agnieszka Joanna; Śmigielski, Krzysztof; Nowak, Agnieszka; Czyżowska, Agata; Otlewska, Anna

    2015-01-01

    The development of the parameters of ozone decontamination method assuring the least possible losses of biologically active substances (essential oils and polyphenols) and their activity in common juniper (Juniperus communis (L.)) berries was studied. Ozone treatment in dynamic bed was conducted 9 times. The process was conducted under different ozone concentrations (100.0; 130.0; 160.0 g O3/m3) and times (30, 60, 90 min). After each decontamination, the microbiological profile of the juniper berries was studied, and the contaminating microflora was identified. Next to the microbiological profile, the phenolic profile, as well as antioxidant activity of extracts and essential oils were determined. The total polyphenol content (TPC), composition of essential oils, free radical-scavenging capacity, total antioxidant capacity, ferric-reducing antioxidant power (FRAP), beta-carotene bleaching test (BCB) and LC-MS polyphenol analysis were carried out. The study reveals that during short ozone contact times, higher amounts of TPC, 15.47 and 12.91 mg CE/g of extract, for samples 100/30 and 130/30, respectively, were demonstrated. Whereas samples 100/60, 130/60, 100/90, and 160/90 exhibited the lowest amount of phenolics. The highest antioxidant activity was found in the methanol extract obtained from ozonated berries which exhibited the lowest IC50 in all the antioxidant assays, such as DPPH, FRAP, and BCB assays. Ozone treatment showed noteworthy potential and its usage in food manufacturing and as an alternative decontamination method should be considered.

  7. The Impact of Ozone Treatment in Dynamic Bed Parameters on Changes in Biologically Active Substances of Juniper Berries

    PubMed Central

    Brodowska, Agnieszka Joanna; Śmigielski, Krzysztof; Nowak, Agnieszka; Czyżowska, Agata; Otlewska, Anna

    2015-01-01

    The development of the parameters of ozone decontamination method assuring the least possible losses of biologically active substances (essential oils and polyphenols) and their activity in common juniper (Juniperus communis (L.)) berries was studied. Ozone treatment in dynamic bed was conducted 9 times. The process was conducted under different ozone concentrations (100.0; 130.0; 160.0 g O3/m3) and times (30, 60, 90 min). After each decontamination, the microbiological profile of the juniper berries was studied, and the contaminating microflora was identified. Next to the microbiological profile, the phenolic profile, as well as antioxidant activity of extracts and essential oils were determined. The total polyphenol content (TPC), composition of essential oils, free radical-scavenging capacity, total antioxidant capacity, ferric-reducing antioxidant power (FRAP), beta-carotene bleaching test (BCB) and LC-MS polyphenol analysis were carried out. The study reveals that during short ozone contact times, higher amounts of TPC, 15.47 and 12.91 mg CE/g of extract, for samples 100/30 and 130/30, respectively, were demonstrated. Whereas samples 100/60, 130/60, 100/90, and 160/90 exhibited the lowest amount of phenolics. The highest antioxidant activity was found in the methanol extract obtained from ozonated berries which exhibited the lowest IC50 in all the antioxidant assays, such as DPPH, FRAP, and BCB assays. Ozone treatment showed noteworthy potential and its usage in food manufacturing and as an alternative decontamination method should be considered. PMID:26659905

  8. Increased Brain Activation for Foot Movement During 70-Day 6 Deg Head-Down Bed Rest (HDBR): Evidence from Functional Magnetic Resonance Imaging (fMRI)

    NASA Technical Reports Server (NTRS)

    Yuan, P.; Koppelmans, V.; Cassady, K.; Cooke, K.; De Dios, Y. E.; Stepanyan, V.; Szecsy, D.; Gadd, N.; Wood, S. J.; Reuter-Lorenz, P. A.; Riascos-Castaneda, R.; Kofman, I.; Bloomberg, J. J.; Mulavara, A. P.; Seidler, R. D.

    2015-01-01

    Bed rest has been widely used as a simulation of weightlessness in studying the effects of microgravity exposure on human physiology and cognition. Changes in muscle function and functional mobility have been reported to be associated with bed rest. Understanding the effect of bed rest on neural control of movement would provide helpful information for spaceflight. In the current study, we evaluated how the brain activation for foot movement changed as a function of bed rest. Eighteen healthy men (aged 25 to 39 years) participated in this HDBR study. They remained continuously in the 6deg head-down tilt position for 70 days. Functional MRI was acquired during 1-Hz right foot tapping, and repeated at 7 time points: 12 days pre-, 8 days pre-, 7 days in-, 50 days in-, 70 days in-, 8 days post-, and 12 days post- HDBR. In all 7 sessions, we observed increased activation in the left motor cortex, right cerebellum and right occipital cortex during foot movement blocks compared to rest. Compared to the pre-HDBR baseline (1st and 2nd sessions), foot movement-induced activation in the left hippocampus increased during HDBR. This increase emerged in the 4th session, enlarged in the 5th session, and remained significant in the 6th and 7th sessions. Furthermore, increased activation relative to the baseline in left precuneus was observed in the 5th, 6th and 7th sessions. In addition, in comparison with baseline, increased activation in the left cerebellum was found in the 4th and 5th sessions, whereas increased activation in the right cerebellum was observed in the 4th, 6th and 7th sessions. No brain region exhibited decreased activation during bed rest compared to baseline. The increase of foot movement related brain activation during HDBR suggests that in a long-term head-down position, more neural control is needed to accomplish foot movements. This change required a couple of weeks to develop in HDBR (between 3rd and 4th sessions), and did not return to baseline even 12

  9. Immunosuppressive activity of human amniotic fluid of normal and abnormal pregnancies.

    PubMed

    Shohat, B; Faktor, J M

    1988-01-01

    Twenty specimens of amniotic fluid (AF) obtained between week 16 and 18 of gestation from normal pregnant women and six specimens from pregnant women in which trisomia of chromosome 21 was found were tested for immunosuppressive activity. Incubation of normal human donor lymphocytes with 0.2-1 mL of AF from normal pregnant women for one hour at 37 degrees C was sufficient for induction of significant inhibition of the ability of these cells to induce a local xenogeneic graft-versus-host reaction (GVHR) as well as inhibition of E and E-active rosette formation, the GVHR being the most sensitive test. On the other hand, amniotic fluid obtained from the six pregnant women in which trisomia of chromosome 21 was found showed no inhibitory activity in either the E or E-active rosette formation, nor in the local xenogeneic graft-versus-host reaction. AF from all the women tested was found to have no effect on phenotype expression of the lymphocytes, as tested by the monoclonal antibodies OKT4+ and OKT8+, nor on B-lymphocytes, as tested by surface immunoglobulins. No correlation was found between the alpha-fetoprotein levels in the sera of those women and the immunosuppressive activity. These findings indicate that genetic defects of the conceptus are not limited to the embryo but may affect the composition of immunosuppressive components present in normal amniotic fluid.

  10. Active 3-D microscaffold system with fluid perfusion for culturing in vitro neuronal networks.

    PubMed

    Rowe, Laura; Almasri, Mahmoud; Lee, Kil; Fogleman, Nick; Brewer, Gregory J; Nam, Yoonkey; Wheeler, Bruce C; Vukasinovic, Jelena; Glezer, Ari; Frazier, A Bruno

    2007-04-01

    This work demonstrated the design, fabrication, packaging, and characterization of an active microscaffold system with fluid perfusion/nutrient delivery functionalities for culturing in vitro neuronal networks from dissociated hippocampal rat pup neurons. The active microscaffold consisted of an 8 x 8 array of hollow, microfabricated, SU-8 towers (1.0 mm or 1.5 mm in height), with integrated, horizontal, SU-8 cross-members that connect adjacent towers, thus forming a 3-D grid that is conducive to branching, growth, and increased network formation of dissociated hippocampal neurons. Each microtower in the microscaffold system contained a hollow channel and multiple fluid ports for media delivery and perfusion of nutrients to the in vitro neuronal network growing within the microscaffold system. Additionally, there were two exposed Au electrodes on the outer wall of each microtower at varying heights (with insulated leads running within the microtower walls), which will later allow for integration of electrical stimulation/recording functionalities into the active microscaffold system. However, characterization of the stimulation/recording electrodes was not included in the scope of this paper. Design, fabrication, fluid packaging, and characterization of the active microscaffold system were performed. Furthermore, use of the active microscaffold system was demonstrated by culturing primary hippocampal embryonic rat pup neurons, and characterizing cell viability within the microscaffold system.

  11. Synovial fluid matrix metalloproteinase-2 and -9 activities in dogs suffering from joint disorders.

    PubMed

    Murakami, Kohei; Maeda, Shingo; Yonezawa, Tomohiro; Matsuki, Naoaki

    2016-07-01

    The activity of matrix metalloproteinase (MMP)-2 and MMP-9 in synovial fluids (SF) sampled from dogs with joint disorders was investigated by gelatin zymography and densitometry. Pro-MMP-2 showed similar activity levels in dogs with idiopathic polyarthritis (IPA; n=17) or canine rheumatoid arthritis (cRA; n=4), and healthy controls (n=10). However, dogs with cranial cruciate ligament rupture (CCLR; n=5) presented significantly higher pro-MMP-2 activity than IPA and healthy dogs. Meanwhile, dogs with IPA exhibited significantly higher activity of pro- and active MMP-9 than other groups. Activity levels in pro- and active MMP-9 in cRA and CCLR dogs were not significantly different from those in healthy controls. Different patterns of MMP-2 and MMP-9 activity may reflect the differences in the underlying pathological processes.

  12. Hydrothermal mineralogy and fluid inclusions chemistry to understand the roots of active geothermal systems

    NASA Astrophysics Data System (ADS)

    Chambefort, I. S.; Dilles, J. H.; Heinrich, C.

    2013-12-01

    An integrated study to link magmatic textures, magmatic mineral compositions, hydrothermal alteration zoning, hydrothermal mineral chemistry, and fluid inclusion compositions has been undertaken to link an intrusive complex and its degassing alteration halo with their surface equivalent in an active geothermal system. Ngatamariki geothermal system, New Zealand, presents a unique feature in the Taupo Volcanic Zone (TVZ). Drilling intercepted an intrusive complex with a high temperature alteration halo similarly to what is observed in magmatic-derived ore deposits. Thus it presents the perfect opportunity to study the magmatic-hydrothermal transition of the TVZ by characterizing the nature of the deep magmatic fluids link to the heat source of the world known geothermal fields. The record of magmatic-hydrothermal fluid-rock interactions preserved at Ngatamariki may be analogous of processes presently occurring at depth beneath TVZ geothermal systems. The intrusive complex consists of over 5 km3 of tonalite, diorite, basalt and aplitic dykes. Evidence of undercooling subsolidus magmatic textures such as myrmekite and skeletal overgrowth are commonly observed and often linked to volatile loss. The fluids released during the crystallization of the intrusive complex are interpreted to be at the origin of the surrounding high temperature alteration halo. Advanced argillic to potassic alteration and high temperature acidic assemblage is associated with high-temperature quartz veining at depth and vuggy silica at the paleo-surface. Major element compositions of the white micas associated with the high temperature halo show a transition from, muscovite to phengite, muscovitic illite away from the intrusion, with a transition to pyrophyllite and/ or topaz, and andalusite characteristic of more acidic conditions. Abundant high-density (up to 59 wt% NaCl eq and homogenization temperatures of 550 degree Celsius and above) coexist with low-density vapor fluid inclusions. This

  13. Physiology Of Prolonged Bed Rest

    NASA Technical Reports Server (NTRS)

    Greenleaf, John E.

    1991-01-01

    Report describes physiological effects of prolonged bed rest. Rest for periods of 24 hours or longer deconditions body to some extent; healing proceeds simultaneously with deconditioning. Report provides details on shifts in fluid electrolytes and loss of lean body mass, which comprises everything in body besides fat - that is, water, muscle, and bone. Based on published research.

  14. The Local Complement Activation on Vascular Bed of Patients with Systemic Sclerosis: A Hypothesis-Generating Study

    PubMed Central

    Scambi, Cinzia; Ugolini, Sara; Jokiranta, T. Sakari; De Franceschi, Lucia; Bortolami, Oscar; La Verde, Valentina; Guarini, Patrizia; Caramaschi, Paola; Ravagnani, Viviana; Martignoni, Guido; Colato, Chiara; Pedron, Serena; Benedetti, Fabio; Sorio, Marco; Poli, Fabio; Biasi, Domenico

    2015-01-01

    Objective The role of complement system in the pathogenesis of systemic sclerosis (SSc) has been debated during the last decade but an evident implication in this disease has never been found. We carried out an explorative study on SSc patients to evaluate the expression of soluble and local C5b-9 complement complex and its relation with a complement regulator, the Membrane Cofactor Protein (MCP, CD46) on skin vascular bed as target distinctive of SSc disease. We also analyzed two polymorphic variants in the complement activation gene cluster involving the MCP region. Methods C5b-9 plasma levels of SSc patients and healthy subjects were analyzed by ELISA assay. Archival skin biopsies of SSc patients and controls were subjected to immunofluorescence analysis to detect C5b-9 and MCP on vascular endothelial cells. The expression of MCP was validated by immunoblot analysis with specific antibody. Polymorphic variants in the MCP gene promoter were tested by a quantitative PCR technique-based allelic discrimination method. Results Even though circulating levels of C5b-9 did not differ between SSc and controls, C5b-9 deposition was detected in skin biopsies of SSc patients but not in healthy subjects. MCP was significantly lower in skin vessels of SSc patients than in healthy controls and was associated with the over-expression of two polymorphic variants in the MCP gene promoter, which has been related to more aggressive phenotypes in other immune-mediated diseases. Conclusions Our results firsty document the local complement activation with an abnormal expression of MCP in skin vessels of SSc patients, suggesting that a subset of SSc patients might be exposed to more severe organ complications and clinical evolution due to abnormal local complement activation. PMID:25658605

  15. Ethanol-induced anxiolysis and neuronal activation in the amygdala and bed nucleus of the stria terminalis

    PubMed Central

    Sharko, Amanda C.; Kaigler, Kris F.; Fadel, Jim R.; Wilson, Marlene A.

    2016-01-01

    High rates of comorbidity for anxiety and alcohol-use disorders suggest a causal relationship between these conditions. Previous work demonstrates basal anxiety levels in outbred Long-Evans rats correlate with differences in voluntary ethanol consumption and that amygdalar Neuropeptide Y (NPY) systems may play a role in this relationship. The present work explores the possibility that differences in sensitivity to ethanol’s anxiolytic effects contribute to differential ethanol self-administration in these animals and examines the potential role of central and peripheral NPY in mediating this relationship. Animals were first exposed to the elevated plus maze (EPM) to assess individual differences in anxiety-like behaviors and levels of circulating NPY and corticosterone (CORT). Rats were then tested for anxiety-like behavior in the light-dark box (LD box) following acute ethanol treatment (1 g/kg; intraperitoneally [i.p.]), and neuronal activation in the amygdala and bed nucleus of the stria terminalis (BNST) was assessed using Fos immunohistochemistry. EPM exposure increased plasma CORT levels without altering plasma NPY levels. Acute ethanol treatment significantly increased light-dark transitions and latency to re-enter the light arena, but no differences were seen between high- and low-anxiety groups and no correlations were found between anxiety-like behaviors in the EPM and LD box. Acute ethanol treatment significantly increased Fos immunoreactivity in the BNST and the central amygdala. Although NPY neurons were not significantly activated following ethanol exposure, in saline-treated animals lower levels of anxiety-like behavior in the LD box (more time in the light arena and more transitions) were correlated with higher NPY-positive cell density in the central amygdala. Our results suggest that activation of the CeA and BNST are involved in the behavioral expression of ethanol-induced anxiolysis, and that differences in basal anxiety state may be

  16. Ethanol-induced anxiolysis and neuronal activation in the amygdala and bed nucleus of the stria terminalis.

    PubMed

    Sharko, Amanda C; Kaigler, Kris F; Fadel, Jim R; Wilson, Marlene A

    2016-02-01

    High rates of comorbidity for anxiety and alcohol-use disorders suggest a causal relationship between these conditions. Previous work demonstrates basal anxiety levels in outbred Long-Evans rats correlate with differences in voluntary ethanol consumption and that amygdalar Neuropeptide Y (NPY) systems may play a role in this relationship. The present work explores the possibility that differences in sensitivity to ethanol's anxiolytic effects contribute to differential ethanol self-administration in these animals and examines the potential role of central and peripheral NPY in mediating this relationship. Animals were first exposed to the elevated plus maze (EPM) to assess individual differences in anxiety-like behaviors and levels of circulating NPY and corticosterone (CORT). Rats were then tested for anxiety-like behavior in the light-dark box (LD box) following acute ethanol treatment (1 g/kg; intraperitoneally [i.p.]), and neuronal activation in the amygdala and bed nucleus of the stria terminalis (BNST) was assessed using Fos immunohistochemistry. EPM exposure increased plasma CORT levels without altering plasma NPY levels. Acute ethanol treatment significantly increased light-dark transitions and latency to re-enter the light arena, but no differences were seen between high- and low-anxiety groups and no correlations were found between anxiety-like behaviors in the EPM and LD box. Acute ethanol treatment significantly increased Fos immunoreactivity in the BNST and the central amygdala. Although NPY neurons were not significantly activated following ethanol exposure, in saline-treated animals lower levels of anxiety-like behavior in the LD box (more time in the light arena and more transitions) were correlated with higher NPY-positive cell density in the central amygdala. Our results suggest that activation of the CeA and BNST are involved in the behavioral expression of ethanol-induced anxiolysis, and that differences in basal anxiety state may be correlated

  17. Recovery comparisons--hot nitrogen Vs steam regeneration of toxic dichloromethane from activated carbon beds in oil sands process.

    PubMed

    Ramalingam, Shivaji G; Pré, Pascaline; Giraudet, Sylvain; Le Coq, Laurence; Le Cloirec, Pierre; Baudouin, Olivier; Déchelotte, Stéphane

    2012-02-29

    The regeneration experiments of dichloromethane from activated carbon bed had been carried out by both hot nitrogen and steam to evaluate the regeneration performance and the operating cost of the regeneration step. Factorial Experimental Design (FED) tool had been implemented to optimize the temperature of nitrogen and the superficial velocity of the nitrogen to achieve maximum regeneration at an optimized operating cost. All the experimental results of adsorption step, hot nitrogen and steam regeneration step had been validated by the simulation model PROSIM. The average error percentage between the simulation and experiment based on the mass of adsorption of dichloromethane was 2.6%. The average error percentages between the simulations and experiments based on the mass of dichloromethane regenerated by nitrogen regeneration and steam regeneration were 3 and 12%, respectively. From the experiments, it had been shown that both the hot nitrogen and steam regeneration had regenerated 84% of dichloromethane. But the choice of hot nitrogen or steam regeneration depends on the regeneration time, operating costs, and purity of dichloromethane regenerated. A thorough investigation had been made about the advantages and limitations of both the hot nitrogen and steam regeneration of dichloromethane.

  18. Degradation of p-nitrophenol in aqueous solution by microwave assisted oxidation process through a granular activated carbon fixed bed.

    PubMed

    Bo, Longli; Quan, Xie; Chen, Shuo; Zhao, Huimin; Zhao, Yazhi

    2006-09-01

    A microwave (MW) assisted oxidation process was investigated for degradation of p-nitrophenol (PNP) from aqueous solution. The process consisted of a granular activated carbon (GAC) fixed bed reactor, a MW source, solution and air supply system, and a heat exchanger. The process was operated in continuous flow mode. Air was applied for oxygen supply. GAC acted as a MW energy absorption material as well as the catalyst for PNP degradation. MW power, air flow, GAC dose, and influent flow proved to be major factors which influenced PNP degradation. The results showed that PNP was degraded effectively by this new process. Under a given condition (PNP concentration 1330mg/L, MW power 500 W, influent flow 6.4 mL/min, air flow 100 mL/min), PNP removed 90%, corresponding to 80% of TOC removal. The pathway of PNP degradation was deduced based on GC-MS identification of course products. PNP experienced sequential oxidation steps and mineralized ultimately. Nitro-group of PNP converted to nitrite and nitrate. Biodegradability of the solution was improved apparently after treatment by MW assisted oxidation process, which benefit to further treatment of the solution using biochemical method.

  19. A compact process for treating oilfield wastewater by combining hydrolysis acidification, moving bed biofilm, ozonation and biologically activated carbon techniques.

    PubMed

    Zheng, Tao

    2016-01-01

    A lab-scale hybrid system integrating a hybrid hydrolysis acidification (HA) reactor, a moving bed biofilm reactor (MBBR) and an ozonation-biologically activated carbon (O3-BAC) unit was used in the treatment of heavy oil wastewater with high chemical oxygen demand (COD) and low biodegradability. The effects of hydraulic retention time and ozonation time were investigated. The results show that under the optimal conditions, the effluent concentrations of COD, oil and ammonia were 48, 1.3 and 3.5 mg/L, respectively, corresponding to total removal efficiencies of 95.8%, 98.9% and 94.4%, respectively. The effluent could meet the grade I as required by the national discharge standard of China. The HA process remarkably improved the biodegradability of the wastewater, while the MBBR process played an important role in degrading COD. The ozonation process further enhanced the biodegradability of the MBBR effluent, and finally, deep treatment was completed in the BAC reactor. This work demonstrates that the hybrid HA/MBBR/O3-BAC system has the potential to be used for the treatment of high-strength oilfield wastewater.

  20. Nepenthesin protease activity indicates digestive fluid dynamics in carnivorous nepenthes plants.

    PubMed

    Buch, Franziska; Kaman, Wendy E; Bikker, Floris J; Yilamujiang, Ayufu; Mithöfer, Axel

    2015-01-01

    Carnivorous plants use different morphological features to attract, trap and digest prey, mainly insects. Plants from the genus Nepenthes possess specialized leaves called pitchers that function as pitfall-traps. These pitchers are filled with a digestive fluid that is generated by the plants themselves. In order to digest caught prey in their pitchers, Nepenthes plants produce various hydrolytic enzymes including aspartic proteases, nepenthesins (Nep). Knowledge about the generation and induction of these proteases is limited. Here, by employing a FRET (fluorescent resonance energy transfer)-based technique that uses a synthetic fluorescent substrate an easy and rapid detection of protease activities in the digestive fluids of various Nepenthes species was feasible. Biochemical studies and the heterologously expressed Nep II from Nepenthes mirabilis proved that the proteolytic activity relied on aspartic proteases, however an acid-mediated auto-activation mechanism was necessary. Employing the FRET-based approach, the induction and dynamics of nepenthesin in the digestive pitcher fluid of various Nepenthes plants could be studied directly with insect (Drosophila melanogaster) prey or plant material. Moreover, we observed that proteolytic activity was induced by the phytohormone jasmonic acid but not by salicylic acid suggesting that jasmonate-dependent signaling pathways are involved in plant carnivory.

  1. Nepenthesin Protease Activity Indicates Digestive Fluid Dynamics in Carnivorous Nepenthes Plants

    PubMed Central

    Buch, Franziska; Kaman, Wendy E.; Bikker, Floris J.; Yilamujiang, Ayufu; Mithöfer, Axel

    2015-01-01

    Carnivorous plants use different morphological features to attract, trap and digest prey, mainly insects. Plants from the genus Nepenthes possess specialized leaves called pitchers that function as pitfall-traps. These pitchers are filled with a digestive fluid that is generated by the plants themselves. In order to digest caught prey in their pitchers, Nepenthes plants produce various hydrolytic enzymes including aspartic proteases, nepenthesins (Nep). Knowledge about the generation and induction of these proteases is limited. Here, by employing a FRET (fluorescent resonance energy transfer)-based technique that uses a synthetic fluorescent substrate an easy and rapid detection of protease activities in the digestive fluids of various Nepenthes species was feasible. Biochemical studies and the heterologously expressed Nep II from Nepenthes mirabilis proved that the proteolytic activity relied on aspartic proteases, however an acid-mediated auto-activation mechanism was necessary. Employing the FRET-based approach, the induction and dynamics of nepenthesin in the digestive pitcher fluid of various Nepenthes plants could be studied directly with insect (Drosophila melanogaster) prey or plant material. Moreover, we observed that proteolytic activity was induced by the phytohormone jasmonic acid but not by salicylic acid suggesting that jasmonate-dependent signaling pathways are involved in plant carnivory. PMID:25750992

  2. Inflammatory synovial fluid microenvironment drives primary human chondrocytes to actively take part in inflammatory joint diseases.

    PubMed

    Röhner, Eric; Matziolis, Georg; Perka, Carsten; Füchtmeier, Bernd; Gaber, Timo; Burmester, Gerd-Rüdiger; Buttgereit, Frank; Hoff, Paula

    2012-06-01

    The role of human chondrocytes in the pathogenesis of cartilage degradation in rheumatic joint diseases has presently gained increasing interest. An active chondrocyte participation in local inflammation may play a role in the initiation and progression of inflammatory joint diseases and in a disruption of cartilage repair mechanisms resulting in cartilage degradation. In the present study, we hypothesized that inflammatory synovial fluid triggers human chondrocytes to actively take part in inflammatory processes in rheumatic joint diseases. Primary human chondrocytes were incubated in synovial fluids gained from patients with rheumatoid arthritis, psoriasis arthritis and reactive arthritis. The detection of vital cell numbers was determined by using Casy Cell Counter System. Apoptosis was measured by Annexin-V and 7AAD staining. Cytokine and chemokine secretion was determined by a multiplex suspension array. Detection of vital cells showed a highly significant decrease in chondrocyte numbers. Flow cytometry demonstrated a significant increase in apoptotic chondrocytes after the incubation. An active secretion of cytokines such as MCP-1 and MIF by chondrocytes was observed. The inflammatory synovial fluid microenvironment mediates apoptosis and cell death of chondrocytes. Moreover, in terms of cytokine secretion, it also induces an active participation of chondrocytes in ongoing inflammation.

  3. Serum and blister fluid pharmacokinetics and bactericidal activities of ampicillin-sulbactam, cefotetan, cefoxitin, ceftizoxime, and ticarcillin-clavulanate.

    PubMed

    Jaresko, G S; Barriere, S L; Johnson, B L

    1992-10-01

    Ampicillin-sulbactam, ticarcillin-clavulanate, cefoxitin, cefotetan, and ceftizoxime are promoted for the treatment of mixed aerobic-anaerobic bacterial infections. Their activities have been compared in vitro but not in vivo. In order to assess the in vivo activities of these agents in serum and interstitial fluid, we administered single, intravenous doses of these antimicrobial agents to healthy subjects. Concentrations of the antimicrobial agents in serum and suction-induced blister fluid and bactericidal activity were measured by high-pressure liquid chromatography and the standard methodology of the National Committee for Clinical Laboratory Standards, respectively. The organisms used for bactericidal activity tests were one isolate each of Staphylococcus aureus, Klebsiella pneumoniae, and Bacteroides fragilis. Pharmacokinetic parameters in serum and blister fluid were similar to those derived in other investigations. Of note were the high and prolonged concentrations of ticarcillin and cefotetan in blister fluid, despite high-level serum protein binding. The bactericidal activities in serum and blister fluid reflected the relative in vitro activities and kinetic dispositions of the various antimicrobial agents except for the bactericidal activity of cefotetan, which was substantially lower in blister fluid than serum, despite a blister fluid:serum area under the concentration-time curve ratio of 1.5. Similarly, the activity of ticarcillin-clavulanate in blister fluid was also substantially less than would have been predicted by the blister fluid:serum ratio of the area under the concentration-time curve of 1.1, possibly because of the low concentrations of clavulanate in blister fluid. The rankings of the in vivo bactericidal activities of the five drugs were as follows: for S. aureus, ampicillin-sulbactam > ticarcillin-clavulanate > ceftizoxime > cefoxitin > cefotetan; for K. pneumoniae, ceftizoxime > cefotetan > ampicillin-sulbactam = ticarcillin

  4. Effect of a fluid layer on the sound radiation of a plate and its active control

    NASA Astrophysics Data System (ADS)

    Sun, Yao; Pan, Jie; Yang, Tiejun

    2015-11-01

    In this paper, a baffled plate facing a layer of fluid is used to investigate the effects of the radiating environment on the plate's sound radiation and its active control. By varying the thickness of the fluid layer, different radiation environments are presented to the plate, resulting in a variation in the efficiencies and shapes of the radiation modes of the plate. As the design of feed-forward control of the radiated sound power and of feedback control of the vibration velocity or volume velocity is limited by the properties of the secondary control path (an open-loop frequency response function), the performance of the control system may be deteriorated if a controller optimally designed for one radiation environment is used for a different environment. The effects of radiation environment on the properties of the secondary control path and performance of active control are investigated.

  5. Biocatalytic synthesis of acrylates in supercritical fluids: tuning enzyme activity by changing pressure.

    PubMed Central

    Kamat, S V; Iwaskewycz, B; Beckman, E J; Russell, A J

    1993-01-01

    Supercritical fluids are a unique class of nonaqueous media in which biocatalytic reactions can occur. The physical properties of supercritical fluids, which include gas-like diffusivities and liquid-like densities, can be predictably controlled with changing pressure. This paper describes how adjustment of pressure, with the subsequent predictable changes of the dielectric constant and Hildebrand solubility parameter for fluoroform, ethane, sulfur hexafluoride, and propane, can be used to manipulate the activity of lipase in the transesterification of methylmethacrylate with 2-ethyl-1-hexanol. Of particular interest is that the dielectric constant of supercritical fluoroform can be tuned from approximately 1 to 8, merely by increasing pressure from 850 to 4000 psi (from 5.9 to 28 MPa). The possibility now exists to predictably alter both the selectivity and the activity of a biocatalyst merely by changing pressure. Images Fig. 6 PMID:8464910

  6. Biochemical and hormonal changes in endurance trained volunteers during and after exposure to bed rest and chronic hyperhydration

    NASA Astrophysics Data System (ADS)

    Zorbas, Y. G.; Naexu, K. A.; Yaroshenko, Y. N.

    2000-04-01

    The objective of this investigation was to assess the effect of a daily intake of fluid and salt supplementation on biochemical and hormonal changes in endurance trained volunteers aged 19-24 yrs during 30-day bed rest and during 15 days of post bed rest period. The studies were performed on 30 long distance runners aged 19-24 yrs who had a peak oxygen uptake of 66 ml/kg/min and had taken 14.5 km/day on average prior to their participation in the study. The volunteers were divided into three groups: the volunteers in the first group were under normal ambulatory conditions (control subjects); the second group subjected to bed rest alone unsupplemented (bed rested volunteers); the third group was submitted to bed rest and consumed daily 30 ml water/kg bodyweight and 0.1 g of sodium chloride (NaCl)/kg body weight (supplemented bed rested volunteers). The second and third groups of volunteers were kept under a rigorous bed rest regime for 30 days. During the pre bed rest period of 15 days, during the bed rest period of 30 days and during the post bed rest period of 15 days cyclic adenosine monophosphate, cyclic guanosine monophosphate, prostaglandins of pressor, prostaglandins depressor groups, renin activity in plasma and aldosterone in plasma and in urine were determined. We found that in bed rested volunteers without fluid and salt supplementation intake plasma renin activity and aldosterone in plasma and urine continued to increase during the bed rest period as plasma volume decreased. Moreover, in this group, cyclic nucleotides measured as an indicator of adrenosympathetic system activity increased and prostaglandins as local vasoactive substances decreased during the bed rest period. These variables returned toward the baselines in the post bed rest period as plasma volume deficit was restituted. On the other hand, the hormonal levels in the other two groups remained rather constant during the experimental period. We concluded that daily intake of fluid and salt

  7. The effect of sitting and calf activity on leg fluid and snoring.

    PubMed

    Singh, Bhajan; Yadollahi, Azadeh; Lyons, Owen; Alshaer, Hisham; Bradley, T Douglas

    2017-02-16

    Prolonged sitting may promote leg fluid retention that redistributes to the neck during sleep and contributes to snoring. This could be attenuated by calf activity while sitting. In 16 healthy non-obese subjects we measured leg fluid volume (LFV) below the knees using bioelectrical impedance while sitting for 4h, snoring using a portable BresoDx™ device, and Mallampati grade. Using a double cross-over study design, subjects were randomized to one of two arms and crossed-over one week later: control arm - no calf exercise while sitting; intervention arm - calf contraction against a pedal resistance while sitting. The effects of sitting±calf activity on LFV and snoring were compared. We found that LFV increased by 216±101.0ml (p<0.0001) after sitting. Calf activity while sitting attenuated LFV by 53.8ml (p<0.0001) and, in all five subjects with severe upper airway narrowing (Mallampati grade IV), reduced snoring duration (from 357±132.9 to 116.2±72.1s/h, p=0.02) suggesting reduced overnight rostral fluid shift to the neck.

  8. Treatment bed microbiological control

    NASA Technical Reports Server (NTRS)

    Janauer, Gilbert E.; Fitzpatrick, Timothy W.; Kril, Michael B.; Wilber, Georgia A.; Sauer, Richard L.

    1987-01-01

    The effects of microbial fouling on treatment bed (TB) performance are being studied. Fouling of activated carbon (AC) and ion exchange resins (IEX) by live and devitalized bacteria can cause decreased capacity for selected sorbates with AC and IEX TB. More data are needed on organic species removal in the trace region of solute sorption isotherms. TB colonization was prevented by nonclassical chemical disinfectant compositions (quaternary ammonium resins) applied in suitable configurations. Recently, the protection of carbon beds via direct disinfectant impregnation has shown promise. Effects (of impregnation) upon bed sorption/removal characteristics are to be studied with representative contaminants. The potential need to remove solutes added or produced during water disinfection and/or TB microbiological control must be investigated.

  9. Inter-bed fluid triggered slope failures of the Kaoping Canyon upstream area: Results from memorial R/V Ocean Researcher 5

    NASA Astrophysics Data System (ADS)

    Yeh, Yi-Ching; Shen, Tsung-Fu; Liu, Shao-Yung; Yu, Pai-Sen

    2015-04-01

    As a major pathway of the sediment transportation, the submarine canyons sculpture the seafloor then deposit sediments at the deep ocean. The submarine canyons could be classified to two categories: erosive or deposition based on geological environment or fluid flow down to the canyon. The erosive canyons often 'attack' the levee which may result in submarine landslides or mass transportations due to slope failure. Once slope failure occurs at geological weakness area such as gas hydrate dissociation zone, giant mass slumping will be triggered. These kinds of mass transportations will further develop turbidity current or hyperpycnal flow, which could damage the submarine cables or pipes. The giant mass transportation even triggers devastated tsunami. In this study, a latest swath bathymetric map was compiled by comprising seven cruises between December, 2012 and March 2013. The result shows that regressive erosion may take a place north of 500 meters contour (gas hydrate dissociation region), southwest off Taiwan. Moreover, high resolution seismic image (acquired by Edgetech SB-424 sub-bottom profiler) show that gas rich sediments co-exist with submarine landslide deposits in the edge of the upstream of Kaoping submarine canyon. It implies that slope failures in the study area might be caused by weaken sediment collapse.

  10. Kinetic arrest, dynamical transitions, and activated relaxation in dense fluids of attractive nonspherical colloids

    NASA Astrophysics Data System (ADS)

    Zhang, Rui; Schweizer, Kenneth S.

    2011-06-01

    The coupled translation-rotation activated dynamics in dense suspensions of attractive homogeneous and Janus uniaxial dicolloids are studied using microscopic statistical mechanical theory. Multiple kinetic arrest transitions and reentrant phenomena are predicted that are associated with fluid, gel, repulsive glass, attractive glass, plastic glass, and novel glass-gel states. The activated relaxation rate is a nonuniversal nonmonotonic function of attraction strength at high volume fractions due to the consequences of a change of the transient localization mechanism from caging to physical bonding.

  11. Effects of spatial variation of skull and cerebrospinal fluid layers on optical mapping of brain activities

    NASA Astrophysics Data System (ADS)

    Wang, Shuping; Shibahara, Nanae; Kuramashi, Daishi; Okawa, Shinpei; Kakuta, Naoto; Okada, Eiji; Maki, Atsushi; Yamada, Yukio

    2010-07-01

    In order to investigate the effects of anatomical variation in human heads on the optical mapping of brain activity, we perform simulations of optical mapping by solving the photon diffusion equation for layered-models simulating human heads using the finite element method (FEM). Particularly, the effects of the spatial variations in the thicknesses of the skull and cerebrospinal fluid (CSF) layers on mapping images are investigated. Mapping images of single active regions in the gray matter layer are affected by the spatial variations in the skull and CSF layer thicknesses, although the effects are smaller than those of the positions of the active region relative to the data points. The increase in the skull thickness decreases the sensitivity of the images to active regions, while the increase in the CSF layer thickness increases the sensitivity in general. The images of multiple active regions are also influenced by their positions relative to the data points and by their depths from the skin surface.

  12. RADIOACTIVE DEMONSTRATIONS OF FLUIDIZED BED STEAM REFORMING WITH ACUTAL HANFORD LOW ACTIVITY WASTES VERIFYING FBSR AS A SUPPLEMENTARY TREATMENT

    SciTech Connect

    Jantzen, C.; Crawford, C.; Burket, P.; Bannochie, C.; Daniel, G.; Nash, C.; Cozzi, A.; Herman, C.

    2012-01-12

    The U.S. Department of Energy's Office of River Protection is responsible for the retrieval, treatment, immobilization, and disposal of Hanford's tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level waste (HLW) and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the cleanup mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA). Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. Fluidized Bed Steam Reforming (FBSR) is one of the supplementary treatments being considered. FBSR offers a moderate temperature (700-750 C) continuous method by which LAW and other secondary wastes can be processed irrespective of whether they contain organics, nitrates/nitrites, sulfates/sulfides, chlorides, fluorides, and/or radio-nuclides like I-129 and Tc-99. Radioactive testing of Savannah River LAW (Tank 50) shimmed to resemble Hanford LAW and actual Hanford LAW (SX-105 and AN-103) have produced a ceramic (mineral) waste form which is the same as the non-radioactive waste simulants tested at the engineering scale. The radioactive testing demonstrated that the FBSR process can retain the volatile radioactive components that cannot be contained at vitrification temperatures. The radioactive and nonradioactive mineral waste forms that were produced by co-processing waste with kaolin clay in an FBSR process are shown to be as durable as LAW glass.

  13. Combined fluidized bed retort and combustor

    DOEpatents

    Shang, Jer-Yu; Notestein, John E.; Mei, Joseph S.; Zeng, Li-Wen

    1984-01-01

    The present invention is directed to a combined fluidized bed retorting and combustion system particularly useful for extracting energy values from oil shale. The oil-shale retort and combustor are disposed side-by-side and in registry with one another through passageways in a partition therebetween. The passageways in the partition are submerged below the top of the respective fluid beds to preclude admixing or the product gases from the two chambers. The solid oil shale or bed material is transported through the chambers by inclining or slanting the fluidizing medium distributor so that the solid bed material, when fluidized, moves in the direction of the downward slope of the distributor.

  14. Conceptual design of ECLSS microgravity test beds

    NASA Technical Reports Server (NTRS)

    Kolodney, Matt; Dall-Bauman, Liese

    1992-01-01

    Conceptual designs were prepared for Space Station Freedom ECLSS test beds for both the Air Revitalization Subsystem (ARS) and the Water Recovery and Management Subsystem (WRMS), which will allow extended testing of equipment under microgravity conditions. The separate designs for the ARS and the WRMS include storage tanks, plumbing, and limited instrumentation that would be expected to be common to all air or water treatment equipment of interest. The beds are designed to recycle process fluids to the greatest extent possible, thus minimizing the spacecraft/test bed interface requirements. Schematic diagrams of both the ARS and the WRMS test beds are included.

  15. Plasma volume restoration with salt tablets and water after bed rest prevents orthostatic hypotension and changes in supine hemodynamic and endocrine variables.

    PubMed

    Waters, Wendy W; Platts, Steven H; Mitchell, Brett M; Whitson, Peggy A; Meck, Janice V

    2005-02-01

    Head-down bed rest changes the values of many cardiovascular and endocrine variables and also elicits significant hypovolemia. Because previous studies had not controlled for hypovolemia, it is unknown whether the reported changes were primary effects of bed rest or secondary effects of bed rest-induced hypovolemia. We hypothesized that restoring plasma volume with salt tablets and water after 12 days of head-down bed rest would result in an absence of hemodynamic and endocrine changes and a reduced incidence of orthostatic hypotension. In 10 men, we measured changes from pre-bed-rest to post-bed-rest in venous and arterial pressures; heart rate; stroke volume; cardiac output; vascular resistance; plasma norepinephrine, epinephrine, vasopressin, renin activity (PRA), and aldosterone responses to different tilt levels (0 degrees, -10 degrees, 20 degrees, 30 degrees, and 70 degrees); and plasma volume and platelet alpha2- and lymphocyte beta2-adrenoreceptor densities and affinities (0 degrees tilt only). Fluid loading at the end of bed rest restored plasma volume and resulted in the absence of post-bed-rest orthostatic hypotension and changes in supine hemodynamic and endocrine variables. Fluid loading did not prevent post-bed-rest increases in beta2-adrenoreceptor density or decreases in the aldosterone-to-PRA ratio (P = 0.05 for each). Heart rate, epinephrine, and PRA responses to upright tilt after bed rest were increased (P < 0.05), despite the fluid load. These results suggest that incidents of orthostatic hypotension and many of the changes in supine hemodynamic and endocrine variables in volume-depleted bed-rested subjects occur secondarily to the hypovolemia. Despite normovolemia after bed rest, beta2-adrenoreceptors were upregulated, and heart rate, epinephrine, and PRA responses to tilt were augmented, indicating that these changes are independent of volume depletion.

  16. Staged cascade fluidized bed combustor

    DOEpatents

    Cannon, Joseph N.; De Lucia, David E.; Jackson, William M.; Porter, James H.

    1984-01-01

    A fluid bed combustor comprising a plurality of fluidized bed stages interconnected by downcomers providing controlled solids transfer from stage to stage. Each stage is formed from a number of heat transfer tubes carried by a multiapertured web which passes fluidizing air to upper stages. The combustor cross section is tapered inwardly from the middle towards the top and bottom ends. Sorbent materials, as well as non-volatile solid fuels, are added to the top stages of the combustor, and volatile solid fuels are added at an intermediate stage.

  17. Complement (C5)-derived chemotactic activity accounts for accumulation of polymorphonuclear leukocytes in cerebrospinal fluid of rabbits with pneumococcal meningitis.

    PubMed Central

    Ernst, J D; Hartiala, K T; Goldstein, I M; Sande, M A

    1984-01-01

    Experiments were performed to identify the chemoattractant for polymorphonuclear leukocytes that appears in the cerebrospinal fluid of rabbits with experimental pneumococcal meningitis. Meningitis was induced in anesthetized New Zealand white rabbits by injecting 10(4) cells of stationary-phase Streptococcus pneumoniae type III intracisternally. Before bacteria were injected, cerebrospinal fluid contained neither polymorphonuclear leukocytes nor chemotactic activity. Significant chemotactic activity for rabbit polymorphonuclear leukocytes was detected 12 h after inoculation with bacteria and was maximal after 18 to 20 h. Chemotactic activity appeared in cerebrospinal fluid while concentrations of pneumococci and total protein were increasing but before there was any accumulation of polymorphonuclear leukocytes. The chemotactic activity in cerebrospinal fluid was heat stable (56 degrees C for 30 min), eluted from Sephadex G-75 with a profile identical to that of the chemotactic activity in zymosan-activated rabbit serum, and was inhibited by treatment with antibodies to native human C5. In addition, preincubation of polymorphonuclear leukocytes with partially purified rabbit C5a selectively inhibited their subsequent chemotactic responses to cerebrospinal fluid. These data indicate that complement (C5)-derived chemotactic activity appears in cerebrospinal fluid during the course of experimental pneumococcal meningitis in rabbits and suggest that this activity accounts for the accumulation of polymorphonuclear leukocytes observed in this infection. PMID:6480117

  18. Combination of granular activated carbon adsorption and deep-bed filtration as a single advanced wastewater treatment step for organic micropollutant and phosphorus removal.

    PubMed

    Altmann, Johannes; Rehfeld, Daniel; Träder, Kai; Sperlich, Alexander; Jekel, Martin

    2016-04-01

    Adsorption onto granular activated carbon (GAC) is an established technology in water and advanced wastewater treatment for the removal of organic substances from the liquid phase. Besides adsorption, the removal of particulate matter by filtration and biodegradation of organic substances in GAC contactors has frequently been reported. The application of GAC as both adsorbent for organic micropollutant (OMP) removal and filter medium for solids retention in tertiary wastewater filtration represents an energy- and space saving option, but has rarely been considered because high dissolved organic carbon (DOC) and suspended solids concentrations in the influent of the GAC adsorber put a significant burden on this integrated treatment step and might result in frequent backwashing and unsatisfactory filtration efficiency. This pilot-scale study investigates the combination of GAC adsorption and deep-bed filtration with coagulation as a single advanced treatment step for simultaneous removal of OMPs and phosphorus from secondary effluent. GAC was assessed as upper filter layer in dual-media downflow filtration and as mono-media upflow filter with regard to filtration performance and OMP removal. Both filtration concepts effectively removed suspended solids and phosphorus, achieving effluent concentrations of 0.1 mg/L TP and 1 mg/L TSS, respectively. Analysis of grain size distribution and head loss within the filter bed showed that considerable head loss occurred in the topmost filter layer in downflow filtration, indicating that most particles do not penetrate deeply into the filter bed. Upflow filtration exhibited substantially lower head loss and effective utilization of the whole filter bed. Well-adsorbing OMPs (e.g. benzotriazole, carbamazepine) were removed by >80% up to throughputs of 8000-10,000 bed volumes (BV), whereas weakly to medium adsorbing OMPs (e.g. primidone, sulfamethoxazole) showed removals <80% at <5,000 BV. In addition, breakthrough behavior was

  19. Spontaneous activity of cochlear hair cells triggered by fluid secretion mechanism in adjacent support cells

    PubMed Central

    Wang, Han Chin; Lin, Chun-Chieh; Cheung, Rocky; Zhang-Hooks, YingXin; Agarwal, Amit; Ellis-Davies, Graham; Rock, Jason; Bergles, Dwight E.

    2015-01-01

    Summary Spontaneous electrical activity of neurons in developing sensory systems promotes their maturation and proper connectivity. In the auditory system, spontaneous activity of cochlear inner hair cells (IHCs) is initiated by the release of ATP from glia-like inner supporting cells (ISCs), facilitating maturation of central pathways before hearing onset. Here, we find that ATP stimulates purinergic autoreceptors in ISCs, triggering Cl− efflux and osmotic cell shrinkage by opening TMEM16A Ca2+-activated Cl− channels. Release of Cl− from ISCs also forces K+ efflux, causing transient depolarization of IHCs near ATP release sites. Genetic deletion of TMEM16A markedly reduces the spontaneous activity of IHCs and spiral ganglion neurons in the developing cochlea, and prevents ATP-dependent shrinkage of supporting cells. These results indicate that support cells in the developing cochlea have adapted a pathway used for fluid secretion in other organs to induce periodic excitation of hair cells. PMID:26627734

  20. NIR spectroscopic method for the in-line moisture assessment during drying in a six-segmented fluid bed dryer of a continuous tablet production line: Validation of quantifying abilities and uncertainty assessment.

    PubMed

    Fonteyne, Margot; Arruabarrena, Julen; de Beer, Jacques; Hellings, Mario; Van Den Kerkhof, Tom; Burggraeve, Anneleen; Vervaet, Chris; Remon, Jean Paul; De Beer, Thomas

    2014-11-01

    This study focuses on the thorough validation of an in-line NIR based moisture quantification method in the six-segmented fluid bed dryer of a continuous from-powder-to-tablet manufacturing line (ConsiGma™ 25, GEA Pharma Systems nv, Wommelgem, Belgium). The moisture assessment ability of an FT-NIR spectrometer (Matrix™-F Duplex, Bruker Optics Ltd, UK) equipped with a fiber-optic Lighthouse Probe™ (LHP, GEA Pharma Systems nv, Wommelgem, Belgium) was investigated. Although NIR spectroscopy is a widely used technique for in-process moisture determination, a minority of NIR spectroscopy methods is thoroughly validated. A moisture quantification PLS model was developed. Twenty calibration experiments were conducted, during which spectra were collected at-line and then regressed versus the corresponding residual moisture values obtained via Karl Fischer measurements. The developed NIR moisture quantification model was then validated by calculating the accuracy profiles on the basis of the analysis results of independent in-line validation experiments. Furthermore, as the aim of the NIR method is to replace the destructive, time-consuming Karl Fischer titration, it was statistically demonstrated that the new NIR method performs at least as good as the Karl Fischer reference method.

  1. Anaerobic degradation of 2,4,6-trinitrotoluene in granular activated carbon fluidized bed and batch reactors.

    PubMed

    Moteleb, M A; Suidan, M T; Kim, J; Davel, J L; Adrian, N R

    2001-01-01

    In this study, an anaerobic fluidized bed reactor (AFBR) was used to treat a synthetically produced pink water waste stream containing trinitrotoluene (TNT). The synthesized waste consisted of 95 mg/l-TNT, the main contaminant in pink water, which was to be co-metabolized with 560-mg/l ethanol. Granular activated carbon was used as the attachment medium for biological growth. TNT was reduced to a variety of compounds, mainly 2,4,6-triaminotoluene (2,4,6-TAT), 2,4-diamino-6-nitrotoluene (2,4-DA-6-NT), 2,6-diamino-4-nitrotoluene (2,6-DA-4-NT), 2-amino-4,6-dinitrotoluene (2-A-4,6-DNT), and 4-amino-2,6-dinitrotoluene (4-A-2,6-DNT). These conversions resulted through the oxidation of ethanol to carbon dioxide under anoxic conditions, or reduction to methane under methanogenic conditions. The anaerobic reactor was charged with 1.0 kg of 16 x 20 U.S. Mesh Granular Activated Carbon (GAC) and was pre-loaded with 200 g of TNT prior to the addition of the mixed seed culture. During the first three weeks of operation, ethanol was completely degraded and no methane was produced. Effluent inorganic carbon revealed stoichiometric conversion of the feed ethanol to dissolved inorganic carbon with accumulation of carbon dioxide in the headspace of the reactor. GAC extraction showed incremental reduction of the nitro groups to amino groups, with 2,4,6-TAT as the final product. After three weeks, the oxygen from the nitro groups was depleted and methane production commenced. The reproducibility of this phenomenon was confirmed by repeating the experiment in the same manner using an identical AFBR. Furthermore, serum bottle tests were conducted using TNT loading ratios of 0.2, 0.4, 0.8, 1.0 g-TNT/g-GAC as well as experiments in the absence of GAC. Similar behavior to that of the columns was observed, with degradation rates varying according to the particular condition. GAC greatly enhanced the degradation rates and the higher TNT loading resulted in slower degradation rates of ethanol.

  2. Antimicrobial activity and composition profile of grape (Vitis vinifera) pomace extracts obtained by supercritical fluids.

    PubMed

    Oliveira, Daniela A; Salvador, Ana Augusta; Smânia, Artur; Smânia, Elza F A; Maraschin, Marcelo; Ferreira, Sandra R S

    2013-04-10

    The possibility of increasing the aggregated value of the huge amount of residues generated by wineries around the world foment studies using the grape pomace - the residue from the wine production, composed by seed, skin and stems - to obtain functional ingredients. Nowadays, consumers in general prefer natural and safe products mainly for food and cosmetic fields, where the supercritical fluid extraction is of great importance due to the purity of the extracts provided. Therefore, the objective of this work is to evaluate the global extraction yield, the antimicrobial activity and the composition profile of Merlot and Syrah grape pomace extracts obtained by supercritical CO2 (SC-CO2) and CO2 added with co-solvent at pressures up to 300 bar and temperatures of 50 and 60 °C. The results were compared with the ones obtained by Soxhlet and by ultrasound-assisted leaching extraction methods. The main components from the extracts, identified by HPLC, were gallic acid, p-OH-benzoic acid, vanillic acid and epicatechin. The antibacterial and antifungal activities of the extracts were evaluated using four strains of bacteria (Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa) and three fungi strains (Candida albicans, Candida parapsilosis, Candida krusei). Despite lower extraction yield results, the supercritical fluid extracts presented the highest antimicrobial effectiveness compared to the other grape pomace extracts due to the presence of antimicrobial active compounds. Syrah extracts were less efficient against the microorganisms tested and Merlot extracts were more active against Gram-positive bacteria.

  3. Effects of Intense Physical Activity with Free Water Replacement on Bioimpedance Parameters and Body Fluid Estimates

    NASA Astrophysics Data System (ADS)

    Neves, E. B.; Ulbricht, L.; Krueger, E.; Romaneli, E. F. R.; Souza, M. N.

    2012-12-01

    Authors have emphasized the need for previous care in order to perform reliable bioimpedance acquisition. Despite of this need some authors have reported that intense physical training has little effect on Bioimpedance Analysis (BIA), while other ones have observed significant effects on bioimpedance parameters in the same condition, leading to body composition estimates considered incompatible with human physiology. The aim of this work was to quantify the changes in bioimpedance parameters, as well as in body fluids estimates by BIA, after four hours of intense physical activity with free water replacement in young males. Xitron Hydra 4200 equipment was used to acquire bioimpedance data before and immediately after the physical training. After data acquisition body fluids were estimates from bioimpedance parameters. Height and weight of all subjects were also acquired to the nearest 0.1 cm and 0.1 kg, respectively. Results point that among the bioimpedance parameter, extracellular resistance presented the most coherent behavior, leading to reliable estimates of the extracellular fluid and part of the total body water. Results also show decreases in height and weight of the participants, which were associated to the decrease in body hydration and in intervertebral discs.

  4. Fluid shear stress stimulates MATE2-K expression via Nrf2 pathway activation.

    PubMed

    Fukuda, Yasunori; Kaishima, Misato; Ohnishi, Toshiyuki; Tohyama, Kimio; Chisaki, Ikumi; Nakayama, Yusuke; Ogasawara-Shimizu, Mari; Kawamata, Yuji

    2017-03-04

    Accurate prediction of drug-induced renal toxicity is necessary for development of safer drugs for patients. Cellular assay systems that recapitulate physiologically relevant microenvironments have been proposed for correct estimation of drug responses in the human body. However, establishment of such assay systems for accurate prediction of renal toxicity is challenging because of the lack of readily available in vitro assay systems. In this study, we investigated the cellular response to fluid shear stress, which is a characteristic of the environment in the kidney proximal tubules, using microfluidic devices. The global gene expression profiles of human primary proximal tubule cells under the fluidic conditions revealed upregulation of MATE2-K and activation of Nrf2 signaling in response to fluid shear stress. Network and cell biological analysis additionally showed that expression of MATE2-K is regulated by Nrf2 signaling. These results strongly suggest that fluid shear stress is involved in the expression and maintenance of function of tissue-specific drug transporters in the proximal tubule, where the cells are exposed to continuous shear stress by primary urine. Furthermore, the microfluidic culture of human proximal tubules was demonstrated to be a useful system to analyze the regulatory mechanisms of gene expression in physiologically relevant cell conditions.

  5. A 2D suspension of active agents: the role of fluid mediated interactions.

    PubMed

    Behmadi, Hojjat; Fazli, Zahra; Najafi, Ali

    2017-03-22

    Taking into account both the Vicsek short-range ordering and the far-field hydrodynamic interactions mediated by the ambient fluid, we investigate the role of long-range interactions in the ordering phenomena in a quasi 2-dimensional active suspension. By studying the number fluctuations, the velocity correlation functions and cluster size distribution function, we show that depending on the number density of swimmers and the strength of noise, the hydrodynamic interactions can have significant effects in a suspension. For a fixed value of noise, at larger density of particles, long-range interactions enhance the particle pairing and cluster formation in the system.

  6. A 2D suspension of active agents: the role of fluid mediated interactions

    NASA Astrophysics Data System (ADS)

    Behmadi, Hojjat; Fazli, Zahra; Najafi, Ali

    2017-03-01

    Taking into account both the Vicsek short-range ordering and the far-field hydrodynamic interactions mediated by the ambient fluid, we investigate the role of long-range interactions in the ordering phenomena in a quasi 2-dimensional active suspension. By studying the number fluctuations, the velocity correlation functions and cluster size distribution function, we show that depending on the number density of swimmers and the strength of noise, the hydrodynamic interactions can have significant effects in a suspension. For a fixed value of noise, at larger density of particles, long-range interactions enhance the particle pairing and cluster formation in the system.

  7. Heat and Mass Transfer in Unsteady Rotating Fluid Flow with Binary Chemical Reaction and Activation Energy

    PubMed Central

    Awad, Faiz G.; Motsa, Sandile; Khumalo, Melusi

    2014-01-01

    In this study, the Spectral Relaxation Method (SRM) is used to solve the coupled highly nonlinear system of partial differential equations due to an unsteady flow over a stretching surface in an incompressible rotating viscous fluid in presence of binary chemical reaction and Arrhenius activation energy. The velocity, temperature and concentration distributions as well as the skin-friction, heat and mass transfer coefficients have been obtained and discussed for various physical parametric values. The numerical results obtained by (SRM) are then presented graphically and discussed to highlight the physical implications of the simulations. PMID:25250830

  8. Evidence of cellular immune activation in children with opsoclonus-myoclonus: cerebrospinal fluid neopterin.

    PubMed

    Pranzatelli, Michael R; Hyland, Keith; Tate, Elizabeth D; Arnold, Lauren A; Allison, Tyler J; Soori, Gamini S

    2004-12-01

    To evaluate cellular immune activation in opsoclonus-myoclonus syndrome, we measured the inflammatory marker neopterin in the cerebrospinal fluid of 16 children with opsoclonus-myoclonus and neuroblastoma, 24 children with opsoclonus-myoclonus but no tumor, and 19 age-matched controls. The mean concentration in opsoclonus-myoclonus was 2.3-fold higher than in controls (P = .008). Neopterin was greatly elevated in four of the most neurologically severe cases, up to 8.3-fold above the highest control level. Thirteen of the 40 children with opsoclonus-myoclonus but no controls had a neopterin concentration >2 SD above the control mean (P = .005). In this high neopterin subgroup, neurologic severity was significantly greater and the duration of neurologic symptoms was less. In 16 children re-examined on immunotherapy, including adrenocorticotropic hormone (ACTH) combination therapy, treatment was associated with a significant reduction in both neopterin and neurologic severity. Neopterin did not differ significantly between the tumor and non-tumor opsoclonus-myoclonus etiologies. No abnormalities of tetrahydrobiopterin were found. Although cerebrospinal fluid neopterin lacked the sensitivity to be a biomarker of disease activity in opsoclonus-myoclonus, elevated concentrations do support a role for T-cell activation and cell-mediated immunity in its pathophysiology.

  9. Computational Fluid Dynamics Simulation Study of Active Power Control in Wind Plants

    SciTech Connect

    Fleming, Paul; Aho, Jake; Gebraad, Pieter; Pao, Lucy; Zhang, Yingchen

    2016-08-01

    This paper presents an analysis performed on a wind plant's ability to provide active power control services using a high-fidelity computational fluid dynamics-based wind plant simulator. This approach allows examination of the impact on wind turbine wake interactions within a wind plant on performance of the wind plant controller. The paper investigates several control methods for improving performance in waked conditions. One method uses wind plant wake controls, an active field of research in which wind turbine control systems are coordinated to account for their wakes, to improve the overall performance. Results demonstrate the challenge of providing active power control in waked conditions but also the potential methods for improving this performance.

  10. [Aminopeptidases activity in the amniotic fluid in women in labor with EPH-gestosis].

    PubMed

    Karmowski, A; Sobiech, K A; Malinowski, J; Nowacka, I; Pałczyński, B; Kertyńska, I

    2000-01-01

    The thesis of this work was to compare the aminopeptidases activity in the amniotic fluid obtained during the physiological labor and during the labor of pregnant with EPH-gestosis, in presence of the beta-naphtlamidic L-amino-acids (alanine, leucine, phenylalanine, tyrosine, histidine, cysteine) chromogenic substrates. It was assumed the 3-7 times increase in the aminopeptidases activity counted to the proteins from the labored with EPH-gestosis comparing to the labored in physiological labor. Among the used substrates the highest activity in both groups of labored women was measured in presence of substrates with exact amino-acids in this order: L-Ala > L-Leu > L-Phe > L-Tyr > L-His > L-Cys.

  11. Induced venous pooling and cardiorespiratory responses to exercise after bed rest

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.; Sandler, H.; Webb, P.; Annis, J. F.

    1982-01-01

    Venous pooling induced by a specially constructed garment is investigated as a possible means for reversing the reduction in maximal oxygen uptake regularly observed following bed rest. Experiments involved a 15-day period of bed rest during which four healthy male subjects, while remaining recumbent in bed, received daily 210-min venous pooling treatments from a reverse gradient garment supplying counterpressure to the torso. Results of exercise testing indicate that while maximal oxygen uptake endurance time and plasma volume were reduced and maximal heart rate increased after bed rest in the control group, those parameters remained essentially unchanged for the group undergoing venous pooling treatment. Results demonstrate the importance of fluid shifts and venous pooling within the cardiovascular system in addition to physical activity to the maintenance of cardiovascular conditioning.

  12. Inside Out: Active learning in fluid dynamics in and out of the classroom

    NASA Astrophysics Data System (ADS)

    Kaye, Nigel; Benson, Lisa; Sill, Ben

    2014-11-01

    Active learning can be broadly defined as any activity that engages students beyond just listening. But is it worth the effort, when we can just lecture and tell students all they need to know? Learning theories posit that students remember far more of what they say and do than of what they hear and see. The benefits of active learning include increased attendance (because class is now something different and attending is more worthwhile) and deeper understanding of concepts (because students get to practice answering and generating questions). A recent meta-analysis of research on active learning has summarized evidence of real outcomes of active learning. Research is showing that students' performance on exams are higher and that they fail at lower rates in classes that involve active learning compared to traditional lecturing. Other studies have shown evidence of improved performance in follow-on classes, showing that the improved learning lasts. There are some topics and concepts that are best taught (or at least introduced) through lecturing, but even lecturing can be broken up by short activities that engage students so they learn more effectively. In this presentation, we will review the findings of the meta study and provide examples of active learning both inside and outside the classroom that demonstrate simple ways of introducing this approach in fluid dynamics classes.

  13. Cytoskeletal protein Flightless (Flii) is elevated in chronic and acute human wounds and wound fluid: neutralizing its activity in chronic but not acute wound fluid improves cellular proliferation.

    PubMed

    Ruzehaji, Nadira; Grose, Randall; Krumbiegel, Doreen; Zola, Heddy; Dasari, Pallave; Wallace, Hilary; Stacey, Michael; Fitridge, Robert; Cowin, Allison J

    2012-01-01

    Chronic non-healing wounds form a medical need which will expand as the population ages and the obesity epidemic grows. Whilst the complex mechanisms underlying wound repair are not fully understood, remodelling of the actin cytoskeleton plays a critical role. Elevated expression of the actin cytoskeletal protein Flightless I (Flii) is known to impair wound outcomes. To determine if Flii is involved in the impaired healing observed in chronic wounds, its expression in non-healing human wounds from patients with venous leg ulcers was determined and compared to its expression in acute wounds and unwounded skin. Increased expression of Flii was observed in both chronic and acute wounds with wound fluid and plasma also containing secreted Flii protein. Inflammation is a key aspect of wound repair and fluorescence-activated cell sorting (FACS) analysis revealed Flii was located in neutrophils within the blood and that it co-localised with CD16+ neutrophils in chronic wounds. The function of secreted Flii was investigated as both chronic wound fluid and Flii have previously been shown to inhibit fibroblast proliferation. To determine if the inhibitory effect of wound fluid was due in part to the presence of Flii, wound fluids were depleted of Flii using Flii-specific neutralizing antibodies (FnAb). Flii depleted chronic wound fluid no longer inhibited fibroblast proliferation, suggesting that Flii may contribute to the inhibitory effect of chronic wound fluid on fibroblast function. Application of FnAbs to chronic wounds may therefore be a novel approach used to improve the local environment of non-healing wounds and potentially improve healing outcomes.

  14. Quantitation of fibroblast activation protein (FAP)-specific protease activity in mouse, baboon and human fluids and organs.

    PubMed

    Keane, Fiona M; Yao, Tsun-Wen; Seelk, Stefanie; Gall, Margaret G; Chowdhury, Sumaiya; Poplawski, Sarah E; Lai, Jack H; Li, Youhua; Wu, Wengen; Farrell, Penny; Vieira de Ribeiro, Ana Julia; Osborne, Brenna; Yu, Denise M T; Seth, Devanshi; Rahman, Khairunnessa; Haber, Paul; Topaloglu, A Kemal; Wang, Chuanmin; Thomson, Sally; Hennessy, Annemarie; Prins, John; Twigg, Stephen M; McLennan, Susan V; McCaughan, Geoffrey W; Bachovchin, William W; Gorrell, Mark D

    2013-01-01

    The protease fibroblast activation protein (FAP) is a specific marker of activated mesenchymal cells in tumour stroma and fibrotic liver. A specific, reliable FAP enzyme assay has been lacking. FAP's unique and restricted cleavage of the post proline bond was exploited to generate a new specific substrate to quantify FAP enzyme activity. This sensitive assay detected no FAP activity in any tissue or fluid of FAP gene knockout mice, thus confirming assay specificity. Circulating FAP activity was ∼20- and 1.3-fold less in baboon than in mouse and human plasma, respectively. Serum and plasma contained comparable FAP activity. In mice, the highest levels of FAP activity were in uterus, pancreas, submaxillary gland and skin, whereas the lowest levels were in brain, prostate, leukocytes and testis. Baboon organs high in FAP activity included skin, epididymis, bladder, colon, adipose tissue, nerve and tongue. FAP activity was greatly elevated in tumours and associated lymph nodes and in fungal-infected skin of unhealthy baboons. FAP activity was 14- to 18-fold greater in cirrhotic than in non-diseased human liver, and circulating FAP activity was almost doubled in alcoholic cirrhosis. Parallel DPP4 measurements concorded with the literature, except for the novel finding of high DPP4 activity in bile. The new FAP enzyme assay is the first to be thoroughly characterised and shows that FAP activity is measurable in most organs and at high levels in some. This new assay is a robust tool for specific quantitation of FAP enzyme activity in both preclinical and clinical samples, particularly liver fibrosis.

  15. Slow Granular Dynamics in River Beds: Toward a Continuous Definition of Bed Load Transport.

    NASA Astrophysics Data System (ADS)

    Houssais, M.; Ortiz, C. P.; Durian, D. J.; Jerolmack, D. J.

    2014-12-01

    Field records and experimental studies show that the fluvial geophysical processes that shape the landscape, such as debris flows and river sediment transport, are extremely unpredictable in large part due to the nonlinear dependence of the transport rates on the structural properties of the sediment. There is a need for a more fundamental understanding of the physical processes that control sediment transfer rates, particularly the magnitude and frequency of the bed load transport flux. We present experiments in a simple geometry, an annular couette cell, that allows us to study the free-surface dynamics at the interface between a flowing viscous fluid and a submerged particle bed made of plastic spheres, a highly idealized river. This geometry presents an opportunity to study details of the bed structure and particle transport with a well-controlled steady shear stress during long-time experiments. We use the refractive-index-matched laser scanning technique [Dijksman et al. 2012], to detect the particle positions on a two-dimensional vertical slice at the middle of the 15 particle wide bed, and characterize their dynamics over a range of timescales of six-orders of magnitude. We find that the particle dynamics are spatiotemporally heterogeneous, but that the overall flow field reaches a well-developed steady-state. Below the fluid flow depth, we find a wide flowing layer characterized by a fast, approximately exponential decay of the particle velocity versus depth. This layer can be associated with the active layer commonly mentioned in the literature. We find that the thickness of the flow layer increases with the applied shear stress. However, deep in the bed, the velocity profile does not indefinitely follow a exponential decay. Instead, the rate of decay of the velocity profile slows drastically, transitioning continuously to a quasistatic flow regime, with a very different exponential decay. This study provides a new framework for understanding the

  16. Novacon process: An alternative to limestone sorbents. Presentation to the Council of Industrial Boiler Owners, fluid bed XI. Held in Burke, Virginia, on November 14, 1995

    SciTech Connect

    Baer, S.H.; Luftglass, B.K.

    1995-12-31

    This paper presents the results of recent tests of a new type of sorbent useful for emissions control. The sorbent, referred to as thermally active marble (TAM), comprises a class of naturally-occurring metamorphic calcium carbonates. TAMs break down upon heating in combustors more evenly and with higher reactivity than limestone, resulting in better calcium utilization rates. Use of TAMS may also reduce NOx and CO emissions, excess air consumption and unburned carbon, and also improve combustion efficiency. In a full-scale (90 MW) demonstration comparing TAM to limestone, the Ca/S improved from 2.6 to 1.5 or better. Unburned carbon in fly ash decreased significantly and NOx levels were also reduced.

  17. From Concept-to-Flight: An Active Active Fluid Loop Based Thermal Control System for Mars Science Laboratory Rover

    NASA Technical Reports Server (NTRS)

    Birur, Gajanana C.; Bhandari, Pradeep; Bame, David; Karlmann, Paul; Mastropietro, A. J.; Liu, Yuanming; Miller, Jennifer; Pauken, Michael; Lyra, Jacqueline

    2012-01-01

    The Mars Science Laboratory (MSL) rover, Curiosity, which was launched on November 26, 2011, incorporates a novel active thermal control system to keep the sensitive electronics and science instruments at safe operating and survival temperatures. While the diurnal temperature variations on the Mars surface range from -120 C to +30 C, the sensitive equipment are kept within -40 C to +50 C. The active thermal control system is based on a single-phase mechanically pumped fluid loop (MPFL) system which removes or recovers excess waste heat and manages it to maintain the sensitive equipment inside the rover at safe temperatures. This paper will describe the entire process of developing this active thermal control system for the MSL rover from concept to flight implementation. The development of the rover thermal control system during its architecture, design, fabrication, integration, testing, and launch is described.

  18. Inhibition of fatty acid oxidation activates transforming growth factor-beta in cerebrospinal fluid and decreases spontaneous motor activity.

    PubMed

    Fujikawa, Teppei; Fujita, Ryo; Iwaki, Yoko; Matsumura, Shigenobu; Fushiki, Tohru; Inoue, Kazuo

    2010-10-05

    We have previously reported that transforming growth factor (TGF)-beta in the cerebrospinal fluid (CSF) is involved in the mechanism underlying the regulation of spontaneous motor activity (SMA) by the central nervous system after exercise. However, it remained unclear what physiological condition triggers the activation of TGF-beta. We hypothesized that the shortage of energy derived from fatty acid (FA) oxidation observed in the early phase of exercise activated TGF-beta in the CSF. To test this hypothesis, we investigated whether mercaptoacetate (MA), an inhibitor of FA oxidation, could induce an activation of TGF-beta in the CSF and a decrease in SMA. Intraperitoneal (i.p.) administration of MA activated TGF-beta in CSF in rats and depressed SMA; 2-deoxyglucose, an inhibitor of carbohydrate oxidation, on the other hand, depressed SMA but failed to activate CSF TGF-beta. Intracisternal administration of anti-TGF-beta antibody abolished the depressive effect of MA on SMA. We also found that the depression of SMA and the activation of TGF-beta in the CSF by i.p. MA administration were eliminated by vagotomy. Our data suggest that TGF-beta in the CSF is activated by the inhibition of FA oxidation via the vagus nerve and that this subsequently induces depression of SMA.

  19. First hydroacoustic evidence of marine, active fluid vents in the Naples Bay continental shelf (Southern Italy)

    NASA Astrophysics Data System (ADS)

    Passaro, Salvatore; Genovese, Simona; Sacchi, Marco; Barra, Marco; Rumolo, Paola; Tamburrino, Stella; Mazzola, Salvatore; Basilone, Gualtiero; Placenti, Francesco; Aronica, Salvatore; Bonanno, Angelo

    2014-09-01

    We present the first results of a multidisciplinary research aimed at the detection and mapping of Active Fluid Vents (AFVs) at the seafloor of the Naples Bay, Italy. This segment of the Campania continental margin is characterised by severe Quaternary extension and intense volcanism at Ischia and Procida islands, the Campi Flegrei and Somma-Vesuvius volcanic complexes. High resolution hydroacoustic profilers were used to identify and localize fluid emission from the seafloor. ROV direct observation showed that each emission centre is generally composed by the coalescence of several emitting points. CTD probes showed that there are no significant gradients in temperature profiles. The results of this study include the detection and mapping of 54 fluid emission points all located in the - 71/- 158 m depth range, and spatially distributed into four main clusters. Three of the described clusters are located along the margin of a complex, toe-shaped seafloor morphology southwest of the Somma-Vesuvius, representing the shallow expression of partly buried, coalesced depositional features (namely, two flank collapses and one pyroclastic flow) associated with the Late Pleistocene activity of the volcano. The fourth AFV cluster was detected at the morphological - high, located about 8 km south of Naples (Banco della Montagna), represented by a field of volcaniclastic diapirs composed of massive pumiceous deposits originated from the Campi Flegrei intruding rising through the latest Quaternary-Holocene marine deposits. Our study suggests that the occurrence of AFV in this area could be genetically linked to the interaction between volcanic related seafloor morphologies and the main, NE striking faults present in the area, i.e. the Magnaghi-Sebeto line and the Vesuvian fault.

  20. Influence of electromagnetic fields on the enzyme activity of rheumatoid synovial fluid cells in vitro.

    PubMed

    Mohamed-Ali, H; Kolkenbrock, H; Ulbrich, N; Sörensen, H; Kramer, K D; Merker, H J

    1994-04-01

    Since positive clinical effects have been observed in the treatment of rheumatoid arthritis with electromagnetic fields of weak strength and low frequency range (magnetic field strength: 70 microT; frequency: 1.36-14.44 Hz), an attempt was made to analyse the effects of these electromagnetic fields on enzyme activity in monolayer cultures of rheumatoid synovial fluid cells after single irradiation of the cultures for 24 hours. We only investigated the matrix metalloproteinases (collagenase, gelatinase, proteinase 24.11 and aminopeptidases). It was found that electromagnetic fields of such a weak strength and low frequency range do not generally have a uniform effect on the activity of the different proteinases in vitro. While aminopeptidases do not show any great changes in activity, the peptidases hydrolysing N(2,4)-dinitrophenyl-peptide exhibit a distinct increase in activity in the late phase in culture medium without fetal calf serum. In the presence of fetal calf serum this effect is not observed and enzyme activity is diminished. Our experiments do not show whether such a phase-bound increase in the activity of proteinases in vitro is only one finding in a much broader range of effects of electromagnetic fields, or whether it is a specific effect of weak pulsed magnetic fields of 285 +/- 33 nT on enzyme activity after single irradiation. This question requires further elucidation.

  1. Adsorption and desorption of noble gases on activated charcoal: II. sup 222 Rn studies in a monolayer and packed bed

    SciTech Connect

    Scarpitta, S.C.; Harley, N.H. )

    1990-10-01

    The adsorptive and desorptive characteristics of canisters containing a petroleum-based charcoal were investigated under controlled conditions of temperature, relative humidity, and Rn concentration. Charcoals exposed in a monolayer and packed bed during exposure intervals of 1-7 d demonstrate that Rn adsorption and desorption are dependent on bed depth and the amount of water adsorbed. Changes in the adsorptive and desorptive properties of the charcoal occurred near the break-point where the pores became occluded by water vapor that condenses in the entrance capillaries. Radon-222 adsorption is decreased by an order of magnitude as the amount of adsorbed water exceeds the break-point of the charcoal. The reduction in pore surface due to adsorbed water results in a marked increase in the rate of Rn loss from exposed canisters, accounting for reduced adsorption. The apparent desorption time-constant for a 2-cm bed of loose Witco 6 x 10 mesh charcoal containing 0.220-0.365 kg H{sub 2}O kg-1 is typically between 2-8 h. The apparent desorption time-constant for an equivalent packed bed containing a water vapor content of 0.026-0.060 kg H{sub 2}O kg-1, which is below the break-point of the charcoal, is about 15-30 h. Conventional charcoal canisters, if exposed in the fully-opened configuration, can achieve the break-point in less than 4 d at 70% humidity. The use of a diffusion barrier would allow for longer exposure times until the break-point of the charcoal is achieved.

  2. Orbital fluid shear stress promotes osteoblast metabolism, proliferation and alkaline phosphates activity in vitro.

    PubMed

    Aisha, M D; Nor-Ashikin, M N K; Sharaniza, A B R; Nawawi, H; Froemming, G R A

    2015-09-10

    Prolonged disuse of the musculoskeletal system is associated with reduced mechanical loading and lack of anabolic stimulus. As a form of mechanical signal, the multidirectional orbital fluid shear stress transmits anabolic signal to bone forming cells in promoting cell differentiation, metabolism and proliferation. Signals are channeled through the cytoskeleton framework, directly modifying gene and protein expression. For that reason, we aimed to study the organization of Normal Human Osteoblast (NHOst) cytoskeleton with regards to orbital fluid shear (OFS) stress. Of special interest were the consequences of cytoskeletal reorganization on NHOst metabolism, proliferation, and osteogenic functional markers. Cells stimulated at 250 RPM in a shaking incubator resulted in the rearrangement of actin and tubulin fibers after 72 h. Orbital shear stress increased NHOst mitochondrial metabolism and proliferation, simultaneously preventing apoptosis. The ratio of RANKL/OPG was reduced, suggesting that orbital shear stress has the potential to inhibit osteoclastogenesis and osteoclast activity. Increase in ALP activity and OCN protein production suggests that stimulation retained osteoblast function. Shear stress possibly generated through actin seemed to hold an anabolic response as osteoblast metabolism and functional markers were enhanced. We hypothesize that by applying orbital shear stress with suitable magnitude and duration as a non-drug anabolic treatment can help improve bone regeneration in prolonged disuse cases.

  3. Gravity monitoring of Tatun Volcanic Group activities and inference for underground fluid circulations

    NASA Astrophysics Data System (ADS)

    Mouyen, Maxime; Chao, Benjamin Fong; Hwang, Cheinway; Hsieh, Wen-Chi

    2016-12-01

    The Tatun Volcano Group (TVG), located on the northern coast of Taiwan adjacent to the city of Taipei, experiences active hydrothermalism but has no historical record of volcanic eruption. Yet recent studies suggest that TVG is dormant-active rather than extinct. To monitor mass transfers and to gain further understanding of this volcanic area, gravity variations have been recorded continuously since 2012 using a superconducting gravimeter, and once every few months since 2005 using absolute gravimeters. We analyze the continuous gravity time series and propose a model that best explains the gravity variations due to local groundwater redistribution. By correcting these variations, we identify gravity changes as large as 35 μGal that occurred concomitantly to fluid pressure-induced earthquakes and changes in the gas composition at Dayoukeng, one of TVG's fumaroles, over 2005-2007. We examine several fluid movements that can match the gravity observations, yet too few additional constraints exist to favor any of them. In particular, no significant ground displacements are observed when these gravity variations occurred. On the other hand, the model of gravity changes due to local groundwater redistribution can be routinely computed and removed from the ongoing time gravity measurements in order to quickly identify any unusual mass transfer occurring beneath TVG.

  4. Predominant bacteria in an activated sludge reactor for the degradation of cutting fluids

    SciTech Connect

    Baker, C.A.; Claus, G.W.; Taylor, P.A.

    1983-01-01

    For the first time, an activated sludge reactor, established for the degradation of cutting fluids, was examined for predominant bacteria. In addition, both total and viable numbers of bacteria in the reactor were determined so that the percentage of each predominant type in the total reactor population could be determined. Three samples were studied, and a total of 15 genera were detected. In each sample, the genus Pseudomonas and the genus Microcyclus were present in high numbers. Three other genera, Acinetobacter, Alcaligenes, and Corynebacterium, were also found in every sample but in lower numbers. In one sample, numerous appendage bacteria were present, and one of these, the genus Seliberia, was the most predominant organism in that sample. However, in the other two samples no appendage bacteria were detected. Six genera were found in this reactor which have not been previously reported in either cutting fluids in use or in other activated sludge systems. These genera were Aeromonas, Hyphomonas, Listeria, Microcyclus, Moraxella, and Spirosoma. None of the predominant bacterial belonged to groups of strict pathogens. 22 references, 6 figures, 3 tables.

  5. Peering inside the granular bed: illuminating feedbacks between bed-load transport and bed-structure evolution

    NASA Astrophysics Data System (ADS)

    Houssais, M.; Jerolmack, D. J.; Martin, R. L.

    2013-12-01

    The threshold of motion is perhaps the most important quantity to determine for understanding rates of bed load transport, however it is a moving target. Decades of research show that it changes in space and in time within a river, and is highly variable among different systems; however, these differences are not mechanistically understood. Recent researchers have proposed that the critical Shields stress is strongly dependent on the local configuration of the sediment bed [Frey and Church, 2011]. Critical Shields stress has been observed to change following sediment-transporting flood events in natural rivers [e.g., Turowski et al., 2011], while small-scale laboratory experiments have produced declining bed load transport rates associated with slow bed compaction [Charru et al., 2004]. However, no direct measurements have been made of the evolving bed structure under bed load transport, so the connection between granular controls and the threshold of motion remains uncertain. A perspective we adopt is that granular effects determine the critical Shields stress, while the fluid supplies a distribution of driving stresses. In order to isolate the granular effect, we undertake laminar bed load transport experiments using plastic beads sheared by a viscous oil in a small, annular flume. The fluid and beads are refractive index matched, and the fluid impregnated with a fluorescing powder. When illuminated with a planar laser sheet, we are able to image slices of the granular bed while also tracking the overlying sediment transport. We present the first results showing how bed load transport influences granular packing, and how changes in packing influence the threshold of motion to feed back on bed load transport rates. This effect may account for much of the variability observed in the threshold of motion in natural streams, and by extension offers a plausible explanation for hysteresis in bed load transport rates observed during floods. Charru, F., H. Mouilleron, and

  6. Packed Bed Reactor Experiment

    NASA Video Gallery

    The purpose of the Packed Bed Reactor Experiment in low gravity is to determine how a mixture of gas and liquid flows through a packed bed in reduced gravity. A packed bed consists of a metal pipe ...

  7. Immune activation in amniotic fluid from Zika virus-associated microcephaly.

    PubMed

    Ornelas, Alice M M; Pezzuto, Paula; Silveira, Paola P; Melo, Fabiana O; Ferreira, Thales A; Oliveira-Szejnfeld, Patricia S; Leal, Jeime I; Amorim, Melania M R; Hamilton, Stuart; Rawlinson, William D; Cardoso, Cynthia C; Nixon, Douglas F; Tanuri, Amilcar; Melo, Adriana S; Aguiar, Renato S

    2017-01-01

    Recent advances in the understanding of neuropathogenesis associated with Zika virus (ZIKV) infection has led to descriptions of neonatal microcephaly cases. However, none of these reports have evaluated the humoral response during ZIKV infection. We report here polyfunctional immune activation associated with increased interferon-gamma-inducible protein 10, interleukin (IL)-6, IL-8, vascular endothelial growth factor (VEGF), monocyte chemoattractive protein 1 (MCP-1), and granulocyte colony-stimulating factor (G-CSF) levels in the amniotic fluid of ZIKV-positive pregnant women with neonatal microcephaly. These cytokines have been associated not only with neuronal damage, but also with differentiation and proliferation of neural progenitor cells. Our results suggested that the immune activation caused by ZIKV infection in the uterine environment could also interfere with fetal development. ANN NEUROL 2017;81:152-156.

  8. Embryo as an active granular fluid: stress-coordinated cellular constriction chains

    NASA Astrophysics Data System (ADS)

    Holcomb, Michael; Gao, Guo-Jie; Thomas, Jeffrey; Blawzdziewicz, Jerzy

    2016-11-01

    Mechanical stress plays an intricate role in gene expression in individual cells and sculpting of developing tissues. Motivated by our observation of the cellular constriction chains (CCCs) during the initial phase of ventral furrow formation in the Drosophila melanogaster embryo, we propose an active granular fluid (AGF) model that provides valuable insights into cellular coordination in the apical constriction process. In our model, cells are treated as circular particles connected by a predefined force network, and they undergo a random constriction process in which the particle constriction probability P is a function of the stress exerted on the particle by its neighbors. We find that when P favors tensile stress, constricted particles tend to form chain-like structures. In contrast, constricted particles tend to form compact clusters when P favors compression. A remarkable similarity of constricted-particle chains and CCCs observed in vivo provides indirect evidence that tensile-stress feedback coordinates the apical constriction activity.

  9. New topic of supercritical fluids: Local activity coefficients of supercritical solvent and cosolvent around solute

    NASA Astrophysics Data System (ADS)

    Hou, Minqiang; Zhang, Xiaogang; Han, Buxing; Song, Jiyuan; Liu, Gang; Zhang, Zhaofu; Zhang, Jianling

    2008-03-01

    The study of inhomogeneity in supercritical fluids (SCFs) is of great importance. In this work, we propose the concept of local activity coefficients in supercritical (SC) solutions, which link thermodynamics and inhomogeneity in SC systems. The local activity coefficients of CO2+acetonitrile+phenol blue and CO2+aceticacid+phenol blue systems are investigated at 308.15K in critical region and outside critical region. To do this, the local compositions of CO2+acetonitrile and CO2+acetic acid mixed solvents around phenol blue are first estimated using UV-visible spectroscopy. Then it is considered that there exist bulk phase and local phase around phenol blue in the systems. The activity coefficients of CO2 and the cosolvents (acetonitrile or acetic acid) in bulk phase are calculated using Peng-Robinson equation of state. The local activity coefficients of CO2 and the cosolvents are then calculated on the basis of thermodynamic principles. It is demonstrated that in the critical region the local activity coefficients differ from bulk activity coefficients significantly and are sensitive to pressure. This can explain many unusual phenomena in SC systems in critical region thermodynamically.

  10. New topic of supercritical fluids: local activity coefficients of supercritical solvent and cosolvent around solute.

    PubMed

    Hou, Minqiang; Zhang, Xiaogang; Han, Buxing; Song, Jiyuan; Liu, Gang; Zhang, Zhaofu; Zhang, Jianling

    2008-03-14

    The study of inhomogeneity in supercritical fluids (SCFs) is of great importance. In this work, we propose the concept of local activity coefficients in supercritical (SC) solutions, which link thermodynamics and inhomogeneity in SC systems. The local activity coefficients of CO(2)+acetonitrile+phenol blue and CO(2)+acetic acid+phenol blue systems are investigated at 308.15 K in critical region and outside critical region. To do this, the local compositions of CO(2)+acetonitrile and CO(2)+acetic acid mixed solvents around phenol blue are first estimated using UV-visible spectroscopy. Then it is considered that there exist bulk phase and local phase around phenol blue in the systems. The activity coefficients of CO(2) and the cosolvents (acetonitrile or acetic acid) in bulk phase are calculated using Peng-Robinson equation of state. The local activity coefficients of CO(2) and the cosolvents are then calculated on the basis of thermodynamic principles. It is demonstrated that in the critical region the local activity coefficients differ from bulk activity coefficients significantly and are sensitive to pressure. This can explain many unusual phenomena in SC systems in critical region thermodynamically.

  11. Model study of the effects of interactions between systemic and peripheral circulation on interstitial fluid balance.

    PubMed

    Aletti, Federico; Baselli, Giuseppe

    2007-07-01

    Interstitial fluid balance is severely altered in microgravity, but the mechanisms underlying the fluid shift from lower to upper body are still partially unclear. A lumped parameter model of the arterial tree with active and non linear modulation of peripheral resistances and capillary fluid exchange was adopted to simulate the response of microcirculation to pulsatility and edema. Results suggest that myogenic regulation not only impinges on arteriolar radius, but it also indirectly affects interstitial fluid balance. Non linear dynamics of blood pressure (BP) and flow in capillary beds are influenced by systemic pulsatility, hinting that local activity is involved in the response to peripheral edema as well.

  12. The feedback between active tectonics, fluid flow and mineralization in an Andean geotermal reservoir

    NASA Astrophysics Data System (ADS)

    Reich, M.; Arancibia, G.; Perez, P.; Sanchez, P.; Cembrano, J. M.; Stimac, J. A.; Lohmar, S.

    2012-12-01

    In the Andean Cordillera of Central-Southern Chile, geothermal resources occur in close spatial relationship with active volcanism. The nature of the relationship between tectonics and volcanism in this region is the result of interaction between the crustal structures of the basement and the ongoing regional stress field, which is primarily controlled by the oblique convergence of the Nazca and South America Plates. Between 39° and 46°S, the volcanic and geothermal activity is controlled by the NNE-trending, 1,000 km long Liquiñe-Ofqui Fault Zone (LOFZ), an intra-arc dextral strike-slip fault system. Although there is consensus that volcanism (and hence geothermal activity) in southern Chile is largely controlled by the regional-scale tectonic stress field and architecture of the volcanic arc, there is limited scientific information about the role of local kinematic conditions on fluid flow and mineralization during the development and evolution of geothermal reservoirs. In this report, we present the preliminary results of an undergoing structural, mineralogical and geochemical study of the Tolhuaca geothermal system in southern Chile. The Tolhuaca geothermal reservoir formed as a liquid-dominated hydrothermal system, where shallow upflow resulted in near-boiling temperatures in a roughly horizontal liquid reservoir at 100-200 m depth (Melosh et al., 2010, 2012). In an early stage of evolution, hydrothermal brecciation and phase-separation (boiling) episodes penetrated at least 950 m depth into the deeper reservoir, and boiling was followed by steam-heated water invasion that cooled the reservoir. In a later stage, the preliminary conceptual model involves boiling and reheating of the reservoir, forming a system with deep hot brines that is connected to the shallow steam zone by an upflow conduit that is characterized by high-temperature mineralogy. The structural analysis of veins, fault-veins and faults of the Tol-1 drillcore (~1080 m depth) provide insights

  13. Pressurized fluidized bed reactor

    DOEpatents

    Isaksson, J.

    1996-03-19

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine. 1 fig.

  14. Pressurized fluidized bed reactor

    DOEpatents

    Isaksson, Juhani

    1996-01-01

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine.

  15. Active Model H: Scalar Active Matter in a Momentum-Conserving Fluid

    NASA Astrophysics Data System (ADS)

    Tiribocchi, Adriano; Wittkowski, Raphael; Marenduzzo, Davide; Cates, Michael E.

    2015-10-01

    We present a continuum theory of self-propelled particles, without alignment interactions, in a momentum-conserving solvent. To address phase separation, we introduce a dimensionless scalar concentration field ϕ with advective-diffusive dynamics. Activity creates a contribution Σi j=-κ ^ [(∂iϕ )(∂jϕ )-(∇ϕ )2δi j/d ] to the deviatoric stress, where κ ^ is odd under time reversal and d is the number of spatial dimensions; this causes an effective interfacial tension contribution that is negative for contractile swimmers. We predict that domain growth then ceases at a length scale where diffusive coarsening is balanced by active stretching of interfaces, and confirm this numerically. Thus, there is a subtle interplay of activity and hydrodynamics, even without alignment interactions.

  16. RADIOACTIVE DEMONSTRATIONS OF FLUIDIZED BED STEAM REFORMING AS A SUPPLEMENTARY TREATMENT FOR HANFORD'S LOW ACTIVITY WASTE AND SECONDARY WASTES

    SciTech Connect

    Jantzen, C.; Crawford, C.; Cozzi, A.; Bannochie, C.; Burket, P.; Daniel, G.

    2011-02-24

    The U.S. Department of Energy's Office of River Protection (ORP) is responsible for the retrieval, treatment, immobilization, and disposal of Hanford's tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project (RPP) cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the RPP mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA), i.e. December 31, 2047. Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. The Supplemental Treatment chosen will immobilize that portion of the retrieved LAW that is not sent to the WTP's LAW Vitrification facility into a solidified waste form. The solidified waste will then be disposed on the Hanford site in the Integrated Disposal Facility (IDF). In addition, the WTP LAW vitrification facility off-gas condensate known as WTP Secondary Waste (WTP-SW) will be generated and enriched in volatile components such as Cs-137, I-129, Tc-99, Cl, F, and SO4 that volatilize at the vitrification temperature of 1150 C in the absence of a continuous cold cap. The current waste disposal path for the WTP-SW is to recycle it to the supplemental LAW treatment to avoid a large steady state accumulation in the pretreatment-vitrification loop. Fluidized Bed Steam Reforming (FBSR) offers a moderate temperature (700-750 C) continuous method by which LAW and/or WTP-SW wastes can be processed irrespective of whether they contain organics, nitrates, sulfates/sulfides, chlorides

  17. Hydrothermal fluids circulation and travertine deposition in an active tectonic setting: Insights from the Kamara geothermal area (western Anatolia, Turkey)

    NASA Astrophysics Data System (ADS)

    Brogi, Andrea; Alçiçek, M. Cihat; Yalçıner, Cahit Çağlar; Capezzuoli, Enrico; Liotta, Domenico; Meccheri, Marco; Rimondi, Valentina; Ruggieri, Giovanni; Gandin, Anna; Boschi, Chiara; Büyüksaraç, Aydin; Alçiçek, Hülya; Bülbül, Ali; Baykara, Mehmet Oruç; Shen, Chuan-Chou

    2016-06-01

    Coexistence of thermal springs, travertine deposits and tectonic activity is a recurring feature for most geothermal areas. Although such a certainty, their relationships are debated mainly addressing on the role of the tectonic activity in triggering and controlling fluids flow and travertine deposition. In this paper, we present the results of an integrated study carried out in a geothermal area located in western Anatolia (Turkey), nearby the well-known Pamukkale area (Denizli Basin). Our study focused on the relationships among hydrothermal fluids circulation, travertine deposition and tectonic activity, with particular emphasis on the role of faults in controlling fluids upwelling, thermal springs location and deposition of travertine masses. New field mapping and structural/kinematics analyses allowed us to recognize two main faults systems (NW- and NE-trending), framed in the Neogene-Quaternary extensional tectonic evolution of western Anatolia. A geo-radar (GPR) prospection was also provided in a key-area, permitting us to reconstruct a buried fault zone and its relationships with the development of a fissure-ridge travertine deposit (Kamara fissure-ridge). The integration among structural and geophysical studies, fluids inclusion, geochemical, isotopic data and 230 Th/238 U radiometric age determination on travertine deposits, depict the characteristics of the geothermal fluids and their pathway, up to the surface. Hydrological and seismological data have been also taken in account to investigate the relation between local seismicity and fluid upwelling. As a main conclusion we found strict relationships among tectonic activity, earthquakes occurrence, and variation of the physical/chemical features of the hydrothermal fluids, presently exploited at depth, or flowing out in thermal springs. In the same way, we underline the tectonic role in controlling the travertine deposition, making travertine (mainly banded travertine) a useful proxy to reconstruct the

  18. Fluidized-bed combustion

    SciTech Connect

    Botros, P E

    1990-04-01

    This report describes the activities of the Morgantown Energy Technology Center's research and development program in fluidized-bed combustion from October 1, 1987, to September 30, 1989. The Department of Energy program involves atmospheric and pressurized systems. Demonstrations of industrial-scale atmospheric systems are being completed, and smaller boilers are being explored. These systems include vortex, multi-solid, spouted, dual-sided, air-cooled, pulsed, and waste-fired fluidized-beds. Combustion of low-rank coal, components, and erosion are being studied. In pressurized combustion, first-generation, combined-cycle power plants are being tested, and second-generation, advanced-cycle systems are being designed and cost evaluated. Research in coal devolatilization, metal wastage, tube corrosion, and fluidization also supports this area. 52 refs., 24 figs., 3 tabs.

  19. Resistance exercise-induced fluid shifts: change in active muscle size and plasma volume

    NASA Technical Reports Server (NTRS)

    Ploutz-Snyder, L. L.; Convertino, V. A.; Dudley, G. A.

    1995-01-01

    The purpose of this study was to test the hypothesis that the reduction in plasma volume (PV) induced by resistance exercise reflects fluid loss to the extravascular space and subsequently selective increase in cross-sectional area (CSA) of active but not inactive skeletal muscle. We compared changes in active and inactive muscle CSA and PV after barbell squat exercise. Magnetic resonance imaging (MRI) was used to quantify muscle involvement in exercise and to determine CSA of muscle groups or individual muscles [vasti (VS), adductor (Add), hamstring (Ham), and rectus femoris (RF)]. Muscle involvement in exercise was determined using exercise-induced contrast shift in spin-spin relaxation time (T2)-weighted MR images immediately postexercise. Alterations in muscle size were based on the mean CSA of individual slices. Hematocrit, hemoglobin, and Evans blue dye were used to estimate changes in PV. Muscle CSA and PV data were obtained preexercise and immediately postexercise and 15 and 45 min thereafter. A hierarchy of muscle involvement in exercise was found such that VS > Add > Ham > RF, with the Ham and RF showing essentially no involvement. CSA of the VS and Add muscle groups were increased 10 and 5%, respectively, immediately after exercise in each thigh with no changes in Ham and RF CSA. PV was decreased 22% immediately following exercise. The absolute loss of PV was correlated (r2 = 0.75) with absolute increase in muscle CSA immediately postexercise, supporting the notion that increased muscle size after resistance exercise reflects primarily fluid movement from the vascular space into active but not inactive muscle.

  20. Succinate dehydrogenase activity in cultured human skin fibroblasts and amniotic fluid cells. A methodological study.

    PubMed

    Hansen, T L; Andersen, H

    1983-01-01

    Through a methodological evaluation, reliable histochemical and biochemical methods for succinate dehydrogenase activity in cultured human skin fibroblasts and amniotic fluid cells were developed. The histochemical method includes a cleaning of the cultured cells in 1 mM malonate in 0.9% NaCl, air-drying and fixation in acetone (5 min at -20 degrees C), coating of cells with CoQ10 (0.2 mg/ml in ether/acetone) and incubation for 1 h at 37 degrees C in 50 mM succinate and 0.5 mg/ml Nitro BT in 200 mM phosphate buffer, pH 7.6 PMS as an intermediate electron carrier was found inferior to exogenous CoQ10. Both types of cells exhibit equal activity. In the biochemical method homogenizing was performed in 50 mM Tris-HCl buffer, pH 7.5, and 200 mM sucrose. The standard incubation was 2.0 mM INT and 10 mM succinate in 10 mM Tris-HCl buffer, pH 7.5 for 1 h at 37 degrees C. The apparent Km values for INT and succinate were estimated to 0.39 mM and 0.13 mM, respectively, while I0.5 for malonate was 0.46 mM. Activity in amniotic fluid cells was 18.1 pkat/mg protein and in human skin fibroblasts 20.3 pkat/mg protein. Specificity of the methods was tested by use of a Chinese hamster fibroblast strain B9 known to be succinate dehydrogenase deficient in addition to various control experiments. Congruent results were obtained with the two methods.

  1. Chromogranin A immunoreactivity in human cerebrospinal fluid: properties, relationship to noradrenergic neuronal activity, and variation in neurologic disease.

    PubMed

    O'Connor, D T; Cervenka, J H; Stone, R A; Parmer, R J; Franco-Bourland, R E; Madrazo, I; Langlais, P J

    1993-10-01

    Although measurement of chromogranin A in the bloodstream is of value in sympathoadrenal investigations, little is systematically known about chromogranin A in cerebrospinal fluid, despite substantial knowledge about its occurrence and distribution in brain. We therefore applied a homologous human chromogranin A radioimmunoassay to cerebrospinal fluid, in order to evaluate the properties and stability of cerebrospinal fluid chomogranin A, as well as its relationship to central noradrenergic neuronal activity, to peripheral (plasma) chromogranin A, and to disease states such as hypertension, renal failure and Parkinsonism. Authentic, physically stable chromogranin A immunoreactivity was found in cerebrospinal fluid (at 37-146 ng/ml; mean, 87.0 +/- 6.0 ng/ml in healthy subjects), and several lines of evidence (including 3.39 +/- 0.27-fold higher chromogranin A in cerebrospinal fluid than in plasma) indicated that it originated from a local central nervous system source, rather than the periphery. Cerebrospinal fluid chromogranin A values were not influenced by administration of effective antihypertensive doses of clonidine or propranolol, and were not related to the cerebrospinal fluid concentrations of norepinephrine, methoxyhydroxyphenylglycol, or dopamine-beta-hydroxylase; thus, cerebrospinal fluid chromogranin A was not closely linked to biochemical or pharmacologic indices of central noradrenergic neuronal activity. Cerebrospinal fluid chromogranin A was not changed (P > 0.1) in essential hypertension (84.2 +/- 14.0 ng/ml) or renal failure (72.2 +/- 13.4 ng/ml), despite a marked (7.1-fold; P < 0.001) increase in plasma chromogranin A in renal failure, and a modest (1.5-fold; P = 0.004) increase in plasma chromogranin A in essential hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Bacillus cereus in free-stall bedding.

    PubMed

    Magnusson, M; Svensson, B; Kolstrup, C; Christiansson, A

    2007-12-01

    To increase the understanding of how different factors affect the bacterial growth in deep sawdust beds for dairy cattle, the microbiological status of Bacillus cereus and coliforms in deep sawdust-bedded free stalls was investigated over two 14-d periods on one farm. High counts of B. cereus and coliforms were found in the entire beds. On average, 4.1 log(10) B. cereus spores, 5.5 log(10) B. cereus, and 6.7 log(10) coliforms per gram of bedding could be found in the upper layers of the sawdust likely to be in contact with the cows' udders. The highest counts of B. cereus spores, B. cereus, and coliforms were found in the bedding before fresh bedding was added, and the lowest immediately afterwards. Different factors of importance for the growth of B. cereus in the bedding material were explored in laboratory tests. These were found to be the type of bedding, pH, and the type and availability of nutrients. Alternative bedding material such as peat and mixtures of peat and sawdust inhibited the bacterial growth of B. cereus. The extent of growth of B. cereus in the sawdust was increased in a dose-dependent manner by the availability of feces. Urine added to different bedding material raised the pH and also led to bacterial growth of B. cereus in the peat. In sawdust, a dry matter content greater than 70% was needed to lower the water activity to 0.95, which is needed to inhibit the growth of B. cereus. In an attempt to reduce the bacterial growth of B. cereus and coliforms in deep sawdust beds on the farm, the effect of giving bedding daily or a full replacement of the beds was studied. The spore count of B. cereus in the back part of the free stalls before fresh bedding was added was 0.9 log units lower in stalls given daily bedding than in stalls given bedding twice weekly. No effect on coliform counts was found. Replacement of the entire sawdust bedding had an effect for a short period, but by 1 to 2 mo after replacement, the counts of B. cereus spores in the

  3. Comparison of human immunodeficiency virus type 1-specific inhibitory activities in saliva and other human mucosal fluids.

    PubMed

    Kazmi, Shamim H; Naglik, Julian R; Sweet, Simon P; Evans, Robert W; O'Shea, Siobhan; Banatvala, Jangu E; Challacombe, Stephen J

    2006-10-01

    Several human mucosal fluids are known to possess an innate ability to inhibit human immunodeficiency virus type 1 (HIV-1) infection and replication in vitro. This study compared the HIV-1 inhibitory activities of several mucosal fluids, whole, submandibular/sublingual (sm/sl), and parotid saliva, breast milk, colostrum, seminal plasma, and cervicovaginal secretions, from HIV-1-seronegative donors by using a 3-day microtiter infection assay. A wide range of HIV-1 inhibitory activity was exhibited in all mucosal fluids tested, with some donors exhibiting high levels of activity while others showed significantly lower levels. Colostrum, whole milk, and whole saliva possessed the highest levels of anti-HIV-1 activity, seminal fluid, cervicovaginal secretions, and sm/sl exhibited moderate levels, and parotid saliva consistently demonstrated the lowest levels of HIV-1 inhibition. Fast protein liquid chromatography gel filtration studies revealed the presence of at least three distinct peaks of inhibitory activity against HIV-1 in saliva and breast milk. Incubation of unfractionated and fractionated whole saliva with antibodies raised against human lactoferrin (hLf), secretory leukocyte protease inhibitor (SLPI), and, to a lesser extent, MG2 (high-molecular-weight mucinous glycoprotein) reduced the HIV-1 inhibitory activity significantly. The results suggest that hLf and SLPI are two key components responsible for HIV-1 inhibitory activity in different mucosal secretions. The variation in HIV inhibitory activity between the fluids and between individuals suggests that there may be major differences in susceptibility to HIV infection depending both on the individual and on the mucosal fluid involved.

  4. Associations between PON1 enzyme activities in human ovarian follicular fluid and serum specimens

    PubMed Central

    Kim, Keewan; Fujimoto, Victor Y.; Browne, Richard W.

    2017-01-01

    The importance of high-density lipoprotein (HDL) particle components to reproduction is increasingly recognized, including the constituent paraoxonase 1 (PON1). However, the reliability characteristics of PON1 enzymes in ovarian follicular fluid (FF) as biomarkers for clinical and epidemiologic studies have not been described. Therefore, we characterized PON1 enzymes in FF and serum and assessed the impact of the PON1 Q192R polymorphism on associations between enzyme activities in two compartments. We also evaluated associations between HDL particle size and enzyme activities. We collected FF and serum from 171 women undergoing in vitro fertilization. PON1 activities were measured as paraoxonase and arylesterase activities, and HDL particle size was determined by 1H NMR spectrometry. Reliability indices for PON1 activities were characterized and we evaluated HDL particle sizes as predictors of PON1 enzyme activities. We found that PON1 enzyme activities were correlated between compartments, but higher in serum than in FF. For FF, the index of individuality (II) was low and the coefficient of variation (CV%) was high for paraoxonase activity overall (0.12 and 11.51%, respectively). However, IIs increased (0.33–1.30) and CV%s decreased (5.58%-8.52%) when stratified by PON1 Q192R phenotype. The intraclass correlation coefficient (ICC) for FF paraoxonase activity was high overall (0.89) but decreased when stratified by PON1 Q192R phenotype (0.43–0.75). We found similar, although more modest, patterns for FF arylesterase activity. For enzyme activities in serum, ICCs were close to 1.00 across all phenotypes. Additionally, different HDL particle sizes predicted PON1 enzyme activities according to PON1 Q192R phenotype. Overall, stratification by PON1 Q192R phenotype improved the reliability characteristics of FF PON1 enzymes as biomarkers for use in clinical investigations but diminished usefulness for epidemiologic studies. Thus, we recommend stratification by PON1 Q

  5. A fully resolved fluid-structure-muscle-activation model for esophageal transport

    NASA Astrophysics Data System (ADS)

    Kou, Wenjun; Bhalla, Amneet P. S.; Griffith, Boyce E.; Johnson, Mark; Patankar, Neelesh A.

    2013-11-01

    Esophageal transport is a mechanical and physiological process that transfers the ingested food bolus from the pharynx to the stomach through a multi-layered esophageal tube. The process involves interactions between the bolus, esophageal wall composed of mucosal, circular muscle (CM) and longitudinal muscle (LM) layers, and neurally coordinated muscle activation including CM contraction and LM shortening. In this work, we present a 3D fully-resolved model of esophageal transport based on the immersed boundary method. The model describes the bolus as a Newtonian fluid, the esophageal wall as a multi-layered elastic tube represented by springs and beams, and the muscle activation as a traveling wave of sequential actuation/relaxation of muscle fibers, represented by springs with dynamic rest lengths. Results on intraluminal pressure profile and bolus shape will be shown, which are qualitatively consistent with experimental observations. Effects of activating CM contraction only, LM shortening only or both, for the bolus transport, are studied. A comparison among them can help to identify the role of each type of muscle activation. The support of grant R01 DK56033 and R01 DK079902 from NIH is gratefully acknowledged.

  6. A Randomized Controlled Design Investigating the Effects of Classroom-Based Physical Activity on Children's Fluid Intelligence and Achievement

    ERIC Educational Resources Information Center

    Fedewa, Alicia L.; Ahn, Soyeon; Erwin, Heather; Davis, Matthew C.

    2015-01-01

    Existing literature shows promising effects of physical activity on children's cognitive outcomes. This study assessed via a randomized, controlled design whether additional curricular physical activity during the school day resulted in gains for children's fluid intelligence and standardized achievement outcomes. Participants were children…

  7. Improving sensitivity in chiral supercritical fluid chromatography for analysis of active pharmaceutical ingredients.

    PubMed

    Helmy, Roy; Biba, Mirlinda; Zang, Jia; Mao, Bing; Fogelman, Kimber; Vlachos, Vaso; Hosek, Paul; Welch, Christopher J

    2007-11-01

    Despite its status as the preferred method for routine enantiopurity analysis in pharmaceutical research, supercritical fluid chromatography (SFC) has historically been unsuited for the accurate and precise measurements required for release testing of active pharmaceutical ingredients (APIs) under current good manufacturing processes (cGMPs). Insufficient signal to noise, as compared to HPLC, has heretofore been the major limitation of the chiral SFC approach. We herein describe an investigation into the fundamental limitations and sources of noise in the SFC approach, identifying thermal, electronic, and mechanical sources of noise within the flow cell as key parameters contributing to reduced sensitivity. A variety of instrument modifications are explored, ultimately leading to the development of a new and improved flow cell and other instrument modifications that allow suitable sensitivity and accuracy to carry out GMP release testing for enantiopurity analysis using SFC.

  8. Bubble mass center and fluid feedback force fluctuations activated by constant lateral impulse with variable thrust

    NASA Technical Reports Server (NTRS)

    Hung, R. J.; Long, Y. T.

    1995-01-01

    Sloshing dynamics within a partially filled rotating dewar of superfluid helium 2 are investigated in response to constant lateral impulse with variable thrust. The study, including how the rotating bubble of superfluid helium 2 reacts to the constant impulse with variable time period of thrust action in microgravity, how amplitudes of bubble mass center fluctuates with growth and decay of disturbances, and how fluid feedback forces fluctuates in activating on the rotating dewar through the dynamics of sloshing waves are investigated. The numerical computation of sloshing dynamics is based on the non-inertial frame spacecraft bound coordinate with lateral impulses actuating on the rotating dewar in both inertial and non-inertial frames of thrust. Results of the simulations are illustrated.

  9. Alkaline phosphatase activity in gingival crevicular fluid during human orthodontic tooth movement.

    PubMed

    Perinetti, Giuseppe; Paolantonio, Michele; D'Attilio, Michele; D'Archivio, Domenico; Tripodi, Domenico; Femminella, Beatrice; Festa, Felice; Spoto, Giuseppe

    2002-11-01

    Bone remodeling that occurs during orthodontic tooth movement is a biologic process involving an acute inflammatory response in periodontal tissues. A sequence characterized by periods of activation, resorption, reversal, and formation has been recently described as occurring in both tension and compression tooth sites during orthodontic tooth movement. We used a longitudinal design to investigate alkaline phosphatase (ALP) activity in gingival crevicular fluid (GCF) to assess whether it can serve as a diagnostic aid in orthodontics. Sixteen patients (mean age, 15.5 years) participated in the study. The maxillary first molars under treatment served as the test teeth (TT) in each patient; in particular, 1 first molar was to be retracted and hence was considered the distalized molar (DM), whereas the contralateral molar (CM) was included in the fixed orthodontic appliance but was not subjected to the distal forces. The DM antagonist first molar (AM), free from any orthodontic appliance, was used as the baseline control. The GCF around the experimental teeth was harvested from mesial and distal tooth sites immediately before appliance activation, 1 hour after, and weekly over the following 4 weeks. The clinical gingival condition was evaluated at the baseline and at the end of the experimental term. ALP activity was determined spectrophotometrically at 30 degrees C, and the results were expressed as total ALP activity (mUnits/sample). GCF ALP activity was significantly elevated in the DMs and the CMs as compared with the AMs at 1, 2, 3, and 4 weeks; conversely, in the AMs, GCF ALP activity remained at baseline levels throughout the experiment. Moreover, the enzyme activity in the DMs was significantly greater than in the CMs. In the DMs, a significantly greater ALP activity was observed in sites of tension compared with sites of compression. This difference was not seen with the CMs, in which the enzyme activity increased to the same extent in tension and compression

  10. Orbital fluid shear stress promotes osteoblast metabolism, proliferation and alkaline phosphates activity in vitro

    SciTech Connect

    Aisha, M.D.; Nor-Ashikin, M.N.K.; Sharaniza, A.B.R.; Nawawi, H.; Froemming, G.R.A.

    2015-09-10

    Prolonged disuse of the musculoskeletal system is associated with reduced mechanical loading and lack of anabolic stimulus. As a form of mechanical signal, the multidirectional orbital fluid shear stress transmits anabolic signal to bone forming cells in promoting cell differentiation, metabolism and proliferation. Signals are channeled through the cytoskeleton framework, directly modifying gene and protein expression. For that reason, we aimed to study the organization of Normal Human Osteoblast (NHOst) cytoskeleton with regards to orbital fluid shear (OFS) stress. Of special interest were the consequences of cytoskeletal reorganization on NHOst metabolism, proliferation, and osteogenic functional markers. Cells stimulated at 250 RPM in a shaking incubator resulted in the rearrangement of actin and tubulin fibers after 72 h. Orbital shear stress increased NHOst mitochondrial metabolism and proliferation, simultaneously preventing apoptosis. The ratio of RANKL/OPG was reduced, suggesting that orbital shear stress has the potential to inhibit osteoclastogenesis and osteoclast activity. Increase in ALP activity and OCN protein production suggests that stimulation retained osteoblast function. Shear stress possibly generated through actin seemed to hold an anabolic response as osteoblast metabolism and functional markers were enhanced. We hypothesize that by applying orbital shear stress with suitable magnitude and duration as a non-drug anabolic treatment can help improve bone regeneration in prolonged disuse cases. - Highlights: • OFS stress transmits anabolic signals to osteoblasts. • Actin and tubulin fibers are rearranged under OFS stress. • OFS stress increases mitochondrial metabolism and proliferation. • Reduced RANKL/OPG ratio in response to OFS inhibits osteoclastogenesis. • OFS stress prevents apoptosis and stimulates ALP and OCN.

  11. Determination of a suitable parameter field for the active fluid jet polishing process

    NASA Astrophysics Data System (ADS)

    Maurer, Roland; Biskup, Heiko; Trum, Christian; Rascher, Rolf; Wünsche, Christine

    2013-09-01

    In 2012 a well-known company in the field of high precision optics assigned the University of Applied Sciences Deggendorf to determine a suitable parameter field for the active fluid jet polishing (AFJP) process in order to reach a surface accuracy of at least lambda / 5. The active fluid jet polishing is a relatively new and an affordable sub-aperture polishing process. For a fast and precise identification of the parameter field a considered design of experiment is necessary. The available control variables were the rotational speed of the nozzle, the distance between the test object and the jet, the feed rate, the material of the pin inside the nozzle and the material of the test object itself. In order to reach a significant data density on the one hand and to minimize the number of test runs on the other hand a meander shaped tool path was chosen. At each blank nine paths had been driven whereby at each path another parameter combination was picked. Thus with only one test object nine parameter settings may be evaluated. For the automatized analysis of the tracks a software tool was developed. The software evaluates ten sections which orthogonally intersect the nine tracks on the test-lens. The significant measurement parameters per section are the width and the height of each path as well as the surface roughness within the polished tracks. With the aid of these parameters and further statistical evaluations a suitable parameter field for the goal to find a constant and predictable removal spot was determined. Furthermore up to now over 60 test runs have been successfully finished with nine parameter combinations in each case. As a consequence a test evaluation by hand would be very time-consuming and the software facilitates it dramatically.

  12. Circulating extracellular proteasome in the cerebrospinal fluid: a study on concentration and proteolytic activity.

    PubMed

    Mueller, Oliver; Anlasik, Timur; Wiedemann, Jonas; Thomassen, Jan; Wohlschlaeger, Jeremias; Hagel, Vincent; Keyvani, Kathy; Schwieger, Isabel; Dahlmann, Burkhardt; Sure, Ulrich; Sixt, Stephan Urs

    2012-03-01

    Alterations of the intracellular ubiquitin-proteasome pathway are found in neurodegenerative and inflammatory disorders of the central nervous system, as well as in its malignancies. Inhibitory substrates of the proteasomes represent promising approaches to control autoimmune inflammations and induction of apoptosis in cancer cells. Extracellular circulating proteasomes are positively correlated to outcome prognosis in hematogenic neoplasias and the outcome in critically ill patients. Previously, we reported raised levels of proteolytic active 20S proteasomes in the extracellular alveolar space in patients with acute respiratory distress syndrome (ARDS). For the cerebrospinal fluid, we assumed that extracellular circulating proteasomes with enzymatic activity can be found, too. Cerebrospinal fluid (CSF) samples of twenty-six patients (14 females, 12 males), who underwent diagnostic spinal myelography, were analyzed for leukocyte cell count, total protein content, lactate and interleukine-6 (Il-6) concentrations. CSF samples were analyzed for concentration and enzymatic activity of extracellular 20S proteasomes (fluorescenic substrate cleavage; femtokatal). Blood samples were analyzed with respect to concentration of extracellular circulating proteasomes. Choroidal plexus was harvested at autopsies and examined with immunoelectron microscopy (EM) for identification of possible transportation mechanisms. Statistical analysis was performed using SPSS (18.0.3). In all patients, extracellular proteasome was found in the CSF. The mean concentration was 24.6 ng/ml. Enzymatic activity of the 20S subunits of proteasomes was positively identified by the fluorescenic subtrate cleavage at a mean of 8.5 fkat/ml. Concentrations of extracellular proteasomes in the CSF, total protein content and Il-6 were uncorrelated. Immunoelectron microscopy revealed merging vesicles of proteasomes with the outer cell membrane suggestive of an exozytic transport mechanism. For the first time

  13. Comparison of Antibodies with Amylase Activity from Cerebrospinal Fluid and Serum of Patients with Multiple Sclerosis

    PubMed Central

    Doronin, Vasilii B.; Parkhomenko, Taisiya A.; Castellazzi, Massimiliano; Cesnik, Edward; Buneva, Valentina N.; Granieri, Enrico; Nevinsky, Georgy A.

    2016-01-01

    We have recently shown that IgGs from serum and cerebrospinal fluid (CSF) of MS patients are active in hydrolysis of DNA and myelin basic protein. According to literature data, anti-DNA and anti-MBP abzymes may promote important neuropathologic mechanisms in this chronic inflammatory disorder and in MS pathogenesis development. At the same time, the involvement of antibodies with amylase activity in the pathogenesis of any autoimmune disease has not yet been identified. Electrophoretically and immunologically homogeneous IgGs were obtained by a sequential affinity chromatography of the CSF proteins on protein G-Sepharose and FPLC gel filtration. We are able to present the first unpredictable evidence showing that IgGs from CSF possess amylase activity and efficiently hydrolyze maltoheptaose; their average specific Ab activity is ~30-fold higher than that of antibodies from sera of the same MS patients. Specific average RA (SAA) for IgGs from healthy volunteers was approximately ~1000 lower than that for MS patients. In addition, it was shown that a relative SAA of total proteins of CSF (including Abs) ~15-fold lower than that for purified IgGs, while the relative SAA of the total sera protein is higher than that of sera IgGs by a factor of 1033. This result speaks in favor of the fact that amylolytic activity of CSF proteins is mainly caused by the activity of amylase abzymes. One cannot exclude, that amylase abzymes of CSF can play a, as yet unknown, role in the pathogenesis of MS. Some possible reasons of these findings are discussed. PMID:27196086

  14. Nonchromatographic affinity precipitation method for the purification of bivalently active pharmaceutical antibodies from biological fluids.

    PubMed

    Handlogten, Michael W; Stefanick, Jared F; Alves, Nathan J; Bilgicer, Basar

    2013-05-21

    This Article describes an affinity-based precipitation method for the rapid and nonchromatographic purification of bivalently active monoclonal antibodies by combining the selectivity of affinity chromatography with the simplicity of salt-induced precipitation. This procedure involves (i) precipitation of proteins heavier than immunoglobulins with ammonium sulfate; (ii) formation and selective precipitation of cyclic antibody complexes created by binding to trivalent haptens specific for the antibody; and (iii) membrane filtration of the solubilized antibody pellet to remove the trivalent hapten from the purified antibody. We applied this technique to the purification of two pharmaceutical antibodies, trastuzumab and rituximab, by synthesizing trivalent haptens specific for each antibody. Using this method, we were able to purify both antibodies from typical contaminants including CHO cell conditioned media, ascites fluid, DNA, and other antibodies with yields >85% and with >95% purity. The purified antibodies displayed native binding levels to cell lines expressing the target proteins demonstrating that the affinity-based precipitation method did not adversely affect the antibodies. The selectivity of the affinity-based precipitation method for bivalently active antibodies was established by purifying trastuzumab from a solution containing both active and chemically denatured trastuzumab. Prior to purification, the solutions displayed 20-76% reduction in binding activity, and after purification, native binding activity was restored, indicating that the purified product contained only bivalently active antibody. Taken together, the affinity-based precipitation method provides a rapid and straightforward process for the purification of antibodies with the potential to improve product quality while decreasing the purification costs at both the lab and the industrial scale.

  15. Chemokines in the cerebrospinal fluid of patients with active and stable relapsing-remitting multiple sclerosis.

    PubMed

    Moreira, M A; Souza, A L S; Lana-Peixoto, M A; Teixeira, M M; Teixeira, A L

    2006-04-01

    Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the human central nervous system. Although its etiology is unknown, the accumulation and activation of mononuclear cells in the central nervous system are crucial to its pathogenesis. Chemokines have been proposed to play a major role in the recruitment and activation of leukocytes in inflammatory sites. They are divided into subfamilies on the basis of the location of conserved cysteine residues. We determined the levels of some CC and CXC chemokines in the cerebrospinal fluid (CSF) of 23 relapsing-remitting MS patients under interferon-ss-1a therapy and 16 control subjects using ELISA. MS patients were categorized as having active or stable disease. CXCL10 was significantly increased in the CSF of active MS patients (mean +/- SEM, 369.5 +/- 69.3 pg/mL) when compared with controls (178.5 +/- 29.1 pg/mL, P < 0.05). CSF levels of CCL2 were significantly lower in active MS (144.7 +/- 14.4 pg/mL) than in controls (237.1 +/- 16.4 pg/mL, P < 0.01). There was no difference in the concentration of CCL2 and CXCL10 between patients with stable MS and controls. CCL5 was not detectable in the CSF of most patients or controls. The qualitative and quantitative differences of chemokines in CSF during relapses of MS suggest that they may be useful as a marker of disease activity and of the mechanisms involved in the pathogenesis of the disease.

  16. Operation of Packed-Bed Reactors Studied in Microgravity

    NASA Technical Reports Server (NTRS)

    Motil, Brian J.; Balakotaiah, Vemuri

    2004-01-01

    The operation of a packed bed reactor (PBR) involves gas and liquid flowing simultaneously through a fixed-bed of solid particles. Depending on the application, the particles can be various shapes and sizes but are generally designed to force the two fluid phases through a tortuous route of narrow channels connecting the interstitial space. The PBR is the most common type of reactor in industry because it provides for intimate contact and high rates of transport between the phases needed to sustain chemical or biological reactions. The packing may also serve as either a catalyst or as a support for growing biological material. Furthermore, this type of reactor is relatively compact and requires minimal power to operate. This makes it an excellent candidate for unit operations in support of long-duration human space activities.

  17. Fluid Shear Stress Regulates the Invasive Potential of Glioma Cells via Modulation of Migratory Activity and Matrix Metalloproteinase Expression

    PubMed Central

    Qazi, Henry; Shi, Zhong-Dong; Tarbell, John M.

    2011-01-01

    Background Glioma cells are exposed to elevated interstitial fluid flow during the onset of angiogenesis, at the tumor periphery while invading normal parenchyma, within white matter tracts, and during vascular normalization therapy. Glioma cell lines that have been exposed to fluid flow forces in vivo have much lower invasive potentials than in vitro cell motility assays without flow would indicate. Methodology/Principal Findings A 3D Modified Boyden chamber (Darcy flow through collagen/cell suspension) model was designed to mimic the fluid dynamic microenvironment to study the effects of fluid shear stress on the migratory activity of glioma cells. Novel methods for gel compaction and isolation of chemotactic migration from flow stimulation were utilized for three glioma cell lines: U87, CNS-1, and U251. All physiologic levels of fluid shear stress suppressed the migratory activity of U87 and CNS-1 cell lines. U251 motility remained unaltered within the 3D interstitial flow model. Matrix Metalloproteinase (MMP) inhibition experiments and assays demonstrated that the glioma cells depended on MMP activity to invade, and suppression in motility correlated with downregulation of MMP-1 and MMP-2 levels. This was confirmed by RT-PCR and with the aid of MMP-1 and MMP-2 shRNA constructs. Conclusions/Significance Fluid shear stress in the tumor microenvironment may explain reduced glioma invasion through modulation of cell motility and MMP levels. The flow-induced migration trends were consistent with reported invasive potentials of implanted gliomas. The models developed for this study imply that flow-modulated motility involves mechanotransduction of fluid shear stress affecting MMP activation and expression. These models should be useful for the continued study of interstitial flow effects on processes that affect tumor progression. PMID:21637818

  18. Inspection and analysis of the walls of fluid filled tubes by active electrolocation: a biomimetic approach

    NASA Astrophysics Data System (ADS)

    Gottwald, Martin; Mayekar, Kavita; Reiswich, Vladislav; Bousack, Herbert; Damalla, Deepak; Biswas, Shubham; Metzen, Michael G.; von der Emde, Gerhard

    2011-04-01

    During their nocturnal activity period, weakly electric fish employ a process called "active electrolocation" for navigation and object detection. They discharge an electric organ in their tail, which emits electrical current pulses, called electric organ discharges (EOD). Local EODs are sensed by arrays of electroreceptors in the fish's skin, which respond to modulations of the signal caused by nearby objects. Fish thus gain information about the size, shape, complex impedance and distance of objects. Inspired by these remarkable capabilities, we have designed technical sensor systems which employ active electrolocation to detect and analyse the walls of small, fluid filled pipes. Our sensor systems emit pulsed electrical signals into the conducting medium and simultaneously sense local current densities with an array of electrodes. Sensors can be designed which (i) analyse the tube wall, (ii) detect and localize material faults, (iii) identify wall inclusions or objects blocking the tube (iv) and find leakages. Here, we present first experiments and FEM simulations on the optimal sensor arrangement for different types of sensor systems and different types of tubes. In addition, different methods for sensor read-out and signal processing are compared. Our biomimetic sensor systems promise to be relatively insensitive to environmental disturbances such as heat, pressure, turbidity or muddiness. They could be used in a wide range of tubes and pipes including water pipes, hydraulic systems, and biological systems. Medical applications include catheter based sensors which inspect blood vessels, urethras and similar ducts in the human body.

  19. Semi-active engine mount design using auxiliary magneto-rheological fluid compliance chamber

    NASA Astrophysics Data System (ADS)

    Mansour, H.; Arzanpour, S.; Golnaraghi, M. F.; Parameswaran, A. M.

    2011-03-01

    Engine mounts are used in the automotive industry to isolate engine and chassis by reducing the noise and vibration imposed from one to the other. This paper describes modelling, simulation and design of a semi-active engine mount that is designed specifically to address the complicated vibration pattern of variable displacement engines (VDE). The ideal isolation for VDE requires the stiffness to be switchable upon cylinder activation/deactivation operating modes. In order to have a modular design, the same hydraulic engine mount components are maintained and a novel auxiliary magneto-rheological (MR) fluid chamber is developed and retrofitted inside the pumping chamber. The new compliance chamber is a controllable pressure regulator, which can effectively alter the dynamic performance of the mount. Switching between different modes happens by turning the electrical current to the MR chamber magnetic coil on and off. A model has been developed for the passive hydraulic mount and then it is extended to include the MR auxiliary chamber as well. A proof-of-concept prototype of the design has been fabricated which validates the mathematical model. The results demonstrate unique capability of the developed semi-active mount to be used for VDE application.

  20. A semi-active control suspension system for railway vehicles with magnetorheological fluid dampers

    NASA Astrophysics Data System (ADS)

    Wei, Xiukun; Zhu, Ming; Jia, Limin

    2016-07-01

    The high-speed train has achieved great progress in the last decades. It is one of the most important modes of transportation between cities. With the rapid development of the high-speed train, its safety issue is paid much more attention than ever before. To improve the stability of the vehicle with high speed, extra dampers (i.e. anti-hunting damper) are used in the traditional bogies with passive suspension system. However, the curving performance of the vehicle is undermined due to the extra lateral force generated by the dampers. The active suspension systems proposed in the last decades attempt to solve the vehicle steering issue. However, the active suspension systems need extra actuators driven by electrical power or hydraulic power. There are some implementation and even safety issues which are not easy to be overcome. In this paper, an innovative semi-active controlled lateral suspension system for railway vehicles is proposed. Four magnetorheological fluid dampers are fixed to the primary suspension system of each bogie. They are controlled by online controllers for enhancing the running stability on the straight track line on the one hand and further improving the curving performance by controlling the damper force on the other hand. Two control strategies are proposed in the light of the pure rolling concept. The effectiveness of the proposed strategies is demonstrated by SIMPACK and Matlab co-simulation for a full railway vehicle with two conventional bogies.

  1. Embryo as an active granular fluid: stress-coordinated cellular constriction chains

    NASA Astrophysics Data System (ADS)

    Gao, Guo-Jie Jason; Holcomb, Michael C.; Thomas, Jeffrey H.; Blawzdziewicz, Jerzy

    2016-10-01

    Mechanical stress plays an intricate role in gene expression in individual cells and sculpting of developing tissues. However, systematic methods of studying how mechanical stress and feedback help to harmonize cellular activities within a tissue have yet to be developed. Motivated by our observation of the cellular constriction chains (CCCs) during the initial phase of ventral furrow formation in the Drosophila melanogaster embryo, we propose an active granular fluid (AGF) model that provides valuable insights into cellular coordination in the apical constriction process. In our model, cells are treated as circular particles connected by a predefined force network, and they undergo a random constriction process in which the particle constriction probability P is a function of the stress exerted on the particle by its neighbors. We find that when P favors tensile stress, constricted particles tend to form chain-like structures. In contrast, constricted particles tend to form compact clusters when P favors compression. A remarkable similarity of constricted-particle chains and CCCs observed in vivo provides indirect evidence that tensile-stress feedback coordinates the apical constriction activity. Our particle-based AGF model will be useful in analyzing mechanical feedback effects in a wide variety of morphogenesis and organogenesis phenomena.

  2. Cervicovaginal fluid and semen block the microbicidal activity of hydrogen peroxide produced by vaginal lactobacilli

    PubMed Central

    2010-01-01

    Background H2O2 produced by vaginal lactobacilli is believed to protect against infection, and H2O2-producing lactobacilli inactivate pathogens in vitro in protein-free salt solution. However, cervicovaginal fluid (CVF) and semen have significant H2O2-blocking activity. Methods We measured the H2O2 concentration of CVF and the H2O2-blocking activity of CVF and semen using fluorescence and in vitro bacterial-exposure experiments. Results The mean H2O2 measured in fully aerobic CVF was 23 ± 5 μM; however, 50 μM H2O2 in salt solution showed no in vitro inactivation of HSV-2, Neisseria gonorrhoeae, Hemophilus ducreyii, or any of six BV-associated bacteria. CVF reduced 1 mM added H2O2 to an undetectable level, while semen reduced 10 mM added H2O2 to undetectable. Moreover, the addition of just 1% CVF supernatant abolished in vitro pathogen-inactivation by H2O2-producing lactobacilli. Conclusions Given the H2O2-blocking activity of CVF and semen, it is implausible that H2O2-production by vaginal lactobacilli is a significant mechanism of protection in vivo. PMID:20482854

  3. Fluid imbalance

    MedlinePlus

    ... up in the body. This is called fluid overload (volume overload). This can lead to edema (excess fluid in ... Water imbalance; Fluid imbalance - dehydration; Fluid buildup; Fluid overload; Volume overload; Loss of fluids; Edema - fluid imbalance; ...

  4. Fluidized bed heat treating system

    DOEpatents

    Ripley, Edward B; Pfennigwerth, Glenn L

    2014-05-06

    Systems for heat treating materials are presented. The systems typically involve a fluidized bed that contains granulated heat treating material. In some embodiments a fluid, such as an inert gas, is flowed through the granulated heat treating medium, which homogenizes the temperature of the heat treating medium. In some embodiments the fluid may be heated in a heating vessel and flowed into the process chamber where the fluid is then flowed through the granulated heat treating medium. In some embodiments the heat treating material may be liquid or granulated heat treating material and the heat treating material may be circulated through a heating vessel into a process chamber where the heat treating material contacts the material to be heat treated. Microwave energy may be used to provide the source of heat for heat treating systems.

  5. RANTES and Chemotactic Activity in Synovial Fluids From Patients With Rheumatoid Arthritis and Osteoarthritis

    PubMed Central

    Stanczyk, Joanna; Kowalski, Marek L.; Grzegorczyk, Janina; Szkudlinska, Barbara; Jarzebska, Marzanna; Marciniak, Marek; Synder, Marek

    2005-01-01

    A massive accumulation of inflammatory cells in synovial tissues is a major pathological feature of rheumatoid arthritis (RA). Neutrophiles dominate synovial fluid while rheumatoid synovium is infiltrated with mononuclear cells. Mechanisms regulating influx of particular subpopulations of leukocytes into articular cavity and synovium compartment are not completely defined. An increasing amount of data supports a crucial role of a C-C chemokine RANTES in the RA pathogenesis. Our objective is to evaluate chemotactic activity for neutrophils (NCA), lymphocytes (LCA), and monocytes (MoCA) in SFs obtained from patients with RA and osteoarthritis (OA). We also aimed to characterise the relation between chemotactic activity, RANTES, and percentage distribution of leukocytes in SF. SFs from 11 patients with RA and 6 with OA were included in the study. Modified microchamber Boyden method was employed to assess chemotactic activity. Cytological and biochemical analysis of SF was performed. RANTES was measured with ELISA. Rheumatoid SFs were rich in cells with predominance of neutrophiles while osteoarthritic fluids were lymphocytic. RA SFs were also characterised by increased lactoferrin level. Both NCA and LCA were higher in SF from patients with RA (62 ± 12 and 24 ± 6 cells/HPF, resp) as compared to patients with OA (23 ± 6; P < .05 and 6 ± 2 cells/HPF; P < 0.05). The chemoattractive effect of RA SF was more pronounced on neutrophiles than on lymphocytes. RA SF expressed high RANTES levels (145 ± 36 pg/mL), while OA SF was characterised by only trace amount of this chemokine (2 ± 1 pg/mL). We found positive correlation of RANTES with chemotactic activity for mononuclear cells (LCA+MoCA; R = 0.61; P < .05). Surprisingly, RANTES correlated also positively with neutrophiles number (R = 0.77; P < 0.001). Rheumatoid SF possesses strong chemotactic potency for leukocytes. RANTES is overexpressed in RA SF and is a potential mediator influencing intensity and composition

  6. Flow cytometric approach to human polymorphonuclear leukocyte activation induced by gingival crevicular fluid in periodontal disease.

    PubMed

    Biselli, R; Ferlini, C; Di Murro, C; Paolantonio, M; Fattorossi, A

    1995-08-01

    In gingival pockets of patients with periodontal disease, polymorphonuclear leukocytes (PMN) are in contact with a peculiar exudate, the gingival crevicular fluid (GCF). Because of the pivotal role played by PMN in periodontal disease, we evaluated the ability of GCF in modulating normal human PMN. GCF was obtained from two gingival sites with severe periodontitis (SP) and two gingival sites with only mild periodontitis (MP) in 12 patients. Purified PMN were exposed to GCF from SP and MP sites and, as a control, to sterile culture medium. GCF activity was evaluated by monitoring the modulation of membrane molecules relevant to cell function. Compared to control medium, GCF from SP and MP sites was able to induce an activation status in PMN evidenced by an increased CD11b (62 +/- 9% and 28 +/- 7%, respectively) and f-Met-Leu-Phe (56 +/- 5% and 31 +/- 7%, respectively) receptor expression, with a concomitant reduction of CD62L expression (56 +/- 8% and 23 +/- 7%, respectively). Thus, reflecting the clinical status, GCF from SP sites was significantly more efficient in affecting PMN than GCF from MP sites. Cell size modifications, evaluated as an additional indicator of PMN activation, were consistent with membrane molecule modulation. The difference in PMN-activating capacity between SP and MP was abrogated by the successful completion of an appropriate periodontal therapy that dramatically improved clinical status. This is the first direct demonstration that GCF from periodontitis has the capacity to activate normal resting PMN and that this capacity reflects the magnitude of the inflammatory process that takes place in the gingiva.

  7. Factors in cerebrospinal fluid from goats that affect sleep and activity in rats*

    PubMed Central

    Fencl, V.; Koski, G.; Pappenheimer, J. R.

    1971-01-01

    1. Intraventricular infusion in the rat of 0·1 ml. cerebrospinal fluid (c.s.f.) from sleep-deprived goats increases the duration of sleep (measured by e.e.g.) and decreases locomotor activity (measured photo-electrically) for at least 6 hr subsequent to the infusion. Subarachnoid infusions are ineffective. 2. C.s.f. from control and sleep-deprived goats was fractionated by ultrafiltration through molecular sieves. The sleep-promoting Factor S is found in the low molecular weight fraction (mol. wt. < 500) of c.s.f. from sleep-deprived but not from control goats. 3. The concentration of Factor S in c.s.f. increases progressively during the first 48 hr of sleep deprivation. 4. The sleep promoting effects of Factor S cannot be duplicated by serotonin, 4-OH-butyrate, butyrolactone, GABA (γ-amino butyric acid), glutamic acid or 3′,5′-cyclic AMP when these substances are added to control fluids in concentrations up to 10 times greater than those found in normal c.s.f. 5. Intraventricular or subarchnoid infusion in the rat of 0·1 ml. proteinfree c.s.f. containing molecules in the mol. wt. range of 500-10,000 at 10-30 × normal concentration causes hyperactivity which persists for several days and nights following the infusion. The excitatory material, probably a peptide, is present in c.s.f. from both control and sleep-deprived goats. 6. The properties of Factor S suggest that it may play a role in the normal regulation of sleep and wakefulness. PMID:4327693

  8. Rivesville multicell fluidized bed boiler

    SciTech Connect

    Not Available

    1981-03-01

    One objective of the experimental MFB at Rivesville, WV, was the evaluation of alternate feed systems for injecting coal and limestone into a fluidized bed. A continuous, uniform feed flow to the fluid bed is essential in order to maintain stable operations. The feed system originally installed on the MFB was a gravity feed system with an air assist to help overcome the back pressure created by the fluid bed. The system contained belt, vibrating, and rotary feeders which have been proven adequate in other material handling applications. This system, while usable, had several operational and feeding problems during the MFB testing. A major portion of these problems occurred because the coal and limestone feed control points - a belt feeder and rotary feeder, respectively - were pressurized in the air assist system. These control points were not designed for pressurized service. An alternate feed system which could accept feed from the two control points, split the feed into six equal parts and eliminate the problems of the pressurized system was sought. An alternate feed system designed and built by the Fuller Company was installed and tested at the Rivesville facility. Fuller feed systems were installed on the north and south side of C cell at the Rivesville facility. The systems were designed to handle 10,000 lb/hr of coal and limestone apiece. The systems were installed in late 1979 and evaluated from December 1979 to December 1980. During this time period, nearly 1000 h of operating time was accumulated on each system.

  9. Active Path Selection of Fluid Microcapsules in Artificial Blood Vessel by Acoustic Radiation Force

    NASA Astrophysics Data System (ADS)

    Masuda, Kohji; Muramatsu, Yusuke; Ueda, Sawami; Nakamoto, Ryusuke; Nakayashiki, Yusuke; Ishihara, Ken

    2009-07-01

    Micrometer-sized microcapsules collapse upon exposure to ultrasound. Use of this phenomenon for a drug delivery system (DDS), not only for local delivery of medication but also for gene therapy, should be possible. However, enhancing the efficiency of medication is limited because capsules in suspension diffuse in the human body after injection, since the motion of capsules in blood flow cannot be controlled. To control the behavior of microcapsules, acoustic radiation force was introduced. We detected local changes in microcapsule density by producing acoustic radiation force in an artificial blood vessel. Furthermore, we theoretically estimated the conditions required for active path selection of capsules at a bifurcation point in the artificial blood vessel. We observed the difference in capsule density at both in the bifurcation point and in alternative paths downstream of the bifurcation point for different acoustic radiation forces. Comparing the experimental results with those obtained theoretically, the conditions for active path selection were calculated from the acoustic radiation force and fluid resistance of the capsules. The possibility of controlling capsule flow towards a specific point in a blood vessel was demonstrated.

  10. Short-term Influence of Drilling Fluid on Ciliates from Activated Sludge in Sequencing Batch Reactors.

    PubMed

    Babko, Roman; Kuzmina, Tatiana; Łagód, Grzegorz; Jaromin-Gleń, Katarzyna; Danko, Yaroslav; Pawłowska, Małgorzata; Pawłowski, Artur

    2017-01-01

    Spent drilling muds are the liquid residues of rock drilling operations. Due to a high concentration of suspended solids and potentially detrimental chemical properties, they can negatively affect microorganisms participating in wastewater treatment processes. We evaluated the addition of a potassium-polymer drilling fluid (DF) to activated sludge in laboratory sequencing batch reactors (SBRs) for municipal wastewater treatment. Ciliate assemblage, the most dynamic component of eukaryotes in activated sludge, and which is highly sensitive to changes in the system, was evaluated. The average ciliate abundance dropped by about 51% (SBR 2; 1% DF added) and 33% (SBR 3; 3% DF added) in comparison to the control (SBR 1; wastewater only). A decrease in the total number of ciliate species during the experiment was observed, from 25 to 24 in SBR 2 and from 17 to 13 in SBR 3. Moreover, a drop in the number of dominant (>100 individuals mL) ciliate species was observed during the experiment-from eight in the control to five in SBR 2 and four in SBR 3-signaling noticeable changes in the quantitative structure of ciliate species. The species analyzed showed different responses to DF addition. The most sensitive was , which is bacteriovorus. In contrast, two predators, and , showed no reaction to DF addition. Our results indicate that addition of potassium-polymer DF, in doses of 1 to 3% of the treated wastewater volume, had no toxic effects on ciliates, but qualitative and quantitative changes in their community were observed.

  11. Comparative study of the adsorption of acetaminophen on activated carbons in simulated gastric fluid.

    PubMed

    Rey-Mafull, Carlos A; Tacoronte, Juan E; Garcia, Raquel; Tobella, Jorge; Llópiz, Julio C; Iglesias, Alberto; Hotza, Dachamir

    2014-01-01

    Samples of commercial activated carbons (AC) obtained from different sources: Norit E Supra USP, Norit B Test EUR, and ML (Baracoa, Cuba) were investigated. The adsorption of acetaminophen, Co = 2500 mg/L, occured in simulated gastric fluid (SGF) at pH 1.2 in contact with activated carbon for 4 h at 310 K in water bath with stirring. Residual acetaminophen was monitored by UV visible. The results were converted to scale adsorption isotherms using alternative models: Langmuir TI and TII, Freundlich, Dubinin-Radushkevich (DR) and Temkin. Linearized forms of the characteristic parameters were obtained in each case. The models that best fit the experimental data were Langmuir TI and Temkin with R(2) ≥0.98. The regression best fits followed the sequence: Langmuir TI = Temkin > DR > LangmuirTII > Freundlich. The microporosity determined by adsorption of CO2 at 273 K with a single term DR regression presented R(2) > 0.98. The adsorption of acetaminophen may occur in specific sites and also in the basal region. It was determined that the adsorption process of acetaminophen on AC in SGF is spontaneous (ΔG <0) and exothermic (-ΔHads.). Moreover, the area occupied by the acetaminophen molecule was calculated with a relative error from 7.8 to 50%.

  12. TRPV4 channel is involved in the coupling of fluid viscosity changes to epithelial ciliary activity

    PubMed Central

    Andrade, Yaniré N.; Fernandes, Jacqueline; Vázquez, Esther; Fernández-Fernández, José M.; Arniges, Maite; Sánchez, Trinidad M.; Villalón, Manuel; Valverde, Miguel A.

    2005-01-01

    Autoregulation of the ciliary beat frequency (CBF) has been proposed as the mechanism used by epithelial ciliated cells to maintain the CBF and prevent the collapse of mucociliary transport under conditions of varying mucus viscosity. Despite the relevance of this regulatory response to the pathophysiology of airways and reproductive tract, the underlying cellular and molecular aspects remain unknown. Hamster oviductal ciliated cells express the transient receptor potential vanilloid 4 (TRPV4) channel, which is activated by increased viscous load involving a phospholipase A2–dependent pathway. TRPV4-transfected HeLa cells also increased their cationic currents in response to high viscous load. This mechanical activation is prevented in native ciliated cells loaded with a TRPV4 antibody. Application of the TRPV4 synthetic ligand 4α-phorbol 12,13-didecanoate increased cationic currents, intracellular Ca2+, and the CBF in the absence of a viscous load. Therefore, TRPV4 emerges as a candidate to participate in the coupling of fluid viscosity changes to the generation of the Ca2+ signal required for the autoregulation of CBF. PMID:15753126

  13. Removal of PCDD/Fs from flue gas by a fixed-bed activated carbon filter in a hazardous waste incinerator.

    PubMed

    Karademir, Aykan; Bakoglu, Mithat; Taspinar, Fatih; Ayberk, Savas

    2004-02-15

    The adsorption of polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) by activated carbon (AC) was examined in a fixed-bed AC unit in a hazardous waste incinerator (IZAYDAS) in Turkey. Results showed that the removal efficiencies of PCDD/Fs decrease as the chlorination level increases, which was explained by the difference in gas/particle partitioning of the compounds. Since dioxins are tightly adsorbed by activated carbon, other flue gas constituents showed no clear effect on the dioxin removal. Adsorption kinetics indicated that the adsorption of volatile congeners and homologues fits well with Henry's law, possibly due to the higher gaseous fractions, while the correlation was lower for lowly volatile ones. PCDD/F congeners and homologues had a concentration value up to which no adsorption occurred, which could be attributed to the insufficient contact times at the low concentrations.

  14. Theory of activated penetrant diffusion in viscous fluids and colloidal suspensions

    NASA Astrophysics Data System (ADS)

    Zhang, Rui; Schweizer, Kenneth S.

    2015-10-01

    We heuristically formulate a microscopic, force level, self-consistent nonlinear Langevin equation theory for activated barrier hopping and non-hydrodynamic diffusion of a hard sphere penetrant in very dense hard sphere fluid matrices. Penetrant dynamics is controlled by a rich competition between force relaxation due to penetrant self-motion and collective matrix structural (alpha) relaxation. In the absence of penetrant-matrix attraction, three activated dynamical regimes are predicted as a function of penetrant-matrix size ratio which are physically distinguished by penetrant jump distance and the nature of matrix motion required to facilitate its hopping. The penetrant diffusion constant decreases the fastest with size ratio for relatively small penetrants where the matrix effectively acts as a vibrating amorphous solid. Increasing penetrant-matrix attraction strength reduces penetrant diffusivity due to physical bonding. For size ratios approaching unity, a distinct dynamical regime emerges associated with strong slaving of penetrant hopping to matrix structural relaxation. A crossover regime at intermediate penetrant-matrix size ratio connects the two limiting behaviors for hard penetrants, but essentially disappears if there are strong attractions with the matrix. Activated penetrant diffusivity decreases strongly with matrix volume fraction in a manner that intensifies as the size ratio increases. We propose and implement a quasi-universal approach for activated diffusion of a rigid atomic/molecular penetrant in a supercooled liquid based on a mapping between the hard sphere system and thermal liquids. Calculations for specific systems agree reasonably well with experiments over a wide range of temperature, covering more than 10 orders of magnitude of variation of the penetrant diffusion constant.

  15. Theory of activated penetrant diffusion in viscous fluids and colloidal suspensions.

    PubMed

    Zhang, Rui; Schweizer, Kenneth S

    2015-10-14

    We heuristically formulate a microscopic, force level, self-consistent nonlinear Langevin equation theory for activated barrier hopping and non-hydrodynamic diffusion of a hard sphere penetrant in very dense hard sphere fluid matrices. Penetrant dynamics is controlled by a rich competition between force relaxation due to penetrant self-motion and collective matrix structural (alpha) relaxation. In the absence of penetrant-matrix attraction, three activated dynamical regimes are predicted as a function of penetrant-matrix size ratio which are physically distinguished by penetrant jump distance and the nature of matrix motion required to facilitate its hopping. The penetrant diffusion constant decreases the fastest with size ratio for relatively small penetrants where the matrix effectively acts as a vibrating amorphous solid. Increasing penetrant-matrix attraction strength reduces penetrant diffusivity due to physical bonding. For size ratios approaching unity, a distinct dynamical regime emerges associated with strong slaving of penetrant hopping to matrix structural relaxation. A crossover regime at intermediate penetrant-matrix size ratio connects the two limiting behaviors for hard penetrants, but essentially disappears if there are strong attractions with the matrix. Activated penetrant diffusivity decreases strongly with matrix volume fraction in a manner that intensifies as the size ratio increases. We propose and implement a quasi-universal approach for activated diffusion of a rigid atomic/molecular penetrant in a supercooled liquid based on a mapping between the hard sphere system and thermal liquids. Calculations for specific systems agree reasonably well with experiments over a wide range of temperature, covering more than 10 orders of magnitude of variation of the penetrant diffusion constant.

  16. Theory of activated penetrant diffusion in viscous fluids and colloidal suspensions

    SciTech Connect

    Zhang, Rui; Schweizer, Kenneth S.

    2015-10-14

    We heuristically formulate a microscopic, force level, self-consistent nonlinear Langevin equation theory for activated barrier hopping and non-hydrodynamic diffusion of a hard sphere penetrant in very dense hard sphere fluid matrices. Penetrant dynamics is controlled by a rich competition between force relaxation due to penetrant self-motion and collective matrix structural (alpha) relaxation. In the absence of penetrant-matrix attraction, three activated dynamical regimes are predicted as a function of penetrant-matrix size ratio which are physically distinguished by penetrant jump distance and the nature of matrix motion required to facilitate its hopping. The penetrant diffusion constant decreases the fastest with size ratio for relatively small penetrants where the matrix effectively acts as a vibrating amorphous solid. Increasing penetrant-matrix attraction strength reduces penetrant diffusivity due to physical bonding. For size ratios approaching unity, a distinct dynamical regime emerges associated with strong slaving of penetrant hopping to matrix structural relaxation. A crossover regime at intermediate penetrant-matrix size ratio connects the two limiting behaviors for hard penetrants, but essentially disappears if there are strong attractions with the matrix. Activated penetrant diffusivity decreases strongly with matrix volume fraction in a manner that intensifies as the size ratio increases. We propose and implement a quasi-universal approach for activated diffusion of a rigid atomic/molecular penetrant in a supercooled liquid based on a mapping between the hard sphere system and thermal liquids. Calculations for specific systems agree reasonably well with experiments over a wide range of temperature, covering more than 10 orders of magnitude of variation of the penetrant diffusion constant.

  17. Symmetry-breaking magnetic fields create a vortex fluid that exhibits a negative viscosity, active wetting, and strong mixing.

    PubMed

    Martin, James E; Solis, Kyle J

    2014-06-14

    There are many areas of science and technology where being able to generate vigorous, noncontact flow would be desirable. We have discovered that three dimensional, time-dependent electric or magnetic fields having key symmetries can be used to generate controlled fluid motion by the continuous injection of energy. Unlike natural convection, this approach does not require a thermal gradient as an energy source, nor does it require gravity, so space applications are feasible. The result is a highly active material we call a vortex fluid. The homogeneous torque density of this fluid enables it to climb walls, induce ballistic droplet motion, and mix vigorously, even in such complex geometries as porous media. This vortex fluid can also exhibit a negative viscosity, which can immeasurably extend the control range of the "smart fluids" used in electro- and magnetorheological devices and can thus significantly increase their performance. Because the applied fields are uniform and modest in strength, vortex fluids of any scale can be created, making applications of any size, from directing microdroplet motion to controlling damping in magnetorheological dampers that protect bridges and buildings from earthquakes, feasible.

  18. Development of a selected reaction monitoring mass spectrometry-based assay to detect asparaginyl endopeptidase activity in biological fluids

    PubMed Central

    Walker, Michael J.; Gray, Oliver J.; Parker, Catriona; Holland, Mark; Williamson, Andrew J.K.; Pierce, Andrew; Unwin, Richard D.; Krishnan, Shekhar

    2016-01-01

    Cancer Biomarkers have the capability to improve patient outcomes. They have potential applications in diagnosis, prognosis, monitoring of disease progression and measuring response to treatment. This type of information is particularly useful in the individualisation of treatment regimens. Biomarkers may take many forms but considerable effort has been made to identify and quantify proteins in biological fluids. However, a major challenge in measuring protein in biological fluids, such as plasma, is the sensitivity of the assay and the complex matrix of proteins present. Furthermore, determining the effect of proteases in disease requires measurement of their activity in biological fluids as quantification of the protein itself may not provide sufficient information. To date little progress has been made towards monitoring activity of proteases in plasma. The protease asparaginyl endopeptidase has been implicated in diseases such as breast cancer, leukaemia and dementia. Here we describe a new approach to sensitively and in a targeted fashion quantify asparaginyl endopeptidase activity in plasma using a synthetic substrate peptide protected from nonspecific hydrolysis using D-amino acids within the structure. Our selected reaction monitoring approach enabled asparaginyl endopeptidase activity to be measured in human plasma with both a high dynamic range and sensitivity. This manuscript describes a paradigm for future development of assays to measure protease activities in biological fluids as biomarkers of disease. PMID:27683124

  19. The freezing point depression of mammalian tissues in relation to the question of osmotic activity of cell fluid.

    PubMed

    APPELBOOM, J W; BRODSKY, W A; DENNIS, W H; DIAMOND, I; MILEY, J F; REHM, W S

    1956-11-20

    The freezing point depression of freshly excised frozen tissues, pulverized in a hydraulic press or in a mortar, is greater than that of plasma. Even at 0 degrees C. the freezing point depression of such homogenates increases significantly with time. Dilution data indicate that such freezing point data are valid. The presence of intact cells has been shown in smears of tissues pulverized in a mortar, but not in smears of those crushed in a hydraulic press. The osmolarity of various diluent solutions affects the calculated osmotic activity of tissue homogenates presumably because of delayed diffusion between the diluent and cell fluid. With a hypertonic NaCl diluent, spuriously low values of tissue osmotic activity are found from calculations assuming instantaneous mixing between homogenates and diluents. The limitations of data from cryoscopic experiments and from tissue-swelling experiments are discussed in relation to the basic question of whether or not cell fluid is isotonic to extracellular fluid.

  20. 7 CFR 2902.15 - Bedding, bed linens, and towels.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Bedding, bed linens, and towels. 2902.15 Section 2902... PROCUREMENT Designated Items § 2902.15 Bedding, bed linens, and towels. (a) Definition. (1) Bedding is that..., bedspreads, comforters, and quilts. (2) Bed linens are woven cloth sheets and pillowcases used in bedding....

  1. 7 CFR 3201.15 - Bedding, bed linens, and towels.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Bedding, bed linens, and towels. 3201.15 Section 3201... PROCUREMENT Designated Items § 3201.15 Bedding, bed linens, and towels. (a) Definition. (1) Bedding is that..., bedspreads, comforters, and quilts. (2) Bed linens are woven cloth sheets and pillowcases used in bedding....

  2. 7 CFR 3201.15 - Bedding, bed linens, and towels.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Bedding, bed linens, and towels. 3201.15 Section 3201... PROCUREMENT Designated Items § 3201.15 Bedding, bed linens, and towels. (a) Definition. (1) Bedding is that..., bedspreads, comforters, and quilts. (2) Bed linens are woven cloth sheets and pillowcases used in bedding....

  3. 7 CFR 2902.15 - Bedding, bed linens, and towels.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Bedding, bed linens, and towels. 2902.15 Section 2902... PROCUREMENT Designated Items § 2902.15 Bedding, bed linens, and towels. (a) Definition. (1) Bedding is that..., bedspreads, comforters, and quilts. (2) Bed linens are woven cloth sheets and pillowcases used in bedding....

  4. 7 CFR 3201.15 - Bedding, bed linens, and towels.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Bedding, bed linens, and towels. 3201.15 Section 3201... PROCUREMENT Designated Items § 3201.15 Bedding, bed linens, and towels. (a) Definition. (1) Bedding is that..., bedspreads, comforters, and quilts. (2) Bed linens are woven cloth sheets and pillowcases used in bedding....

  5. Simulating the performance of fixed-bed granular activated carbon adsorbers: removal of synthetic organic chemicals in the presence of background organic matter.

    PubMed

    Jarvie, Michelle Edith; Hand, David W; Bhuvendralingam, Shanmugalingam; Crittenden, John C; Hokanson, Dave R

    2005-06-01

    Granular activated carbon (GAC) adsorption is an effective treatment technology for the removal of synthetic organic chemicals (SOCs) from drinking water supplies. This treatment process can be expensive if not properly designed. Application of mathematical models is an attractive method to evaluate the impact of process variables on process design and performance. Practical guidelines were developed to select an appropriate model framework and to estimate site-specific model parameters to predict GAC adsorber performance. Pilot plant and field-scale data from 11 different studies were utilized to investigate the effectiveness of this approach in predicting adsorber performance in the presence of background organic batter (BOM). These data represent surface and ground water sources from four different countries. The modeling approach was able to adequately describe fixed-bed adsorber performance for the purpose of determining the carbon usage rate and process design variables. This approach is more accurate at predicting bed life in the presence of BOM than the current methods commonly used by practicing engineers.

  6. Lifting a large object from an anisotropic porous bed

    NASA Astrophysics Data System (ADS)

    Karmakar, Timir; Raja Sekhar, G. P.

    2016-09-01

    An analytical study of two dimensional problem of lifting an object from the top of a fully saturated rigid porous bed is discussed. It is assumed that the porous bed is anisotropic in nature. The flow within the gap region between the object and the porous bed is assumed to be governed by Stokes equation while the flow within the porous bed is governed by Brinkman equation. The breakout phenomenon for different kinds of soil is reported. The effect of mechanical properties like anisotropic permeability, grain diameter size, and porosity on streamlines, velocity, and force is analyzed. Relevant comparison with C. C. Mei, R. W. Yeung, and K. F. Liu ["Lifting a large object from a porous bed," J. Fluid. Mech. 152, 203-215 (1985)] and Y. Chang, L. H. Huang and F. P. Y. Yang ["Two-dimensional lift-up problem for a rigid porous bed," Phys. Fluids, 27, 053101 (2015)] is done.

  7. Migrating Activity of the 2010 Madison Plateau, Yellowstone National Park, Earthquake Swarm: Evidence for Fluid Triggering?

    NASA Astrophysics Data System (ADS)

    Shelly, D. R.; Hill, D. P.; Farrell, J.; Massin, F.; Smith, R. B.

    2012-12-01

    activity may have been triggered by the rupture of a confined high-pressure fluid system into neighboring pre-existing crustal fractures. Besides the outward expansion of hypocenters in a manner consistent with diffusional fluid flow, we observe that the swarm activity front is usually led by small earthquakes rather than large ones. The front sometimes propagates outwardly in linear "finger-like" structures consistent with pressure increases along highly permeable linear pathways. Interestingly, nodal planes from double-couple-constrained fault solutions are dominantly strike-slip and are oblique to the general trend of hypocenters. This may suggest en-echelon faulting and/or a component of fault opening, perhaps in a fracture mesh geometry similar to that envisioned by Hill [1977]. The primary dipping structure is likely an inherited Basin and Range normal fault, which could provide a permeable pathway of this orientation. This swarm exhibits many similarities with the 1985 Yellowstone swarm just 5 km to the NW, including its migration patterns and dominant orientation (roughly perpendicular to both the minimum regional compressive stress and the caldera boundary). It is also only ~20 km SE from the closest rupture of the deadly M 7.3 1959 Hebgen Lake normal-faulting earthquake.

  8. Hybrid fluidized bed combuster

    DOEpatents

    Kantesaria, Prabhudas P.; Matthews, Francis T.

    1982-01-01

    A first atmospheric bubbling fluidized bed furnace is combined with a second turbulent, circulating fluidized bed furnace to produce heat efficiently from crushed solid fuel. The bed of the second furnace receives the smaller sizes of crushed solid fuel, unreacted limestone from the first bed, and elutriated solids extracted from the flu gases of the first bed. The two-stage combustion of crushed solid fuel provides a system with an efficiency greater than available with use of a single furnace of a fluidized bed.

  9. March 2016 Memo: Planning for Removal and Remedial Activities at Hardrock Mining and Mineral Processing Sites with Fluid Hazards

    EPA Pesticide Factsheets

    Memo from EPA Assistant Administrator Mathy Stanislaus, regarding planning for removal and remedial activities at hardrock mining and mineral processing sites with fluid hazards, and to share the Agency’s expectations for the work that is done at these sit

  10. Apparatus for irradiating a continuously flowing stream of fluid. [For neutron activation analysis

    DOEpatents

    Speir, L.G.; Adams, E.L.

    1982-05-13

    An apparatus for irradiating a continuously flowing stream of fluid is disclosed. The apparatus consists of a housing having a spherical cavity and a spherical moderator containing a radiation source positioned within the spherical cavity. The spherical moderator is of lesser diameter than the spherical cavity so as to define a spherical annular volume around the moderator. The housing includes fluid intake and output conduits which open onto the spherical cavity at diametrically opposite positions. Fluid flows through the cavity around the spherical moderator and is uniformly irradiated due to the 4..pi.. radiation geometry. The irradiation source, for example a /sup 252/Cf neutron source, is removable from the spherical moderator through a radial bore which extends outwardly to an opening on the outside of the housing. The radiation source may be routinely removed without interrupting the flow of fluid or breaching the containment of the fluid.

  11. Bed material agglomeration during fluidized bed combustion

    SciTech Connect

    Brown, R.C.; Dawson, M.R.; Noble, S.

    1993-02-01

    The purpose of this project is to determine the physical and chemical reactions which led to the undesired agglomeration of bed material during fluidized bed combustion and to relate these reactions to specific causes. Survey of industrial-scale fluidized bed combustors is being conducted to determine the occurrence of bed agglomeration and the circumstances under which agglomeration took place. This task should be finished by the end of February. Samples of bed material, agglomerate material, and boiler deposits are being requested from boiler operators as part of the survey. Once received, these sample will be analyzed to determine chemical and mineralogic composition. The bulk chemical determination will be performed using x-ray fluorescence and inductively coupled plasma-optical emission (ICP). Mineralogy will be detected by x-ray diffraction (XRD). Chemical and mineral reactions will be determined by scanning electron microscopy, optical microscopy, and electron microprobe.

  12. Composition and antioxidant activity of Thymus vulgaris volatiles: comparison between supercritical fluid extraction and hydrodistillation.

    PubMed

    Grosso, Clara; Figueiredo, Ana Cristina; Burillo, Jesus; Mainar, Ana M; Urieta, José S; Barroso, José G; Coelho, José A; Palavra, António M F

    2010-07-01

    Supercritical fluid extraction (SFE) of the volatile oil from Thymus vulgaris L. aerial flowering parts was performed under different conditions of pressure, temperature, mean particle size and CO(2) flow rate and the correspondent yield and composition were compared with those of the essential oil isolated by hydrodistillation (HD). Both the oils were analyzed by GC and GC-MS and 52 components were identified. The main volatile components obtained were p-cymene (10.0-42.6% for SFE and 28.9-34.8% for HD), gamma-terpinene (0.8-6.9% for SFE and 5.1-7.0% for HD), linalool (2.3-5.3% for SFE and 2.8-3.1% for HD), thymol (19.5-40.8% for SFE and 35.4-41.6% for HD), and carvacrol (1.4-3.1% for SFE and 2.6-3.1% for HD). The main difference was found to be the relative percentage of thymoquinone (not found in the essential oil) and carvacryl methyl ether (1.0-1.2% for HD versus t-0.4 for SFE) which can explain the higher antioxidant activity, assessed by Rancimat test, of the SFE volatiles when compared with HD. Thymoquinone is considered a strong antioxidant compound.

  13. Human Cerebrospinal Fluid Promotes Neuronal Viability and Activity of Hippocampal Neuronal Circuits In Vitro

    PubMed Central

    Perez-Alcazar, Marta; Culley, Georgia; Lyckenvik, Tim; Mobarrez, Kristoffer; Bjorefeldt, Andreas; Wasling, Pontus; Seth, Henrik; Asztely, Frederik; Harrer, Andrea; Iglseder, Bernhard; Aigner, Ludwig; Hanse, Eric; Illes, Sebastian

    2016-01-01

    For decades it has been hypothesized that molecules within the cerebrospinal fluid (CSF) diffuse into the brain parenchyma and influence the function of neurons. However, the functional consequences of CSF on neuronal circuits are largely unexplored and unknown. A major reason for this is the absence of appropriate neuronal in vitro model systems, and it is uncertain if neurons cultured in pure CSF survive and preserve electrophysiological functionality in vitro. In this article, we present an approach to address how human CSF (hCSF) influences neuronal circuits in vitro. We validate our approach by comparing the morphology, viability, and electrophysiological function of single neurons and at the network level in rat organotypic slice and primary neuronal cultures cultivated either in hCSF or in defined standard culture media. Our results demonstrate that rodent hippocampal slices and primary neurons cultured in hCSF maintain neuronal morphology and preserve synaptic transmission. Importantly, we show that hCSF increases neuronal viability and the number of electrophysiologically active neurons in comparison to the culture media. In summary, our data indicate that hCSF represents a physiological environment for neurons in vitro and a superior culture condition compared to the defined standard media. Moreover, this experimental approach paves the way to assess the functional consequences of CSF on neuronal circuits as well as suggesting a novel strategy for central nervous system (CNS) disease modeling. PMID:26973467

  14. Changes in Purines Concentration in the Cerebrospinal Fluid of Pregnant Women Experiencing Pain During Active Labor.

    PubMed

    Schmidt, André P; Böhmer, Ana E; Hansel, Gisele; Soares, Félix A; Oses, Jean P; Giordani, Alex T; Posso, Irimar P; Auler, José Otávio C; Mendes, Florentino F; Félix, Elaine A; Portela, Luís V; Souza, Diogo O

    2015-11-01

    Labor pain has been reported as a severe pain and can be considered as a model of acute visceral pain. It is well known that extracellular purines have an important role in pain signaling in the central nervous system. This study analyzes the relationship between extracellular purines and pain perception during active labor. A prospective observational study was performed. Cerebrospinal fluid (CSF) levels of the purines and their metabolites were compared between women at term pregnancy with labor pain (n = 49) and without labor pain (Caesarian section; n = 47). Control groups (healthy men and women without chronic or acute pain-n = 40 and 32, respectively) were also investigated. The CSF levels of adenosine were significantly lower in the labor pain group (P = 0.026) and negatively correlated with pain intensity measured by a visual analogue scale (r = -0.48, P = 0.0005). Interestingly, CSF levels of uric acid were significantly higher in healthy men as compared to women. Additionally, pregnant women showed increased CSF levels of ADP, GDP, adenosine and guanosine and reduced CSF levels of AMP, GTP, and uric acid as compared to non-pregnant women (P < 0.05). These findings suggest that purines, in special the nucleoside adenosine, are associated with pregnancy and labor pain.

  15. How yawning switches the default-mode network to the attentional network by activating the cerebrospinal fluid flow.

    PubMed

    Walusinski, Olivier

    2014-03-01

    Yawning is a behavior to which little research has been devoted. However, its purpose has not yet been demonstrated and remains controversial. In this article, we propose a new theory involving the brain network that is functional during the resting state, that is, the default mode network. When this network is active, yawning manifests a process of switching to the attentional system through its capacity to increase circulation of cerebrospinal fluid (CSF), thereby increasing clearance of somnogenic factors (prostaglandin D(2), adenosine, and others) accumulating in the cerebrospinal fluid.

  16. Effects Of Exercise During Prolonged Bed Rest

    NASA Technical Reports Server (NTRS)

    Arnaud, S.; Berry, P; Cohen, M.; Danelis, J.; Deroshia, C.; Greenleaf, J.; Harris, B.; Keil, L.; Bernauer, E.; Bond, M.; Ellis, S.; Lee, P.; Selzer, R.; Wade, C.

    1992-01-01

    Report describes experiment to investigate effects of isotonic and isokinetic leg exercises in counteracting effects of bed rest upon physical and mental conditions of subjects. Data taken on capacity for work, endurance and strength, tolerance to sitting up, equilibrium, posture, gait, atrophy, mineralization and density of bones, endocrine analyses concerning vasoactivity and fluid and electrolyte balances, intermediary metabolism of muscles, mood, and performance.

  17. Improved lignin pyrolysis for phenolics production in a bubbling bed reactor--Effect of bed materials.

    PubMed

    Li, Dongbing; Briens, Cedric; Berruti, Franco

    2015-01-01

    Lignin pyrolysis was studied in a bubbling fluidized bed reactor equipped with a fractional condensation train, using nitrogen as the fluidization gas. The effect of different bed materials (silica sand, lignin char, activated lignin char, birch bark char, and foamed glass beads) on bio-oil yield and quality was investigated for a pyrolysis temperature of 550 °C. Results how that a bed of activated lignin char is preferable to the commonly used silica sand: pyrolysis of Kraft lignin with a bed of activated lignin char not only provides a pure char product, but also a higher dry bio-oil yield (with a relative increase of 43%), lower pyrolytic water production, and better bio-oil quality. The bio-oil obtained from Kraft lignin pyrolysis with a bed of activated lignin char has a lower average molecular weight, less tar, more phenolics, and less acidity than when sand is used as bed material.

  18. Bed Bugs and Schools

    EPA Pesticide Factsheets

    Bed bugs have long been a pest – feeding on blood, causing itchy bites and generally irritating their human hosts. They are successful hitchhikers, and can move from an infested site to furniture, bedding, baggage, boxes, and clothing.

  19. Bed rest during pregnancy

    MedlinePlus

    ... on the inferior vena cava. How Can I Deal with Discomfort from Bed Rest? Bed rest can ... Group Health Cooperative, Bellevue, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the ...

  20. Correlations of Ventricular Enlargement with Rheologically Active Surfactant Proteins in Cerebrospinal Fluid

    PubMed Central

    Schob, Stefan; Weiß, Alexander; Dieckow, Julia; Richter, Cindy; Pirlich, Mandy; Voigt, Peter; Surov, Alexey; Hoffmann, Karl-Titus; Quaeschling, Ulf; Preuß, Matthias

    2017-01-01

    Purpose: Surfactant proteins (SPs) are involved in the regulation of rheological properties of body fluids. Concentrations of SPs are altered in the cerebrospinal fluid (CSF) of hydrocephalus patients. The common hallmark of hydrocephalus is enlargement of the brain ventricles. The relationship of both phenomena has not yet been investigated. The aim of this study was to evaluate the association between SP concentrations in the CSF and enlargement of the brain ventricles. Procedures: Ninty-six individuals (41 healthy subjects and 55 hydrocephalus patients) were included in this retrospective analysis. CSF specimens were analyzed for SP-A, SP-B, SP-C and SP-D concentrations by use of enzyme linked immunosorbent assays (ELISA). Ventricular enlargement was quantified in T2 weighted (T2w) magnetic resonance imaging (MRI) sections using an uni-dimensional (Evans’ Index) and a two-dimensional approach (lateral ventricles area index, LVAI). Results: CSF-SP concentrations (mean ± standard deviation in ng/ml) were as follows: SP-A 0.71 ± 0.58, SP-B 0.18 ± 0.43, SP-C 0.89 ± 0.77 and SP-D 7.4 ± 5.4. Calculated values of Evans’ Index were 0.37 ± 0.11, a calculation of LVAI resulted in 0.18 ± 0.15 (each mean ± standard deviation). Significant correlations were identified for Evans’ Index with SP-A (r = 0.388, p < 0.001) and SP-C (r = 0.392, p < 0.001), LVAI with SP-A (r = 0.352, p = 0.001), SP-C (r = 0.471, p < 0.001) and SP-D (r = 0.233, p = 0.025). Furthermore, SP-C showed a clear inverse correlation with age (r = −0.357, p = 0.011). Conclusion: The present study confirmed significant correlations between SPs A, C and D in the CSF with enlargement of the inner CSF spaces. In conclusion, SPs clearly play an important role for CSF rheology. CSF rheology is profoundly altered in hydrocephalic diseases, however, diagnosis and therapy of hydrocephalic conditions are still almost exclusively based on ventricular enlargement. Until now it was unclear, whether the

  1. Pretreatment of lignocellulosic biomass by cattle rumen fluid for methane production: Bacterial flora and enzyme activity analysis.

    PubMed

    Baba, Yasunori; Matsuki, Yu; Mori, Yumi; Suyama, Yoshihisa; Tada, Chika; Fukuda, Yasuhiro; Saito, Masanori; Nakai, Yutaka

    2017-01-29

    We attempted to develop a pretreatment method for methane fermentation of lignocellulosic biomass using cattle rumen fluid, treated as slaughterhouse waste. When rapeseed (Brassica napus L.) was added to the methane fermentation after being solubilized with rumen fluid, 1.5 times more methane was produced compared with untreated rapeseed. Analysis of the bacterial flora during rumen fluid treatment using the MiSeq next-generation sequencer showed that the predominant phylum shifted from Bacteroidetes, composed of amylolytic Prevotella spp., to Firmicutes, composed of cellulolytic and xylanolytic Ruminococcus spp., in only 6 h. In total, 7 cellulolytic, 25 cello-oligosaccharolytic, and 11 xylanolytic bacteria were detected after investigating the most abundant sequences of detected taxa. The relative abundance of two Ruminococcus species (Ruminococcus albus and R. flavefaciens), known as cellulolytic, cello-oligosaccharolytic, and xylanolytic bacteria, increased with increasing cellulose and hemicellulose degradation rates, and, finally, comprised 48% of all operational taxonomic units. The chronological observation of enzyme activities showed that cellulolytic and xylanolytic activities increased 6 h later, and that oligosaccharolytic activity increased 24 h later. This study detected six bacteria that participate in the degradation of aromatics derived from lignin, which have rarely been reported in rumen fluid. The constitution of the detected bacteria suggests that the aromatics were converted into acetate via benzoate. The list of microbes that cover all lignocellulose-degrading candidates will provide fundamental knowledge for future studies focusing on rumen microbes.

  2. Fluid shear promotes chondrosarcoma cell invasion by activating matrix metalloproteinase 12 via IGF-2 and VEGF signaling pathways

    PubMed Central

    Wang, P; Chen, S-H; Hung, W-C; Paul, C; Zhu, F; Guan, P-P; Huso, DL; Kontrogianni-Konstantopoulos, A; Konstantopoulos, K

    2015-01-01

    Interstitial fluid flow in and around the tumor tissue is a physiologically relevant mechanical signal that regulates intracellular signaling pathways throughout the tumor. Yet, the effects of interstitial flow and associated fluid shear stress on the tumor cell function have been largely overlooked. Using in vitro bioengineering models in conjunction with molecular cell biology tools, we found that fluid shear (2 dyn/cm2) markedly upregulates matrix metalloproteinase 12 (MMP-12) expression and its activity in human chondrosarcoma cells. MMP-12 expression is induced in human chondrocytes during malignant transformation. However, the signaling pathway regulating MMP-12 expression and its potential role in human chondrosarcoma cell invasion and metastasis have yet to be delineated. We discovered that fluid shear stress induces the synthesis of insulin growth factor-2 (IGF-2) and vascular endothelial growth factor (VEGF) B and D, which in turn transactivate MMP-12 via PI3-K, p38 and JNK signaling pathways. IGF-2-, VEGF-B- or VEGF-D-stimulated chondrosarcoma cells display markedly higher migratory and invasive potentials in vitro, which are blocked by inhibiting MMP-12, PI3-K, p38 or JNK activity. Moreover, recombinant human MMP-12 or MMP-12 overexpression can potentiate chondrosarcoma cell invasion in vitro and the lung colonization in vivo. By reconstructing and delineating the signaling pathway regulating MMP-12 activation, potential therapeutic strategies that interfere with chondrosarcoma cell invasion may be identified. PMID:25435370

  3. Glutathione S-transferase activity in follicular fluid from women undergoing ovarian stimulation: role in maturation.

    PubMed

    Meijide, Susana; Hernández, M Luisa; Navarro, Rosaura; Larreategui, Zaloa; Ferrando, Marcos; Ruiz-Sanz, José Ignacio; Ruiz-Larrea, M Begoña

    2014-10-01

    Female infertility involves an emotional impact for the woman, often leading to a state of anxiety and low self-esteem. The assisted reproduction techniques (ART) are used to overcome the problem of infertility. In a first step of the in vitro fertilization therapy women are subjected to an ovarian stimulation protocol to obtain mature oocytes, which will result in competent oocytes necessary for fertilization to occur. Ovarian stimulation, however, subjects the women to a high physical and psychological stress, thus being essential to improve ART and to find biomarkers of dysfunction and fertility. GSH is an important antioxidant, and is also used in detoxification reactions, catalysed by glutathione S-transferases (GST). In the present work, we have investigated the involvement of GST in follicular maturation. Patients with fertility problems and oocyte donors were recruited for the study. From each woman follicles at two stages of maturation were extracted at the preovulatory stage. Follicular fluid was separated from the oocyte by centrifugation and used as the enzyme source. GST activity was determined based on its conjugation with 3,4-dichloronitrobenzene and the assay was adapted to a 96-well microplate reader. The absorbance was represented against the incubation time and the curves were adjusted to linearity (R(2)>0.990). Results showed that in both donors and patients GST activity was significantly lower in mature oocytes compared to small ones. These results suggest that GST may play a role in the follicle maturation by detoxifying xenobiotics, thus contributing to the normal development of the oocyte. Supported by FIS/FEDER (PI11/02559), Gobierno Vasco (Dep. Educación, Universiades e Investigación, IT687-13), and UPV/EHU (CLUMBER UFI11/20 and PES13/58). The work was approved by the Ethics Committee of the UPV/EHU (CEISH/96/2011/RUIZLARREA), and performed according to the UPV/EHU and IVI-Bilbao agreement (Ref. 2012/01).

  4. Effects of loading concentration, blood and synovial fluid on antibiotic release and anti-biofilm activity of bone cement beads.

    PubMed

    Dusane, Devendra H; Diamond, Scott M; Knecht, Cory S; Farrar, Nicholas R; Peters, Casey W; Howlin, Robert P; Swearingen, Matthew C; Calhoun, Jason H; Plaut, Roger D; Nocera, Tanya M; Granger, Jeffrey F; Stoodley, Paul

    2017-02-28

    Antibiotic loaded cement beads are commonly used for the treatment of biofilm related orthopaedic periprosthetic infections; however the effects of antibiotic loading and exposure of beads to body fluids on release kinetics are unclear. The purpose of this study was to determine the effects of (i) antibiotic loading density (ii) loading amount (iii) material type and (iv) exposure to body fluids (blood or synovial fluid) on release kinetics and efficacy of antibiotics against planktonic and lawn biofilm bacteria. Short-term release into an agar gel was evaluated using a fluorescent tracer (fluorescein) incorporated in the carrier materials calcium sulfate (CaSO4) and poly methyl methacrylate (PMMA). Different fluorescein concentrations in CaSO4 beads were evaluated. Mechanical properties of fluorescein-incorporated beads were analyzed. Efficacy of the antibiotics vancomycin (VAN) or tobramycin (TOB) alone and in combination was evaluated against lawn biofilms of bioluminescent strains of Staphylococcus aureus and Pseudomonas aeruginosa. Zones of inhibition of cultures (ZOI) were measured visually and using an in-vivo imaging system (IVIS). The influence of body fluids on release was assessed using CaSO4 beads that contained fluorescein or antibiotics and were pre-coated with human blood or synovial fluid. The spread from the beads followed a square root of time relationship in all cases. The loading concentration had no influence on short-term fluorescein release and pre-coating of beads with body fluids did not affect short-term release or antibacterial activity. Compared to PMMA, CaSO4 had a more rapid short term rate of elution and activity against planktonic and lawn biofilms. This study highlights the importance of considering antibiotic loading and packing density when investigating the clinical application of bone cements for infection management.

  5. Method and equipment for treatment of fuel for fluidized bed combustion

    SciTech Connect

    Beranek, J.; Cermak, J.; Dobrozemsky, J.; Fibinger, V.

    1982-04-20

    The invention relates to the method and equipment for treatment of fuel for fluidized bed combustion, which includes drying, classification and crushing of the fuel. The method for treatment of fuel comprises mixing the fuel with hot ash removed from the fluidized bed combustor and drying said mixture in a fluidized bed dryer in which the velocity of the fluidization fluid equals or is lower than the minimum fluidization velocity of particles in the fluidized bed combustor. The equipment for treatment of fuel comprises a bunker, crusher and dryer, comprising a fluidized bed dryer provided with appropriate piping for interconnection of the fluidized bed dryer, fluidized bed combuster, fuel bunker and crusher.

  6. Method and equipment for treatment of fuel for fluidized bed combustion

    SciTech Connect

    Beranek, J.; Dobrozemsky, J.; Fibinger, V.; Germak, J.

    1983-11-15

    The invention relates to the method and equipment for treatment of fuel for fluidized bed combustion, which includes drying, classification and crushing of the fuel. The method for treatment of fuel comprises mixing the fuel with hot ash removed from the fluidized bed combustor and drying said mixture in a fluidized bed dryer in which the velocity of the fluidization fluid equals or is lower than the minimum fluidization velocity of particles in the fluidized bed combustor. The equipment for treatment of fuel comprises a bunker, crusher and dryer, comprising a fluidized bed dryer provided with appropriate piping for interconnection of the fluidized bed dryer, fluidized bed combustor, fuel bunker and crusher.

  7. Introduction to Bed Bugs

    EPA Pesticide Factsheets

    The common bed bug (Cimex lectularius) is a pest – feeding on blood, causing itchy bites and generally irritating their human hosts. EPA and other agencies all consider bed bugs a public health pest, but bed bugs are not known to transmit disease.

  8. Making a Bed

    ERIC Educational Resources Information Center

    Wexler, Anthony; Stein, Sherman

    2005-01-01

    The origins of this paper lay in making beds by putting pieces of plywood on a frame: If beds need to be 4 feet 6 inches by 6 feet 3 inches, and plywood comes in 4-foot by 8-foot sheets, how should one cut the plywood to minimize waste (and have stable beds)? The problem is of course generalized.

  9. Three-dimensional structure of fluid conduits sustaining an active deep marine cold seep

    USGS Publications Warehouse

    Hornbach, M.J.; Ruppel, C.; Van Dover, C.L.

    2007-01-01

    Cold seeps in deep marine settings emit fluids to the overlying ocean and are often associated with such seafloor flux indicators as chemosynthetic biota, pockmarks, and authigenic carbonate rocks. Despite evidence for spatiotemporal variability in the rate, locus, and composition of cold seep fluid emissions, the shallow subseafloor plumbing systems have never been clearly imaged in three dimensions. Using a novel, high-resolution approach, we produce the first three-dimensional image of possible fluid conduits beneath a cold seep at a study site within the Blake Ridge gas hydrate province. Complex, dendritic features diverge upward toward the seafloor from feeder conduits at depth and could potentially draw flow laterally by up to 103 m from the known seafloor seep, a pattern similar to that suggested for some hydrothermal vents. The biodiversity, community structure, and succession dynamics of chemosynthetic communities at cold seeps may largely reflect these complexities of subseafloor fluid flow.

  10. Cerebroside Sulfatase Activity in Cultivated Human Skin Fibroblasts and Amniotic Fluid Cells

    ERIC Educational Resources Information Center

    Booth, Carol W.; And Others

    1975-01-01

    Prenatal monitoring for metachromatic leukodystrophy (a fatal inherited metabolic disorder) suggested that the determination of levels of cerebroside sulfatase in the amniotic fluid helped in the prenatal detection of this disorder. (DB)

  11. Fluidized bed combustor and tube construction therefor

    DOEpatents

    De Feo, Angelo; Hosek, William

    1981-01-01

    A fluidized bed combustor comprises a reactor or a housing which has a windbox distributor plate adjacent the lower end thereof which contains a multiplicity of hole and air discharge nozzles for discharging air and coal into a fluidized bed which is maintained above the distributor plate and below a take-off connection or flue to a cyclone separator in which some of the products of combustion are treated to remove the dust which is returned into the fluidized bed. A windbox is spaced below the fluidized bed and it has a plurality of tubes passing therethrough with the passage of combustion air and fluidizing air which passes through an air space so that fluidizing air is discharged into the reaction chamber fluidized bed at the bottom thereof to maintain the bed in a fluidized condition. A fluid, such as air, is passed through the tubes which extend through the windbox and provide a preheating of the combustion air and into an annular space between telescoped inner and outer tubes which comprise heat exchanger tubes or cooling tubes which extend upwardly through the distributor plate into the fluidized bed. The heat exchanger tubes are advantageously arranged so that they may be exposed in groups within the reactor in a cluster which is arranged within holding rings.

  12. Tube construction for fluidized bed combustor

    DOEpatents

    De Feo, Angelo; Hosek, William

    1984-01-01

    A fluidized bed combustor comprises a reactor or a housing which has a windbox distributor plate adjacent the lower end thereof which contains a multiplicity of hole and air discharge nozzles for discharging air and coal into a fluidized bed which is maintained above the distributor plate and below a take-off connection or flue to a cyclone separator in which some of the products of combustion are treated to remove the dust which is returned into the fluidized bed. A windbox is spaced below the fluidized bed and it has a plurality of tubes passing therethrough with the passage of combustion air and fluidizing air which passes through an air space so that fluidizing air is discharged into the reaction chamber fluidized bed at the bottom thereof to maintain the bed in a fluidized condition. A fluid, such as air, is passed through the tubes which extend through the windbox and provide a preheating of the combustion air and into an annular space between telescoped inner and outer tubes which comprise heat exchanger tubes or cooling tubes which extend upwardly through the distributor plate into the fluidized bed. The heat exchanger tubes are advantageously arranged so that they may be exposed in groups within the reactor in a cluster which is arranged within holding rings.

  13. Bone marrow fat accumulation after 60 days of bed rest persisted 1 year after activities were resumed along with hemopoietic stimulation: the Women International Space Simulation for Exploration study.

    PubMed

    Trudel, Guy; Payne, Michael; Mädler, Burkhard; Ramachandran, Nanthan; Lecompte, Martin; Wade, Charles; Biolo, Gianni; Blanc, Stéphane; Hughson, Richard; Bear, Lisa; Uhthoff, Hans K

    2009-08-01

    Immobility in bed and decreased mobility cause adaptations to most human body systems. The effect of immobility on fat accumulation in hemopoietic bone marrow has never been measured prospectively. The reversibility of marrow fat accumulation and the effects on hemopoiesis are not known. In the present study, 24 healthy women (age: 25-40 yr) underwent -6 degrees head-down bed rest for 60 days. We used MRI to noninvasively measure the lumbar vertebral fat fraction at various time points. We also measured hemoglobin, erythropoietin, reticulocytes, leukocytes, platelet count, peripheral fat mass, leptin, cortisol, and C-reactive protein during bed rest and for 1 yr after bed rest ended. Compared with baseline, the mean (+/-SE) fat fraction was increased after 60 days of bed rest (+2.5+/-1.1%, P<0.05); the increase persisted 1 yr after the resumption of regular activities (+2.3+/-0.8%, P<0.05). Mean hemoglobin levels were significantly decreased 6 days after bed rest ended (-1.36+/-0.20 g/dl, P<0.05) but had recovered at 1 yr, with significantly lower mean circulating erythropoietin levels (-3.8+/-1.2 mU/ml, P<0.05). Mean numbers of neutrophils and lymphocytes remained significantly elevated at 1 yr (+617+/-218 neutrophils/microl and +498+/-112 lymphocytes/microl, both P<0.05). These results constitute direct evidence that bed rest irreversibly accelerated fat accumulation in hemopoietic bone marrow. The 2.5% increase in fat fraction after 60 days of bed rest was 25-fold larger than expected from historical ambulatory controls. Sixty days of bed rest accelerated by 4 yr the normal bone marrow involution. Bed rest and marrow adiposity were associated with hemopoietic stimulation. One year after subjects returned to normal activities, hemoglobin levels were maintained, with 43% lower circulating erythropoietin levels, and leukocytes remained significantly elevated across lineages. Lack of mobility alters hemopoiesis, possibly through marrow fat accumulation, with

  14. Sulfide-oxidizing activity and bacterial community structure in a fluidized bed reactor from a zero-discharge mariculture system.

    PubMed

    Cytryn, Eddie; Minz, Dror; Gelfand, Ilya; Neori, Amir; Gieseke, Armin; De Beer, Dirk; Van Rijn, Jaap

    2005-03-15

    In the present work we describe a comprehensive analysis of sulfide oxidation in a fluidized bed reactor (FBR) from an environmentally sustainable, zero-discharge mariculture system. The FBR received oxygen-depleted effluent from a digestion basin (DB) that is responsible for gasification of organic matter and nitrogen. The FBR is a crucial component in this recirculating system because it safeguards the fish from the toxic sulfide produced in the DB. Microscale sulfide oxidation potential and bacterial community composition within FBR biofilms were correlated to biofilter performance by integrating bulk chemical, microsensor (O2, pH, and H2S), and molecular microbial community analyses. The FBR consistently oxidized sulfide during two years of continuous operation, with an estimated average sulfide removal rate of 1.3 g of sulfide-S L(FBR)(-1) d(-1). Maximum sulfide oxidation rates within the FBR biofilms were 0.36 and 0.21 mg of sulfide-S cm(-3) h(-1) in the oxic and anoxic layers, respectively, indicating that both oxygen and nitrate serve as electron acceptors for sulfide oxidation. The estimated anoxic sulfide removal rate, as extrapolated from bench scale, autotrophic, nitrate-amended experiments, was 0.7 g of sulfide-S L(FBR)(-1) d(-1), which is approximately 50% of the total estimated sulfide removal in the FBR. Community composition analyses using denaturing gradient gel electrophoresis (DGGE) of bacterial 16S rRNA gene fragments from FBR samples taken at six-month intervals revealed several sequences that were closely affiliated with sulfide-oxidizing bacteria. These included the denitrifying, sulfide-oxidizing bacteria Thiomicrospira denitrificans, members of the filamentous Thiothrix genus, and sulfide-oxidizing symbionts from the Gammaproteobacteria. In addition, marine Alphaproteobacteria and Bacteroidetes species were present in all of the DGGE profiles examined. DGGE analyses showed significant shifts in the bacterial community composition between

  15. Modeling energy transport in a cantilevered Euler-Bernoulli beam actively vibrating in Newtonian fluid

    NASA Astrophysics Data System (ADS)

    Faria, Cassio T.; Inman, Daniel J.

    2014-04-01

    When a mechanical and/or structural component is immersed in a fluid and it vibrates, the reasonable assumption is that part of the energy is transmitted to the adjacent media. For some engineering applications the energy transport between these two domains, i.e., structure and fluid, plays a central role. The work presented in this paper is focused on discussing the energy transport in beam-like structures as they can be used to represent flexible swimmers (fish-like pulsating mechanisms) in their simplest form. In order to expose the role of each of the fluid and beam properties effecting the energy transfer process, a simplified analytical fluid-structure interaction (FSI) model is derived. After analysis of the resulting coupled-systems' damping coefficient, a new energy transport component is added to the initial Euler-Bernoulli beam equation; a term associated with diffusion (fluid viscosity). In addition our modeling results in an added mass term, a characteristic consistent with previous literature. While deriving the model, an important assumption is made: beam mode shapes are not significantly affected by the domains' interaction. This hypothesis is experimentally tested in two different fluid media and confirmed to be reasonable for the first three vibration mode shapes.

  16. Use of Activated Charcoal for {sup 220}Rn Adsorption for Operations Associated with the Uranium Deposit in the Auxiliary Charcoal Bed at the Molten Salt Reactor Experiment Facility

    SciTech Connect

    Coleman, R.L.

    1999-03-01

    Measurements have been collected with the purpose of evaluating the effectiveness of activated charcoal for the removal of {sup 220}Rn from process off-gas at the Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory. A series of bench-scale tests were performed at superficial flow velocities of 10, 18, 24, and 33 cm/s (20, 35, 47, and 65 ft/min) with a continuous input concentration of {sup 220}Rn in the range of 9 x 10{sup 3} pCi/L. In addition, two tests were performed at the MSRE facility by flowing helium through the auxiliary charcoal bed uranium deposit. These tests were performed so that the adsorptive effectiveness could be evaluated with a relatively high concentration of {sup 220}Rn. In addition to measuring the effectiveness of activated charcoal as a {sup 220}Rn adsorption media, the source term for available {sup 220}Rn in the deposit is actually available for removal and that the relative activity of fission gases is very small when compared to {sup 220}Rn. The measurement data were then used to evaluate the expected effectiveness of a proposed charcoal adsorption bed consisting of a right circular cylinder having a diameter of 43 cm and a length of 91 cm (17 in. I.D. x 3 ft.). The majority of the measurement data predicts an overall 220Rn activity reduction factor of about 1 x 10{sup 9} for such a design; however, two measurements collected at a flow velocity of 18 cm/s (35 ft/min) indicated that the reduction factor could be as low as 1 x 10{sup 6}. The adsorptive capacity of the proposed trap was also evaluated to determine the expected life prior to degradation of performance. Taking a conservative vantage point during analysis, it was estimated that the adsorption effectiveness should not begin to deteriorate until a {sup 220}Rn activity on the order of 10{sup 10} Ci has been processed. It was therefore concluded that degradation of performance would likely occur as the result of causes other than filling by radon progeny.

  17. Use of Activated Charcoal for Rn-220 Adsorption for Operations Associated with the Uranium Deposit in the Auxiliary Charcoal Bed at the Molten Salt Reactor Experiment Facility

    SciTech Connect

    Coleman, R.L.

    1999-03-17

    Measurements have been collected with the purpose of evaluating the effectiveness of activated charcoal for the removal of {sup 220}Rn from process off-gas at the Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory. A series of bench-scale tests were performed at superficial flow velocities of 10, 18, 24, and 33 cm s{sup -1} (20, 35, 47, and 65 ft min{sup -1}) with a continuous input concentration of {sup 220}Rn in the range of 9 x 10{sup 3} pCi L{sup -1}. In addition, two tests were performed at the MSRE facility by flowing helium through the auxiliary charcoal bed uranium deposit. These tests were performed so that the adsorptive effectiveness could be evaluated with a relatively high concentration of {sup 220}Rn. In addition to measuring the effectiveness of activated charcoal as a {sup 220}Rn adsorption media, the source term for available {sup 220}Rn and gaseous fission products was evaluated and compared to what is believed to be present in the deposit. The results indicate that only a few percent of the total {sup 220}Rn in the deposit is actually available for removal and that the relative activity of fission gases is very small when compared to {sup 220}Rn. The measurement data were then used to evaluate the expected effectiveness of a proposed charcoal adsorption bed consisting of a right circular cylinder having a diameter of 43 cm and a length of 91 cm (17 in. I.D. x 3 ft.). The majority of the measurement data predicts an overall {sup 220}Rn activity reduction factor of about 1 x 10{sup 9} for such a design; however, two measurements collected at a flow velocity of 18 cm s{sup -1} (35 ft min{sup -1}) indicated that the reduction factor could be as low as 1 x 10{sup 6}. The adsorptive capacity of the proposed trap was also evaluated to determine the expected life prior to degradation of performance. Taking a conservative vantage point during analysis, it was estimated that the adsorption effectiveness should not begin to deteriorate

  18. Fluctuations in total antioxidant capacity, catalase activity, and hydrogen peroxide levels of follicular fluid during bovine folliculogenesis

    PubMed Central

    Gupta, Sajal; Choi, Audrey; Yu, Hope Y.; Czerniak, Suzanne M.; Holick, Emily A.; Paolella, Louis J.; Agarwal, Ashok; Combelles, Catherine M.H.

    2011-01-01

    Follicular fluid is an important environment for oocyte development, yet current knowledge regarding its in vivo oxidant and antioxidant levels remains limited. Examining follicular fluid oxidants and antioxidants will improve understanding of their changes in vivo and contribute to optimization of in vitro maturation conditions. The aim of our study was to consider select markers, namely catalase (CAT) enzyme activity, total antioxidant capacity (TAC), and hydrogen peroxide (H2O2) in follicular fluid samples (n=503) originating from bovine antral follicles. We measured the dynamic changes in two relevant antioxidant measures and one reactive oxygen species (ROS) through stages of bovine follicular development and the estrous cycle. CAT activity and H2O2 levels decreased significantly as follicle size increased, while TAC increased significantly as follicle size increased. Lower TAC and higher H2O2 in small follicles suggest increased ROS in the initial stages of folliculogenesis. Because CAT levels are highest in follicular fluid of small follicles in the setting of an overall low TAC, CAT may represent a dominant antioxidant defense in the initial stages of folliculogenesis. Future studies must focus on other reactive oxygen species and their various scavenger types during antral folliculogenesis. PMID:21635816

  19. Collaborative Strategy on Bed Bugs

    EPA Pesticide Factsheets

    The Collaborative Strategy on Bed Bugs was developed by the Federal Bed Bug Workgroup to clarify the federal role in bed bug control and highlight ways that government, community, academia and private industry can work together on bed bug issues.

  20. Space station propulsion test bed

    NASA Technical Reports Server (NTRS)

    Briley, G. L.; Evans, S. A.

    1989-01-01

    A test bed was fabricated to demonstrate hydrogen/oxygen propulsion technology readiness for the intital operating configuration (IOC) space station application. The test bed propulsion module and computer control system were delivered in December 1985, but activation was delayed until mid-1986 while the propulsion system baseline for the station was reexamined. A new baseline was selected with hydrogen/oxygen thruster modules supplied with gas produced by electrolysis of waste water from the space shuttle and space station. As a result, an electrolysis module was designed, fabricated, and added to the test bed to provide an end-to-end simulation of the baseline system. Subsequent testing of the test bed propulsion and electrolysis modules provided an end-to-end demonstration of the complete space station propulsion system, including thruster hot firings using the oxygen and hydrogen generated from electrolysis of water. Complete autonomous control and operation of all test bed components by the microprocessor control system designed and delivered during the program was demonstrated. The technical readiness of the system is now firmly established.

  1. Production of bio-oil rich in acetic acid and phenol from fast pyrolysis of palm residues using a fluidized bed reactor: Influence of activated carbons.

    PubMed

    Jeong, Jae-Yong; Lee, Uen-Do; Chang, Won-Seok; Jeong, Soo-Hwa

    2016-11-01

    In this study, palm residues were pyrolyzed in a bench-scale (3kg/h) fast pyrolysis plant equipped with a fluidized bed reactor and bio-oil separation system for the production of bio-oil rich in acetic acid and phenol. Pyrolysis experiments were performed to investigate the effects of reaction temperature and the types and amounts of activated carbon on the bio-oil composition. The maximum bio-oil yield obtained was approximately 47wt% at a reaction temperature of 515°C. The main compounds produced from the bio-oils were acetic acid, hydroxyacetone, phenol, and phenolic compounds such as cresol, xylenol, and pyrocatechol. When coal-derived activated carbon was applied, the acetic acid and phenol yields in the bio-oils reached 21 and 19wt%, respectively. Finally, bio-oils rich in acetic acid and phenol could be produced separately by using an in situ bio-oil separation system and activated carbon as an additive.

  2. Evaluating a strategy for maintaining nitrifier activity during long-term starvation in a moving bed biofilm reactor (MBBR) treating reverse osmosis concentrate.

    PubMed

    Ye, Liu; Hu, Shihu; Poussade, Yvan; Keller, Jurg; Yuan, Zhiguo

    2012-01-01

    A two-stage moving bed biofilm reactor (MBBR) was applied at the Bundamba advanced water treatment plant (AWTP) (Queensland, Australia) to treat the reverse osmosis concentrate (ROC) for inorganic nutrient removal. One of the operational challenges for the system was to cope with the large fluctuations of the ROC flow. This study investigated the decay rates of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) and biofilm detachment in MBBR during starvation for up to one month. An intermittent aeration strategy of 15 min aeration every 6 h was applied. This study also evaluated the activity recovery of both AOB and NOB after normal operation was resumed. The results showed that the activity loss of AOB and NOB was relatively minor (<20%) within 10 days of starvation, which ensured relatively quick recovery of ammonium removal when normal operation resumed. In contrast, the AOB and NOB activity loss reached 60-80% when the starvation time was longer than 20 days, resulting in slower recovery of ammonium removal after starvation. Starvation for less than 20 days didn't result in an apparent biomass detachment from carriers.

  3. Increase in ovulation rate after active immunization of sheep with inhibin partially purified from bovine follicular fluid.

    PubMed

    Henderson, K M; Franchimont, P; Lecomte-Yerna, M J; Hudson, N; Ball, K

    1984-09-01

    Four Romney ewes were actively immunized with a partially purified preparation of inhibin derived from bovine follicular fluid and their ovulation rates in four successive oestrous cycles were compared with those of four ewes receiving adjuvant alone. The ovulation rates of the ewes immunized with the inhibin preparation were significantly higher than those of the control ewes (2.06 +/- 0.16 (S.E.M.) vs 1.31 +/- 0.06 ovulations/ewe, n = 4). Plasma concentrations of FSH and LH, measured in blood samples taken three times a week for 11 weeks, during which time each ewe was immunized three times, were not significantly different between the two treatment groups. These results suggest that active immunization with inhibin-enriched follicular fluid may be a potential means of increasing fecundity in sheep.

  4. Antidiarrheal activity of wood creosote: inhibition of muscle contraction and enterotoxin-induced fluid secretion in rabbit small intestine.

    PubMed

    Ogata, N; Shibata, T

    2001-01-01

    Wood creosote has long been used as an antidiarrheal agent, but its mechanism of action is not well understood. To elucidate the mechanism of its antidiarrheal activity, we have addressed questions whether it inhibits fluid secretion induced by Escherichia coli heat-stable enterotoxin (STa) in rabbit jejunum in vivo, and whether it inhibits muscle contraction of isolated rabbit ileum ex vivo. Wood creosote (10-100 mg/l) instilled in a ligated loop of jejunum inhibited STa-induced fluid secretion (p < 0.05). It also inhibited the spontaneous phasic, acetylcholine-induced tonic and Ba2+-induced tonic contractions of longitudinal and circular muscles of ileum dose-dependently with IC(50) values of 130-530 mg/l. These data provide further evidence that the antidiarrheal activity of wood creosote is attributable to its antisecretory and antimotility effects.

  5. Mapping two-dimensional polar active fluids to two-dimensional soap and one-dimensional sandblasting

    NASA Astrophysics Data System (ADS)

    Chen, Leiming; Lee, Chiu Fan; Toner, John

    2016-07-01

    Active fluids and growing interfaces are two well-studied but very different non-equilibrium systems. Each exhibits non-equilibrium behaviour distinct from that of their equilibrium counterparts. Here we demonstrate a surprising connection between these two: the ordered phase of incompressible polar active fluids in two spatial dimensions without momentum conservation, and growing one-dimensional interfaces (that is, the 1+1-dimensional Kardar-Parisi-Zhang equation), in fact belong to the same universality class. This universality class also includes two equilibrium systems: two-dimensional smectic liquid crystals, and a peculiar kind of constrained two-dimensional ferromagnet. We use these connections to show that two-dimensional incompressible flocks are robust against fluctuations, and exhibit universal long-ranged, anisotropic spatio-temporal correlations of those fluctuations. We also thereby determine the exact values of the anisotropy exponent ζ and the roughness exponents χx,y that characterize these correlations.

  6. Mapping two-dimensional polar active fluids to two-dimensional soap and one-dimensional sandblasting.

    PubMed

    Chen, Leiming; Lee, Chiu Fan; Toner, John

    2016-07-25

    Active fluids and growing interfaces are two well-studied but very different non-equilibrium systems. Each exhibits non-equilibrium behaviour distinct from that of their equilibrium counterparts. Here we demonstrate a surprising connection between these two: the ordered phase of incompressible polar active fluids in two spatial dimensions without momentum conservation, and growing one-dimensional interfaces (that is, the 1+1-dimensional Kardar-Parisi-Zhang equation), in fact belong to the same universality class. This universality class also includes two equilibrium systems: two-dimensional smectic liquid crystals, and a peculiar kind of constrained two-dimensional ferromagnet. We use these connections to show that two-dimensional incompressible flocks are robust against fluctuations, and exhibit universal long-ranged, anisotropic spatio-temporal correlations of those fluctuations. We also thereby determine the exact values of the anisotropy exponent ζ and the roughness exponents χx,y that characterize these correlations.

  7. Activation of the renin-angiotensin system, specifically in the subfornical organ is sufficient to induce fluid intake.

    PubMed

    Coble, Jeffrey P; Cassell, Martin D; Davis, Deborah R; Grobe, Justin L; Sigmund, Curt D

    2014-08-15

    Increased activity of the renin-angiotensin system within the brain elevates fluid intake, blood pressure, and resting metabolic rate. Renin and angiotensinogen are coexpressed within the same cells of the subfornical organ, and the production and action of ANG II through the ANG II type 1 receptor in the subfornical organ (SFO) are necessary for fluid intake due to increased activity of the brain renin-angiotensin system. We generated an inducible model of ANG II production by breeding transgenic mice expressing human renin in neurons controlled by the synapsin promoter with transgenic mice containing a Cre-recombinase-inducible human angiotensinogen construct. Adenoviral delivery of Cre-recombinase causes SFO-selective induction of human angiotensinogen expression. Selective production of ANG II in the SFO results in increased water intake but did not change blood pressure or resting metabolic rate. The increase in water intake was ANG II type 1 receptor-dependent. When given a choice between water and 0.15 M NaCl, these mice increased total fluid and sodium, but not water, because of an increased preference for NaCl. When provided a choice between water and 0.3 M NaCl, the mice exhibited increased fluid, water, and sodium intake, but no change in preference for NaCl. The increase in fluid intake was blocked by an inhibitor of PKC, but not ERK, and was correlated with increased phosphorylated cyclic AMP response element binding protein in the subfornical organ. Thus, increased production and action of ANG II specifically in the subfornical organ are sufficient on their own to mediate an increase in drinking through PKC.