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Sample records for affinity removal system

  1. Stabilization of the Motion of Affine Systems

    NASA Astrophysics Data System (ADS)

    Babenko, E. A.; Martynyuk, A. A.

    2016-07-01

    Sufficient conditions for the stability of a nonlinear affine system subject to interval initial conditions are established. These conditions are based on new estimates of the norms of the solutions of the systems of perturbed equations of motion. This stabilization method is used to analyze an electromechanical system with permanent magnet

  2. Performance of dye-affinity beads for aluminium removal in magnetically stabilized fluidized bed

    PubMed Central

    Yavuz, Handan; Say, Ridvan; Andaç, Müge; Bayraktar, Necmi; Denizli, Adil

    2004-01-01

    Background Aluminum has recently been recognized as a causative agent in dialysis encephalopathy, osteodystrophy, and microcytic anemia occurring in patients with chronic renal failure who undergo long-term hemodialysis. Only a small amount of Al(III) in dialysis solutions may give rise to these disorders. Methods Magnetic poly(2-hydroxyethyl methacrylate) (mPHEMA) beads in the size range of 80–120 μm were produced by free radical co-polymerization of HEMA and ethylene dimethacrylate (EDMA) in the presence of magnetite particles (Fe3O4). Then, metal complexing ligand alizarin yellow was covalently attached onto mPHEMA beads. Alizarin yellow loading was 208 μmol/g. These beads were used for the removal of Al(III) ions from tap and dialysis water in a magnetically stabilized fluidized bed. Results Al(III) adsorption capacity of the beads decreased with an increase in the flow-rate. The maximum Al(III) adsorption was observed at pH 5.0. Comparison of batch and magnetically stabilized fluidized bed (MSFB) maximum capacities determined using Langmuir isotherms showed that dynamic capacity (17.5 mg/g) was somewhat higher than the batch capacity (11.8 mg/g). The dissociation constants for Al(III) were determined using the Langmuir isotherm equation to be 27.3 mM (MSFB) and 6.7 mM (batch system), indicating medium affinity, which was typical for pseudospecific affinity ligands. Al(III) ions could be repeatedly adsorbed and desorbed with these beads without noticeable loss in their Al(III) adsorption capacity. Conclusions Adsorption of Al(III) demonstrate the affinity of magnetic dye-affinity beads. The MSFB experiments allowed us to conclude that this inexpensive sorbent system may be an important alternative to the existing adsorbents in the removal of aluminium. PMID:15329149

  3. Non-affine elasticity in jammed systems

    NASA Astrophysics Data System (ADS)

    Maloney, Craig

    2006-03-01

    Symmetry dictates that perfect crystals should deform homogeneously, or affinely, under external load, and computing the elastic moduli from the underlying interaction potential is then straightforward. For disordered materials no such simple procedure exists, and recent numerical works have demonstrated that non-affine corrections can dramatically reduce the naive expectation for the shear modulus in a broad class of disordered systems and may control rigidity loss in the zero pressure limit in purely repulsive systems, i.e. the unjamming transition (c.f. [O'Hern et. al. PRE 68, 011306 (2003)]). We present numerical results and an analytical framework for the study of these non-affine corrections to the elastic response of disordered packings.

  4. The Shape Interaction Matrix-Based Affine Invariant Mismatch Removal for Partial-Duplicate Image Search.

    PubMed

    Lin, Yang; Lin, Zhouchen; Zha, Hongbin

    2017-02-01

    Mismatch removal is a key step in many computer vision problems. In this paper, we handle the mismatch removal problem by adopting shape interaction matrix (SIM). Given the homogeneous coordinates of the two corresponding point sets, we first compute the SIMs of the two point sets. Then, we detect the mismatches by picking out the most different entries between the two SIMs. Even under strong affine transformations, outliers, noises, and burstiness, our method can still work well. Actually, this paper is the first non-iterative mismatch removal method that achieves affine invariance. Extensive results on synthetic 2D points matching data sets and real image matching data sets verify the effectiveness, efficiency, and robustness of our method in removing mismatches. Moreover, when applied to partial-duplicate image search, our method reaches higher retrieval precisions with shorter time cost compared with the state-of-the-art geometric verification methods.

  5. System for removal of arsenic from water

    DOEpatents

    Moore, Robert C.; Anderson, D. Richard

    2004-11-23

    Systems for removing arsenic from water by addition of inexpensive and commonly available magnesium oxide, magnesium hydroxide, calcium oxide, or calcium hydroxide to the water. The hydroxide has a strong chemical affinity for arsenic and rapidly adsorbs arsenic, even in the presence of carbonate in the water. Simple and commercially available mechanical systems for removal of magnesium hydroxide particles with adsorbed arsenic from drinking water can be used, including filtration, dissolved air flotation, vortex separation, or centrifugal separation. A system for continuous removal of arsenic from water is provided. Also provided is a system for concentrating arsenic in a water sample to facilitate quantification of arsenic, by means of magnesium or calcium hydroxide adsorption.

  6. Efficient endotoxin removal with a new sanitizable affinity column: Affi-Prep Polymyxin.

    PubMed

    Talmadge, K W; Siebert, C J

    1989-08-04

    A new affinity column packing for removal of endotoxins has been prepared by coupling USP drug-quality polymyxin B to Affi-Prep, a novel synthetic macroporous polymer. Affi-Prep Polymyxin binds endotoxins from a number of different strains of gram-negative bacteria. Endotoxin binding is not significantly affected by 10 mg/ml of bovine serum albumin or human immunoglobulin G, by 1 mg/ml sodium dodecyl sulphate, or by 1 mg/ml deoxycholate. Affi-Prep Polymyxin is stable to treatment with 1.0 M sodium hydroxide, an important property for sanitizing the resin. The resin shows a high ligand stability, since no leakage of polymyxin B from the packing could be detected. Affi-Prep Polymyxin exhibited the highest endotoxin binding efficiency when compared with several commercial agarose affinity packings.

  7. Poly(hydroxyethyl methacrylate) based affinity membranes for in vitro removal of anti-dsDNA antibodies from SLE plasma.

    PubMed

    Uzun, Lokman; Yavuz, Handan; Osman, Bilgen; Celik, Hamdi; Denizli, Adil

    2010-07-01

    The preparation of polymeric membrane using affinity technology for application in blood filtration devices is described here. DNA attached poly(hydroxyethyl methacrylate) (PHEMA) based microporous affinity membrane was prepared for selective removal of anti-dsDNA antibodies from systemic lupus erythematosus (SLE) patient plasma in in vitro. In order to further increase blood-compatibility of affinity membrane, aminoacid based comonomer N-methacryloyl-L-alanine (MAAL) was included in the polymerization recipe. PHEMAAL membrane was produced by a photopolymerization technique and then characterized by swelling tests and scanning electron microscope (SEM) studies. Blood-compatibility tests were also performed. The water swelling ratio of PHEMAAL membrane increased significantly (133.2%) compared with PHEMA (58%). PHEMAAL membrane has large pores around in the range of 5-10 microm. All the clotting times increased when compared with PHEMA membrane. Loss of platelets and leukocytes was very low. DNA loading was 7.8 mg/g. There was a very low anti-dsDNA-antibody adsorption onto the plain PHEMAAL membrane, about 78 IU/g. The PHEMAAL-DNA membrane adsorbed anti-dsDNA-antibody in the range of 10-68 x 10(3)IU/g from SLE plasma. Anti-dsDNA-antibody concentration decreased significantly from 875 to 144 IU/ml with the time. Anti-dsDNA-antibodies could be repeatedly adsorbed and eluted without noticeable loss in the anti-dsDNA-antibody adsorption amount.

  8. Hot Spot Removal System: System description

    SciTech Connect

    1997-09-01

    Hazardous wastes contaminated with radionuclides, chemicals, and explosives exist across the Department of Energy complex and need to be remediated due to environmental concerns. Currently, an opportunity is being developed to dramatically reduce remediation costs and to assist in the acceleration of schedules associated with these wastes by deploying a Hot Spot Removal System. Removing the hot spot from the waste site will remove risk driver(s) and enable another, more cost effective process/option/remedial alternative (i.e., capping) to be applied to the remainder of the site. The Hot Spot Removal System consists of a suite of technologies that will be utilized to locate and remove source terms. Components of the system can also be used in a variety of other cleanup activities. This Hot Spot Removal System Description document presents technologies that were considered for possible inclusion in the Hot Spot Removal System, technologies made available to the Hot Spot Removal System, industrial interest in the Hot Spot Removal System`s subsystems, the schedule required for the Hot Spot Removal System, the evaluation of the relevant technologies, and the recommendations for equipment and technologies as stated in the Plan section.

  9. System for Removing Pollutants from Incinerator Exhaust

    NASA Technical Reports Server (NTRS)

    Wickham, David t.; Bahr, James; Dubovik, Rita; Gebhard, Steven C.; Lind, Jeffrey

    2008-01-01

    A system for removing pollutants -- primarily sulfur dioxide and mixed oxides of nitrogen (NOx) -- from incinerator exhaust has been demonstrated. The system is also designed secondarily to remove particles, hydrocarbons, and CO. The system is intended for use in an enclosed environment, for which a prior NOx-and-SO2-removal system designed for industrial settings would not be suitable.

  10. Space Station trash removal system

    NASA Technical Reports Server (NTRS)

    Petro, Andrew J. (Inventor)

    1993-01-01

    A trash removal system for space stations is described. The system is comprised of a disposable trash bag member and an attached, compacted large, lightweight inflatable balloon element. When the trash bag member is filled, the astronaut places the bag member into space through an airlock. Once in the vacuum of space, the balloon element inflates. Due to the large cross-sectional area of the balloon element relative to its mass, the combined balloon element and the trash bag member are slowed by atmospheric drag to a much greater extent than the Space Station's. The balloon element and bag member lose altitude and re-enter the atmosphere, and the elements and contents are destroyed by aerodynamic heating. The novelty of this system is in the unique method of using the vacuum of space and aerodynamic heating to dispose of waste material with a minimum of increase in orbital debris.

  11. Affinity hemodialysis for antiviral therapy. I. Removal of HIV-1 from cell culture supernatants, plasma, and blood.

    PubMed

    Tullis, Richard H; Duffin, R Paul; Zech, Marvin; Ambrus, Julian L

    2002-06-01

    We tested an affinity hemodialysis technique designed to efficiently remove HIV and toxic viral proteins from blood. Miniature polyethersulfone hollow-fiber dialysis cartridges (200-500 nm pore) were packed with anti-HIV antibodies covalently coupled to agarose beads and sealed inside the cartridge. Cell culture fluids, plasma, or infected blood (7-15 ml) containing HIV-1 were circulated over the cartridge at 0.7-10 ml/min and the rate of removal of HIV measured by PCR and p24 ELISA. The technique removed up to 98% of HIV-1 particles from cell culture supernatants. Affinity hemodialysis also efficiently captured cultured HIV from human blood plasma (90%) and native HIV from infected blood (83% to 100%). Viral capture followed first-order kinetics (t(1/2) = 2.8 h). Variations in antibody type, matrix linkage (protein G versus direct coupling), bead pore size, and temperature of operation (25-37 degrees C) had only small effects. Although some binding was nonspecific, direct binding to the immobilized antibodies appeared to be the predominant mechanism.

  12. High removal rate laser-based coating removal system

    DOEpatents

    Matthews, Dennis L.; Celliers, Peter M.; Hackel, Lloyd; Da Silva, Luiz B.; Dane, C. Brent; Mrowka, Stanley

    1999-11-16

    A compact laser system that removes surface coatings (such as paint, dirt, etc.) at a removal rate as high as 1000 ft.sup.2 /hr or more without damaging the surface. A high repetition rate laser with multiple amplification passes propagating through at least one optical amplifier is used, along with a delivery system consisting of a telescoping and articulating tube which also contains an evacuation system for simultaneously sweeping up the debris produced in the process. The amplified beam can be converted to an output beam by passively switching the polarization of at least one amplified beam. The system also has a personal safety system which protects against accidental exposures.

  13. Influence of affinity on antibody determination in microtiter ELISA systems

    SciTech Connect

    Peterman, J.H.; Voss, E.W. Jr.; Butler, J.E.

    1986-03-01

    Theoretically, all immunoassays are affinity (Ka) dependent when the product of the antibody (Ab) Ka and the free epitope concentration is less than 10. Thus, the degree of dependence on Ka depends on the concentration of available antigen in the system. The authors examined the binding of /sup 125/I-anti-fluorescein (a-FLU) monoclonal antibodies of different affinities to FLU-gelatin adsorbed on Immunlon 2 microtiter plates. Data obtained were in general agreement with our theoretical predictions; the percent of /sup 125/I-a-FLU which bound correlated with Ka, as did the shape of the titration curves. Measurement of 5 a-FLU monoclonals by the ELISA showed that the determination of Ab concentrations depends on the FLU-gelatin concentration, epitope density, and on the relationship between the Kas of test samples and the reference standard Ab preparation. Thus the ELISA is Ka dependent and should not be used routinely to estimate the absolute amount to Ab in unknown samples. However, the Ka dependency of the ELISA might provide a convenient assay for the estimation of the relative functional Ka (rfKa) of antibody preparations.

  14. Affinity-based in situ product removal coupled with co-immobilization of oily substrate and filamentous fungus.

    PubMed

    Dukler, A; Freeman, A

    1998-01-01

    In situ product removal (ISPR) involves actions taken for the fast removal of a product from the producing cell. ISPR is implemented to improve yield and productivity via minimization of product inhibition, minimization of product losses due to degradation or evaporation, and reduction of the number of subsequent downstream processing steps. Here we describe the implementation of affinity-based, specific ISPR as a crucial component of an integrative approach to problems associated with the biocatalytic production of a product exhibiting poor water solubility from an oily, water-insoluble precursor. Our integrative ISPR-based approach consists of co-immobilization of the oily substrate emulsion and the biocatalyst within bilayered alginate beads. A particulate-specific adsorbent, exhibiting high binding capacity of the product, is suspended in the reaction medium with periodical replacements. According to this approach, ISPR implementation is expected to shift the equilibration of product distribution between the co-immobilized oily substrate and the outer medium via specific product immobilization onto the added adsorbent. The product may subsequently be readily recovered via single-step final purification. This integrative approach was successfully demonstrated by the affinity-based ISPR of gamma-decalactone (4-decanolide). gamma-Decalactone was produced from castor oil via its beta-oxidation by the filamentous fungus Tyromyces sambuceus, co-immobilized with emulsified substrate within bilayered alginate beads. Product immobilization onto medium-suspended epichlorohydrin-crosslinked beta-cyclodextrin resulted in higher yield and easy pure product recovery.

  15. Designing Bioretention Systems to Improve Nitrogen Removal

    EPA Science Inventory

    Bioretention systems effectively remove many stormwater stressors, including oil/grease, heavy metals, phosphorus, and ammonium. However, reported nitrate removal performance is highly variable. Bioretention media is typically coarse-grained with low organic matter content, which...

  16. Robust adaptive control for a class of uncertain non-affine nonlinear systems using affine-type neural networks

    NASA Astrophysics Data System (ADS)

    Zhao, Shitie; Gao, Xianwen

    2016-08-01

    A robust adaptive control is proposed for a class of single-input single-output non-affine nonlinear systems. In order to approximate the unknown nonlinear function, a novel affine-type neural network is used, and then to compensate the approximation error and external disturbance a robust control term is employed. By Lyapunov stability analysis for the closed-loop system, it is proved that tracking errors asymptotically converge to zero. Moreover, an observer is designed to estimate the system states because all the states may not be available for measurements. Furthermore, the adaptation laws of neural networks and the robust controller are given out based on the Lyapunov stability theory. Finally, two simulation examples are presented to demonstrate the effectiveness of the proposed control method.

  17. Preparation of immuno-affinity membranes for cholesterol removal from human plasma.

    PubMed

    Denizli, Adil

    2002-06-05

    Anti-low density lipoprotein antibody (anti-LDL) immobilized polyhydroxyethylmethacrylate (pHEMA) based membrane was prepared for selective removal of cholesterol from hypercholesterolemic human plasma. In order to further increase blood-compatibility, a newly synthesized comonomer, methacryloylamidophenylalanine (MAPA) was included in the membrane formulation. p(HEMA-MAPA) membranes were produced by a photopolymerization and then characterized by swelling tests, SEM and contact angle studies. Blood-compatibility tests were also investigated. The water swelling ratio of the p(HEMA-MAPA) membrane increases significantly (133.2.9%) compared with pHEMA (58%). p(HEMA-MAPA) membranes have large pores around in the range of 5-10 microm. All the clotting times increased when compared with pHEMA membranes. Loss of platelets and leukocytes was very low. The maximum anti-LDL antibody immobilization was achieved around pH 7.0. Immobilization of anti-LDL antibody was 12.6 mg/ml. There was a very low non-specific cholesterol adsorption onto the plain p(HEMA-MAPA) membranes, about 0.36 mg/ml. Anti-LDL antibody immobilized membranes adsorbed in the range of 4.5-7.2 mg cholesterol/ml from hypercholesterolemic human plasma. Up to 95% of the adsorbed LDL antibody was desorbed. The adsorption-desorption cycle was repeated 10 times using the same membrane. There was no significant loss in the adsorption capacity.

  18. System for removing contaminants from plastic resin

    DOEpatents

    Bohnert, George W.; Hand, Thomas E.; DeLaurentiis, Gary M.

    2010-11-23

    A resin recycling system that produces essentially contaminant-free synthetic resin material in an environmentally safe and economical manner. The system includes receiving the resin in container form. A grinder grinds the containers into resin particles. The particles are exposed to a solvent in one or more solvent wash vessels, the solvent contacting the resin particles and substantially removing contaminants on the resin particles. A separator is used to separate the resin particles and the solvent. The resin particles are then placed in solvent removing element where they are exposed to a solvent removing agent which removes any residual solvent remaining on the resin particles after separation.

  19. C-Terminally fused affinity Strep-tag II is removed by proteolysis from recombinant human erythropoietin expressed in transgenic tobacco plants

    PubMed Central

    Kittur, Farooqahmed S.; Lalgondar, Mallikarjun; Hung, Chiu-Yueh; Sane, David C.

    2014-01-01

    Asialo-erythropoietin (asialo-EPO), a desialylated form of EPO, is a potent tissue-protective agent. Recently, we and others have exploited a low cost plant-based expression system to produce recombinant human asialo-EPO (asialo-rhuEPOP). To facilitate purification from plant extracts, Strep-tag II was engineered at the C-terminus of EPO. Although asialo-rhuEPOP was efficiently expressed in transgenic tobacco plants, affinity purification based on Strep-tag II did not result in the recovery of the protein. In this study, we investigated the stability of Strep-tag II tagged asialo-rhuEPOP expressed in tobacco plants to understand whether this fused tag is cleaved or inaccessible. Sequencing RT-PCR products confirmed that fused DNA sequences encoding Strep-tag II were properly transcribed, and three-dimensional protein structure model revealed that the tag must be fully accessible. However, Western blot analysis of leaf extracts and purified asialo-rhuEPOP revealed that the Strep-tag II was absent on the protein. Additionally, no peptide fragment containing Strep-tag II was identified in the LC-MS/MS analysis of purified protein further supporting that the affinity tag was absent on asialo-rhuEPOP. However, Strep-tag II was detected on asialo-rhuEPOP that was retained in the endoplasmic reticulum, suggesting that the Strep-tag II is removed during protein secretion or extraction. These findings together with recent reports that C-terminally fused Strep-tag II or IgG Fc domain are also removed from EPO in tobacco plants, suggest that its C-terminus may be highly susceptible to proteolysis in tobacco plants. Therefore, direct fusion of purification tags at the C-terminus of EPO should be avoided while expressing it in tobacco plants. PMID:25504272

  20. Removable Window System for Space Vehicles

    NASA Technical Reports Server (NTRS)

    Grady, James P. (Inventor)

    2015-01-01

    A window system for a platform comprising a window pane, a retention frame, and a biasing system. The window pane may be configured to contact a sealing system. The retention frame may be configured to contact the sealing system and hold the window pane against the support frame. The biasing system may be configured to bias the retention frame toward the support frame while the support frame and the retention frame are in a configuration that holds the window pane. Removal of the biasing system may cause the retention frame and the window pane to be removable.

  1. Mathematical modeling of the low and high affinity arabinose transport systems in Escherichia coli.

    PubMed

    Yildirim, Necmettin

    2012-04-01

    A mathematical model was developed for the low and high affinity arabinose transport systems in E. coli. The model is a system of three ordinary differential equations and takes the dynamics of mRNAs for the araE and araFGH proteins and the internal arabinose into account. Special attention was paid to estimate the model parameters from the literature. Our analysis and simulations suggest that the high affinity transport system helps the low affinity transport system to respond to high concentration of extracellular arabinose faster, whereas the high affinity transport system responds to a small amount of extracellular arabinose. Steady state analysis of the model also predicts that there is a regime for the extracellular concentration of arabinose where the arabinose system can show bistable behavior.

  2. Robotic Laser Coating Removal System

    DTIC Science & Technology

    2008-08-01

    completion of this evaluation a 6 kW CO2 laser from Rofin -Sinar was selected for use in the RLCRS. This laser provided the highest quality laser ...DATA AND ASSUMPTIONS................................................................B-1 iii LIST OF FIGURES Page Figure 1. Six kW CO2 laser ...for proposal (RFP) that was distributed throughout the laser industry. In response to this RFP, 15 laser systems (nine CO2 , three Nd:YAG, and three

  3. Affinity binding of antibodies to supermacroporous cryogel adsorbents with immobilized protein A for removal of anthrax toxin protective antigen.

    PubMed

    Ingavle, Ganesh C; Baillie, Les W J; Zheng, Yishan; Lis, Elzbieta K; Savina, Irina N; Howell, Carol A; Mikhalovsky, Sergey V; Sandeman, Susan R

    2015-05-01

    Polymeric cryogels are efficient carriers for the immobilization of biomolecules because of their unique macroporous structure, permeability, mechanical stability and different surface chemical functionalities. The aim of the study was to demonstrate the potential use of macroporous monolithic cryogels for biotoxin removal using anthrax toxin protective antigen (PA), the central cell-binding component of the anthrax exotoxins, and covalent immobilization of monoclonal antibodies. The affinity ligand (protein A) was chemically coupled to the reactive hydroxyl and epoxy-derivatized monolithic cryogels and the binding efficiencies of protein A, monoclonal antibodies to the cryogel column were determined. Our results show differences in the binding capacity of protein A as well as monoclonal antibodies to the cryogel adsorbents caused by ligand concentrations, physical properties and morphology of surface matrices. The cytotoxicity potential of the cryogels was determined by an in vitro viability assay using V79 lung fibroblast as a model cell and the results reveal that the cryogels are non-cytotoxic. Finally, the adsorptive capacities of PA from phosphate buffered saline (PBS) were evaluated towards a non-glycosylated, plant-derived human monoclonal antibody (PANG) and a glycosylated human monoclonal antibody (Valortim(®)), both of which were covalently attached via protein A immobilization. Optimal binding capacities of 108 and 117 mg/g of antibody to the adsorbent were observed for PANG attached poly(acrylamide-allyl glycidyl ether) [poly(AAm-AGE)] and Valortim(®) attached poly(AAm-AGE) cryogels, respectively, This indicated that glycosylation status of Valortim(®) antibody could significantly increase (8%) its binding capacity relative to the PANG antibody on poly(AAm-AGE)-protien-A column (p < 0.05). The amounts of PA which remained in the solution after passing PA spiked PBS through PANG or Valortim bound poly(AAm-AGE) cryogel were significantly (p < 0

  4. Low- and high-affinity transport systems for citric acid in the yeast Candida utilis.

    PubMed Central

    Cássio, F; Leáo, C

    1991-01-01

    Citric acid-grown cells of the yeast Candida utilis induced two transport systems for citric acid, presumably a proton symport and a facilitated diffusion system for the charged and the undissociated forms of the acid, respectively. Both systems could be observed simultaneously when the transport was measured at 25 degrees C with labelled citric acid at pH 3.5 with the following kinetic parameters: for the low-affinity system, Vmax, 1.14 nmol of undissociated citric acid s-1 mg (dry weight) of cells-1, and Km, 0.59 mM undissociated acid; for the high-affinity system, Vmax, 0.38 nmol of citrate s-1 mg (dry weight) of cells-1, and Km, 0.056 mM citrate. At high pH values (above 5.0), the low-affinity system was absent or not measurable. The two transport systems exhibited different substrate specificities. Isocitric acid was a competitive inhibitor of citric acid for the high-affinity system, suggesting that these tricarboxylic acids used the same transport system, while aconitic, tricarballylic, trimesic, and hemimellitic acids were not competitive inhibitors. With respect to the low-affinity system, isocitric acid, L-lactic acid, and L-malic acid were competitive inhibitors, suggesting that all of these mono-, di-, and tricarboxylic acids used the same low-affinity transport system. The two transport systems were repressed by glucose, and as a consequence diauxic growth was observed. Both systems were inducible, and not only citric acid but also lactic acid and malic acid may induce those transport systems. The induction of both systems was not dependent on the relative concentration of the anionic form(s) and of undissociated citric acid in the culture medium.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1664712

  5. Best approximation of functions in L{sub p} by polynomials on affine system

    SciTech Connect

    Terekhin, Pavel A

    2011-02-28

    Estimates of the best L{sub p}-approximation of functions by polynomials in an affine system (system of dilations and translations), which are similar to well-known estimates due to Ul'yanov and Golubov for approximations in the Haar system, are obtained. An analogue of A.F. Timan and M.F. Timan's inequality is shown to hold under certain conditions on the generating function of the affine system; this analogue fails for the Haar system for 1

  6. ASBESTOS PIPE-INSULATION REMOVAL ROBOT SYSTEM

    SciTech Connect

    Unknown

    2000-09-15

    This final topical report details the development, experimentation and field-testing activities for a robotic asbestos pipe-insulation removal robot system developed for use within the DOE's weapon complex as part of their ER and WM program, as well as in industrial abatement. The engineering development, regulatory compliance, cost-benefit and field-trial experiences gathered through this program are summarized.

  7. Dual-tagging system for the affinity purification of mammalian protein complexes

    SciTech Connect

    Giannone, Richard J; McDonald, W Hayes; Hurst, Gregory {Greg} B; Huang, Ying; Wu, Jun; Liu, Yie; Wang, Yisong

    2007-01-01

    Although affinity purification coupled with mass spectrometry (MS) provides a powerful tool to study protein-protein interactions, this strategy has encountered numerous difficulties when adapted to mammalian cells. Here we describe a Gateway{reg_sign}-compatible dual-tag affinity purification system that integrates regulatable expression, tetracysteine motifs, and various combinations of affinity tags to facilitate the cloning, detection, and purification of bait proteins and their interacting partners. Utilizing the human telomere binding protein TRF2 as a benchmark, we demonstrate bait protein recoveries upwards of approximately 16% from as little as 1-7 x 10{sup 7} cells and successfully identify known TRF2 interacting proteins, suggesting that our dual-tag affinity purification approach is a capable new tool for expanding the capacity to explore mammalian proteomic networks.

  8. Removal of Retired Alkali Metal Test Systems

    SciTech Connect

    Brehm, W. F.; Church, W. R.; Biglin, J. W.

    2003-02-26

    This paper describes the successful effort to remove alkali metals, alkali metal residues, and piping and structures from retired non-radioactive test systems on the Hanford Site. These test systems were used between 1965 and 1982 to support the Fast Flux Test Facility and the Liquid Metal Fast Breeder Reactor Program. A considerable volume of sodium and sodium-potassium alloy (NaK) was successfully recycled to the commercial sector; structural material and electrical material such as wiring was also recycled. Innovative techniques were used to safely remove NaK and its residues from a test system that could not be gravity-drained. The work was done safely, with no environmental issues or significant schedule delays.

  9. Pentek metal coating removal system: Baseline report

    SciTech Connect

    1997-07-31

    The Pentek coating removal technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The Pentek coating removal system consisted of the ROTO-PEEN Scaler, CORNER-CUTTER{reg_sign}, and VAC-PAC{reg_sign}. They are designed to remove coatings from steel, concrete, brick, and wood. The Scaler uses 3M Roto Peen tungsten carbide cutters while the CORNER-CUTTER{reg_sign} uses solid needles for descaling activities. These hand tools are used with the VAC-PAC{reg_sign} vacuum system to capture dust and debris as removal of the coating takes place. The safety and health evaluation during the testing demonstration focused on two main areas of exposure: dust and noise. Dust exposure minimal, but noise exposure was significant. Further testing for each exposure is recommended because of the environment where the testing demonstration took place. It is feasible that the dust and noise levels will be higher in an enclosed operating environment of different construction. In addition, other areas of concern found were arm-hand vibration, whole-body, ergonomics, heat stress, tripping hazards, electrical hazards, machine guarding, and lockout/tagout.

  10. Pegasus International, Inc. coating removal systems

    SciTech Connect

    1998-02-01

    The Pegasus Coating Removal System (PCRS) was demonstrated at Florida International University (FIU) where it was being evaluated for efficiency and cost. In conjunction with the FIU testing demonstration, a human factors assessment was conducted to assess the hazards and associated safety and health issues of concern for workers utilizing this technology. The PCRS is a chemical paste that is applied to the surface using a brush, roller, or airless sprayer. After the type of PCRS, thickness, and dwell time have been determined, a laminated backed material is placed on top of the chemical paste to slow down the drying process and to provide a mechanism to strip-off the chemical. After the dwell time is reached, the chemical substrate can be removed. Scrapers may be used to break-loose the layers as necessary or to break-loose the layers that are not removed when the laminated paper is picked up. Residue may also be cleaned off of the surface with a damp sponge with an agitating motion, absorbent sponges, or a vacuum, as needed. The paint and removal agent is then placed in drums for disposal at a later time. During the assessment sampling was conducted for organic vapors and general observational techniques were conducted for ergonomics. Recommendations for improved worker safety and health during application and removal of the PCRS include: (1) work practices that reflect avoidance of exposure or reducing the risk of exposure; (2) assuring all PPE and equipment are compatible with the chemicals being used; (3) work practices that reduce the worker`s need to walk on the slippery surface caused by the chemical or the use of special anti-slip soles; (4) careful control of overspray (if a spray application is used); and (5) the use of ergonomically designed long-handled tools to apply and remove the chemical (to alleviate some of the ergonomic concerns).

  11. Removal of the four C-terminal glycine-rich repeats enhances the thermostability and substrate binding affinity of barley beta-amylase.

    PubMed

    Ma, Y F; Eglinton, J K; Evans, D E; Logue, S J; Langridge, P

    2000-11-07

    Barley beta-amylase undergoes proteolytic cleavage in the C-terminal region after germination. The implication of the cleavage in the enzyme's characteristics is unclear. With purified native beta-amylases from both mature barley grain and germinated barley, we found that the beta-amylase from germinated barley had significantly higher thermostability and substrate binding affinity for starch than that from mature barley grain. To better understand the effect of the proteolytic cleavage on the enzyme's thermostability and substrate binding affinity for starch, recombinant barley beta-amylases with specific deletions at the C-terminal tail were generated. The complete deletion of the four C-terminal glycine-rich repeats significantly increased the enzyme's thermostability, but an incomplete deletion with one repeat remaining did not change the thermostability. Although different C-terminal deletions affect the thermostability differently, they all increased the enzyme's affinity for starch. The possible reasons for the increased thermostability and substrate binding affinity, due to the removal of the four C-terminal glycine-rich repeats, are discussed in terms of the three-dimensional structure of beta-amylase.

  12. West Valley waste removal system study

    SciTech Connect

    Janicek, G P

    1981-04-01

    This study addresses the specific task of removing high-level wastes from underground tanks at Western New York Nuclear Center and delivering them to an onsite waste solidification plant. It begins with a review of the design and construction features of the waste storage tanks pertinent to the waste removal task with particular emphasis on the unique and complex tank internals which severely complicate the task of removal. It follows with a review of tank cleaning techniques used and under study at both Hanford and Savannah River and previous studies proposing the use of these techniques at West Valley. It concludes from these reviews that existing techniques are not directly transferable to West Valley and that a new approach is required utilizing selected feature and attributes from existing methodology. The study also concludes, from an investigation of the constraints imposed by the processing facility, that waste removal will be intermittent, requiring batch transfer over the anticipated 3 years of processing operations. Based on these reviews and conclusions, the study proposes that the acid waste be processed first and that one of the 15,000-gallon acid tanks then be used for batch feeding the neutralized waste. The proposed system would employ commercially available pumping equipment to transfer the wastes from the batch tank to processing via existing process piping. A commercially available mixed-flow pump and eight turbine pumps would homogenize the neutralized waste in conjunction with eight custom-fabricated sluicers for periodic transfer to the batch tank.

  13. A tetra-layer microfluidic system for peptide affinity screening through integrated sample injection.

    PubMed

    Wang, Weizhi; Huang, Yanyan; Jin, Yulong; Liu, Guoquan; Chen, Yi; Ma, Huimin; Zhao, Rui

    2013-05-21

    A novel integrated microfluidic system was designed and fabricated for affinity peptide screening with in situ detection. A tetra-layer microfluidic hybrid chip containing two top eccentric diffluent layers, an inter-layer and a bottom screening layer, was developed as the core device of the system. The eccentric diffluent layers were ingeniously invented for the vertical sample delivery from 2 top-inlets into 12 bottom-inlets, which eliminated the use of excessive accessories and complicated pipelines currently used in other systems. By using six pH gradient generators, the magnetic bead-based screening in 36 parallel chambers was simultaneously carried out under 6 different pH conditions from 5.4 to 8.2. This allowed simultaneous screening of 6 compounds and each under 6 different pH conditions. The fabricated chip system was applied to screening of affinity peptides towards β-endorphin antibody. The affinities of the peptide ligands to the antibody were assessed by on-chip confocal detection. The results from the screening study using this system indicated that the pentapeptide with the sequence of YGGFL had the highest affinity towards β-endorphin antibody at pH 7.1, which was further confirmed by the ELISA assay using a 96-well plate format. This microfluidic screening system is automatic, low-cost and reusable for not only peptide screening but also other bioactive compounds screening towards target molecules.

  14. Biocathodic nitrous oxide removal in bioelectrochemical systems.

    PubMed

    Desloover, Joachim; Puig, Sebastià; Virdis, Bernardino; Clauwaert, Peter; Boeckx, Pascal; Verstraete, Willy; Boon, Nico

    2011-12-15

    Anthropogenic nitrous oxide (N(2)O) emissions represent up to 40% of the global N(2)O emission and are constantly increasing. Mitigation of these emissions is warranted since N(2)O is a strong greenhouse gas and important ozone-depleting compound. Until now, only physicochemical technologies have been applied to mitigate point sources of N(2)O, and no biological treatment technology has been developed so far. In this study, a bioelectrochemical system (BES) with an autotrophic denitrifying biocathode was considered for the removal of N(2)O. The high N(2)O removal rates obtained ranged between 0.76 and 1.83 kg N m(-3) net cathodic compartment (NCC) d(-1) and were proportional to the current production, resulting in cathodic coulombic efficiencies near 100%. Furthermore, our experiments suggested the active involvement of microorganisms as the catalyst for the reduction of N(2)O to N(2), and the optimal cathode potential ranged from -200 to 0 mV vs standard hydrogen electrode (SHE) in order to obtain high conversion rates. Successful operation of the system for more than 115 days with N(2)O as the sole cathodic electron acceptor strongly indicated that N(2)O respiration yielded enough energy to maintain the biological process. To our knowledge, this study provides for the first time proof of concept of biocathodic N(2)O removal at long-term without the need for high temperatures and expensive catalysts.

  15. Nitrogen removal in recirculated duckweed ponds system.

    PubMed

    Benjawan, L; Koottatep, T

    2007-01-01

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

  16. BOA: Pipe asbestos insulation removal robot system

    SciTech Connect

    Schempf, H.; Bares, J.; Schnorr, W.

    1995-12-31

    The BOA system is a mobile pipe-external robotic crawler used to remotely strip and bag asbestos-containing lagging and insulation materials (ACLIM) from various diameter pipes in (primarily) industrial installations. Steam and process lines within the DOE weapons complex warrant the use of a remote device due to the high labor costs and high level of radioactive contamination, making manual removal extremely costly and highly inefficient. Currently targeted facilities for demonstration and remediation are Fernald in Ohio and Oak Ridge in Tennessee.

  17. Novel affinity chromatographic system for the single-step purification of glycosaminoglycans from complex systems using volatile buffers.

    PubMed

    Hodson, B A; Pepper, D S; Dawes, J

    1991-04-19

    A new system for the isolation and purification of glycosaminoglycans (GAGs) and related molecules from complex systems such as plasma is described. Affinity chromatography which exploits the very high affinity between the polymeric base Polybrene and sulphated polysaccharides was used. A novel volatile buffer system composed of ammonium formate and formic acid, which allows the complete recovery of samples, was developed, and elution conditions were optimised for the separation and purification of GAGs of different charge densities. Using this system the losses associated with dialysis and desalting, frequently necessary preliminaries to further analysis, are avoided.

  18. A Lyapunov method for stability analysis of piecewise-affine systems over non-invariant domains

    NASA Astrophysics Data System (ADS)

    Rubagotti, Matteo; Zaccarian, Luca; Bemporad, Alberto

    2016-05-01

    This paper analyses stability of discrete-time piecewise-affine systems, defined on possibly non-invariant domains, taking into account the possible presence of multiple dynamics in each of the polytopic regions of the system. An algorithm based on linear programming is proposed, in order to prove exponential stability of the origin and to find a positively invariant estimate of its region of attraction. The results are based on the definition of a piecewise-affine Lyapunov function, which is in general discontinuous on the boundaries of the regions. The proposed method is proven to lead to feasible solutions in a broader range of cases as compared to a previously proposed approach. Two numerical examples are shown, among which a case where the proposed method is applied to a closed-loop system, to which model predictive control was applied without a-priori guarantee of stability.

  19. Piecewise affine models of chaotic attractors: The Rössler and Lorenz systems

    NASA Astrophysics Data System (ADS)

    Amaral, Gleison F. V.; Letellier, Christophe; Aguirre, Luis Antonio

    2006-03-01

    This paper proposes a procedure by which it is possible to synthesize Rössler [Phys. Lett. A 57, 397-398 (1976)] and Lorenz [J. Atmos. Sci. 20, 130-141 (1963)] dynamics by means of only two affine linear systems and an abrupt switching law. Comparison of different (valid) switching laws suggests that parameters of such a law behave as codimension one bifurcation parameters that can be changed to produce various dynamical regimes equivalent to those observed with the original systems. Topological analysis is used to characterize the resulting attractors and to compare them with the original attractors. The paper provides guidelines that are helpful to synthesize other chaotic dynamics by means of switching affine linear systems.

  20. The competitor-introduced Ggamma recruitment system, a new approach for screening affinity-enhanced proteins.

    PubMed

    Fukuda, Nobuo; Ishii, Jun; Tanaka, Tsutomu; Kondo, Akihiko

    2010-04-01

    We have developed a new approach based on the Ggamma recruitment system to screen affinity-enhanced proteins by expressing a binding competitor. The previously established Ggamma recruitment system is a yeast two-hybrid (Y2H) system that utilizes G-protein signaling, and is based on the fact that membrane localization of the G-protein gamma subunit (Ggamma) is essential for signal transduction in yeast. In the original Y2H system, an engineered Ggamma that lacks membrane localization upon deletion of the lipid modification site (Ggamma(cyto)) is produced, and a candidate protein with an artificial lipidation site and its counterpart fused with Ggamma(cyto) are expressed. As protein-protein interactions bring Ggamma(cyto) towards the plasma membrane, G-protein signaling can be activated, and the interaction is detected by various cellular responses as the readout. In the current study, we expressed a third cytosolic protein that competes with the candidate protein to specifically isolate affinity-enhanced mutants from a mutation library of the candidate protein. Enhancing the affinity of the protein candidate guides the counterpart-Ggamma(cyto) fusion protein towards the plasma membrane and activates signaling. Using mutants of the Z domain derived from Staphylococcus aureus protein A as candidate proteins or competitors, and the Fc portion of human immunoglobulin G (IgG) as the counterpart, we demonstrate that affinity-enhanced proteins can be effectively screened from a library containing a 10 000-fold excess of non-enhanced proteins. This new approach, called the competitor-introduced Ggamma recruitment system, will be useful for efficient discovery of rare valuable candidates hidden among excess ordinary ones.

  1. Expert systems guide biological phosphorus removal

    SciTech Connect

    Krichten, D.J.; Wilson, K.D.; Tracy, K.D. )

    1991-10-01

    There is a large body of knowledge regarding optimum control strategies for new secondary wastewater treatment technology using an anaerobic selector to provide biological phosphorus removal. However, because the selector technology is new and the concepts differ somewhat from those used in conventional activated sludge wastewater treatment, a method of communicating this knowledge to plant operators is needed. Traditional methods such as classroom training and operating manuals are of limited effectiveness. The commonplace availability and low cost of the personal computer (PC) makes it practical to use a computer program to communicate the type of information required to control a wastewater treatment plant. Knowledge-based systems technology, commonly referred to as expert systems (ES) technology, is easy to use, provides useful information regarding a consistent control strategy, relieves the anxiety associated with learning a new process,' and provides instruction for inexperienced personnel. ES technology does not require special formatted input and is therefore easily accessible. All information required by the program is readily available through routine laboratory analysis, common plant instrumentation, or direct user observation. The program was designed for all levels of computer users and will run on all IBM-compatible or Apple MacIntosh systems.

  2. A Novel Recombinant DNA System for High Efficiency Affinity Purification of Proteins in Saccharomyces cerevisiae

    PubMed Central

    Carrick, Brian H.; Hao, Linxuan; Smaldino, Philip J.; Engelke, David R.

    2015-01-01

    Isolation of endogenous proteins from Saccharomyces cerevisiae has been facilitated by inserting encoding polypeptide affinity tags at the C-termini of chromosomal open reading frames (ORFs) using homologous recombination of DNA fragments. Tagged protein isolation is limited by a number of factors, including high cost of affinity resins for bulk isolation and low concentration of ligands on the resin surface, leading to low isolation efficiencies and trapping of contaminants. To address this, we have created a recombinant “CelTag” DNA construct from which PCR fragments can be created to easily tag C-termini of S. cerevisiae ORFs using selection for a nat1 marker. The tag has a C-terminal cellulose binding module to be used in the first affinity step. Microgranular cellulose is very inexpensive and has an effectively continuous ligand on its surface, allowing rapid, highly efficient purification with minimal background. Cellulose-bound proteins are released by specific cleavage of an included site for TEV protease, giving nearly pure product. The tag can be lifted from the recombinant DNA construct either with or without a 13x myc epitope tag between the target ORF and the TEV protease site. Binding of CelTag protein fusions to cellulose is stable to high salt, nonionic detergents, and 1 M urea, allowing stringent washing conditions to remove loosely associated components, as needed, before specific elution. It is anticipated that this reagent could allow isolation of protein complexes from large quantities of yeast extract, including soluble, membrane-bound, or nucleic acid-associated assemblies. PMID:26715090

  3. A Novel Recombinant DNA System for High Efficiency Affinity Purification of Proteins in Saccharomyces cerevisiae.

    PubMed

    Carrick, Brian H; Hao, Linxuan; Smaldino, Philip J; Engelke, David R

    2015-12-29

    Isolation of endogenous proteins from Saccharomyces cerevisiae has been facilitated by inserting encoding polypeptide affinity tags at the C-termini of chromosomal open reading frames (ORFs) using homologous recombination of DNA fragments. Tagged protein isolation is limited by a number of factors, including high cost of affinity resins for bulk isolation and low concentration of ligands on the resin surface, leading to low isolation efficiencies and trapping of contaminants. To address this, we have created a recombinant "CelTag" DNA construct from which PCR fragments can be created to easily tag C-termini of S. cerevisiae ORFs using selection for a nat1 marker. The tag has a C-terminal cellulose binding module to be used in the first affinity step. Microgranular cellulose is very inexpensive and has an effectively continuous ligand on its surface, allowing rapid, highly efficient purification with minimal background. Cellulose-bound proteins are released by specific cleavage of an included site for TEV protease, giving nearly pure product. The tag can be lifted from the recombinant DNA construct either with or without a 13x myc epitope tag between the target ORF and the TEV protease site. Binding of CelTag protein fusions to cellulose is stable to high salt, nonionic detergents, and 1 M urea, allowing stringent washing conditions to remove loosely associated components, as needed, before specific elution. It is anticipated that this reagent could allow isolation of protein complexes from large quantities of yeast extract, including soluble, membrane-bound, or nucleic acid-associated assemblies.

  4. Identification of piecewise affine systems based on fuzzy PCA-guided robust clustering technique

    NASA Astrophysics Data System (ADS)

    Khanmirza, Esmaeel; Nazarahari, Milad; Mousavi, Alireza

    2016-12-01

    Hybrid systems are a class of dynamical systems whose behaviors are based on the interaction between discrete and continuous dynamical behaviors. Since a general method for the analysis of hybrid systems is not available, some researchers have focused on specific types of hybrid systems. Piecewise affine (PWA) systems are one of the subsets of hybrid systems. The identification of PWA systems includes the estimation of the parameters of affine subsystems and the coefficients of the hyperplanes defining the partition of the state-input domain. In this paper, we have proposed a PWA identification approach based on a modified clustering technique. By using a fuzzy PCA-guided robust k-means clustering algorithm along with neighborhood outlier detection, the two main drawbacks of the well-known clustering algorithms, i.e., the poor initialization and the presence of outliers, are eliminated. Furthermore, this modified clustering technique enables us to determine the number of subsystems without any prior knowledge about system. In addition, applying the structure of the state-input domain, that is, considering the time sequence of input-output pairs, provides a more efficient clustering algorithm, which is the other novelty of this work. Finally, the proposed algorithm has been evaluated by parameter identification of an IGV servo actuator. Simulation together with experiment analysis has proved the effectiveness of the proposed method.

  5. Combined experimental and theoretical study on the removal of pollutant compounds by peroxidases: affinity and reactivity toward a bioremediation catalyst.

    PubMed

    Silva, Maria Cristina; Torres, Juliana Arriel; Castro, Alexandre A; da Cunha, Elaine F F; Alves de Oliveira, Luiz Carlos; Corrêa, Angelita Duarte; Ramalho, Teodorico C

    2016-09-01

    Water pollution is a significant and growing problem throughout the world, especially in developing countries. In order to minimize environmental problems, catalysts have increasingly been designed to remove pollutants from the water. In an attempt to innovate by the creation of new low-cost alternatives to efficiently remove pollutants, the enzymatic treatment has been intensely studied for this purpose. Reactions catalyzed by enzymes are able to perform specific treatments, commonly with high rates of the final products. With this, the enzyme, peroxidase, is a promising candidate as a bioremediation catalyst. The efficiency of oxidoreductive enzymes, such as horseradish peroxidase (HRP) and soybean peroxidase (SP) have been studied, given that their performance depends on the substrate. In this investigation, experimental techniques and theoretical calculations have been employed in order to investigate the oxidative process for the ferulic acid and bromophenol blue dyes, performed by HRP and SP. Both enzymes showed a comparable behavior with respect to ferulic acid substrate. On the other hand, by utilizing bromophenol blue dye as a substrate, the behavior of the employed catalysts was significantly different. Experimental data have shown that HRP was more active toward bromophenol blue when compared to ferulic acid, being more rapidly degraded by the HRP enzyme. This tendency was confirmed by our theoretical docking, PM6 semi-empirical method, and DFT calculation results, in which the interaction, binding energies, and transition states were determined.

  6. Affine Maps of the Polarization Vector for Quantum Systems of Arbitrary Dimension

    NASA Astrophysics Data System (ADS)

    Byrd, Mark; Bishop, C. Allen; Ou, Yong-Cheng

    2011-03-01

    The operator-sum decomposition (OS) of a mapping from one density matrix to another has many applications in quantum information science. To this mapping there corresponds an affine map which provides a geometric description of the density matrix in terms of the polarization vector representation. This has been thoroughly explored for qubits since the components of the polarization vector are measurable quantities (corresponding to expectation values of Hermitian operators) and also because it enables the description of map domains geometrically. Here we extend the OS-affine map correspondence to qudits, briefly discuss general properties of the map, the form for particular important cases, and provide several explicit results for qutrit maps. We use the affine map and a singular-value-like decomposition, to find positivity constraints that provide a symmetry for small polarization vector magnitudes (states which are closer to the maximally mixed state) which is broken as the polarization vector increases in magnitude (a state becomes more pure). The dependence of this symmetry on the magnitude of the polarization vector implies the polar decomposition of the map can not be used as it can for the qubit case. However, it still leads us to a connection between positivity and purity for general d-state systems. This material is based upon work supported by NSF-Grant No. 0545798 to MSB.

  7. High affinity binding of [3H]-tyramine in the central nervous system.

    PubMed Central

    Vaccari, A.

    1986-01-01

    Optimum assay conditions for the association of [3H]-para-tyramine [( 3H]-pTA) with rat brain membranes were characterized, and a saturable, reversible, drug-specific, and high affinity binding mechanism for this trace amine was revealed. The binding capacity (Bmax) for [3H]-pTA in the corpus striatum was approximately 30 times higher than that in the cerebellum, with similar dissociation constants (KD). The binding process of [3H]-pTA involved the dopamine system, inasmuch as (a) highest binding capacity was associated with dopamine-rich regions; (b) dopamine and pTA equally displaced specifically bound [3H]-pTA; (c) there was a severe loss in striatal binding capacity for [3H]-pTA and, reportedly, for [3H]-dopamine, following unilateral nigrostriatal lesion; (d) acute in vivo reserpine treatment markedly decreased the density of [3H]-pTA and, reportedly, of [3H]-dopamine binding sites. In competition experiments [3H]-pTA binding sites, though displaying nanomolar affinity for dopamine, revealed micromolar affinities for the dopamine agonists apomorphine and pergolide, and for several dopamine antagonists, while having very high affinity for reserpine, a marker for the catecholamine transporter in synaptic vesicles. The binding process of [3H]-pTA was both energy-dependent (ouabain-sensitive), and ATP-Mg2+-insensitive; furthermore, the potencies of various drugs in competing for [3H]-pTA binding to rat striatal membranes correlated well (r = 0.96) with their reported potencies in inhibiting [3H]-dopamine uptake into striatal synaptosomes. It is concluded that [3H]-pTA binds at a site located on/within synaptic vesicles where it is involved in the transport mechanism of dopamine. PMID:3801770

  8. Passive shut-down heat removal system

    DOEpatents

    Hundal, Rolv; Sharbaugh, John E.

    1988-01-01

    An improved shut-down heat removal system for a liquid metal nuclear reactor of the type having a vessel for holding hot and cold pools of liquid sodium is disclosed herein. Generally, the improved system comprises a redan or barrier within the reactor vessel which allows an auxiliary heat exchanger to become immersed in liquid sodium from the hot pool whenever the reactor pump fails to generate a metal-circulating pressure differential between the hot and cold pools of sodium. This redan also defines an alternative circulation path between the hot and cold pools of sodium in order to equilibrate the distribution of the decay heat from the reactor core. The invention may take the form of a redan or barrier that circumscribes the inner wall of the reactor vessel, thereby defining an annular space therebetween. In this embodiment, the bottom of the annular space communicates with the cold pool of sodium, and the auxiliary heat exchanger is placed in this annular space just above the drawn-down level that the liquid sodium assumes during normal operating conditions. Alternatively, the redan of the invention may include a pair of vertically oriented, concentrically disposed standpipes having a piston member disposed between them that operates somewhat like a pressure-sensitive valve. In both embodiments, the cessation of the pressure differential that is normally created by the reactor pump causes the auxiliary heat exchanger to be immersed in liquid sodium from the hot pool. Additionally, the redan in both embodiments forms a circulation flow path between the hot and cold pools so that the decay heat from the nuclear core is uniformly distributed within the vessel.

  9. Enzyme- and affinity biomolecule-mediated polymerization systems for biological signal amplification and cell screening.

    PubMed

    Malinowska, Klara H; Nash, Michael A

    2016-06-01

    Enzyme-mediated polymerization and polymerization-based signal amplification have emerged as two closely related techniques that are broadly applicable in the nanobio sciences. We review recent progress on polymerization systems mediated by biological molecules (e.g., affinity molecules and enzymes), and highlight newly developed formats and configurations of these systems to perform such tasks as non-instrumented biodetection, synthesis of core-shell nanomaterials, isolation of rare cells, and high-throughput screening. We discuss useful features of biologically mediated polymerization systems, such as multiple mechanisms of amplification (e.g., enzymatic, radical chain propagation), and the ability to localize structures at interfaces and at cell surfaces with microscopic spatial confinement. We close with a perspective on desirable improvements that need to be addressed to adapt these molecular systems to future applications.

  10. Identification of high- and low-affinity NGF receptors during development of the chicken central nervous system

    SciTech Connect

    Escandon, E.; Chao, M.V. )

    1990-12-01

    In order to study regulation of the nerve growth factor (NGF) receptor during embryogenesis in chick brain, we have used affinity crosslinking of tissues with {sup 125}I-NGF. NGF interacts with high- and low-affinity receptors; high-affinity receptors are required for the majority of NGF's actions. Most measurements of receptor levels do not distinguish between high- and low-affinity forms of the receptor. We have used the lipophilic crosslinking agent HSAB to identify the high-affinity, functional receptor during development of the chicken central nervous system. A peak of expression during Embryonic Days 5-10 was detected in all regions of the chicken central nervous system, but, shortly after birth, only the cerebellar region displays significant levels of NGF receptor protein. The time course of expression confirms the dramatic regulation of the NGF receptor gene during defined embryonic periods. The detection of high-affinity NGF receptors in brain and neural retina provides strong evidence that NGF is involved in essential ontogenetic events in the development of the chicken central nervous system.

  11. Fluidized bed gasification ash reduction and removal system

    SciTech Connect

    Schenone, C.E.; Rosinski, J.

    1984-02-28

    In a fluidized bed gasification system, an ash removal system is disclosed to reduce the particulate ash to a maximum size or smaller, allow the ash to cool to a temperature lower than the gasifier and remove the ash from the gasifier system. The system consists of a crusher, a container containing level probes and a means for controlling the rotational speed of the crusher based on the level of ash within the container.

  12. Fluidized bed gasification ash reduction and removal system

    DOEpatents

    Schenone, Carl E.; Rosinski, Joseph

    1984-02-28

    In a fluidized bed gasification system an ash removal system to reduce the particulate ash to a maximum size or smaller, allow the ash to cool to a temperature lower than the gasifier and remove the ash from the gasifier system. The system consists of a crusher, a container containing level probes and a means for controlling the rotational speed of the crusher based on the level of ash within the container.

  13. Construction of a dual-tag system for gene expression, protein affinity purification and fusion protein processing.

    PubMed

    Motejadded, Hassan; Altenbuchner, Josef

    2009-04-01

    An E. coli vector system was constructed which allows the expression of fusion genes via a L: -rhamnose-inducible promotor. The corresponding fusion proteins consist of the maltose-binding protein and a His-tag sequence for affinity purification, the Saccharomyces cerevisiae Smt3 protein for protein processing by proteolytic cleavage and the protein of interest. The Smt3 gene was codon-optimized for expression in E. coli. In a second rhamnose-inducible vector, the S. cerevisiae Ulp1 protease gene for processing Smt3 fusion proteins was fused in the same way to maltose-binding protein and His-tag sequence but without the Smt3 gene. The enhanced green fluorescent protein (eGFP) was used as reporter and protein of interest. Both fusion proteins (MalE-6xHis-Smt3-eGFP and MalE-6xHis-Ulp1) were efficiently produced in E. coli and separately purified by amylose resin. After proteolytic cleavage the products were applied to a Ni-NTA column to remove protease and tags. Pure eGFP protein was obtained in the flow-through of the column in a yield of around 35% of the crude cell extract.

  14. Wash water solids removal system study

    NASA Technical Reports Server (NTRS)

    1974-01-01

    During wash water purification, surfactants tend to precipitate and foul the RO membranes, causing water flux decline and loss of salt rejection. The use of 165 to 190 ppm ferric chloride and optionally 0.25 to 1.0 ppm polymeric flocculate precipitates 92 to 96 percent of the surfactant from an Olive Leaf Soap based wash water. Crossflow filtration and pressure filtration yield good soap rejection at high water flux rates. Post-treatment of the chemically pretreated and filtered wash water with activated charcoal removes the residual soap down to an undetectable level.

  15. Disposable and removable nucleic acid extraction and purification cartridges for automated flow-through systems

    DOEpatents

    Regan, John Frederick

    2014-09-09

    Removable cartridges are used on automated flow-through systems for the purpose of extracting and purifying genetic material from complex matrices. Different types of cartridges are paired with specific automated protocols to concentrate, extract, and purifying pathogenic or human genetic material. Their flow-through nature allows large quantities sample to be processed. Matrices may be filtered using size exclusion and/or affinity filters to concentrate the pathogen of interest. Lysed material is ultimately passed through a filter to remove the insoluble material before the soluble genetic material is delivered past a silica-like membrane that binds the genetic material, where it is washed, dried, and eluted. Cartridges are inserted into the housing areas of flow-through automated instruments, which are equipped with sensors to ensure proper placement and usage of the cartridges. Properly inserted cartridges create fluid- and air-tight seals with the flow lines of an automated instrument.

  16. Optimality of affine control system of several species in competition on a sequential batch reactor

    NASA Astrophysics Data System (ADS)

    Rodríguez, J. C.; Ramírez, H.; Gajardo, P.; Rapaport, A.

    2014-09-01

    In this paper, we analyse the optimality of affine control system of several species in competition for a single substrate on a sequential batch reactor, with the objective being to reach a given (low) level of the substrate. We allow controls to be bounded measurable functions of time plus possible impulses. A suitable modification of the dynamics leads to a slightly different optimal control problem, without impulsive controls, for which we apply different optimality conditions derived from Pontryagin principle and the Hamilton-Jacobi-Bellman equation. We thus characterise the singular trajectories of our problem as the extremal trajectories keeping the substrate at a constant level. We also establish conditions for which an immediate one impulse (IOI) strategy is optimal. Some numerical experiences are then included in order to illustrate our study and show that those conditions are also necessary to ensure the optimality of the IOI strategy.

  17. Development of Carbon Dioxide Removal Systems for Advanced Exploration Systems

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Trinh, Diep; Gostowski, Rudy; King, Eric; Mattox, Emily M.; Watson, David; Thomas, John

    2012-01-01

    "NASA's Advanced Exploration Systems (AES) program is pioneering new approaches for rapidly developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond Earth orbit" (NASA 2012). These forays beyond the confines of earth's gravity will place unprecedented demands on launch systems. They must not only blast out of earth's gravity well as during the Apollo moon missions, but also launch the supplies needed to sustain a crew over longer periods for exploration missions beyond earth's moon. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. Current efforts are focused on improving the current state-of-the-art systems utilizing fixed beds of sorbent pellets by seeking more robust pelletized sorbents, evaluating structured sorbents, and examining alternate bed configurations to improve system efficiency and reliability. These development efforts combine testing of sub-scale systems and multi-physics computer simulations to evaluate candidate approaches, select the best performing options, and optimize the configuration of the selected approach, which is then implemented in a full-scale integrated atmosphere revitalization test. This paper describes the carbon dioxide (CO2) removal hardware design and sorbent screening and characterization effort in support of the Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project within the AES program. A companion paper discusses development of atmosphere revitalization models and simulations for this project.

  18. Treatment System for Removing Halogenated Compounds from Contaminated Sources

    NASA Technical Reports Server (NTRS)

    Quinn, Jacqueline W. (Inventor); Clausen, Christian A. (Inventor); Yestrebsky, Cherie L. (Inventor)

    2015-01-01

    A treatment system and a method for removal of at least one halogenated compound, such as PCBs, found in contaminated systems are provided. The treatment system includes a polymer blanket for receiving at least one non-polar solvent. The halogenated compound permeates into or through a wall of the polymer blanket where it is solubilized with at least one non-polar solvent received by said polymer blanket forming a halogenated solvent mixture. This treatment system and method provides for the in situ removal of halogenated compounds from the contaminated system. In one embodiment, the halogenated solvent mixture is subjected to subsequent processes which destroy and/or degrade the halogenated compound.

  19. Integral reinforcement learning for continuous-time input-affine nonlinear systems with simultaneous invariant explorations.

    PubMed

    Lee, Jae Young; Park, Jin Bae; Choi, Yoon Ho

    2015-05-01

    This paper focuses on a class of reinforcement learning (RL) algorithms, named integral RL (I-RL), that solve continuous-time (CT) nonlinear optimal control problems with input-affine system dynamics. First, we extend the concepts of exploration, integral temporal difference, and invariant admissibility to the target CT nonlinear system that is governed by a control policy plus a probing signal called an exploration. Then, we show input-to-state stability (ISS) and invariant admissibility of the closed-loop systems with the policies generated by integral policy iteration (I-PI) or invariantly admissible PI (IA-PI) method. Based on these, three online I-RL algorithms named explorized I-PI and integral Q -learning I, II are proposed, all of which generate the same convergent sequences as I-PI and IA-PI under the required excitation condition on the exploration. All the proposed methods are partially or completely model free, and can simultaneously explore the state space in a stable manner during the online learning processes. ISS, invariant admissibility, and convergence properties of the proposed methods are also investigated, and related with these, we show the design principles of the exploration for safe learning. Neural-network-based implementation methods for the proposed schemes are also presented in this paper. Finally, several numerical simulations are carried out to verify the effectiveness of the proposed methods.

  20. Nutrients removal and recovery in bioelectrochemical systems: a review.

    PubMed

    Kelly, Patrick T; He, Zhen

    2014-02-01

    Nutrient removal and recovery has received less attention during the development of bioelectrochemical systems (BES) for energy efficient wastewater treatment, but it is a critical issue for sustainable wastewater treatment. Both nitrogen and phosphorus can be removed and/or recovered in a BES through involving biological processes such as nitrification and bioelectrochemical denitrification, the NH4(+)/NH3 couple affected by the electrolyte pH, or precipitating phosphorus compounds in the high-pH zone adjacent a cathode electrode. This paper has reviewed the nutrients removal and recovery in various BES including microbial fuel cells and microbial electrolysis cells, discussed the influence factors and potential problems, and identified the key challenges for nitrogen and phosphorus removal/recovery in a BES. It expects to give an informative overview of the current development, and to encourage more thinking and investigation towards further development of efficient processes for nutrient removal and recovery in a BES.

  1. Orbital debris removal and salvage system

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Four Texas A&M University projects are discussed. The first project is a design to eliminate a majority of orbital debris. The Orbital Debris and Salvage System will push the smaller particles into lower orbits where their orbits will decay at a higher rate. This will be done by momentum transfer via laser. The salvageable satellites will be delivered to the Space Station by an Orbital Transfer Vehicle. The rest of the debris will be collected by Salvage I. The second project is the design of a space based satellite system to prevent the depletion of atmospheric ozone. The focus is on ozone depletion in the Antarctic. The plan is to use an orbiting solar array system designed to transmit microwaves at a frequency of 22 GHz over the region in order to dissipate polar stratospheric clouds that form during the months beginning in August and ending in October. The third project, Project Poseidon, involves a conceptual design of a space based hurricane control system consisting of a network of 21 low-orbiting laser platforms arranged in three rings designed to heat the upper atmosphere of a developing tropical depression. Fusion power plants are proposed to provide power for the lasers. The fourth project, Project Donatello, involves a proposed Mars exploration initiative for the year 2050. The project is a conceptual design for a futuristic superfreighter that will transport large numbers of people and supplies to Mars for the construction of a full scale scientific and manufacturing complex.

  2. Laser Systems for Orbital Debris Removal

    SciTech Connect

    Rubenchik, A. M.; Barty, C. P. J.; Beach, R. J.; Erlandson, A. C.; Caird, J. A.

    2010-10-08

    The use of a ground based laser for space debris cleaning was investigated by the ORION project in 1996. Since that study the greatest technological advance in the development of high energy pulsed laser systems has taken place within the NIF project at LLNL. The proposed next laser system to follow the NIF at LLNL will be a high rep rate version of the NIF based on diode-pumping rather than flashlamp excitation; the so called 'LIFE' laser system. Because a single 'LIFE' beamline could be built up in a few year time frame, and has performance characteristics relevant to the space debris clearing problem, such a beamline could enable a near term demonstration of space debris cleaning. Moreover, the specifics of debris cleaning make it possible to simplify the LIFE laser beyond what is required for a fusion drive laser, and so substantially reduce its cost. Starting with the requirements for laser intensity on the target, and then considering beam delivery, we will flow back the laser requirements needed for space debris cleaning. Using these derived requirements we will then optimize the pulse duration, the operational regime, and the output pulse energy of the laser with a focus of simplifying its overall design. Anticipated simplifications include operation in the heat capacity regime, eliminating cooling requirements on the laser gain slabs, and relaxing B-integral and birefrigence requirements.

  3. Laser Systems for Orbital Debris Removal

    SciTech Connect

    Rubenchik, A M; Barty, C P; Beach, R J; Erlandson, A C; Caird, J A

    2010-02-05

    The use of a ground based laser for space debris cleaning was investigated by the ORION project in 1996. Since that study the greatest technological advance in the development of high energy pulsed laser systems has taken place within the NIF project at LLNL. The proposed next laser system to follow the NIF at LLNL will be a high rep rate version of the NIF based on diode-pumping rather than flashlamp excitation; the so called 'LIFE' laser system. Because a single 'LIFE' beamline could be built up in a few year time frame, and has performance characteristics relevant to the space debris clearing problem, such a beamline could enable a near term demonstration of space debris cleaning. Moreover, the specifics of debris cleaning make it possible to simplify the LIFE laser beyond what is required for a fusion drive laser, and so substantially reduce its cost. Starting with the requirements for laser intensity on the target, and then considering beam delivery, we will flow back the laser requirements needed for space debris cleaning. Using these derived requirements we will then optimize the pulse duration, the operational regime, and the output pulse energy of the laser with a focus of simplifying its overall design. Anticipated simplifications include operation in the heat capacity regime, eliminating cooling requirements on the laser gain slabs, and relaxing B-integral and birefrigence requirements.

  4. Operability test procedure [Tank] 241-SY-101 equipment removal system

    SciTech Connect

    Mast, J.C.

    1994-12-08

    The 241-SY-101 equipment removal system (ERS) consists of components, equipment, instrumentation and procedures that will provide the means to disconnect, retrieve, contain, load and transport the Mitigation Pump Assembly (MPA) from waste Tank 241-SY-101 to the Central Waste Complex (CWC). The Operability Test Procedure (OTP) will test the interfaces between ERS components and will rehearse the procedure for MPA removal and transportation to the extent they can be mocked-up at the CTF (Cold Test Facility). At the conclusion of the OTP, the ERS components and equipment will be removed from the CTF, entered into the Component Based Recall System (CBRS), and stored until needed for actual MPA removal and transportation.

  5. How to market an affiliation. St. Elizabeth Hospital and Mercy Medical Center affiliate to create Affinity Health System.

    PubMed

    1996-01-01

    When Wisconsin's St. Elizabeth Hospital and Mercy Medical Center affiliated to create Affinity Health System, Inc., strategic planning and a solid marketing plan carefully executed were instrumental in its success. A corporate identity campaign and product line identification were follow-up phases to the merger approval.

  6. Experimental and analytical studies of passive shutdown heat removal systems

    SciTech Connect

    Pedersen, D.; Tessier, J.; Heineman, J.; Stewart, R.; Anderson, T.; August, C.; Chawla, T.; Cheung, F.B.; Despe, O.; Haupt, H.J.

    1987-01-01

    Using a naturally circulating air stream to remove shutdown decay heat from a nuclear reactor vessel is a key feature of advanced liquid metal reactor (LMR) concepts developed by potential vendors selected by the Department of Energy. General Electric and Rockwell International continue to develop innovative design concepts aimed at improving safety, lowering plant costs, simplifying plant operation, reducing construction times, and most of all, enhancing plant licensability. The reactor program at Argonne National Laboratory (ANL) provides technical support to both organizations. The method of shutdown heat removal proposed employs a totally passive cooling system that rejects heat from the reactor by radiation and natural convection to air. The system is inherently reliable since it is not subject failure modes associated with active decay cooling systems. The system is designed to assure adequate cooling of the reactor under abnormal operating conditions associated with loss of heat removal through other heat transport paths.

  7. Osmoprotectants in Halomonas elongata: high-affinity betaine transport system and choline-betaine pathway.

    PubMed Central

    Cánovas, D; Vargas, C; Csonka, L N; Ventosa, A; Nieto, J J

    1996-01-01

    The osmoregulatory pathways of the moderately halophilic bacterium Halomonas elongata DSM 3043 have been investigated. This strain grew optimally at 1.5 to 2 M NaCl in M63 glucose-defined medium. It required at least 0.5 M NaCl for growth, which is a higher concentration than that exhibited by the H. elongata type strain ATCC 33173. Externally provided betaine, choline, or choline-O-sulfate (but not proline, ectoine, or proline betaine) enhanced the growth of H. elongata on 3 M NaCl-glucose-M63 plates, demonstrating the utilization of these compounds as osmoprotectants. Moreover, betaine and choline stimulated the growth of H. elongata DSM 3043 over the entire range of salinity, although betaine was more effective than choline at salinities below and above the optimum. We found that H. elongata DSM 3043 has at least one high-affinity transport system for betaine (K(m) = 3.06 microM and Vmax = 9.96 nmol of betaine min(-1) mg of protein(-1)). Competition assays demonstrated that proline betaine and ectoine, but not proline, choline, or choline-O-sulfate, are also transported by the betaine permease. Finally, thin-layer chromatography and 13C-nuclear magnetic resonance analysis showed that exogenous choline was taken up and transformed to betaine by H. elongata, demonstrating the existence of a choline-glycine betaine pathway in this moderately halophilic bacterium. PMID:8955405

  8. Partial purification of the 5-hydroxytryptophan-reuptake system from human blood platelets using a citalopram-derived affinity resin

    SciTech Connect

    Biessen, E.A.L; Horn, A.S.; Robillard, G.T. )

    1990-04-03

    This paper describes a procedure for the synthesis and application of a citalopram-derived affinity resin in purifying the 5HT-reuptake system from human blood platelets. A two-step scheme has been developed for partial purification, based on wheat germ agglutinin-lectin (WGA) affinity and citalopram affinity chromatographies. Upon solubilization of the carrier with 1% digitonin, a 50-70-fold increase in specific ({sup 3}H) imipramine binding activity with a 70% recovery could be accomplished through WGA-lectin chromatography. The WGA pool was then subjected to affinity chromatography on citalopram-agarose. At least 90% of the binding capacity adsorbed to the column. Specific elution using 10 {mu}M citalopram resulted in a 22% recovery of binding activity. A 10,000-fold overall purification was obtained by using this two-step procedure. Analysis of the fractions on SDS-PAGE after {sup 125}I labeling revealed specific elution of 78- and 55-kDa proteins concomitant with the appearance of ({sup 3}H) imipramine binding activity. The pharmacological profile of the partially purified reuptake system correlated well with that derived from the crude membrane-bound reuptake system, suggesting a copurification of the 5HT binding activity and ({sup 3}H)imipramine binding activity.

  9. Determination of the kinetic rate constant of cyclodextrin supramolecular systems by high performance affinity chromatography.

    PubMed

    Li, Haiyan; Ge, Jingwen; Guo, Tao; Yang, Shuo; He, Zhonggui; York, Peter; Sun, Lixin; Xu, Xu; Zhang, Jiwen

    2013-08-30

    It is challenging and extremely difficult to measure the kinetics of supramolecular systems with extensive, weak binding (Ka<10(5)M(-1)), and fast dissociation, such as those composed of cyclodextrins and drugs. In this study, a modified peak profiling method based on high performance affinity chromatography (HPAC) was established to determine the dissociation rate constant of cyclodextrin supramolecular systems. The interactions of β-cyclodextrin with acetaminophen and sertraline were used to exemplify the method. The retention times, variances and the plate heights of the peaks for acetaminophen or sertraline, conventional non-retained substance (H2O) on the β-cyclodextrin bonded column and a control column were determined at four flow rates under linear elution conditions. Then, plate heights for the theoretical non-retained substance were estimated by the modified HPAC method, in consideration of the diffusion and stagnant mobile phase mass transfer. As a result, apparent dissociation rate constants of 1.82 (±0.01)s(-1) and 3.55 (±0.37)s(-1) were estimated for acetaminophen and sertraline respectively at pH 6.8 and 25°C with multiple flow rates. Following subtraction of the non-specific binding with the support, dissociation rate constants were estimated as 1.78 (±0.00) and 1.91 (±0.02)s(-1) for acetaminophen and sertraline, respectively. These results for acetaminophen and sertraline were in good agreement with the magnitude of the rate constants for other drugs determined by capillary electrophoresis reported in the literature and the peak fitting method we performed. The method described in this work is thought to be suitable for other supramolecules, with relatively weak, fast and extensive interactions.

  10. Elastomeric impression materials and cleaning systems for residue removal

    NASA Astrophysics Data System (ADS)

    Prochazka, T. M.

    1983-01-01

    A materials evaluation program was conducted to characterize castable resin compounds as suitable dimensional inspection aids. A fast curing dimethylsilicone based compound was selected as the best performer of the eleven compounds tested. Evaluation of physical properties revealed an inherent problem of particle adherence to metal surfaces tested. A cleaning study was conducted to determine the effectiveness of the solvent systems in removing particulate matter from test surfaces. Silicon residues which can adversely affect bonding characteristics of the metals were identified in cleaning study tests. One solvent system composed of alkylarylsulfonic acids, toluene, and dichloromethane, gave superior results in breaking down and removing these polymerized compounds.

  11. A low-cost affinity purification system using β-1,3-glucan recognition protein and curdlan beads.

    PubMed

    Horiuchi, Masataka; Takahasi, Kiyohiro; Kobashigawa, Yoshihiro; Ochiai, Masanori; Inagaki, Fuyuhiko

    2012-08-01

    Silkworm β-1,3-glucan recognition protein (βGRP) tightly and specifically associates with β-1,3-glucan. We report here an affinity purification system named the 'GRP system', which uses the association between the β-1,3-glucan recognition domain of βGRP (GRP-tag), as an affinity tag, and curdlan beads. Curdlan is a water-insoluble β-1,3-glucan reagent, the low cost of which (about 100 JPY/g) allows the economical preparation of beads. Curdlan beads can be readily prepared by solubilization in an alkaline solution, followed by neutralization, sonication and centrifugation. We applied the GRP system to preparation of several proteins and revealed that the expression levels of the GRP-tagged proteins in soluble fractions were two or three times higher than those of the glutathione S-transferase (GST)-tagged proteins. The purity of the GRP-tagged proteins on the curdlan beads was comparable to that of the GST-tagged proteins on glutathione beads. The chemical stability of the GRP system was more robust than conventional affinity systems under various conditions, including low pH (4-6). Biochemical and structural analyses revealed that proteins produced using the GRP system were structurally and functionally active. Thus, the GRP system is suitable for both the large- and small-scale preparation of recombinant proteins for functional and structural analyses.

  12. Removal of humic and tannic acids by adsorption-coagulation combined systems with activated biochar.

    PubMed

    Jung, Chanil; Phal, Narong; Oh, Jeill; Chu, Kyoung Hoon; Jang, Min; Yoon, Yeomin

    2015-12-30

    Despite recent interest in transforming biomass into bio-oil and syngas, there is inadequate information on the compatibility of byproducts (e.g., biochar) with agriculture and water purification infrastructures. A pyrolysis at 300°C yields efficient production of biochar, and its physicochemical properties can be improved by chemical activation, resulting in a suitable adsorbent for the removal of natural organic matter (NOM), including hydrophobic and hydrophilic substances, such as humic acids (HA) and tannic acids (TA), respectively. In this study, the adsorption affinities of different HA and TA combinations in NOM solutions were evaluated, and higher adsorption affinity of TA onto activated biochar (AB) produced in the laboratory was observed due to its superior chemisorption tendencies and size-exclusion effects compared with that of HA, whereas hydrophobic interactions between adsorbent and adsorbate were deficient. Assessment of the AB role in an adsorption-coagulation hybrid system as nuclei for coagulation in the presence of aluminum sulfate (alum) showed a synergistic effect in a HA-dominated NOM solution. An AB-alum hybrid system with a high proportion of HA in the NOM solution may be applicable as an end-of-pipe solution.

  13. Designing Bioretention Systems to Improve Nitrogen Removal - poster

    EPA Science Inventory

    Rain gardens, also referred to as bioretention systems, are designed primarily to infiltrate stormwater flow and reduce surface runoff and peak flows to receiving streams. Additionally, they are known to remove stressors from urban stormwater runoff, including oil and grease, pho...

  14. Crewmember repairing the Regenerative Carbon Dioxide Removal System wiring.

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Mission Pilot Ken Bowersox, busy at work on the wiring harness for the Regenerative Carbon Dioxide Removal System located under the mid deck floor. Photo shows Bowersox splicing wires together to 'fool' a faulty sensor that caused the 'air conditioner' to shut down.

  15. BOA: Pipe-asbestos insulation removal robot system

    SciTech Connect

    Schempf, H.; Bares, J.; Mutschler, E.

    1995-12-31

    This paper describes the BOA system, a mobile pipe-external crawler used to remotely strip and bag (possibly contaminated) asbestos-containing lagging and insulation materials (ACLIM) from various diameter pipes in (primarily) industrial installations across the DOE weapons complex. The mechanical removal of ACLIM is very cost-effective due to the relatively low productivity and high cost involved in human removal scenarios. BOA, a mechanical system capable of removing most forms of lagging (paper, plaster, aluminum sheet, clamps, screws and chicken-wire), and insulation (paper, tar, asbestos fiber, mag-block) uses a circular cutter and compression paddles to cut and strip the insulation off the pipe through compression, while a HEPA-filter and encapsulant system maintain a certifiable vacuum and moisture content inside the system and on the pipe, respectively. The crawler system has been built and is currently undergoing testing. Key design parameters and performance parameters are developed and used in performance testing. Since the current system is a testbed, we also discuss future enhancements and outline two deployment scenarios (robotic and manual) for the final system to be designed and completed by the end of FY `95. An on-site demonstration is currently planned for Fernald in Ohio and Oak Ridge in Tennessee.

  16. Characterization of the low affinity transport system for NO(3)(-) uptake by Citrus roots.

    PubMed

    Cerezo, M; Flors, V; Legaz, F; García-Agustín, P

    2000-12-07

    Three-month old citrange Troyer (hybrid of Citrus sinensis x Poncirus trifoliata) seedlings were grown hydroponically and, after a period of NO(3)(-) starvation, plants were transferred to solutions enriched with K(15)NO(3) (96% atoms 15N excess) to measure 15NO(3)(-) uptake rates as a function of external 15NO(3)(-) concentrations. Two different NO(3)(-) uptake systems were found. Between 1 and 50 mM 15NO(3)(-) in the uptake solution medium, the uptake rate increased linearly due to the low affinity transport system (LATS). Nitrate reductase activity showed the same response to external [NO(3)(-)], and also appears to be regulated by the rate of nitrate uptake. Nitrate pre-treatments had a represive effect on NO(3)(-) uptake rate measured at 5 or 30 mM external [15NO(3)(-)]. The extent of the inhibition depended on the [NO(3)(-)] during the pre-treatment and in the uptake solution. These results suggest that the LATS of Citrus seedlings is under feedback control by the N status of the plant. Accordingly, addition of amino acids (Glu, Asp, Asn, Gln) to the uptake solution resulted in a decrease in 15NO(3)(-) uptake rate. However, the inactivation of nitrate reductase activity after treatment of the seedlings with either 100 or 500 µM WO(4)(2-) did not affect the activity of the LATS. Metabolic uncouplers, 2,4-DNP and KCN, reduced the uptake rate by 43.3% and 41.4% respectively at 5mM external [15NO(3)(-)]. However, these compounds had little effect when 15NO(3)(-) uptake was assayed at 30 mM external concentration. The ATPase inhibitors DCCD and DES reduced 15NO(3)(-) uptake by 68.8%-35.6%, at both external [15NO(3)(-)]. Nitrate uptake by the LATS declined with the increase of the solution pH beyond pH 4. The data presented are discussed in the context of the kinetics, energy dependence and regulation of NO(3)(-) uptake.

  17. System for the removal of contaminant soil-gas vapors

    DOEpatents

    Weidner, J.R.; Downs, W.C.; Kaser, T.G.; Hall, H.J.

    1997-12-16

    A system extracts contaminated vapors from soil or other subsurface regions by using changes in barometric pressure to operate sensitive check valves that control air entry and removal from wells in the ground. The system creates an efficient subterranean flow of air through a contaminated soil plume and causes final extraction of the contaminants from the soil to ambient air above ground without any external energy sources. 4 figs.

  18. System for the removal of contaminant soil-gas vapors

    DOEpatents

    Weidner, Jerry R.; Downs, Wayne C.; Kaser, Timothy G.; Hall, H. James

    1997-01-01

    A system extracts contaminated vapors from soil or other subsurface regions by using changes in barometric pressure to operate sensitive check valves that control air entry and removal from wells in the ground. The system creates an efficient subterranean flow of air through a contaminated soil plume and causes final extraction of the contaminants from the soil to ambient air above ground without any external energy sources.

  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. AGIA Tag System Based on a High Affinity Rabbit Monoclonal Antibody against Human Dopamine Receptor D1 for Protein Analysis

    PubMed Central

    Yano, Tomoya; Takeda, Hiroyuki; Uematsu, Atsushi; Yamanaka, Satoshi; Nomura, Shunsuke; Nemoto, Keiichirou; Iwasaki, Takahiro; Takahashi, Hirotaka; Sawasaki, Tatsuya

    2016-01-01

    Polypeptide tag technology is widely used for protein detection and affinity purification. It consists of two fundamental elements: a peptide sequence and a binder which specifically binds to the peptide tag. In many tag systems, antibodies have been used as binder due to their high affinity and specificity. Recently, we obtained clone Ra48, a high-affinity rabbit monoclonal antibody (mAb) against dopamine receptor D1 (DRD1). Here, we report a novel tag system composed of Ra48 antibody and its epitope sequence. Using a deletion assay, we identified EEAAGIARP in the C-terminal region of DRD1 as the minimal epitope of Ra48 mAb, and we named this sequence the “AGIA” tag, based on its central sequence. The tag sequence does not include the four amino acids, Ser, Thr, Tyr, or Lys, which are susceptible to post-translational modification. We demonstrated performance of this new tag system in biochemical and cell biology applications. SPR analysis demonstrated that the affinity of the Ra48 mAb to the AGIA tag was 4.90 × 10−9 M. AGIA tag showed remarkably high sensitivity and specificity in immunoblotting. A number of AGIA-fused proteins overexpressed in animal and plant cells were detected by anti-AGIA antibody in immunoblotting and immunostaining with low background, and were immunoprecipitated efficiently. Furthermore, a single amino acid substitution of the second Glu to Asp (AGIA/E2D) enabled competitive dissociation of AGIA/E2D-tagged protein by adding wild-type AGIA peptide. It enabled one-step purification of AGIA/E2D-tagged recombinant proteins by peptide competition under physiological conditions. The sensitivity and specificity of the AGIA system makes it suitable for use in multiple methods for protein analysis. PMID:27271343

  2. Minimization of the root of a quadratic functional under a system of affine equality constraints with application to portfolio management

    NASA Astrophysics Data System (ADS)

    Landsman, Zinoviy

    2008-10-01

    We present an explicit closed form solution of the problem of minimizing the root of a quadratic functional subject to a system of affine constraints. The result generalizes Z. Landsman, Minimization of the root of a quadratic functional under an affine equality constraint, J. Comput. Appl. Math. 2007, to appear, see , articles in press, where the optimization problem was solved under only one linear constraint. This is of interest for solving significant problems pertaining to financial economics as well as some classes of feasibility and optimization problems which frequently occur in tomography and other fields. The results are illustrated in the problem of optimal portfolio selection and the particular case when the expected return of finance portfolio is certain is discussed.

  3. An affinity-structure database of helix-turn-helix: DNA complexes with a universal coordinate system

    DOE PAGES

    AlQuraishi, Mohammed; Tang, Shengdong; Xia, Xide

    2015-11-19

    Molecular interactions between proteins and DNA molecules underlie many cellular processes, including transcriptional regulation, chromosome replication, and nucleosome positioning. Computational analyses of protein-DNA interactions rely on experimental data characterizing known protein-DNA interactions structurally and biochemically. While many databases exist that contain either structural or biochemical data, few integrate these two data sources in a unified fashion. Such integration is becoming increasingly critical with the rapid growth of structural and biochemical data, and the emergence of algorithms that rely on the synthesis of multiple data types to derive computational models of molecular interactions. We have developed an integrated affinity-structure database inmore » which the experimental and quantitative DNA binding affinities of helix-turn-helix proteins are mapped onto the crystal structures of the corresponding protein-DNA complexes. This database provides access to: (i) protein-DNA structures, (ii) quantitative summaries of protein-DNA binding affinities using position weight matrices, and (iii) raw experimental data of protein-DNA binding instances. Critically, this database establishes a correspondence between experimental structural data and quantitative binding affinity data at the single basepair level. Furthermore, we present a novel alignment algorithm that structurally aligns the protein-DNA complexes in the database and creates a unified residue-level coordinate system for comparing the physico-chemical environments at the interface between complexes. Using this unified coordinate system, we compute the statistics of atomic interactions at the protein-DNA interface of helix-turn-helix proteins. We provide an interactive website for visualization, querying, and analyzing this database, and a downloadable version to facilitate programmatic analysis. Lastly, this database will facilitate the analysis of protein-DNA interactions and the

  4. An affinity-structure database of helix-turn-helix: DNA complexes with a universal coordinate system

    SciTech Connect

    AlQuraishi, Mohammed; Tang, Shengdong; Xia, Xide

    2015-11-19

    Molecular interactions between proteins and DNA molecules underlie many cellular processes, including transcriptional regulation, chromosome replication, and nucleosome positioning. Computational analyses of protein-DNA interactions rely on experimental data characterizing known protein-DNA interactions structurally and biochemically. While many databases exist that contain either structural or biochemical data, few integrate these two data sources in a unified fashion. Such integration is becoming increasingly critical with the rapid growth of structural and biochemical data, and the emergence of algorithms that rely on the synthesis of multiple data types to derive computational models of molecular interactions. We have developed an integrated affinity-structure database in which the experimental and quantitative DNA binding affinities of helix-turn-helix proteins are mapped onto the crystal structures of the corresponding protein-DNA complexes. This database provides access to: (i) protein-DNA structures, (ii) quantitative summaries of protein-DNA binding affinities using position weight matrices, and (iii) raw experimental data of protein-DNA binding instances. Critically, this database establishes a correspondence between experimental structural data and quantitative binding affinity data at the single basepair level. Furthermore, we present a novel alignment algorithm that structurally aligns the protein-DNA complexes in the database and creates a unified residue-level coordinate system for comparing the physico-chemical environments at the interface between complexes. Using this unified coordinate system, we compute the statistics of atomic interactions at the protein-DNA interface of helix-turn-helix proteins. We provide an interactive website for visualization, querying, and analyzing this database, and a downloadable version to facilitate programmatic analysis. Lastly, this database will facilitate the analysis of protein-DNA interactions and the

  5. Removal of Cryptosporidium parvum in bank filtration systems

    NASA Astrophysics Data System (ADS)

    Harter, T.; Atwill, E. R.; Hou, L. L.

    2003-04-01

    The protozoan pathogen Cryptosporidium parvum is a leading cause of waterborne disease. Many surface water systems therefore depend on filtration systems, including bank filtration systems, for the removal of the pathogenic oocysts. To better understand the effectiveness, e.g., of bank filtration systems, we have implemented a series of columns studies under various environmental conditions (column length: 10 cm - 60 cm, flow rates: 0.7 m/d - 30 m/d, ionic strength: 0.01 - 100 mM, filter grain size: 0.2 - 2 mm, various solution chemistry). We show that classic colloid filtration theory is a reasonable tool for predicting the initial breakthrough of C. parvum in pulsed injections of the oocyst through sand columns, although the model does not account for the significant tailing that occurs in C. parvum transport. Application of colloid filtration theory to bank filtration system is further limited by the intrinsic heterogeneity of the geologic systems used for bank filtration. We couple filtration theory with a stochastic subsurface transport approach and with percolation theory to account for the effects of intrinsic heterogeneity. We find that a 1-log removal can be achieved even under relatively adverse conditions (low collision efficiency, high velocity) if 85% - 90% of the sedimentary hydrofacies located within the bank filtration system or of the coarsest known hydrofacies connecting the riverbed with the extraction system has a grain-size distribution with a 10% passing diameter equal to 1 mm. One millimeter is a standard sieve size in sediment analysis.

  6. Benzene removal by PAC in jet flocculation system

    SciTech Connect

    Sobrinho, J.A.H.; Thiem, L.T.; Alkhatib, E.A.

    1997-10-01

    A jet flocculator/powdered activated carbon (PAC) adsorption pilot plant was designed, built, and operated in order to evaluate a water treatment process capable of simultaneous adsorption of benzene and flocculation of PAC and silica clay particles. The jet flocculation/PAC system successfully combined, in the same reactor, flocculation of suspended solids by using jet mixing, solids retention using pall rings, and benzene removal by PAC adsorption. The advantages of this process included operational simplicity, reliability, and low energy consumption. The jet flocculator/PAC adsorption system was able to achieve suspended solids and benzene removals of approximately 80 and 95%, respectively, from an influent containing 70 mg/L of suspended solids (silica clay and PAC) and 100 {micro}g/L of benzene.

  7. Optimization of contaminant removal for heterogeneous systems by soil venting

    SciTech Connect

    Walton, J.C.; Casey, D.; Anker, C.; LeMone, D.

    1996-12-31

    The efficiency of remediation of vadose zone organic compounds can be enhanced by refinement of methods for soil venting and bioventing in complex heterogeneous systems. This can be accomplished by (a) identification of physical and chemical conditions (e.g., soil temperature, moisture content, flow rates) required for rapid contaminant removal rates, (b) precise engineering control of identified parameters in the subsurface, and (c) development of knowledge-based operational strategies providing greater removal efficiencies at low cost. One method with promise is to moderately heat and humidify the input/replacement air during venting. Initial calculations indicate that this strategy may be quite effective in enhancing remediation of heterogeneous systems with diffusional control of cleanup time.

  8. Probing the influence of anomeric effects on the lithium ion affinity in 1,3-diaza systems: a computational study.

    PubMed

    Kesharwani, Manoj K; Thiel, Walter; Ganguly, Bishwajit

    2010-10-07

    Lithium ion affinities of methanediamine (MDA), N,N,N',N'-tetramethylmethanediamine (TMMDA), 1,3-diazacyclohexane (DAC), trans-3,5-diazabicyclo[4.4.0]decane (trans-3,5-DBD), trans-1,3-diazabicyclo[4.4.0]decane (trans-1,3-DBD), cis-1,3-diazabicyclo[4.4.0]decane (cis-1,3-DBD), 1,5-diazabicyclo[3.3.1]nonane (DBN), trans-decahydro-8a,9a-diazaanthracene (trans-DDA), cis-decahydro-8a,9a-diazaanthracene (cis-DDA), 1,3-diazetidine (DAT), 1,3-imidazolidine (IMD), and 1,3-diazepane (DAP) have been studied by using density functional theory (DFT) and correlated ab initio methods. Possible conformers of these compounds were optimized at the B3LYP/6-31+G* level, and relative energies were evaluated at the MP2/6-311+G**//B3LYP/6-31+G* level. The experimental lithium ion affinities for reference molecules (i.e., ammonia and trimethylamine) are well-reproduced at these levels of theory. NBO analysis shows the influence of anomeric effects (n(N) → σ*(C-N) hyperconjugative interactions) on the conformational stability of the title compounds; however, the electrostatic and steric contributions included in the NBO Lewis term also affect the stabilities in some cases. The influence of anomeric effect is apparent in cis-DDA, where the nitrogen involved in n(N) → σ*(C-N) hyperconjugative interaction (cis-DDA-Li2) has a lithium ion affinity 1.7 kcal/mol lower than the nitrogen not involved in n(N) → σ*(C-N) hyperconjugative interaction (cis-DDA-Li1). In general, the computed lithium ion affinities were found to be conformationally dependent. The NBO results showed that the lithium ion affinities are also governed by the interplay of n(N) → σ*(C-N) hyperconjugative interactions and the steric strain caused upon lithiation. Further, the ring size also influences the lithium ion affinities in the 1,3-diaza monocyclic systems. In some complexes multiple coordination of the lithium ion is possible by inversion of one of the nitrogen atoms.

  9. Removable, hermetically-sealing, filter attachment system for hostile environments

    DOEpatents

    Mayfield, Glenn L [Richland, WA

    1983-01-01

    A removable and reusable filter attachment system. A filter medium is fixed o, and surrounded by, a filter frame having a coaxial, longitudinally extending, annular rim. The rim engages an annular groove which surrounds the opening of a filter housing. The annular groove contains a fusible material and a heating mechanism for melting the fusible material. Upon resolidifying, the fusible material forms a hermetic bond with the rim and groove. Remelting allows detachment and replacement of the filter frame.

  10. BOA II: pipe-asbestos insulation removal system

    SciTech Connect

    Schempf, H.; Mutschler; Boehmke, S.; Chemel, B.; Piepgras, C.

    1996-12-31

    BOA system is a mobile pipe-external robotic crawler used to remotely strip and bag asbestos-containing lagging and insulation materials from various diameter pipes in (primarily) industrial installations. Steam and process lines within the DOE weapons complex warrant the use of a remote device due to high labor costs and high level of radioactive contamination, making manual removal costly and inefficient. Currently targeted facilities for demonstration and remediation are Fernald in Ohio and Oak Ridge in Tennessee.

  11. Reversing the antilock braking system theory for suture removal.

    PubMed

    Mangus, D J

    1987-06-01

    A simple and extremely practical technique for removal of long subcuticular sutures is possible by simply interposing a rubber band between the suture and the traction source. We have likened the technique in a reverse manner to the pulsing application of brakes in the antilock braking system now commonly found in modern automobiles. We also suggest with this paper that Prolene at this time be tried as the suture of choice in pullout repairs of all types.

  12. Pentek metal coating removal system: Baseline report; Summary

    SciTech Connect

    1997-07-31

    The Pentek metal coating removal system consists of the ROTO-PEEN Scaler, CORNER-CUTTER(R), and VAC-PAC(R). The system is designed to remove coatings from steel, concrete, brick, and wood. The Scaler uses 3M ROTO-PEEN tungsten carbide cutters, while the CORNER-CUTTER(R) uses solid needles for descaling activities. These are used with the VAC-PAC(R) vacuum system to capture dust and debris as removal of the coating takes place. The safety and health evaluation during the testing demonstration focused on two main areas of exposure: dust and noise. Dust exposure was minimal, but noise exposure was significant. Further testing for each exposure is recommended, since the outdoor environment where the testing demonstration took place may skew the results. It is feasible that dust and noise levels will be higher in an enclosed operating environment. Other areas of concern found were arm-hand vibration, whole-body vibration, ergonomics, heat stress, tripping hazards, electrical hazards, machine guarding, and lockout/tagout.

  13. Microbial Removals by a Novel Biofilter Water Treatment System

    PubMed Central

    Wendt, Christopher; Ives, Rebecca; Hoyt, Anne L.; Conrad, Ken E.; Longstaff, Stephanie; Kuennen, Roy W.; Rose, Joan B.

    2015-01-01

    Two point-of-use drinking water treatment systems designed using a carbon filter and foam material as a possible alternative to traditional biosand systems were evaluated for removal of bacteria, protozoa, and viruses. Two configurations were tested: the foam material was positioned vertically around the carbon filter in the sleeve unit or horizontally in the disk unit. The filtration systems were challenged with Cryptosporidium parvum, Raoultella terrigena, and bacteriophages P22 and MS2 before and after biofilm development to determine average log reduction (ALR) for each organism and the role of the biofilm. There was no significant difference in performance between the two designs, and both designs showed significant levels of removal (at least 4 log10 reduction in viruses, 6 log10 for protozoa, and 8 log10 for bacteria). Removal levels meet or exceeded Environmental Protection Agency (EPA) standards for microbial purifiers. Exploratory test results suggested that mature biofilm formation contributed 1–2 log10 reductions. Future work is recommended to determine field viability. PMID:25758649

  14. Space debris removal system using a small satellite

    NASA Astrophysics Data System (ADS)

    Nishida, Shin-Ichiro; Kawamoto, Satomi; Okawa, Yasushi; Terui, Fuyuto; Kitamura, Shoji

    2009-07-01

    Since the number of satellites in Earth orbit is steadily increasing, space debris will eventually pose a serious problem to near-Earth space activities if left unchecked, and so effective measures to mitigate it are becoming urgent. Equipping new satellites with an end-of-life de-orbit or orbital lifetime reduction capability could be an effective means of reducing the amount of debris by reducing the probability of the collisions between objects. On the other hand, the active removal of space debris and the retrieval of failed satellites by spacecraft are other possible measures. The Institute of Aerospace Technology, Japan Aerospace Exploration Agency (JAXA), is studying a micro-satellite system for active space debris removal, and is examining the applicability of electro-dynamic tether (EDT) technology as its high efficiency orbital transfer system. A small EDT package provides a possible means for lowering the orbits of objects without the need for propellant. Capture is indispensable for the retrieval of large space debris objects, and we propose a flexible robot arm for this purpose. This paper discusses a space debris removal satellite system and describes the development status of prototypes of the EDT package and a new robot arm for capturing non-cooperative targets.

  15. System for fuel rod removal from a reactor module

    DOEpatents

    Matchett, R.L.; Fodor, G.; Kikta, T.J.; Bacvinsicas, W.S.; Roof, D.R.; Nilsen, R.J.; Wilczynski, R.

    1988-07-28

    A robotic system for remote underwater withdrawal of the fuel rods from fuel modules of a light water breeder reactor includes a collet/grapple assembly for gripping and removing fuel rods in each module, which is positioned by use of a winch and a radial support means attached to a vertical support tube which is mounted over the fuel module. A programmable logic controller in conjunction with a microcomputer, provides control for the accurate positioning and pulling force of the rod grapple assembly. Closed circuit television cameras are provided which aid in operator interface with the robotic system. 7 figs.

  16. System for fuel rod removal from a reactor module

    DOEpatents

    Matchett, Richard L.; Roof, David R.; Kikta, Thomas J.; Wilczynski, Rosemarie; Nilsen, Roy J.; Bacvinskas, William S.; Fodor, George

    1990-01-01

    A robotic system for remote underwater withdrawal of the fuel rods from fuel modules of a light water breeder reactor includes a collet/grapple assembly for gripping and removing fuel rods in each module, which is positioned by use of a winch and a radial support means attached to a vertical support tube which is mounted over the fuel module. A programmable logic controller in conjunction with a microcomputer, provides control for the accurate positioning and pulling force of the rod grapple assembly. Closed circuit television cameras are provided which aid in operator interface with the robotic system.

  17. System Study: Residual Heat Removal 1998–2013

    SciTech Connect

    Schroeder, John Alton

    2015-02-01

    This report presents an unreliability evaluation of the residual heat removal (RHR) system in two modes of operation (low-pressure injection in response to a large loss-of-coolant accident and post-trip shutdown-cooling) at 104 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2013 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10-year period while yearly estimates for system unreliability are provided for the entire active period. No statistically significant trends were identified in the RHR results.

  18. Emergency heat removal system for a nuclear reactor

    DOEpatents

    Dunckel, Thomas L.

    1976-01-01

    A heat removal system for nuclear reactors serving as a supplement to an Emergency Core Cooling System (ECCS) during a Loss of Coolant Accident (LOCA) comprises a plurality of heat pipes having one end in heat transfer relationship with either the reactor pressure vessel, the core support grid structure or other in-core components and the opposite end located in heat transfer relationship with a heat exchanger having heat transfer fluid therein. The heat exchanger is located external to the pressure vessel whereby excessive core heat is transferred from the above reactor components and dissipated within the heat exchanger fluid.

  19. Satellite refrigerator compressors with the oil and moisture removal systems

    SciTech Connect

    Satti, J.A.

    1983-08-01

    There are twenty-eight compressors installed around the Main Accelerator Ring in seven locations. Drawing 9140-ME-129720 shows the piping and the components schematic for four Mycom compressor skids per building with each having an independent oil and moisture removal system. The Mycom skids each consist of an oil injected screw compressor of 750 SCFM capacity with a 350 hp motor, oil pump, oil cooler, and oil separator. Helium gas returning from the heat exchanger train is compressed from 1 atm to 20 atm in the compressor. The compressed gas is then passed through the three coalescer de-mister where oil mist is separated from the helium gas. The helium gas then flows through the charcoal adsorber and molecular sieve where any residual oil vapor and water vapor are removed. The final stage of purification is the final filter which removes any remaining particulates from the compressed helium gas. The end product of this system is compressed and purified helium gas ready to be cooled down to cryogenic temperatures.

  20. One active debris removal control system design and error analysis

    NASA Astrophysics Data System (ADS)

    Wang, Weilin; Chen, Lei; Li, Kebo; Lei, Yongjun

    2016-11-01

    The increasing expansion of debris presents a significant challenge to space safety and sustainability. To address it, active debris removal, usually involving a chaser performing autonomous rendezvous with targeted debris to be removed is a feasible solution. In this paper, we explore a mid-range autonomous rendezvous control system based on augmented proportional navigation (APN), establishing a three-dimensional kinematic equation set constructed in a rotating coordinate system. In APN, feedback control is applied in the direction of line of sight (LOS), thus analytical solutions of LOS rate and relative motion are expectedly obtained. To evaluate the effectiveness of the control system, we adopt Zero-Effort-Miss (ZEM) in this research as the index, the uncertainty of which is directly determined by that of LOS rate. Accordingly, we apply covariance analysis (CA) method to analyze the propagation of LOS rate uncertainty. Consequently, we find that the accuracy of the control system can be verified even with uncertainty and the CA method is drastically more computationally efficient compared with nonlinear Monte-Carlo method. Additionally, to justify the superiority of the system, we further discuss more simulation cases to show the robustness and feasibility of APN proposed in the paper.

  1. BOA: Asbestos pipe insulation removal robot system. Phase 1

    SciTech Connect

    Schempf, H.; Bares, J.E.

    1995-02-01

    The project described in this report targets the development of a mechanized system for safe, cost-efficient and automated abatement of asbestos containing materials used as pipe insulation. Based on several key design criteria and site visits, a proof-of-concept prototype robot system, dubbed BOA, was designed and built, which automatically strips the lagging and insulation from the pipes, and encapsulates them under complete vacuum operation. The system can operate on straight runs of piping in horizontal or vertical orientations. Currently we are limited to four-inch diameter piping without obstacles as well as a somewhat laborious emplacement and removal procedure -- restrictions to be alleviated through continued development. BOA removed asbestos at a rate of 4-5 ft./h compared to 3 ft./h for manual removal of asbestos with a 3-person crew. The containment and vacuum system on BOA was able to achieve the regulatory requirement for airborne fiber emissions of 0.01 fibers/ccm/ 8-hr. shift. This program consists of two phases. The first phase was completed and a demonstration was given to a review panel, consisting of DOE headquarters and site representatives as well as commercial abatement industry representatives. Based on the technical and programmatic recommendations drafted, presented and discussed during the review meeting, a new plan for the Phase II effort of this project was developed. Phase 11 will consist of a 26-month effort, with an up-front 4-month site-, market-, cost/benefit and regulatory study before the next BOA robot (14 months) is built, and then deployed and demonstrated (3 months) at a DOE site (such as Fernald or Oak Ridge) by the beginning of FY`97.

  2. Sequential peptide affinity purification system for the systematic isolation and identification of protein complexes from Escherichia coli.

    PubMed

    Babu, Mohan; Butland, Gareth; Pogoutse, Oxana; Li, Joyce; Greenblatt, Jack F; Emili, Andrew

    2009-01-01

    Biochemical purification of affinity-tagged proteins in combination with mass spectrometry methods is increasingly seen as a cornerstone of systems biology, as it allows for the systematic genome-scale characterization of macromolecular protein complexes, representing demarcated sets of stably interacting protein partners. Accurate and sensitive identification of both the specific and shared polypeptide components of distinct complexes requires purification to near homogeneity. To this end, a sequential peptide affinity (SPA) purification system was developed to enable the rapid and efficient isolation of native Escherichia coli protein complexes (J Proteome Res 3:463-468, 2004). SPA purification makes use of a dual-affinity tag, consisting of three modified FLAG sequences (3X FLAG) and a calmodulin binding peptide (CBP), spaced by a cleavage site for tobacco etch virus (TEV) protease (J Proteome Res 3:463-468, 2004). Using the lambda-phage Red homologous recombination system (PNAS 97:5978-5983, 2000), a DNA cassette, encoding the SPA-tag and a selectable marker flanked by gene-specific targeting sequences, is introduced into a selected locus in the E. coli chromosome so as to create a C-terminal fusion with the protein of interest. This procedure aims for near-endogenous levels of tagged protein production in the recombinant bacteria to avoid spurious, non-specific protein associations (J Proteome Res 3:463-468, 2004). In this chapter, we describe a detailed, optimized protocol for the tagging, purification, and subsequent mass spectrometry-based identification of the subunits of even low-abundance bacterial protein complexes isolated as part of an ongoing large-scale proteomic study in E. coli (Nature 433:531-537, 2005).

  3. Final design of a space debris removal system

    NASA Technical Reports Server (NTRS)

    Carlson, Erika; Casali, Steve; Chambers, Don; Geissler, Garner; Lalich, Andrew; Leipold, Manfred; Mach, Richard; Parry, John; Weems, Foley

    1990-01-01

    The objective is the removal of medium sized orbital debris in low Earth orbits. The design incorporates a transfer vehicle and a netting vehicle to capture the medium size debris. The system is based near an operational space station located at 28.5 degrees inclination and 400 km altitude. The system uses ground based tracking to determine the location of a satellite breakup or debris cloud. This data is unloaded to the transfer vehicle, and the transfer vehicle proceeds to rendezvous with the debris at a lower altitude parking orbit. Next, the netting vehicle is deployed, tracks the targeted debris, and captures it. After expending the available nets, the netting vehicle returns to the transfer vehicle for a new netting module and continues to capture more debris in the target area. Once all the netting modules are expended, the transfer vehicle returns to the space station's orbit, where it is resupplied with new netting modules from a space shuttle load. The new modules are launched by the shuttle from the ground, and the expended modules are taken back to Earth for removal of the captured debris, refueling, and repacking of the nets. Once the netting modules are refurbished, they are taken back into orbit for reuse. In a typical mission, the system has the ability to capture 50 pieces of orbital debris. One mission will take about six months. The system is designed to allow for a 30 degree inclination change on the outgoing and incoming trips of the transfer vehicle.

  4. VecLoader HEPA Vacuum Insulation Removal System

    SciTech Connect

    None, None

    1999-09-01

    The United States Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the deactivation and decommissioning (D&D) of nuclear facilities. To this end, the Deactivation and Decommissioning Focus Area (DDFA) of the DOE’s Office of Science and Technology sponsors Large-Scale Demonstration Projects (LSDPs) at which developers and vendors of improved or innovative technologies showcase products that are potentially beneficial to DOE’s projects and to others in the D&D community. Benefits sought include decreased health and safety risks to personnel and the environment, increased productivity, decreased costs and shortened schedules. The U.S. Department of Energy (DOE) Fernald Environmental Management Project’s (FEMP’s) Decontamination and Decommissioning (D&D) Plan requires that interior and exterior walls of buildings that are being demolished be disassembled and all insulating materials removed prior to demolition. This report provides a comparative analysis of the baseline manual insulation removal technique currently employed at the FEMP, with an innovative vacuum insulation removal system.

  5. Ornamental plants for micropollutant removal in wetland systems.

    PubMed

    Macci, Cristina; Peruzzi, Eleonora; Doni, Serena; Iannelli, Renato; Masciandaro, Grazia

    2015-02-01

    The objective of this paper was to evaluate the efficiency of micropollutant removal, such as Cu, Zn, carbamazepine, and linear alkylbenzene sulfonates (LAS), through the use of a subsurface vertical flow constructed wetland system with ornamental plants. Zantedeschia aethiopica, Canna indica, Carex hirta, Miscanthus sinensis, and Phragmites australis were selected and planted in lysimeters filled up with gravel. The lysimeters were completely saturated with synthetic wastewater (N 280 mg L(-1), P 30 mg L(-1), Cu 3.6 mg L(-1), Zn 9 mg L(-1), carbamazepine 5 μg L(-1), linear alkylbenzene sulfonates 14 mg L(-1)), and the leaching water was collected for analysis after 15, 30, and 60 days in winter-spring and spring-summer periods. Nutrients (N and P) and heavy metals decreased greatly due to both plant activity and adsorption. C. indica and P. australis showed the highest metal content in their tissues and also the greatest carbamazepine and LAS removal. In these plants, the adsorption/degradation processes led to particularly high oxidative stress, as evidenced by the significantly high levels of ascorbate peroxidase activity detected. Conversely, Z. aethiopica was the less efficient plant in metal and organic compound removal and was also less stressed in terms of ascorbate peroxidase activity.

  6. [Analysis of rice leaves proteomes by liquid chromatography-tandem, mass spectrometry based on the purification using a novel affinity detergent removal spin column].

    PubMed

    Cao, Xiaolin; Gong, Jiadi; Chen, Mingxue; Yu, Shasha; Bian, Yingfang; Cao, Zhaoyun

    2014-11-01

    A purification method was established for the analysis of proteomes in rice leaves based on a novel detergent removal spin column (DRSC). The proteins were extracted by phenol protein extraction method followed by sodium dodecyl sulfate (SDS) lysis. The lysate was purified by the detergent removal spin column and the enzymolytic peptides were detected by the nanoflow liquid chromatography-hybrid linear trap quadrupole orbitrap mass spectrometry (nanoLC-LTQ/Orbitrap). In terms of SDS removal efficiencies and protein identification, the method of DRSC was compared with those of filter aided sample preparation (FASP) and acetone precipitation. As a result, there were good efficiencies ( > 95%) of SDS removal for the three methods. With the DRSC purification strategy, 563 proteins were identified from rice leaves, while only 196 and 306 proteins were identified by FASP and acetone precipitation procedures respectively, in spite of certain complementarities among these identified proteins by the three methods. DRSC is suitable for proteins with various relative molecular masses and pI values. However, there were similar losses of proteins with different relative molecular masses and pI values with the other two methods. Using the established method, 588 proteins were identified by once injection analysis. According to the molecular functions, 296 proteins with at least two identified peptides can be classified into eight categories with binding activity, enzyme activity, transporter activity, inhibitor activity, structural constitute, catalytic activity, other and unknown functions. The method provides technical reference for conducting rice proteomes.

  7. System and method for removal of buried objects

    DOEpatents

    Alexander, Robert G.; Crass, Dennis; Grams, William; Phillips, Steven J.; Riess, Mark

    2008-06-03

    The present invention is a system and method for removal of buried objects. According to one embodiment of the invention, a crane with a vibrator casing driver is used to lift and suspend a large diameter steel casing over the buried object. Then the casing is driven into the ground by the vibratory driver until the casing surrounds the buried object. Then the open bottom of the casing is sealed shut by injecting grout into the ground within the casing near its bottom. When the seal has cured and hardened, the top of the casing is lifted to retrieve the casing, with the buried object inside, from the ground.

  8. System, Apparatus, and Method for Active Debris Removal

    NASA Technical Reports Server (NTRS)

    Griffith, Sr., Anthony D. (Inventor); Kohli, Rajiv (Inventor); Burns, Susan H. (Inventor); Damico, Stephen J. (Inventor); Gruber, David J. (Inventor); Hickey, Christopher J. (Inventor); Lee, David E. (Inventor); Robinson, Travis M. (Inventor); Smith, Jason T. (Inventor); Spehar, Peter T. (Inventor)

    2017-01-01

    Systems, apparatuses, and methods for removal of orbital debris are provided. In one embodiment, an apparatus includes a spacecraft control unit configured to guide and navigate the apparatus to a target. The apparatus also includes a dynamic object characterization unit configured to characterize movement, and a capture feature, of the target. The apparatus further includes a capture and release unit configured to capture a target and deorbit or release the target. The collection of these apparatuses is then employed as multiple, independent and individually operated vehicles launched from a single launch vehicle for the purpose of disposing of multiple debris objects.

  9. BOA: Pipe-asbestos insulation removal robot system

    SciTech Connect

    Schempf, H.; Bares, J.; Schnorr, W.

    1995-10-01

    The BOA system is a mobile pipe-external robotic crawler used to remotely strip and bag asbestos-containing lagging and insulation materials (ACLIM) from various diameter pipes in (primarily) industrial installations. Steam and process lines within the DOE weapons complex warrant the use of a remote device due to the high labor costs and high level of radioactive contamination, making manual removal extremely costly and highly inefficient. Currently targeted facilities for demonstration and remediation are Fernald in Ohio and Oak Ridge in Tennessee.

  10. Closed-Loop System Removes Contaminants From Inert Gas

    NASA Technical Reports Server (NTRS)

    Sharma, Pramod K.

    1995-01-01

    Concentration of oxygen in this closed-loop system kept low by use of heated catalytic sorbent bed in cartridge. Proposed to keep concentration of water vapor low by use of predried zeolite sorbent bed in another cartridge, and to remove particles smaller than 0.1 micrometer by use of porous metal filters. In specific application, chamber is one in which semiconducting materials processed. By virtue of closed-loop operation, limited supply of inert gas adequate to provide atmosphere for industrial processing of semiconductors.

  11. Purification of papain by metal affinity partitioning in aqueous two-phase polyethylene glycol/sodium sulfate systems.

    PubMed

    Jiang, Zhi-Guo; Zhang, Hai-De; Wang, Wei-Tao

    2015-05-01

    A simple and inexpensive aqueous two-phase affinity partitioning system using metal ligands was introduced to improve the selectivity of commercial papain extraction. Polyethylene glycol 4000 was first activated using epichlorohydrin, then it was covalently linked to iminodiacetic acid. Finally, the specific metal ligand Cu(2+) was attached to the polyethylene glycol-iminodiacetic acid. The chelated Cu(2+) content was measured by atomic absorption spectrometry as 0.88 mol/mol (polyethylene glycol). The effects on the purification at different conditions, including polyethylene glycol molecular weight (2000, 4000, and 6000), concentration of phase-forming components (polyethylene glycol 12-20% w/w and sodium sulfate 12-20%, w/w), metal ligand type, and concentration, system pH and the commercial papain loading on papain extraction, were systematically studied. Under optimum conditions of the system, i.e. 18% w/w sodium sulfate, 18% w/w polyethylene glycol 4000, 1% w/w polyethylene glycol-iminodiacetic acid-Cu(2+) and pH 7, a maximum yield of 90.3% and a degree of purification of 3.6-fold were obtained. Compared to aqueous two phase extraction without ligands, affinity partitioning was found to be an effective technique for the purification of commercial papain with higher extraction efficiency and degree of purification.

  12. C-X...H contacts in biomolecular systems: how they contribute to protein-ligand binding affinity.

    PubMed

    Lu, Yunxiang; Wang, Yong; Xu, Zhijian; Yan, Xiuhua; Luo, Xiaoming; Jiang, Hualiang; Zhu, Weiliang

    2009-09-17

    The hydrogen bond acceptor capability of halogens has long been underappreciated in the field of biology. In this work, we have surveyed structures of protein complexes with halogenated ligands to characterize geometrical preferences of C-X...H contacts and contributions of such interactions to protein-ligand binding affinity. Notably, F...H interactions in biomolecules exhibit a remarkably different behavior as compared to three other kinds of X...H (X = Cl, Br, I) interactions, which has been rationalized by means of ab initio calculations using simple model systems. The C-X...H contacts in biological systems are characterized as weak hydrogen bonding interactions. Furthermore, the electrophile "head on" and nucleophile "side on" interactions of halogens have been extensively investigated through the examination of interactions in protein structures and a two-layer ONIOM-based QM/MM method. In biomolecular systems, C-X...H contacts are recognized as secondary interaction contributions to C-X...O halogen bonds that play important roles in conferring specificity and affinity for halogenated ligands. The results presented here are within the context of their potential applications in drug design, including relevance to the development of accurate force fields for halogens.

  13. Nitrogen removal using a vertically moving biofilm system.

    PubMed

    Rodgers, M; Burke, D

    2003-01-01

    The aim of this laboratory study was to establish the efficacy of a new experimental biofilm system for the removal of nitrogen from synthetic wastewater. The system consisted of six reactors in series: one anaerobic, one anoxic and four aerobic reactors. In both the anaerobic and anoxic reactors, a plastic cuboid module was repeatedly moved up and down in the wastewater, while being totally submerged at all times. In each of the aerobic reactors, an identical module to that used in the anaerobic and anoxic reactors was intermittently and repeatedly immersed in and lifted out of the wastewater. All the individual reactors had a bulk fluid volume of 28.2 litres and the average temperature of the wastewater was about 10 degrees C. Each module consisted of crossflow corrugated plastic sheets with a surface area of 1.824 m2. The nitrate recycle flow from the fourth aerobic tank to the anoxic tank was twice the inflow to that tank. In the anoxic reactor, filtered COD was removed at an average rate of 2.22 kg COD/m3 x d and nitrate-nitrogen was denitrified at a rate of 0.42 kg NO3-N/m3 x d. The average nitrification rate in the second aerobic reactor was 0.12 kg NH4-N/m3 x d. The new biofilm system was simple to construct and operate.

  14. ℒ1 adaptive controller for a class of non-affine multi-input multi-output nonlinear systems

    NASA Astrophysics Data System (ADS)

    Luo, Jie; Cao, Chengyu; Yang, Qinmin

    2013-02-01

    In this article, an extension of the ℒ1 adaptive control design is introduced for a class of non-affine Multi-Input Multi-Output nonlinear systems with unknown dynamics and unmeasured states. The system dynamics is represented in the normal form with the bounded-input-bounded-output internal dynamics. At first, a stable virtual reference counterpart is constructed. Thereafter, a piece-wise continuous adaptive law is introduced to the actual system along with a low-pass filtered control signal that allows for achieving arbitrarily close tracking of the input and the output signals of the reference system. Rigorous mathematical proof is provided, and the theoretical results are verified with the simulation.

  15. Conservation of `Moving' Energy in Nonholonomic Systems with Affine Constraints and Integrability of Spheres on Rotating Surfaces

    NASA Astrophysics Data System (ADS)

    Fassò, Francesco; Sansonetto, Nicola

    2016-04-01

    Energy is in general not conserved for mechanical nonholonomic systems with affine constraints. In this article we point out that, nevertheless, in certain cases, there is a modification of the energy that is conserved. Such a function is the pull-back of the energy of the system written in a system of time-dependent coordinates in which the constraint is linear, and for this reason will be called a `moving' energy. After giving sufficient conditions for the existence of a conserved, time-independent moving energy, we point out the role of symmetry in this mechanism. Lastly, we apply these ideas to prove that the motions of a heavy homogeneous solid sphere that rolls inside a convex surface of revolution in uniform rotation about its vertical figure axis, are (at least for certain parameter values and in open regions of the phase space) quasi-periodic on tori of dimension up to three.

  16. Process and system for removing impurities from a gas

    SciTech Connect

    Henningsen, Gunnar; Knowlton, Teddy Merrill; Findlay, John George; Schlather, Jerry Neal; Turk, Brian S

    2014-04-15

    A fluidized reactor system for removing impurities from a gas and an associated process are provided. The system includes a fluidized absorber for contacting a feed gas with a sorbent stream to reduce the impurity content of the feed gas; a fluidized solids regenerator for contacting an impurity loaded sorbent stream with a regeneration gas to reduce the impurity content of the sorbent stream; a first non-mechanical gas seal forming solids transfer device adapted to receive an impurity loaded sorbent stream from the absorber and transport the impurity loaded sorbent stream to the regenerator at a controllable flow rate in response to an aeration gas; and a second non-mechanical gas seal forming solids transfer device adapted to receive a sorbent stream of reduced impurity content from the regenerator and transfer the sorbent stream of reduced impurity content to the absorber without changing the flow rate of the sorbent stream.

  17. System Study: Residual Heat Removal 1998-2014

    SciTech Connect

    Schroeder, John Alton

    2015-12-01

    This report presents an unreliability evaluation of the residual heat removal (RHR) system in two modes of operation (low-pressure injection in response to a large loss-of-coolant accident and post-trip shutdown-cooling) at 104 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2014 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing trends were identified in the RHR results. A highly statistically significant decreasing trend was observed for the RHR injection mode start-only unreliability. Statistically significant decreasing trends were observed for RHR shutdown cooling mode start-only unreliability and RHR shutdown cooling model 24-hour unreliability.

  18. Dynamic simulation of sulfur-removal systems. Final report

    SciTech Connect

    Alexander, J.H.; Blake, T.R.; Brownell, D.H. Jr.; Henline, W.D.; Wilkins, D.E.

    1982-01-01

    A generalized computer simulation has been developed to predict the dynamic response of alternate gas absorption systems for selective removal of sulfur compounds or ammonia from fuel gas or synthesis gas produced from coal or other fossil fuels. The models use numerical methods based upon finite difference techniques to determine the spatial distribution of process variables within both the absorption and regeneration columns of such gas cleanup processes. The simulator may be applied to systems for selective gas absorption based on either chemical or physical principles. Examples of such systems include the Benfield process based on absorption by chemical reaction with an activated alkali carbonate solvent, and the Allied SELEXOL Solvent Process based on physical absorption as a result of partial pressure differences of the gas components above an organic solvent system. Simulations of either individual process units or an entire integrated plant can be performed. This computer program has specifically been structured to permit convenient flow sheet modification, as well as addition of new units. This research has emphasized the development of a general theoretical structure which can be easily modified by substituting alternate sets of data on the physicochemical properties of the appropriate liquid solvent. This model has been applied to Selexol Solvent Processes using both published and proprietary data on solvent properties. Test calculations have been performed to simulate open loop response of individual scrubber towers, and the complete system, to input composition and flow rate transients.

  19. Tank waste removal using a high pressure waterjet system

    SciTech Connect

    Randolph, J.D.; Rinker, M.W.; Summers, D.

    1996-10-01

    The Oak Ridge National Laboratory has several tank wastes that are currently stored in inactive tanks constructed of gunite concrete. A remediation program at ORNL and a development program at PNL and UMR are collaborating to develop a system that will utilize high pressure waterjet technology for cutting and dislodging sludge beds, and for conveyance of those materials to a treatment tank. This technology for waste removal has two major advantages. First, sludge will be retrieved from one or more high risk tanks, that is tanks with a high degree of uncertainty for failure, to a single treatment tank with lower risk. Second, sludges of similar nature will be consolidated for volume reduction. ORNL and PNL are currently pursuing this technology for waste removal and transport to a single immobilization treatment facility. The ORNL remediation program is known as the Gunite And Associated Tanks Treatability Study. The PNL development program is known as Retrieval Process Development and Enhancement. UMR is developing the waste dislodging/cutting tool. This paper will describe the waterjet technology for waste dislodging and conveyance of ORNL sludges from underground storage tanks.

  20. Band gaps, ionization potentials, and electron affinities of periodic electron systems via the adiabatic-connection fluctuation-dissipation theorem

    NASA Astrophysics Data System (ADS)

    Trushin, Egor; Betzinger, Markus; Blügel, Stefan; Görling, Andreas

    2016-08-01

    An approach to calculate fundamental band gaps, ionization energies, and electron affinities of periodic electron systems is explored. Starting from total energies obtained with the help of the adiabatic-connection fluctuation-dissipation (ACFD) theorem, these physical observables are calculated according to their basic definition by differences of the total energies of the N -, (N -1 ) -, and (N +1 ) -electron system. The response functions entering the ACFD theorem are approximated here by the direct random phase approximation (dRPA). For a set of prototypical semiconductors and insulators it is shown that even with this quite drastic approximation the resulting band gaps are very close to experiment and of a similar quality to those from the computationally more involved G W approximation. By going beyond the dRPA in the future the accuracy of the calculated band gaps may be significantly improved further.

  1. Evaluation of levonorgestrel intrauterine system upon presumed nonintact removal.

    PubMed

    Bukowski, Josh; Rogers, Anna; Cansino, Catherine

    2014-12-01

    A 51 year old woman presented for removal of her expired levonorgestrel intrauterine device (IUD). The IUD arms appeared absent upon IUD removal. Further examination of the device revealed that the arms were concealed inside the hormonal cylinder. Recognizing abnormal presentations of the levonorgestrel IUD upon removal can avoid unnecessary procedures.

  2. Dual regulation of the Arabidopsis high-affinity root iron uptake system by local and long-distance signals.

    PubMed

    Vert, Grégory A; Briat, Jean-François; Curie, Catherine

    2003-06-01

    Regulation of the root high-affinity iron uptake system by whole-plant signals was investigated at the molecular level in Arabidopsis, through monitoring FRO2 and IRT1 gene expression. These two genes encode the root ferric-chelate reductase and the high-affinity iron transporter, respectively, involved in the iron deficiency-induced uptake system. Recovery from iron-deficient conditions and modulation of apoplastic iron pools indicate that iron itself plays a major role in the regulation of root iron deficiency responses at the mRNA and protein levels. Split-root experiments show that the expression of IRT1 and FRO2 is controlled both by a local induction from the root iron pool and through a systemic pathway involving a shoot-borne signal, both signals being integrated to tightly control production of the root iron uptake proteins. We also show that IRT1 and FRO2 are expressed during the day and down-regulated at night and that this additional control is overruled by iron starvation, indicating that the nutritional status prevails on the diurnal regulation. Our work suggests, for the first time to our knowledge, that like in grasses, the root iron acquisition in strategy I plants may also be under diurnal regulation. On the basis of the new molecular insights provided in this study and given the strict coregulation of IRT1 and FRO2 observed, we present a model of local and long-distance regulation of the root iron uptake system in Arabidopsis.

  3. Conceptual design of an aircraft automated coating removal system

    SciTech Connect

    Baker, J.E.; Draper, J.V.; Pin, F.G.; Primm, A.H.; Shekhar, S.

    1996-05-01

    Paint stripping of the U.S. Air Force`s large transport aircrafts is currently a labor-intensive, manual process. Significant reductions in costs, personnel and turnaround time can be accomplished by the judicious use of automation in some process tasks. This paper presents the conceptual design of a coating removal systems for the tail surfaces of the C-5 plane. Emphasis is placed on the technology selection to optimize human-automation synergy with respect to overall costs, throughput, quality, safety, and reliability. Trade- offs between field-proven vs. research-requiring technologies, and between expected gain vs. cost and complexity, have led to a conceptual design which is semi-autonomous (relying on the human for task specification and disturbance handling) yet incorporates sensor- based automation (for sweep path generation and tracking, surface following, stripping quality control and tape/breach handling).

  4. Robust fuzzy output feedback controller for affine nonlinear systems via T-S fuzzy bilinear model: CSTR benchmark.

    PubMed

    Hamdy, M; Hamdan, I

    2015-07-01

    In this paper, a robust H∞ fuzzy output feedback controller is designed for a class of affine nonlinear systems with disturbance via Takagi-Sugeno (T-S) fuzzy bilinear model. The parallel distributed compensation (PDC) technique is utilized to design a fuzzy controller. The stability conditions of the overall closed loop T-S fuzzy bilinear model are formulated in terms of Lyapunov function via linear matrix inequality (LMI). The control law is robustified by H∞ sense to attenuate external disturbance. Moreover, the desired controller gains can be obtained by solving a set of LMI. A continuous stirred tank reactor (CSTR), which is a benchmark problem in nonlinear process control, is discussed in detail to verify the effectiveness of the proposed approach with a comparative study.

  5. Insights into the algebraic structure of Lorenz-like systems using feedback circuit analysis and piecewise affine models

    NASA Astrophysics Data System (ADS)

    Letellier, Christophe; Amaral, Gleison F. V.; Aguirre, Luis A.

    2007-06-01

    The characterization of chaotic attractors has been a widely addressed problem and there are now many different techniques to define their nature in a rather accurate way, at least in the case of a three-dimensional system. Nevertheless, the link between the structure of the ordinary differential equations and the topology of their solutions is still missing and only a few necessary conditions on the algebraic structure are known today. By using a feedback circuit analysis, it is shown that it is possible to identify the relevant terms of the equations, that is, the terms that really contribute to the structure of the phase portrait. Such analysis also provides some guidelines for constructing piecewise affine models. Moreover, equivalence classes can be defined on the basis of the active feedback circuits involved.

  6. A synthetic host-guest system achieves avidin-biotin affinity by overcoming enthalpy-entropy compensation.

    PubMed

    Rekharsky, Mikhail V; Mori, Tadashi; Yang, Cheng; Ko, Young Ho; Selvapalam, N; Kim, Hyunuk; Sobransingh, David; Kaifer, Angel E; Liu, Simin; Isaacs, Lyle; Chen, Wei; Moghaddam, Sarvin; Gilson, Michael K; Kim, Kimoon; Inoue, Yoshihisa

    2007-12-26

    The molecular host cucurbit[7]uril forms an extremely stable inclusion complex with the dicationic ferrocene derivative bis(trimethylammoniomethyl)ferrocene in aqueous solution. The equilibrium association constant for this host-guest pair is 3 x 10(15) M(-1) (K(d) = 3 x 10(-16) M), equivalent to that exhibited by the avidin-biotin pair. Although purely synthetic systems with larger association constants have been reported, the present one is unique because it does not rely on polyvalency. Instead, it achieves its extreme affinity by overcoming the compensatory enthalpy-entropy relationship usually observed in supramolecular complexes. Its disproportionately low entropic cost is traced to extensive host desolvation and to the rigidity of both the host and the guest.

  7. Using Wet-FGD systems for mercury removal.

    PubMed

    Díaz-Somoano, Mercedes; Unterberger, Sven; Hein, Klaus R G

    2005-09-01

    A plan to control mercury emissions to the atmosphere and to establish mercury emission limits has recently been elaborated by the European Commission, making it necessary to devise an efficient and cost effective mercury removal technology. Towards this end wet flue gas desulfurization units appear as a promising option for multi-pollutant control. However, more investigation on mercury removal and a greater mercury removal efficiency are required to achieve this objective. In the present work scrubber chemistry and the application of various solid additives to enhance mercury removal in wet scrubbers is evaluated. The results obtained show a significant correlation between mercury removal efficiency and the pH of the scrubber slurry and SO2 concentration. A weaker correlation was observed between oxygen or slurry concentration and removal efficiency. Finally several solid oxides were found to be effective additives for enhancing mercury capture in wet scrubbers.

  8. Biological phosphorus removal inhibition by roxarsone in batch culture systems.

    PubMed

    Guo, Qingfeng; Liu, Li; Hu, Zhenhu; Chen, Guowei

    2013-06-01

    Roxarsone has been extensively used in the feed of animals, which is usually excreted unchanged in the manure and eventually enter into animal wastewater, challenging the biological phosphorus removal processes. Knowledge of its inhibition effect is key for guiding treatment of roxarsone-contaminated wastewater, and is unfortunately keeping unclear. We study the inhibition of roxarsone on biological phosphorus removal processes for roxarsone-contaminated wastewater treatment, in terms of the removal and rates of chemical oxygen demand (COD), phosphate. Results showed that presence of roxarsone considerably limited the COD removals, especially at roxarsone concentration exceeding 40 mg L(-1). Additionally, roxarsone inhibited both phosphorus release and uptake processes, consistent with the phosphate profiles during the biological phosphorus removal processes; whereas, roxarsone is more toxic to phosphorus uptake process, than release function. The results indicated that it is roxarsone itself, rather than the inorganic arsenics, inhibit biological phosphorus removal processes within both aerobic and anaerobic roxarsone-contaminated wastewater treatment.

  9. ROGER a potential orbital space debris removal system

    NASA Astrophysics Data System (ADS)

    Starke, Juergen; Bischof, Bernd; Foth, W.-O.; -J., J.; Günther

    The previous activities in the field of On Orbit Servicing studied in the 1990's included in partic-ular the capability of vehicles in GEO to capture and support satellites (mainly communication satellites) to enable repair and continuation of operations, and finally the controlled transfer the target into a permanent graveyard orbit. The specific capture tools for these applications were mostly based on robotic systems to capture and fix the target under specific dynamic constraints (e.g. slowly tumbling target) without damage, and to allow the stabilization, re-orientation and potential repair of the target and subsequent release or transport to the final disposal orbit. Due to the drastically increasing number of debris particularly in the Low Earth Orbits (SSO) the active debris removal is now necessary to counteract to the predicted debris production cascade (Kessler Syndrome), which means the pollution of the total sphere in low earth orbit and not only the SSO area. In most of the debris congresses it was recommended to start removal with the still integrated systems as soon as possible. In the case of large debris objects, the soft capture system can be replaced by a simpler and robust system able to operate from a safe distance to the target and flexible enough to capture and hold different types of targets such as deactivated and/or defective satellites, upper stages and big fragments. These nominally non -cooperative targets might be partially destroyed by the capture process, but the production of additional debris shall be avoided. A major argument for the commercial applications is a multi-target mission potential, which is possible at GEO because the transfer propellant requirement to the disposal orbit and the return to the orbit of the next potential target is relative low (orbits with similar inclination and altitude). The proposed ROGER system is designed as a spacecraft with rendezvous capabilities including inspection in the vicinity of the

  10. Biochemical affinity sensing systems based on luminescence generation in the evanescent field of optical waveguides

    NASA Astrophysics Data System (ADS)

    Duveneck, Gert L.; Oroszlan, Peter; Abel, A. P.; Klee, B.; Steiner, V.; Ehrat, Markus; Gygax, D.; Widmer, H. M.

    1995-01-01

    We have developed a (bio)chemical analysis system based on luminescence generation and detection in the evanescent field associated with light guiding in an optical fiber. Our intention was directed towards optimization of not only the sensor, including the sensor handling and the immobilization of biochemical recognition elements, but also of the assay chemistry, with special emphasis on methods used for sensor regeneration, of the fluidic system, and of the experimental control software. Goals of this optimization process were not only to achieve high sensitivity, reproducibility and the related precision of the results, but also maximum regenerability of the sensors and system flexibility for a variety of different applications. Four examples of different bioaffinity assays, established on our sensor system, are presented: a competitive immunoassay for atrazine, a sandwich immunoassay for hirudin, a DNA hybridization assay, and first studies for the development of sensors based on membrane- bound receptors. In the atrazine assay, the sensor could be regenerated more than 300 times. In the hybridization assay, a detection limit of 7.5 multiplied by 10-14 M complementary fluorescein-labeled DNA was achieved. The performance of our system is compared with an established enzyme-linked immunosorbent assay (ELISA) on the example of the hirudin assay. In the concluding section of this paper, advantages and disadvantages of our fiberoptic, luminescence-based system, compared with commercialized systems, based on detection of changes of the effective refractive index, are discussed.

  11. Data-based fault-tolerant control for affine nonlinear systems with actuator faults.

    PubMed

    Xie, Chun-Hua; Yang, Guang-Hong

    2016-09-01

    This paper investigates the fault-tolerant control (FTC) problem for unknown nonlinear systems with actuator faults including stuck, outage, bias and loss of effectiveness. The upper bounds of stuck faults, bias faults and loss of effectiveness faults are unknown. A new data-based FTC scheme is proposed. It consists of the online estimations of the bounds and a state-dependent function. The estimations are adjusted online to compensate automatically the actuator faults. The state-dependent function solved by using real system data helps to stabilize the system. Furthermore, all signals in the resulting closed-loop system are uniformly bounded and the states converge asymptotically to zero. Compared with the existing results, the proposed approach is data-based. Finally, two simulation examples are provided to show the effectiveness of the proposed approach.

  12. Automated Immobilized Metal Affinity Chromatography System for Enrichment of Escherichia coli Phosphoproteome

    SciTech Connect

    Qu, Yi; Wu, Si; Zhao, Rui; Zink, Erika M.; Orton, Daniel J.; Moore, Ronald J.; Meng, Da; Clauss, Therese RW; Aldrich, Joshua T.; Lipton, Mary S.; Pasa-Tolic, Ljiljana

    2013-06-05

    Enrichment of bacterial phosphopeptides is an essential step prior to bottom-up mass spectrometry-based analysis of the phosphoproteome, which is fundamental to understanding the role of phosphoproteins in cell signaling and regulation of protein activity. We developed an automated IMAC system to enrich strong cation exchange-fractionated phosphopeptides from the soluble proteome of Escherichia coli MG1655 grown on minimal medium. Initial demonstration of the system resulted in identification of 75 phosphopeptides covering 52 phosphoproteins. Consistent with previous studies, many of these phosphoproteins are involved in the carbohydrate portion of central metabolism. The automated system utilizes a large capacity IMAC column that can effectively enrich phosphopeptides from a bacterial sample by increasing peptide loading and reducing the wash time. An additional benefit of the automated IMAC system is reduced labor and associated costs.

  13. Removal of organic micropollutants in an artificial recharge system

    NASA Astrophysics Data System (ADS)

    Valhondo, C.; Nödler, K.; Köck-Schulmeyer, M.; Hernandez, M.; Licha, T.; Ayora, C.; Carrera, J.

    2012-04-01

    Emerging contaminants including pharmaceutically active compounds (PhACs), personal care products (PCPs) and pesticides are increasingly being identified in the environment. Emerging pollutants and their transformation products show low concentration in the environment (ng/L), but the effects of the mixtures and lifelong exposure to humans are currently unknown. Many of these contaminants are removed under aerobic conditions in water treatment plants. However, several pharmaceuticals and metabolites present in wastewater are not eliminated by conventional treatment processes. Several lab studies, however, show that the behaviour of many of these micropollutants is affected by the dominant redox conditions. However, data from field experiments are limited and sometimes contradictory. Artificial recharge is a widespread technology to increase the groundwater resources. In this study we propose a design to enhance the natural remediation potential of the aquifer with the installation of a reactive layer at the bottom of the infiltration pond. This layer is a mixture of compost, aquifer material, clay and iron oxide. This layer is intended to provide an extra amount of DOC to the recharge water and to promote biodegradation by means of the development of different redox zones along the travel path through the unsaturated zone and within the aquifer. Moreover, compost, clay and iron oxide of the layer are assumed to increase sorption surfaces for neutral, cationic and anionic compounds, respectively. The infiltration system is sited in Sant Vicenç dels Horts (Barcelona, Spain). It consists of a decantation pond, receiving raw water from the Llobregat River (highly affected from treatment plant effluents), and an infiltration pond (5600 m2). The infiltration rate is around 1 m3/m2/day. The system is equipped with a network of piezometers, suction cups and tensiometers. Infiltration periods have been performed before and after the installation of the reactive layer

  14. Fructose Uptake in Sinorhizobium meliloti Is Mediated by a High-Affinity ATP-Binding Cassette Transport System

    PubMed Central

    Lambert, Annie; Østerås, Magne; Mandon, Karine; Poggi, Marie-Christine; Le Rudulier, Daniel

    2001-01-01

    By transposon mutagenesis, we have isolated a mutant of Sinorhizobium meliloti which is totally unable to grow on fructose as sole carbon source as a consequence of its inability to transport this sugar. The cloning and sequencing analysis of the chromosomal DNA region flanking the TnphoA insertion revealed the presence of six open reading frames (ORFs) organized in two loci, frcRS and frcBCAK, transcribed divergently. The frcBCA genes encode the characteristic components of an ATP-binding cassette transporter (FrcB, a periplasmic substrate binding protein, FrcC, an integral membrane permease, and FrcA, an ATP-binding cytoplasmic protein), which is the unique high-affinity (Km of 6 μM) fructose uptake system in S. meliloti. The FrcK protein shows homology with some kinases, while FrcR is probably a transcriptional regulator of the repressor-ORF-kinase family. The expression of S. meliloti frcBCAK in Escherichia coli, which transports fructose only via the phosphotransferase system, resulted in the detection of a periplasmic fructose binding activity, demonstrating that FrcB is the binding protein of the Frc transporter. The analysis of substrate specificities revealed that the Frc system is also a high-affinity transporter for ribose and mannose, which are both fructose competitors for the binding to the periplasmic FrcB protein. However, the Frc mutant was still able to grow on these sugars as sole carbon source, demonstrating the presence of at least one other uptake system for mannose and ribose in S. meliloti. The expression of the frcBC genes as determined by measurements of alkaline phosphatase activity was shown to be induced by mannitol and fructose, but not by mannose, ribose, glucose, or succinate, suggesting that the Frc system is primarily targeted towards fructose. Neither Nod nor Fix phenotypes were impared in the TnphoA mutant, demonstrating that fructose uptake is not essential for nodulation and nitrogen fixation, although FrcB protein is

  15. Fructose uptake in Sinorhizobium meliloti is mediated by a high-affinity ATP-binding cassette transport system.

    PubMed

    Lambert, A; Østerås, M; Mandon, K; Poggi, M C; Le Rudulier, D

    2001-08-01

    By transposon mutagenesis, we have isolated a mutant of Sinorhizobium meliloti which is totally unable to grow on fructose as sole carbon source as a consequence of its inability to transport this sugar. The cloning and sequencing analysis of the chromosomal DNA region flanking the TnphoA insertion revealed the presence of six open reading frames (ORFs) organized in two loci, frcRS and frcBCAK, transcribed divergently. The frcBCA genes encode the characteristic components of an ATP-binding cassette transporter (FrcB, a periplasmic substrate binding protein, FrcC, an integral membrane permease, and FrcA, an ATP-binding cytoplasmic protein), which is the unique high-affinity (K(m) of 6 microM) fructose uptake system in S. meliloti. The FrcK protein shows homology with some kinases, while FrcR is probably a transcriptional regulator of the repressor-ORF-kinase family. The expression of S. meliloti frcBCAK in Escherichia coli, which transports fructose only via the phosphotransferase system, resulted in the detection of a periplasmic fructose binding activity, demonstrating that FrcB is the binding protein of the Frc transporter. The analysis of substrate specificities revealed that the Frc system is also a high-affinity transporter for ribose and mannose, which are both fructose competitors for the binding to the periplasmic FrcB protein. However, the Frc mutant was still able to grow on these sugars as sole carbon source, demonstrating the presence of at least one other uptake system for mannose and ribose in S. meliloti. The expression of the frcBC genes as determined by measurements of alkaline phosphatase activity was shown to be induced by mannitol and fructose, but not by mannose, ribose, glucose, or succinate, suggesting that the Frc system is primarily targeted towards fructose. Neither Nod nor Fix phenotypes were impared in the TnphoA mutant, demonstrating that fructose uptake is not essential for nodulation and nitrogen fixation, although FrcB protein is

  16. Costs of Arsenic Removal Technologies for Small Water Systems: U.S. EPA Arsenic Removal Technology Demonstration Program

    EPA Science Inventory

    As part of the Arsenic Rule Implementation Research Program, between July 2003 and July 2011, the U.S. environmental Protection Agency (EPA) conducted 50 full-scale demonstration projects on treatment systems removing arsenic from drinking water in 26 states throughout the U.S. ...

  17. Assessment of sulfur removal processes for advanced fuel cell systems

    NASA Astrophysics Data System (ADS)

    Lorton, G. A.

    1980-01-01

    The performance characteristics of potential sulfur removal processes were evaluated and four of these processes, the Selexol process, the Benfield process, the Sulfinol process, and the Rectisol process, were selected for detailed technical and economic comparison. The process designs were based on a consistent set of technical criteria for a grass roots facility with a capacity of 10,000 tons per day of Illinois No. 6 coal. Two raw gas compositions, based on oxygen blown and air blown Texaco gasification, were used. The bulk of the sulfur was removed in the sulfur removal unit, leaving a small amount of sulfur compounds in the gas. The remaining sulfur compounds were removed by reaction with zinc oxide in the sulfur polishing unit. The impact of COS hydrolysis pretreatment on sulfur removal was evaluated. Comprehensive capital and O and M cost estimates for each of the process schemes were developed.

  18. Method for removing tilt control in adaptive optics systems

    DOEpatents

    Salmon, Joseph Thaddeus

    1998-01-01

    A new adaptive optics system and method of operation, whereby the method removes tilt control, and includes the steps of using a steering mirror to steer a wavefront in the desired direction, for aiming an impinging aberrated light beam in the direction of a deformable mirror. The deformable mirror has its surface deformed selectively by means of a plurality of actuators, and compensates, at least partially, for existing aberrations in the light beam. The light beam is split into an output beam and a sample beam, and the sample beam is sampled using a wavefront sensor. The sampled signals are converted into corresponding electrical signals for driving a controller, which, in turn, drives the deformable mirror in a feedback loop in response to the sampled signals, for compensating for aberrations in the wavefront. To this purpose, a displacement error (gradient) of the wavefront is measured, and adjusted by a modified gain matrix, which satisfies the following equation: G'=(I-X(X.sup.T X).sup.-1 X.sup.T)G(I-A)

  19. Method for removing tilt control in adaptive optics systems

    DOEpatents

    Salmon, J.T.

    1998-04-28

    A new adaptive optics system and method of operation are disclosed, whereby the method removes tilt control, and includes the steps of using a steering mirror to steer a wavefront in the desired direction, for aiming an impinging aberrated light beam in the direction of a deformable mirror. The deformable mirror has its surface deformed selectively by means of a plurality of actuators, and compensates, at least partially, for existing aberrations in the light beam. The light beam is split into an output beam and a sample beam, and the sample beam is sampled using a wavefront sensor. The sampled signals are converted into corresponding electrical signals for driving a controller, which, in turn, drives the deformable mirror in a feedback loop in response to the sampled signals, for compensating for aberrations in the wavefront. To this purpose, a displacement error (gradient) of the wavefront is measured, and adjusted by a modified gain matrix, which satisfies the following equation: G{prime} = (I{minus}X(X{sup T} X){sup {minus}1}X{sup T})G(I{minus}A). 3 figs.

  20. Functions & Requirements for Debris Removal System Project A-2

    SciTech Connect

    PRECECHTEL, D.R.

    1999-12-29

    This revision of the Functions and Requirements Document updates the approved Functions and Requirements for Debris Removal Subproject WHC-SD-SNF-FRD-009, Rev. 0. It has been revised in its entirety to reflect the current scope of work for Debris Removal as canisters and lids under the K Basin Projects work breakdown structure (WBS). In this revision the canisters and lids will be consider debris and a new set of Functions and Requirements have been developed to remove the canisters and lids from the basin.

  1. Development of Vapor-Phase Catalytic Ammonia Removal System

    NASA Technical Reports Server (NTRS)

    Flynn, Michael; Fisher, John; Kiss, Mark; Borchers, Bruce; Tleimat, Badawi; Tleimat, Maher; Quinn, Gregory; Fort, James; Nalette, Tim; Baker, Gale; Genovese, Joseph

    2007-01-01

    A report describes recent accomplishments of a continuing effort to develop the vapor-phase catalytic ammonia removal (VPCAR) process for recycling wastewater for consumption by humans aboard a spacecraft in transit to Mars.

  2. Laser balancing system for high material removal rates

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Georgalas, G.; Ortiz, A. L.

    1984-01-01

    A laser technique to remove material in excess of 10 mg/sec from a spinning rotor is described. This material removal rate is 20 times greater than previously reported for a surface speed of 30 m/sec. Material removal enhancement was achieved by steering a focused laser beam with moving optics to increase the time of laser energy interaction with a particular location on the circumferential surface of a spinning rotor. A neodymium:yttrium aluminum garnet (Nd:YAG) pulse laser was used in this work to evaluate material removal for carbon steel, 347 stainless steel, Inconal 718, and titanium 6-4. This technique is applicable to dynamic laser balancing.

  3. A novel membrane distillation-thermophilic bioreactor system: biological stability and trace organic compound removal.

    PubMed

    Wijekoon, Kaushalya C; Hai, Faisal I; Kang, Jinguo; Price, William E; Guo, Wenshan; Ngo, Hao H; Cath, Tzahi Y; Nghiem, Long D

    2014-05-01

    The removal of trace organic compounds (TrOCs) by a novel membrane distillation-thermophilic bioreactor (MDBR) system was examined. Salinity build-up and the thermophilic conditions to some extent adversely impacted the performance of the bioreactor, particularly the removal of total nitrogen and recalcitrant TrOCs. While most TrOCs were well removed by the thermophilic bioreactor, compounds containing electron withdrawing functional groups in their molecular structure were recalcitrant to biological treatment and their removal efficiency by the thermophilic bioreactor was low (0-53%). However, the overall performance of the novel MDBR system with respect to the removal of total organic carbon, total nitrogen, and TrOCs was high and was not significantly affected by the conditions of the bioreactor. All TrOCs investigated here were highly removed (>95%) by the MDBR system. Biodegradation, sludge adsorption, and rejection by MD contribute to the removal of TrOCs by MDBR treatment.

  4. G196 epitope tag system: a novel monoclonal antibody, G196, recognizes the small, soluble peptide DLVPR with high affinity

    PubMed Central

    Tatsumi, Kasumi; Sakashita, Gyosuke; Nariai, Yuko; Okazaki, Kosuke; Kato, Hiroaki; Obayashi, Eiji; Yoshida, Hisashi; Sugiyama, Kanako; Park, Sam-Yong; Sekine, Joji; Urano, Takeshi

    2017-01-01

    The recognition specificity of monoclonal antibodies (mAbs) has made mAbs among the most frequently used tools in both basic science research and in clinical diagnosis and therapies. Precise determination of the epitope allows the development of epitope tag systems to be used with recombinant proteins for various purposes. Here we describe a new family of tag derived from the epitope recognized by a highly specific mAb G196. The minimal epitope was identified as the five amino acid sequence Asp-Leu-Val-Pro-Arg. Permutation analysis was used to characterize the binding requirements of mAb G196, and the variable regions of the mAb G196 were identified and structurally analyzed by X-ray crystallography. Isothermal titration calorimetry revealed the high affinity (Kd = 1.25 nM) of the mAb G196/G196-epitope peptide interaction, and G196-tag was used to detect several recombinant cytosolic and nuclear proteins in human and yeast cells. mAb G196 is valuable for developing a new peptide tagging system for cell biology and biochemistry research. PMID:28266535

  5. Video requirements plan for the HMT equipment removal system

    SciTech Connect

    Vargo, G.F. Jr.

    1995-02-01

    This document is the plan defining the video coverage requirements for the equipment removal event of the Hydrogen Mitigation Test (HMT) mixer pump currently installed in high level nuclear waste storage Tank 241-SY-101. When the mixer pump fails the removal and installation of a spare pump will be a time critical event. Since the success of the HMT mixer pump has resolved the DOE safety issue it is absolutely essential that mixing be restored to the tank in a short as time possible. Therefore, the removal of the failed pump and the installation of the spare pump must be anticipated and planned well in advance. The removal, containment, transporting, and storage of the failed pump is a very complex and hazardous task. The successful completion of this task will require careful planning and monitoring. Certain events, during the removal and subsequent installation of the new pump, will require video observation and storage for safety, documenting, training, and promotional use. Furthermore, certain events will require close monitoring and observation by the event directors and key supervisory personnel for the execution of specific tasks during the equipment removal event.

  6. Biologically-based signal processing system applied to noise removal for signal extraction

    DOEpatents

    Fu, Chi Yung; Petrich, Loren I.

    2004-07-13

    The method and system described herein use a biologically-based signal processing system for noise removal for signal extraction. A wavelet transform may be used in conjunction with a neural network to imitate a biological system. The neural network may be trained using ideal data derived from physical principles or noiseless signals to determine to remove noise from the signal.

  7. Immobilized metal ion affinity partitioning, a method combining metal-protein interaction and partitioning of proteins in aqueous two-phase systems.

    PubMed

    Birkenmeier, G; Vijayalakshmi, M A; Stigbrand, T; Kopperschläger, G

    1991-02-22

    Immobilized metal ions were used for the affinity extraction of proteins in aqueous two-phase systems composed of polyethylene glycol (PEG) and dextran or PEG and salt. Soluble chelating polymers were prepared by covalent attachment of metal-chelating groups to PEG. The effect on the partitioning of proteins of such chelating PEG derivatives coordinated with different metal ions is demonstrated. The proteins studied were alpha 2-macroglobulin, tissue plasminogen activator, superoxide dismutase and monoclonal antibodies. The results indicate that immobilized metal ion affinity partitioning provides excellent potential for the extraction of proteins.

  8. Mechanism of the influence of EGTA on the affinity of the Ca-transporting and Ca-binding systems of the cell for calcium

    SciTech Connect

    Orolv, S.N.; Sitozhevskii, A.V.; Pokudin, N.I.; Agnaev, V.M.

    1986-05-20

    The activity of Ca-ATPases of erythrocyte ghosts and the sarcoplasmic reticulum, as the rate of ATP-dependent uptake of /sup 44/Ca by inside-out vesicles of erythrocyte membranes, vesicles of sarcoplasmic reticulum and mitochondria, was investigated. Evidently in all cases, the introduction of EGTA into the incubation medium leads to an increase in the affinity of the Ca-pumps for Ca/sup 2 +/ without any change in their maximum activity. An analogous effect of EGTA was detected in a determination of the affinity of Ca/sup 2 +/ of calmodulin, troponin S, and the fluorescent dye quin 2. It is suggested that the action of EGTA on the affinity of the Ca-transporting and Ca-binding systems of the cell for Ca/sup 2 +/ is associated with displacement of impurities of di- and trivalent cations.

  9. A molecular recognizing system of serotonin in rat fetal axonal growth cones: uptake and high affinity binding.

    PubMed

    Mercado, R; Hernández, J

    1992-09-18

    Axonal growth cone particles (AGCP) isolated from prenatal and postnatal rat brain had different high-affinity 5-HT uptake characteristics. In postnatal AGCP the uptake behaves as in the adult rat brain, while in the prenatal AGCP the uptake characteristics seem to be in a transitional stage. Also in prenatal AGCP we observed specific, high-affinity 5-HT binding sites. These results support the idea of an important role for 5-HT during axogenesis.

  10. Assessment of sulfur removal processes for advanced fuel cell systems

    SciTech Connect

    Lorton, G.A.

    1980-01-01

    This study consisted of a technical evaluation and economic comparison of sulfur removal processes for integration into a coal gasification-molten carbonate (CGMC) fuel cell power plant. Initially, the performance characteristics of potential sulfur removal processes were evaluated and screened for conformance to the conditions and requirements expected in commercial CGMC power plants. Four of these processes, the Selexol process, the Benfield process, the Sulfinol process, and the Rectisol process, were selected for detailed technical and economic comparison. The process designs were based on a consistent set of technical criteria for a grass roots facility with a capacity of 10,000 tons per day of Illinois No. 6 coal. Two raw gas compositions, based on oxygen-blown and air-blown Texaco gasification, were used. The bulk of the sulfur was removed in the sulfur removal unit, leaving a small amount of sulfur compounds in the gas (1 ppMv or 25 ppMv). The remaining sulfur compounds were removed by reaction with zinc oxide in the sulfur polishing unit. The impact of COS hydrolysis pretreatment on sulfur removal was evaluated. Comprehensive capital and O and M cost estimates for each of the process schemes were developed for the essentially complete removal of sulfur compounds. The impact on the overall plant performance was also determined. The total capital requirement for sulfur removal schemes ranged from $59.4/kW to $84.8/kW for the oxygen-blown cases and from $89.5/kW to $133/kW for the air-blown cases. The O and M costs for sulfur removal for 70% plant capacity factor ranged from 0.82 mills/kWh to 2.76 mills/kWh for the oxygen-blown cases and from 1.77 mills/kWh to 4.88 mills/kWh for the air-blown cases. The Selexol process benefitted the most from the addition of COS hydrolysis pretreatment.

  11. Mobile system for microwave removal of concrete surfaces

    DOEpatents

    White, Terry L.; Bigelow, Timothy S.; Schaich, Charles R.; Foster, Jr., Don

    1997-01-01

    A method and apparatus for the microwave removal of contaminated concrete surfaces. The apparatus comprises a housing adapted to pass over a support surface. The housing includes a waveguide for directing microwave energy to the surface at an angle maximizing absorption of microwave energy by the surface. The apparatus is further provided with a source of microwave energy operably associated with the waveguide, wherein the microwave energy has a frequency of between about 10.6 GHz and about 24 GHz and acts to remove the uppermost layer from the surface. The apparatus further includes a debris containment assembly comprising a vacuum assembly operably associated with the housing. The vacuum assembly is adapted to remove debris from the area adjacent the surface.

  12. Mobile system for microwave removal of concrete surfaces

    DOEpatents

    White, T.L.; Bigelow, T.S.; Schaich, C.R.; Foster, D. Jr.

    1997-06-03

    A method and apparatus are disclosed for the microwave removal of contaminated concrete surfaces. The apparatus comprises a housing adapted to pass over a support surface. The housing includes a waveguide for directing microwave energy to the surface at an angle maximizing absorption of microwave energy by the surface. The apparatus is further provided with a source of microwave energy operably associated with the waveguide, wherein the microwave energy has a frequency of between about 10.6 GHz and about 24 GHz and acts to remove the uppermost layer from the surface. The apparatus further includes a debris containment assembly comprising a vacuum assembly operably associated with the housing. The vacuum assembly is adapted to remove debris from the area adjacent the surface. 7 figs.

  13. Human motion capturing system with MEMS accelerometers (notice of removal)

    NASA Astrophysics Data System (ADS)

    Xiao, Baoping; Xu, Chang; Xu, Lijun; Ouyang, Shuigeng

    2007-11-01

    This paper (672413) was removed from the SPIE Digital Library on 13 April 2010 to discovery of plagiarism. As stated in the SPIE Guidelines for Professional Conduct and Publishing Ethics, SPIE defines plagiarism as the reuse of someone else's prior ideas, processes, results, or words without explicit attribution of the original author and source, or falsely representing someone else's work as one's own. SPIE considers plagiarism in any form, at any level, to be unacceptable and a serious breach of professional conduct. It is SPIE policy to remove such papers and to take appropriate corrective or disciplinary action against the offending author(s).

  14. Biphasic Affinity Chromatographic Approach for Deep Tyrosine Phosphoproteome Analysis.

    PubMed

    Deng, Zhenzhen; Dong, Mingming; Wang, Yan; Dong, Jing; Li, Shawn S-C; Zou, Hanfa; Ye, Mingliang

    2017-02-21

    Tyrosine phosphorylation (pTyr) is important for normal physiology and implicated in many human diseases, particularly cancer. Identification of pTyr sites is critical to dissecting signaling pathways and understanding disease pathologies. However, compared with serine/threonine phosphorylation (pSer/pThr), the analysis of pTyr at the proteome level is more challenging due to its low abundance. Here, we developed a biphasic affinity chromatographic approach where Src SH2 superbinder was coupled with NeutrAvidin affinity chromatography, for tyrosine phosphoproteome analysis. With the use of competitive elution agent biotin-pYEEI, this strategy can distinguish high-affinity phosphotyrosyl peptides from low-affinity ones, while the excess competitive agent is readily removed by using NeutrAvidin agarose resin in an integrated tip system. The excellent performance of this system was demonstrated by analyzing tyrosine phosphoproteome of Jurkat cells from which 3,480 unique pTyr sites were identified. The biphasic affinity chromatography method for deep Tyr phosphoproteome analysis is rapid, sensitive, robust, and cost-effective. It is widely applicable to the global analysis of the tyrosine phosphoproteome associated with tyrosine kinase signal transduction.

  15. Hemoglobin Ypsilanti: a high-oxygen-affinity hemoglobin demonstrated by two automated high-pressure liquid chromatography systems.

    PubMed

    Mais, Daniel D; Boxer, Laurence A; Gulbranson, Ronald D; Keren, David F

    2007-11-01

    Hemoglobin (Hb) Ypsilanti is a rare high-oxygen-affinity hemoglobin. Like other high-oxygen-affinity hemoglobins, Hb Ypsilanti manifests as erythrocytosis. Because the migration of many high-oxygen-affinity variants on alkaline and acid gels does not differ from that of HbA, oxygen-hemoglobin dissociation studies are often used to document their presence. Hb Ypsilanti is a notable exception because its electrophoresis pattern on alkaline gel is highly characteristic, exemplifying the phenomenon of hybrid formation in variant hemoglobins. In the past few years, several laboratories have begun to use high-pressure liquid chromatography (HPLC) as a screen for hemoglobinopathies. We demonstrate the elution profile of Hb Ypsilanti on the 2 most widely used HPLC methods.

  16. Evaluation of a liquid chemical scrubber system for styrene removal

    SciTech Connect

    Felix, L.; Merritt, R.; Williamson, A.

    1994-12-01

    The report gives results of a study of the styrene removal efficiency of a pilot-scale version of the QUAD Chemtact scrubber, quantified by continuously measuring the total hydrocarbon (THC) content of spray booth exhaust air entering and exiting the device with THC analyzers and, for some tests, by collecting EPA Method 18 samples (adsorption tube procedure) at the inlet and exit of the device. Average styrene removal efficiencies approached but were never >55%. The test was carried out at a facility (Eljer Plumbingware in Wilson, NC) that manufactures polyester bathtubs and shower stalls by spraying styrene-based resins onto molds in vented, open spray booths. A side stream of air, exhausted from one of the spray booths in the gel coating part of the process, was used for the test.

  17. Alternatives Generation Analysis Long Length Contaminated Equipment Removal System Storage

    SciTech Connect

    BOGER, R.M.

    1999-08-13

    The long length contaminated equipment was designed and built to aid in the remote removal and transport of highly radioactive, contaminated equipment from various locations in the tank farms to disposal. The equipment has been stored in an open lay-down yard area, exposed to the elements for the past year and a half. The possible alternatives available to provide shelter for the equipment are investigated.

  18. Advanced coal-fueled industrial cogeneration gas turbine system particle removal system development

    SciTech Connect

    Stephenson, M.

    1994-03-01

    Solar Turbines developed a direct coal-fueled turbine system (DCFT) and tested each component in subscale facilities and the combustion system was tested at full-scale. The combustion system was comprised of a two-stage slagging combustor with an impact separator between the two combustors. Greater than 90 percent of the native ash in the coal was removed as liquid slag with this system. In the first combustor, coal water slurry mixture (CWM) was injected into a combustion chamber which was operated loan to suppress NO{sub x} formation. The slurry was introduced through four fuel injectors that created a toroidal vortex because of the combustor geometry and angle of orientation of the injectors. The liquid slag that was formed was directed downward toward an impaction plate made of a refractory material. Sixty to seventy percent of the coal-borne ash was collected in this fashion. An impact separator was used to remove additional slag that had escaped the primary combustor. The combined particulate collection efficiency from both combustors was above 95 percent. Unfortunately, a great deal of the original sulfur from the coal still remained in the gas stream and needed to be separated. To accomplish this, dolomite or hydrated lime were injected in the secondary combustor to react with the sulfur dioxide and form calcium sulfite and sulfates. This solution for the sulfur problem increased the dust concentrations to as much as 6000 ppmw. A downstream particulate control system was required, and one that could operate at 150 psia, 1850-1900{degrees}F and with low pressure drop. Solar designed and tested a particulate rejection system to remove essentially all particulate from the high temperature, high pressure gas stream. A thorough research and development program was aimed at identifying candidate technologies and testing them with Solar`s coal-fired system. This topical report summarizes these activities over a period beginning in 1987 and ending in 1992.

  19. Feed gas contaminant removal in ion transport membrane systems

    DOEpatents

    Underwood, Richard Paul [Allentown, PA; Makitka, III, Alexander; Carolan, Michael Francis [Allentown, PA

    2012-04-03

    An oxygen ion transport membrane process wherein a heated oxygen-containing gas having one or more contaminants is contacted with a reactive solid material to remove the one or more contaminants. The reactive solid material is provided as a deposit on a support. The one or more contaminant compounds in the heated oxygen-containing gas react with the reactive solid material. The contaminant-depleted oxygen-containing gas is contacted with a membrane, and oxygen is transported through the membrane to provide transported oxygen.

  20. Modelling Cr(VI) removal by a combined carbon-activated sludge system.

    PubMed

    Orozco, A Micaela Ferro; Contreras, Edgardo M; Zaritzky, Noemí E

    2008-01-15

    The combined carbon-activated sludge process has been proposed as an alternative to protect the biomass against toxic substances in wastewaters; however, the information about the effect of powdered-activated carbon (PAC) addition in activated sludge reactors for the treatment of wastewaters containing Cr(VI) is limited. The objectives of the present study were: (a) to evaluate the removal of hexavalent chromium by (i) activated sludge microorganisms in aerobic batch reactors, (ii) powdered-activated carbon, and (iii) the combined action of powdered-activated carbon and biomass; (b) to propose mathematical models that interpret the experimental results. Different Cr(VI) removal systems were tested: (S1) biomass (activated sludge), (S2) PAC, and (S3) the combined activated carbon-biomass system. A Monod-based mathematical model was used to describe the kinetics of Cr(VI) removal in the system S1. A first-order kinetics with respect to Cr(VI) and PAC respectively, was proposed to model the removal of Cr(VI) in the system S2. Cr(VI) removal in the combined carbon-biomass system (S3) was faster than both Cr(VI) removal using PAC or activated sludge individually. Results showed that the removal of Cr(VI) using the activated carbon-biomass system (S3) was adequately described by combining the kinetic equations proposed for the systems S1 and S2.

  1. BOA II: Asbestos Pipe-Insulation Removal Robot System. Innovative Technology Summary Report.

    SciTech Connect

    2001-09-01

    The objective of this task is to develop and demonstrate a mechanical, asbestos-removal system that can be remotely operated without a containment area. The technology, known as BOA, consists of a pipe-crawler removal head and a boom vehicle system with dual robots. BOA's removal head can be remotely placed on the outside of the pipe and can crawl along the pipe, removing lagging and insulation. The lagging and insulation is cut using a hybrid endmill water-jet cutter and then diced into 2-inch cube sections of ACM. These ACM sections are then removed from the pipe using a set of blasting fan- spray nozzles, vacuumed off through a vacuum hose, and bagged. Careful attention to vacuum and entrapment air flow ensures that the system can operate without a containment area while meeting local and federal standards for fiber count.

  2. Enhanced fermentation systems with continuous removal of inhibitory products

    SciTech Connect

    Davison, B.H.; Kaufman, E.N.

    1994-06-01

    A variety of advanced bioreactors are being developed to improve production of fuels, solvents, organic acids, and other fermentation products. A major limitation of microbial fermentations is the dilute aqueous product streams that result, largely due to inhibition of the microbes by the desired products. If these inhibitory products can be removed during the ongoing fermentation, the overall rates, yields, and net product formation may be increased. Simultaneous fermentation and separation have been tested with different separation techniques, such as adsorption, liquid extraction, pervaporation, membrane separations, distillation, and others. These separations can occur directly in situ within the fermentor or indirectly using a sidestream separator with recycle of the unused substrate. These approaches are briefly reviewed. At Oak Ridge National Laboratory (ORNL), we have investigated two modified immobilized-cell fluidized-bed bioreactors (FBRs) to remove the inhibitory product directly from the continuous fermentation. One involves the separation by adsorption of tactic acid, and the other uses liquid solvent extraction for the production of butanol. Keywords: extractive fermentation, in situ separation, adsorption, tactic acid, butanol.

  3. Phosphate reduction in a hydroxyapatite fluoride removal system

    NASA Astrophysics Data System (ADS)

    Egner, A.

    2012-12-01

    Fluorosis is a widespread disease that occurs as a result of excess fluoride consumption and can cause severe tooth and bone deformations. To combat fluorosis, several previous studies have examined the potential to replace traditional bone char filters with synthetic hydroxyapatite. Calcite particles with a synthetic hydroxyapatite coating have been shown to effectively removed fluoride, yet the low-cost method for forming these particles leaves high amounts of phosphate both in synthesis waste-water and in filter effluent. High phosphate in filter effluent is problematic because consumption of extremely high phosphate can leach calcium from bones, further exacerbating the fluoride effect. This study examines ways of reducing and reusing waste. In particular, a method of fluoride removal is explored in which fluorapatite coatings may be formed directly. In preliminary studies, batches of 4.1g of Florida limestone (<710 μm) were equilibrated with 100 mL of 10ppm fluoride. In a control batch containing lime but no added phosphate, 14% treatment was achieved, but with added phosphate, 100% treatment was achieved in all batches. Batches with lower levels of phosphate took longer to reach 100% treatment, ranging from less than 24 hours in the highest phosphate batches to approximately 42 hours in the lowest batches. The lower levels tested were well within reasonable levels for drinking water and reached 0ppm fluoride in 42 hours or less.

  4. Capital and Operating Cost of Small Arsenic Removal System and their Most Frequent Maintenance Problems

    EPA Science Inventory

    This presentation will first summarize the capital and operating cost of treatment systems by type and size of the systems. The treatment systems include adsorptive media (AM) systems, iron removal (IR), coagulation/filtration (CF), ion exchange (IX) systems, and point-of-use rev...

  5. Predictable Therma-fil removal technique using the system-B heat source.

    PubMed

    Guess, Garrett M

    2004-01-01

    A clinical tip is suggested to assist in the removal of Therma-fil obturators during conventional endodontic retreatment. Using a heat source such as the System-B, the plastic carriers that are normally an obstacle to retreatment can be efficiently removed using the technique described.

  6. 300 GPM Solids Removal System A True Replacement for Back Flushable Powdered Filter Systems - 13607

    SciTech Connect

    Ping, Mark R.; Lewis, Mark

    2013-07-01

    The EnergySolutions Solids Removal System (SRS) utilizes stainless steel cross-flow ultra-filtration (XUF) technology which allows it to reliably remove suspended solids greater than one (1) micron from liquid radwaste streams. The SRS is designed as a pre-treatment step for solids separation prior to processing through other technologies such as Ion Exchange Resin (IER) and/or Reverse Osmosis (RO), etc. Utilizing this pre-treatment approach ensures successful production of reactor grade water while 1) decreasing the amount of radioactive water being discharged to the environment; and 2) decreasing the amount of radioactive waste that must ultimately be disposed of due to the elimination of spent powdered filter media. (authors)

  7. Active Debris Removal System Based on Polyurethane Foam

    NASA Astrophysics Data System (ADS)

    Rizzitelli, Federico; Valdatta, Marcelo; Bellini, Niccolo; Candini Gian, Paolo; Rastelli, Davide; Romei, Fedrico; Locarini, Alfredo; Spadanuda, Antonio; Bagassi, Sara

    2013-08-01

    Space debris is an increasing problem. The exponential increase of satellite launches in the last 50 years has determined the problem of space debris especially in LEO. The remains of past missions are dangerous for both operative satellites and human activity in space. But not only: it has been shown that uncontrolled impacts between space objects can lead to a potentially dangerous situation for civil people on Earth. It is possible to reach a situation of instability where the big amount of debris could cause a cascade of collisions, the so called Kessler syndrome, resulting in the infeasibility of new space missions for many generations. Currently new technologies for the mitigation of space debris are under study: for what concerning the removal of debris the use of laser to give a little impulse to the object and push it in a graveyard orbit or to be destroyed in the atmosphere. Another solution is the use of a satellite to rendezvous with the space junk and then use a net to capture it and destroy it in the reentry phase. In a parallel way the research is addressed to the study of deorbiting solutions to prevent the formation of new space junk. The project presented in this paper faces the problem of how to deorbit an existing debris, applying the studies about the use of polyurethane foam developed by Space Robotic Group of University of Bologna. The research is started with the Redemption experiment part of last ESA Rexus program. The foam is composed by two liquid components that, once properly mixed, trig an expansive reaction leading to an increase of volume whose entity depends on the chemical composition of the two starting components. It is possible to perform two kind of mission: 1) Not controlled removal: the two components are designed to react producing a low density, high expanded, spongy foam that incorporates the debris. The A/m ratio of the debris is increased and in this way also the ballistic parameter. As a consequence, the effect of

  8. Low-Quality Natural Gas Sulfur Removal/Recovery System

    SciTech Connect

    Lokhandwala, K.A.; Ringer, M.; Wijams, H.; Baker, R.W.

    1997-10-01

    Natural gas provides more than one-fifth of all the primary energy used in the United States. Much raw gas is `subquality`, that is, it exceeds the pipeline specifications for nitrogen, carbon dioxide, and/or hydrogen sulfide content, and much of this low-quality natural gas cannot be produced economically with present processing technology. Against this background, a number of industry-wide trends are affecting the natural gas industry. Despite the current low price of natural gas, long-term demand is expected to outstrip supply, requiring new gas fields to be developed. Several important consequences will result. First, gas fields not being used because of low-quality products will have to be tapped. In the future, the proportion of the gas supply that must be treated to remove impurities prior to delivery to the pipeline will increase substantially. The extent of treatment required to bring the gas up to specification will also increase. Gas Research Institute studies have shown that a substantial capital investment in facilities is likely to occur over the next decade. The estimated overall investment for all gas processing facilities up to the year 2000 alone is approximates $1.2 Billion, of which acid gas removal and sulfur recovery are a significant part in terms of invested capital. This large market size and the known shortcomings of conventional processing techniques will encourage development and commercialization of newer technologies such as membrane processes. Second, much of today`s gas production is from large, readily accessible fields. As new reserves are exploited, more gas will be produced from smaller fields in remote or offshore locations. The result is an increasing need for technology able to treat small-scale gas streams.

  9. [Evaluation of the binding affinity and RNA interference of low-molecular-weight chitosan/siRNA complexes using an imaging system].

    PubMed

    Kawaguchi, Yasuhisa; Okuda, Tomoyuki; Ban, Tatsunori; Danjo, Kazumi; Okamoto, Hirokazu

    2009-04-01

    Chitosan is one of the attractive non-viral carriers for gene delivery including siRNA. However, common chitosan, which has a relatively high molecular weight, is insoluble in water, which might make it difficult to apply clinically. In this study, we investigated the efficacy of low-molecular-weight chitosan (LMWC), which is soluble in water, as a carrier for siRNA delivery. To evaluate the binding affinity and RNA interference (RNAi) of LMWC/siRNA complexes, a multi-well imaging system (IVIS) was adapted. CT26 cells stably expressing firefly luciferase (CT26/Luc cells) were established to evaluate RNAi. Evaluation of RNAi using lipofectamine(TM) 2000 was carried out by employing a luminometer with cell lysis and IVIS without cell lysis. The results were closely correlated, suggesting the advantages of the multi-well imaging system regarding screening, the visualization of results, and nondestructive evaluation. Fluorescence generated by ethidium bromide intercalated in the double strand of siRNA was markedly quenched at a higher ratio of LMWC to siRNA (N/P) and lower pH. Evaluation of the particle size and zeta potential of LMWC/siRNA complexes also indicated the higher binding affinity of LMWC with siRNA. At N/P=300 and pH 6.5, which satisfied the high-level binding affinity of LMWC with siRNA, significantly lower luminescence was detected in CT26/Luc cells treated with LMWC/siRNA compared with those treated with LMWC alone, suggesting the presence of RNAi. These results suggested that LMWC may be an effective carrier for siRNA delivery, and that the multi-well imaging system may be a powerful tool to evaluate the binding affinity and RNAi.

  10. Peri-implant and systemic effects of high-/low-affinity bisphosphonate-hydroxyapatite composite coatings in a rabbit model with peri-implant high bone turnover

    PubMed Central

    2012-01-01

    Background Hydroxyapatite (HA) coatings composed with bisphosphonates (BPs) which have high mineral-binding affinities have been confirmed to successfully enhance implant stability. However, few previous studies focused on HA coatings composed with low-affinity BPs or on systemic effects of locally released BPs. Methods In this long-term study, we developed two kinds of BP-HA composite coatings using either high-affinity BP (alendronate, ALN) or low-affinity BP (risedronate, RIS). Thirty-six rabbits were divided into three groups according to different coating applications (group I: HA, group II: ALN-HA, and group III: RIS-HA). Implants were inserted into the proximal region of the medullary cavity of the left tibiay. At insertion, 2 × 108 wear particles were injected around implants to induce a peri-implant high bone turnover environment. Both local (left tibias) and systemic (right tibias and lumbar vertebrae) inhibitory effect on bone resorption were compared, including bone-implant integration, bone architecture, bone mineral density (BMD), implant stability, and serum levels of bone turnover markers. Results The results indicated that ALN-HA composite coating, which could induce higher bone-implant contact (BIC) ratio, bone mass augmentation, BMD, and implant stability in the peri-implant region, was more potent on peri-implant bone, while RIS-HA composite coating, which had significant systemic effect, was more potent on non-peri-implant bone, especially lumbar vertebrae. Conclusions It is instructive and meaningful to further clinical studies that we could choose different BP-HA composite coatings according to the patient’s condition. PMID:22686414

  11. EMERGING TECHNOLOGY BULLETIN: A CROSS-FLOW PERVAPORATION SYSTEM FOR REMOVAL OF VOCS FROM CONTAMINATED WASTEWATER

    EPA Science Inventory

    Pervaporation is a process for removing volatile organic compounds (VOC) from contaminated water. The performance of the cross-flow pervaporation system increases with temperature, with an equipment limitation of 35 degrees Celsius. Permeable membranes that preferentially adsor...

  12. ETV REPORT: REMOVAL OF ARSENIC IN DRINKING WATER - PALL CORPORATION MICROZA. MICROFILTRATION SYSTEM

    EPA Science Inventory

    Verification testing of the Pall Corporation Microza. Microfiltration System for arsenic removal was conducted at the Oakland County Drain Commissioner (OCDC) Plum Creek Development well station located in Oakland County, Michigan from August 19 through October 8, 2004. The sourc...

  13. Passive decay heat removal system for water-cooled nuclear reactors

    DOEpatents

    Forsberg, Charles W.

    1991-01-01

    A passive decay-heat removal system for a water-cooled nuclear reactor employs a closed heat transfer loop having heat-exchanging coils inside an open-topped, insulated box located inside the reactor vessel, below its normal water level, in communication with a condenser located outside of containment and exposed to the atmosphere. The heat transfer loop is located such that the evaporator is in a position where, when the water level drops in the reactor, it will become exposed to steam. Vapor produced in the evaporator passes upward to the condenser above the normal water level. In operation, condensation in the condenser removes heat from the system, and the condensed liquid is returned to the evaporator. The system is disposed such that during normal reactor operations where the water level is at its usual position, very little heat will be removed from the system, but during emergency, low water level conditions, substantial amounts of decay heat will be removed.

  14. Fish Assemblage Response to a Small Dam Removal in the Eightmile River System, Connecticut, USA

    NASA Astrophysics Data System (ADS)

    Poulos, Helen M.; Miller, Kate E.; Kraczkowski, Michelle L.; Welchel, Adam W.; Heineman, Ross; Chernoff, Barry

    2014-11-01

    We examined the effects of the Zemko Dam removal on the Eightmile River system in Salem, Connecticut, USA. The objective of this research was to quantify spatiotemporal variation in fish community composition in response to small dam removal. We sampled fish abundance over a 6-year period (2005-2010) to quantify changes in fish assemblages prior to dam removal, during drawdown, and for three years following dam removal. Fish population dynamics were examined above the dam, below the dam, and at two reference sites by indicator species analysis, mixed models, non-metric multidimensional scaling, and analysis of similarity. We observed significant shifts in fish relative abundance over time in response to dam removal. Changes in fish species composition were variable, and they occurred within 1 year of drawdown. A complete shift from lentic to lotic fishes failed to occur within 3 years after the dam was removed. However, we did observe increases in fluvial and transition (i.e., pool head, pool tail, or run) specialist fishes both upstream and downstream from the former dam site. Our results demonstrate the importance of dam removal for restoring river connectivity for fish movement. While the long-term effects of dam removal remain uncertain, we conclude that dam removals can have positive benefits on fish assemblages by enhancing river connectivity and fluvial habitat availability.

  15. Fish assemblage response to a small dam removal in the Eightmile River system, Connecticut, USA.

    PubMed

    Poulos, Helen M; Miller, Kate E; Kraczkowski, Michelle L; Welchel, Adam W; Heineman, Ross; Chernoff, Barry

    2014-11-01

    We examined the effects of the Zemko Dam removal on the Eightmile River system in Salem, Connecticut, USA. The objective of this research was to quantify spatiotemporal variation in fish community composition in response to small dam removal. We sampled fish abundance over a 6-year period (2005-2010) to quantify changes in fish assemblages prior to dam removal, during drawdown, and for three years following dam removal. Fish population dynamics were examined above the dam, below the dam, and at two reference sites by indicator species analysis, mixed models, non-metric multidimensional scaling, and analysis of similarity. We observed significant shifts in fish relative abundance over time in response to dam removal. Changes in fish species composition were variable, and they occurred within 1 year of drawdown. A complete shift from lentic to lotic fishes failed to occur within 3 years after the dam was removed. However, we did observe increases in fluvial and transition (i.e., pool head, pool tail, or run) specialist fishes both upstream and downstream from the former dam site. Our results demonstrate the importance of dam removal for restoring river connectivity for fish movement. While the long-term effects of dam removal remain uncertain, we conclude that dam removals can have positive benefits on fish assemblages by enhancing river connectivity and fluvial habitat availability.

  16. Structure of classical affine and classical affine fractional W-algebras

    SciTech Connect

    Suh, Uhi Rinn

    2015-01-15

    We introduce a classical BRST complex (See Definition 3.2.) and show that one can construct a classical affine W-algebra via the complex. This definition clarifies that classical affine W-algebras can be considered as quasi-classical limits of quantum affine W-algebras. We also give a definition of a classical affine fractional W-algebra as a Poisson vertex algebra. As in the classical affine case, a classical affine fractional W-algebra has two compatible λ-brackets and is isomorphic to an algebra of differential polynomials as a differential algebra. When a classical affine fractional W-algebra is associated to a minimal nilpotent, we describe explicit forms of free generators and compute λ-brackets between them. Provided some assumptions on a classical affine fractional W-algebra, we find an infinite sequence of integrable systems related to the algebra, using the generalized Drinfel’d and Sokolov reduction.

  17. Prioritizing removal of dams for passage of diadromous fishes on a major river system

    USGS Publications Warehouse

    Kocovsky, P.M.; Ross, R.M.; Dropkin, D.S.

    2009-01-01

    Native diadromous fishes have been extirpated from much of the Susquehanna River system for nearly a century. Recent restoration efforts have focused on removal of dams, but there are hundreds of dams and presently there is no biologically based system to assist in prioritizing their removal. We present a new method that uses existing habitat suitability index models (HSI) for American shad Alosa sapidissima, alewife A. pseudoharengus, blueback herring A. aestivalis, and American eel Anguilla rostrata to prioritize the removal of non-hydropower dams within the Susquehanna River system. We ranked HSI scores for each of the four species, association between a landscape-scale factor and HSIs, length of river opened by removing a dam, and distance from the mouth at Chesapeake Bay for each dam and then calculated a mean rank prioritization for dam removal by averaging the ranks for the seven criteria. This prioritization method is resistant to outliers, is not strongly affected by somewhat arbitrary decisions on metrics included in the analysis, and provides a biologically based prioritization for dam removal that can be easily amended to include other metrics or adapted to other river systems and that complements other social and economic considerations that must be included in decisions to remove dams.

  18. [Possibilities and limitations of Caridex System as an alternative to conventional caries removal].

    PubMed

    Scheutzel, P

    1989-08-01

    Exclusive use of chemo-mechanical Caridex-Caries removal system allows only in a few cases sufficient removal of caries. In histological investigation 108 of 120 cavities (90%) treated with the Caridex-system showed residual caries. In 92 cavities (77%) remaining bacteria could be observed. Whereas if combination of Caridex and spoon excavator was used in 25% respectively 23% a better caries removal as in case of using a spoon-excavator alone respectively a round bur was obtained. Scanning microscope examination of cavity wall after treatment with Caridex showed an increased roughness of the dentin surface. Therefore a superior shear bond strength of bonding and composite materials can be expected.

  19. Water treatment process and system for metals removal using Saccharomyces cerevisiae

    DOEpatents

    Krauter, Paula A. W.; Krauter, Gordon W.

    2002-01-01

    A process and a system for removal of metals from ground water or from soil by bioreducing or bioaccumulating the metals using metal tolerant microorganisms Saccharomyces cerevisiae. Saccharomyces cerevisiae is tolerant to the metals, able to bioreduce the metals to the less toxic state and to accumulate them. The process and the system is useful for removal or substantial reduction of levels of chromium, molybdenum, cobalt, zinc, nickel, calcium, strontium, mercury and copper in water.

  20. Arsenic Removal from Drinking Water Small Systems Research

    EPA Science Inventory

    This Power Point presentation will summarize some of the results from Arsenic Demonstration Program with the main focus on the adsorptive media systems used by small systems. The presentation will also describe the results of recent regeneration studies conducted on the arsenic ...

  1. Options for transpiration water removal in a crop growth system under zero gravity conditions

    NASA Technical Reports Server (NTRS)

    Blackwell, C. C.; Kliss, M.; Yendler, B.; Borchers, B.; Yendler, Boris S.; Nguyen, Thoi K.; Waleh, Ahmad

    1991-01-01

    The operation of a microgravity crop-growth system is a critical feature of NASA's Closed Ecological Life Support System (CELSS) development program. Transpiration-evolved water must be removed from the air that is recirculated in such a system, perhaps supplying potable water in the process. The present consideration of candidate systems for CELSS water removal gives attention to energy considerations and to a mechanical, inertial-operation water-separation system that was chosen due to the depth of current understanding of its operation.

  2. Robotized system for removal of slime from the bottom of steam generators

    NASA Astrophysics Data System (ADS)

    Kucherenko, O. V.; Shvarov, V. A.

    2014-02-01

    Reliability of steam generators depends not only on the main technical characteristics and correctness of the operational mode but also on the cleanliness of the heat-exchange surface and the presence of slime precipitated on the bottom. To provide the cleanliness, chemical methods of cleaning the heatexchange surfaces are used. In this article, we consider the process of removal of sediments that are formed precisely on the bottom of the steam generator from its volume. Possible mechanical methods for removal of sediments are presented. The consideration of variants of cleaning approved for acting steam generators showed the efficiency and applicability of the developed installation for the slime removal from steam generators. The main principles of construction of the system for slime removal from the steam generator bottom and constructive features of the installation, which make it possible to implement the stated tasks on the slime removal from the steam generator bottom, are given.

  3. Removal of a mixture of pesticides by a Streptomyces consortium: Influence of different soil systems.

    PubMed

    Fuentes, María S; Raimondo, Enzo E; Amoroso, María J; Benimeli, Claudia S

    2017-04-01

    Although the use of organochlorine pesticides (OPs) is restricted or banned in most countries, they continue posing environmental and health concerns, so it is imperative to develop methods for removing them from the environment. This work is aimed to investigate the simultaneous removal of three OPs (lindane, chlordane and methoxychlor) from diverse types of systems by employing a native Streptomyces consortium. In liquid systems, a satisfactory microbial growth was observed accompanied by removal of lindane (40.4%), methoxychlor (99.5%) and chlordane (99.8%). In sterile soil microcosms, the consortium was able to grow without significant differences in the different textured soils (clay silty loam, sandy and loam), both contaminated or not contaminated with the OPs-mixture. The Streptomyces consortium was able to remove all the OPs in sterile soil microcosm (removal order: clay silty loam > loam > sandy). So, clay silty loam soil (CSLS) was selected for next assays. In non-sterile CSLS microcosms, chlordane removal was only about 5%, nonetheless, higher rates was observed for lindane (11%) and methoxychlor (20%). In CSLS slurries, the consortium exhibited similar growth levels, in the presence of or in the absence of the OPs-mixture. Not all pesticides were removed in the same way; the order of pesticide dissipation was: methoxychlor (26%)>lindane (12.5%)>chlordane (10%). The outlines of microbial growth and pesticides removal provide information about using actinobacteria consortium as strategies for bioremediation of OPs-mixture in diverse soil systems. Texture of soils and assay conditions (sterility, slurry formulation) were determining factors influencing the removal of each pesticide of the mixture.

  4. Full System Modeling and Validation of the Carbon Dioxide Removal Assembly

    NASA Technical Reports Server (NTRS)

    Coker, Robert; Knox, James; Gauto, Hernando; Gomez, Carlos

    2014-01-01

    The Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project was initiated in September of 2011 as part of the Advanced Exploration Systems (AES) program. Under the ARREM project, testing of sub-scale and full-scale systems has been combined with multiphysics computer simulations for evaluation and optimization of subsystem approaches. In particular, this paper describes the testing and modeling of various subsystems of the carbon dioxide removal assembly (CDRA). The goal is a full system predictive model of CDRA to guide system optimization and development. The development of the CO2 removal and associated air-drying subsystem hardware under the ARREM project is discussed in a companion paper.

  5. Contaminant removal and hydraulic conductivity of laboratory rain garden systems for stormwater treatment.

    PubMed

    Good, J F; O'Sullivan, A D; Wicke, D; Cochrane, T A

    2012-01-01

    In order to evaluate the influence of substrate composition on stormwater treatment and hydraulic effectiveness, mesocosm-scale (180 L, 0.17 m(2)) laboratory rain gardens were established. Saturated (constant head) hydraulic conductivity was determined before and after contaminant (Cu, Zn, Pb and nutrients) removal experiments on three rain garden systems with various proportions of organic topsoil. The system with only topsoil had the lowest saturated hydraulic conductivity (160-164 mm/h) and poorest metal removal efficiency (Cu ≤ 69.0% and Zn ≤ 71.4%). Systems with sand and a sand-topsoil mix demonstrated good metal removal (Cu up to 83.3%, Zn up to 94.5%, Pb up to 97.3%) with adequate hydraulic conductivity (sand: 800-805 mm/h, sand-topsoil: 290-302 mm/h). Total metal amounts in the effluent were <50% of influent amounts for all experiments, with the exception of Cu removal in the topsoil-only system, which was negligible due to high dissolved fraction. Metal removal was greater when effluent pH was elevated (up to 7.38) provided by the calcareous sand in two of the systems, whereas the topsoil-only system lacked an alkaline source. Organic topsoil, a typical component in rain garden systems, influenced pH, resulting in poorer treatment due to higher dissolved metal fractions.

  6. Removal of an acid fume system contaminated with perchlorates located within hot cell

    SciTech Connect

    Rosenberg, K.E.; Henslee, S.P.; Vroman, W.R.; Krsul, J.R.; Michelbacher, J.A.; Knighton, G.C.

    1992-09-01

    An add scrubbing system located within the confines of a highly radioactive hot cell at Argonne National Laboratory-West (ANL-W) was remotely removed. The acid scrubbing system was routinely used for the dissolution of irradiated reactor fuel samples and structural materials. Perchloric acid was one of the acids used in the dissolution process and remained in the system with its inherent risks. Personnel could not enter the hot cell to perform the dismantling of the acid scabbing system due to the high radiation field and the explosion potential associated with the perchlorates. A robot was designed and built at ANL-W and used to dismantle the system without the need for personnel entry into the hot cell. The robot was also used for size reduction of removed components and loading of the removed components into waste containers.

  7. Evidence that the DNA mismatch repair system removes 1-nucleotide Okazaki fragment flaps.

    PubMed

    Kadyrova, Lyudmila Y; Dahal, Basanta K; Kadyrov, Farid A

    2015-10-02

    The DNA mismatch repair (MMR) system plays a major role in promoting genome stability and suppressing carcinogenesis. In this work, we investigated whether the MMR system is involved in Okazaki fragment maturation. We found that in the yeast Saccharomyces cerevisiae, the MMR system and the flap endonuclease Rad27 act in overlapping pathways that protect the nuclear genome from 1-bp insertions. In addition, we determined that purified yeast and human MutSα proteins recognize 1-nucleotide DNA and RNA flaps. In reconstituted human systems, MutSα, proliferating cell nuclear antigen, and replication factor C activate MutLα endonuclease to remove the flaps. ATPase and endonuclease mutants of MutLα are defective in the flap removal. These results suggest that the MMR system contributes to the removal of 1-nucleotide Okazaki fragment flaps.

  8. Jet pump-drive system for heat removal

    NASA Technical Reports Server (NTRS)

    French, James R. (Inventor)

    1987-01-01

    The invention does away with the necessity of moving parts such as a check valve in a nuclear reactor cooling system. Instead, a jet pump, in combination with a TEMP, is employed to assure safe cooling of a nuclear reactor after shutdown. A main flow exists for a reactor coolant. A point of withdrawal is provided for a secondary flow. A TEMP, responsive to the heat from said coolant in the secondary flow path, automatically pumps said withdrawn coolant to a higher pressure and thus higher velocity compared to the main flow. The high velocity coolant is applied as a driver flow for the jet pump which has a main flow chamber located in the main flow circulation pump. Upon nuclear shutdown and loss of power for the main reactor pumping system, the TEMP/jet pump combination continues to boost the coolant flow in the direction it is already circulating. During the decay time for the nuclear reactor, the jet pump keeps running until the coolant temperature drops to a lower and safe temperature where the heat is no longer a problem. At this lower temperature, the TEMP/jet pump combination ceases its circulation boosting operation. When the nuclear reactor is restarted and the coolant again exceeds the lower temperature setting, the TEMP/jet pump automatically resumes operation. The TEMP/jet pump combination is thus automatic, self-regulating and provides an emergency pumping system free of moving parts.

  9. Time dependence of NO{sub x} removal rate by a corona radical shower system

    SciTech Connect

    Ohkubo, Toshikazu; Kanazawa, Seiji; Nomoto, Yukiharu; Adachi, Takayoshi; Chang, J.S.

    1996-09-01

    In this paper, the effects of the flue gas flow rate and seed gas on the dynamics of corona discharge current-voltage characteristics and NO{sub x} removal characteristics are experimentally investigated for a corona radical shower system. The corona discharge current-voltage characteristics have two operating modes which have a significant influence on NO{sub x} removal characteristics, where the threshold value of the treatment gas to seed gas flow rate ratio is about 8. The hysteresis of corona current-voltage characteristics is observed in this system. For longer operational time, corona current and NO{sub x} removal rate significantly changes with time. When the operation of the apparatus starts at relatively low applied voltage, the corona current under constant applied voltage increases with time to reach a maximum value, then decreasing with time to reach a steady state. At this condition, high NO{sub x} removal efficiency can be achieved.

  10. Nitrogen removal and nitrate leaching for two perennial, sod-based forage systems receiving dairy effluent.

    PubMed

    Woodard, Kenneth R; French, Edwin C; Sweat, Lewin A; Graetz, Donald A; Sollenberger, Lynn E; Macoon, Bisoondat; Portier, Kenneth M; Rymph, Stuart J; Wade, Brett L; Prine, Gordon M; Van Horn, Harold H

    2003-01-01

    In northern Florida, year-round forage systems are used in dairy effluent sprayfields to reduce nitrate leaching. Our purpose was to quantify forage N removal and monitor nitrate N (NO3(-)-N) concentration below the rooting zone for two perennial, sod-based, triple-cropping systems over four 12-mo cycles (1996-2000). The soil is an excessively drained Kershaw sand (thermic, uncoated Typic Quartzip-samment). Effluent N rates were 500, 690, and 910 kg ha(-1) per cycle. Differences in N removal between a corn (Zea mays L.)-bermudagrass (Cynodon spp.)-rye (Secale cereale L.) system (CBR) and corn-perennial peanut (Arachis glabrata Benth.)-rye system (CPR) were primarily related to the performance of the perennial forages. Nitrogen removal of corn (125-170 kg ha(-1)) and rye (62-90 kg ha(-1)) was relatively stable between systems and among cycles. The greatest N removal was measured for CBR in the first cycle (408 kg ha(-1)), with the bermudagrass removing an average of 191 kg N ha(-1). In later cycles, N removal for bermudagrass declined because dry matter (DM) yield declined. Yield and N removal of perennial peanut increased over the four cycles. Nitrate N concentrations below the rooting zone were lower for CBR than CPR in the first two cycles, but differences were inconsistent in the latter two. The CBR system maintained low NO3(-)-N leaching in the first cycle when the bermudagrass was the most productive; however, it was not a sustainable system for long-term prevention of NO3(-)-N leaching due to declining bermudagrass yield in subsequent cycles. For CPR, effluent N rates > or = 500 kg ha(-1) yr(-1) have the potential to negatively affect ground water quality.

  11. Conformal field theory on affine Lie groups

    SciTech Connect

    Clubok, Kenneth Sherman

    1996-04-01

    Working directly on affine Lie groups, we construct several new formulations of the WZW model, the gauged WZW model, and the generic affine-Virasoro action. In one formulation each of these conformal field theories (CFTs) is expressed as a one-dimensional mechanical system whose variables are coordinates on the affine Lie group. When written in terms of the affine group element, this formulation exhibits a two-dimensional WZW term. In another formulation each CFT is written as a two-dimensional field theory, with a three- dimensional WZW term, whose fields are coordinates on the affine group. On the basis of these equivalent formulations, we develop a translation dictionary in which the new formulations on the affine Lie group are understood as mode formulations of the conventional formulations on the Lie group. Using this dictionary, we also express each CFT as a three-dimensional field theory on the Lie group with a four-dimensional WZW term. 36 refs.

  12. Jet pump-drive system for heat removal

    NASA Technical Reports Server (NTRS)

    French, J. R. (Inventor)

    1985-01-01

    A jet pump, in combination with a TEMP, is employed to assure safe cooling of a nuclear reactor after shutdown. A TEMP, responsive to the heat from the coolant in the secondary flow path, automatically pumps the withdrawn coolant to a higher pressure and thus higher velocity compared to the main flow. The high velocity coolant is applied as a driver flow for the jet pump which has a main flow chamber located in the main flow circulation pump. Upon nuclear shutdown and loss of power for the main reactor pumping system, the TEMP/jet pump combination continues to boost the coolant flow in the direction it is already circulating. During the decay time for the nuclear reactor, the jet pump keeps running until the coolant temperature drops to a lower and safe temperature. At this lower temperature, the TEMP/jet jump combination ceases its circulation boosting operation. The TEMP/jet pump combination is automatic, self-regulating and provides an emergency pumping system free of moving parts.

  13. K Basins sludge removal temporary sludge storage tank system

    SciTech Connect

    Mclean, M.A.

    1997-06-12

    Shipment of sludge from the K Basins to a disposal site is now targeted for August 2000. The current path forward for sludge disposal is shipment to Tank AW-105 in the Tank Waste Remediation System (TWRS). Significant issues of the feasibility of this path exist primarily due to criticality concerns and the presence of polychlorinated biphenyls (PCBS) in the sludge at levels that trigger regulation under the Toxic Substance Control Act. Introduction of PCBs into the TWRS processes could potentially involve significant design and operational impacts to both the Spent Nuclear Fuel and TWRS projects if technical and regulatory issues related to PCB treatment cannot be satisfactorily resolved. Concerns of meeting the TWRS acceptance criteria have evolved such that new storage tanks for the K Basins sludge may be the best option for storage prior to vitrification of the sludge. A reconunendation for the final disposition of the sludge is scheduled for June 30, 1997. To support this decision process, this project was developed. This project provides a preconceptual design package including preconceptual designs and cost estimates for the temporary sludge storage tanks. Development of cost estimates for the design and construction of sludge storage systems is required to help evaluate a recommendation for the final disposition of the K Basin sludge.

  14. Alternate particle removal technologies for the Airborne Activity Confinement System at the Savannah River Site

    SciTech Connect

    Brockmann, J.E.; Adkins, C.L.J.; Gelbard, F.

    1991-09-01

    This report presents a review of the filtration technologies available for the removal of particulate material from a gas stream. It was undertaken to identify alternate filtration technologies that may be employed in the Airborne Activity Confinement System (AACS) at the Savannah River Plant. This report is organized into six sections: (1) a discussion of the aerosol source term and its definition, (2) a short discussion of particle and gaseous contaminant removal mechanisms, (3) a brief overview of particle removal technologies, (4) a discussion of the existing AACS and its potential shortcomings, (5) an enumeration of issues to be addressed in upgrading the AACS, and, (6) a detailed discussion of the identified technologies. The purpose of this report is to identity available options to the existing particle removal system. This system is in continuous operation during routine operation of the reactor. As will be seen, there are a number of options and the selection of any technology or combination of technologies will depend on the design aerosol source term (yet to be appropriately defined) as well as the flow requirements and configuration. This report does not select a specific technology. It focuses on particulate removal and qualitatively on the removal of radio-iodine and mist elimination. Candidate technologies have been selected from industrial and nuclear gas cleaning applications.

  15. Hydrologic and pollutant removal performance of stormwater biofiltration systems at the field scale

    NASA Astrophysics Data System (ADS)

    Hatt, Belinda E.; Fletcher, Tim D.; Deletic, Ana

    2009-02-01

    SummaryBiofiltration systems are a recommended and increasingly popular technology for stormwater management; however there is a general lack of performance data for these systems, particularly at the field scale. The objective of this study was to investigate the hydrologic and pollutant removal performance of three field-scale biofiltration systems in two different climates. Biofilters were shown to effectively attenuate peak runoff flow rates by at least 80%. Performance assessment of a lined biofilter demonstrated that retention of inflow volumes by the filter media, for subsequent loss via evapotranspiration, reduced runoff volumes by 33% on average. Retention of water was found to be most influenced by inflow volumes, although only small to medium storms could be assessed. Vegetation was shown to be important for maintaining hydraulic capacity, because root growth and senescence countered compaction and clogging. Suspended solids and heavy metals were effectively removed, irrespective of the design configuration, with load reductions generally in excess of 90%. In contrast, nutrient retention was variable, and ranged from consistent leaching to effective and reliable removal, depending on the design. To ensure effective removal of phosphorus, a filter medium with a low phosphorus content should be selected. Nitrogen is more difficult to remove because it is highly soluble and strongly influenced by the variable wetting and drying regime that is inherent in biofilter operation. The results of this research suggest that reconfiguration of biofilter design to manage the deleterious effects of drying on biological activity is necessary to ensure long term nitrogen removal.

  16. Mullerian inhibiting substance fractionation by dye affinity chromatography.

    PubMed

    Budzik, G P; Powell, S M; Kamagata, S; Donahoe, P K

    1983-08-01

    Mullerian inhibiting substance (MIS), a large glycoprotein secreted by the fetal and neonatal testis, is responsible for regression of the Mullerian ducts in the male embryo. This fetal growth regulator has been purified more than 2000-fold from crude testicular incubation medium following fractionation on a triazinyl dye affinity support. A high yield of 60% recovered activity was achieved in the absence of exogenous carrier protein by stabilizing MIS with 2-mercaptoethanol, EDTA, and Nonidet-P40 and eliminating losses in the handling and concentration of MIS fractions. Although affinity elution with nucleotides has proved successful in other systems, MIS could not be eluted with ATP, GTP, or AMP, with or without divalent metal ions. Nucleotide elution, however, does remove contaminating proteins prior to MIS recovery with high ionic strength. The 2000-fold-purified MIS fraction, although not homogeneous, shows a reduction-sensitive band after SDS-gel electrophoresis that has been proposed to be the MIS dimer.

  17. Apparatus and method for removing solvent from carbon dioxide in resin recycling system

    DOEpatents

    Bohnert, George W.; Hand, Thomas E.; DeLaurentiis, Gary M.

    2009-01-06

    A two-step resin recycling system and method solvent that produces essentially contaminant-free synthetic resin material. The system and method includes one or more solvent wash vessels to expose resin particles to a solvent, the solvent contacting the resin particles in the one or more solvent wash vessels to substantially remove contaminants on the resin particles. A separator is provided to separate the solvent from the resin particles after removal from the one or more solvent wash vessels. The resin particles are next exposed to carbon dioxide in a closed loop carbon dioxide system. The closed loop system includes a carbon dioxide vessel where the carbon dioxide is exposed to the resin, substantially removing any residual solvent remaining on the resin particles after separation. A separation vessel is also provided to separate the solvent from the solvent laden carbon dioxide. Both the carbon dioxide and the solvent are reused after separation in the separation vessel.

  18. Development of design information for molecular-sieve type regenerative CO2-removal systems

    NASA Technical Reports Server (NTRS)

    Wright, R. M.; Ruder, J. M.; Dunn, V. B.; Hwang, K. C.

    1973-01-01

    Experimental and analytic studies were conducted with molecular sieve sorbents to provide basic design information, and to develop a system design technique for regenerable CO2-removal systems for manned spacecraft. Single sorbate equilibrium data were obtained over a wide range of conditions for CO2, water, nitrogen, and oxygen on several molecular sieve and silica gel sorbents. The coadsorption of CO2 with water preloads, and with oxygen and nitrogen was experimentally evaluated. Mass-transfer, and some limited heat-transfer performance evaluations were accomplished under representative operating conditions, including the coadsorption of CO2 and water. CO2-removal system performance prediction capability was derived.

  19. Cathode scraper system and method of using the same for removing uranium

    DOEpatents

    Williamson, Mark A; Wiedmeyer, Stanley G; Willit, James L; Barnes, Laurel A; Blaskovitz, Robert J

    2015-02-03

    Embodiments include a cathode scraper system and/or method of using the same for removing uranium. The cathode scraper system includes a plurality of cathode assemblies. Each cathode assembly includes a plurality of cathode rods. The cathode scraper system also includes a cathode scraper assembly configured to remove purified uranium deposited on the plurality of cathode rods. The cathode scraper assembly includes a plurality of scrapers arranged in a lattice, and each scraper of the plurality of scrapers is arranged to correspond to a different cathode rod.

  20. [Review on the main microorganisms and their metabolic mechanisms in enhanced biological phosphorus removal (EBPR) systems].

    PubMed

    Sun, Xue; Zhu, Wei-Jing; Wang, Liang; Wu, Wei-Xiang

    2014-03-01

    Enhanced biological phosphorus removal (EBPR) process is applied widely for removing phosphorus from wastewater. Studies on functional microorganisms and their metabolic mechanisms are fundamental to effective regulation for stable operation and performance improvement of EBPR process. Two main types of microorganisms in EBPR systems, polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) were selected to summarize their metabolic mechanisms such as substrate uptake mechanisms, glycogen degradation pathways, extent of TCA cycle involvement and metabolic similarity between PAOs and GAOs. Application of molecular biology techniques in microbiology and metabolic mechanisms involved in the EBPR system was evaluated. Potential future research areas for the EBPR system and process optimization were also proposed.

  1. Nuclear reactor with makeup water assist from residual heat removal system

    DOEpatents

    Corletti, Michael M.; Schulz, Terry L.

    1993-01-01

    A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit from an in-containment refueling water supply during staged depressurization leading up to passive emergency cooling by gravity feed from the refueling water storage tank, and flooding of the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and prevents flooding of the containment when such action is not necessary. Operation of the passive cooling system is not impaired. A high pressure makeup water storage tank is coupled to the reactor coolant circuit, holding makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal pumps move water from the refueling water storage tank into the coolant circuit as the coolant circuit is depressurized, preventing reaching the final depressurization stage unless the makeup coolant level continues to drop. The residual heat removal system can also be coupled in a loop with the refueling water supply tank, for an auxiliary heat removal path.

  2. Nuclear reactor with makeup water assist from residual heat removal system

    DOEpatents

    Corletti, M.M.; Schulz, T.L.

    1993-12-07

    A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit from an in-containment refueling water supply during staged depressurization leading up to passive emergency cooling by gravity feed from the refueling water storage tank, and flooding of the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and prevents flooding of the containment when such action is not necessary. Operation of the passive cooling system is not impaired. A high pressure makeup water storage tank is coupled to the reactor coolant circuit, holding makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal pumps move water from the refueling water storage tank into the coolant circuit as the coolant circuit is depressurized, preventing reaching the final depressurization stage unless the makeup coolant level continues to drop. The residual heat removal system can also be coupled in a loop with the refueling water supply tank, for an auxiliary heat removal path. 2 figures.

  3. Mathematical modeling based evaluation and simulation of boron removal in bioelectrochemical systems.

    PubMed

    Ping, Qingyun; Abu-Reesh, Ibrahim M; He, Zhen

    2016-11-01

    Boron removal is an arising issue in desalination plants due to boron's toxicity. As an emerging treatment concept, bioelectrochemical systems (BES) can achieve potentially cost-effective boron removal by taking advantage of cathodic-produced alkali. Prior studies have demonstrated successful removal of boron in microbial desalination cells (MDCs) and microbial fuel cells (MFCs), both of which are representative BES. Herein, mathematical models were developed to further evaluate boron removal by different BES and understand the key operating factors. The models delivered very good prediction of the boron concentration in the MDC integrated with Donnan Dialysis (DD) system with the lowest relative root-mean-square error (RMSE) of 0.00%; the predication of the MFC performance generated the highest RMSE of 18.55%. The model results of salt concentration, solution pH, and current generation were well fitted with experimental data for RMSE values mostly below 10%. The long term simulation of the MDC-DD system suggests that the accumulation of salt in the catholyte/stripping solution could have a positive impact on the removal of boron due to osmosis-driven convection. The current generation in the MDC may have little influence on the boron removal, while in the MFC the current-driven electromigration can contribute up to 40% of boron removal. Osmosis-induced convection transport of boron could be the major driving force for boron removal to a low level <2mgL(-1). The ratio between the anolyte and the catholyte flow rates should be kept >22.2 in order to avoid boron accumulation in the anolyte effluent.

  4. Defective removal of ribonucleotides from DNA promotes systemic autoimmunity

    PubMed Central

    Günther, Claudia; Kind, Barbara; Reijns, Martin A.M.; Berndt, Nicole; Martinez-Bueno, Manuel; Wolf, Christine; Tüngler, Victoria; Chara, Osvaldo; Lee, Young Ae; Hübner, Norbert; Bicknell, Louise; Blum, Sophia; Krug, Claudia; Schmidt, Franziska; Kretschmer, Stefanie; Koss, Sarah; Astell, Katy R.; Ramantani, Georgia; Bauerfeind, Anja; Morris, David L.; Cunninghame Graham, Deborah S.; Bubeck, Doryen; Leitch, Andrea; Ralston, Stuart H.; Blackburn, Elizabeth A.; Gahr, Manfred; Witte, Torsten; Vyse, Timothy J.; Melchers, Inga; Mangold, Elisabeth; Nöthen, Markus M.; Aringer, Martin; Kuhn, Annegret; Lüthke, Kirsten; Unger, Leonore; Bley, Annette; Lorenzi, Alice; Isaacs, John D.; Alexopoulou, Dimitra; Conrad, Karsten; Dahl, Andreas; Roers, Axel; Alarcon-Riquelme, Marta E.; Jackson, Andrew P.; Lee-Kirsch, Min Ae

    2014-01-01

    Genome integrity is continuously challenged by the DNA damage that arises during normal cell metabolism. Biallelic mutations in the genes encoding the genome surveillance enzyme ribonuclease H2 (RNase H2) cause Aicardi-Goutières syndrome (AGS), a pediatric disorder that shares features with the autoimmune disease systemic lupus erythematosus (SLE). Here we determined that heterozygous parents of AGS patients exhibit an intermediate autoimmune phenotype and demonstrated a genetic association between rare RNASEH2 sequence variants and SLE. Evaluation of patient cells revealed that SLE- and AGS-associated mutations impair RNase H2 function and result in accumulation of ribonucleotides in genomic DNA. The ensuing chronic low level of DNA damage triggered a DNA damage response characterized by constitutive p53 phosphorylation and senescence. Patient fibroblasts exhibited constitutive upregulation of IFN-stimulated genes and an enhanced type I IFN response to the immunostimulatory nucleic acid polyinosinic:polycytidylic acid and UV light irradiation, linking RNase H2 deficiency to potentiation of innate immune signaling. Moreover, UV-induced cyclobutane pyrimidine dimer formation was markedly enhanced in ribonucleotide-containing DNA, providing a mechanism for photosensitivity in RNase H2–associated SLE. Collectively, our findings implicate RNase H2 in the pathogenesis of SLE and suggest a role of DNA damage–associated pathways in the initiation of autoimmunity. PMID:25500883

  5. Development of Carbon Dioxide Removal Systems for Advanced Exploration Systems 2014-2015

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Coker, Robert; Huff, Timothy L.; Gatens, Robyn; Miller, Lee A.; Stanley, Christine

    2015-01-01

    A long-term goal for NASA is to enable crewed missions to Mars: first to the vicinity of Mars, and then to the Mars surface. These missions present new challenges for all aspects of spacecraft design in comparison with the International Space Station, as resupply is unavailable in the transit phase, and early return is not possible. Additionally, mass, power, and volume must be minimized for all phases to reduce propulsion needs. Mass reduction is particularly crucial for Mars surface landing and liftoff due to the challenges inherent in these operations for even much smaller payloads. In this paper we describe current and planned developments in the area of carbon dioxide removal to support future crewed Mars missions. Activities are also described that apply to both the resolution of anomalies observed in the ISS CDRA and the design of life support systems for future missions.

  6. Development of Carbon Dioxide Removal Systems for Advanced Exploration Systems 2015-2016

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Coker, Robert; Howard, David; Peters, Warren; Watson, David; Cmarik, Gregory; Miller, Lee A.

    2016-01-01

    A long-term goal for NASA is to enable crewed missions to Mars: first to the vicinity of Mars, and then to the Mars surface. These missions present new challenges for all aspects of spacecraft design in comparison with the International Space Station, as resupply is unavailable in the transit phase, and early return is not possible. Additionally, mass, power, and volume must be minimized for all phases to reduce propulsion needs. Mass reduction is particularly crucial for Mars surface landing and liftoff due to the challenges inherent in these operations for even much smaller payloads. In this paper we describe current and planned developments in the area of carbon dioxide removal to support future crewed Mars missions. Activities are also described that apply to both the resolution of anomalies observed in the ISS CDRA and the design of life support systems for future missions.

  7. Solvent cleaning system and method for removing contaminants from solvent used in resin recycling

    DOEpatents

    Bohnert, George W.; Hand, Thomas E.; DeLaurentiis, Gary M.

    2009-01-06

    A two step solvent and carbon dioxide based system that produces essentially contaminant-free synthetic resin material and which further includes a solvent cleaning system for periodically removing the contaminants from the solvent so that the solvent can be reused and the contaminants can be collected and safely discarded in an environmentally safe manner.

  8. Removal of NOx and CO from a burner system.

    PubMed

    Jaafar, Mohammad Nazri Mohd; Ishak, Mohd Shaiful Ashrul; Saharin, Sanisah

    2010-04-15

    This paper presents the development of an emissions-controlling technique for oil burners aimed especially to reduce oxides of nitrogen (NOx). Another emission of interest is carbon monoxide (CO). In this research, a liquid fuel burner is used. In the first part, five different radial air swirler blade angles, 30 degrees , 40 degrees , 45 degrees , 50 degrees , and 60 degrees , respectively, have been investigated using a combustor with 163 mm inside diameter and 280 mm length. Tests were conducted using kerosene as fuel. Fuel was injected at the back plate of the swirler outlet. The swirler blade angles and equivalence ratios were varied. A NOx reduction of more than 28% and CO emissions reduction of more than 40% were achieved for blade angle of 60 degrees compared to the 30 degrees blade angle. The second part of this paper presents the insertion of an orifice plate at the exit plane of the air swirler outlet. Three different orifice plate diameters of 35, 40, and 45 mm were used with a 45 degrees radial air swirler vane angle. The fuel flow rates and orifice plate's sizes were varied. NOx reduction of more than 30% and CO emissions reduction of more than 25% were obtained using the 25 mm diameter orifice plate compared to the test configuration without the orifice plate. The last part of this paper presents tests conducted using the air-staging method. An industrial oil burner system was investigated using the air staging method in order to reduce emission, especially NOx. Emissions reduction of 30% and 16.7% were obtained for NOx and CO emissions, respectively, when using air staging compared to the non-air-staging tests.

  9. Manned Mission Planning Considerations when Using a Non-Regenerable CO2 Removal System

    NASA Technical Reports Server (NTRS)

    DeSimpelaere, Edward

    2011-01-01

    As the commercial spacecraft industry increases in size, there will be a corresponding increase in the number of manned spacecraft built and operationally flown each year. Industry teams for these new spacecraft will have multiple design and operational choices to make for each of these spacecraft s subsystems. The carbon dioxide (CO2) removal subsystem of the environmental control and life support system is one that presents such challenges. This paper seeks to aid industry in making design and operations choices by providing a document containing lessons learned by the Space Shuttle Program s Operations team, with specific focus given to the non-regenerable CO2 removal system currently used by the Space Shuttle. Carbon dioxide, one of the key byproducts of respiration, can lead to injury and death if allowed to build up in a spacecraft s habitable environment. Therefore, any spacecraft s environmental control and life support system must contain a method for removing this hazard. These removal systems can either be non-regenerable or regenerable. While this paper defines the difference between these types and presents a generic comparison of their capabilities, the focus is specifically on the Space Shuttle s CO2 removal systems. This will include a short discussion of the Space Shuttle s regenerable amine solid absorption system that was part of the Extended Duration Orbiter (EDO) modification, however, emphasis is given to the non-regenerable Lithium Hydroxide canister system used as the prime removal method employed by the Space Shuttle, including a discussion on why this method was chosen over a regenerable system. A full exposition is given on all of the considerations required for mission planning when using a non-regenerable CO2 removal system. Key discussion items include: airflow lessons learned, recent physiological issues related to short term and long term exposure and how lower levels may be more harmful than previously thought, lithium hydroxide

  10. An analytical fuzzy-based approach to ?-gain optimal control of input-affine nonlinear systems using Newton-type algorithm

    NASA Astrophysics Data System (ADS)

    Milic, Vladimir; Kasac, Josip; Novakovic, Branko

    2015-10-01

    This paper is concerned with ?-gain optimisation of input-affine nonlinear systems controlled by analytic fuzzy logic system. Unlike the conventional fuzzy-based strategies, the non-conventional analytic fuzzy control method does not require an explicit fuzzy rule base. As the first contribution of this paper, we prove, by using the Stone-Weierstrass theorem, that the proposed fuzzy system without rule base is universal approximator. The second contribution of this paper is an algorithm for solving a finite-horizon minimax problem for ?-gain optimisation. The proposed algorithm consists of recursive chain rule for first- and second-order derivatives, Newton's method, multi-step Adams method and automatic differentiation. Finally, the results of this paper are evaluated on a second-order nonlinear system.

  11. CO2 Removal and Atmosphere Revitalization Systems for Next Generation Space Flight

    NASA Technical Reports Server (NTRS)

    Luna, Bernadette; Mulloth, Lila M.; Varghese, Mini M.; Hogan, John Andrew

    2010-01-01

    Removal of metabolic CO2 from breathing air is a vital process for life support in all crewed space missions. A CO2 removal processor called the Low Power CO2 Removal (LPCOR) system is being developed in the Bioengineering Branch at NASA Ames Research Center. LPCOR utilizes advanced adsorption and membrane gas separation processes to achieve substantial power and mass reduction when compared to the state-of-the-art carbon dioxide removal assembly (CORA) of the US segment of the International Space Station (ISS). LPCOR is an attractive alternative for use in commercial spacecraft for short-duration missions and can easily be adapted for closed-loop life support applications. NASA envisions a next-generation closed-loop atmosphere revitalization system that integrates advanced CO2 removal, O2 recovery, and trace contaminant control processes to improve overall system efficiency. LPCOR will serve as the front end to such a system. LPCOR is a reliable air revitalization technology that can serve both the near-term and long-term human space flight needs of NASA and its commercial partners.

  12. Effect of operational cycle time length on nitrogen removal in an alternating oxidation ditch system.

    PubMed

    Mantziaras, I D; Stamou, A; Katsiri, A

    2011-06-01

    This paper refers to nitrogen removal optimization of an alternating oxidation ditch system through the use of a mathematical model and pilot testing. The pilot system where measurements have been made has a total volume of 120 m(3) and consists of two ditches operating in four phases during one cycle and performs carbon oxidation, nitrification, denitrification and settling. The mathematical model consists of one-dimensional mass balance (convection-dispersion) equations based on the IAWPRC ASM 1 model. After the calibration and verification of the model, simulation system performance was made. Optimization is achieved by testing operational cycles and phases with different time lengths. The limits of EU directive 91/271 for nitrogen removal have been used for comparison. The findings show that operational cycles with smaller time lengths can achieve higher nitrogen removals and that an "equilibrium" between phase time percentages in the whole cycle, for a given inflow, must be achieved.

  13. Porphyrin π-stacking in a heme protein scaffold tunes gas ligand affinity.

    PubMed

    Weinert, Emily E; Phillips-Piro, Christine M; Marletta, Michael A

    2013-10-01

    The role of π-stacking in controlling redox and ligand binding properties of porphyrins has been of interest for many years. The recent discovery of H-NOX domains has provided a model system to investigate the role of porphyrin π-stacking within a heme protein scaffold. Removal of a phenylalanine-porphyrin π-stack dramatically increased O2, NO, and CO affinities and caused changes in redox potential (~40mV) without any structural changes. These results suggest that small changes in redox potential affect ligand affinity and that π-stacking may provide a novel route to engineer heme protein properties for new functions.

  14. Demonstration [sic] of a System for Removing Malachite Green : Final Report.

    SciTech Connect

    Marking, Leif L.

    1989-04-01

    Activated carbon has been used effectively to remove tastes, odors, and contaminants from public water supplies. The adsorption efficiency is influenced by the size of carbon granules, flow rate, column depth, and retention time. A study was designed to (1) determine the type of filter and kind of carbon that was most efficient and (2) demonstrate that carbon filters can be used to remove malachite green from water used for egg incubation or to hold adult salmon before spawning. Minicolumn simulation studies showed that 8 /times/ 30 mesh granular carbon manufactured from bituminous coal was effective for continuously removing malachite green from water for 230 days at a flow rate of 500 gpm and for 62 days at a flow rate of 1000 gpm. The removal capacity at the slower flow rate was 69 mg of malachite green per gram of carbon. A filter system that contained 20,000 pounds of activated carbon in each of two chambers was effective for removal of malachite green from treated water in adult salmon holding ponds at flows of 500 gpm and greater. The removal efficiency was 99.8% after 105 hours of operation, and the adsorption capacity of the system was projected to be 20 or more years of routine hatchery operation. A filter system that contained 2000 pounds of activated carbon in each of two chambers was effective for removal of malachite green from treated water in salmon egg incubation units at the designated flow rate of 50 gpm and also at faster flow rates. 14 refs., 5 figs., 6 tabs.

  15. Natural Organic Matter Removal and Fouling in a Low Pressure Hybrid Membrane Systems

    PubMed Central

    Uyak, Vedat; Akdagli, Muge; Cakmakci, Mehmet; Koyuncu, Ismail

    2014-01-01

    The objective of this study was to investigate powdered activated carbon (PAC) contribution to natural organic matter (NOM) removal by a submerged MF and UF hybrid systems. It was found that filtration of surface waters by a bare MF and UF membranes removed negligible TOC; by contrast, significant amounts of TOC were removed when daily added PAC particles were predeposited on the membrane surfaces. These results support the assumption that the membranes surface properties and PAC layer structure might have considerably influential factor on NOM removal. Moreover, it was concluded that the dominant removal mechanism of hybrid membrane system is adsorption of NOM within PAC layer rather than size exclusion of NOM by both of membrane pores. Transmembrane pressure (TMP) increases with PAC membrane systems support the view that PAC adsorption pretreatment will not prevent the development of membrane pressure; on the contrary, PAC particles themselves caused membrane fouling by blocking the entrance of pores of MF and UF membranes. Although all three source waters have similar HPI content, it appears that the PAC interaction with the entrance of membrane pores was responsible for offsetting the NOM fractional effects on membrane fouling for these source waters. PMID:24523651

  16. Removal of copper in an integrated sulfate reducing bioreactor-crystallization reactor system.

    PubMed

    Sierra-Alvarez, Reyes; Hollingsworth, Jeremy; Zhou, Michael S

    2007-02-15

    Removal of copper was investigated using an innovative water treatment system integrating a sulfidogenic bioreactor with a fluidized-bed crystallization reactor containing fine sand to facilitate the recovery of copper as a purified copper-sulfide mineral. The performance of the system was tested using a simulated semiconductor manufacturing wastewater containing high levels of Cu2+ (4-66 mg/L), sulfate, and a mixture of citrate, isopropanol, and polyethylene glycol (Mn 300). Soluble copper removal efficiencies exceeding 99% and effluent copper concentrations averaging 89 micog/L were demonstrated in the two-stage system, with near complete metal removal occurring in the crystallizer. Copper crystals deposited on sand grains were identified as covellite (CuS). The removal of organic constituents did not exceed 70% of the initial chemical oxygen demand due to incomplete degradation of isopropanol and its breakdown product (acetone). Taken as a whole, these results indicate the potential of this novel reactor configuration for the simultaneous removal of heavy metals and organic constituents. The ability of this process to recover heavy metals in a purified form makes it particularly attractive for the treatment of contaminated aqueous streams, including industrial wastewaters and acid mine drainage.

  17. A dielectric affinity microbiosensor

    NASA Astrophysics Data System (ADS)

    Huang, Xian; Li, Siqi; Schultz, Jerome S.; Wang, Qian; Lin, Qiao

    2010-01-01

    We present an affinity biosensing approach that exploits changes in dielectric properties of a polymer due to its specific, reversible binding with an analyte. The approach is demonstrated using a microsensor comprising a pair of thin-film capacitive electrodes sandwiching a solution of poly(acrylamide-ran-3-acrylamidophenylboronic acid), a synthetic polymer with specific affinity to glucose. Binding with glucose induces changes in the permittivity of the polymer, which can be measured capacitively for specific glucose detection, as confirmed by experimental results at physiologically relevant concentrations. The dielectric affinity biosensing approach holds the potential for practical applications such as long-term continuous glucose monitoring.

  18. Affinity in electrophoresis.

    PubMed

    Heegaard, Niels H H

    2009-06-01

    The journal Electrophoresis has greatly influenced my approaches to biomolecular affinity studies. The methods that I have chosen as my main tools to study interacting biomolecules--native gel and later capillary zone electrophoresis--have been the topic of numerous articles in Electrophoresis. Below, the role of the journal in the development and dissemination of these techniques and applications reviewed. Many exhaustive reviews on affinity electrophoresis and affinity CE have been published in the last few years and are not in any way replaced by the present deliberations that are focused on papers published by the journal.

  19. NN-adaptive output feedback tracking control for a class of discrete-time non-affine systems with a dynamic compensator

    NASA Astrophysics Data System (ADS)

    Zhang, Lijun; Zhao, Jiemei; Qi, Xue; Jia, Heming

    2013-06-01

    The problem of tracking control for a class of uncertain non-affine discrete-time nonlinear systems with internal dynamics is addressed. The fixed point theorem is first employed to ensure the control problem in question is solvable and well-defined. Based on it, an adaptive output feedback control scheme based on neural network (NN) is presented. The proposed control algorithm consists of two parts: a dynamic compensator is introduced to stabilise the linear portion of the tracking error system; a single-hidden-layer neural network (SHL NN) approximation mechanism is introduced to cancel the uncertainties resulting from the non-affine function, where the recursive weight update rules of NN estimation are derived from the discrete-time version of Lyapunov control theory. Ultimate boundedness of the error signals is shown through Lyapunov's direct method and the discrete-time version of input-to-state stability (ISS) theory. Finally, a model of automatical underwater vehicle (AUV) is considered to show the effectiveness of the proposed control scheme.

  20. Induction of the high-affinity Na(+)-dependent glutamate transport system XAG- by hypertonic stress in the renal epithelial cell line NBL-1.

    PubMed Central

    Ferrer-Martinez, A; Felipe, A; Nicholson, B; Casado, J; Pastor-Anglada, M; McGivan, J

    1995-01-01

    The high-affinity Na(+)-dependent glutamate transport system XAG- is induced (threefold increase in Vmax. with no change in Km) by hypertonicity in the renal epithelial cell line NBL-1. This effect is dependent on protein synthesis and glycosylation and is accompanied by an increase in EAAC1 mRNA levels. Other Na(+)-dependent transport systems in this cell line do not respond to hypertonic stress. In contrast to recent findings [Ruiz-Montasell, Gomez-Angelats, Casado, Felipe, McGivan and Pastor-Anglada (1994) Proc. Natl. Acad. Sci. U.S.A. 91, 9569-9573] showing that increased system A activity after hyperosmotic shock results from induction of a regulatory protein, this is the first demonstration that hypertonicity may increase the expression of the gene for an amino acid transport protein itself. Images Figure 4 PMID:7654212

  1. Removal of emerging contaminants from municipal wastewater with an integrated membrane system, MBR-RO.

    PubMed

    Dolar, Davor; Gros, Meritxell; Rodriguez-Mozaz, Sara; Moreno, Jordi; Comas, Joaquim; Rodriguez-Roda, Ignasi; Barceló, Damià

    2012-11-15

    The presence of emerging contaminants in the aquatic environment and their potential effects on living organisms has become an issue of growing concern. Among emerging contaminants, pharmaceuticals may enter the aquatic environment due to their high consumption and their incomplete removal in conventional municipal wastewater treatment plants (WWTPs). The main goal of this study was the assessment of the removal efficiency of pharmaceuticals found in municipal wastewater of a coastal WWTP (Castell-Platja d'Aro, Spain) using an integrated pilot scale membrane system (MBR-RO). Twenty multiple-class pharmaceuticals (including psychiatric drugs, macrolide antibiotics, β-blockers, sulfonamide and fluoroquinolone antibiotics, histamine H2 receptor antagonists, anti-inflammatories, nitroimidazole, β-agonist and antiplatelet agent) were measured in real influent with the lowest average concentration for psychiatric drugs (0.017 μg L(-1)) to the highest for macrolide antibiotics (2.02 μg L(-1)). Although some contaminants were in relatively high concentrations (even up to 2.90 μg L(-1) in the case of ofloxacin). The combination of MBR and RO treatment showed excellent overall removal of target emerging contaminants with removal rates above 99% for all of them. For some compounds (metronidazole, hydrocodone, codein, ranitidine) MBR provided high removal efficiency (up to 95%). Additionally RO membrane showed removal rates always higher than 99%.

  2. Removal of bacteria, protozoa and viruses through a multiple-barrier household water disinfection system.

    PubMed

    Espinosa-García, A C; Díaz-Ávalos, C; Solano-Ortiz, R; Tapia-Palacios, M A; Vázquez-Salvador, N; Espinosa-García, S; Sarmiento-Silva, R E; Mazari-Hiriart, M

    2014-03-01

    Municipal water disinfection systems in some areas are not always able to meet water consumer needs, such as ensuring distributed water quality, because household water management can be a contributing factor in water re-contamination. This fact is related to the storage options that are common in places where water is scarce or is distributed over limited time periods. The aim of this study is to assess the removal capacity of a multiple-barrier water disinfection device for protozoa, bacteria, and viruses. Water samples were taken from households in Mexico City and spiked with a known amount of protozoa (Giardia cyst, Cryptosporidium oocyst), bacteria (Escherichia coli), and viruses (rotavirus, adenovirus, F-specific ribonucleic acid (FRNA) coliphage). Each inoculated sample was processed through a multiple-barrier device. The efficiency of the multiple-barrier device to remove E. coli was close to 100%, and more than 87% of Cryptosporidium oocysts and more than 98% of Giardia cysts were removed. Close to 100% of coliphages were removed, 99.6% of the adenovirus was removed, and the rotavirus was almost totally removed. An effect of site by zone was detected; this observation is important because the water characteristics could indicate the efficiency of the multiple-barrier disinfection device.

  3. Nitrate removal from groundwater driven by electricity generation and heterotrophic denitrification in a bioelectrochemical system.

    PubMed

    Tong, Yiran; He, Zhen

    2013-11-15

    This research aims to develop a new approach for in situ nitrate removal from groundwater by using a bioelectrochemical system (BES). The BES employs bioelectricity generated from organic compounds to drive nitrate moving from groundwater into the anode and reduces nitrate to nitrogen gas by heterotrophic denitrification. This laboratory study of a bench-scale BES demonstrated effective nitrate removal from both synthetic and actual groundwater. It was found that applying an electrical potential improved the nitrate removal and the highest nitrate removal rate of 208.2 ± 13.3g NO3(-)-Nm(-3) d(-1) was achieved at 0.8 V. Although the open circuit condition (no electricity generation) still resulted in a nitrate removal rate of 158.5 ± 4.2 gm(-3) d(-1) due to ion exchange, electricity production could inhibit ion exchange and prevent introducing other undesired ions into groundwater. The nitrate removal rate exhibited a linear relationship with the initial nitrate concentration in groundwater. The BES produced a higher current density of 33.4 Am(-3) and a higher total coulomb of 244.7 ± 9.1C from the actual groundwater than the synthetic groundwater, likely because other ions in the actual groundwater promoted ion movement to assist electricity generation. Further development of this BES will need to address several key challenges in anode feeding solution, ion competition, and long-term stability.

  4. Cyclic electrowinning/precipitation (CEP) system for the removal of heavy metal mixtures from aqueous solutions

    PubMed Central

    Grimshaw, Pengpeng; Calo, Joseph M.; Hradil, George

    2011-01-01

    The description and operation of a novel cyclic electrowinning/precipitation (CEP) system for the simultaneous removal of mixtures of heavy metals from aqueous solutions are presented. CEP combines the advantages of electrowinning in a spouted particulate electrode (SPE) with that of chemical precipitation and redissolution, to remove heavy metals at low concentrations as solid metal deposits on particulate cathode particles without exporting toxic metal precipitate sludges from the process. The overall result is very large volume reduction of the heavy metal contaminants as a solid metal deposit on particles that can either be safely discarded as such, or further processed to recover particular metals. The performance of this system is demonstrated with data on the removal of mixtures of copper, nickel, and cadmium from aqueous solutions. PMID:22102792

  5. Bicarbonate-form anion exchange: affinity, regeneration, and stoichiometry.

    PubMed

    Rokicki, Christopher A; Boyer, Treavor H

    2011-01-01

    Magnetic ion exchange (MIEX) is an effective process for removing dissolved organic carbon (DOC) from natural waters, but its implementation has been limited due to production of waste sodium chloride solution (i.e., brine) from the regeneration process. Chloride is of concern because elevated concentrations can have adverse effects on engineered and natural systems. The goal of this research was to explore the efficacy of using anion exchange resin with bicarbonate as the mobile counter ion, which would produce a non-chloride regeneration solution. It was found that bicarbonate-form MIEX resin had a similar affinity as chloride-form MIEX resin for sulfate, nitrate, DOC, and ultraviolet-absorbing substances. Both bicarbonate-form and chloride-form MIEX resins showed the greatest removal efficiencies as fresh resin, and removal efficiency decreased with multiple regeneration cycles. Nevertheless, sodium bicarbonate solution was as effective as sodium chloride solution at regenerating MIEX resin. Regeneration of the bicarbonate-form MIEX resin was illustrated by sparging carbon dioxide gas in a water/resin slurry. This regeneration process would eliminate the need for the addition of salts such as sodium chloride or sodium bicarbonate. The stoichiometry of the bicarbonate-form resin revealed that the bicarbonate was deprotonating within the resin matrix leading to a mixture of both carbonate and bicarbonate mobile counter ions. This work makes an important contribution to ion exchange applications for water treatment by evaluating the affinity, regeneration, and stoichiometry of bicarbonate-form anion exchange.

  6. Development of a carbon filter system for removing malachite green from hatchery effluents

    SciTech Connect

    Marking, L.L. ); Leith, D. ); Davis, J. )

    1990-04-01

    The US Fish and Wildlife Service was granted an investigational New Animal Drug permit by the US Food and Drug Administration for the use of malachite green as a fungicide at selected state and federal fish hatcheries. However, the permit required that the fungicide be removed from all treated water after March 1989. A study was designed to (1) determine the type of filter and kind of carbon that was most efficient for removal of malachite green and (2) demonstrate that carbon filters can be used to remove malachite green from water used for egg incubation or to hold adult salmon before spawning. Minicolumn simulation studies showed that 8 {times} 30-mesh granular carbon was effective for continuously removing malachite green from water for 230 d at a flow rate of 500 gal/min and for only 62 d at a flow rate of 1,000 gal/min. The removal capacity at the slower flow rate was 1.1 oz of malachite green per pound of carbon. A filter system that contained 20,000 lb of activated carbon in each of two chambers was effective for removal of malachite green from treated water in adult salmon holding ponds at flows of 500 gal/min (6.4 gal/min per ft{sup 2}) and greater. The removal efficiency was 99.8% after 105 h of operation, and the adsorption capacity of the system was projected to be sufficient for 20 or more years of routine hatchery operation. A filter system that contained 2,000 lb of activated carbon in each of two chambers was effective for removal of malachite green from treated water in salmon egg incubation units at the designated flow rate of 50 gal/min (4.0 gal/min per ft{sup 2}) and also at faster flow rates. Removal efficiency decreased only slightly for faster flows in both filter systems, and the efficiency improved when treated water was passed through two filter chambers in series.

  7. The yeast Aft2 transcription factor determines selenite toxicity by controlling the low affinity phosphate transport system

    PubMed Central

    Pérez-Sampietro, María; Serra-Cardona, Albert; Canadell, David; Casas, Celia; Ariño, Joaquín; Herrero, Enrique

    2016-01-01

    The yeast Saccharomyces cerevisiae is employed as a model to study the cellular mechanisms of toxicity and defense against selenite, the most frequent environmental selenium form. We show that yeast cells lacking Aft2, a transcription factor that together with Aft1 regulates iron homeostasis, are highly sensitive to selenite but, in contrast to aft1 mutants, this is not rescued by iron supplementation. The absence of Aft2 strongly potentiates the transcriptional responses to selenite, particularly for DNA damage- and oxidative stress-responsive genes, and results in intracellular hyperaccumulation of selenium. Overexpression of PHO4, the transcriptional activator of the PHO regulon under low phosphate conditions, partially reverses sensitivity and hyperaccumulation of selenite in a way that requires the presence of Spl2, a Pho4-controlled protein responsible for post-transcriptional downregulation of the low-affinity phosphate transporters Pho87 and Pho90. SPL2 expression is strongly downregulated in aft2 cells, especially upon selenite treatment. Selenite hypersensitivity of aft2 cells is fully rescued by deletion of PHO90, suggesting a major role for Pho90 in selenite uptake. We propose that the absence of Aft2 leads to enhanced Pho90 function, involving both Spl2-dependent and independent events and resulting in selenite hyperaccumulation and toxicity. PMID:27618952

  8. Miniaturized reaction vessel system, method for performing site-specific biochemical reactions and affinity fractionation for use in DNA sequencing

    DOEpatents

    Mirzabekov, Andrei Darievich; Lysov, Yuri Petrovich; Dubley, Svetlana A.

    2000-01-01

    A method for fractionating and sequencing DNA via affinity interaction is provided comprising contacting cleaved DNA to a first array of oligonucleotide molecules to facilitate hybridization between said cleaved DNA and the molecules; extracting the hybridized DNA from the molecules; contacting said extracted hybridized DNA with a second array of oligonucleotide molecules, wherein the oligonucleotide molecules in the second array have specified base sequences that are complementary to said extracted hybridized DNA; and attaching labeled DNA to the second array of oligonucleotide molecules, wherein the labeled re-hybridized DNA have sequences that are complementary to the oligomers. The invention further provides a method for performing multi-step conversions of the chemical structure of compounds comprising supplying an array of polyacrylamide vessels separated by hydrophobic surfaces; immobilizing a plurality of reactants, such as enzymes, in the vessels so that each vessel contains one reactant; contacting the compounds to each of the vessels in a predetermined sequence and for a sufficient time to convert the compounds to a desired state; and isolating the converted compounds from said array.

  9. Ammonium nitrogen removal from wastewater with a three-dimensional electrochemical oxidation system.

    PubMed

    Ding, Jing; Zhao, Qing-Liang; Wei, Liang-Liang; Chen, Yang; Shu, Xin

    2013-01-01

    Ammonium-containing wastewater could cause the promotion of eutrophication and a hindrance to the disinfection of water supplies. In this study, the feasibility of removing low-concentration ammonium nitrogen from synthetic and real wastewater by electrochemical oxidation was investigated. Using laboratory-scale electrochemical systems, the effects of chloride concentration, current density, anode materials, cathode materials, electrode gap, initial ammonium concentration and three-dimensional particles on the removal of ammonium nitrogen and current efficiency (CE) were evaluated. Ammonium nitrogen removal was mainly dependent upon anode materials and current density. The performance of two- and three-dimensional electrochemical oxidation systems was comparatively discussed. Both particle electrodes could enhance ammonium nitrogen removal and increase CE. However, the mechanism of the process seemed to be different. Moreover, the interaction of zeolites adsorption and electrochemical oxidation on the anode in a three-dimensional system could favor the regeneration of zeolites. Surface morphology of the used Ru-Ir-Sn/Ti anode revealed its longer working life of electrocatalysis. The result of ammonium degradation for a real wastewater treatment plant effluent showed the degradation rates in a three-dimensional system increased by 1.4 times those in a two-dimensional system.

  10. Affine dynamics with torsion

    NASA Astrophysics Data System (ADS)

    Gültekin, Kemal

    2016-03-01

    In this study, we give a thorough analysis of a general affine gravity with torsion. After a brief exposition of the affine gravities considered by Eddington and Schrödinger, we construct and analyze different affine gravities based on the determinants of the Ricci tensor, the torsion tensor, the Riemann tensor, and their combinations. In each case we reduce equations of motion to their simplest forms and give a detailed analysis of their solutions. Our analyses lead to the construction of the affine connection in terms of the curvature and torsion tensors. Our solutions of the dynamical equations show that the curvature tensors at different points are correlated via non-local, exponential rescaling factors determined by the torsion tensor.

  11. Lectin affinity electrophoresis.

    PubMed

    Kobayashi, Yuka

    2014-01-01

    An interaction or a binding event typically changes the electrophoretic properties of a molecule. Affinity electrophoresis methods detect changes in the electrophoretic pattern of molecules (mainly macromolecules) that occur as a result of biospecific interactions or complex formation. Lectin affinity electrophoresis is a very effective method for the detection and analysis of trace amounts of glycobiological substances. It is particularly useful for isolating and separating the glycoisomers of target molecules. Here, we describe a sensitive technique for the detection of glycoproteins separated by agarose gel-lectin affinity electrophoresis that uses antibody-affinity blotting. The technique is tested using α-fetoprotein with lectin (Lens culinaris agglutinin and Phaseolus vulgaris agglutinin)-agarose gels.

  12. Dissolved nutrients and atrazine removal by column-scale monophasic and biphasic rain garden model systems.

    PubMed

    Yang, Hanbae; McCoy, Edward L; Grewal, Parwinder S; Dick, Warren A

    2010-08-01

    Rain gardens are bioretention systems that have the potential to reduce peak runoff flow and improve water quality in a natural and aesthetically pleasing manner. We compared hydraulic performance and removal efficiencies of nutrients and atrazine in a monophasic rain garden design versus a biphasic design at a column-scale using simulated runoff. The biphasic rain garden was designed to increase retention time and removal efficiency of runoff pollutants by creating a sequence of water saturated to unsaturated conditions. We also evaluated the effect of C substrate availability on pollutant removal efficiency in the biphasic rain garden. Five simulated runoff events with various concentrations of runoff pollutants (i.e. nitrate, phosphate, and atrazine) were applied to the monophasic and biphasic rain gardens once every 5d. Hydraulic performance was consistent over the five simulated runoff events. Peak flow was reduced by approximately 56% for the monophasic design and 80% for the biphasic design. Both rain garden systems showed excellent removal efficiency of phosphate (89-100%) and atrazine (84-100%). However, significantly (p<0.001) higher removal of nitrate was observed in the biphasic (42-63%) compared to the monophasic rain garden (29-39%). Addition of C substrate in the form of glucose increased removal efficiency of nitrate significantly (p<0.001), achieving up to 87% removal at a treatment C/N ratio of 2.0. This study demonstrates the importance of retention time, environmental conditions (i.e. saturated/unsaturated conditions), and availability of C substrate for bioremediation of pollutants, especially nitrates, in rain gardens.

  13. Plant traits that enhance pollutant removal from stormwater in biofiltration systems.

    PubMed

    Read, Jennifer; Fletcher, Tim D; Wevill, Tricia; Deletic, Ana

    2010-01-01

    Plants species have been shown to improve the performance of stormwater biofiltration systems, particularly in removal of N and P. Recent research has shown that plants vary in their contribution to pollutant removal but little is known about the type of plant that is best suited to use in biofilters in terms of survival, growth rate, and performance. In this study, growth responses of 20 species to applications of semi-synthetic stormwater were measured, and the roles of key plant traits in removal of N, P, and several metals were investigated. There was no evidence of negative effects of stormwater application on plant growth, and plant traits, particularly root traits, were strongly correlated negatively with N and P concentrations of effluent stormwater. The most common and strong contributors to N and P removal appeared to be the length of the longest root, rooting depth, total root length, and root mass. The plants that made the strongest contribution to pollutant removal, e.g, Carex appressa, combined these traits with high growth rates. Investigation of other plant traits (e.g, physiology), causal mechanisms, and effects of more complex planting environments (e.g, species mixtures) should further guide the selection of plants to enhance performance of biofiltration systems.

  14. Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

    SciTech Connect

    V.K. Konovalov; O.V. Yashkin; V.V. Ermakov

    2008-03-15

    A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered.

  15. BOA: Asbestos pipe-insulation removal robot system, Phase 2. Topical report, January--June 1995

    SciTech Connect

    Schempf, H.; Bares, J.E.

    1995-06-01

    This report explored the regulatory impact and cost-benefit of a robotic thermal asbestos pipe-insulation removal system over the current manual abatement work practice. The authors are currently in the second phase of a two-phase program to develop a robotic asbestos abatement system, comprised of a ground-based support system (including vacuum, fluid delivery, computing/electronics/power, and other subsystems) and several on-pipe removal units, each sized to handle pipes within a given diameter range. The intent of this study was to (i) aid in developing design and operational criteria for the overall system to maximize cost-efficiency, and (ii) to determine the commercial potential of a robotic pipe-insulation abatement system.

  16. Affinity partitioning of albumin and alpha-fetoprotein in an aqueous two-phase system using poly(ethylene glycol)-bound triazine dyes.

    PubMed

    Birkenmeier, G; Usbeck, E; Kopperschläger, G

    1984-01-01

    Human albumin and alpha-fetoprotein are partitioned in an aqueous two-phase system composed of 10% (w/w) Dextran and 7.5% (w/w) poly(ethylene glycol). When a small amount of poly(ethylene glycol) is replaced by Cibacron Blue F3G-A-liganded poly(ethylene glycol) the partition coefficient, K, of albumin increases by the factor of about 4000 whereas the K value of alpha-fetoprotein undergoes only a small change. The change of the partition coefficient in a logarithmic scale induced by increasing dye-polymer concentrations turned out as a useful measure for the affinity of albumin and alpha-fetoprotein to the dyes. The effect of pH and salt concentration on the affinity partition of albumin and alpha-fetoprotein is demonstrated. The partition of the two proteins in presence of Cibacron Blue F3G-A-liganded poly(ethylene glycol) is compared with seven other triazine dye-poly(ethylene glycol) derivatives.

  17. Passive decay heat removal system for water-cooled nuclear reactors

    SciTech Connect

    Forseberg, C.W.

    1990-01-01

    This document describes passive decay-heat removal system for a water-cooled nuclear reactor which employs a closed heat transfer loop having heat-exchanging coils inside an open-topped, insulated evaporator located inside the reactor vessel, below its normal water level, in communication with a condenser located outside of containment and exposed to the atmosphere. The heat transfer loop is located such that the evaporator is in a position where, when the water level drops in the reactor, it will become exposed to steam. Vapor produced in the evaporator passes upward to the condenser above the normal water level. In operation, condensation in the condenser removes heat from the system, and the condensed liquid is returned to the evaporator. The system is disposed such that during normal reactor operations where the water level is at its usual position, very little heat will be removed from the system, but during emergency, low water level conditions, substantial amounts of decay heat will be removed.

  18. Integrated nitrogen removal biofilter system with ceramic membrane for advanced post-treatment of municipal wastewater.

    PubMed

    Son, Dong-Jin; Yun, Chan-Young; Kim, Woo-Yeol; Zhang, Xing-Ya; Kim, Dae-Gun; Chang, Duk; Sunwoo, Young; Hong, Ki-Ho

    2016-12-01

    The pre-denitrification biofilm process for nitrogen removal was combined with ceramic membrane with pore sizes of 0.05-0.1 µm as a system for advanced post-treatment of municipal wastewater. The system was operated under an empty bed hydraulic retention time of 7.8 h, recirculation ratio of 3, and transmembrane pressure of 0.47 bar. The system showed average removals of organics, total nitrogen, and solids as high as 93%, 80%, and 100%, respectively. Rapid nitrification could be achieved and denitrification was performed in the anoxic filter without external carbon supplements. The residual particulate organics and nitrogen in effluent from biofilm process could be also removed successfully through membrane filtration and the removal of total coliform was noticeably improved after membrane filtration. Thus, a system composed of the pre-denitrification biofilm process with ceramic membrane would be a compact and flexible option for advanced post-treatment of municipal wastewater.

  19. History of SO2 removal system at the Meramec plant of union electric.

    PubMed

    Dreifke, G E; McLaughlin, J F; Smith, J D

    1975-01-01

    In line with the then emerging air pollution control regulations Union Electric installed a limestone injection wet scrubber sulfur dioxide removal system on an intermediate size coal-fired utility boiler at its Meramec Power Plant on an experimental basis in September, 1968. Approximately 3 years of operation many difficulties were encountered with plugging and scaling of various system components by calcium sulphate. As a result of this experience along with related experiences by other utilities employing similar systems, the experiment was terminated in June, 1971. As a result of the experiences gained, however, second generation experiments in sulfur dioxide removal have been initiated elsewhere with the hope of improved performance. A number of experimental projects are still under tests. Costs in resources, reliability, and disposal of residual by-products are matters of great concern. The ture cost of sulfur dioxide removal systems in dollars and resources is not well known and perhaps a reevaluation of current and future SO2 removal projects is in order at this time before additional resources are committed.

  20. URANIUM REMOVAL FROM DRINKING WATER USING A SMALL FULL-SCALE SYSTEM

    EPA Science Inventory

    This report presents background and history of water quality, the basis for design and nine months of actual operating data for a small, full-scale strong-base ion exchange system that is used to remove uranium from a water supply serving a school in Jefferson County, CO. Informa...

  1. Microbial community profile of a lead service line removed from a drinking water distribution system.

    PubMed

    White, Colin; Tancos, Matthew; Lytle, Darren A

    2011-08-01

    A corroded lead service line was removed from a drinking water distribution system, and the microbial community was profiled using 16S rRNA gene techniques. This is the first report of the characterization of a biofilm on the surface of a corroded lead drinking water service line. The majority of phylotypes have been linked to heavy-metal-contaminated environments.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  3. [Effect of magnesium ion content on the biological phosphorus removal system in SBR].

    PubMed

    Li, Xing; Gao, Da-Wen; Liu, Lin

    2011-07-01

    This study investigated the effect of magnesium iron content on the enhanced biological phosphorus removal system, which performed differently at magnesium content of 0 mg/L, 8 mg/L and 24 mg/L (R1-R3). The results indicated appropriate Mg addition could enrich phosphorus accumulating organisms and keep stable running. During the steady state period, phosphorus removal rate declined to below 50% gradually, moreover, the system tended to deteriorate with the shortage of magnesium in R1. However, the system with appropriate magnesium kept the higher phosphorus removal rate (more than 90%). The statistical analysis of the experimental data also showed a strong correlation between Mg and phosphorus concentrations in R2 and R3, the ratios of Mg and P were 0.29-0.59 and 0.25-0.54 in two reactors respectively. In the anaerobic phase of EBPR, the magnesium content, the absolute value of ORP and the phosphates release had a correlation. Meanwhile, magnesium was released together with phosphates in the anaerobic phase, and that would uptake under aerobic conditions. Thus it was obvious that magnesium played a key role on the biological phosphorus removal system.

  4. Microbial Community Profile of a Lead Service Line Removed from a Drinking Water Distribution System

    EPA Science Inventory

    A corroded lead water pipe was removed from a drinking water distribution system and the microbial community was profiled using 16S rDNA techniques. This is the first report of the characterization of biofilm on a surface of a corroded lead drinking water pipe. The majority of ...

  5. Capital and Operating Costs of Small Arsenic Removal Adsorptive Media Systems

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) conducted 50 full-scale demonstration projects on treatment systems removing arsenic from drinking water in 26 states throughout the U.S. The projects were conducted to evaluate the performance, reliability, and cost of arsenic remo...

  6. REMOVAL OF ARSENIC IN DRINKING WATER: ARS CFU-50 APC ELECTROFLOCCULATION AND FILTRATION WATER TREATMENT SYSTEM

    EPA Science Inventory

    ETV testing of the ARS CFU-50 APC Electroflocculation and Filtration Water Treatment System (ARS CFU-50 APC) for arsenic removal was conducted at the Town of Bernalillo Well #3 site from April 18 through May 2, 2006. The source water was chlorinated groundwater from two supply w...

  7. Protein Delivery System Containing a Nickel-Immobilized Polymer for Multimerization of Affinity-Purified His-Tagged Proteins Enhances Cytosolic Transfer.

    PubMed

    Postupalenko, Viktoriia; Desplancq, Dominique; Orlov, Igor; Arntz, Youri; Spehner, Danièle; Mely, Yves; Klaholz, Bruno P; Schultz, Patrick; Weiss, Etienne; Zuber, Guy

    2015-09-01

    Recombinant proteins with cytosolic or nuclear activities are emerging as tools for interfering with cellular functions. Because such tools rely on vehicles for crossing the plasma membrane we developed a protein delivery system consisting in the assembly of pyridylthiourea-grafted polyethylenimine (πPEI) with affinity-purified His-tagged proteins pre-organized onto a nickel-immobilized polymeric guide. The guide was prepared by functionalization of an ornithine polymer with nitrilotriacetic acid groups and shown to bind several His-tagged proteins. Superstructures were visualized by electron and atomic force microscopy using 2 nm His-tagged gold nanoparticles as probes. The whole system efficiently carried the green fluorescent protein, single-chain antibodies or caspase 3, into the cytosol of living cells. Transduction of the protease caspase 3 induced apoptosis in two cancer cell lines, demonstrating that this new protein delivery method could be used to interfere with cellular functions.

  8. Five year-round forage systems in a dairy effluent sprayfield: phosphorus removal.

    PubMed

    Woodard, Kenneth R; Sollenberger, Lynn E; Sweat, Lewin A; Graetz, Donald A; Rymph, Stuart J; Joo, Yongsung

    2007-01-01

    In northern Florida, forages are grown in dairy effluent sprayfields to recover excess P. Our purpose was to evaluate five year-round forage systems for their capacity to remove P from a dairy sprayfield. The soil is a Kershaw sand (thermic, uncoated Typic Quartzipsamment). Systems included bermudagrass (Cynodon spp.)-rye (Secale cereale L.) (BR), perennial peanut (Arachis glabrata Benth.)-rye (PR), corn (Zea mays L.)-forage sorghum [Sorghum bicolor (L.) Moench]-rye (CSR), corn-bermudagrass-rye (CBR), and corn-perennial peanut-rye (CPR). Forages were grown for five 12-mo cycles. Effluent P rates were 80, 120, and 165 kg ha-1 cycle-1. The 5-cycle P removal was 67 kg ha-1 cycle-1 for BR, 54 kg ha-1 for CBR, 52 kg for CSR, 45 kg for PR, and 43 for CPR. Removal of P by winter rye was low. There were differences in system rankings among cycles primarily due to changes in the performance of perennial forages. In the first two cycles, BR had the greatest P removal (91 kg ha-1 cycle-1) due to high bermudagrass yield and P concentration. In the first cycle, P removal was lowest for PR (36 kg ha-1) because perennial peanut was slow to establish. In later cycles, P removal for BR declined because bermudagrass yield and P concentration declined. It increased for PR because peanut yield increased. The yield of corn in CBR, CPR, and CSR was consistently high but P concentration was modest (avg. 2.2 g kg-1). Sorghum produced moderate but stable yield and had low P levels (avg. 1.8 g kg-1). Effluent rate marginally affected the performance of most grasses. For P recovery in dairy sprayfields in northern Florida, the best warm-season forage would likely be a high yielding, persistent bermudagrass.

  9. Numerical modeling analysis of VOC removal processes in different aerobic vertical flow systems for groundwater remediation.

    PubMed

    De Biase, Cecilia; Carminati, Andrea; Oswald, Sascha E; Thullner, Martin

    2013-11-01

    Vertical flow systems filled with porous medium have been shown to efficiently remove volatile organic contaminants (VOCs) from contaminated groundwater. To apply this semi-natural remediation strategy it is however necessary to distinguish between removal due to biodegradation and due to volatile losses to the atmosphere. Especially for (potentially) toxic VOCs, the latter needs to be minimized to limit atmospheric emissions. In this study, numerical simulation was used to investigate quantitatively the removal of volatile organic compounds in two pilot-scale water treatment systems: an unplanted vertical flow filter and a planted one, which could also be called a vertical flow constructed wetland, both used for the treatment of contaminated groundwater. These systems were intermittently loaded with contaminated water containing benzene and MTBE as main VOCs. The highly dynamic but permanently unsaturated conditions in the porous medium facilitated aerobic biodegradation but could lead to volatile emissions of the contaminants. Experimental data from porous material analyses, flow rate measurements, solute tracer and gas tracer test, as well as contaminant concentration measurements at the boundaries of the systems were used to constrain a numerical reactive transport modeling approach. Numerical simulations considered unsaturated water flow, transport of species in the aqueous and the gas phase as well as aerobic degradation processes, which made it possible to quantify the rates of biodegradation and volatile emissions and calculating their contribution to total contaminant removal. A range of degradation rates was determined using experimental results of both systems under two operation modes and validated by field data obtained at different operation modes applied to the filters. For both filters, simulations and experimental data point to high biodegradation rates, if the flow filters have had time to build up their removal capacity. For this case volatile

  10. Pre-Conceptual Design for Northstar ⁹⁹Mo Process Tritium Removal System

    SciTech Connect

    Nobile, Arthur; Reichert, Heidi; Hollis, William Kirk; Taylor, Craig Michael; Gordon, John Cameron; Dale, Gregory E.

    2016-01-12

    In this report we describe a preliminary concept for a Tritium Removal System (TRS) to remove tritium that is generated in the ⁹⁹Mo production process. Preliminary calculations have been performed to evaluate an approximate size for the system. The concept described utilizes well-established detritiation technology based on catalytic oxidation of tritium and tritiated hydrocarbons to water in a high temperature (400 °C) reactor and capture of water in a molecular sieve bed. The TRS concept involves use of a single system that would cycle through each of the seven online target systems and remove tritium that has been accumulated after one week’s run time. The TRS would perform cleanup operations on each target system for a period of approximately 24 hours. This would occur while the system is still online and just prior to target replacement, so tritium levels would at their minimum values for target replacement. In the concept, during normal operation a small fraction (1%) of the helium recirculating in the system would be diverted through the TRS and returned to the flow loop. With this approach sufficient levels of detritiation can be accomplished in a 24 hour period. In the study it was found that because of the need to maintain low oxygen levels in the system (<100 ppm) this increases the size of the catalytic reactor. As a result of this finding, consideration should be given to other methods for removing tritium from the system. Other methods such as catalytic exchange of tritium with an unsaturated organic compound and subsequent trapping on activated carbon or molecular sieve could offer advantages of reducing reactor size and operation at lower reactor temperature. However the most significant advantage of such an approach would be the ability to operate in very low oxygen environments, which would eliminate any concerns for oxidation of the target.

  11. Computer Simulation and Modeling of CO2 Removal Systems for Exploration 2013-2014

    NASA Technical Reports Server (NTRS)

    Coker, R.; Knox, J.; Gomez, C.

    2015-01-01

    The Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project was initiated in September of 2011 as part of the Advanced Exploration Systems (AES) program. Under the ARREM project and the follow-on Life Support Systems (LSS) project, testing of sub-scale and full-scale systems has been combined with multiphysics computer simulations for evaluation and optimization of subsystem approaches. In particular, this paper will describes the testing and 1-D modeling of the combined water desiccant and carbon dioxide sorbent subsystems of the carbon dioxide removal assembly (CDRA). The goal is a full system predictive model of CDRA to guide system optimization and development.

  12. Two Plant Bacteria, S. meliloti and Ca. Liberibacter asiaticus, Share Functional znuABC Homologues That Encode for a High Affinity Zinc Uptake System

    PubMed Central

    Vahling-Armstrong, Cheryl M.; Zhou, Huasong; Benyon, Lesley; Morgan, J. Kent; Duan, Yongping

    2012-01-01

    The Znu system, encoded for by znuABC, can be found in multiple genera of bacteria and has been shown to be responsible for the import of zinc under low zinc conditions. Although this high-affinity uptake system is known to be important for both growth and/or pathogenesis in bacteria, it has not been functionally characterized in a plant-associated bacterium. A single homologue of this system has been identified in the plant endosymbiont, Sinorhizobium meliloti, while two homologous systems were found in the destructive citrus pathogen, Candidatus Liberibacter asiaticus. To understand the role of these protein homologues, a complementation assay was devised allowing the individual genes that comprise the system to be assayed independently for their ability to reinstate a partially-inactivated Znu system. Results from the assays have demonstrated that although all of the genes from S. meliloti were able to restore activity, only one of the two Ca. Liberibacter asiaticus encoded gene clusters contained genes that were able to functionally complement the system. Additional analysis of the gene clusters reveals that distinct modes of regulation may also exist between the Ca. Liberibacter asiaticus and S. meliloti import systems despite the intracellular-plant niche common to both of these bacteria. PMID:22655039

  13. Removal of ammonia from urine vapor by a dual-catalyst system

    NASA Technical Reports Server (NTRS)

    Budininkas, P.

    1977-01-01

    The feasibility of removing ammonia from urine vapor by a low-temperature dual-catalyst system has been demonstrated. The process is based on the catalytic oxidation of ammonia to a mixture of nitrogen, nitrous oxide, and water, followed by a catalytic decomposition of the nitrous oxide into its elements. Potential ammonia oxidation and nitrous oxide decomposition catalysts were first screened with artificial gas mixtures, then tested with the actual urine vapor produced by boiling untreated urine. A suitable dual-catalyst bed arrangement was found that achieved the removal of ammonia and also organic carbon, and recovered water of good quality from urine vapor.

  14. Pilot scale test of a produced water-treatment system for initial removal of organic compounds

    SciTech Connect

    Sullivan, Enid J; Kwon, Soondong; Katz, Lynn; Kinney, Kerry

    2008-01-01

    A pilot-scale test to remove polar and non-polar organics from produced water was performed at a disposal facility in Farmington NM. We used surfactant-modified zeolite (SMZ) adsorbent beds and a membrane bioreactor (MBR) in combination to reduce the organic carbon content of produced water prior to reverse osmosis (RO). Reduction of total influent organic carbon (TOC) to 5 mg/L or less is desirable for efficient RO system operation. Most water disposed at the facility is from coal-bed gas production, with oil production waters intermixed. Up to 20 gal/d of produced water was cycled through two SMZ adsorbent units to remove volatile organic compounds (BTEX, acetone) and semivolatile organic compounds (e.g., napthalene). Output water from the SMZ units was sent to the MBR for removal of the organic acid component of TOC. Removal of inorganic (Mn and Fe oxide) particulates by the SMZ system was observed. The SMZ columns removed up to 40% of the influent TOC (600 mg/L). BTEX concentrations were reduced from the initial input of 70 mg/L to 5 mg/L by the SMZ and to an average of 2 mg/L after the MBR. Removal rates of acetate (input 120-170 mg/L) and TOC (input up to 45 mg/L) were up to 100% and 92%, respectively. The water pH rose from 8.5 to 8.8 following organic acid removal in the MBR; this relatively high pH was likely responsible for observed scaling of the MBR internal membrane. Additional laboratory studies showed the scaling can be reduced by metered addition of acid to reduce the pH. Significantly, organic removal in the MBR was accomplished with a very low biomass concentration of 1 g/L throughout the field trial. An earlier engineering evaluation shows produced water treatment by the SMZ/MBR/RO system would cost from $0.13 to $0.20 per bbl at up to 40 gpm. Current estimated disposal costs for produced water are $1.75 to $4.91 per bbl when transportation costs are included, with even higher rates in some regions. Our results suggest that treatment by an SMZ

  15. Cascade air-stripping system for removal of low and semi-volatile organic contaminants

    SciTech Connect

    Jang, Won.

    1989-01-01

    Many hazardous waste sites have been known to have groundwaters contaminated with low volatile, hazardous compounds such as bromoform 1,1,2,2-tetrachloroethane, 1,2-dibromo-3-chloropropane (DBCP), napthalene, and polychlorinated biphenyls (PCBs). In addition, a large number of public water supplies have been reported to have taste and odor problems in drinking water, which are attributed primarily to naturally occurring compounds, such as 2-methylisoborneol (MIB), geosmin, etc. These classes of compounds have very low Henry's Constant, H{sub c}, in the range of 1 to 50 atm. Air-stripping in countercurrent packed towers is a well accepted treatment process for removing volatile organic chemicals (VOCs) from water. The USEPA has identified packed countercurrent air-stripping as not only the least-cost, but also one of the best available technologies for the removal of VOCs. However, the economic viability of this process is limited to volatile compounds of H{sub c} value greater than SO atm. A novel modification of the conventional countercurrent air-stripping process, introduced as cascade air-stripping was proposed for cost effective removal of these classes of compounds from water and at hazardous waste spill-sites. The main objectives of this study were to demonstrate the concept of cascade air-stripping; to compare cascade air-stripping with conventional air-stripping under identical conditions; and to verify the hypothesis that the cascade system is superior to the conventional system at the pilot and prototype scales. Results of the pilot and prototype study showed that the cascade airstrip ping system was a viable and economical approach to remove low and semi-volatile organic compounds from water. The cascade system consistently showed higher removals than the conventional system for both pilot and prototype scale study.

  16. The Gas-Cooled Fast Reactor: Report on Safety System Design for Decay Heat Removal

    SciTech Connect

    K. D. Weaver; T. Marshall; T. Y. C. Wei; E. E. Feldman; M. J. Driscoll; H. Ludewig

    2003-09-01

    The gas-cooled fast reactor (GFR) was chosen as one of the Generation IV nuclear reactor systems to be developed based on its excellent potential for sustainability through reduction of the volume and radiotoxicity of both its own fuel and other spent nuclear fuel, and for extending/utilizing uranium resources orders of magnitude beyond what the current open fuel cycle can realize. In addition, energy conversion at high thermal efficiency is possible with the current designs being considered, thus increasing the economic benefit of the GFR. However, research and development challenges include the ability to use passive decay heat removal systems during accident conditions, survivability of fuels and in-core materials under extreme temperatures and radiation, and economical and efficient fuel cycle processes. This report addresses/discusses the decay heat removal options available to the GFR, and the current solutions. While it is possible to design a GFR with complete passive safety (i.e., reliance solely on conductive and radiative heat transfer for decay heat removal), it has been shown that the low power density results in unacceptable fuel cycle costs for the GFR. However, increasing power density results in higher decay heat rates, and the attendant temperature increase in the fuel and core. Use of active movers, or blowers/fans, is possible during accident conditions, which only requires 3% of nominal flow to remove the decay heat. Unfortunately, this requires reliance on active systems. In order to incorporate passive systems, innovative designs have been studied, and a mix of passive and active systems appears to meet the requirements for decay heat removal during accident conditions.

  17. Design Strategies and Preliminary Prototype for a Low-Cost Arsenic Removal System for Rural Bangladesh

    SciTech Connect

    Mathieu, Johanna L.; Gadgil, Ashok J.; Kowolik, Kristin; Qazi, Shefah; Agogino, Alice M.

    2009-09-14

    Researchers have invented a material called ARUBA -- Arsenic Removal Using Bottom Ash -- that effectively and affordably removes arsenic from Bangladesh groundwater. Through analysis of studies across a range of disciplines, observations, and informal interviews conducted over three trips to Bangladesh, we have applied mechanical engineering design methodology to develop eight key design strategies, which were used in the development of a low-cost, community-scale water treatment system that uses ARUBA to removearsenic from drinking water. We have constructed, tested, and analysed a scale version of the system. Experiments have shown that the system is capable of reducing high levels of arsenic (nearly 600 ppb) to below the Bangladesh standard of 50 ppb, while remaining affordable to people living on less than US$2/day. The system could be sustainably implemented as a public-private partnership in rural Bangladesh.

  18. Sorbent Structural Impacts Due to Humidity on Carbon Dioxide Removal Sorbents for Advanced Exploration Systems

    NASA Technical Reports Server (NTRS)

    Watson, David; Knox, James C.; West, Phillip; Stanley, Christine M.; Bush, Richard

    2015-01-01

    The Life Support Systems Project (LSSP) under the Advanced Exploration Systems (AES) program builds upon the work performed under the AES Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project focusing on the numerous technology development areas. The CO2 removal and associated air drying development efforts are focused on improving the current state-of-the-art system on the International Space Station (ISS) utilizing fixed beds of sorbent pellets by seeking more robust pelletized sorbents, evaluating structured sorbents, and examining alternate bed configurations to improve system efficiency and reliability. A component of the CO2 removal effort encompasses structural stability testing of existing and emerging sorbents. Testing will be performed on dry sorbents and sorbents that have been conditioned to three humidity levels. This paper describes the sorbent structural stability screening efforts in support of the LSS Project within the AES Program.

  19. The ability of biologically based wastewater treatment systems to remove emerging organic contaminants--a review.

    PubMed

    Garcia-Rodríguez, Aida; Matamoros, Víctor; Fontàs, Clàudia; Salvadó, Victòria

    2014-10-01

    Biologically based wastewater treatment systems are considered a sustainable, cost-effective alternative to conventional wastewater treatment systems. These systems have been used and studied for the treatment of urban sewage from small communities, and recently, it has been reported that they can also effectively remove emerging organic contaminants (EOCs). EOCs are a new group of unregulated contaminants which include pharmaceutical and personal care products, some pesticides, veterinary products, and industrial compounds among others that are thought to have long-term adverse effects on human health and ecosystems. This review is focused on reporting the ability of biologically based wastewater treatment systems to remove EOCs and the main elimination mechanisms and degradation processes (i.e., biodegradation, photodegradation, phytoremediation, and sorption) taking place in constructed wetlands, ponds, and Daphnia and fungal reactors.

  20. Efficient removal of chromate and arsenate from individual and mixed system by malachite nanoparticles.

    PubMed

    Saikia, Jiban; Saha, Bedabrata; Das, Gopal

    2011-02-15

    Malachite nanoparticles of 100-150 nm have been efficiently and for the first time used as an adsorbent for the removal of toxic arsenate and chromate. We report a high adsorption capacity for chromate and arsenate on malachite nanoparticle from both individual and mixed solution in pH ∼4-5. However, the adsorption efficiency decreases with the increase of solution pH. Batch studies revealed that initial pH, temperature, malachite nanoparticles dose and initial concentration of chromate and arsenate were important parameters for the adsorption process. Thermodynamic analysis showed that adsorption of chromate and arsenate on malachite nanoparticles is endothermic and spontaneous. The adsorption of these anions has also been investigated quantitatively with the help of adsorption kinetics, isotherm, and selectivity coefficient (K) analysis. The adsorption data for both chromate and arsenate were fitted well in Langmuir isotherm and preferentially followed the second order kinetics. The binding affinity of chromate is found to be slightly higher than arsenate in a competitive adsorption process which leads to the comparatively higher adsorption of chromate on malachite nanoparticles surface.

  1. Selective encapsulation of cesium ions using the cyclic peptide moiety of surfactin: Highly efficient removal based on an aqueous giant micellar system.

    PubMed

    Taira, Toshiaki; Yanagisawa, Satohiro; Nagano, Takuto; Zhu, Yanbei; Kuroiwa, Takayoshi; Koumura, Nagatoshi; Kitamoto, Dai; Imura, Tomohiro

    2015-10-01

    Cyclic peptide of surfactin (SF) is one of the promising environment-friendly biosurfactants abundantly produced by microorganisms such as Bacillus subtilis. SF is also known to act as an ionophore, wherein alkali metal ions can be trapped in the cyclic peptide. Especially, SF is expected to show high affinity for Cs(+) because of the distinctive cavity size and coordination number. In this study, we reported the specific interaction between SF and Cs(+) and succeeded in the highly efficient removal of Cs(+) from water using giant SF micelles as a natural sorbent. The specific interaction between SF and Cs(+) to form their inclusion complex was revealed by nuclear magnetic resonance (NMR) and Fourier transform infrared (FT-IR) spectroscopy. We found that SF micelles selectively encapsulate Cs(+), which was suggested by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). A highly effective separation of Cs(+) immobilized on the surface of the SF micelles was also achieved through facile centrifugal ultrafiltration in 91% even in coexisting with other alkali metal ions such as Na(+) and K(+). Thus, the use of the giant micellar system of SF with its high Cs(+) affinity and distinctive assembling properties would be a new approach for the treatment of contaminated soil and water.

  2. Process for removing carbonate from wells

    SciTech Connect

    Derowisch, R.W.

    1989-11-14

    This patent describes a method of removing carbonate deposited in a water supply well by inflowing groundwater. It comprises: treating a supply of water by means of a membrane system for desalinization which places the water in an aggressive state of chemical inequilibrium and ion imbalance having a keen affinity for carbonate; pumping a fluid comprising the treated supply of water, without restabilization, into the well to react with the deposited carbonate; and flushing the product of the reaction from the well.

  3. Oxygen Limited Bioreactors System For Nitrogen Removal Using Immobilized Mix Culture

    NASA Astrophysics Data System (ADS)

    Pathak, B. K.; Sumino, T.; Saiki, Y.; Kazama, F.

    2005-12-01

    Recently nutrients concentrations especially nitrogen in natural water is alarming in the world wide. Most of the effort is being done on the removal of high concentration of nitrogen especially from the wastewater treatment plants. The removal efficiency is targeted in all considering the effluent discharge standard set by the national environment agency. In many cases, it does not meet the required standard and receiving water is being polluted. Eutrophication in natural water bodies has been reported even if the nitrogen concentration is low and self purification of natural systems itself is not sufficient to remove the nitrogen due to complex phenomenon. In order to recover the pristine water environment, it is very essential to explore bioreactor systems for natural water systems using immobilized mix culture. Microorganism were entrapped in Polyethylene glycol (PEG) prepolymer gel and cut into 3mm cubic immobilized pellets. Four laboratory scale micro bio-reactors having 0.1 L volumes were packed with immobilized pellets with 50% compact ratio. RUN1, RUN2, RUN3 and RUN4 were packed with immobilized pellets from reservoirs sediments, activated sludge (AS), mixed of AS, AG and biodegradable plastic and anaerobic granules (AG) respectively. Water from Shiokawa Reservoirs was feed to all reactors with supplemental ammonia and nitrite nitrogen as specified in the results and discussions. The reactors were operated dark incubated room in continuous flow mode with hydraulic retention time of 12 hours under oxygen limiting condition. Ammonium, nitrate nitrite nitrogen and total organic carbon (TOC) concentrations were measured as described in APWA and AWWA (1998). Laboratory scale four bioreactors containing different combination of immobilized cell were monitored for 218 days. Influent NH4+-N and NO2--N concentration were 2.27±0.43 and 2.05±0.41 mg/l respectively. Average dissolved oxygen concentration and pH in the reactors were 0.40-2.5 mg/l and pH 6

  4. Reclaim System Design of Indium Tin Oxide Thin-Film Removal from Color Filters of Displays

    NASA Astrophysics Data System (ADS)

    Pa, Pai-Shan

    2008-09-01

    A newly design precision reclaim system using electrochemical machining as an etching process for indium tin oxide (ITO) thin-film removal from the color filter surface of a displays is presented. Through the ultra precise etching of the nanostructure, the semiconductor industry can effectively recycle defective products, thereby reducing production costs. A large gyration diameter of a cathode combined with a small gap width between the cathode and a workpiece takes less time for the same amount of ITO removed. An adequate feed rate of color filters combined with a sufficient electric power produces fast machining. Pulsed direct current and higher rotational speed of the cathode can improve the effects of dregs discharge and are advantageous to be combined with a high feed rate of workpieces. Electrochemical machining only requires a short time to easily and cleanly remove ITO films.

  5. Development of a Scalable Process Control System for Chemical Soil Washing to Remove Uranyl Oxide

    DTIC Science & Technology

    2015-05-01

    is reactive, oxidizing once it has been deposited into soil. The recovery process needs a variety of measurement systems for precisely locating the...medical imaging material, etc.), toxic or hazardous materials such as pesticides or asbestos , consumer products such as refrigerators or...2012), the soil fines remain contaminated by tightly bound DU oxides. The leaching system removes uranium from these soil fines and deposits the

  6. Frequency estimation for optical coherent M-QAM system without removing modulated data phase

    NASA Astrophysics Data System (ADS)

    Yu, Song; Cao, Yinwen; Leng, Haijun; Wu, Guohua; Gu, Wanyi

    2012-08-01

    For optical coherent M-ary quadrature amplitude modulation (M-QAM) system, the frequency offset can be extracted directly by applying Fast Fourier Transform (FFT) to the signal's argument, without removing the modulated data phase. By categorizing the constellation points and rotating some constellation points by π/4, this algorithm is robust to extract the frequency offset against the noise. Numerical simulations of 16-QAM and 256-QAM coherent systems are presented to demonstrate this algorithm.

  7. Sorbent Structural Testing on Carbon Dioxide Removal Sorbents for Advanced Exploration Systems

    NASA Technical Reports Server (NTRS)

    Watson, David; Knox, James C.; West, Phillip; Bush, Richard

    2016-01-01

    Long term space missions require carbon dioxide removal systems that can function with minimal downtime required for maintenance, low power consumption and maximum efficiency for CO2 removal. A major component of such a system are the sorbents used for the CO2 and desiccant beds. Sorbents must not only have adequate CO2 and H2O removal properties, but they must have the mechanical strength to prevent structural breakdown due to pressure and temperature changes during operation and regeneration, as well as resistance to breakdown due to moisture in the system from cabin air. As part of the studies used to select future CO2 sorbent materials, mechanical tests are performed on various zeolite sorbents to determine mechanical performance while dry and at various humidified states. Tests include single pellet crush, bulk crush and attrition tests. We have established a protocol for testing sorbents under dry and humid conditions, and previously tested the sorbents used on the International Space Station carbon dioxide removal assembly. This paper reports on the testing of a series of commercial sorbents considered as candidates for use on future exploration missions.

  8. Nitrogen removal in an upflow sludge blanket (USB) reactor combined by aerobic biofiltration systems.

    PubMed

    Jun, H B; Park, S M; Park, J K; Choi, C O; Lee, J S

    2004-01-01

    A new nitrogen removal process (up-flow sludge blanket and aerobic filter, USB-AF) was proposed and tested with real sewage. In the USB reactor, the larger part of influent organic and nitrogen matters were removed, and ammonia was effectively oxidized in the subsequent aerobic filter. The role of the aerobic filter was to convert ammonia into nitrate, an electron acceptor that could convert soluble organic matters into volatile suspended solid (VSS) in the USB. The accumulated as well as influent VSS in the USB was finally degraded to fermented products that were another good carbon source for denitrification. Total COD, settleable COD and soluble COD in the raw sewage were 325, 80 and 140 mg/l, respectively. Most unsettleable COD as well as some SCOD in the influent was successfully removed in the USB. TCOD removal in the anoxic filter was by denitrification with the recycled nitrate. Low COD input to the aerobic filter could increase nitrification efficiency, reduce the start-up period and save the aeration energy in the USB-AF system. About 95% of ammonia was nitrified in the aerobic filter with no relation to the influent ammonia concentration. Denitrification efficiency of the recycled nitrate in the anoxic filter was about 85, 83, and 72% at recycle ratios of 100, 200, and 300%, respectively. T-N removal efficiency was 70% at recycle ratio of 300%.

  9. Surface-modified biochar in a bioretention system for Escherichia coli removal from stormwater.

    PubMed

    Lau, Abbe Y T; Tsang, Daniel C W; Graham, Nigel J D; Ok, Yong Sik; Yang, Xin; Li, Xiang-Dong

    2017-02-01

    Bioretention systems have been recommended as one of the best management practices for low impact development for water recycling/reuse systems. Although improvement of the stormwater quality has been reported regarding pollutants eliminations such as suspended solids and heavy metals, a substantial removal of indicator bacteria is required for possible non-potable reuse. This study investigated the efficiency of wood biochar with H2SO4-, H3PO4-, KOH-, and amino-modifications for E. coli removal from synthetic stormwater under intermittent flow. The H2SO4-modified biochar showed a specific surface area of 234.7 m(2) g(-1) (approximately double the area of original biochar), whereas a substantial reduction in surface area was found with amino-modified biochar. The E. coli removal (initial concentration of 0.3-3.2 × 10(6) CFU mL(-1)) by modified biochars as filter media was very promising with, for example, over 98% removal efficiency in the first 20 pore volumes of stormwater infiltration and over 92% removal by the end of the second infiltration cycle. Only a small portion of E. coli attached on the modified biochars (<0.3%, except KOH- and amino-modified biochars) was remobilized during the drainage phase of intermittent flow. The high removal capacity and stability against drainage were attributed to the high surface area, porous structure, and surface characteristics (e.g. hydrophobicity and O-containing functional groups) of the biochars. Thus, the H2SO4-modified biochar appeared to give the best treatment performance.

  10. Removal of pamidronate from bone in rats using systemic and local chelation

    PubMed Central

    Howie, R. Nicole; Bhattacharyya, Maryka; Salama, Mohamed; El Refaey, Mona; Isales, Carlos; Borke, James; Daoudi, Asma; Medani, Fardous; Elsalanty, Mohammed

    2015-01-01

    Objectives Bisphosphonates become adsorbed on hydroxyapatite crystals in the bone matrix. In case of side-effects, stopping the treatment would not affect the bisphosphonates already deposited in bone. This study tests the feasibility of in-vivo targeted removal of bisphosphonates from bone using chelating agents. Design 32 Sprague Dawley rats were given an injection of fluorescent pamidronate (OsteoSense EX; 0.16 nmol/g). They were treated with either systemic (cadmium) or local [ethylenediaminetetraacetic (EDTA) or citric acid (CA)] chelating agents to induce the removal of the bisphosphonate from bone. We evaluated the decrease in fluorescence in the alveolar bone, femur, tibia, and vertebrae. We also analyzed the systemic effects of treatment. Results Systemic chelation reduced the pamidronate signal universally. However, the maximum reduction was observed in the alveolar bone and femur (22% and 21%, p values 0.008 and 0.028, respectively). Systemic chelation did not impair calcium homeostasis. The chelation effect was not due to a systemic toxic effect on the liver or kidney. On the other hand local chelation at the extraction site significantly (p=0.011) decreased the pamidronate signal at bony surfaces of the socket. Conclusions Systemic and local chelating agents can remove bisphosphonate from bone. This study establishes a new concept for the prevention of side effects of bisphosphonates during high-risk situations. PMID:26431826

  11. An Improved Design for Air Removal from Aerospace Fluid Loop Coolant Systems

    NASA Technical Reports Server (NTRS)

    Ritchie, Stephen M. C.; Holladay, Jon B.; Holt, J. Mike; Clark, Dallas W.

    2003-01-01

    Aerospace applications with requirements for large capacity heat removal (launch vehicles, platforms, payloads, etc.) typically utilize a liquid coolant fluid as a transport media to increase efficiency and flexibility in the vehicle design. An issue with these systems however, is susceptibility to the presence of noncondensable gas (NCG) or air. The presence of air in a coolant loop can have numerous negative consequences, including loss of centrifugal pump prime, interference with sensor readings, inhibition of heat transfer, and coolant blockage to remote systems. Hardware ground processing to remove this air is also cumbersome and time consuming which continuously drives recurring costs. Current systems for maintaining the system free of air are tailored and have demonstrated only moderate success. An obvious solution to these problems is the development and advancement of a passive gas removal device, or gas trap, that would be installed in the flight cooling system simplifying the initial coolant fill procedure and also maintaining the system during operations. The proposed device would utilize commercially available membranes thus increasing reliability and reducing cost while also addressing both current and anticipated applications. In addition, it maintains current pressure drop, water loss, and size restrictions while increasing tolerance for pressure increases due to gas build-up in the trap.

  12. Laboratory and field evaluation of a pretreatment system for removing organics from produced water.

    PubMed

    Kwon, Soondong; Sullivan, Enid J; Katz, Lynn E; Bowman, Robert S; Kinney, Kerry A

    2011-09-01

    Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. This "produced water" is characterized by saline water containing a variety of pollutants, including water soluble and immiscible organics and many inorganic species. To reuse produced water, removal of both the inorganic dissolved solids and organic compounds is necessary. In this research, the effectiveness of a pretreatment system consisting of surfactant modified zeolite (SMZ) adsorption followed by a membrane bioreactor (MBR) was evaluated for simultaneous removal of carboxylates and hazardous substances, such as benzene, toluene, ethylbenzene, and xylenes (BTEX) from saline-produced water. A laboratory-scale MBR, operated at a 9.6-hour hydraulic residence time, degraded 92% of the carboxylates present in synthetic produced water. When BTEX was introduced simultaneously to the MBR system with the carboxylates, the system achieved 80 to 95% removal of BTEX via biodegradation. These results suggest that simultaneous biodegradation of both BTEX and carboxylate constituents found in produced water is possible. A field test conducted at a produced water disposal facility in Farmington, New Mexico confirmed the laboratory-scale results for the MBR and demonstrated enhanced removal of BTEX using a treatment train consisting of SMZ columns followed by the MBR. While most of the BTEX constituents of the produced water adsorbed onto the SMZ adsorption system, approximately 95% of the BTEX that penetrated the SMZ and entered the MBR was biodegraded in the MBR. Removal rates of acetate (influent concentrations of 120 to 170 mg/L) ranged from 91 to 100%, and total organic carbon (influent concentrations as high as 580 mg/L) ranged from 74 to 92%, respectively. Organic removal in the MBR was accomplished at a low biomass concentration of 1 g/L throughout the field trial. While the transmembrane pressure during the laboratory-scale tests was well-controlled, it rose

  13. Impact of Cr(VI) on P removal performance in enhanced biological phosphorus removal (EBPR) system based on the anaerobic and aerobic metabolism.

    PubMed

    Fang, Jing; Sun, Pei-de; Xu, Shao-juan; Luo, Tao; Lou, Ju-qing; Han, Jing-yi; Song, Ying-qi

    2012-10-01

    Influence of Cr(VI) on P removal in enhanced biological phosphorus removal (EBPR) system was investigated with respect to the composition of poly-phosphate-accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs), the transformation of poly-β-hydroxyalkanoates (PHA) and glycogen, enzymes' activities, and the intracellular Cr. Whether EBPR system could revive after Cr(VI) shock was also explored. Results showed P removal performance was completely inhibited by Cr(VI) with the concentration more than 5 mg L(-1). PAOs were more sensitive to Cr(VI) than GAOs and the other bacteria were. PHA consumption, glycogen synthesis and adenylate kinase's activity had been inhibited by 5 mg L(-1) Cr(VI). Both adenylate kinase's activity and P removal efficiency were negatively correlated with the intracellular Cr. Recovery experiments revealed that P removal performance with 5 mg L(-1) Cr(VI) shock could revive after a 2-day recovery treatment, while systems with high level Cr(VI) (20 and 60 mg L(-1)) shock could not.

  14. Interaction between common antibiotics and a Shewanella strain isolated from an enhanced biological phosphorus removal activated sludge system.

    PubMed

    Liu, Hang; Yang, Yongkui; Ge, Yanhui; Zhao, Lin; Long, Sha; Zhang, Ruochun

    2016-12-01

    With increasing production and consumption, more antibiotics are discharged into wastewater treatment plants and generally cannot be sufficiently removed. Because of the complexities of biological treatment processes, the fates of antibiotics and their effects on microorganisms, particularly those involved in the phosphorus removal system, are still unclear. Here, a Shewanella strain was isolated from an enhanced biological phosphorus removal (EBPR) system and was found to have the ability to remove phosphorus (P) and chemical oxygen demand (CODcr). Antibiotics affected the Shewanella strain through metabolism of the three main intracellular polymers, altering the ability of the strain to remove P and CODcr. These effects varied with the structure and concentration of the antibiotics. The Shewanella strain removed cefalexin and amoxicillin by degradation or adsorption, producing 2-hydroxy-3-phenyl pyrazine from cefalexin. This study enabled the recognition of the effect and removal of antibiotics during wastewater treatment.

  15. Method and device for removing a non-aqueous phase liquid from a groundwater system

    DOEpatents

    Looney, Brian B.; Rossabi, Joseph; Riha, Brian D.

    2002-01-01

    A device for removing a non-aqueous phase liquid from a groundwater system includes a generally cylindrical push-rod defining an internal recess therein. The push-rod includes first and second end portions and an external liquid collection surface. A liquid collection member is detachably connected to the push-rod at one of the first and second end portions thereof. The method of the present invention for removing a non-aqueous phase liquid from a contaminated groundwater system includes providing a lance including an external hydrophobic liquid collection surface, an internal recess, and a collection chamber at the bottom end thereof. The lance is extended into the groundwater system such that the top end thereof remains above the ground surface. The liquid is then allowed to collect on the liquid collection surface, and flow downwardly by gravity into the collection chamber to be pumped upwardly through the internal recess in the lance.

  16. Comparison of four aquatic plant treatment systems for nutrient removal from eutrophied water.

    PubMed

    Li, Jihua; Yang, Xiaoying; Wang, Zhengfang; Shan, Ying; Zheng, Zheng

    2015-03-01

    Nutrient removal behaviors of four aquatic plant treatment systems (Oenanthe javanica, Iris pseudacorus L., Canna lily, and Potamogeton crispus) were systematically examined and compared. The kinetics of nutrient uptake were conducted with the standard depletion method. All four aquatic species exhibited a strong preference of ammonium nitrogen (NH4(+)-N) over nitrate nitrogen (NO3(-)-N) and nitrite nitrogen (NO2(-)-N). Main pathways of nutrient removal in the aquatic plant treatment system were examined in details. It was estimated that direct assimilation by plants accounted for 28.2-34.5% of N reduction and 25.2-33.4% of P reduction while substrate absorption accounted for 7.2-25.5% of N reduction and 7.3-25.0% of P reduction. The activity of urease and phosphatase in the substrates could indicate the aquatic plant treatment system's capability for reducing TN and soluble P load.

  17. Optimization of cryogenic and heat removal system of space borne magnets

    NASA Astrophysics Data System (ADS)

    Musicki, Z.; Hilal, M. A.; McIntosh, G. E.

    Space-based superconducting magnets require a refrigerator system to maintain operating temperature at the design value. The magnets use helium gas cooled shields and multilayer insulation. Refrigerator power is determined based on the heat leak to the shields and to the magnet winding, as well as current leads and charging losses. Electric power is supplied by a power source such as an SP-100-type reactor or solar panels. Cryogenic and heat removal system masses included in the optimization are: the insulation and shields, the refrigerator, the power supply and the heat removal panel. The system is optimized to determine the optimum radiator temperature, superinsulation thickness, helium mass flow rate and helium inlet temperature to the shields.

  18. Stabilization of affinity-tagged recombinant protein during/after its production in a cell-free system using wheat-germ extract.

    PubMed

    Kawarasaki, Yasuaki; Yamada, Yasuhiro; Ichimori, Maki; Shinbata, Tomoya; Kohda, Katsunori; Nakano, Hideo; Yamane, Tsuneo

    2003-01-01

    We found that the affinity tag fused to the carboxyl (C-) terminal of a single-chain Fv (scFv) antibody was proteolytically degraded in a wheat germ cell-free protein synthesis system. The addition of two extra residues of glycine to the tail of the cMyc tag significantly increased the stability of the tag, suggesting that wheat endogenous carboxypeptidase(s) play a primary role in the C-terminal tag-specific degradation. In addition to the modification of the tag sequence, addition of diisopropyl fluorophosphate, which is known as an inhibitor of carboxypeptidases, prevented the cMyc tag sequence degradation. The effects of other protease inhibitors on the translation reaction and stability of the synthesized protein are also reported.

  19. GD-aided IOL (input-output linearisation) controller for handling affine-form nonlinear system with loose condition on relative degree

    NASA Astrophysics Data System (ADS)

    Zhang, Yunong; Chen, Dechao; Jin, Long; Zhang, Yinyan; Yin, Yonghua

    2016-04-01

    Input-output linearisation (IOL) may encounter a singularity problem when applied to the tracking control of affine-form nonlinear system (AFNS), which may not have a well-defined relative degree. The singularity problem has occurred in the area of control for decades. In this paper, we incorporate the gradient dynamics (GD) into IOL, which leads to the GD-aided IOL method to solve the singularity problem, with the proposition of the loose condition on relative degree. Moreover, detailed theoretical analyses on tracking-error bound and convergence performance of the corresponding GD-aided IOL controller are presented. Simulations and comparisons substantiate that the proposed GD-aided IOL method is capable of completing the tracking-control task and conquering the singularity encountered in the AFNS.

  20. Final Report on NASA Portable Laser Coating Removal Systems Field Demonstrations and Testing

    NASA Technical Reports Server (NTRS)

    Rothgeb, Matthew J; McLaughlin, Russell L.

    2008-01-01

    Processes currently used throughout the National Aeronautics and Space Administration (NASA) to remove corrosion and coatings from structures, ground service equipment, small parts and flight components result in waste streams consisting of toxic chemicals, spent media blast materials, and waste water. When chemicals are used in these processes they are typically high in volatile organic compounds (VOC) and are considered hazardous air pollutants (HAP). When blast media is used, the volume of hazardous waste generated is increased significantly. Many of the coatings historically used within NASA contain toxic metals such as hexavalent chromium, and lead. These materials are highly regulated and restrictions on worker exposure continue to increase. Most recently the Occupational Safety and Health Administration (OSHA) reduced the permissible exposure limit (PEL) for hexavalent chromium (CrVI) from 52 to 5 micrograms per cubic meter of air as an 8-hour time-weighted average. Hexavalent chromium is found in numerous pretreatment and primer coatings used within the Space Shuttle Program. In response to the need to continue to protect assets within the agency and the growing concern over these new regulations, NASA is researching different ways to continue the required maintenance of both facility and flight equipment in a safe, efficient, and environmentally preferable manner. The use of laser energy to prepare surfaces for a variety of processes, such as corrosion and coating removal, weld preparation, and non destructive evaluation (NDE) is a relatively new application of the technology that has been proven to be environmentally preferable and in many cases less labor intensive than currently used removal methods. The novel process eliminates VOCs and blast media and captures the removed coatings with an integrated vacuum system. This means that the only waste generated are the coatings that are removed, resulting in an overall cleaner process. The development of a

  1. Intensified nitrogen and phosphorus removal in a novel electrolysis-integrated tidal flow constructed wetland system.

    PubMed

    Ju, Xinxin; Wu, Shubiao; Zhang, Yansheng; Dong, Renjie

    2014-08-01

    A novel electrolysis-integrated tidal flow constructed wetland (CW) system was developed in this study. The dynamics of intensified nitrogen and phosphorus removal and that of hydrogen sulphide control were evaluated. Ammonium removal of up to 80% was achieved with an inflow concentration of 60 mg/L in wetland systems with and without electrolysis integration. Effluent nitrate concentration decreased from 2 mg/L to less than 0.5 mg/L with the decrease in current intensity from 1.5 mA/cm(2) to 0.57 mA/cm(2) in the electrolysis-integrated wetland system, thus indicating that the current intensity of electrolysis plays an important role in nitrogen transformations. Phosphorus removal was significantly enhanced, exceeding 95% in the electrolysis-integrated CW system because of the in-situ formation of a ferric iron coagulant through the electro-dissolution of a sacrificial iron anode. Moreover, the electrolyzed wetland system effectively inhibits sulphide accumulation as a result of a sulphide precipitation coupled with ferrous-iron electro-dissolution and/or an inhibition of bacterial sulphate reduction under increased aerobic conditions.

  2. Ammonium Removal by the Oxygen-Limited Autotrophic Nitrification-Denitrification System

    PubMed Central

    Kuai, Linping; Verstraete, Willy

    1998-01-01

    The present lab-scale research reveals the potential of implementation of an oxygen-limited autotrophic nitrification-denitrification (OLAND) system with normal nitrifying sludge as the biocatalyst for the removal of nitrogen from nitrogen-rich wastewater in one step. In a sequential batch reactor, synthetic wastewater containing 1 g of NH4+-N liter−1 and minerals was treated. Oxygen supply to the reactor was double-controlled with a pH controller and a timer. At a volumetric loading rate (Bv) of 0.13 g of NH4+-N liter−1 day−1, about 22% of the fed NH4+-N was converted to NO2−-N or NO3−-N, 38% remained as NH4+-N, and the other 40% was removed mainly as N2. The specific removal rate of nitrogen was on the order of 50 mg of N liter−1 day−1, corresponding to 16 mg of N g of volatile suspended solids−1 day−1. The microorganisms which catalyzed the OLAND process are assumed to be normal nitrifiers dominated by ammonium oxidizers. The loss of nitrogen in the OLAND system is presumed to occur via the oxidation of NH4+ to N2 with NO2− as the electron acceptor. Hydroxylamine stimulated the removal of NH4+ and NO2−. Hydroxylamine oxidoreductase (HAO) or an HAO-related enzyme might be responsible for the loss of nitrogen. PMID:9797314

  3. Assessing the feasibility of two hybrid MBR systems using PAC for removing macro and micropollutants.

    PubMed

    Alvarino, T; Torregrosa, N; Omil, F; Lema, J M; Suarez, S

    2016-03-24

    The removal of 10 organic micropollutants (OMPs) was studied in two MBRs using different types of membrane (flat sheet microfiltration, MF, and hollow fiber ultrafiltration, UF) operated under aerobic conditions with direct dosing of powdered activated carbon (PAC) in the mixed liquor. In both reactors high COD degradation and nitrification were achieved (>95%), while nitrate removal was only observed after PAC addition. The adsorbent improved the operation of both systems (sludge properties and microbial diversity) which resulted in an enhancement of the quality of the final effluent. The operation with both types of membrane was feasible being the UF system slightly better in terms of the quality of the final effluent. The strategy of 250 mg/L of PAC additions every 35 days was validated according to the results obtained for the removal of the most recalcitrant OMPs, such as diclofenac and carbamazepine. Concerning the type of membrane, only significant differences were observed for diclofenac and roxithromycin, which were better removed in the UF configuration. These differences were attributed to sorption and/or further biotransformation processes occurring in the cake layer.

  4. Efficient taste and odour removal by water treatment plants around the Han River water supply system.

    PubMed

    Ahn, H; Chae, S; Kim, S; Wang, C; Summers, R S

    2007-01-01

    Seven major water treatment plants in Seoul Metropolitan Area, which are under Korea Water Resources Corporation (KOWACO)'s management, take water from the Paldang Reservoir in the Han River System for drinking water supply. There are taste and odour (T&O) problems in the finished water because the conventional treatment processes do not efficiently remove the T&O compounds. This study evaluated T&O removal by ozonation, granular activated carbon (GAC) treatment, powder activated carbon (PAC) and an advanced oxidation process in a pilot-scale treatment plant and bench-scale laboratory experiments. During T&O episodes, PAC alone was not adequate, but as a pretreatment together with GAC it could be a useful option. The optimal range of ozone dose was 1 to 2 mg/L at a contact time of 10 min. However, with ozone alone it was difficult to meet the T&O target of 3 TON and 15 ng/L of MIB or geosmin. The GAC adsorption capacity for DOC in the three GAC systems (F/A, GAC and O3 + GAC) at an EBCT of 14 min is mostly exhausted after 9 months. However, substantial TON removal continued for more than 2 years (>90,000 bed volumes). GAC was found to be effective for T&O control and the main removal mechanisms were adsorption capacity and biodegradation.

  5. Removal of manganese from water using combined chelation/membrane separation systems.

    PubMed

    Han, S C; Choo, K H; Choi, S J; Benjamin, M M

    2005-01-01

    The addition of the chelating polymer polyacrylic acid (PAA) to assist in the removal of manganese from groundwater by membranes was investigated using membranes with different pore sizes under various operating conditions. Negligible manganese removal was achieved with the UF and NF membranes at acidic pH values, but removals exceeding 90% could be achieved at elevated pH (pH 9), presumably due to the formation of manganese hydroxides. Mn removal increased substantially when PAA was added to the feed solution, due to chelation of Mn by the PAA and rejection of the chelates by the membranes. The chelate could be broken at acidic pH, releasing free PAA that could then be separated from the Mn ions and reused. Smaller PAA molecules were lost in the first regeneration cycle, but negligible PAA was lost in subsequent cycles. In the systems with PAA, nitrate ions were rejected more efficiently than in the PAA-free systems, presumably because of electrical repulsion between nitrate ions and PAA sorbed on the membrane surface. With increasing PAA dose, the volumetric flux first decreased and then increased; the latter result was accompanied by a change in the physical-chemical form of the polymers, as indicated by an increase in turbidity.

  6. Removal of nitrogen by a layered soil infiltration system during intermittent storm events.

    PubMed

    Cho, Kang Woo; Song, Kyung Guen; Cho, Jin Woo; Kim, Tae Gyun; Ahn, Kyu Hong

    2009-07-01

    The fates of various nitrogen species were investigated in a layered biological infiltration system under an intermittently wetting regime. The layered system consisted of a mulch layer, coarse soil layer (CSL), and fine soil layer (FSL). The effects of soil texture were assessed focusing on the infiltration rate and the removal of inorganic nitrogen species. The infiltration rate drastically decreased when the uniformity coefficient was larger than four. The ammonium in the synthetic runoff was shown to be removed via adsorption during the stormwater dosing and nitrification during subsequent dry days. Stable ammonium adsorption was observed when the silt and clay content of CSL was greater than 3%. This study revealed that the nitrate leaching was caused by nitrification during dry days. Various patterns of nitrate flushing were observed depending on the soil configuration. The washout of nitrate was more severe as the silt/clay content of the CSL was greater. However, proper layering of soil proved to enhance the nitrate removal. Consequently, a strictly sandy CSL over FSL with a silt and clay content of 10% was the best configuration for the removal of ammonium and nitrate.

  7. BOA: Asbestos pipe-insulation removal robot system. Phase I. Topical report, November 1993--December 1994

    SciTech Connect

    Schempf, H.; Bares, J.E.

    1995-01-01

    Based on several key design criteria and site visits, we developed a Robot design and built a system which automatically strips the lagging and insulation from the pipes, and encapsulates them under complete vacuum operation. The system can operate on straight runs of piping in horizontal or vertical orientations. Currently we are limited to four-inch diameter piping without obstacles as well as a somewhat laborious emplacement and removal procedure. Experimental results indicated that the current robotic abatement process is sound yet needs to be further expanded and modified. One of the main discoveries was that a longitudinal cut to fully allow the paddles to dig in and compress the insulation off the pipe is essential. Furthermore, a different cutting method might be explored to alleviate the need for a deeper cut and to enable a combination of certain functions such as compression and cutting. Unfortunately due to a damaged mechanism caused by extensive testing, we were unable to perform vertical piping abatement experiments, but foresee no trouble in implementing them in the next proposed Phase. Other encouraging results have BOA removing asbestos at a rate of 4-5 ft./h compared to 3 ft./h for manual removal of asbestos with a 3-person crew. However, we feel confident that we can double the asbestos removal rate by improving cutting speed, and increasing the length of the BOA robot. The containment and vacuum system on BOA is able to achieve the regulatory requirement for airborne fiber emissions of 0.01 fibers/ccm/8-hr. shift. Currently, BOA weighs about 117 pounds which is more than a human is permitted to lift overhead under OSHA requirements (i.e., 25 pounds). We are considering designing the robot into two components (i.e., locomotor section and cutter/removal section) to aid human installation as well as incorporating composite materials. A more detailed list of all the technical modifications is given in this topical report.

  8. Theoretical proton affinity and fluoride affinity of nerve agent VX.

    PubMed

    Bera, Narayan C; Maeda, Satoshi; Morokuma, Keiji; Viggiano, Al A

    2010-12-23

    Proton affinity and fluoride affinity of nerve agent VX at all of its possible sites were calculated at the RI-MP2/cc-pVTZ//B3LYP/6-31G* and RI-MP2/aug-cc-pVTZ//B3LYP/6-31+G* levels, respectively. The protonation leads to various unique structures, with H(+) attached to oxygen, nitrogen, and sulfur atoms; among which the nitrogen site possesses the highest proton affinity of -ΔE ∼ 251 kcal/mol, suggesting that this is likely to be the major product. In addition some H(2), CH(4) dissociation as well as destruction channels have been found, among which the CH(4) + [Et-O-P(═O)(Me)-S-(CH(2))(2)-N(+)(iPr)═CHMe] product and the destruction product forming Et-O-P(═O)(Me)-SMe + CH(2)═N(+)(iPr)(2) are only 9 kcal/mol less stable than the most stable N-protonated product. For fluoridization, the S-P destruction channel to give Et-O-P(═O)(Me)(F) + [S-(CH(2))(2)-N-(iPr)(2)](-) is energetically the most favorable, with a fluoride affinity of -ΔE ∼ 44 kcal. Various F(-) ion-molecule complexes are also found, with the one having F(-) interacting with two hydrogen atoms in different alkyl groups to be only 9 kcal/mol higher than the above destruction product. These results suggest VX behaves quite differently from surrogate systems.

  9. Nitrogen removal and nitrifying and denitrifying bacteria quantification in a stormwater bioretention system.

    PubMed

    Chen, Xiaolu; Peltier, Edward; Sturm, Belinda S M; Young, C Bryan

    2013-03-15

    In this study, we examine the biological processes involved in ammonia and nitrate removal in a bioretention system characterized by low infiltration rates and long drainage times. The system removed 33% of influent nitrate and 56% of influent total nitrogen. While influent ammonia concentrations were low (<0.3 mg/L), the bioretention cell also removed ammonia produced within the treatment system. Soil cores collected from the bioretention cell were analyzed for total 16S rDNA and both nitrification and denitrification genes (amoA, nirS, nirK, norB, and nosZ) using quantitative PCR. Total bacterial 16S rDNA levels in the surface layer were similar to those in very sandy soils. Gene counts for both nitrification and denitrification genes decreased as a function of depth in the media, and corresponded to similar changes in total 16S rDNA. The abundance of denitrification genes was also positively correlated with the average inundation time at each sampling location, as determined by modeling of stormwater data from a three-year period. These results suggest that both nitrification and denitrification can occur in bioretention media. Time of saturation, filter medium, and organic carbon content can all affect the extent of denitrification in bioretention systems.

  10. GEOMETRY, HEAT REMOVAL AND KINETICS SCOPING MODELS FOR HYDROGEN STORAGE SYSTEMS

    SciTech Connect

    Hardy, B

    2007-11-16

    It is recognized that detailed models of proposed hydrogen storage systems are essential to gain insight into the complex processes occurring during the charging and discharging processes. Such insight is an invaluable asset for both assessing the viability of a particular system and/or for improving its design. The detailed models, however, require time to develop and run. Clearly, it is much more efficient to begin a modeling effort with a good system design and to progress from that point. To facilitate this approach, it is useful to have simplified models that can quickly estimate optimal loading and discharge kinetics, effective hydrogen capacities, system dimensions and heat removal requirements. Parameters obtained from these models can then be input to the detailed models to obtain an accurate assessment of system performance that includes more complete integration of the physical processes. This report describes three scoping models that assess preliminary system design prior to invoking a more detailed finite element analysis. The three models address the kinetics, the scaling and heat removal parameters of the system, respectively. The kinetics model is used to evaluate the effect of temperature and hydrogen pressure on the loading and discharge kinetics. As part of the kinetics calculations, the model also determines the mass of stored hydrogen per mass of hydride (in a particular reference form). As such, the model can determine the optimal loading and discharge rates for a particular hydride and the maximum achievable loading (over an infinite period of time). The kinetics model developed with the Mathcad{reg_sign} solver, runs in a mater of seconds and can quickly be used to identify the optimal temperature and pressure for either the loading or discharge processes. The geometry scoping model is used to calculate the size of the system, the optimal placement of heat transfer elements, and the gravimetric and volumetric capacities for a particular

  11. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, REMOVAL OF ARSENIC IN DRINKING WATER: DELTA INDUSTRIAL SERVICES, INC., CAMPWATER PORTA-5 SYSTEM

    EPA Science Inventory

    The CampWater system uses ozonation followed by cartridge filtration to remove arsenic via co-precipitation. The system utilizes ozone to oxidize iron and arsenic (III) to arsenic (V). The arsenic bound to the iron precipitates is then removed by cartridge filtration. No additi...

  12. Final Report on Portable Laser Coating Removal Systems Field Demonstrations and Testing

    NASA Technical Reports Server (NTRS)

    Rothgeb, Matthew J.; McLaughlin, Russell L.

    2008-01-01

    Processes currently used throughout the National Aeronautics and Space Administration (NASA) to remove corrosion and coatings from structures, ground service equipment and small components results in waste streams consisting of toxic chemicals, spent media blast materials, and waste water. When chemicals are used in these processes they are typically high in volatile organic compounds (VOC) and are considered hazardous air pollutants (HAP). When blast media is used, the volume of hazardous waste generated is increased significantly. Many of the coatings historically used within NASA contain toxic metals such as hexavalent chromium, and lead. These materials are highly regulated and restrictions on worker exposure continue to increase. Most recently the EPA reduced the permissible exposure limit (PEL) for hexavalent chromium. The new standard lowers OSHA's PEL for hexavalent chromium from 52 to 5 micrograms of Cr(V1) per cubic meter of air as an 8-hour time-weighted average. Hexavalent chromium is found in the pretreatment and primer coatings used within the Shuttle Program. In response to the need to continue to protect assets within the agency and the growing concern over these new regulations, NASA is researching different ways to continue the required maintenance of both facility and flight equipment in a safe, efficient and environmentally preferable manner. The use of laser energy to remove prepare surfaces for a variety of processes, such as corrosion and coating removal, weld preparation and non destructive evaluation is a relatively new technology that has shown itself to be environmentally preferable and in many cases less labor intensive than currently used removal methods. The development of a Portable Laser Coating Removal System (PLCRS) started as the goal of a Joint Group on Pollution Prevention (JG-PP) project, led by the Air Force, where several types of lasers in several configurations were thoroughly evaluated. Following this project, NASA decided

  13. Cooling system for removing metabolic heat from an hermetically sealed spacesuit

    NASA Technical Reports Server (NTRS)

    Webbon, B. W.; Vykukal, H. C.; Williams, B. A. (Inventor)

    1978-01-01

    An improved cooling and ventilating system is described for removing metabolic heat, waste gases and water vapor generated by a wearer of an hermetically sealed spacesuit. The cooling system was characterized by a body suit, having a first circuit for simultaneously establishing a cooling flow of water through the thorax and head sections of the body suit. Circulation patches were included mounted in the thorax section and head section of the body suit. A second circuit for discharing a flow of gas throughout the spacesuit and a disconnect unit for coupling the circuits with a life support system externally related to the spacesuit were provided.

  14. Application of vascular aquatic plants for pollution removal, energy and food production in a biological system

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Barlow, R. M.; Mcdonald, R. C.

    1975-01-01

    Vascular aquatic plants such as water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb., when utilized in a controlled biological system (including a regular program of harvesting to achieve maximum growth and pollution removal efficiency), may represent a remarkably efficient and inexpensive filtration and disposal system for toxic materials and sewage released into waters near urban and industrial areas. The harvested and processed plant materials are sources of energy, fertilizer, animal feed, and human food. Such a system has industrial, municipal, and agricultural applications.

  15. MBBR system performance improvement for petroleum hydrocarbon removal using modified media with activated carbon.

    PubMed

    Sayyahzadeh, Amir Hossein; Ganjidoust, Hossein; Ayati, Bita

    2016-01-01

    Moving bed biofilm reactor (MBBR) system has a successful operation in the treatment of different types of wastewater. Since the media, i.e. the place of growth and formation of biofilm, play the main role in the treatment in this system, MBBR systems were operated in the present research with modified Bee-cell media. Activated carbon granules of almond or walnut shells were placed in media pores to improve the treatment of refinery oil wastewater and their operation with MBBR system was compared with the conventional Bee-cell media. In these experiments, the effects of organic loading rate, hydraulic retention time (HRT), media filling ratio (MFR), and activated carbon concentration (ACC) used in the media were investigated on the operation of MBBR systems. The analysis of results estimated the optimal values of HRT, MFR, and ACC used in the media between the studied levels, being equal to 22 h, 50%, and 7.5 g/L, respectively. Under these conditions, total petroleum hydrocarbons removal efficiencies for MBBR systems using Bee-cell media with carbon of almond, carbon of walnut shells, and a carbon-free system were 95 ± 1.17%, 91 ± 1.11%, and 57 ± 1.7%, respectively, which confirms the adsorption ability of systems with the media containing activated carbon in the removal of petroleum compounds from wastewater.

  16. Simulation and applications of a novel modified SBR system for biological nutrient removal.

    PubMed

    Wu, W; Timpany, P; Dawson, B

    2001-01-01

    Dynamic simulation and applications of a novel, continuous-fed, constant level modified sequencing batch reactor for biological nutrient removal are presented. The underlying mathematical model and practical applications of the simulation are discussed. Case studies are presented to illustrate the applications as well as the flexibility of the system in meeting different wastewater treatment requirements. Operation experience from full-scale wastewater treatment plant demonstrates the reliability, ease of operation and high efficiency of the system. Average BOD5, total nitrogen, total phosphorus and TSS removals of 97, 81, 88 and 94% are achieved respectively on an annual basis with little operator attention. Consistently high waste activated sludge concentrations are demonstrated, averaging approximately 20,000 mg/L.

  17. Anode shroud for off-gas capture and removal from electrolytic oxide reduction system

    DOEpatents

    Bailey, James L.; Barnes, Laurel A.; Wiedmeyer, Stanley G.; Williamson, Mark A.; Willit, James L.

    2014-07-08

    An electrolytic oxide reduction system according to a non-limiting embodiment of the present invention may include a plurality of anode assemblies and an anode shroud for each of the anode assemblies. The anode shroud may be used to dilute, cool, and/or remove off-gas from the electrolytic oxide reduction system. The anode shroud may include a body portion having a tapered upper section that includes an apex. The body portion may have an inner wall that defines an off-gas collection cavity. A chimney structure may extend from the apex of the upper section and be connected to the off-gas collection cavity of the body portion. The chimney structure may include an inner tube within an outer tube. Accordingly, a sweep gas/cooling gas may be supplied down the annular space between the inner and outer tubes, while the off-gas may be removed through an exit path defined by the inner tube.

  18. Occurrence and removal of microbial indicators from municipal wastewaters by nine different MBR systems.

    PubMed

    Hirani, Zakir M; Decarolis, James F; Lehman, Geno; Adham, Samer S; Jacangelo, Joseph G

    2012-01-01

    Nine different membrane bioreactor (MBR) systems with different process configurations (submerged and external), membrane geometries (hollow-fiber, flat-sheet, and tubular), membrane materials (polyethersulfone (PES), polyvinylidene fluoride (PVDF), and polytetrafluoroethylene (PTFE)) and membrane nominal pore sizes (0.03-0.2 μm) were evaluated to assess the impact of influent microbial concentration, membrane pore size and membrane material and geometries on removal of microbial indicators by MBR technology. The log removal values (LRVs) for microbial indicators increased as the influent concentrations increased. Among the wide range of MBR systems evaluated, the total and fecal coliform bacteria and indigenous MS-2 coliphage were detected in 32, 9 and 15% of the samples, respectively; the 50th percentile LRVs were measured at 6.6, 5.9 and 4.5 logs, respectively. The nominal pore sizes of the membranes, membrane materials and geometries did not show a strong correlation with the LRVs.

  19. Disease activity in systemic lupus erythematosus is associated with an altered expression of low-affinity Fcγ receptors and costimulatory molecules on dendritic cells

    PubMed Central

    Carreño, Leandro J; Pacheco, Rodrigo; Gutierrez, Miguel A; Jacobelli, Sergio; Kalergis, Alexis M

    2009-01-01

    Dendritic cells (DCs) play a pivotal role in the interface between immunity and maintenance of peripheral tolerance. The capture of immunoglobulin G (IgG)-containing immune complexes (ICs) by low-affinity Fcγ receptors (FcγRs) expressed on DCs may influence the immunogenicity/tolerogenicity of these cells, depending on the activating/inhibitory potential of FcγRs. Because of the key role that low-affinity FcγRs play in determining the magnitude of the response in IC-driven inflammation, these receptors are likely to play a role in autoimmune diseases, such as systemic lupus erythematosus (SLE). To evaluate if an altered expression of costimulatory molecules and/or FcγRs could account for disease severity, we evaluated the expression of these molecules on immature and mature DCs derived from peripheral blood monocytes of SLE patients and healthy donors. Our results show an increased expression of the costimulatory molecules CD40 and CD86. Furthermore, the ratio of CD86/CD80 is higher in SLE patients compared with healthy donors. Conversely, while the expression of activating FcγRs was higher on DCs from SLE patients, expression of inhibitory FcγRs was lower, compared with DCs obtained from healthy donors. As a result, the activating to inhibitory FcγR ratio was significantly higher in DCs from SLE patients. The altered ratio of activating/inhibitory FcγRs on mature DCs showed a significant correlation with the activity of SLE, as determined by the SLE Disease Activity Index (SLEDAI) score. We postulate that the increased ratio of activating/inhibitory FcγRs expressed on DCs from SLE patients can contribute to the failure of peripheral tolerance in the IC-mediated phase of autoimmune pathogenesis. PMID:20067533

  20. Nitrogen removal from the surface runoff of a field scale greenhouse vegetable production system.

    PubMed

    Min, Ju; Lu, Kouping; Zhao, Xu; Sun, Haijun; Zhang, Hailin; Shi, Weiming

    2015-01-01

    Nutrient losses from greenhouse vegetable production systems may impair water quality in the Taihu Lake Region of China. We studied the characteristics of nitrogen (N) lost via runoff from greenhouse vegetable systems and strategies for minimizing N entering water bodies. A two-year experiment at a field scale was conducted to monitor N surface runoff. An eco-ditch (148 m(2)) and a low N input paddy field (135 kg N ha⁻¹, 550 m²) were designed to remove N from the surface runoff of a 25 × 50 m greenhouse vegetable field. The greenhouse was not covered from late June to mid-October each year, and runoff occurred multiple times during this period. Annual total N loss in runoff from the greenhouse vegetable site was 25.3 and 33.5 kg ha⁻¹ in 2010 and 2011, respectively. Nitrate-N was the major form of N lost in the runoff. The average runoff volume was 289 mm (varied from 221 to 357 mm), which contained 15.7 (varied from 3.3 to 39.2 mg L⁻¹) mg L⁻¹ total N. The eco-ditch system and the wetland paddy field (WPF) effectively reduced total N discharge; the removal rates reached 49.9% and 58.7% and the average removal capacities were 12.4 g N m⁻² and 4.1 g N m⁻² in 2010 and 2011, respectively. The combined system of the ecological ditch-WPF removed almost 79% total N in the runoff. Ecological ditch or paddy wetland can be a water management option available to growers in this region to economically reduce pollutants in agricultural runoff.

  1. A Residual Chlorine Removal Method to Allow Drinking Water Monitoring by Biological Early Warning Systems

    DTIC Science & Technology

    2005-03-18

    Aquatic Biomonitor Diagram Page 6 Figure 3. Dechlorinator System Page 9 Figure 4. Sodium Bisulfite Response Data Page 12 Table 1. Size of Fish Used in... sodium bisulfite into chlorinated water containing 1.5 to 2.0 mg/L TRC was effective in removing TRC-related toxicity during a nine month evaluation of...Fredericksburg, VA. Because of 2.3 Dechlorinator Testing the low toxicity of sodium bisulfite and This section describes the procedures the high concentrations

  2. Tritium Removal System for Airtight Room in High-flux Advanced Neutron Application Reactor (HANARO) - 12110

    SciTech Connect

    Yim, Sung Paal; Lee, Jung Hee; Kim, Hyung-Kyoo; Jung, Hoan Sung; Lee, Cheo Kyung; Yoo, Sun Kyun

    2012-07-01

    An Airtight room was installed to prevent the diffusion of tritium from the instrument room to other areas in HANARO. It was isolated by a robust structure and the inside was closed tightly. A Tritium removal system located outside the instrument room was connected to the airtight room to lower the tritium concentration when the workers enter the room for maintenance of the instruments. The tritium concentration and the dew point in the airtight room were continuously measured during the operation of the tritium removal system. The data were analyzed by using a model. There was a difference between the measured tritium concentration and the one obtained by the model. It is believed that the difference is due to the change of the generation rate of tritium which would increase as the dew point becomes lower. Based on this assumption, the previous equation was revised to better express the performance of the tritium removal system. It was re-estimated that the change of tritium concentration in an airtight room could be predicted well by using a model and equation proposed in the previous study. It was confirmed that there was a definite difference between the measured tritium concentration and the one obtained by equation from the model. It is believed that the difference is due to the change of the generation rate of tritium which would increase as the dew point becomes lower. Based on this assumption, the generation rate of tritium was controlled to have higher value and the change of tritium concentration in airtight room could be more correctly predicted. By using the revised equation, the tritium removal system would be operated more effectively. (authors)

  3. Affine Sphere Relativity

    NASA Astrophysics Data System (ADS)

    Minguzzi, E.

    2017-03-01

    We investigate spacetimes whose light cones could be anisotropic. We prove the equivalence of the structures: (a) Lorentz-Finsler manifold for which the mean Cartan torsion vanishes, (b) Lorentz-Finsler manifold for which the indicatrix (observer space) at each point is a convex hyperbolic affine sphere centered on the zero section, and (c) pair given by a spacetime volume and a sharp convex cone distribution. The equivalence suggests to describe (affine sphere) spacetimes with this structure, so that no algebraic-metrical concept enters the definition. As a result, this work shows how the metric features of spacetime emerge from elementary concepts such as measure and order. Non-relativistic spacetimes are obtained replacing proper spheres with improper spheres, so the distinction does not call for group theoretical elements. In physical terms, in affine sphere spacetimes the light cone distribution and the spacetime measure determine the motion of massive and massless particles (hence the dispersion relation). Furthermore, it is shown that, more generally, for Lorentz-Finsler theories non-differentiable at the cone, the lightlike geodesics and the transport of the particle momentum over them are well defined, though the curve parametrization could be undefined. Causality theory is also well behaved. Several results for affine sphere spacetimes are presented. Some results in Finsler geometry, for instance in the characterization of Randers spaces, are also included.

  4. Low temperature biological phosphorus removal and partial nitrification in a pilot sequencing batch reactor system.

    PubMed

    Yuan, Qiuyan; Oleszkiewicz, Jan A

    2011-01-01

    Partial nitrification and biological phosphorus removal appear to hold promise of a cost-effective and sustainable biological nutrient removal process. Pilot sequencing batch reactors (SBRs) were operated under anaerobic/aerobic configuration for 8 months. It was found that biological phosphorus removal can be achieved in an SBR system, along with the partial nitrification process. Sufficient volatile fatty acids supply was the key for enhanced biological phosphorus removal. This experiment demonstrated that partial nitrification can be achieved even at low temperature with high dissolved oxygen (>3 mg/L) concentration. Shorter solid retention time (SRT) for nitrite oxidizing bacteria (NOB) than for ammonia oxidizing bacteria due to the nitrite substrate limitation at the beginning of the aeration cycle was the reason that caused NOB wash-out. Controlling SRT should be the strategy for an SBR operated in cold climate to achieve partial nitrification. It was also found that the aerobic phosphorus accumulating organisms' P-uptake was more sensitive to nitrite inhibition than the process of anaerobic P-release.

  5. Impact of butyrate on microbial selection in enhanced biological phosphorus removal systems.

    PubMed

    Begum, Shamim A; Batista, Jacimaria R

    2014-01-01

    Microbial selection in an enhanced biological phosphorus removal system was investigated in a laboratory-scale sequencing batch reactor fed exclusively with butyrate as a carbon source. As reported in the few previous studies, butyrate uptake was slow and phosphorus (P) release occurred during the entire anaerobic period. Polyphosphate-accumulating organism (PAO), i.e. Candidatus Accumulibacter phosphatis (named as Accumulibacter), glycogen-accumulating organisms (GAOs), i.e. Candidatus Competibacter phosphatis (named as Competibacter) and Defluviicoccus-related, tetrad-forming alphaproteobacteria (named as Defluviicoccus) were identified using fluorescence in situ hybridization analysis. The results show that Accumulibacter and Defluviicoccus were selected in the butyrate-fed reactor, whereas Competibacter was not selected. P removal was efficient at the beginning of the experiment with an increasing percentage relative abundance (% RA) of PAOs. The % RA of Accumulibacter and Defluviicoccus increased from 13% to 50% and 8% to 16%, respectively, and the % RA of Competibacter decreased from 8% to 2% during the experiment. After 6 weeks, P removal deteriorated with the poor correlation between the percentage of P removal and % RA of GAOs.

  6. Impacts of carbon source addition on denitrification and phosphorus uptake in enhanced biological phosphorus removal systems.

    PubMed

    Begum, Shamim A; Batista, Jacimaria R

    2013-01-01

    In this study, simultaneous denitrification and phosphorus (P) removal were investigated in batch tests using nitrified mixed liquor and secondary wastewater influent from a full-scale treatment plant and different levels of acetate and propionate as supplemental carbon sources. Without supplemental carbon source, denitrification occurred at low rate and P release and P uptake was negatively affected (i.e., P removal of only 59.7%). When acetate and propionate were supplied, denitrification and P release occurred simultaneously under anoxic conditions. For acetate and propionate at a C/N stoichiometric ratio of 7.6, P release was negatively affected by denitrification. For acetate, the percent P removal and denitrification were very similar for C/N ratios of 22 (5X stoichiometric) and 59 (10X stoichiometric). For propionate, both percent P removal and denitrification deteriorated for C/N ratios of 22 (5X stoichiometric) and 45 (10X stoichiometric). It was observed that carbon source added in excess to stoichiometric ratio was consumed in the aerobic zone, but P was not taken up. This implies that PAO bacteria may utilize the excess carbon source in the aerobic zone rather than their polyhydroxyalkanoate (PHA) reserves, thereby promoting deterioration of the system.

  7. Assessment of full-scale biological nutrient removal systems upgraded with physico-chemical processes for the removal of emerging pollutants present in wastewaters from Mexico.

    PubMed

    Estrada-Arriaga, Edson Baltazar; Cortés-Muñoz, Juana Enriqueta; González-Herrera, Arturo; Calderón-Mólgora, César Guillermo; de Lourdes Rivera-Huerta, Ma; Ramírez-Camperos, Esperanza; Montellano-Palacios, Leticia; Gelover-Santiago, Silvia Lucila; Pérez-Castrejón, Sara; Cardoso-Vigueros, Lina; Martín-Domínguez, Alejandra; García-Sánchez, Liliana

    2016-11-15

    Two full-scale biological nutrient removal systems upgraded with three physico-chemical processes (coagulation, chemical precipitation, and neutral Fenton) were evaluated in order to determine the removal of emerging pollutants (EPs) present in municipal wastewater from Mexico. Between 41 and 55 EPs were detected in the influents of two wastewater treatment plants (WWTPs), including personal care products (PPCPs), antibiotics, analgesics, antiepileptics, antilipidemics, antihypertensives, antiseptics, stimulants, and hormones. Emerging pollutants were detected at concentrations ranging from 0.69ng/L to 94,600ng/L. High concentrations of emerging pollutants were found during dry season. WWTP 1, integrated by oxidation ditches and UV light lamps, showed removal efficiencies of EPs between 20% and 22%. On the other hand, WWTP 2 consisted of anaerobic/anoxic/aerobic tanks coupled with two disinfection processes; chlorine dioxide and UV light lamps, for which the removal of EPs was significant (up to 80%). The concentrations of emerging pollutants in WWTP 1 effluent was found within a rangeremovals, compared to those of WWTP 1, due to a greater activity of the simultaneous nitrification-denitrification processes, hydraulic retention time, and solids retention time. The compounds that were more persistent with removals below 50% in both effluents were: carbamazepine, dehydronifedipine, meprobamate, sertraline, propranolol, propoxyphene, norverapamil, diazepam, alprazolam, sulfamethoxazole, metoprolol, ofloxacin, norfloxacin, fluoxetine, erythromycin-H2O, diphenhydramine, dehydronifedipine, clarithromycin, hydrochlorothiazide, and albuterol. The application of neutral Fenton reaction as post-treatment for the two effluents from the WWTPs is promising for the removal of emerging pollutants (up to 100

  8. Nitrogen removal in a combined system: vertical vegetated bed over horizontal flow sand bed.

    PubMed

    Kantawanichkul, S; Neamkam, P; Shutes, R B

    2001-01-01

    Pig farm wastewater creates various problems in many areas throughout Thailand. Constructed wetland systems are an appropriate, low cost treatment option for tropical countries such as Thailand. In this study, a combined system (a vertical flow bed planted with Cyperus flabelliformis over a horizontal flow sand bed without plants) was used to treat settled pig farm wastewater. This system is suitable for using in farms where land is limited. The average COD and nitrogen loading rate of the vegetated vertical flow bed were 105 g/m2 x d and 11 g/m2 x d respectively. The wastewater was fed intermittently at intervals of 4 hours with a hydraulic loading rate of 3.7 cm/d. The recirculation of the effluent increased total nitrogen (TN) removal efficiency from 71% to 85%. The chemical oxygen demand (COD) and total Kjeldahl nitrogen (TKN) removal efficiencies were 95% and 98%. Nitrification was significant in vertical flow Cyperus bed, and the concentration of nitrate increased by a factor of 140. The horizontal flow sand bed enhanced COD removal and nitrate reduction was 60%. Plant uptake of nitrogen was 1.1 g N/m2 x d or dry biomass production was 2.8 kg/m2 over 100 days.

  9. System Analysis for Decay Heat Removal in Lead-Bismuth Cooled Natural Circulated Reactors

    SciTech Connect

    Takaaki Sakai; Yasuhiro Enuma; Takashi Iwasaki; Kazuhiro Ohyama

    2002-07-01

    Decay heat removal analyses for lead-bismuth cooled natural circulation reactors are described in this paper. A combined multi-dimensional plant dynamics code (MSG-COPD) has been developed to conduct the system analysis for the natural circulation reactors. For the preliminary study, transient analysis has been performed for a 100 MWe lead-bismuth-cooled reactor designed by Argonne National Laboratory (ANL). In addition, decay heat removal characteristics of a 400 MWe lead-bismuth-cooled natural circulation reactor designed by Japan Nuclear Cycle Development Institute (JNC) has been evaluated by using MSG-COPD. PRACS (Primary Reactor Auxiliary Cooling System) is prepared for the JNC's concept to get sufficient heat removal capacity. During 2000 sec after the transient, the outlet temperature shows increasing tendency up to the maximum temperature of 430 Centigrade, because the buoyancy force in a primary circulation path is temporary reduced. However, the natural circulation is recovered by the PRACS system and the out let temperature decreases successfully. (authors)

  10. System Analysis for Decay Heat Removal in Lead-Bismuth-Cooled Natural-Circulation Reactors

    SciTech Connect

    Sakai, Takaaki; Enuma, Yasuhiro; Iwasaki, Takashi

    2004-03-15

    Decay heat removal analyses for lead-bismuth-cooled natural-circulation reactors are described in this paper. A combined multidimensional plant dynamics code (MSG-COPD) has been developed to conduct the system analysis for the natural-circulation reactors. For the preliminary study, transient analysis has been performed for a 300-MW(thermal) lead-bismuth-cooled reactor designed by Argonne National Laboratory. In addition, decay heat removal characteristics of a 400-MW(electric) lead-bismuth-cooled natural-circulation reactor designed by the Japan Nuclear Cycle Development Institute (JNC) has been evaluated by using MSG-COPD. The primary reactor auxiliary cooling system (PRACS) is prepared for the JNC concept to get sufficient heat removal capacity. During 2000 s after the transient, the outlet temperature shows increasing tendency up to the maximum temperature of 430 deg. C because the buoyancy force in a primary circulation path is temporarily reduced. However, the natural circulation is recovered by the PRACS system, and the outlet temperature decreases successfully.

  11. Integration and optimization of the gas removal system for hybrid-cycle OTEC power plants

    SciTech Connect

    Rabas, T.J.; Panchal, C.B.; Stevens, H.C. )

    1990-02-01

    A preliminary design of the noncondensible gas removal system for a 10 mWe, land-based hybrid-cycle OTEC power plant has been developed and is presented herein. This gas removal system is very different from that used for conventional power plants because of the substantially larger and continuous noncondensible gas flow rates and lower condenser pressure levels which predicate the need for higher-efficiency components. Previous OTEC studies discussed the need for multiple high-efficiency compressors with intercoolers; however, no previous design effort was devoted to the details of the intercoolers, integration and optimization of the intercoolers with the compressors, and the practical design constraints and feasibility issues of these components. The resulting gas removal system design uses centrifugal (radial) compressors with matrix-type crossflow aluminum heat exchangers as intercoolers. Once-through boiling of ammonia is used as the heat sink for the cooling and condensing of the steam-gas mixture. A computerized calculation method was developed for the performance analysis and subsystem optimization. For a specific number of compressor units and the stream arrangement, the method is used to calculate the dimensions, speeds, power requirements, and costs of all the components.

  12. Microbial selection on enhanced biological phosphorus removal systems fed exclusively with glucose.

    PubMed

    Begum, Shamim A; Batista, Jacimaria R

    2012-05-01

    The microbial selection on an enhanced biological phosphorus removal (EBPR) system was investigated in a laboratory-scale sequencing batch reactor fed exclusively with glucose as the carbon source. Fluorescence In Situ Hybridization analysis was performed to target two polyphosphate accumulating organisms (PAOs) (i.e., Candidatus Accumulibacter phosphatis and Microlunatus phosphovorus) and two glycogen accumulating organisms (GAOs) (i.e., Candidatus Competibacter phosphatis and Micropruina glycogenica). The results show that glucose might not select for Candidatus Accumulibacter phosphatis. However, Microlunatus phosphovorus, Candidatus Competibacter phosphatis, and Micropruina glycogenica might be selected. The highest percent relative abundance (% RA) of Candidatus Accumulibacter phosphatis was about 42%; this occurred at the beginning of the experimental period when phosphorus removal was efficient. However, the % RA of these bacteria decreased, reaching below 4% at the end of the run. The maximum % RA of Microlunatus phosphovorus, Candidatus Competibacter phosphatis, and Micropruina glycogenica was about 21, 37, 17%, respectively. It appears that a higher glucose concentration might be detrimental for Microlunatus phosphovorus and Micropruina glycogenica. Results also indicate a dominance of GAOs over PAOs when EBPR systems are fed with glucose. It is possible that the GAOs outcompete the PAOs at low pH values; it has been reported that at low pH, GAOs use glycogen as the energy source to uptake glucose. As a result, P-removal deteriorated. Therefore, glucose is not a strong candidate as a carbon source to supplement EBPR systems that do not contain sufficient volatile fatty acids.

  13. Cetylpyridinium chloride/magnetic alginate beads: an efficient system to remove p-nitrophenol from wastewater

    NASA Astrophysics Data System (ADS)

    Obeid, Layaly; Bee, Agnes; Talbot, Delphine; Abramson, Sebastien; Welschbillig, Mathias

    2014-05-01

    The adsorption process is one of the most efficient methods to remove pollutants from wastewater provided that suitable adsorbents are used. In order to produce environmentally safe adsorbents, natural polymers have received increasing attention in recent years. Thus, alginate, a polysaccharide extracted from brown seaweeds, is extensively used as inexpensive, non-toxic and efficient biosorbent. Furthermore, it has been shown that the encapsulation of magnetic materials in alginate beads facilitates their recovery from wastewater after the adsorption step, by the use of an external magnetic field gradient, obtained with a magnet or an electromagnet [1, 2]. In the present work, we have studied the adsorption affinity of magnetic alginate beads (called magsorbents)for p-nitrophenol (PNP), used as a hydrophobic pollutant, in presence of cetylpyridinium chloride (CPC), a cationic surfactant. First, the effect of different parameters (pH solution, contact time, surfactant initial concentration…) on the adsorption of CPC on the alginate beads was investigated. Adsorption of the surfactant occurs due to electrostatic attractions between its cationic head groups and negative carboxylate functions of the alginate beads. At larger surfactant concentrations, adsorption is also due to the interaction between the hydrocarbon chains of CPC forming aggregated structures capable of solubilizing hydrophobic solutes. In a second step, we showed that PNP can reach up to 95% of adsorption in the beads in presence of CPC, although the pollutant is poorly adsorbed by alginate in absence of the surfactant. At highest CPC concentrations, desorption occurs as micellar solubilization is preferred over coadsorption. Our magsorbents appear to efficiently remove both cationic surfactant and hydrophobic pollutants and we hope that this fundamental research will be helpful for the future development of magnetically assisted processes in water treatment plants. 1. A.Bee, D.Talbot, S.Abramson, V

  14. Comorbid depression/anxiety and teeth removed: Behavioral Risk Factor Surveillance System 2010

    PubMed Central

    Wiener, RC; Wiener, MA; McNeil, DW

    2015-01-01

    Objective The purpose of this study was to examine the association between participants 1) who reported having had clinical diagnoses of depression and anxiety with 6+ teeth removed and 2) who reported having had clinical diagnoses of depression and anxiety with edentulism. Methods The Behavioral Risk Factor Surveillance System (BRFSS) Survey 2010 was used for the study. Analyses involved using SAS 9.3 to determine variable frequencies, Rao–Scott chi-square bivariate analyses, and Proc Surveylogistic for the logistic regressions on complex survey designs. Participants eligibility included being 18 years or older and having complete data on depression, anxiety, and number of teeth removed. Results There were 76 292 eligible participants; 13.4% reported an anxiety diagnosis, 16.7% reported a depression diagnosis, and 8.6% reported comorbid depression and anxiety. The adjusted logistic regression models were significant for anxiety and depression alone and in combination for 6+ teeth removed (AOR: anxiety 1.23; 95% CI: 1.10, 1.38; P = 0.0773; AOR: depression 1.23; 95% CI: 1.10, 1.37; P = 0.0275; P < 0.0001; and AOR: comorbid depression and anxiety 1.30; 95% CI: 1.14, 1.49; P = 0.0001). However, the adjusted models with edentulism as the outcome failed to reach significance. Conclusions Comorbid depression and anxiety are associated independently with 6+ teeth removed compared with 0–5 teeth removed in a national study conducted in United States. Comorbid depression and anxiety were not shown to be associated with edentulism as compared with any teeth present. PMID:25970143

  15. High-efficiency SO{sub 2} removal in utility FGD systems

    SciTech Connect

    Phillips, J.L.; Gray, S.; Dekraker, D.

    1995-11-01

    The U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI) have contracted with Radian Corporation to conduct full-scale testing, process modeling, and economic evaluations of six existing utility flue gas desulfurization (FGD) systems. The project objective is to evaluate low capital cost upgrades for achieving up to 98% sulfur dioxide (SO{sub 2}) removal efficiency in a variety of FGD system types. The systems include dual-loop, packed absorbers at Tampa Electric Company`s Big Bend Station; cocurrent, packed absorbers at Hoosier Energy`s Merom Station; dual-loop absorbers with perforated-plate trays at Southwestern Electric Power Company`s Pirkey Station; horizontal spray absorbers at PSI Energy`s Gibson Station; venturi scrubbers at Duquesne Light`s Elrama Station; and open stray absorbers at New york State Electric and Gas Corporations`s (NYSEG`s) Kintigh Station. All operate in an inhibited-oxidation mode except the system at Big Bend (forced oxidation), and all use limestone reagent except the Elrama system (Mg-lime). The program was conducted to demonstrate that upgrades such as performance additives and/or mechanical modifications can increase system SO{sub 2} removal at low cost. The cost effectiveness of each upgrade has been evaluated on the basis of test results and/or process model predictions for upgraded performance and utility-specific operating and maintenance costs. Results from this upgraded performance and utility-specific operating and maintenance costs. Results from this program may lead some utilities to use SO{sub 2} removal upgrades as an approach for compliance with phase 2 of Title IV of the Clean Air Act Amendments (CAAA) of 1990. This paper summarizes the results of testing, modeling, and economic evaluations that have been completed since July, 1994.

  16. Arsenic removal via ZVI in a hybrid spouted vessel/fixed bed filter system

    PubMed Central

    Calo, Joseph M.; Madhavan, Lakshmi; Kirchner, Johannes; Bain, Euan J.

    2012-01-01

    The description and operation of a novel, hybrid spouted vessel/fixed bed filter system for the removal of arsenic from water are presented. The system utilizes zero-valent iron (ZVI) particles circulating in a spouted vessel that continuously generates active colloidal iron corrosion products via the “self-polishing” action between ZVI source particles rolling in the moving bed that forms on the conical bottom of the spouted vessel. This action also serves as a “surface renewal” mechanism for the particles that provides for maximum utilization of the ZVI material. (Results of batch experiments conducted to examine this mechanism are also presented.) The colloidal material produced in this fashion is continuously captured and concentrated in a fixed bed filter located within the spouted vessel reservoir wherein arsenic complexation occurs. It is demonstrated that this system is very effective for arsenic removal in the microgram per liter arsenic concentration (i.e., drinking water treatment) range, reducing 100 μg/L of arsenic to below detectable levels (≪10 μg/L) in less than an hour. A mechanistic analysis of arsenic behavior in the system is presented, identifying the principal components of the population of active colloidal material for arsenic removal that explains the experimental observations and working principles of the system. It is concluded that the apparent kinetic behavior of arsenic in systems where colloidal (i.e., micro/nano) iron corrosion products are dominant can be complex and may not be explained by simple first or zeroth order kinetics. PMID:22539917

  17. Enhanced removal of organic matter and ammoniacal-nitrogen in a column experiment of tidal flow constructed wetland system.

    PubMed

    Sun, Guangzhi; Zhao, Yaqian; Allen, Stephen

    2005-01-26

    A tidal flow constructed wetland system was investigated for the removal of organic matter and ammoniacal-nitrogen from diluted piggery wastewater. The results demonstrated that the operation of tidal flow enhanced the transfer of oxygen into wetland matrices. The supply of oxygen by the operation (473 gO2/m2d) matched the demand for wastewater treatment. The overall oxygen consumption rate in the system was considerably higher than the typical rate obtainable in conventional wetlands; most oxygen being used for the decomposition of organic matter. Compared with conventional systems, the tidal flow system demonstrated greater efficiency in the removal of organic matter. Significant nitrification did not take place, although 27-48% ammonia was removed from the wastewater. Immobilization by microbial cells and adsorption were the likely routes to remove ammonia under the specific experiment conditions. Percentage removals of BOD5, NH4-N and SS increased after effluent recirculation at a ratio of 1:1 was employed.

  18. A portable system for acquiring and removing motion artefact from ECG signals

    NASA Astrophysics Data System (ADS)

    Griffiths, A.; Das, A.; Fernandes, B.; Gaydecki, P.

    2007-07-01

    A novel electrocardiograph (ECG) signal acquisition and display system is under development. It is designed for patients ranging from the elderly to athletes. The signals are obtained from electrodes integrated into a vest, amplified, digitally processed and transmitted via Bluetooth to a PC with a Labview ® interface. Digital signal processing is performed to remove movement artefact and electromyographic (EMG) noise, which severely distorts signal morphology and complicates clinical diagnosis. Independent component analysis (ICA) is also used to improve the signal quality. The complete system will integrate the electronics into a single module which will be embedded in the vest.

  19. SULFUR REMOVAL FROM PIPE LINE NATURAL GAS FUEL: APPLICATION TO FUEL CELL POWER GENERATION SYSTEMS

    SciTech Connect

    King, David L.; Birnbaum, Jerome C.; Singh, Prabhakar

    2003-11-21

    Pipeline natural gas is being considered as the fuel of choice for utilization in fuel cell-based distributed generation systems because of its abundant supply and the existing supply infrastructure (1). For effective utilization in fuel cells, pipeline gas requires efficient removal of sulfur impurities (naturally occurring sulfur compounds or sulfur bearing odorants) to prevent the electrical performance degradation of the fuel cell system. Sulfur odorants such as thiols and sulfides are added to pipeline natural gas and to LPG to ensure safe handling during transportation and utilization. The odorants allow the detection of minute gas line leaks, thereby minimizing the potential for explosions or fires.

  20. Application of the selective equipment removal system to D&D tasks

    SciTech Connect

    Noakes, M.W.; Hamel, W.R.; Dixon, W.E.

    1995-02-01

    The Selective Equipment Removal System has been designed as a generic and reconfigurable remote manipulation platform to demonstrate and evaluate mobile telerobotic concepts suitable for performing selective decontamination and dismantlement functions. Both radioactive and hazardous chemical environments dictate that human presence should be minimized in many of these activities. In addition, robotic deployment of large and heavy tools should improve safety of operation by limiting human proximity to tooling. Monotonous, repetitive, and high precision activities should also benefit by robotic completion. This paper discusses the development of the Selective Equipment Retrieval System and its remote manipulation platform, the Dual Arm Work Module, applicable tooling, and application to various decontamination and dismantlement tasks.

  1. Experimental evaluation of a breadboard heat and product-water removal system for a space-power fuel cell designed with static water removal and evaporative cooling

    NASA Technical Reports Server (NTRS)

    Hagedorn, N. H.; Prokipius, P. R.

    1977-01-01

    A test program was conducted to evaluate the design of a heat and product-water removal system to be used with fuel cell having static water removal and evaporative cooling. The program, which was conducted on a breadboard version of the system, provided a general assessment of the design in terms of operational integrity and transient stability. This assessment showed that, on the whole, the concept appears to be inherently sound but that in refining this design, several facets will require additional study. These involve interactions between pressure regulators in the pumping loop that occur when they are not correctly matched and the question of whether an ejector is necessary in the system.

  2. System A amino acid transporter SNAT2 shows subtype-specific affinity for betaine and hyperosmotic inducibility in placental trophoblasts.

    PubMed

    Nishimura, Tomohiro; Yagi, Risa; Usuda, Mariko; Oda, Kenji; Yamazaki, Mai; Suda, Sayaka; Takahashi, Yu; Okazaki, Fumiyasu; Sai, Yoshimichi; Higuchi, Kei; Maruyama, Tetsuo; Tomi, Masatoshi; Nakashima, Emi

    2014-05-01

    Betaine uptake is induced by hypertonic stress in a placental trophoblast cell line, and involvement of amino acid transport system A was proposed. Here, we aimed to identify the subtype(s) of system A that mediates hypertonicity-induced betaine uptake. Measurement of [(14)C]betaine uptake by HEK293 cells transiently transfected with human or rat sodium-coupled neutral amino acid transporters (SNATs), SNAT1, SNAT2 and SNAT4 revealed that only human and rat SNAT2 have betaine uptake activity. The Michaelis constants (Km) of betaine uptake by human and rat SNAT2 were estimated to be 5.3 mM and 4.6 mM, respectively. Betaine exclusively inhibited the uptake activity of SNAT2 among the rat system A subtypes. We found that rat SNAT1, SNAT2 and SNAT4 were expressed at the mRNA level under isotonic conditions, while expression of SNAT2 and SNAT4 was induced by hypertonicity in TR-TBT 18d-1 cells. Western blot analyses revealed that SNAT2 expression on plasma membrane of TR-TBT 18d-1 cells was more potently induced by hypertonicity than that in total cell lysate. Immunocytochemistry confirmed the induction of SNAT2 expression in TR-TBT 18d-1 cells exposed to hypertonic conditions and indicated that SNAT2 was localized on the plasma membrane in these cells. Our results indicate that SNAT2 transports betaine, and that tonicity-sensitive SNAT2 expression may be involved in regulation of betaine concentration in placental trophoblasts.

  3. Passive removal of silicone oil through 23 gauge transconjunctival sutureless vitrectomy system

    PubMed Central

    Siyal, Nisar Ahmed; Hargun, Lakhani Das; Wahab, Shahid

    2016-01-01

    Objective: To study the outcomes of passive removal of silicone oil by 23 Gauge Transconjunctival Sutureless Vitrectomy System. Methods: This prospective, consecutive case series study was conducted at Ophthalmology Department Unit I, Dow University of Health Sciences, Civil Hospital Karachi from January 2011 to December 2014. Only psuedophakic eyes with silicone oil temponade were selected. Main outcome measures were intra ocular pressure, time taken for removal of silicone oil, per operative and post operative complications. Pre and post operative IOP was compared by using two-tailed paired t-test and mean values with standard deviation were computed using difference of 95% confidence interval. Chi square test was applied for correlation of different variables. P-value of less than 0.05 was considered statistically significant. Results: Out of 79 patients who underwent passive ROSO, 38 (48.1%) were males. Mean age of patients was 47.5±7.1 (sd) years. Mean time taken for passive ROSO was 7.31±2.41 (sd) minutes. Pre and post operative intra ocular pressure shows statistically significant (p=0.000) decrease in IOP. Retinal redetachment found in 13 (16.5%) cases during follow up period. Conclusion: Passive removal of silicone oil with 23 G suture less vitrectomy system is safe and effective in terms of less per operative and post operative complications. In this simple technique, there is less tissue trauma and little time consumed so it provides more comfort to patients and surgeons as well. PMID:27375708

  4. Effectiveness of different oxidizing agents for removing sodium dodecylbenzenesulphonate in aqueous systems.

    PubMed

    Méndez-Díaz, J D; Sánchez-Polo, M; Rivera-Utrilla, J; Bautista-Toledo, M I

    2009-04-01

    The present study investigates the efficacy of various oxidizing treatments (ClO(-), ClO(2), KMnO(4), O(3), O(3)/H(2)O(2), O(3)/activated carbon) to remove from waters sodium dodecylbenzenesulphonate (SDBS), considered as model surfactant. Results obtained show that the use of ClO(-) and ClO(2) does not cause appreciable SDBS degradation. Additionally, in the case of ClO(-), trihalomethanes are generated, increasing system toxicity. Because the reaction kinetics between SDBS and KMnO(4) is very slow, a decrease in contaminant concentration is not observed, even at very acid pH values. SDBS reactivity with ozone is very low, with a kinetic constant (k(O)(3)) of 3.68 M(-1)s(-1), but its reactivity with HO() radicals is very high (k(OH)=1.16 x 10(10)M(-1)s(-1)), therefore O(3)/H(2)O(2) and O(3)/activated carbon, which can also generate HO(), appear as promising advanced oxidation processes to remove this contaminant from waters. The method based on ozone and activated carbon was the only process studied that produced both an increase in SDBS removal rate (due to the generation of HO() radicals in the O(3)-PAC or O(3)-GAC interaction) and a considerable reduction in the concentration of dissolved organic carbon in the system due to the PAC adsorbent properties.

  5. Submerged membrane adsorption hybrid system using four adsorbents to remove nitrate from water.

    PubMed

    Kalaruban, Mahatheva; Loganathan, Paripurnanda; Kandasamy, Jaya; Vigneswaran, Saravanamuthu

    2017-04-05

    Nitrate contamination of ground and surface waters causes environmental pollution and human health problems in many parts of the world. This study tests the nitrate removal efficiencies of two ion exchange resins (Dowex 21K XLT and iron-modified Dowex 21K XLT (Dowex-Fe)) and two chemically modified bio-adsorbents (amine-grafted corn cob (AG corn cob) and amine-grafted coconut copra (AG coconut copra)) using a dynamic adsorption treatment system. A submerged membrane (microfiltration) adsorption hybrid system (SMAHS) was used for the continuous removal of nitrate with a minimal amount of adsorbents. The efficiency of membrane filtration flux and replacement rate of adsorbent were studied to determine suitable operating conditions to maintain the effluent nitrate concentration below the WHO drinking standard limit of 11.3 mg N/L. The volume of water treated and the amount of nitrate adsorbed per gramme of adsorbent for all four flux tested were in the order Dowex-Fe > Dowex > AG coconut copra > AG corn cob. The volumes of water treated (L/g adsorbent) were 0.91 and 1.85, and the amount of nitrate removed (mg N/g adsorbent) were 9.8 and 22.2 for AG corn cob and Dowex-Fe, respectively, at a flux of 15 L/(m(2)/h).

  6. A comparison of the accuracy of two removable die systems with intact working casts.

    PubMed

    Aramouni, P; Millstein, P

    1993-01-01

    This study evaluated the reproducibility of die position using two removable die systems and two die stones. Poly(vinyl siloxane) impressions were made of a stainless steel, U-shaped arch with four evenly spaced abutments. Six groups were evaluated: Zeiser system/Fuji Rock; Zeiser system/Die Keen; solid cast/Fuji Rock; solid cast/Die Keen; Fuji Rock/Pindex; and Die Keen/Pindex. An optical comparator was used to measure the height of each abutment, the distance between the anterior abutments, and the distance between the posterior abutments. The Zeiser system with either Fuji Rock or Die Keen yielded the greatest accuracy. Die Keen exhibited more linear expansion than Fuji Rock, and solid casts had less distortion than the Pindex system.

  7. Dynamics analysis and GNC design of flexible systems for space debris active removal

    NASA Astrophysics Data System (ADS)

    Benvenuto, Riccardo; Salvi, Samuele; Lavagna, Michèle

    2015-05-01

    Active debris removal is one of current hot spots in space research, necessary for space exploitation durability. Different techniques have been proposed for this challenging task, among them the use of throw-nets and tow-tethers seems promising: that opens new challenges for Guidance Navigation and Control (GNC) design, especially whenever flexible connections are involved. Via numerical simulations using a multi-body dynamics simulation tool developed at Politecnico di Milano - Department of Aerospace Science and Technology, this paper shows that tethered-net systems are a promising technology to capture and remove space debris and discusses the main difficulties that are likely to take place during capture and disposal phases, particularly from a GNC point of view.

  8. How can liver toxins be removed? Filtration and adsorption with the Prometheus system.

    PubMed

    Vienken, Joerg; Christmann, Horst

    2006-04-01

    The application of extracorporeal blood circuits in liver failure therapy has its roots in the two functions of the liver, first as a detoxifying and second as a synthetizing organ. In contrast to hydrophilic uremic toxins, most liver toxins are hydrophobic and bind preferentially to blood proteins. Consequently, the majority of these compounds cannot be removed by hemodialysis or similar dialytic procedures. Current systems use albumin as a transport vehicle for hydrophobic compounds across high flux membranes (e.g. albumin-dialysis, molecular adsorbent recirculating system (MARS)). In contrast to these devices, the Prometheus system (Fresenius Medical Care, Bad Homburg, Germany) applies filtration across highly permeable membranes with a molecular weight cut-off of >300.000. These membranes facilitate a direct filtration of most of the toxin-bearing proteins. In a secondary circuit these toxins are then removed by adsorber beads assembled in specially designed cartridges. The protein-containing toxin-free solution returns to the primary circuit. Clinical testing of the Prometheus system's safety and efficacy parameters showed that cell counts and coagulation factors were not significantly affected. Total bilirubin-, bile acid- and plasma ammonia-levels were reduced in vivo by -21%, -43% and -40%, respectively. First successful therapeutic results have been obtained for patients treated for drug abuse and for patients waiting for transplantation. Thus, a combination of plasma fractionation with highly permeable membranes followed by a secondary circuit with adsorber cartridges proves to be the most effective method of removing toxic waste in liver failure. Further investigations will follow in order to extend the application of the Prometheus system to larger cohorts of patients.

  9. Integrated photo-bioelectrochemical system for contaminants removal and bioenergy production.

    PubMed

    Xiao, Li; Young, Erica B; Berges, John A; He, Zhen

    2012-10-16

    An integrated photobioelectrochemical (IPB) system was developed by installing a microbial fuel cell (MFC) inside an algal bioreactor. This system achieves the simultaneous removal from a synthetic solution of organics (in the MFC) and nutrients (in the algal bioreactor), and the production of bioenergy in electricity and algal biomass through bioelectrochemical and microbiological processes. During the one-year operation, the IPB system removed more than 92% of chemical oxygen demand, 98% of ammonium nitrogen, and 82% of phosphate and produced a maximum power density of 2.2 W/m(3) and 128 mg/L of algal biomass. The algal growth provided dissolved oxygen to the cathode reaction of the MFC, whereas electrochemical oxygen reduction on the MFC cathode buffered the pH of the algal growth medium (which was also the catholyte). The system performance was affected by illumination and dissolved oxygen. Initial energy analysis showed that the IPB system could theoretically produce enough energy to cover its consumption; however, further improvement of electricity production is desired. An analysis of the attached and suspended microbes in the cathode revealed diverse bacterial taxa typical of aquatic and soil bacterial communities with functional roles in contaminant degradation and nutrient cycling.

  10. Studies with an immobilized metal affinity chromatography cassette system involving binuclear triazacyclononane-derived ligands: automation of batch adsorption measurements with tagged recombinant proteins.

    PubMed

    Petzold, Martin; Coghlan, Campbell J; Hearn, Milton T W

    2014-07-18

    This study describes the determination of the adsorption isotherms and binding kinetics of tagged recombinant proteins using a recently developed IMAC cassette system and employing automated robotic liquid handling procedures for IMAC resin screening. These results confirm that these new IMAC resins, generated from a variety of different metal-charged binuclear 1,4,7-triaza-cyclononane (tacn) ligands, interact with recombinant proteins containing a novel N-terminal metal binding tag, NT1A, with static binding capacities similar to those obtained with conventional hexa-His tagged proteins, but with significantly increased association constants. In addition, higher kinetic binding rates were observed with these new IMAC systems, an attribute that can be positively exploited to increase process productivity. The results from this investigation demonstrate that enhancements in binding capacities and affinities were achieved with these new IMAC resins and chosen NT1A tagged protein. Further, differences in the binding performances of the bis(tacn) xylenyl-bridged ligands were consistent with the distance between the metal binding centres of the two tacn moieties, the flexibility of the ligand and the potential contribution from the aromatic ring of the xylenyl group to undergo π/π stacking interactions with the tagged proteins.

  11. Portable life support system regenerative carbon dioxide and water vapor removal by metal oxide absorbents preprototype hardware development and testing

    NASA Technical Reports Server (NTRS)

    Hart, Joan M.; Borghese, Joseph B.; Chang, Craig H.; Cusick, Robert J.

    1992-01-01

    NASA-Johnson has acquired a preprototype/full-scale metal oxide CO2 and humidity remover (MOCHR), together with its regeneration module. Tests conducted prior to delivery by the MOCHR's manufacturer have demonstrated the concurrent removal of H2O and CO2 at rates, and under conditions, that are applicable to EVA Portable Life Support Systems.

  12. Comparison of hydraulics and particle removal efficiencies in a mixed cell raceway and burrows pond rearing system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We compared the hydrodynamics of replicate experimental mixed cell and replicate standard Burrows pond rearing systems at the Dworshak National Fish Hatchery, ID, in an effort to identify methods for improved solids removal. We measured and compared the hydraulic residence time, particle removal eff...

  13. Small Community and Household Water Systems Research on Removal of Metals and Pesticides from Drinking Water Sources

    EPA Science Inventory

    The presentation entitled “Small Community and Household Water Systems Research on Removal of Metals and Pesticides from Drinking Water Sources” provides treatment alternatives for removal of metals and pesticides from surface and ground waters before human consumption. The pres...

  14. A three-stage system to remove mercury and dioxins in flue gases.

    PubMed

    Hylander, Lars D; Sollenberg, Hans; Westas, Håkan

    2003-03-20

    Mercury (Hg) from combustion of fossil fuels and waste is the dominant source of anthropogenic Hg emissions, globally amounting to more than 1500 t Hgyear(-1). These emissions must decrease substantially in order to counteract increasing environmental levels of Hg and reduce future toxic effects. Uppsala Energi AB, nowadays (May, 2002) Vattenfall Värme Uppsala AB, an energy company in Uppsala, Sweden, has invested in equipments for air and water pollution control of their three waste fired steam boilers. The flue gases are cleaned in three stages in series to meet the strict Swedish regulation. Electrostatic precipitators remove most dust in the first stage, wet scrubbers remove most water-soluble gases, and in the last stage a Filsorption unit removes most remaining impurities in particulate as well as gaseous form. The Filsorption process includes additives injection, sorption, and chemical reaction in a reactor and filtration with a fabric filter. The aim with this article is to evaluate the efficiency of the system to recover Hg in flue gases from boilers in routine operation. Flue gases, ashes, and water were sampled yearly for 21 years and analysed for Hg, dioxin, and other potential contaminants received at waste incineration. The results clearly demonstrate the decreasing use of Hg in society the last two decades as influenced by governmental policy regarding Hg. The results also indicate that the equipment efficiently removed Hg and dioxins from the flue gases to a final concentration of approximately 3.5 microg Hgm(-3) n and 0.01 ng dioxinsm(-3) n, corresponding to more than 97 and 99.9% reduction of Hg and dioxins, respectively, by cleaning in three stages. The electrostatic precipitators and Filsorption stages alone, with the scrubber in bypass, removed 90% of Hg in flue gases. Using the scrubber is motivated to remove acid components and additional Hg, but call for water separated after the condensers to be neutralised and cleaned, so that less than 5

  15. A robot system for evaluating plaque removal efficiency of toothbrushes in vitro.

    PubMed

    Ernst, C P; Willershausen, B; Driesen, G; Warren, P R; Hilfinger, P

    1997-07-01

    A robot system simulating three-dimensional brushing motions as a function of time has been developed. In association with a typodont and either artificial plaque or chromogenic stain, the robot system can be used to assess the plaque removal efficiency or the cleaning effectiveness of toothbrushes. In particular, the influence of different brush head designs of powered toothbrushes was examined. The study compared the plaque removal efficiency of a cup-shaped brush head (Braun Oral-B EB 5) and a modified brush head (Braun Oral-B EB 9) that incorporates longer filaments on the outer ring, designed for additional interdental penetration. A specially designed artificial plaque was applied to the plastic teeth of typodonts. Artificial teeth were cleaned by the robot system for a 2-minute period with a wet brush head without a dentifrice. The remaining plaque was assessed visually by two independent examiners, with a modification of the global Plaque Index. In comparison to the EB 5, the new brush head significantly reduced artificial plaque overall. In vitro data demonstrated the ability of the robot system to reveal reproducible significant differences of the cleaning effectiveness of powered toothbrushes.

  16. Dust Removal Technolgy for a Mars In Situ Resource Utilization System

    NASA Technical Reports Server (NTRS)

    Calle, C. I.; Johansen, M. R.; Williams, B. S.; Hogue, M. D.; Mackey, P. J.; Clements, J. S.

    2011-01-01

    Several In Situ Resource Utilization (lSRU) systems being considered to enable future manned exploration of Mars require capture of Martian atmospheric gas to extract oxygen and other commodities. However, the Martian atmosphere contains relatively large amounts of dust which must be removed in tbe collection systems of the ISRU chambers. The amount of atmospheric dust varies largely with the presence of daily dust devils and the less frequent but much more powerful global dust storms. A common and mature dust removal technology for terrestrial systems is the electrostatic precipitator. With this technology, dust particles being captured are imparted an electrostatic charge by means of a corona discharge. Charged dust particles are then driven to a region of high electric field which forces the particles onto a collector for capture. Several difficulties appear when this technology is adapted to the Martian atmospheric environment At the low atmospheric pressure of Mars, electrical breakdown occurs at much lower voltages than on Earth and corona discharge is difficult to sustain. In this paper, we report on our efforts to obtain a steady corona/glow discharge in a simulated Martian atmosphere of carbon dioxide at 9 millibars of pressure. We also present results on the design of a dust capture system under these atmospheric conditions.

  17. Could nitrite/free nitrous acid favour GAOs over PAOs in enhanced biological phosphorus removal systems?

    PubMed

    Pijuan, M; Ye, L; Yuan, Z

    2011-01-01

    Enhanced biological phosphorus removal (EBPR) normally occurs together with nitrogen removal in wastewater treatment plants (WWTPs). In recent years, efforts have been devoted to remove nitrogen via the nitrite pathway (oxidation of ammonia to nitrite and reduction of nitrite to nitrogen gas without going through nitrate), reducing the requirement for carbon and oxygen in the plant. However nitrite and free nitrous acid (FNA), the protonated species of nitrite, have been shown to cause EBPR deterioration under certain concentrations. This study provides a direct comparison between the different levels of FNA inhibition in the aerobic processes of polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) by reviewing the studies published in this area. Also, new data is presented assessing the FNA effect on the anaerobic metabolism of these two groups of bacteria. Overall, FNA has shown inhibitory effects on most of the processes involved in the metabolism of PAOs and GAOs. However, the inhibition-initiation levels are different between different processes and, even more importantly between the two groups. In general, PAOs appear to be more affected than GAOs at the same level of FNA, thus giving GAOs competitive advantage over PAOs in EBPR systems when nitrite is present.

  18. Effect of COD/N ratio on removal performances in two subsurface wastewater infiltration systems.

    PubMed

    Fei Jing Pan Deli Tong Linli Huang Long Yu Yafei Sun Shiyue Qi Yaoyao Huang, Hexin

    2017-01-24

    Dissolved oxygen (DO), removal of COD, TP and nitrogen in subsurface wastewater infiltration systems (SWISs)with/without intermittent aeration under different influent COD/N ratios were investigated. Aerobic conditions were effectively developed in 50 cm depth of the matrix and anoxic or anaerobic conditions were not changed in 80 and 110 cm depth by intermittent aeration, which encouraged nitrification. Increased influent COD/N ratio led to lower COD and nitrogen removal in conventional SWISs. Sufficient carbon source in high COD/N ratio influent promoted denitrification with intermittent aeration. High removal rates of COD (95.68±0.21%), TP (92.02±0.28%), NH4+-N (99.33±0.05%) and TN (89.65±0.6%) were obtained with influent COD/N ratio of 12 in aerated SWISs. Under the COD/N ratio of 12 and 18, intermittent aeration boosted the growth and reproduction of nitrifying bacteria and denitrifying bacteria. Meanwhile, nitrate and nitrite reductase activities with intermittent aeration were higher than that without aeration in 80 and 110 cm depth.

  19. Removal of heavy metals from fly ash leachate using combined bioelectrochemical systems and electrolysis.

    PubMed

    Tao, Hu-Chun; Lei, Tao; Shi, Gang; Sun, Xiao-Nan; Wei, Xue-Yan; Zhang, Li-Juan; Wu, Wei-Min

    2014-01-15

    Based on environmental and energetic analysis, a novel combined approach using bioelectrochemical systems (BES) followed by electrolysis reactors (ER) was tested for heavy metals removal from fly ash leachate, which contained high detectable levels of Zn, Pb and Cu according to X-ray diffraction analysis. Acetic acid was used as the fly ash leaching agent and tested under various leaching conditions. A favorable condition for the leaching process was identified to be liquid/solid ratio of 14:1 (w/w) and leaching duration 10h at initial pH 1.0. It was confirmed that the removal of heavy metals from fly ash leachate with the combination of BESs and ER is feasible. The metal removal efficiency was achieved at 98.5%, 95.4% and 98.1% for Cu(II), Zn(II), and Pb(II), respectively. Results of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) indicated that Cu(II) was reduced and recovered mainly as metal Cu on cathodes related to power production, while Zn(II) and Pb(II) were not spontaneously reduced in BESs without applied voltage and basically electrolyzed in the electrolysis reactors.

  20. Phosphorus removal coupled to bioenergy production by three cyanobacterial isolates in a biofilm dynamic growth system.

    PubMed

    Gismondi, Alessandra; Pippo, Francesca Di; Bruno, Laura; Antonaroli, Simonetta; Congestri, Roberta

    2016-09-01

    In the present study a closed incubator, designed for biofilm growth on artificial substrata, was used to grow three isolates of biofilm-forming heterocytous cyanobacteria using an artificial wastewater secondary effluent as the culture medium. We evaluated biofilm efficiency in removing phosphorus, by simulating biofilm-based tertiary wastewater treatment and coupled this process with biodiesel production from the developed biomass. The three strains were able to grow in the synthetic medium and remove phosphorus in percentages, between 6 and 43%, which varied between strains and also among each strain according to the biofilm growth phase. Calothrix sp. biofilm turned out to be a good candidate for tertiary treatment, showing phosphorus reducing capacity (during the exponential biofilm growth) at the regulatory level for the treated effluent water being discharged into natural water systems. Besides phosphorus removal, the three cyanobacterial biofilms produced high quality lipids, whose profile showed promising chemical stability and combustion behavior. Further integration of the proposed processes could include the integration of oil extracted from these cyanobacterial biofilms with microalgal oil known for high monounsaturated fatty acids content, in order to enhance biodiesel cold flow characteristics.

  1. Microbial nitrogen removal pathways in integrated vertical-flow constructed wetland systems.

    PubMed

    Hu, Yun; He, Feng; Ma, Lin; Zhang, Yi; Wu, Zhenbin

    2016-05-01

    Microbial nitrogen (N) removal pathways in planted (Canna indica L.) and unplanted integrated vertical-flow constructed wetland systems (IVCWs) were investigated. Results of, molecular biological and isotope pairing experiments showed that nitrifying, anammox, and denitrifying bacteria were distributed in both down-flow and up-flow columns of the IVCWs. Further, the N transforming bacteria in the planted IVCWs were significantly higher than that in the unplanted ones (p<0.05). Moreover, the potential nitrification, anammox, and denitrification rates were highest (18.90, 11.75, and 7.84nmolNg(-1)h(-1), respectively) in the down-flow column of the planted IVCWs. Significant correlations between these potential rates and the absolute abundance of N transformation genes further confirmed the existence of simultaneous nitrification, anammox, and denitrification (SNAD) processes in the IVCWs. The anammox process was the major N removal pathway (55.6-60.0%) in the IVCWs. The results will further our understanding of the microbial N removal mechanisms in IVCWs.

  2. Hollow-Fiber Cartridges: Model Systems for Virus Removal from Blood

    NASA Astrophysics Data System (ADS)

    Jacobitz, Frank; Menon, Jeevan

    2005-11-01

    Aethlon Medical is developing a hollow-fiber hemodialysis device designed to remove viruses and toxins from blood. Possible target viruses include HIV and pox-viruses. The filter could reduce virus and viral toxin concentration in the patient's blood, delaying illness so the patient's immune system can fight off the virus. In order to optimize the design of such a filter, the fluid mechanics of the device is both modeled analytically and investigated experimentally. The flow configuration of the proposed device is that of Starling flow. Polysulfone hollow-fiber dialysis cartridges were used. The cartridges are charged with water as a model fluid for blood and fluorescent latex beads are used in the experiments as a model for viruses. In the experiments, properties of the flow through the cartridge are determined through pressure and volume flow rate measurements of water. The removal of latex beads, which are captured in the porous walls of the fibers, was measured spectrophotometrically. Experimentally derived coefficients derived from these experiments are used in the analytical model of the flow and removal predictions from the model are compared to those obtained from the experiments.

  3. Hydraulic and pollutant removal performance of fine media stormwater filtration systems.

    PubMed

    Hatt, Belinda E; Fletcher, Tim D; Deletic, Ana

    2008-04-01

    Stormwater runoff from urban areas has multiple negative hydrologic and ecological impacts for receiving waters. Fine media stormwater filtration systems have the potential to mitigate these effects, through flow attenuation and pollutant removal. This work provides an overall assessment of the hydraulic and pollutant removal behavior of sand- and soil-based stormwater filters at the laboratory scale. The influence of time, cumulative inflow sediment, cumulative water volume, wetting and drying, and compaction on hydraulic capacity was investigated. The results suggested that the primary cause of hydraulic failure was formation of a clogging layer at the filter surface. Loads of sediment and heavy metals were effectively retained; however,the soil-based filters leached nitrogen and phosphorus for the duration of the experimental period. Media pollutant profiles revealed significant accumulation of all pollutants in the top 20% of the filter profile, suggesting that elevated discharges of nutrients was due to leaching of native material, rather than failure to remove incoming pollutants. It is recommended that the top 2-5 cm of the filter surface be scraped off every two years to prevent hydraulic failure; this will also avoid excessive accumulation of heavy metals, which may otherwise have been of concern.

  4. Contaminant Removal from Oxygen Production Systems for In Situ Resource Utilization

    NASA Technical Reports Server (NTRS)

    Anthony, Stephen M.; Santiago-Maldonado, Edgardo; Captain, James G.; Pawate, Ashtamurthy S.; Kenis, Paul J. A.

    2012-01-01

    The In Situ Resource Utilization (ISRU) project has been developing technologies to produce oxygen from lunar regolith to provide consumables to a lunar outpost. The processes developed reduce metal oxides in the regolith to produce water, which is then electrolyzed to produce oxygen. Hydrochloic and hydrofluoric acids are byproducts of the reduction processes, as halide minerals are also reduced at oxide reduction conditions. Because of the stringent water quality requirements for electrolysis, there is a need for a contaminant removal process. The Contaminant Removal from Oxygen Production Systems (CROPS) team has been developing a separation process to remove these contaminants in the gas and liquid phase that eliminates the need for consumables. CROPS has been using Nafion, a highly water selective polymeric proton exchange membrane, to recover pure water from the contaminated solution. Membrane thickness, product stream flow rate, and acid solution temperature and concentration were varied with the goal of maximizing water permeation and acid rejection. The results show that water permeation increases with increasing solution temperature and product stream flow rate, while acid rejection increases with decreasing solution temperature and concentration. Thinner membranes allowed for higher water flux and acid rejection than thicker ones. These results were used in the development of the hardware built for the most recent Mars ISRU demonstration project.

  5. Horizontal Heat Exchanger Design and Analysis for Passive Heat Removal Systems

    SciTech Connect

    Vierow, Karen

    2005-08-29

    This report describes a three-year project to investigate the major factors of horizontal heat exchanger performance in passive containment heat removal from a light water reactor following a design basis accident LOCA (Loss of Coolant Accident). The heat exchanger studied in this work may be used in advanced and innovative reactors, in which passive heat removal systems are adopted to improve safety and reliability The application of horizontal tube-bundle condensers to passive containment heat removal is new. In order to show the feasibility of horizontal heat exchangers for passive containment cooling, the following aspects were investigated: 1. the condensation heat transfer characteristics when the incoming fluid contains noncondensable gases 2. the effectiveness of condensate draining in the horizontal orientation 3. the conditions that may lead to unstable condenser operation or highly degraded performance 4. multi-tube behavior with the associated secondary-side effects This project consisted of two experimental investigations and analytical model development for incorporation into industry safety codes such as TRAC and RELAP. A physical understanding of the flow and heat transfer phenomena was obtained and reflected in the analysis models. Two gradute students (one funded by the program) and seven undergraduate students obtained research experience as a part of this program.

  6. Application of bacteriophages to selectively remove Pseudomonas aeruginosa in water and wastewater filtration systems.

    PubMed

    Zhang, Yanyan; Hunt, Heather K; Hu, Zhiqiang

    2013-09-01

    Water and wastewater filtration systems often house pathogenic bacteria, which must be removed to ensure clean, safe water. Here, we determine the persistence of the model bacterium Pseudomonas aeruginosa in two types of filtration systems, and use P. aeruginosa bacteriophages to determine their ability to selectively remove P. aeruginosa. These systems used beds of either anthracite or granular activated carbon (GAC), which were operated at an empty bed contact time (EBCT) of 45 min. The clean bed filtration systems were loaded with an instantaneous dose of P. aeruginosa at a total cell number of 2.3 (± 0.1 [standard deviation]) × 10(7) cells. An immediate dose of P. aeruginosa phages (1 mL of phage stock at the concentration of 2.7 × 10(7) PFU (Plaque Forming Units)/mL) resulted in a reduction of 50% (± 9%) and >99.9% in the effluent P. aeruginosa concentrations in the clean anthracite and GAC filters, respectively. To further evaluate the effects of P. aeruginosa phages, synthetic stormwater was run through anthracite and GAC biofilters where mixed-culture biofilms were present. Eighty five days after an instantaneous dose of P. aeruginosa (2.3 × 10(7) cells per filter) on day 1, 7.5 (± 2.8) × 10(7) and 1.1 (± 0.5) × 10(7) P. aeruginosa cells/g filter media were detected in the top layer (close to the influent port) of the anthracite and GAC biofilters, respectively, demonstrating the growth and persistence of pathogenic bacteria in the biofilters. A subsequent 1-h dose of phages, at the concentration of 5.1 × 10(6) PFU/mL and flow rate of 1.6 mL/min, removed the P. aeruginosa inside the GAC biofilters and the anthracite biofilters by 70% (± 5%) and 56% (± 1%), respectively, with no P. aeruginosa detected in the effluent, while not affecting ammonia oxidation or the ammonia-oxidizing bacterial community inside the biofilters. These results suggest that phage treatment can selectively remove pathogenic bacteria with minimal impact on beneficial

  7. Enhanced Cr(VI) removal from groundwater by Fe(0)-H2O system with bio-amended iron corrosion.

    PubMed

    Yin, Weizhao; Li, Yongtao; Wu, Jinhua; Chen, Guocai; Jiang, Gangbiao; Li, Ping; Gu, Jingjing; Liang, Hao; Liu, Chuansheng

    2017-02-27

    A one-pot bio-iron system was established to investigate synergetic abiotic and biotic effects between iron and microorganisms on Cr(VI) removal. More diverse iron corrosion and reactive solids, such as green rusts, lepidocrocite and magnetite were found in the bio-iron system than in the Fe(0)-H2O system, leading to 4.3 times higher Cr(VI) removal efficiency in the bio-iron system than in the Fe(0)-H2O system. The cycling experiment also showed that the Cr(VI) removal capacity of Fe(0) in the bio-iron system was 12.4 times higher than that in the Fe(0)-H2O system. A 62days of life-span could be achieved in the bio-iron system, while the Fe(0)-H2O system lost its efficacy after 30days. Enhanced effects of extra Fe(2+) on Cr(VI) removal was observed, largely contributed to the adsorbed Fe(2+) on iron surface, which could function as an extra reductant for Cr(VI) and promote the electron transfer on the solid phase. The results also showed that the reduction of Cr(VI) by microorganisms was insignificant, indicating the adsorption/co-precipitation of Cr by iron oxides on iron surface was responsible for the overall Cr(VI) removal. Our study demonstrated that the bio-amended iron corrosion could improve the performance of Fe(0) for Cr(VI) removal from groundwater.

  8. Potential for water salvage by removal of non-native woody vegetation from dryland river systems

    USGS Publications Warehouse

    Doody, T.M.; Nagler, P.L.; Glenn, E.P.; Moore, G.W.; Morino, K.; Hultine, K.R.; Benyon, R.G.

    2011-01-01

    Globally, expansion of non-native woody vegetation across floodplains has raised concern of increased evapotranspiration (ET) water loss with consequent reduced river flows and groundwater supplies. Water salvage programs, established to meet water supply demands by removing introduced species, show little documented evidence of program effectiveness. We use two case studies in the USA and Australia to illustrate factors that contribute to water salvage feasibility for a given ecological setting. In the USA, saltcedar (Tamarix spp.) has become widespread on western rivers, with water salvage programs attempted over a 50-year period. Some studies document riparian transpiration or ET reduction after saltcedar removal, but detectable increases in river base flow are not conclusively shown. Furthermore, measurements of riparian vegetation ET in natural settings show saltcedar ET overlaps the range measured for native riparian species, thereby constraining the possibility of water salvage by replacing saltcedar with native vegetation. In Australia, introduced willows (Salix spp.) have become widespread in riparian systems in the Murray-Darling Basin. Although large-scale removal projects have been undertaken, no attempts have been made to quantify increases in base flows. Recent studies of ET indicate that willows growing in permanently inundated stream beds have high transpiration rates, indicating water savings could be achieved from removal. In contrast, native Eucalyptus trees and willows growing on stream banks show similar ET rates with no net water salvage from replacing willows with native trees. We conclude that water salvage feasibility is highly dependent on the ecohydrological setting in which the non-native trees occur. We provide an overview of conditions favorable to water salvage. Copyright ?? 2011 John Wiley & Sons, Ltd.

  9. Natural circulation decay heat removal from an SP-100, 550 kWe power system for a lunar outpost

    NASA Technical Reports Server (NTRS)

    El-Genk, Mohamed S.; Xue, Huimin

    1992-01-01

    This research investigated the decay heat removal from the SP-100 reactor core of a 550-kWe power system for a lunar outpost by natural circulation of lithium coolant. A transient model that simulates the decay heat removal loop (DHRL) of the power system was developed and used to assess the system's decay heat removal capability. The effects of the surface area of the decay heat rejection radiator, the dimensions of the decay heat exchanger (DHE) flow duct, the elevation of the DHE, and the diameter of the rise and down pipes in the DHRL on the decay heat removal capability were examined. Also, to determine the applicability of test results at earth gravity to actual system performance on the lunar surface, the effect of the gravity constant (1 g and 1/6 g) on the thermal behavior of the system after shutdown was investigated.

  10. The state of the art of removal of prion proteins in SD-FFP, by specific prion affinity chromatography and its impact on the hemostatic characteristics of the product.

    PubMed

    Neisser-Svae, Andrea; Seghatchian, Jerard

    2015-04-01

    In recent Coimbra' Conference, on the pre-launch of pathogen reduced-FFP for the local clinical use, the question was raised, by the moderator, on the efficacy of the current methodology used for prion removal processes and its influence on the overall quality and safety of the final product. This brief paper put together by speaker of this session and the moderator, as a consensus of opinions, which was largely discussed during Q&A session, to make it available to a large group of readers of transfusion apheresis science, who might be interested to this topic. In short the capacity of the current process of Octaplas to remove prion is in order of 5.6 log10/ID50 reduction based on several animal studies. Moreover the changes in coagulation and inhibitors are within acceptable range and bioequivalent to untreated FFP with no sign of inferiority. This paper describes in brief a technology update on solvent/detergent treated plasma, an alternative to FFP but with increased pathogen safety. The biochemical profile of the final product is comparable with FFP and contains all clinically relevant plasma proteins. Furthermore, Octaplas is a product that, in long term, reduces health care costs.

  11. Expression and affinity purification of recombinant proteins from plants

    NASA Technical Reports Server (NTRS)

    Desai, Urvee A.; Sur, Gargi; Daunert, Sylvia; Babbitt, Ruth; Li, Qingshun

    2002-01-01

    With recent advances in plant biotechnology, transgenic plants have been targeted as an inexpensive means for the mass production of proteins for biopharmaceutical and industrial uses. However, the current plant purification techniques lack a generally applicable, economic, large-scale strategy. In this study, we demonstrate the purification of a model protein, beta-glucuronidase (GUS), by employing the protein calmodulin (CaM) as an affinity tag. In the proposed system, CaM is fused to GUS. In the presence of calcium, the calmodulin fusion protein binds specifically to a phenothiazine-modified surface of an affinity column. When calcium is removed with a complexing agent, e.g., EDTA, calmodulin undergoes a conformational change allowing the dissociation of the calmodulin-phenothiazine complex and, therefore, permitting the elution of the GUS-CaM fusion protein. The advantages of this approach are the fast, efficient, and economical isolation of the target protein under mild elution conditions, thus preserving the activity of the target protein. Two types of transformation methods were used in this study, namely, the Agrobacterium-mediated system and the viral-vector-mediated transformation system. Copyright 2002 Elsevier Science (USA).

  12. Coupled BAS and anoxic USB system to remove urea and formaldehyde from wastewater.

    PubMed

    Campos, J L; Sánchez, M; Mosquera-Corral, A; Méndez, R; Lema, J M

    2003-08-01

    Wastewater containing formaldehyde and urea was treated using a coupled system consisting of a biofilm airlift suspension (BAS) reactor and an anoxic upflow sludge blanket (USB) reactor. The anoxic USB reactor was used to carry out denitrification and urea hydrolysis, while the BAS reactor was used to carry out nitrification. In a first step, individual experiments were carried out to investigate the effects of both compounds on the nitrifying and denitrifying biomass. The BAS reactor was fed with a synthetic medium containing 500 mg N-NH4(+)l(-1) and 100mg N-urea l(-1), that were added continuously to this medium. Neither urea hydrolysis nor inhibition of nitrification was observed. Nitrification efficiency decreased when formaldehyde was fed during shocks at concentrations of 40, 80 and 120 mg C-formaldehyde l(-1). The anoxic USB reactor was fed with a synthetic medium containing nitrate, formaldehyde and urea. Concentrations of formaldehyde in the reactor of 100-120 mg C-formaldehyde l(-1) caused a decrease in the denitrification and urea hydrolysis rates. In a second step, the coupled system was operated at recycling ratios (R) of 3 and 9. Fed C/N ratios of 0.58, 1.0 and 1.5 g C-formaldehyde g(-1) N-NH4(+) were used for every recycling ratio. The maximum nitrogen removal percentages were achieved at a C/N ratio of 1.0 g C-formaldehyde g(-1) N-NH4(+) for both recycling ratios. A fed C/N ratio of 1.5 g C-formaldehyde g(-1) N-NH4(+) caused a decrease in the efficiency of the system with respect to nitrogen removal, due to the presence of formaldehyde in the BAS reactor, which decreased the nitrification. Formaldehyde was completely removed in the BAS reactor and a heterotrophic layer formed around the nitrifying biofilm.

  13. N-terminal processing of affinity-tagged recombinant proteins purified by IMAC procedures.

    PubMed

    Mooney, Jane T; Fredericks, Dale P; Christensen, Thorkild; Bruun Schiødt, Christine; Hearn, Milton T W

    2015-07-01

    The ability of a new class of metal binding tags to facilitate the purification of recombinant proteins, exemplified by the tagged glutathione S-transferase and human growth hormone, from Escherichia coli fermentation broths and lysates has been further investigated. These histidine-containing tags exhibit high affinity for borderline metal ions chelated to the immobilised ligand, 1,4,7-triazacyclononane (tacn). The use of this tag-tacn immobilised metal ion affinity chromatography (IMAC) system engenders high selectivity with regard to host cell protein removal and permits facile tag removal from the E. coli-expressed recombinant protein. In particular, these tags were specifically designed to enable their efficient removal by the dipeptidyl aminopeptidase 1 (DAP-1), thus capturing the advantages of high substrate specificity and rates of cleavage. MALDI-TOF MS analysis of the cleaved products from the DAP-1 digestion of the recombinant N-terminally tagged proteins confirmed the complete removal of the tag within 4-12 h under mild experimental conditions. Overall, this study demonstrates that the use of tags specifically designed to target tacn-based IMAC resins offers a comprehensive and flexible approach for the purification of E. coli-expressed recombinant proteins, where complete removal of the tag is an essential prerequisite for subsequent application of the purified native proteins in studies aimed at delineating the molecular and cellular basis of specific biological processes.

  14. Nitrogen removal during leachate treatment: comparison of simple and sophisticated systems.

    PubMed

    Vasel, J L; Jupsin, H; Annachhatre, A P

    2004-01-01

    Membrane bioreactors (MBR) have become common in treating municipal wastewaters. Applied to leachates treatment MBR were also successful with pilot scale experiments and full-scale facilities as well. We succeeded previously in designing an efficient nitrification-denitrification process with an ethylene glycol byproduct as carbon source for denitrification. Moreover, an unexpectedly high inert COD removal efficiency was also observed in the full-scale MBR facility thereby making it possible to increase the operating time of the final GAC (Granulated Activated Carbon) adsorber. Since MBR are very sophisticated systems. Simpler and "lower" cost systems can also be considered. For example it is possible to nitrify leachates from sanitary landfill using a simple infiltration-percolation technique with a low energy cost. To validate previously published laboratory experiments, a semi industrial-scale pilot installation was installed at the Montzen landfill site (Belgium). The process is based on infiltration-percolation through a granular bed. This well known process was modified to increase the load, notably by changing the support medium, adding an electric fan that is run intermittently and maintaining temperatures greater than 15 degrees C. The new material is a type of granular calcium carbonate with a large specific surface area. These technical improvements enabled the system to nitrify up to 0.4 kg NH4+-N/m3 of reactor bed per day at a hydraulic load of 0.35 m.d(-1), with an ammonia removal rate in the range of 80 to 95%. Despite the high ammonia nitrogen inlet concentrations, this system exhibits remarkable nitrification efficiency. Moreover, these performances are achieved in a batch mode system without recirculation or dilution processes. If complete nitrification is needed, it can be obtained in a second in series of bioreactors. The system can be classified as a low cost process. An international patent is pending. Possible performances of those systems

  15. Motion artifact removal algorithm by ICA for e-bra: a women ECG measurement system

    NASA Astrophysics Data System (ADS)

    Kwon, Hyeokjun; Oh, Sechang; Varadan, Vijay K.

    2013-04-01

    Wearable ECG(ElectroCardioGram) measurement systems have increasingly been developing for people who suffer from CVD(CardioVascular Disease) and have very active lifestyles. Especially, in the case of female CVD patients, several abnormal CVD symptoms are accompanied with CVDs. Therefore, monitoring women's ECG signal is a significant diagnostic method to prevent from sudden heart attack. The E-bra ECG measurement system from our previous work provides more convenient option for women than Holter monitor system. The e-bra system was developed with a motion artifact removal algorithm by using an adaptive filter with LMS(least mean square) and a wandering noise baseline detection algorithm. In this paper, ICA(independent component analysis) algorithms are suggested to remove motion artifact factor for the e-bra system. Firstly, the ICA algorithms are developed with two kinds of statistical theories: Kurtosis, Endropy and evaluated by performing simulations with a ECG signal created by sgolayfilt function of MATLAB, a noise signal including 0.4Hz, 1.1Hz and 1.9Hz, and a weighed vector W estimated by kurtosis or entropy. A correlation value is shown as the degree of similarity between the created ECG signal and the estimated new ECG signal. In the real time E-Bra system, two pseudo signals are extracted by multiplying with a random weighted vector W, the measured ECG signal from E-bra system, and the noise component signal by noise extraction algorithm from our previous work. The suggested ICA algorithm basing on kurtosis or entropy is used to estimate the new ECG signal Y without noise component.

  16. Predicting binding affinities of host-guest systems in the SAMPL3 blind challenge: the performance of relative free energy calculations

    NASA Astrophysics Data System (ADS)

    König, Gerhard; Brooks, Bernard R.

    2012-05-01

    Relative free energy calculations based on molecular dynamics simulations are combined with available experimental binding free energies to predict unknown binding affinities of acyclic Cucurbituril complexes in the blind SAMPL3 competition. The predictions yield root mean square errors between 2.6 and 3.2 kcal/mol for seven host-guest systems. Those deviations are comparable to results for solvation free energies of small organic molecules. However, the standard deviations found in our simulations range from 0.4 to 2.4 kcal/mol, which indicates the need for better sampling. Three different approaches are compared. Bennett's Acceptance Ratio Method and thermodynamic integration based on the trapezoidal rule with 12 λ-points exhibit a root mean square error of 2.6 kcal/mol, while thermodynamic integration with Simpson's rule and 11 λ-points leads to a root mean square error of 3.2 kcal/mol. In terms of absolute median errors, Bennett's Acceptance Ratio Method performs better than thermodynamic integration with the trapezoidal rule (1.7 vs. 2.9 kcal/mol). Simulations of the deprotonated forms of the guest molecules exhibit a poorer correspondence to experimental results with a root mean square error of 5.2 kcal/mol. In addition, a decrease of the buffer concentration by approximately 20 mM in the simulations raises the root mean square error to 3.8 kcal/mol.

  17. Predicting binding affinities of host-guest systems in the SAMPL3 blind challenge: the performance of relative free energy calculations.

    PubMed

    König, Gerhard; Brooks, Bernard R

    2012-05-01

    Relative free energy calculations based on molecular dynamics simulations are combined with available experimental binding free energies to predict unknown binding affinities of acyclic Cucurbituril complexes in the blind SAMPL3 competition. The predictions yield root mean square errors between 2.6 and 3.2 kcal/mol for seven host-guest systems. Those deviations are comparable to results for solvation free energies of small organic molecules. However, the standard deviations found in our simulations range from 0.4 to 2.4 kcal/mol, which indicates the need for better sampling. Three different approaches are compared. Bennett's Acceptance Ratio Method and thermodynamic integration based on the trapezoidal rule with 12 λ-points exhibit a root mean square error of 2.6 kcal/mol, while thermodynamic integration with Simpson's rule and 11 λ-points leads to a root mean square error of 3.2 kcal/mol. In terms of absolute median errors, Bennett's Acceptance Ratio Method performs better than thermodynamic integration with the trapezoidal rule (1.7 vs. 2.9 kcal/mol). Simulations of the deprotonated forms of the guest molecules exhibit a poorer correspondence to experimental results with a root mean square error of 5.2 kcal/mol. In addition, a decrease of the buffer concentration by approximately 20 mM in the simulations raises the root mean square error to 3.8 kcal/mol.

  18. Arsenic removal by discontinuous ZVI two steps system for drinking water production at household scale.

    PubMed

    Casentini, Barbara; Falcione, Fabiano Teo; Amalfitano, Stefano; Fazi, Stefano; Rossetti, Simona

    2016-12-01

    Different countries in Europe still suffer of elevated arsenic (As) concentration in groundwaters used for human consumption. In the case of households not connected to the distribution system, decentralized water supply systems, such as Point of Use (POU) and Point of Entry (POE), offer a direct benefit for the consumers. Field scale ex-situ treatment systems based on metallic iron (ZVI) are already available for the production of reduced volumes of drinking water in remote areas (village scale). To address drinking water needs at larger scale, we designed a pilot unit able to produce an elevated daily volume of water for human consumption. We tested the long-term As removal efficiency of a two steps ZVI treatment unit for the production of 400 L/day clean water based on the combination of ZVI corrosion process with sedimentation and retention of freshly formed Fe precipitates. The system treated 100 μg/L As(V)-contaminated oxic groundwater in a discontinuous operation mode at a flow rate of 1 L/min for 31 days. Final removal was 77-96% and the most performing step was aeration/sedimentation (A/S) tank with a 60-94% efficiency. Arsenic in the outflow slightly exceeded the drinking water limit of 10 μg/L only after 6000 L treated and Fe concentration was always below 0.2 mg/L. Under proposed operating conditions ZVI passivation readily occurred and, as a consequence, Fe production sharply decreased. Arsenic mobility attached to particulate was 13-60% after ZVI column and 37-100% after A/S tank. Uniform amorphous cluster of Fe nanoparticles (100 nm) formed during aeration drove As removal process with an adsorption capacity corresponding to 20.5 mgAs/gFe. Research studies often focus only on chemico-physical aspects disregarding the importance of biological processes that may co-occur and interfere with ZVI corrosion, As removal and safe water production. We explored the microbial transport dynamics by flow cytometry, proved as a suitable tool to monitor

  19. 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.

  20. Ultra-accuracy parallel electronic datum optical metrology system of systems (notice of removal)

    NASA Astrophysics Data System (ADS)

    Xiong, Xiang-Wen; Bear, Wynn L.; Roth, John T.; Schoen, Marco P.

    2008-03-01

    This paper (SPIE Paper 682925) was removed from the SPIE Digital Library on 19 August 2008 upon learning that two individuals listed as additional co-authors on the manuscript had no prior knowledge of the paper, did not contribute to it, and did not consent to having their names included as co-authors. The names of these two individuals have been or will be deleted from this and all other bibliographic records as far as possible since they have no connection to this paper. Additionally, the remaining names associated with this publication record, Xiang-Wen Xiong and Wynn L. Bear, are actually the same individual and not two different authors. This is not sanctioned by SPIE. As stated in the SPIE Guidelines for Professional Conduct and Publishing Ethics, "SPIE considers it the professional responsibility of all authors to ensure that the authorship of submitted papers properly reflects the contributions and consent of all authors." A serious violation of these guidelines is evident in this case. It is SPIE policy to remove papers from the SPIE Digital Library where serious professional misconduct has occurred and to impose additional sanctions as appropriate.

  1. Removal of trace organic contaminants by a membrane bioreactor-granular activated carbon (MBR-GAC) system.

    PubMed

    Nguyen, Luong N; Hai, Faisal I; Kang, Jinguo; Price, William E; Nghiem, Long D

    2012-06-01

    The removal of trace organics by a membrane bioreactor-granular activated carbon (MBR-GAC) integrated system were investigated. The results confirmed that MBR treatment can be effective for the removal of hydrophobic (log D>3.2) and readily biodegradable trace organics. The data also highlighted the limitation of MBR in removing hydrophilic and persistent compounds (e.g. carbamazepine, diclofenac, and fenoprop) and that GAC could complement MBR very well as a post-treatment process. The MBR-GAC system showed high removal of all selected trace organics including those that are hydrophilic and persistent to biological degradation at up to 406 bed volumes (BV). However, over an extended period, breakthrough of diclofenac was observed after 7320 BV. This suggests that strict monitoring should be applied over the lifetime of the GAC column to detect the breakthrough of hydrophilic and persistent compounds which have low removal by MBR treatment.

  2. Effects of aeration position on organics, nitrogen and phosphorus removal in combined oxidation pond-constructed wetland systems.

    PubMed

    Wang, Xiaoou; Tian, Yimei; Zhao, Xinhua; Peng, Sen; Wu, Qing; Yan, Lijian

    2015-12-01

    Given that few studies investigated the effects of aeration position (AP) on the performance of aerated constructed wetlands, the aim of this study was to evaluate the effects of AP on organics, nitrogen and phosphorus removal in lab-scale combined oxidation pond-constructed wetland (OP-CW) systems. Results showed that middle aeration allowed the CW to possess more uniform oxygen distribution and to achieve greater removals of COD and NH3-N, while the CW under bottom aeration and surface aeration demonstrated more distinct stratification of oxygen distribution and surface aeration brought about better TN removal capacity for the OP-CW system. However, no significant influence of artificial aeration or AP on TP removal was observed. Overall, AP could significantly affect the spatial distribution of dissolved oxygen by influencing the oxygen diffusion paths in aerated CWs, thereby influencing the removal of pollutants, especially organics and nitrogen, which offers a reference for the design of aerated CWs.

  3. Application of affinity aqueous two-phase systems for the fractionation of CD133(+) stem cells from human umbilical cord blood.

    PubMed

    González-González, Mirna; Rito-Palomares, Marco

    2015-03-01

    In a further attempt to establish a novel stem cell primary recovery strategy, the use of aqueous two-phase systems (ATPS) complemented with the use of antibodies (known as immunoaffinity ATPS) is explored in this work. This type of liquid-liquid extraction systems exploits antigen-antibody affinity and represents a novel and selective approach for the purification of stem cells. The proposed bioengineering strategies include the implementation of traditional [polyethylene glycol (PEG), dextran (DEX) and ficoll] and novel (Ucon) immunoaffinity ATPS to prove the viability of cluster of differentiation 133 (CD133(+) ) stem cells from human umbilical cord blood. Furthermore, the addition of the antibody is implemented to identify conditions under which contaminants and stem cells of interest concentrate in opposite phases. The objective of this work is to establish the initial basis for the development of a novel and scalable purification bioprocess for the selective recovery of CD133(+) stem cells employing immunoaffinity ATPS. The reported methodology allows a partitioning of 62% CD133(+) stem cells to the top phase of the ficoll 400,000-DEX 70,000 immunoaffinity ATPS. In PEG 8,000-DEX 500,000 and Ucon-DEX 75,000 systems, no difference was observed when compared with the conventional ATPS (without antibody addition), as the CD133 antibody does not have preference for the desired clean top phase. In all experiments, cell viability was at least 98% after ATPS recovery. This research highlights the challenges that must be addressed to allow the potential establishment of a separation process using immunoaffinity ATPS for the recovery and purification of stem cells.

  4. A new reactor for denitrification and micro-particle removal in recirculated aquaculture systems.

    PubMed

    Boley, A; Korshun, G; Boley, S; Jung-Schroers, V; Adamek, M; Steinhagen, D; Richter, S

    2017-03-01

    A 'membrane-denitrification' reactor (MDR) was developed and tested in a semi-technical recirculation aquaculture system in comparison to a double - without MDR - as reference system. The MDR consisted of a reactor with an ultrafiltration membrane unit for removal of micro-particles (e.g. sludge flocs, bacteria and parasites). Specific carrier material provided surfaces for biofilm growth in a fluidized bed reactor with ethanol as carbon source for denitrification. The continuous motion of these carriers cleaned the membrane surface. With online and laboratory measurements of water parameters and operational data the feasibility of the concept was verified. An advantage is that no chemicals are needed to clean the membranes. Examinations of the fish and water analyses proved an MDR can positively influence cortisol, as a stress marker, and the microflora of the aquatic system.

  5. Sixty Percent Conceptual Design Report: Enterprise Accountability System for Classified Removable Electronic Media

    SciTech Connect

    B. Gardiner; L.Graton; J.Longo; T.Marks, Jr.; B.Martinez; R. Strittmatter; C.Woods; J. Joshua

    2003-05-03

    Classified removable electronic media (CREM) are tracked in several different ways at the Laboratory. To ensure greater security for CREM, we are creating a single, Laboratory-wide system to track CREM. We are researching technology that can be used to electronically tag and detect CREM, designing a database to track the movement of CREM, and planning to test the system at several locations around the Laboratory. We focus on affixing ''smart tags'' to items we want to track and installing gates at pedestrian portals to detect the entry or exit of tagged items. By means of an enterprise database, the system will track the entry and exit of tagged items into and from CREM storage vaults, vault-type rooms, access corridors, or boundaries of secure areas, as well as the identity of the person carrying an item. We are considering several options for tracking items that can give greater security, but at greater expense.

  6. A region finding method to remove the noise from the images of the human hand gesture recognition system

    NASA Astrophysics Data System (ADS)

    Khan, Muhammad Jibran; Mahmood, Waqas

    2015-12-01

    The performance of the human hand gesture recognition systems depends on the quality of the images presented to the system. Since these systems work in real time environment the images may be corrupted by some environmental noise. By removing the noise the performance of the system can be enhanced. So far different noise removal methods have been presented in many researches to eliminate the noise but all have its own limitations. We have presented a region finding method to deal with the environmental noise that gives better results and enhances the performance of the human hand gesture recognition systems so that the recognition rate of the system can be improved.

  7. Breadboard wash water renovation system. [using ferric chloride and ion exchange resins to remove soap and dissolved salts

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A total wash water renovation system concept was developed for removing objectionable materials from spacecraft wash water in order to make the water reusable. The breadboard model system described provides for pretreatment with ferric chloride to remove soap by chemical precipitation, carbon adsorption to remove trace dissolved organics, and ion exchange for removal of dissolved salts. The entire system was put into continuous operation and carefully monitored to assess overall efficiency and equipment maintenance problems that could be expected in actual use. In addition, the capacity of the carbon adsorbers and the ion-exchange resin was calculated and taken into consideration in the final evaluation of the system adequacy. The product water produced was well within the Tentative Wash Water Standards with regard to total organic carbon, conductivity, urea content, sodium chloride content, color, odor, and clarity.

  8. ETV REPORT: REMOVAL OF CHEMICAL CONTAMINANTS IN DRINKING WATER — PALL/KINETICO PUREFECTA DRINKING WATER TREATMENT SYSTEM

    EPA Science Inventory

    The Pall/Kinetico Purefecta™ POU drinking water treatment system was tested for removal of aldicarb, benzene, cadmium, carbofuran, cesium, chloroform, dichlorvos, dicrotophos, fenamiphos, mercury, mevinphos, oxamyl, strontium, and strychnine. The Purefecta™ employs several compon...

  9. The Development of a Parameterized Scatter Removal Algorithm for Nuclear Materials Identification System Imaging

    SciTech Connect

    Grogan, Brandon Robert

    2010-03-01

    This dissertation presents a novel method for removing scattering effects from Nuclear Materials Identification System (NMIS) imaging. The NMIS uses fast neutron radiography to generate images of the internal structure of objects non-intrusively. If the correct attenuation through the object is measured, the positions and macroscopic cross-sections of features inside the object can be determined. The cross sections can then be used to identify the materials and a 3D map of the interior of the object can be reconstructed. Unfortunately, the measured attenuation values are always too low because scattered neutrons contribute to the unattenuated neutron signal. Previous efforts to remove the scatter from NMIS imaging have focused on minimizing the fraction of scattered neutrons which are misidentified as directly transmitted by electronically collimating and time tagging the source neutrons. The parameterized scatter removal algorithm (PSRA) approaches the problem from an entirely new direction by using Monte Carlo simulations to estimate the point scatter functions (PScFs) produced by neutrons scattering in the object. PScFs have been used to remove scattering successfully in other applications, but only with simple 2D detector models. This work represents the first time PScFs have ever been applied to an imaging detector geometry as complicated as the NMIS. By fitting the PScFs using a Gaussian function, they can be parameterized and the proper scatter for a given problem can be removed without the need for rerunning the simulations each time. In order to model the PScFs, an entirely new method for simulating NMIS measurements was developed for this work. The development of the new models and the codes required to simulate them are presented in detail. The PSRA was used on several simulated and experimental measurements and chi-squared goodness of fit tests were used to compare the corrected values to the ideal values that would be expected with no scattering. Using

  10. THE DEVELOPMENT OF A PARAMETERIZED SCATTER REMOVAL ALGORITHM FOR NUCLEAR MATERIALS IDENTIFICATION SYSTEM IMAGING

    SciTech Connect

    Grogan, Brandon R

    2010-05-01

    This report presents a novel method for removing scattering effects from Nuclear Materials Identification System (NMIS) imaging. The NMIS uses fast neutron radiography to generate images of the internal structure of objects nonintrusively. If the correct attenuation through the object is measured, the positions and macroscopic cross sections of features inside the object can be determined. The cross sections can then be used to identify the materials, and a 3D map of the interior of the object can be reconstructed. Unfortunately, the measured attenuation values are always too low because scattered neutrons contribute to the unattenuated neutron signal. Previous efforts to remove the scatter from NMIS imaging have focused on minimizing the fraction of scattered neutrons that are misidentified as directly transmitted by electronically collimating and time tagging the source neutrons. The parameterized scatter removal algorithm (PSRA) approaches the problem from an entirely new direction by using Monte Carlo simulations to estimate the point scatter functions (PScFs) produced by neutrons scattering in the object. PScFs have been used to remove scattering successfully in other applications, but only with simple 2D detector models. This work represents the first time PScFs have ever been applied to an imaging detector geometry as complicated as the NMIS. By fitting the PScFs using a Gaussian function, they can be parameterized, and the proper scatter for a given problem can be removed without the need for rerunning the simulations each time. In order to model the PScFs, an entirely new method for simulating NMIS measurements was developed for this work. The development of the new models and the codes required to simulate them are presented in detail. The PSRA was used on several simulated and experimental measurements, and chi-squared goodness of fit tests were used to compare the corrected values to the ideal values that would be expected with no scattering. Using the

  11. The Use of Reactive Materials in Septic Systems for Pathogens and Nitrate Removal

    NASA Astrophysics Data System (ADS)

    Suhogusoff, A. V.; Hirata, R.; Aravena, R.; Stimson, J.; Robertson, W.

    2009-05-01

    The developing countries have an urgent need for cheap and efficient techniques for the improvement of sanitary conditions in areas without public water supply and sewerage system, especially in suburban regions or irregular occupation areas, where there is a great lack of social assistance. In this type of situations, the inhabitants use dug wells for water use and cesspits for disposal of sewage, which usually contaminates the groundwater with nitrate and microorganisms. As part of a study aiming to develop new sewage treatment systems in an irregular occupation area located at the District of Barragem, south region of the municipality of São Paulo (Brazil), a conventional cesspit (named as "Control") and an alternative septic system were constructed and monitored for a year. The design of the alternative septic system included a 1m thickness reactive barrier constituted by BOF (Budget Oxygen Furnace - a byproduct of the steel-making industry) for pathogens removal, then 1m sand package where the wastewater is oxidized and at the bottom the wastewater is in contact with a 0,5m thickness reactive barrier constituted by sawdust (carbon source), where redox conditions are very reducing and denitrification and even methanogenesis can take place. The chemical and biological data collected in the alternative septic system showed complete removal of the pathogens in the BOF barrier, then nitrification occurred between the BOF and the bottom of sand package. However denitrification in the sawdust barrier was incomplete because of the high pH caused by the BOF materials, which can reduced the number of denitrifiers bacteria present in the sawdust barrier. Isotope analyses that are been carried out in the residual nitrate will provided more information about the extent of the denitrification reaction in the alternative septic system. In case of the control cesspit, it was observed the occurrence of high concentration of ammonium, dissolved organic carbon, CO2, CH4 and low

  12. Nitrate and ammonium ions removal from groundwater by a hybrid system of zero-valent iron combined with adsorbents.

    PubMed

    Ji, Min-Kyu; Park, Won-Bae; Khan, Moonis Ali; Abou-Shanab, Reda A I; Kim, Yongje; Cho, Yunchul; Choi, Jaeyoung; Song, Hocheol; Jeon, Byong-Hun

    2012-04-01

    Nitrate (NO(3)(-)) is a commonly found contaminant in groundwater and surface water. It has created a major water quality problem worldwide. The laboratory batch experiments were conducted to investigate the feasibility of HCl-treated zero-valent iron (Fe(0)) combined with different adsorbents as hybrid systems for simultaneous removal of nitrate (NO(3)(-)) and ammonium (NH(4)(+)) ions from aqueous solution. The maximum NO(3)(-) removal in combined Fe(0)-granular activated carbon (GAC), Fe(0)-filtralite and Fe(0)-sepiolite systems was 86, 96 and 99%, respectively, at 45 °C for 24 h reaction time. The NO(3)(-) removal rate increased with the increase in initial NO(3)(-) concentration. The NO(3)(-) removal efficiency by hybrid systems was in the order of sepiolite > filtralite > GAC. The NH(4)(+) produced during the denitrification process by Fe(0) was successfully removed by the adsorbents, with the removal efficiency in the order of GAC > sepiolite > filtralite. Results of the present study suggest that the use of a hybrid system could be a promising technology for achieving simultaneous removal of NO(3)(-) and NH(4)(+) ions from aqueous solution.

  13. Including Life Cycle Assessment for decision-making in controlling wastewater nutrient removal systems.

    PubMed

    Corominas, Lluís; Larsen, Henrik F; Flores-Alsina, Xavier; Vanrolleghem, Peter A

    2013-10-15

    This paper focuses on the use of Life Cycle Assessment (LCA) to evaluate the performance of seventeen control strategies in wastewater treatment plants (WWTPs). It tackles the importance of using site-specific factors for nutrient enrichment when decision-makers have to select best operating strategies. Therefore, the LCA evaluation is repeated for three different scenarios depending on the limitation of nitrogen (N), phosphorus (P), or both, when evaluating the nutrient enrichment impact in water bodies. The LCA results indicate that for treated effluent discharged into N-deficient aquatic systems (e.g. open coastal areas) the most eco-friendly strategies differ from the ones dealing with discharging into P-deficient (e.g. lakes and rivers) and N&P-deficient systems (e.g. coastal zones). More particularly, the results suggest that strategies that promote increased nutrient removal and/or energy savings present an environmental benefit for N&P and P-deficient systems. This is not the case when addressing N-deficient systems for which the use of chemicals (even for improving N removal efficiencies) is not always beneficial for the environment. A sensitivity analysis on using weighting of the impact categories is conducted to assess how value choices (policy decisions) may affect the management of WWTPs. For the scenarios with only N-limitation, the LCA-based ranking of the control strategies is sensitive to the choice of weighting factors, whereas this is not the case for N&P or P-deficient aquatic systems.

  14. Adsorptive removal of naphthalene induced by structurally different Gemini surfactants in a soil-water system.

    PubMed

    Wei, Jia; Li, Jun; Huang, Guohe; Wang, Xiujie; Chen, Guanghui; Zhao, Baihang

    2016-09-01

    A new generation of surfactant, Gemini surfactants, have been synthesized and have attracted the attention of various industrial and academic research groups. This study focused on the use of symmetric and dissymmetric quaternary ammonium Gemini surfactants to immobilize naphthalene onto soil particles, and is used as an example of an innovative application to remove HOC in situ using the surfactant-enhanced sorption zone. The sorption capacity of modified soils by Gemini surfactant and natural soils was compared and the naphthalene sorption efficiency, in the absence and presence of Gemini surfactants with different alkyl chain lengths, was investigated in the soil-water system. The results have shown that the increased added Gemini surfactant formed admicelles at the interface of soil/water having superior capability to retard contaminant. Symmetric and dissymmetric Gemini surfactants have opposite effect on the aspect of removing of PAH attributing to their solubilization and sorption behavior in soil-water system. Compared with the natural soil, sorption of naphthalene by Gemini-modified soil is noticeably enhanced following the order of C12-2-16 < C12-2-12 < C12-2-8. However, the symmetric Gemini surfactant C12-2-12 is the optimized one for in situ barrier remediation, which is not only has relative high retention ability but also low dosage.

  15. Biological removal of the xenobiotic trichloroethylene (TCE) through cometabolism in nitrifying systems.

    PubMed

    Kocamemi, B Alpaslan; Ceçen, F

    2010-01-01

    In the present study, cometabolic TCE degradation was evaluated using NH(4)-N as the growth-substrate. At initial TCE concentrations up to 845 microg/L, TCE degradation followed first-order kinetics. The increase in ammonium utilization rate favored the degradation of TCE. This ensured that biological transformation of TCE in nitrifying systems is accomplished through a cometabolic pathway by the catalysis of non-specific ammonia oxygenase enzyme of nitrifiers. The transformation yield (T(y)) of TCE, the amount of TCE degraded per unit mass of NH(4)-N, strongly depended on the initial NH(4)-N and TCE concentrations. In order to allow a rough estimation of TCE removal and nitrification at different influent TCE and NH(4)-N concentrations, a linear relationship was developed between 1/T(y) and the initial NH(4)-N/TCE ratio. The estimated T(y) values lead to the conclusion that nitrifying systems are promising candidates for biological removal of TCE through cometabolism.

  16. Calcium effect on the metabolic pathway of phosphorus accumulating organisms in enhanced biological phosphorus removal systems.

    PubMed

    Zhang, Hai-Ling; Sheng, Guo-Ping; Fang, Wei; Wang, Yong-Peng; Fang, Cai-Yun; Shao, Li-Min; Yu, Han-Qing

    2015-11-01

    Phosphorus accumulating organisms (PAOs) have been found to act as glycogen-accumulating organisms (GAOs) under certain conditions, thus, the deterioration in the performance of enhanced biological phosphorus removal systems is not always attributed to the proliferation of GAOs. In this work, the effects of calcium on the metabolic pathway of PAOs were explored. It was found that when the influent Ca(2+) concentration was elevated, the tendency and extent of extracellular calcium phosphate precipitation increased, and the intracellular inert Ca-bound polyphosphate was synthesized, while the microbial population remained almost unchanged. The changes in the ratios of phosphorus released/acetate uptaken, the glycogen degraded/acetate uptaken and the poly-β-hydroxyalkanoates synthesized/acetate uptaken during the anaerobic period confirm that, as the influent Ca(2+) concentration was increased, the polyphosphate-accumulating metabolism was partially shifted to the glycogen-accumulating metabolism. At an influent Ca(2+) around 50 mg/L, in addition to the extracellular calcium phosphate precipitation, the intracellular inert Ca-bound polyphosphate synthesis might also be involved in the metabolic change of PAOs. The results of the present work would be beneficial to better understand the biochemical metabolism of PAOs in enhanced biological phosphorus removal systems.

  17. Centrifugal accelerator, system and method for removing unwanted layers from a surface

    DOEpatents

    Foster, Christopher A.; Fisher, Paul W.

    1995-01-01

    A cryoblasting process having a centrifugal accelerator for accelerating frozen pellets of argon or carbon dioxide toward a target area utilizes an accelerator throw wheel designed to induce, during operation, the creation of a low-friction gas bearing within internal passages of the wheel which would otherwise retard acceleration of the pellets as they move through the passages. An associated system and method for removing paint from a surface with cryoblasting techniques involves the treating, such as a preheating, of the painted surface to soften the paint prior to the impacting of frozen pellets thereagainst to increase the rate of paint removal. A system and method for producing large quantities of frozen pellets from a liquid material, such as liquid argon or carbon dioxide, for use in a cryoblasting process utilizes a chamber into which the liquid material is introduced in the form of a jet which disintegrates into droplets. A non-condensible gas, such as inert helium or air, is injected into the chamber at a controlled rate so that the droplets freeze into bodies of relatively high density.

  18. Affinity maturation of antibodies requires integrity of the adult thymus.

    PubMed

    AbuAttieh, Mouhammed; Bender, Diane; Liu, Esther; Wettstein, Peter; Platt, Jeffrey L; Cascalho, Marilia

    2012-02-01

    The generation of B-cell responses to proteins requires a functional thymus to produce CD4(+) T cells which helps in the activation and differentiation of B cells. Because the mature T-cell repertoire has abundant cells with the helper phenotype, one might predict that in mature individuals, the generation of B-cell memory would proceed independently of the thymus. Contrary to that prediction, we show here that the removal of the thymus after the establishment of the T-cell compartment or sham surgery without removal of the thymus impairs the affinity maturation of antibodies. Because removal or manipulation of the thymus did not decrease the frequency of mutation of the Ig variable heavy chain exons encoding antigen-specific antibodies, we conclude that the thymus controls affinity maturation of antibodies in the mature individual by facilitating the selection of B cells with high-affinity antibodies.

  19. A Pilot-scale Benthic Microbial Electrochemical System (BMES) for Enhanced Organic Removal in Sediment Restoration

    NASA Astrophysics Data System (ADS)

    Li, Henan; Tian, Yan; Qu, Youpeng; Qiu, Ye; Liu, Jia; Feng, Yujie

    2017-01-01

    A benthic microbial electrochemical systems (BMES) of 195 L (120 cm long, 25 cm wide and 65 cm height) was constructed for sediment organic removal. Sediment from a natural river (Ashi River) was used as test sediments in the present research. Three-dimensional anode (Tri-DSA) with honeycomb structure composed of carbon cloth and supporting skeleton was employed in this research for the first time. The results demonstrated that BMES performed good in organic-matter degradation and energy generation from sediment and could be considered for river sediments in situ restoration as novel method. Community analysis from the soil and anode using 16S rDNA gene sequencing showed that more electrogenic functional bacteria was accumulated in anode area when circuit connected than control system.

  20. A Pilot-scale Benthic Microbial Electrochemical System (BMES) for Enhanced Organic Removal in Sediment Restoration

    PubMed Central

    Li, Henan; Tian, Yan; Qu, Youpeng; Qiu, Ye; Liu, Jia; Feng, Yujie

    2017-01-01

    A benthic microbial electrochemical systems (BMES) of 195 L (120 cm long, 25 cm wide and 65 cm height) was constructed for sediment organic removal. Sediment from a natural river (Ashi River) was used as test sediments in the present research. Three-dimensional anode (Tri-DSA) with honeycomb structure composed of carbon cloth and supporting skeleton was employed in this research for the first time. The results demonstrated that BMES performed good in organic-matter degradation and energy generation from sediment and could be considered for river sediments in situ restoration as novel method. Community analysis from the soil and anode using 16S rDNA gene sequencing showed that more electrogenic functional bacteria was accumulated in anode area when circuit connected than control system. PMID:28059105

  1. Fate and effect of benzalkonium chlorides in a continuous-flow biological nitrogen removal system treating poultry processing wastewater.

    PubMed

    Hajaya, Malek G; Pavlostathis, Spyros G

    2012-08-01

    Quaternary ammonium compounds (QACs) are used for sanitation in many poultry processing facilities. This work investigated the fate and effect of a mixture of benzalkonium chlorides (BACs), a class of QACs widely used in commercial antimicrobial formulations, on the biological nitrogen removal (BNR) processes. A laboratory-scale BNR system was operated continuously for 670 days, fed with poultry processing wastewater amended with a mixture of BACs. Initially, the nitrogen removal efficiency deteriorated at a BAC feed concentration of 5 mg/L due to the complete inhibition of nitrification. However, after 27 days of operation, the system recovered and achieved 100% ammonia removal. High nitrogen removal efficiency was achieved even after the feed BAC concentration was stepwise increased up to 120 mg/L. Batch nitrification assays performed before, during, and after BAC exposure, showed that rapid microbial acclimation and BAC biodegradation contributed to the recovery of nitrification achieving efficient and stable long-term BNR system operation.

  2. Effect of collagen removal on shear bond strength of two single-bottle adhesive systems.

    PubMed

    Saboia, V P; Rodrigues, A L; Pimenta, L A

    2000-01-01

    This study evaluated the effect of collagen removal on the shear bond strength for two single-bottle adhesive systems. The ultrastructure of the dentin after treatments and the dentin-resin interface were examined under SEM. The buccal and lingual surfaces of 80 extracted human third molars were ground to expose dentin. Teeth were randomly assigned to four groups and received the following treatments: Group 1(P&B 2.1), Prime & Bond 2.1 adhesive was applied according to the manufacturer's directions and Restorative Z100 composite resin was bonded to the dentin surface; Group 2 (P&B 2.1/NaOCl), the same procedures were followed as for Group 1 except that the surfaces were treated with 10% sodium hypochlorite (NaOCl) for one minute after acid conditioning; Group 3 (SB), Single Bond (3M) was applied according to the manufacturer's recommendations; Group 4 (SB/NaOCl), the same procedure was followed for Group 2, using Single Bond. The specimens were stored in humidity at 37 degrees C for 24 hours and tested in a shear mode at a crosshead speed of 0.5 mm/minute. The Kruskal-Wallis test and Multiple Comparisons were used for statistical analysis of the data. A one-minute exposure of dentin to 10% NaOCl following acid conditioning resulted in a significant increase of the dentin shear bond strength for Prime & Bond 2.1. The same treatment for Single Bond resulted in a significant reduction in bond strength. Groups 1 and 3 were not statistically different from each other. The presence of a collagen layer resulted in the formation of a hybrid layer and similar values of adhesion for both adhesive systems. The results may suggest that collagen removal improves the bond strength for this acetone-based adhesive system but several such systems would need to be investigated.

  3. Rapid Cycling CO2 and H2O Removal System for EMU

    NASA Technical Reports Server (NTRS)

    Alptekin, Gokhan; Cates, Matthew; Dubovik, Margarita; Gershanovich, Yevgenia; Paul, Heather; Thomas, Gretchen

    2006-01-01

    NASA's planned future missions set stringent demands on the design of the Portable Life Support Systems (PLSS), requiring dramatic reductions in weight, decreased reliance on supplies and greater flexibility on the types of missions. Use of regenerable systems that reduce weight and volume of the EMU is of critical importance to NASA, both for low orbit operations and for long duration manned missions. The CO2 and humidity control unit in the existing PLSS design is relatively large, since it has to remove 8 hours worth of CO2. If the sorbent regeneration can be carried out during the extravehicular activity (EVA) with a relatively high regeneration frequency, the size of the sorbent canister and weight can be significantly reduced. TDA Research, Inc. (TDA) is developing a compact, regenerable sorbent-based system to control CO2 and humidity in the space suit ventilation loop. The sorbent can be regenerated using space vacuum during the EVA, eliminating all duration-limiting elements in the life support system. This paper summarizes the results of the sorbent development and testing, and evaluation efforts. The results of a preliminary system analysis are also included, showing the size and volume reductions provided by the new system.

  4. Removal of phenol in a constructed wetland system and the relative contribution of plant roots, microbial activity and porous bed.

    PubMed

    Kurzbaum, E; Zimmels, Y; Kirzhner, F; Armon, R

    2010-01-01

    Analysis of a low organic load constructed wetland (CW) system was performed in order to understand the relative role of its various components contribution in phenol removal (100 mg/L) under controlled plant biomass/gravel/water experimental ratios (50 g/450 g/100 mL). The results [expressed as phenol50/time (hours) required to remove 50% of the initial phenol concentration] showed that the highest phenol removal occurred by combined biofilms from roots and gravel attached (phenol50=19), followed by gravel biofilm (phenol50=105) and planktonic (suspended in water) bacteria (phenol50=>200). An in depth analysis revealed that plants contribution alone (antibiotics sterilized) was minor (phenol50=>89) while roots supported biofilm resulted in a significant phenol removal (phenol50=15). Therefore in this type of CW, the main phenol removal active fraction could be attributed to plant roots' biofilm bacteria.

  5. Metal oxide absorbents for regenerative carbon dioxide and water vapor removal for advanced portable life support systems

    NASA Technical Reports Server (NTRS)

    Hart, Joan M.; Borghese, Joseph B.; Chang, Craig H.; Stonesifer, Greg T.

    1991-01-01

    Recent studies of Allied Signal metal oxide based absorbents demonstrated that these absorbents offer a unique capability to regeneratively remove both metabolic carbon dioxide and water vapor from breathing air; previously, metal oxides were considered only for the removal of CO2. The concurrent removal of CO2 and H2O vapor can simplify the astronaut Portable Life Support System (PLSS) by combining the CO2 and humidity control functions into one regenerative component. The use of metal oxide absorbents for removal of both CO2 ad H2O vapor in the PLSS is the focus of an ongoing program. The full scale Metal Oxide Carbon dioxide and Humidity Remover (MOCHR) and regeneration unit is described.

  6. Simultaneous removal of COD and ammonium from landfill leachate using an anaerobic-aerobic moving-bed biofilm reactor system.

    PubMed

    Chen, Sheng; Sun, Dezhi; Chung, Jong-Shik

    2008-01-01

    The performance of a moving-bed biofilm reactor (MBBR) system with an anaerobic-aerobic arrangement was investigated to treat landfill leachate for simultaneous removal of COD and ammonium. It was found that the anaerobic MBBR played a major role in COD removal due to methanogenesis, and the aerobic MBBR acted as COD-polishing and ammonium removal step. The contribution of the anaerobic MBBR to total COD removal efficiency reached 91% at an organic loading rate (OLR) of 4.08 kgCOD/(m3d), and gradually decreased to 86% when feed OLR was increased to 15.70 kgCOD/(m3d). Because of the complementary function of the aerobic reactor, the total COD removal efficiency of the system had a slight decrease from 94% to 92% even though the feed OLR was increased from 4.08 to 15.70 kgCOD/(m3d). Hydraulic retention time (HRT) had a significant effect on NH+4-N removal; more than 97% of the total NH+4-N removal efficiency could be achieved when the HRT of the aerobic MBBR was more than 1.25 days. The anaerobic-aerobic system had a strong tolerance to shock loading. A decrease in COD removal efficiency of only 7% was observed when the OLR was increased by four times and shock duration was 24 h, and the system could recover the original removal efficiency in 3 days. The average sludge yield of the anaerobic reactor was estimated to be 0.0538 gVSS/gCOD rem.

  7. A high loading overland flow system: Impacts on soil characteristics, grass constituents, yields and nutrient removal.

    PubMed

    Wen, C G; Chen, T H; Hsu, F H; Lu, C H; Lin, J B; Chang, C H; Chang, S P; Lee, C S

    2007-04-01

    The objectives of this paper are to determine effects of different grass species and their harvests on pollutant removal, elucidate impacts on soil characteristics and grass constituents, observe grass yield and quantify nutrient uptake by vegetation in an overland flow system (OLFS). Polluted creek water was applied to eight channels in the OLFS, which were planted with Paragrass, Nilegrass, Cattail, and Vetiver, with each two channels being randomly planted with a given grass species. The grass in one channel was harvested while that in the other channel was not. At a high rate of 27.8 m d(-1) hydraulic loading, the removal efficiencies of conventional pollutants such as BOD, COD, suspended solids (SS), and total coliforms in wastewater are not affected by the type of the grasses species, but those of nitrogen and phosphorus are affected by different species. Overall average removal efficiencies of BOD, COD, SS, ammonia, total nitrogen, total phosphorus and total coliforms through the OLFS are 42%, 48%, 78%, 47%, 40%, 33% and 89%, respectively. The concentration of nitrate, however, increases due to nitrification. Soil characteristics in OLFS have been changed significantly; specific conductivity, organic matter, exchangeable magnesium, extractable copper and zinc in soils all increase with time while pHs decrease. During the winter season, there is a significant accumulation of nitrate in grass with the subsequent reduction during the active growing season (Spring). The contents of nitrate and phosphorus in grass tissue are higher than those of grass in general pastureland, probably due to nutrient luxury uptake by grass. The overall grass yield, growth rate and nutrient uptake are quantified and implication of such high rate OLFS discussed.

  8. An artificially constructed Syngonium podophyllum-Aspergillus niger combinate system for removal of uranium from wastewater.

    PubMed

    He, Jia-dong; Wang, Yong-dong; Hu, Nan; Ding, Dexin; Sun, Jing; Deng, Qin-wen; Li, Chang-wu; Xu, Fei

    2015-12-01

    Aspergillus niger was inoculated to the roots of five plants, and the Syngonium podophyllum-A. niger combinate system (SPANCS) was found to be the most effective in removing uranium from hydroponic liquid with initial uranium concentration of 5 mg L(-1). Furthermore, the hydroponic experiments on the removal of uranium from the hydroponic liquids with initial uranium concentrations of 0.5, 1.0, and 3.0 mg L(-1) by the SPANCS were conducted, the inhibitory effect of A. niger on the growth of S. podophyllum in the SPANCS was studied, the accumulation characteristics of uranium by S. podophyllum in the SPANCS were analyzed, and the Fourier transform infrared (FT-IR) and extended X-ray absorption fine structure (EXAFS) spectra were measured. The results show that the removal of uranium by the SPANCS from the hydroponic liquids with initial uranium concentrations of 0.5, 1.0, and 3.0 mg L(-1) reached 98.20, 97.90, and 98.50%, respectively, after 37 days of accumulation of uranium; that the uranium concentrations in the hydroponic liquids decreased to 0.009, 0.021, and 0.045 mg L(-1), respectively, which are lower than the stipulated concentration for discharge of 0.050 mg L(-1) by the People's Republic of China; that A. niger helped to generate more groups in the root of S. podophyllum which can improve the complexing capability of S. podophyllum for uranium; and that the uranium accumulated in the root of S. podophyllum was in the form of phosphate uranyl and carboxylic uranyl.

  9. Applications of porous electrodes to metal-ion removal and the design of battery systems

    SciTech Connect

    Trost, G.G.

    1983-09-01

    This dissertation treats the use of porous electrodes as electrochemical reactors for the removal of dilute metal ions. A methodology for the scale-up of porous electrodes used in battery applications is given. Removal of 4 ..mu..g Pb/cc in 1 M sulfuric acid was investigated in atmospheric and high-pressure, flow-through porous reactors. The atmospheric reactor used a reticulated vitreous carbon porous bed coated in situ with a mercury film. Best results show 98% removal of lead from the feed stream. Results are summarized in a dimensionless plot of Sherwood number vs Peclet number. High-pressure, porous-electrode experiments were performed to investigate the effect of pressure on the current efficiency. Pressures were varied up to 120 bar on electrode beds of copper or lead-coated spheres. The copper spheres showed high hydrogen evolution rates which inhibited lead deposition, even at high cathodic overpotentials. Use of lead spheres inhibited hydrogen evolution but often resulted in the formation of lead sulfate layers; these layers were difficult to reduce back to lead. Experimental data of one-dimensional porous battery electrodes are combined with a model for the current collector and cell connectors to predict ultimate specific energy and maximum specific power for complete battery systems. Discharge behavior of the plate as a whole is first presented as a function of depth of discharge. These results are combined with the voltage and weight penalties of the interconnecting bus and post, positive and negative active material, cell container, etc. to give specific results for the lithium-aluminum/iron sulfide high-temperature battery. Subject to variation is the number of positive electrodes, grid conductivity, minimum current-collector weight, and total delivered capacity. The battery can be optimized for maximum energy or power, or a compromise design may be selected.

  10. Enhanced removal of petroleum hydrocarbons using a bioelectrochemical remediation system with pre-cultured anodes.

    PubMed

    Venkidusamy, Krishnaveni; Megharaj, Mallavarapu; Marzorati, Massimo; Lockington, Robin; Naidu, Ravi

    2016-01-01

    Bioelectrochemical remediation (BER) systems such as microbial fuel cells (MFCs) have recently emerged as a green technology for the effective remediation of petroleum hydrocarbon contaminants (PH) coupled with simultaneous energy recovery. Recent research has shown that biofilms previously enriched for substrate degrading bacteria resulted in excellent performance in terms of substrate removal and electricity generation but the effects on hydrocarbon contaminant degradation were not examined. Here we investigate the differences between enriched biofilm anodes and freshly inoculated new anodes in diesel fed single chamber mediatorless microbial fuel cells (DMFC) using various techniques for the enhancement of PH contaminant remediation with concomitant electricity generation. An anodophilic microbial consortium previously selected for over a year through continuous culturing with a diesel concentration of about 800mgl(-1) and which now showed complete removal of this concentration of diesel within 30days was compared to that of a freshly inoculated new anode MFC (showing 83.4% removal of diesel) with a simultaneous power generation of 90.81mW/m(2) and 15.04mW/m(2) respectively. The behaviour of pre-cultured anodes at a higher concentration of PH (8000mgl(-1)) was also investigated. Scanning electron microscopy observation revealed a thick biofilm covering the pre-cultured anodic electrode but not the anode from the freshly inoculated MFC. High resolution imaging showed the presence of thin 60nm diametre pilus-like projections emanating from the cells. Anodic microbial community profiling confirmed that the selection for diesel degrading exoelectrogenic bacteria had occurred. Identification of a biodegradative gene (alkB) provided strong evidence of the catabolic pathway used for diesel degradation in the DMFCs.

  11. One-step affinity tag purification of full-length recombinant human AP-1 complexes from bacterial inclusion bodies using a polycistronic expression system.

    PubMed

    Wang, Wei-Ming; Lee, A-Young; Chiang, Cheng-Ming

    2008-05-01

    The AP-1 transcription factor is a dimeric protein complex formed primarily between Jun (c-Jun, JunB, JunD) and Fos (c-Fos, FosB, Fra-1, Fra-2) family members. These distinct AP-1 complexes are expressed in many cell types and modulate target gene expression implicated in cell proliferation, differentiation, and stress responses. Although the importance of AP-1 has long been recognized, the biochemical characterization of AP-1 remains limited in part due to the difficulty in purifying full-length, reconstituted dimers with active DNA-binding and transcriptional activity. Using a combination of bacterial coexpression and epitope-tagging methods, we successfully purified all 12 heterodimers (3 Junx4 Fos) of full-length human AP-1 complexes as well as c-Jun/c-Jun, JunD/JunD, and c-Jun/JunD dimers from bacterial inclusion bodies using one-step nickel-NTA affinity tag purification following denaturation and renaturation of coexpressed AP-1 subunits. Coexpression of two constitutive components in a dimeric AP-1 complex helps stabilize the proteins when compared with individual protein expression in bacteria. Purified dimeric AP-1 complexes are functional in sequence-specific DNA binding, as illustrated by electrophoretic mobility shift assays and DNase I footprinting, and are also active in transcription with in vitro-reconstituted human papillomavirus (HPV) chromatin containing AP-1-binding sites in the native configuration of HPV nucleosomes. The availability of these recombinant full-length human AP-1 complexes has greatly facilitated mechanistic studies of AP-1-regulated gene transcription in many biological systems.

  12. Time-Resolved Investigation of Molecular Components Involved in the Induction of [Formula: see text] High Affinity Transport System in Maize Roots.

    PubMed

    Pii, Youry; Alessandrini, Massimiliano; Dall'Osto, Luca; Guardini, Katia; Prinsi, Bhakti; Espen, Luca; Zamboni, Anita; Varanini, Zeno

    2016-01-01

    The induction, i.e., the rapid increase of nitrate ([Formula: see text]) uptake following the exposure of roots to the anion, was studied integrating physiological and molecular levels in maize roots. Responses to [Formula: see text] treatment were characterized in terms of changes in [Formula: see text] uptake rate and plasma membrane (PM) H(+)-ATPase activity and related to transcriptional and protein profiles of NRT2, NRT3, and PM H(+)-ATPase gene families. The behavior of transcripts and proteins of ZmNRT2s and ZmNRT3s suggested that the regulation of the activity of inducible high-affinity transport system (iHATS) is mainly based on the transcriptional/translational modulation of the accessory protein ZmNRT3.1A. Furthermore, ZmNRT2.1 and ZmNRT3.1A appear to be associated in a ∼150 kDa oligomer. The expression trend during the induction of the 11 identified PM H(+)-ATPase transcripts indicates that those mainly involved in the response to [Formula: see text] treatment are ZmHA2 and ZmHA4. Yet, partial correlation between the gene expression, protein levels and enzyme activity suggests an involvement of post-transcriptional and post-translational mechanisms of regulation. A non-denaturing Deriphat-PAGE approach allowed demonstrating for the first time that PM H(+)-ATPase can occur in vivo as hexameric complex together with the already described monomeric and dimeric forms.

  13. Time-Resolved Investigation of Molecular Components Involved in the Induction of NO3– High Affinity Transport System in Maize Roots

    PubMed Central

    Pii, Youry; Alessandrini, Massimiliano; Dall’Osto, Luca; Guardini, Katia; Prinsi, Bhakti; Espen, Luca; Zamboni, Anita; Varanini, Zeno

    2016-01-01

    The induction, i.e., the rapid increase of nitrate (NO3–) uptake following the exposure of roots to the anion, was studied integrating physiological and molecular levels in maize roots. Responses to NO3– treatment were characterized in terms of changes in NO3– uptake rate and plasma membrane (PM) H+-ATPase activity and related to transcriptional and protein profiles of NRT2, NRT3, and PM H+-ATPase gene families. The behavior of transcripts and proteins of ZmNRT2s and ZmNRT3s suggested that the regulation of the activity of inducible high-affinity transport system (iHATS) is mainly based on the transcriptional/translational modulation of the accessory protein ZmNRT3.1A. Furthermore, ZmNRT2.1 and ZmNRT3.1A appear to be associated in a ∼150 kDa oligomer. The expression trend during the induction of the 11 identified PM H+-ATPase transcripts indicates that those mainly involved in the response to NO3– treatment are ZmHA2 and ZmHA4. Yet, partial correlation between the gene expression, protein levels and enzyme activity suggests an involvement of post-transcriptional and post-translational mechanisms of regulation. A non-denaturing Deriphat-PAGE approach allowed demonstrating for the first time that PM H+-ATPase can occur in vivo as hexameric complex together with the already described monomeric and dimeric forms. PMID:27877183

  14. In Vivo Analysis of HPr Reveals a Fructose-Specific Phosphotransferase System That Confers High-Affinity Uptake in Streptomyces coelicolor

    PubMed Central

    Nothaft, Harald; Parche, Stephan; Kamionka, Annette; Titgemeyer, Fritz

    2003-01-01

    HPr, the histidine-containing phosphocarrier protein of the bacterial phosphotransferase system (PTS), serves multiple functions in carbohydrate uptake and carbon source regulation in low-G+C-content gram-positive bacteria and in gram-negative bacteria. To assess the role of HPr in the high-G+C-content gram-positive organism Streptomyces coelicolor, the encoding gene, ptsH, was deleted. The ptsH mutant BAP1 was impaired in fructose utilization, while growth on other carbon sources was not affected. Uptake assays revealed that BAP1 could not transport appreciable amounts of fructose, while the wild type showed inducible high-affinity fructose transport with an apparent Km of 2 μM. Complementation and reconstitution experiments demonstrated that HPr is indispensable for a fructose-specific PTS activity. Investigation of the putative fruKA gene locus led to identification of the fructose-specific enzyme II permease encoded by the fruA gene. Synthesis of HPr was not specifically enhanced in fructose-grown cells and occurred also in the presence of non-PTS carbon sources. Transcriptional analysis of ptsH revealed two promoters that are carbon source regulated. In contrast to what happens in other bacteria, glucose repression of glycerol kinase was still operative in a ptsH background, which suggests that HPr is not involved in general carbon regulation. However, fructose repression of glycerol kinase was lost in BAP1, indicating that the fructose-PTS is required for transduction of the signal. This study provides the first molecular genetic evidence of a physiological role of the PTS in S. coelicolor. PMID:12533468

  15. PHYSICAL REMOVAL OF MICROBIAL CONTAMINANTS IN DRINKING WATER – WATTS PREMIER INC. WP-4V DRINKING WATER TREATMENT SYSTEM

    EPA Science Inventory

    The Watts Premier WP-4V four-stage POU RO system was tested for removal of bacteria and viruses at NSF’s Drinking Water Treatment Systems Laboratory. Five systems were challenged with the bacteriophage viruses fr and MS2, and the bacteria Brevundimonas diminutaEM. The ...

  16. Design of multiplexed fiber optic chemical sensing system using clad-removable optical fibers

    NASA Astrophysics Data System (ADS)

    Yun, Chang-Yong; Dhital, Dipesh; Lee, Jung-Ryul; Park, Gyuhae; Kwon, Il-Bum

    2012-02-01

    To prevent possible threats to public safety and economic loss from chemical leakage accidents, novel chemical sensing techniques for regular monitoring and leakage detection have been developed for various fields. We propose a fiber optic liquid chemical sensor (FOCS) system using specialty optical fibers and an optical time domain reflectometer (OTDR), and is based on the leaky wave mode sensing principle. OTDR enables simple multiplexing where individual sensor nodes along the fiber length could be interrogated by a common OTDR. The sensor node in the optical fiber is prepared by removing the desired length of a protective layer using mechanical stripping and chemical etching techniques. A novel laser stripping technique with superior capability to fabricate quasi-distributed dense sensor nodes is devised as well. The FOCS system is further analyzed to characterize the sensor response behavior in relation to the sensor node length and possible environmental and chemical temperature effect. Under the condition satisfying the leaky wave mode principle and within the minimum acceptable refractive index (RI) range by the system, this FOCS system could monitor numerous liquid chemicals with variable refractive indices and has been tested with positive results. In addition, the system shows the possibility for multi-point detection and is further expanded into a hybrid technique capable of estimating the refractive index range of the detected chemical.

  17. Selenium removal and mass balance in a constructed flow-through wetland system.

    PubMed

    Gao, S; Tanji, K K; Lin, Z Q; Terry, N; Peters, D W

    2003-01-01

    A field study on the removal of Se from agricultural subsurface drainage was conducted from May 1997 to February 2001 in the Tulare Lake Drainage District (TLDD) of San Joaquin Valley, California. A flow-through wetland system was constructed consisting of ten 15- x 76-m unlined cells that were continuously flooded and planted with either a monotype or combination of plants, including sturdy bulrush [Schoenoplectus robustus (Pursh) M.T. Strong], baltic rush (Juncus balticus Willd.), smooth cordgrass (Spartina alterniflora Loisel.), rabbitsfoot grass [Polypogon monspeliensis (L.) Desf.], salt-grass lDistichlis spicata (L.) Greene], cattail (Typha latifolia L.), tule [Schoenoplectus acutus (Muhl. ex Bigelow) A. Löve & D. Löve], and widgeon grass (Ruppia maritima L.). One cell had no vegetation planted. The objectives of this research were to evaluate Se removal efficiency of each wetland cell and to carry out a mass balance on Se. The inflow drainage water to the cells had average annual Se concentrations of 19 to 22 microg L(-1) dominated by selenate [Se(VI), 95%]. Average weekly water residence time varied from about 3 to 15 d for Cells 1 through 7 (target 7 d), 19 to 33 d for Cells 8 and 9 (target 21 d), and 13 to 18 d for Cell 10 (target 14 d). Average weekly Se concentration ratios of outflow to inflow ranged from 0.45 to 0.79 and mass ratio (concentration x water volume) from 0.24 to 0.52 for year 2000, that is, 21 to 55% reduction in Se concentration and 48 to 76% Se removal in mass by the wetland, respectively. The nonvegetated cell showed the least Se removal both in concentration and in mass. The global mass balance showed that on the average about 59% of the total inflow Se was retained within the cells and Se outputs were outflow (35%), seepage (4%), and volatilization (2%). Independent measurements of the Se retained in the cells totaled 53% of the total Se inflow: 33% in the surface (0-20 cm) sediment, 18% in the organic detrital layer above the

  18. System for continuously and catalytically removing arsenic from shale oil and regenerating the catalyst

    SciTech Connect

    Goyal, S.K.

    1989-04-25

    A system is described for producing and upgrading shale oil, comprising: (a) an oil shale retort for liberating a gaseous effluent stream containing hydrocarbons, residual amounts of arsenic and retort water vapor; (b) means connected to the retort for receiving the effluent stream, and recovering a liquid containing shale oil, arsenic and retort water; (c) separator means connected to the liquid recovery means for receiving the liquid and separating the shale oil arsenic from the retort water; (d) retort water purification means connected to the separator means for receiving and substantially purifying the retort water; (e) a first guard bed containing an arsenic-removing absorber; (f) a second guard bed containing an arsenic-removing absorber; (g) a first means interconnecting the separator means with each of the guard beds and having a first valve means for alternately directing a flow of the shale oil and arsenic through each of the guard beds; (h) a second means interconnecting the retort water purification means with each of the guard beds and having a second value means for alternately directing a flow of the purified retort water through each of the guard beds in opposite phase relationship to the flow of shade oil and arsenic through each of the guard beds.

  19. Removal of nalidixic acid and its degradation products by an integrated MBR-ozonation system.

    PubMed

    Pollice, A; Laera, G; Cassano, D; Diomede, S; Pinto, A; Lopez, A; Mascolo, G

    2012-02-15

    Chemical-biological degradation of a widely spread antibacterial (nalidixic acid) was successfully obtained by an integrated membrane bioreactor (MBR)-ozonation process. The composition of the treated solution simulated the wastewater from the production of the target pharmaceutical, featuring high salinity and a relevant concentration of sodium acetate. Aim of treatment integration was to exploit the synergistic effects of chemical oxidation and bioprocesses, by adopting the latter to remove most of the COD and the ozonation biodegradable products. Integration was achieved by placing ozonation in the recirculation stream of the bioreactor effluent. The recirculation flow rate was three-fold the MBR feed, and the performance of the integrated system was compared to the standard polishing configuration (single ozonation step after the MBR). Results showed that the introduction of the ozonation step did not cause relevant drawbacks to both biological and filtration processes. nalidixic acid passed undegraded through the MBR and was completely removed in the ozonation step. Complete degradation of most of the detected ozonation products was better achieved with the integrated MBR-ozonation process than using the sequential treatment configuration, i.e. ozone polishing after MBR, given the same ozone dosage.

  20. [Nitrate removal from recirculating aquaculture system using polyhydroxybutyrate-co-hydroxyvalerate as carbon source ].

    PubMed

    Zhang, Lanhe; Liu, Lili; Qiu, Tianlei; Gao, Min; Han, Meilin; Yuan, Ding; Wang, Xuming

    2014-09-04

    [ OBJECTIVE] Polyhydroxybutyrate-co-hydroxyvalerate (PHBV) was used as solid carbon source and biofilm carrier to remove nitrate from recirculating aquaculture system (RAS). Dynamics of microbial community structure in biofilm coating on carbon source packed into denitrification reactor were investigated. [METHODS] Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was used to analyze the microbial community in biofilm from denitrifiation reactor. Bacteria degrading PHBV were isolated from the reactor using pure culture method. [RESULTS] Nitrate decreased remarkably in the RAS connected with dentrification reactor. In contrast, Nitrate increased continuously in the conventional RAS without dentrification reactor. According to the phylogenetic analysis, the microbes in the biofilm samples from denitrification reactor were divided into Proteobacteria ( p-proteobacteria, γ-proteobacteria and δ- proteobacteria) , Firmicutes and Bacteroidetes. The major advantageous populations were Acidovorax and Bacillus in the 40-day reactor. The advantageous populations in the 150-day reactor were in order of Clostridium, Desulfitobacterium, Dechloromonas, Pseudoxanthomonas and Flavobacterium. Pure cultures of bacteria degrading PHBV isolated from denitrification reactor were classified into Acidovorax, Methylibium, Pseudoxanthomonas and Dechloromonas. [CONCLUSION] Nitrate could be removed effectively from RAS using PHBV as carbon source. Advantageous bacteria and their dynamic changes were ascertained in biofilm from denitrification reactor packed with PHBV.

  1. Electrical Stimulation Improves Microbial Salinity Resistance and Organofluorine Removal in Bioelectrochemical Systems

    PubMed Central

    Feng, Huajun; Zhang, Xueqin; Guo, Kun; Vaiopoulou, Eleni; Shen, Dongsheng; Long, Yuyang; Yin, Jun

    2015-01-01

    Fed batch bioelectrochemical systems (BESs) based on electrical stimulation were used to treat p-fluoronitrobenzene (p-FNB) wastewater at high salinities. At a NaCl concentration of 40 g/liter, p-FNB was removed 100% in 96 h in the BES, whereas in the biotic control (BC) (absence of current), p-FNB removal was only 10%. By increasing NaCl concentrations from 0 g/liter to 40 g/liter, defluorination efficiency decreased around 40% in the BES, and in the BC it was completely ceased. p-FNB was mineralized by 30% in the BES and hardly in the BC. Microorganisms were able to store 3.8 and 0.7 times more K+ and Na+ intracellularly in the BES than in the BC. Following the same trend, the ratio of protein to soluble polysaccharide increased from 3.1 to 7.8 as the NaCl increased from 0 to 40 g/liter. Both trends raise speculation that an electrical stimulation drives microbial preference toward K+ and protein accumulation to tolerate salinity. These findings are in accordance with an enrichment of halophilic organisms in the BES. Halobacterium dominated in the BES by 56.8% at a NaCl concentration of 40 g/liter, while its abundance was found as low as 17.5% in the BC. These findings propose a new method of electrical stimulation to improve microbial salinity resistance. PMID:25819966

  2. System dynamics modeling of nitrogen removal in a stormwater infiltration basin with biosorption-activated media.

    PubMed

    Xuan, Zhemin; Chang, Ni-Bin; Wanielista, Martin P; Williams, Evan Shane

    2013-07-01

    Stormwater infiltration basins, one of the typical stormwater best management practices, are commonly constructed for surface water pollution control, flood mitigation, and groundwater restoration in rural or residential areas. These basins have soils with better infiltration capacity than the native soil; however, the ever-increasing contribution of nutrients to groundwater from stormwater due to urban expansion makes existing infiltration basins unable to meet groundwater quality criteria related to environmental sustainability and public health. This issue requires retrofitting current infiltration basins for flood control as well as nutrient control before the stormwater enters the groundwater. An existing stormwater infiltration basin in north-central Florida was selected, retrofitted, and monitored to identify subsurface physiochemical and biological processes during 2007-2010 to investigate nutrient control processes. This implementation in the nexus of contaminant hydrology and ecological engineering adopted amended soil layers packed with biosorption activated media (BAM; tire crumb, silt, clay, and sand) to perform nutrient removal in a partitioned forebay using a berm. This study presents an infiltration basin-nitrogen removal (IBNR) model, a system dynamics model that simulates nitrogen cycling in this BAM-based stormwater infiltration basin with respect to changing hydrologic conditions and varying dissolved nitrogen concentrations. Modeling outputs of IBNR indicate that denitrification is the biogeochemical indicator in the BAM layer that accounted for a loss of about one third of the total dissolved nitrogen mass input.

  3. Simulation of integrated pollutant removal (IPR) water-treatment system using ASPEN Plus

    SciTech Connect

    Harendra, Sivaram; Oryshcyhn, Danylo [U.S. DOE Ochs, Thomas [U.S. DOE Gerdemann, Stephen; Clark, John

    2013-01-01

    Capturing CO2 from fossil fuel combustion provides an opportunity for tapping a significant water source which can be used as service water for a capture-ready power plant and its peripherals. Researchers at the National Energy Technology Laboratory (NETL) have patented a process—Integrated Pollutant Removal (IPR®)—that uses off-the-shelf technology to produce a sequestration ready CO2 stream from an oxy-combustion power plant. Water condensed from oxy-combustion flue gas via the IPR system has been analyzed for composition and an approach for its treatment—for in-process reuse and for release—has been outlined. A computer simulation model in ASPEN Plus has been developed to simulate water treatment of flue gas derived wastewater from IPR systems. At the field installation, water condensed in the IPR process contains fly ash particles, sodium (largely from spray-tower buffering) and sulfur species as well as heavy metals, cations, and anions. An IPR wastewater treatment system was modeled using unit operations such as equalization, coagulation and flocculation, reverse osmosis, lime softening, crystallization, and pH correction. According to the model results, 70% (by mass) of the inlet stream can be treated as pure water, the other 20% yields as saleable products such as gypsum (CaSO4) and salt (NaCl) and the remaining portion is the waste. More than 99% of fly ash particles are removed in the coagulation and flocculation unit and these solids can be used as filler materials in various applications with further treatment. Results discussed relate to a slipstream IPR installation and are verified experimentally in the coagulation/flocculation step.

  4. Mechanistic characterization of the thioredoxin system in the removal of hydrogen peroxide.

    PubMed

    Pannala, Venkat R; Dash, Ranjan K

    2015-01-01

    The thioredoxin system, which consists of a family of proteins, including thioredoxin (Trx), peroxiredoxin (Prx), and thioredoxin reductase (TrxR), plays a critical role in the defense against oxidative stress by removing harmful hydrogen peroxide (H2O2). Specifically, Trx donates electrons to Prx to remove H2O2 and then TrxR maintains the reduced Trx concentration with NADPH as the cofactor. Despite a great deal of kinetic information gathered on the removal of H2O2 by the Trx system from various sources/species, a mechanistic understanding of the associated enzymes is still not available. We address this issue by developing a thermodynamically consistent mathematical model of the Trx system which entails mechanistic details and provides quantitative insights into the kinetics of the TrxR and Prx enzymes. Consistent with experimental studies, the model analyses of the available data show that both enzymes operate by a ping-pong mechanism. The proposed mechanism for TrxR, which incorporates substrate inhibition by NADPH and intermediate protonation states, well describes the available data and accurately predicts the bell-shaped behavior of the effect of pH on the TrxR activity. Most importantly, the model also predicts the inhibitory effects of the reaction products (NADP(+) and Trx(SH)2) on the TrxR activity for which suitable experimental data are not available. The model analyses of the available data on the kinetics of Prx from mammalian sources reveal that Prx operates at very low H2O2 concentrations compared to their human parasite counterparts. Furthermore, the model is able to predict the dynamic overoxidation of Prx at high H2O2 concentrations, consistent with the available data. The integrated Prx-TrxR model simulations well describe the NADPH and H2O2 degradation dynamics and also show that the coupling of TrxR- and Prx-dependent reduction of H2O2 allowed ultrasensitive changes in the Trx concentration in response to changes in the TrxR concentration at

  5. An Integrated Model for Assessment of Sustainable Agricultural Residue Removal Limits for Bioenergy Systems

    SciTech Connect

    D. Muth; K. M. Bryden

    2003-12-01

    Agricultural residues have been identified as a significant potential resource for bioenergy production, but serious questions remain about the sustainability of harvesting residues. Agricultural residues play an important role in limiting soil erosion from wind and water and in maintaining soil organic carbon. Because of this, multiple factors must be considered when assessing sustainable residue harvest limits. Validated and accepted modeling tools for assessing these impacts include the Revised Universal Soil Loss Equation Version 2 (RUSLE2), the Wind Erosion Prediction System (WEPS), and the Soil Conditioning Index. Currently, these models do not work together as a single integrated model. Rather, use of these models requires manual interaction and data transfer. As a result, it is currently not feasible to use these computational tools to perform detailed sustainable agricultural residue availability assessments across large spatial domains or to consider a broad range of land management practices. This paper presents an integrated modeling strategy that couples existing datasets with the RUSLE2 water erosion, WEPS wind erosion, and Soil Conditioning Index soil carbon modeling tools to create a single integrated residue removal modeling system. This enables the exploration of the detailed sustainable residue harvest scenarios needed to establish sustainable residue availability. Using this computational tool, an assessment study of residue availability for the state of Iowa was performed. This study included all soil types in the state of Iowa, four representative crop rotation schemes, variable crop yields, three tillage management methods, and five residue removal methods. The key conclusions of this study are that under current management practices and crop yields nearly 26.5 million Mg of agricultural residue are sustainably accessible in the state of Iowa, and that through the adoption of no till practices residue removal could sustainably approach 40

  6. Kernel Affine Projection Algorithms

    NASA Astrophysics Data System (ADS)

    Liu, Weifeng; Príncipe, José C.

    2008-12-01

    The combination of the famed kernel trick and affine projection algorithms (APAs) yields powerful nonlinear extensions, named collectively here, KAPA. This paper is a follow-up study of the recently introduced kernel least-mean-square algorithm (KLMS). KAPA inherits the simplicity and online nature of KLMS while reducing its gradient noise, boosting performance. More interestingly, it provides a unifying model for several neural network techniques, including kernel least-mean-square algorithms, kernel adaline, sliding-window kernel recursive-least squares (KRLS), and regularization networks. Therefore, many insights can be gained into the basic relations among them and the tradeoff between computation complexity and performance. Several simulations illustrate its wide applicability.

  7. A systematic analysis reveals an essential role for high-affinity iron uptake system, haemolysin and CFEM domain-containing protein in iron homoeostasis and virulence in Candida glabrata.

    PubMed

    Srivastava, Vivek Kumar; Suneetha, Korivi Jyothiraj; Kaur, Rupinder

    2014-10-01

    Iron is an essential nutrient for all living organisms and human pathogens employ a battery of factors to scavenge iron from the high-affinity iron-binding host proteins. In the present study, we have elucidated, via a candidate gene approach, major iron acquisition and homoeostatic mechanisms operational in an opportunistic human fungal pathogen Candida glabrata. Phenotypic, biochemical and molecular analysis of a set of 13 C. glabrata strains, deleted for proteins potentially implicated in iron metabolism, revealed that the high-affinity reductive iron uptake system is required for utilization of alternate carbon sources and for growth under both in vitro iron-limiting and in vivo conditions. Furthermore, we show for the first time that the cysteine-rich CFEM (common in fungal extracellular membranes) domain-containing cell wall structural protein, CgCcw14, and a putative haemolysin, CgMam3, are essential for maintenance of intracellular iron content, adherence to epithelial cells and virulence. Consistent with their roles in iron homoeostasis, mitochondrial aconitase activity was lower and higher in mutants disrupted for high-affinity iron transport, and haemolysin respectively. Additionally, we present evidence that the mitochondrial frataxin, CgYfh1, is pivotal to iron metabolism. Besides yielding insights into major in vitro and in vivo iron acquisition strategies, our findings establish high-affinity iron uptake mechanisms as critical virulence determinants in C. glabrata.

  8. RS-34 Phoenix In-Space Propulsion System Applied to Active Debris Removal Mission

    NASA Technical Reports Server (NTRS)

    Esther, Elizabeth A.; Burnside, Christopher G.

    2014-01-01

    In-space propulsion is a high percentage of the cost when considering Active Debris Removal mission. For this reason it is desired to research if existing designs with slight modification would meet mission requirements to aid in reducing cost of the overall mission. Such a system capable of rendezvous, close proximity operations, and de-orbit of Envisat class resident space objects has been identified in the existing RS-34 Phoenix. RS-34 propulsion system is a remaining asset from the de-commissioned United States Air Force Peacekeeper program; specifically the pressure-fed storable bi-propellant Stage IV Post Boost Propulsion System. The National Aeronautics and Space Administration (NASA) Marshall Space Flight Center (MSFC) gained experience with the RS-34 propulsion system on the successful Ares I-X flight test program flown in the Ares I-X Roll control system (RoCS). The heritage hardware proved extremely robust and reliable and sparked interest for further utilization on other potential in-space applications. Subsequently, MSFC has obtained permission from the USAF to obtain all the remaining RS-34 stages for re-use opportunities. The MSFC Advanced Concepts Office (ACO) was commissioned to lead a study for evaluation of the Rocketdyne produced RS-34 propulsion system as it applies to an active debris removal design reference mission for resident space object targets including Envisat. Originally designed, the RS-34 Phoenix provided in-space six-degrees-of freedom operational maneuvering to deploy payloads at multiple orbital locations. The RS-34 Concept Study lead by sought to further understand application for a similar orbital debris design reference mission to provide propulsive capability for rendezvous, close proximity operations to support the capture phase of the mission, and deorbit of single or multiple large class resident space objects. Multiple configurations varying the degree of modification were identified to trade for dry mass optimization and

  9. Comparison of adsorption and photo-Fenton processes for phenol and paracetamol removing from aqueous solutions: single and binary systems.

    PubMed

    Rad, Leila Roshanfekr; Haririan, Ismaeil; Divsar, Faten

    2015-02-05

    In the present study, adsorption and photo-Fenton processes have been compared for the removal of phenol and paracetamol from aqueous solutions in a single and binary systems. NaX nanozeolites and cobalt ferrite nanoparticles were used during adsorption and photo-Fenton processes, respectively. Both nanoparticles were synthesized using microwave heating method. The synthesized nanoparticles were characterized using powder X-ray diffraction (XRD) and scanning electronic microscopy (SEM) analysis. Based on results, more than 99% removing percentages of phenol and paracetamol were obtained during photo-Fenton process at initial concentrations of 10, 20, 50, 100 and 200 mg/L of phenol and paracetamol. Moreover, the complete removing of phenol and paracetamol was only achieved at lower initial concentrations than 10 mg/L for phenol and paracetamol during adsorption process. The results showed a significant dependence of the phenol and paracetamol removing on the initial concentrations of phenol and paracetamol for selection of process. The photo-Fenton process could be considered an alternative method in higher initial concentrations of phenol and paracetamol. However, the adsorption process due to economical issue was preferred for phenol and paracetamol removing at lower initial concentrations. The kinetic data of photo-Fenton and adsorption processes were well described using first-order and pseudo-second-order kinetic models. The results of phenol and paracetamol removing in a binary system confirmed the obtained results of single removing of phenol and paracetamol in selection of process.

  10. Comparison of adsorption and photo-Fenton processes for phenol and paracetamol removing from aqueous solutions: Single and binary systems

    NASA Astrophysics Data System (ADS)

    Rad, Leila Roshanfekr; Haririan, Ismaeil; Divsar, Faten

    2015-02-01

    In the present study, adsorption and photo-Fenton processes have been compared for the removal of phenol and paracetamol from aqueous solutions in a single and binary systems. NaX nanozeolites and cobalt ferrite nanoparticles were used during adsorption and photo-Fenton processes, respectively. Both nanoparticles were synthesized using microwave heating method. The synthesized nanoparticles were characterized using powder X-ray diffraction (XRD) and scanning electronic microscopy (SEM) analysis. Based on results, more than 99% removing percentages of phenol and paracetamol were obtained during photo-Fenton process at initial concentrations of 10, 20, 50, 100 and 200 mg/L of phenol and paracetamol. Moreover, the complete removing of phenol and paracetamol was only achieved at lower initial concentrations than 10 mg/L for phenol and paracetamol during adsorption process. The results showed a significant dependence of the phenol and paracetamol removing on the initial concentrations of phenol and paracetamol for selection of process. The photo-Fenton process could be considered an alternative method in higher initial concentrations of phenol and paracetamol. However, the adsorption process due to economical issue was preferred for phenol and paracetamol removing at lower initial concentrations. The kinetic data of photo-Fenton and adsorption processes were well described using first-order and pseudo-second-order kinetic models. The results of phenol and paracetamol removing in a binary system confirmed the obtained results of single removing of phenol and paracetamol in selection of process.

  11. Complications of Transfemoral Removal of Percutaneous Transfemorally Implanted Port-Catheter Systems

    SciTech Connect

    Yahiro, Yoshiyuki; Toyota, Naoyuki Kakizawa, Hideaki; Hieda, Masashi; Hirai, Nobuhiko; Naito, Akira; Ito, Katsuhide

    2006-10-15

    Our purpose is to evaluate the feasibility and safety of the withdrawal procedure of percutaneous transfemorally implanted port-catheter systems. Thirty-seven patients (17.7%) underwent the withdrawal procedure of this port-catheter system among 209 patients. The reasons for withdrawal were as follows: termination of intra-arterial chemotherapy (n = 7), obstruction of hepatic artery (n = 5), port infection (n = 4), catheter infection (n = 4), catheter obstruction (n = 4), lower-limb palsy and pain (n = 2), exposure of the port due to skin defect (n = 2), patient's desire (n = 2), side effect of chemotherapy (n = 1), no effectiveness of chemotherapy (n = 1), hematoma at the puncture site (n = 1), duodenum perforation by the catheter (n = 1), intermittent claudication due to severe stenosis of right common iliac artery (n = 1), dissection of common hepatic artery (n = 1), and broken catheter (n = 1). In thirty-four of the 37 cases, the port-catheter system was successfully withdrawn without any complications. Clinical success rate was 91.9%. Complications occurred in three cases (8.1%), which were a pseudoaneurysm, thromboembolism of the right common iliac artery, and continuous bleeding from the subcutaneous pocket where the port system was placed for 1 month. In 15 cases, correction of the catheter tip or exchange for dislocation of the tip had to be done without withdrawal. It is not rare to withdraw port-catheter systems in cases of infection or hematoma around the system. Although withdrawal of a percutaneous transfemorally implanted port-catheter system is a relatively safe procedure, the port-catheter system should not be removed unless absolutely indicated.

  12. Adjoint affine fusion and tadpoles

    NASA Astrophysics Data System (ADS)

    Urichuk, Andrew; Walton, Mark A.

    2016-06-01

    We study affine fusion with the adjoint representation. For simple Lie algebras, elementary and universal formulas determine the decomposition of a tensor product of an integrable highest-weight representation with the adjoint representation. Using the (refined) affine depth rule, we prove that equally striking results apply to adjoint affine fusion. For diagonal fusion, a coefficient equals the number of nonzero Dynkin labels of the relevant affine highest weight, minus 1. A nice lattice-polytope interpretation follows and allows the straightforward calculation of the genus-1 1-point adjoint Verlinde dimension, the adjoint affine fusion tadpole. Explicit formulas, (piecewise) polynomial in the level, are written for the adjoint tadpoles of all classical Lie algebras. We show that off-diagonal adjoint affine fusion is obtained from the corresponding tensor product by simply dropping non-dominant representations.

  13. Effect of basic operating parameters on biological phosphorus removal in a continuous-flow anaerobic-anoxic activated sludge system.

    PubMed

    Kapagiannidis, A G; Zafiriadis, I; Aivasidis, A

    2012-03-01

    A continuous-flow anaerobic-anoxic (A2) activated sludge system was operated for efficient enhanced biological phosphorus removal (EBPR). Because of the system configuration with no aeration zones, phosphorus (P) uptake takes place solely under anoxic conditions with simultaneous denitrification. Basic operating conditions, namely biomass concentration, influent carbon to phosphorus ratio and anaerobic retention time were chosen as variables in order to assess their impact on the system performance. The experimental results indicated that maintenance of biomass concentration above 2,500 mg MLVSS/L resulted in the complete phosphate removal from the influent (i.e. 15 mg PO(4) (3-)-P/L) for a mean hydraulic residence time (HRT) of 15 h. Additionally, by increasing the influent COD/P ratio from 10 to 20 g/g, the system P removal efficiency was improved although the experimental results indicated a possible enhancement of the competition between phosphorus accumulating organisms (PAOs) and other microbial populations without phosphorus uptake ability. Moreover, because of the use of acetate (i.e. easily biodegradable substrate) as the sole carbon source in the system feed, application of anaerobic retention times greater than 2 h resulted in no significant release of additional P in the anaerobic zone and no further amelioration of the system P removal efficiency. The application of anoxic P removal resulted in more than 50% reduction of the organic carbon necessitated for nitrogen and phosphorus removal when compared to a conventional EBPR system incorporating aerobic phosphorus removal.

  14. A Study on the Development of a Robot-Assisted Automatic Laser Hair Removal System

    PubMed Central

    Lim, Hyoung-woo; Park, Sungwoo; Noh, Seungwoo; Lee, Dong-Hun; Yoon, Chiyul; Koh, Wooseok; Kim, Youdan; Chung, Jin Ho; Kim, Hee Chan

    2014-01-01

    Abstract Background and Objective: The robot-assisted automatic laser hair removal (LHR) system is developed to automatically detect any arbitrary shape of the desired LHR treatment area and to provide uniform laser irradiation to the designated skin area. Methods: For uniform delivery of laser energy, a unit of a commercial LHR device, a laser distance sensor, and a high-resolution webcam are attached at the six axis industrial robot's end-effector, which can be easily controlled using a graphical user interface (GUI). During the treatment, the system provides real-time treatment progress as well as the total number of “pick and place” automatically. Results: During the test, it was demonstrated that the arbitrary shapes were detected, and that the laser was delivered uniformly. The localization error test and the area-per-spot test produced satisfactory outcome averages of 1.04 mm error and 38.22 mm2/spot, respectively. Conclusions: Results showed that the system successfully demonstrated accuracy and effectiveness. The proposed system is expected to become a promising device in LHR treatment. PMID:25343281

  15. The effect of free nitrous acid on key anaerobic processes in enhanced biological phosphorus removal systems.

    PubMed

    Ye, Liu; Pijuan, Maite; Yuan, Zhiguo

    2013-02-01

    In this study, the effect of nitrite/FNA on the anaerobic metabolism of polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) is investigated. The results clearly show that FNA has a detrimental effect on the acetate uptake rate by both PAOs and GAOs, but this adverse effect is much stronger on PAOs than on GAOs. Also, when FNA was increased, phosphate release to acetate uptake ratio by PAOs increased substantially (250-300% compared to control), which was accompanied by decreases (40-60%) in glycogen degradation and PHA production to VFA uptake. In contrast, these ratios for GAOs remained constant or increased slightly towards the highest FNA concentration applied. These results indicate that the anaerobic metabolism of PAOs is more adversely affected than that of GAOs when FNA is present. This might provide a competitive advantage to GAOs over PAOs in enhanced biological phosphorus removal systems when nitrite is present.

  16. Prediction of intracellular storage polymers using quantitative image analysis in enhanced biological phosphorus removal systems.

    PubMed

    Mesquita, Daniela P; Leal, Cristiano; Cunha, Jorge R; Oehmen, Adrian; Amaral, A Luís; Reis, Maria A M; Ferreira, Eugénio C

    2013-04-03

    The present study focuses on predicting the concentration of intracellular storage polymers in enhanced biological phosphorus removal (EBPR) systems. For that purpose, quantitative image analysis techniques were developed for determining the intracellular concentrations of PHA (PHB and PHV) with Nile blue and glycogen with aniline blue staining. Partial least squares (PLS) were used to predict the standard analytical values of these polymers by the proposed methodology. Identification of the aerobic and anaerobic stages proved to be crucial for improving the assessment of PHA, PHB and PHV intracellular concentrations. Current Nile blue based methodology can be seen as a feasible starting point for further enhancement. Glycogen detection based on the developed aniline blue staining methodology combined with the image analysis data proved to be a promising technique, toward the elimination of the need for analytical off-line measurements.

  17. An acid-gas removal system for upgrading subquality natural gas

    SciTech Connect

    Palla, N.; Lee, A.L.; Leppin, D.; Shoemaker, H.D.; Hooper, H.M.; Emmrich, G.; Moore, T.F.

    1996-09-01

    The objective of this project is to develop systems to reduce the cost of treating subquality natural gas. Based on over 1,000 laboratory experiments on vapor-liquid equilibria and mass transfer and simulation studies, the use of N-Formyl Morpholine as a solvent together with structured packings has the following advantages: high capacity for H{sub 2}S and CO{sub 2} removal; little or no refrigeration required; less loss of hydrocarbons (CH{sub 4}, C{sub 2}-C{sub 6}); and dehydration potential. To verify these findings and to obtain additional data base for scale-up, a field test unit capable of processing 1MMSCF/d of natural gas has been installed at the Shell Western E and P Inc. (SWEPI) Fandango processing plant site. The results of the testing at the Fandango site will be presented when available.

  18. Process and system for removing sulfur from sulfur-containing gaseous streams

    DOEpatents

    Basu, Arunabha [Aurora, IL; Meyer, Howard S [Hoffman Estates, IL; Lynn, Scott [Pleasant Hill, CA; Leppin, Dennis [Chicago, IL; Wangerow, James R [Medinah, IL

    2012-08-14

    A multi-stage UCSRP process and system for removal of sulfur from a gaseous stream in which the gaseous stream, which contains a first amount of H.sub.2S, is provided to a first stage UCSRP reactor vessel operating in an excess SO.sub.2 mode at a first amount of SO.sub.2, producing an effluent gas having a reduced amount of SO.sub.2, and in which the effluent gas is provided to a second stage UCSRP reactor vessel operating in an excess H.sub.2S mode, producing a product gas having an amount of H.sub.2S less than said first amount of H.sub.2S.

  19. Rapid removal of nitrobenzene in a three-phase ozone loaded system with gas-liquid-liquid

    USGS Publications Warehouse

    Li, Shiyin; Zhu, Jiangpeng; Wang, Guoxiang; Ni, Lixiao; Zhang, Yong; Green, Christopher T.

    2015-01-01

    This study explores the removal rate of nitrobenzene (NB) using a new gas-liquid-liquid (G-L-L) three-phase ozone loaded system consisting of a gaseous ozone, an aqueous solvent phase, and a fluorinated solvent phase (perfluorodecalin, or FDC). The removal rate of NB was quantified in relation to six factors including 1) initial pH, 2) initial NB dosage, 3) gaseous ozone dosage, 4) free radical scavenger, 5) FDC pre-aerated gaseous ozone, and 6) reuse of FDC. The NB removal rate is positively affected by the first three factors. Compared with the conventional gas-liquid (water) (G-L) two-phase ozonation system, the free radical scavenger (tertiary butyl alcohol) has much less influence on the removal rate of NB in the G-L-L system. The FDC loaded ozone acts as an ozone reservoir and serves as the main reactive phase in the G-L-L three-phase system. The reuse of FDC has little influence on the removal rate of NB. These experimental results suggest that the oxidation efficiency of ozonation in the G-L-L three-phase system is better than that in the conventional G-L two-phase system.

  20. A global benchmark study using affinity-based biosensors

    PubMed Central

    Rich, Rebecca L.; Papalia, Giuseppe A.; Flynn, Peter J.; Furneisen, Jamie; Quinn, John; Klein, Joshua S.; Katsamba, Phini S.; Waddell, M. Brent; Scott, Michael; Thompson, Joshua; Berlier, Judie; Corry, Schuyler; Baltzinger, Mireille; Zeder-Lutz, Gabrielle; Schoenemann, Andreas; Clabbers, Anca; Wieckowski, Sebastien; Murphy, Mary M.; Page, Phillip; Ryan, Thomas E.; Duffner, Jay; Ganguly, Tanmoy; Corbin, John; Gautam, Satyen; Anderluh, Gregor; Bavdek, Andrej; Reichmann, Dana; Yadav, Satya P.; Hommema, Eric; Pol, Ewa; Drake, Andrew; Klakamp, Scott; Chapman, Trevor; Kernaghan, Dawn; Miller, Ken; Schuman, Jason; Lindquist, Kevin; Herlihy, Kara; Murphy, Michael B.; Bohnsack, Richard; Andrien, Bruce; Brandani, Pietro; Terwey, Danny; Millican, Rohn; Darling, Ryan J.; Wang, Liann; Carter, Quincy; Dotzlaf, Joe; Lopez-Sagaseta, Jacinto; Campbell, Islay; Torreri, Paola; Hoos, Sylviane; England, Patrick; Liu, Yang; Abdiche, Yasmina; Malashock, Daniel; Pinkerton, Alanna; Wong, Melanie; Lafer, Eileen; Hinck, Cynthia; Thompson, Kevin; Primo, Carmelo Di; Joyce, Alison; Brooks, Jonathan; Torta, Federico; Bagge Hagel, Anne Birgitte; Krarup, Janus; Pass, Jesper; Ferreira, Monica; Shikov, Sergei; Mikolajczyk, Malgorzata; Abe, Yuki; Barbato, Gaetano; Giannetti, Anthony M.; Krishnamoorthy, Ganeshram; Beusink, Bianca; Satpaev, Daulet; Tsang, Tiffany; Fang, Eric; Partridge, James; Brohawn, Stephen; Horn, James; Pritsch, Otto; Obal, Gonzalo; Nilapwar, Sanjay; Busby, Ben; Gutierrez-Sanchez, Gerardo; Gupta, Ruchira Das; Canepa, Sylvie; Witte, Krista; Nikolovska-Coleska, Zaneta; Cho, Yun Hee; D’Agata, Roberta; Schlick, Kristian; Calvert, Rosy; Munoz, Eva M.; Hernaiz, Maria Jose; Bravman, Tsafir; Dines, Monica; Yang, Min-Hsiang; Puskas, Agnes; Boni, Erica; Li, Jiejin; Wear, Martin; Grinberg, Asya; Baardsnes, Jason; Dolezal, Olan; Gainey, Melicia; Anderson, Henrik; Peng, Jinlin; Lewis, Mark; Spies, Peter; Trinh, Quyhn; Bibikov, Sergei; Raymond, Jill; Yousef, Mohammed; Chandrasekaran, Vidya; Feng, Yuguo; Emerick, Anne; Mundodo, Suparna; Guimaraes, Rejane; McGirr, Katy; Li, Yue-Ji; Hughes, Heather; Mantz, Hubert; Skrabana, Rostislav; Witmer, Mark; Ballard, Joshua; Martin, Loic; Skladal, Petr; Korza, George; Laird-Offringa, Ite; Lee, Charlene S.; Khadir, Abdelkrim; Podlaski, Frank; Neuner, Phillippe; Rothacker, Julie; Rafique, Ashique; Dankbar, Nico; Kainz, Peter; Gedig, Erk; Vuyisich, Momchilo; Boozer, Christina; Ly, Nguyen; Toews, Mark; Uren, Aykut; Kalyuzhniy, Oleksandr; Lewis, Kenneth; Chomey, Eugene; Pak, Brian J.; Myszka, David G.

    2013-01-01

    To explore the variability in biosensor studies, 150 participants from 20 countries were given the same protein samples and asked to determine kinetic rate constants for the interaction. We chose a protein system that was amenable to analysis using different biosensor platforms as well as by users of different expertise levels. The two proteins (a 50-kDa Fab and a 60-kDa glutathione S-transferase [GST] antigen) form a relatively high-affinity complex, so participants needed to optimize several experimental parameters, including ligand immobilization and regeneration conditions as well as analyte concentrations and injection/dissociation times. Although most participants collected binding responses that could be fit to yield kinetic parameters, the quality of a few data sets could have been improved by optimizing the assay design. Once these outliers were removed, the average reported affinity across the remaining panel of participants was 620 pM with a standard deviation of 980 pM. These results demonstrate that when this biosensor assay was designed and executed appropriately, the reported rate constants were consistent, and independent of which protein was immobilized and which biosensor was used. PMID:19133223

  1. Laboratory tests in support of the MSRE reactive gas removal system

    SciTech Connect

    Rudolph, J.C.; Del Cul, G.D.; Caja, J.; Toth, L.M.; Williams, D.F.; Thomas, K.S.; Clark, D.E.

    1997-07-01

    The Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory has been shut down since December 1969, at which time the molten salt mixture of LiF-BeF{sub 2}-ZrF{sub 4}-{sup 233}UF{sub 4} (64.5-30.3-5.0-0.13 mol%) was transferred to fuel salt drain tanks for storage. In the late 1980s, increased radiation in one of the gas lines from the drain tank was attributed to {sup 233}UF{sub 6}. In 1994 two gas samples were withdraw (from a gas line in the Vent House connecting to the drain tanks) and analyzed. Surprisingly, 350 mm Hg of F{sub 2}, 70 mm Hg of UF{sub 6}, and smaller amounts of other gases were found in both of the samples. To remote this gas from above the drain tanks and all of the associated piping, the reactive gas removal system (RGRS) was designed. This report details the laboratory testing of the RGRS, using natural uranium, prior to its implementation at the MSRE facility. The testing was performed to ensure that the equipment functioned properly and was sufficient to perform the task while minimizing exposure to personnel. In addition, the laboratory work provided the research and development effort necessary to maximize the performance of the system. Throughout this work technicians and staff who were to be involved in RGRS operation at the MSRE site worked directly with the research staff in completing the laboratory testing phase. Consequently, at the end of the laboratory work, the personnel who were to be involved in the actual operations had acquired all of the training and experience necessary to continue with the process of reactive gas removal.

  2. Removal efficiency and balance of nitrogen in a recirculating aquaculture system integrated with constructed wetlands.

    PubMed

    Zhong, Fei; Liang, Wei; Yu, Tao; Cheng, Shui P; He, Feng; Wu, Zhen B

    2011-01-01

    The nitrogen (N) balance for aquaculture is an important aspect, especially in China, and it is attributed to the eutrophication in many freshwater bodies. In recent years, constructed wetlands (CWs) have been widely used in wastewater treatment and ecosystem restoration. A recirculating aquaculture system (RAS) consisting of CWs and 4 fish ponds was set up in Wuhan, China. Channel catfish (Ictalurus punctatus) fingerlings were fed for satiation daily for 168 days with 2 diets containing 5.49 % and 6.53 % nitrogen, respectively. The objectives of this study were to investigate the N budget in the RAS, and try to find out the feasibility of controlling N accumulation in the fish pond. It is expected that the study can provide a mass balance for the fate of N in the eco-friendly treatment system to avoid eutrophication. The results showed that the removal rates of ammonia (NH(+)(4)-N), sum of nitrate & nitrite (NO(-)(X)-N), and total nitrogen (TN) by the CWs were 20-55%, 38-84 % and 39-57 %, respectively. Denitrification in the CWs was the main pathway of nitrogen loss (41.67 %). Nitrogen accumulation in pond water and sediment accounted for 3.39 % and 12.65 % of total nitrogen loss, respectively. The nitrogen removal efficiency and budget showed that the CW could be used to control excessive nitrogen accumulation in fish ponds. From the viewpoint of the nitrogen pollution control, the RAS combined with the constructed wetland can be applied to ensure the sustainable development for aquaculture.

  3. Long-term effect of low concentration Cr(VI) on P removal in granule-based enhanced biological phosphorus removal (EBPR) system.

    PubMed

    Fang, Jing; Su, Bin; Sun, Peide; Lou, Juqing; Han, Jingyi

    2015-02-01

    In light of the fact that most wastewater in China contained both industrial and domestic wastewater, a 52-d systematical investigation was conducted on the long-term effect of low concentration Cr(VI) (0.3-0.8 mg L(-1)) on P removal performance of granule-based EBPR system in this study. The mechanisms were likewise discussed. Results showed that high Cr(VI) concentration (⩾0.5 mg L(-1)) could significantly inhibit P removal, while this phenomenon was not found when Cr(VI) concentration was less than (or equal to) 0.4 mg L(-1). Most of the granules was disintegrated and filamentous bacteria overgrew inducing sludge bulking occurred at 0.7 mg L(-1) Cr(VI). During the exposure test, the abundance of poly-phosphate-accumulating organisms (PAOs) significantly decreased while the populations of glycogen accumulating organisms (GAOs) and other bacteria increased. Both production and degradation of poly-β-hydroxyakanoates (PHAs) were apparently inhibited. An improved polysaccharide/protein (PS/PN) ratio was observed with the increasing Cr(VI) concentration, implying excessive polysaccharide was secreted by microorganisms to support its resistance to the toxicity of Cr(VI). Besides, good linear regression between PS/PN ratio and the granule size (R(2)=-0.86, p<0.01) was obtained, indicating that high PS/PN was adverse to granule stability. Correlation analysis indicated that the accumulation of granules intracellular Cr was directly responsible for the observed inhibitory effect on P removal process. The long-term Cr(VI) treatment had irreversible effects on granule-based EBPR system as it could not revive after a 16-d recovery process.

  4. Removal of chemical oxygen demand and dissolved nutrients by a sunken lawn infiltration system during intermittent storm events.

    PubMed

    Hou, Lizhu; Yang, Huan; Li, Ming

    2014-01-01

    Urban surface water runoff typically contains high but varying amounts of organic matter and nutrients that require removal before reuse. Infiltration systems such as sunken lawns can improve water quality. However, there is currently insufficient information describing the treatment efficiency of lawn-based infiltration systems. In this study, novel sunken lawn infiltration systems (SLISs) were designed and their pollutant removal effectiveness was assessed. The results revealed that SLISs with Poa pratensis and Lolium perenne effectively removed most chemical oxygen demand (CODCr) and dissolved nutrients. Average CODCr, total nitrogen (TN), ammonium-nitrogen (NH4(+)-N) and total phosphorus (TP) concentrations were reduced by 78.93, 66.64, 71.86 and 75.83%, respectively, and the corresponding effluent concentrations met the standard for urban miscellaneous water consumption in China. The NH4(+)-N in the synthetic runoff was shown to be removed by adsorption during the stormwater dosing and nitrification during subsequent dry days, as well as through uptake by plants. Phosphorus was mainly removed by adsorption and chemical precipitation. The NH4(+)-N and phosphorus Langmuir isotherm model fitted the clay loam soil adsorption process better than the Freundlich model. Overall, these results indicate that an SLIS provides an alternative means of removing runoff pollutants owing to its efficiency, easy operation and maintenance.

  5. A comparison between the theory and reality of full-scale step-feed nutrient removal systems.

    PubMed

    Johnson, B R; Goodwin, S; Daigger, G T; Crawford, G V

    2005-01-01

    Capacity enhancement and volume reduction benefits of step-feeding fully aerobic bioreactors has been well documented. Application of step-feed technology to biological nutrient removal (BNR) systems, particularly those removing nitrogen alone or both nitrogen and phosphorus, is relatively new to the industry. In recent years, a number of full-scale step-feed facilities have been brought into service. This paper reviews nine full-scale step-feed biological nutrient removal systems--both nitrogen removal alone, and nitrogen and phosphorus removal. The objective is to compare the theoretical benefits of such systems with their actual operation. The predicted benefits of reduced bioreactor volume or increased process capacity, reduced energy usage, more robust nitrification performance, and the flexibility to tune (or de-tune) nitrification efficiency were verified in full-scale systems. Equations are also presented that may be used in the prediction of step-feed benefits. There are two primary drivers for considering a step-feed biological reactor system: 1. Reduced bioreactor volume for a defined capacity or performance or increased process capacity given a fixed bioreactor volume. 2. More robust nitrification performance. Full-scale operation of these step-feed nutrient removal systems provides a real world basis for the claimed benefits of step-feed operation. These systems have uniformly shown additional capacity. A number of them have also exhibited more robust performance, especially during storms. Where possible, side-by-side comparisons of full-scale step-feed systems with non-step-feed systems have exhibited greater process reliability and flexibility.

  6. Persistent Spinal Headache After Removal of Intrathecal Drug Delivery System: A Case Report and Review of Literature

    PubMed Central

    Kurnutala, Lakshmi N.; Kim, David; Sayeed, Huma; Sibai, Nabil

    2015-01-01

    Introduction: To report and discuss the spinal headache following insertion and removal of intrathecal drug delivery system in patients with chronic pain disorders. Case Presentation: Intrathecal drug delivery system (IDDS) was initially used for the management of chronic malignant pain; it has since been used to manage pain from other nonmalignant conditions as well. Spinal headache is one of the complications during the trial, permanent placement and after removal of intrathecal drug delivery catheter systems. A 48-year-male patient with chronic pain disorder developed a refractory spinal headache after removing the intrathecal drug delivery system requiring a surgical intervention to resolve the problem. Conclusions: Conservative management is successful in the vast majority of patients with spinal headache. Interventional procedures are required in a small fraction of patients for symptomatic relief. PMID:26587409

  7. Evaluation of three state-of-the-art water-jet systems for cutting/removing concrete

    NASA Astrophysics Data System (ADS)

    Pace, C. E.

    1982-09-01

    This report documents a demonstration project to evaluate the capability of three waterjet systems for cutting or removing concrete or both. The Corps of Engineers is interested in the potential of this technology for such applications as rapid cutting of bomb-damaged selection of airfield pavement and removing of deteriorated sections of concrete structures at Civil Works projects. Because water-jet systems are capable of transmitting, without mechanical constraint, all of the available horsepower of their power sources into the concrete cutting/removing operation, they may prove to be an extremely efficient means of conducting such operations. The low-pressure water jets were able to cut a 6-in. slot in the concrete for a distance of 1-1/2 ft. in a period of 24 minutes (a rate of 6.4 ft. per hour). The relatively high-pressure water jet cut at rates of 9.6 ft. per hour for shallow cuts (less than 5 in.) and 3 ft. per hour for deeper cuts (greater than 5 in.). In addition, one of the low-pressure systems was used to remove some surface concrete. The results of this evaluation indicate that, although these water-jet systems did not demonstrate a capability for efficiently cutting concrete airfield pavements, the technology has potential. The low-pressure system demonstrated a capability for removing surface concrete efficiently.

  8. Enhanced azo dye removal through anode biofilm acclimation to toxicity in single-chamber biocatalyzed electrolysis system.

    PubMed

    Wang, You-Zhao; Wang, Ai-Jie; Liu, Wen-Zong; Sun, Qian

    2013-08-01

    Azo dye is widely used in printing and dyeing process as one of refractory wastewaters for its high chroma, stable chemical property and toxicity for aquatic organism. Biocatalyzed electrolysis system (BES) is a new developed technology to degrade organic waste in bioanode and recover recalcitrant contaminants in cathode with effective decoloration. The ion exchange membrane (IEM) separate anode and cathode for biofilm formation protection. Azo removal efficiency was up to 60.8%, but decreased to 20.5% when IEM was removed. However, expensive ion exchange membrane (IEM) not suitable for further practical application, bioelectrochemical activity of bioanode is sensitive to the toxicity of azo dye. A gradient increase of azo dye concentration was used to acclimate anode biofilm to pollutant toxicity. The azo removal efficiency can be enhanced to 73.3% in 10h reaction period after acclimation. The highest removal efficiency reached 83.7% and removal rates were increased to 8.37 from 3.04 g/h/L of dual-chamber. That indicated the feasibility for azo dye removal by single-chamber BES. The IEM cancellation not only decreased the internal resistance, but increased the current density and azo dye removal.

  9. Evaluation of acrylamide-removing properties of two Lactobacillus strains under simulated gastrointestinal conditions using a dynamic system.

    PubMed

    Rivas-Jimenez, L; Ramírez-Ortiz, K; González-Córdova, A F; Vallejo-Cordoba, B; Garcia, H S; Hernandez-Mendoza, A

    2016-09-01

    The aim of this study was to evaluate the capability of Lactobacillus reuteri NRRL 14171 and Lactobacillus casei Shirota to remove dietary acrylamide (AA) under simulated gastrointestinal conditions using a dynamic system. The effects of different AA levels or bacteria concentration on toxin removal by Lactobacillus strains were assessed. Thereafter, AA-removing capability of bacteria strains under either fasting or postprandial simulated gastrointestinal conditions was evaluated. Commercial potato chips were analyzed for their AA content, and then used as a food model. Average AA content (34,162μg/kg) in potato chips exceeded by ca. 34-fold the indicative values recommended by the EU. Toxin removal ability was dependent on AA content and bacterial cell concentration. A reduction on bacterial viability was observed in the food model and at the end of both digestive processes evaluated. However, bacteria survived in enough concentrations to remove part of the toxin (32-73%). Both bacterial strains were able to remove AA under different simulated gastrointestinal conditions, being L. casei Shirota the most effective (ca. 70% removal). These findings confirmed the risk of potato chips as dietary AA exposure for consumers, and that strains of the genus Lactobacillus could be employed to reduce the bioavailability of dietary AA.

  10. Reliability and Maintainability Analysis for the Amine Swingbed Carbon Dioxide Removal System

    NASA Technical Reports Server (NTRS)

    Dunbar, Tyler

    2016-01-01

    I have performed a reliability & maintainability analysis for the Amine Swingbed payload system. The Amine Swingbed is a carbon dioxide removal technology that has gone through 2,400 hours of International Space Station on-orbit use between 2013 and 2016. While the Amine Swingbed is currently an experimental payload system, the Amine Swingbed may be converted to system hardware. If the Amine Swingbed becomes system hardware, it will supplement the Carbon Dioxide Removal Assembly (CDRA) as the primary CO2 removal technology on the International Space Station. NASA is also considering using the Amine Swingbed as the primary carbon dioxide removal technology for future extravehicular mobility units and for the Orion, which will be used for the Asteroid Redirect and Journey to Mars missions. The qualitative component of the reliability and maintainability analysis is a Failure Modes and Effects Analysis (FMEA). In the FMEA, I have investigated how individual components in the Amine Swingbed may fail, and what the worst case scenario is should a failure occur. The significant failure effects are the loss of ability to remove carbon dioxide, the formation of ammonia due to chemical degradation of the amine, and loss of atmosphere because the Amine Swingbed uses the vacuum of space to regenerate the Amine Swingbed. In the quantitative component of the reliability and maintainability analysis, I have assumed a constant failure rate for both electronic and nonelectronic parts. Using this data, I have created a Poisson distribution to predict the failure rate of the Amine Swingbed as a whole. I have determined a mean time to failure for the Amine Swingbed to be approximately 1,400 hours. The observed mean time to failure for the system is between 600 and 1,200 hours. This range includes initial testing of the Amine Swingbed, as well as software faults that are understood to be non-critical. If many of the commercial parts were switched to military-grade parts, the expected

  11. The lid of the container for the Mobile Base System, part of the Canadian arm, is prepared for remov

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Inside the Space Station Processing Facility, workers prepare to remove the lid of a container holding the Mobile Base System (MBS). The MBS is part of the Canadian Space Agency's Space Station Remote Manipulator System (SSRMS), which is part of the payload on mission STS-100 to the International Space Station.

  12. REMOVAL OF MICROBIAL CONTAMINANTS IN DRINKING WATER: KOCH MEMBRANE SYSTEMS, HF-82-35-PMPW™ ULTRAFILTRATION MEMBRANE

    EPA Science Inventory

    Two Koch Membrane Systems HF-82-35-PMPW ultrafiltration membrane cartridges were tested for removal of viruses, bacteria, and protozoan cysts at NSF’s Drinking Water Treatment Systems Laboratory. The ETV testing was conducted as part of a series of evaluations of the Expeditiona...

  13. Smooth affine shear tight frames: digitization and applications

    NASA Astrophysics Data System (ADS)

    Zhuang, Xiaosheng

    2015-08-01

    In this paper, we mainly discuss one of the recent developed directional multiscale representation systems: smooth affine shear tight frames. A directional wavelet tight frame is generated by isotropic dilations and translations of directional wavelet generators, while an affine shear tight frame is generated by anisotropic dilations, shears, and translations of shearlet generators. These two tight frames are actually connected in the sense that the affine shear tight frame can be obtained from a directional wavelet tight frame through subsampling. Consequently, an affine shear tight frame indeed has an underlying filter bank from the MRA structure of its associated directional wavelet tight frame. We call such filter banks affine shear filter banks, which can be designed completely in the frequency domain. We discuss the digitization of affine shear filter banks and their implementations: the forward and backward digital affine shear transforms. Redundancy rate and computational complexity of digital affine shear transforms are also investigated in this paper. Numerical experiments and comparisons in image/video processing show the advantages of digital affine shear transforms over many other state-of-art directional multiscale representation systems.

  14. Radiotherapy planning of the pelvis using distortion corrected MR images: the removal of system distortions

    NASA Astrophysics Data System (ADS)

    Tanner, S. F.; Finnigan, D. J.; Khoo, V. S.; Mayles, P.; Dearnaley, D. P.; Leach, M. O.

    2000-08-01

    Image distortion is an important consideration in the use of magnetic resonance (MR) images for radiotherapy planning. The distortion is a consequence of system distortion (arising from main magnetic field inhomogeneity and nonlinearities in the applied magnetic field gradients) and of effects arising from the object/patient being imaged. A two-stage protocol has been developed to correct both system- and object-induced distortion in pelvic images which incorporates measures to maintain the quality, accuracy and consistency of the imaging and correction procedures. The first stage of the correction procedure is described here and involves the removal of system distortion. Object- (patient-) induced effects will be described in a subsequent work. Images are acquired with the patient lying on a flat rigid bed, which reproduces treatment conditions. A frame of marker tubes surrounding the patient and attached to the bed provides quality assurance data in each image. System distortions in the three orthogonal planes are mapped using a separate phantom, which fits closely within the quality control frame. Software has been written which automates the measurement and checking of the many marker positions which the test objects generate and which ensures that patient data are acquired using a consistent imaging protocol. Results are presented which show that the scanner and the phantoms used in measuring distortion give highly reproducible results with mean changes of the order of 0.1 mm between repeated measurements of marker positions in the same imaging session. Effective correction for in-plane components of system distortion is demonstrated.

  15. Removal of metal ions by Phormidium bigranulatum (cyanobacteria)-dominated mat in batch and continuous flow systems.

    PubMed

    Kumar, Dhananjay; Rai, Jyoti; Gaur, J P

    2012-01-01

    Live Phormidium bigranulatum-dominated mat successfully removed Pb(II), Cu(II) and Cd(II) from aqueous solution. Percent metal removal approached equilibrium within 4h, independent of mat thickness (0.2-1.6 mm), in batch system. But % metal removal increased with increase in mat thickness due to enhancement of biomass, which provided more metal binding sites. Metal accumulation decreased with increase in mat thickness due to lessened metal availability vis-à-vis biomass. Metal removal (%) increased with increasing mat area, but decreased with increasing metal concentration in the solution. In continuous flow system, metal accumulation increased with increasing volume of single or multi-metal solution passed over the mat. The mat removed all the tested metals from the multi-metal solution with almost the same efficiency. The maximum removal of the test metals occurred at the lowest tested flow rate. Raceway type ponds can be employed for large-scale use of Phormidium mat in bioremediation of metalliferous wastewaters.

  16. Removal performance of nitrogen and endocrine-disrupting pesticides simultaneously in the enhanced biofilm system for polluted source water pretreatment.

    PubMed

    Feng, Li-Juan; Yang, Guang-Feng; Zhu, Liang; Xu, Xiang-Yang

    2014-10-01

    The removal performances of nitrogen and trace levels of endocrine-disrupting pesticides (cypermethrin and chlorpyrifos) were studied in the enhanced biofilm pretreatment system at various substrates concentrations and dissolve oxygen (DO) niches. No significant change of EDPs removal occurred with the increased feed of ammonia nitrogen in aerobic batch tests or nitrate in anaerobic batch reactors, but significantly enhanced via reed addition both in aerobic and anaerobic conditions. Simultaneously enhanced denitrification and EDPs removal were achieved in the anoxic niche with reed addition. The results of denaturing gradient gel electrophoresis (DGGE) indicated that new bands appeared, and some bands became more intense with the reed addition. Sequences analysis showed that the dominant species belonged to Methylophilaceae, Hyphomicrobium, Bacillus and Thauera, which were related to the nitrogen or EDPs removals. In addition, the growth of functional heterotrophic microbes may be promoted via reed addition.

  17. In Vitro Evaluation of a Rheolytic Thrombectomy System for Clot Removal from Five Different Temporary Vena Cava Filters

    SciTech Connect

    Buecker, Arno; Neuerburg, Joerg; Schmitz-Rode, Thomas; Vorwerk, Dierk; Guenther, Rolf W.

    1997-11-15

    Purpose: To evaluate the feasibility of thrombus removal from temporary vena cava filters using a rheolytic thrombectomy device and to assess the embolization rate of this procedure. Methods: Five temporary vena cava filters together with porcine thrombi were placed in a vena cava flow model (semitranslucent silicone tube of 23 mm diameter, pulsatile flow at a mean flow rate of 4 L/min). A rheolytic thrombectomy system (Hydrolyser) was used with a 9 Fr guiding catheter to remove the clots. The effluent was passed through filters of different size and the amount of embolized particles as well as the remaining thrombus were measured. Results: Thrombus removal rates ranged from 85% to 100%. Embolization rates between 47% and 60% were calculated for the different filters. Conclusion: The Hydrolyser is able to remove sufficiently high amounts of thrombus from temporary vena cava filters. However, the amount of embolized particles makes it impossible to utilize this method without special precautions against embolization.

  18. Mechanistic Determination of Nitrogen Removal By Advanced Soil-Based Wastewater Treatment Systems Using 15n Isotopes

    NASA Astrophysics Data System (ADS)

    Cooper, J.; Loomis, G.; Kalen, D.; Boving, T. B.; Morales, I.; Amador, J.

    2014-12-01

    Current levels of nitrogen removal by onsite wastewater treatment systems (OWTS) are inadequate, with release of N from OWTS contributing to environmental N pollution, especially in coastal zones where aquatic ecosystems are sensitive to eutrophication. Current mechanistic understand of N removal are limited and mainly attributed to denitrification in the drainfield. Loss of N from N2O production during nitrification, a sparsely researched topic, may be a significant mechanism in advanced OWTS systems that enhance O2 diffusion by sand filter pre-treatment, shallow placement of infiltrative areas and timed dosing controls to prevent drainfield saturation. Replicate (n=3) intact soil mesocosms were used with 15N isotope to evaluate the effectiveness and mechanisms of N removal in drainfields with a conventional wastewater delivery (pipe-and-stone, P&S) compared to two advanced types of drainfields, pressurized shallow narrow drainfield (SND) and Geomat (GEO), a variation of a SND drainfield. Over the 11 day experiment, dissolved O2 was 1.6 mg/L for P&S and 3.0 mg/L for SND and GEO. Removal of total N was 13.5% for P&S, 4.8% for SND and 5.4% for GEO. 15NH4 labeled nitrogen inputs to drainfields were transformed primarily to 15NO3 in all outputs. Consistent low 15N2O levels were present in P&S, with increasing levels of N2 peaking 48h after 15NH4 injection, suggesting denitrification dominated N removal. By contrast, SND and GEO 15N2O levels rose quickly, peaking 8h after 15NH4 injection, suggesting N loss by nitrification. When the whole system is considered, including sand filter removal, 26 - 27% of total N was removed by the SND and GEO systems, whereas 14% of total N was removed in the P&S system. Our results suggest the SND and GEO systems as a whole are capable of removing a greater mass of N than the P&S system.

  19. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 9, Removal action system design

    SciTech Connect

    Not Available

    1992-04-01

    This Removal Action System Design has been prepared as a Phase I Volume for the implementation of the Phase II removal action at Wright-Patterson Air Force Base (WPAFB) near Dayton, Ohio. The objective of the removal action is to prevent, to the extent practicable, the migration of ground water contaminated with chlorinated volatile organic compounds (VOCS) across the southwest boundary of Area C. The Phase 1, Volume 9 Removal Action System Design compiles the design documents prepared for the Phase II Removal Action. These documents, which are presented in Appendices to Volume 9, include: Process Design, which presents the 30 percent design for the ground water treatment system (GWTS); Design Packages 1 and 2 for Earthwork and Road Construction, and the Discharge Pipeline, respectively; no drawings are included in the appendix; Design Package 3 for installation of the Ground Water Extraction Well(s); Design Package 4 for installation of the Monitoring Well Instrumentation; and Design Package 5 for installation of the Ground Water Treatment System; this Design Package is incorporated by reference because of its size.

  20. Virtual wall-based haptic-guided teleoperated surgical robotic system for single-port brain tumor removal surgery.

    PubMed

    Seung, Sungmin; Choi, Hongseok; Jang, Jongseong; Kim, Young Soo; Park, Jong-Oh; Park, Sukho; Ko, Seong Young

    2017-01-01

    This article presents a haptic-guided teleoperation for a tumor removal surgical robotic system, so-called a SIROMAN system. The system was developed in our previous work to make it possible to access tumor tissue, even those that seat deeply inside the brain, and to remove the tissue with full maneuverability. For a safe and accurate operation to remove only tumor tissue completely while minimizing damage to the normal tissue, a virtual wall-based haptic guidance together with a medical image-guided control is proposed and developed. The virtual wall is extracted from preoperative medical images, and the robot is controlled to restrict its motion within the virtual wall using haptic feedback. Coordinate transformation between sub-systems, a collision detection algorithm, and a haptic-guided teleoperation using a virtual wall are described in the context of using SIROMAN. A series of experiments using a simplified virtual wall are performed to evaluate the performance of virtual wall-based haptic-guided teleoperation. With haptic guidance, the accuracy of the robotic manipulator's trajectory is improved by 57% compared to one without. The tissue removal performance is also improved by 21% ( p < 0.05). The experiments show that virtual wall-based haptic guidance provides safer and more accurate tissue removal for single-port brain surgery.

  1. Study on nitrogen removal enhanced by shunt distributing wastewater in a constructed subsurface infiltration system under intermittent operation mode.

    PubMed

    Li, Yinghua; Li, Haibo; Sun, Tieheng; Wang, Xin

    2011-05-15

    Subsurface wastewater infiltration system is an efficient and economic technology in treating small scattered sewage. The removal rates are generally satisfactory in terms of COD, BOD(5), TP and SS removal; while nitrogen removal is deficient in most of the present operating SWIS due to the different requirements for the presence of oxygen for nitrification and denitrification processes. To study the enhanced nitrogen removal technologies, two pilot subsurface wastewater infiltration systems were constructed in a village in Shenyang, China. The filled matrix was a mixture of 5% activated sludge, 65% brown soil and 30% coal slag in volume ratio for both systems. Intermittent operation mode was applied in to supply sufficient oxygen to accomplish the nitrification; meanwhile sewage was supplemented as the carbon source to the lower part in to denitrify. The constructed subsurface wastewater infiltration systems worked successfully under wetting-drying ratio of 1:1 with hydraulic loading of 0.081 m(3)/(m(2)d) for over 4 months. Carbon source was supplemented with shunt ratio of 1:1 and shunt position at the depth of 0.5m. The experimental results showed that intermittent operation mode and carbon source supplementation could significantly enhance the nitrogen removal efficiency with little influence on COD and TP removal. The average removal efficiencies for NH(3)-N and TN were 87.7 ± 1.4 and 70.1 ± 1.0%, increased by 12.5 ± 1.0 and 8.6 ± 0.7%, respectively.

  2. Long term operation of continuous-flow system with enhanced biological phosphorus removal granules at different COD loading.

    PubMed

    Li, Dong; Lv, Yufeng; Zeng, Huiping; Zhang, Jie

    2016-09-01

    In this study, a continuous-flow system with enhanced biological phosphorus removal (EBPR) granules was operated at different COD concentrations (200, 300 and 400mgL(-)(1)) to investigate the effect of COD loading on this system. The results showed that when the COD concentration in influent was increased to 400mgL(-)(1), the anaerobic COD removal efficiency and total phosphorus removal efficiency reduced obviously and the settling ability of granules deteriorated due to the proliferation of filamentous bacteria. Moreover, high COD loading inhibited the EPS secretion and destroyed the stability of granules. Results of high-through pyrosequencing indicated that filamentous bacteria had a competitive advantage over polyphosphate-accumulating organisms (PAOs) at high COD loading. The performance of system, settling ability of granules and proportion of PAOs gradually recovered to the initial level after the COD concentration was reduced to 200mgL(-)(1) on day 81.

  3. Electron Affinity Calculations for Thioethers

    NASA Technical Reports Server (NTRS)

    Sulton, Deley L.; Boothe, Michael; Ball, David W.; Morales, Wilfredo

    1997-01-01

    Previous work indicated that polyphenyl thioethers possessed chemical properties, related to their electron affinities, which could allow them to function as vapor phase lubricants (VPL). Indeed, preliminary tribological tests revealed that the thioethers could function as vapor phase lubricants but not over a wide temperature and hertzian pressure range. Increasing the electron affinity of the thioethers may improve their VPL properties over this range. Adding a substituent group to the thioether will alter its electron affinity in many cases. Molecular orbital calculations were undertaken to determine the effect of five different substituent groups on the electron affinity of polyphenyl thioethers. It was found that the NO2, F, and I groups increased the thioethers electron affinity by the greatest amount. Future work will involve the addition of these groups to the thioethers followed by tribological testing to assess their VPL properties.

  4. Systemic effects of geoengineering by terrestrial carbon dioxide removal on carbon related planetary boundaries

    NASA Astrophysics Data System (ADS)

    Heck, Vera; Donges, Jonathan; Lucht, Wolfgang

    2015-04-01

    The planetary boundaries framework as proposed by Rockström et al. (2009) provides guidelines for ecological boundaries, the transgression of which is likely to result in a shift of Earth system functioning away from the relatively stable Holocene state. As the climate change boundary is already close to be transgressed, several geoengineering (GE) methods are discussed, aiming at a reduction of atmospheric carbon concentrations to control the Earth's energy balance. One of the proposed GE methods is carbon extraction from the atmosphere via biological carbon sequestration. In case mitigation efforts fail to substantially reduce greenhouse gas emissions, this form of GE could act as potential measure to reduce atmospheric carbon dioxide concentrations. We here study the possible influences of human interactions in the Earth system on carbon related planetary boundaries in the form of geoengineering (terrestrial carbon dioxide removal). We use a conceptual model specifically designed to investigate fundamental carbon feedbacks between land, ocean and atmosphere (Anderies et al., 2013) and modify it to include an additional geoengineering component. With that we analyze the existence and stability of a safe operating space for humanity, which is here conceptualized in three of the 9 proposed dimensions, namely climate change, ocean acidification and land-use. References: J. M. Anderies et al., The topology of non-linear global carbon dynamics: from tipping points to planetary boundaries. Environ. Res. Lett., 8(4):044048 (2013) J. Rockström et al., A safe operating space for humanity. Nature 461 (7263), 472-475 (2009)

  5. Monitoring intracellular polyphosphate accumulation in enhanced biological phosphorus removal systems by quantitative image analysis.

    PubMed

    Mesquita, Daniela P; Amaral, A Luís; Leal, Cristiano; Carvalheira, Mónica; Cunha, Jorge R; Oehmen, Adrian; Reis, Maria A M; Ferreira, Eugénio C

    2014-01-01

    A rapid methodology for intracellular storage polyphosphate (poly-P) identification and monitoring in enhanced biological phosphorus removal (EBPR) systems is proposed based on quantitative image analysis (QIA). In EBPR systems, 4',6-diamidino-2-phenylindole (DAPI) is usually combined with fluorescence in situ hybridization to evaluate the microbial community. The proposed monitoring technique is based on a QIA procedure specifically developed for determining poly-P inclusions within a biomass suspension using solely DAPI by epifluorescence microscopy. Due to contradictory literature regarding DAPI concentrations used for poly-P detection, the present work assessed the optimal DAPI concentration for samples acquired at the end of the EBPR aerobic stage when the accumulation occurred. Digital images were then acquired and processed by means of image processing and analysis. A correlation was found between average poly-P intensity values and the analytical determination. The proposed methodology can be seen as a promising alternative procedure for quantifying intracellular poly-P accumulation in a faster and less labour-intensive way.

  6. Carbon dioxide removal system for closed loop atmosphere revitalization, candidate sorbents screening and test results

    NASA Astrophysics Data System (ADS)

    Mattox, E. M.; Knox, J. C.; Bardot, D. M.

    2013-05-01

    Due to the difficulty and expense it costs to resupply manned-spacecraft habitats, a goal is to create a closed loop atmosphere revitalization system, in which precious commodities such as oxygen, carbon dioxide, and water are continuously recycled. Our aim is to test other sorbents for their capacity for future spacecraft missions, such as on the Orion spacecraft, or possibly lunar or Mars mission habitats to see if they would be better than the zeolite sorbents on the 4-bed molecular sieve. Some of the materials being tested are currently used for other industry applications. Studying these sorbents for their specific spacecraft application is different from that for applications on earth because in space, there are certain power, mass, and volume limitations that are not as critical on Earth. In manned-spaceflight missions, the sorbents are exposed to a much lower volume fraction of CO2 (0.6% volume CO2) than on Earth. LiLSX was tested for its CO2 capacity in an atmosphere like that of the ISS. Breakthrough tests were run to establish the capacities of these materials at a partial pressure of CO2 that is seen on the ISS. This paper discusses experimental results from benchmark materials, such as results previously obtained from tests on Grade 522, and the forementioned candidate materials for the Carbon Dioxide Removal Assembly (CDRA) system.

  7. Thermophysiological responses induced by a body heat removal system with Peltier devices in a hot environment.

    PubMed

    Suzurikawa, Jun; Fujimoto, Sho; Mikami, Kousei; Jonai, Hiroshi; Inoue, Takenobu

    2013-01-01

    Individuals with spinal cord injuries often experience thermoregulation disorders as well as sensory and motor disabilities. In order to prevent such individuals from becoming hyperthermic, we developed a body heat removal system (BHRS) with thermoelectric devices. Our BHRS comprises four Peltier devices mounted on a wheelchair backrest and continuously transfers body heat through the contacting interface to the external environment. Here, we characterized thermophysiological responses induced by this novel contact-type cooling system. A cooling experiment in a hot environment with five able-bodied subjects demonstrated that sweating and systolic blood pressure in the back-cooling (BC) trial were significantly suppressed compared with those in no-cooling (NC) trial, while no difference was found in oral and skin temperatures. A correlation was observed between chest skin temperature and blood flow in the NC trial; this was not observed in the BC trial. These results suggest that BHRS modulates normal thermoregulatory responses, including sweating and vascular dilation and has the capability to partly replace these functions.

  8. Effect of IDA and TREN chelating agents and buffer systems on the purification of human IgG with immobilized nickel affinity membranes.

    PubMed

    Ribeiro, Mariana Borsoi; Vijayalakshmi, Mookambesvaran; Todorova-Balvay, Daniele; Bueno, Sonia Maria Alves

    2008-01-01

    The purification of IgG from human plasma was studied by comparing two affinity membranes complexed with Ni(II), prepared by coupling iminodiacetic acid (IDA) and Tris(2-aminoethyl)amine (TREN) to poly(ethylenevinyl alcohol), PEVA, hollow fiber membranes. The Ni(II)-TREN-PEVA hollow fiber membrane had lower capacity for human IgG than the complex Ni(II)-IDA-PEVA, but with similar selectivity. The IgG in peak fractions eluted from the Ni(II)-IDA-PEVA with a stepwise concentration gradient of Tris-HCl pH 7.0 (100-700 mM) reached a purity of 98% (based on IgG, IgM, IgA, albumin, and transferrin nephelometric analysis). Adsorption IgG data at different temperatures (4-37 degrees C) were analyzed using Langmuir model resulting in a calculated maximum capacity at 25 degrees C of 204.6 mg of IgG/g of dry membrane. Decrease in Kd with increasing temperature (1.7x10(-5) to 5.3x10(-6) M) indicated an increase in affinity with increased temperature. The positive value of enthalpy change (26.2 kJ/mol) indicated that the adsorption of IgG in affinity membrane is endothermic. Therefore, lower temperature induces adsorption as verified experimentally.

  9. The electron affinity of gallium nitride (GaN) and digallium nitride (GaNGa): the importance of the basis set superposition error in strongly bound systems.

    PubMed

    Tzeli, Demeter; Tsekouras, Athanassios A

    2008-04-14

    The electron affinity of GaN and Ga2N as well as the geometries and the dissociation energies of the ground states of gallium nitrides GaN, GaN(-), Ga2N, and Ga2N(-) were systematically studied by employing the coupled cluster method, RCCSD(T), in conjunction with a series of basis sets, (aug-)cc-pVxZ(-PP), x=D, T, Q, and 5 and cc-pwCVxZ(-PP), x=D, T, and Q. The calculated dissociation energy and the electron affinity of GaN are 2.12 and 1.84 eV, respectively, and those of Ga2N are 6.31 and 2.53 eV. The last value is in excellent agreement with a recent experimental value for the electron affinity of Ga2N of 2.506+/-0.008 eV. For such quality in the results to be achieved, the Ga 3d electrons had to be included in the correlation space. Moreover, when a basis set is used, which has not been developed for the number of the electrons which are correlated in a calculation, the quantities calculated need to be corrected for the basis set superposition error.

  10. Performance of the active sidewall boundary-layer removal system for the Langley 0.3-meter Transonic Cryogenic Tunnel

    NASA Technical Reports Server (NTRS)

    Balakrishna, S.; Kilgore, W. Allen; Murthy, A. V.

    1989-01-01

    A performance evaluation of an active sidewall boundary-layer removal system for the Langley 0.3-m Transonic Cryogenic Tunnel (TCT) was evaluated in 1988. This system uses a compressor and two throttling digital valves to control the boundary-layer mass flow removal from the tunnel. The compressor operates near the maximum pressure ratio for all conditions. The system uses a surge prevention and flow recirculation scheme. A microprocessor based controller is used to provide the necessary mass flow and compressor pressure ratio control. Initial tests on the system indicated problems in realizing smooth mass flow control while running the compressor at high speed and high pressure ratios. An alternate method has been conceived to realize boundary-layer mass flow control which avoids the recirculation of the compressor mass flow and operation near the compressor surge point. This scheme is based on varying the speed of the compressor for a sufficient pressure ratio to provide needed mass flow removal. The system has a mass flow removal capability of about 10 percent of test section flow at M = 0.3 and 4 percent at M = 0.8. The system performance has been evaluated in the form of the compressor map, and compressor tunnel interface characteristics covering most of the 0.3-m TCT operational envelope.

  11. Test report for K Basin MK I lid removal and replacement system

    SciTech Connect

    Omberg, R.P.; Roe, N.R.

    1996-08-21

    This report provides the results of acceptance testing of sampling equipment for use in the Hanford K Basin. The equipment, MK I Lid Removal/Replacement Tools, were designed to remove/replace MK I Spent Fuel Canister lids so that other equipment may be used to sample the canister contents. The tools were determined to be acceptable for their intended use.

  12. EVALUATING SURROGATES FOR CRYPTOSPORIDIUM REMOVAL IN POINT-OF-USE SYSTEMS

    EPA Science Inventory

    Cryptosporidium oocysts are resistant to chlorination and are particularly difficult to remove from drinking water by filtration due to their small size (4 µm to 6 µm). Filters with nominal pore sizes of 1 µm are recommended to assure effective removals. Properly designed and o...

  13. Removal of Heavy Metals from Aqueous Systems with Thiol Functionalized Superparamagnetic Nanoparticles

    SciTech Connect

    Yantasee, Wassana; Warner, Cynthia L.; Sangvanich, Thanapon; Addleman, Raymond S.; Carter, Timothy G.; Wiacek, Robert J.; Fryxell, Glen E.; Timchalk, Chuck; Warner, Marvin G.

    2007-06-09

    We have shown that superparamagnetic iron oxide (Fe3O4) nanoparticles with a surface functionalization of dimercaptosuccinic acid is an effective, magnetic, sorbent material for toxic metals such as Hg, Ag, Pb, Cd and other soft cations. The chemical affinity, stability, capacity and kinetics of the functionalized nanoparticles has been explored and compared to conventional resin based sorbents and nanoporous silica materials with similar surface chemistries.

  14. pH-dependent ammonia removal pathways in microbial fuel cell system.

    PubMed

    Kim, Taeyoung; An, Junyeong; Lee, Hyeryeong; Jang, Jae Kyung; Chang, In Seop

    2016-09-01

    In this work, ammonia removal paths in microbial fuel cells (MFCs) under different initial pH conditions (pH 7.0, 8.0, and 8.6) were investigated. At a neutral pH condition (pH 7.0), MFC used an electrical energy of 27.4% and removed 23.3% of total ammonia by electrochemical pathway for 192h. At the identical pH condition, 36.1% of the total ammonia was also removed by the biological path suspected to be biological ammonia oxidation process (e.g., Anammox). With the initial pH increased, the electrochemical removal efficiency decreased to less than 5.0%, while the biological removal efficiency highly increased to 61.8%. In this study, a neutral pH should be maintained in the anode to utilize MFCs for ammonia recovery via electrochemical pathways from wastewater stream.

  15. Method and apparatus for removing non-condensible gas from a working fluid in a binary power system

    DOEpatents

    Mohr, Charles M.; Mines, Gregory L.; Bloomfield, K. Kit

    2002-01-01

    Apparatus for removing non-condensible gas from a working fluid utilized in a thermodynamic system comprises a membrane having an upstream side operatively connected to the thermodynamic system so that the upstream side of the membrane receives a portion of the working fluid. The first membrane separates the non-condensible gas from the working fluid. A pump operatively associated with the membrane causes the portion of the working fluid to contact the membrane and to be returned to the thermodynamic system.

  16. Autotrophic nitrogen removal from domestic sewage in MBR-CANON system and the biodiversity of functional microbes.

    PubMed

    Zhang, Xiaojing; Li, Dong; Liang, Yuhai; He, Yongping; Zhang, Yulong; Zhang, Jie

    2013-12-01

    The feasibility of completely autotrophic nitrogen removal over nitrite (CANON) process for treating domestic sewage was investigated in membrane bioreactor (MBR), for which conventional activated sludge was seeded at ambient temperature. By gradually decreasing hydraulic retention time under the oxygen-limited condition, CANON was successfully started-up for 78 days. Finally the MBR-CANON system was adopted for treating domestic sewage, nitrogen and COD removal achieved to 0.97 kg m(-3) d(-1), 80%, respectively, with the effluent turbidity below 1.0 NTU. DGGE profiles showed a distinct community shift of the functional bacteria after seeded to the reactor, and phylogenetic results indicated the predominance of Nitrosomonas and Candidatus Kuenenia stuttgartiensis for nitrogen removal in the reactor. FISH results showed the predominance of aerobic ammonia oxidizing bacteria (AerAOB) and anaerobic ammonia oxidizing bacteria (AnAOB) in the system, both of whose proportion reduced when treated domestic sewage.

  17. Effects of floc aluminum on activated sludge characteristics and removal of 17-alpha-ethinylestradiol in wastewater systems.

    PubMed

    Park, Chul; Fang, Yuan; Murthy, Sudhir N; Novak, John T

    2010-03-01

    The effects of floc aluminum (Al) on activated sludge performance and 17-alpha-ethinylestradiol (EE2) removal were studied using bench-scale activated sludge systems. The results showed that higher Al-fed activated sludge led to better settling, dewatering, and effluent quality with better EE2 removal. EE2 concentrations in the effluent revealed correlations with effluent suspended solids and large particulate/colloidal effluent biopolymer (protein+polysaccharide). Furthermore, a significant correlation existed between effluent proteins and EE2 for all size fractions, indicating that hydrophobic proteinaceous colloids provide binding sites for EE2 and washout together into the effluent. These results suggest that aluminum plays a crucial role in bioflocculation of activated sludge and the efficacy of flocculation influences the removal of endocrine disrupting compounds (EDCs) from wastewater treatment systems.

  18. Removal of ethylene and bioaerosol by chlorine dioxide using a chemical scrubbing system in a fruit and vegetable storage facility.

    PubMed

    Chang, Tsu-Hua; Wu, Li-Chun; You, Ya-Ting; Chung, Ying-Chien

    2009-02-15

    Ethylene (C2H4) and bioaerosol are commonly present in the inside atmosphere of postharvest fruit and vegetable storage facilities, which may affect the aging of postharvest fruit and human health. We have assessed the feasibility of chlorine dioxide (ClO2) as the scrubbing solution in a chemical scrubbing tower for simultaneously removing C2H4 and bioaerosol emissions from a gas stream. Parameters such as the ClO2concentration, contact time, and liquid-to-gas (L/G) ratio were examined with the aim of determining the optimal operating conditions. Using the system reported here, the optimal C2H4 removal efficiency was 99.5% when 500 ppm ClO2 was used at a reaction time of 30-60 s under a continuous non-recycle ClO2 flow mode. In terms of C2H4 removal, a greater L/G resulted in a higher C2H4 removal efficiency up to the optimal ratio of 12.5. In terms of the simultaneous removal of C2H4 and bioaerosol, the removal efficiency of C2H4 was 99.2% and those for the bioaersols of Escherichia coli and Staphylococcus aureus were 99.92 and 99.10%, respectively, under a continuous non-recycle flow mode. Our results also indicate that oxidation reduction potential (ORP) can be a valuable indicator for the timing of the replacement of the scrubbing solution in the system under a continuous recycle flow mode. Additional confirmation of the feasibility of the ORP as an indicator of C2H4 and bioaerosol removal in situ was obtained in a 3-month test of our system in continuous recycle flow mode with the periodical replacement of scrubbing solution, ClO2. The removal efficiencies for C2H4, bacterial and fungus aerosol, and total hydrocarbon compounds (THC) were 83.4, 96.8, 96.1, and 76.5%, respectively. Our results prove that ClO2 is an excellent scrubbing solution in the chemical scrubbing tower for the removal of C2H4 emissions and bioaerosol. We demonstrate, for the first time, the feasibility of this system in a fruit and vegetable storage facility.

  19. Coupling of a bioelectrochemical system for p-nitrophenol removal in an upflow anaerobic sludge blanket reactor.

    PubMed

    Shen, Jinyou; Xu, Xiaopeng; Jiang, Xinbai; Hua, Congxin; Zhang, Libin; Sun, Xiuyun; Li, Jiansheng; Mu, Yang; Wang, Lianjun

    2014-12-15

    Coupling of a bioelectrochemical system (BES) into the upflow anaerobic sludge blanket (UASB) was developed for enhanced p-nitrophenol (PNP) removal in this study. Compared to the control UASB reactor, both PNP removal and the formation of its final reductive product p-aminophenol (PAP) were notably improved in the UASB-BES system. With the increase of current density from 0 to 4.71 A m(-3), the rates of PNP removal and PAP formation increased from 6.16 ± 0.11 and 4.21 ± 0.29 to 6.77 ± 0.00 and 6.11 ± 0.28 mol m(-3) d(-1), respectively. More importantly, the required dosage of organic cosubstrate was significantly reduced in the UASB-BES system than that in the UASB reactor. Organic carbon flux analysis suggested that biogas production from organic cosubstrate was seriously suppressed while direct anaerobic reduction of PNP was not remarkably affected by current input in the UASB-BES system. This study demonstrated that the UASB-BES coupling system had a promising potential for the removal of nitrophenol-containing wastewaters especially without adequate organic cosubstrates inside.

  20. Optimization of Biosorptive Removal of Dye from Aqueous System by Cone Shell of Calabrian Pine

    PubMed Central

    Deniz, Fatih

    2014-01-01

    The biosorption performance of raw cone shell of Calabrian pine for C.I. Basic Red 46 as a model azo dye from aqueous system was optimized using Taguchi experimental design methodology. L9 (33) orthogonal array was used to optimize the dye biosorption by the pine cone shell. The selected factors and their levels were biosorbent particle size, dye concentration, and contact time. The predicted dye biosorption capacity for the pine cone shell from Taguchi design was obtained as 71.770 mg g−1 under optimized biosorption conditions. This experimental design provided reasonable predictive performance of dye biosorption by the biosorbent (R 2: 0.9961). Langmuir model fitted better to the biosorption equilibrium data than Freundlich model. This displayed the monolayer coverage of dye molecules on the biosorbent surface. Dubinin-Radushkevich model and the standard Gibbs free energy change proposed physical biosorption for predominant mechanism. The logistic function presented the best fit to the data of biosorption kinetics. The kinetic parameters reflecting biosorption performance were also evaluated. The optimization study revealed that the pine cone shell can be an effective and economically feasible biosorbent for the removal of dye. PMID:25405213

  1. Optimization of biosorptive removal of dye from aqueous system by cone shell of Calabrian pine.

    PubMed

    Deniz, Fatih

    2014-01-01

    The biosorption performance of raw cone shell of Calabrian pine for C.I. Basic Red 46 as a model azo dye from aqueous system was optimized using Taguchi experimental design methodology. L9 (3(3)) orthogonal array was used to optimize the dye biosorption by the pine cone shell. The selected factors and their levels were biosorbent particle size, dye concentration, and contact time. The predicted dye biosorption capacity for the pine cone shell from Taguchi design was obtained as 71.770 mg g(-1) under optimized biosorption conditions. This experimental design provided reasonable predictive performance of dye biosorption by the biosorbent (R (2): 0.9961). Langmuir model fitted better to the biosorption equilibrium data than Freundlich model. This displayed the monolayer coverage of dye molecules on the biosorbent surface. Dubinin-Radushkevich model and the standard Gibbs free energy change proposed physical biosorption for predominant mechanism. The logistic function presented the best fit to the data of biosorption kinetics. The kinetic parameters reflecting biosorption performance were also evaluated. The optimization study revealed that the pine cone shell can be an effective and economically feasible biosorbent for the removal of dye.

  2. Study of solar photo-Fenton system applied to removal of phenol from water.

    PubMed

    Freire, Layla F A; da Fonseca, Fabiana Valéria; Yokoyama, Lidia; Teixeira, Luiz Alberto Cesar

    2014-01-01

    This study evaluated the use of a Fenton's reaction in a falling film solar reactor (FFR), as a possible advanced oxidation process for the mineralization of the organic compound phenol in water. Preliminary tests were carried out to evaluate phenol degradation by photolysis and to select the optimal residence time in which to carry out the process using a solar photo-Fenton system. The variables studied were the initial phenol concentration (100 to 300 mg L(-1)), the [Phenol]:[H2O2] mass ratio (1.0 to 2.0) and the [H2O2]/[Fe2+] molar ratio (5 to 10). Phenol degradation of 99% and chemical oxygen demand (COD) reduction of 97% were obtained under the following reaction conditions: phenol concentration=200 mg L(-1), mass ratio [Phenol]:[H2O2]=1.5 and molar ratio [H2O2]/[Fe2+]=7.5. Overall mineralization was achieved using the solar photo-Fenton process to destroy phenol and COD. The solar photo-Fenton process using a FFR appears to be a viable method for removing phenols in wastewaters on an industrial scale.

  3. Thermalhydraulic aspects of decay heat removal by natural circulation in fast reactor systems

    SciTech Connect

    Roy, C.M.; Hetsroni, G.; Banerjee, S.

    1990-01-01

    Natural convection in enclosures have been studied numerically to provide insight into the scaling laws existing for removal of decay heat in Liquid Metal Fast Reactors (LMFR). Specifically, 3-D simulations have been carried out for natural circulation in a cylinder with small aspect ratio (of the order of 0.5). These results have been compared to the results of an experiment conducted by UCSB, in collaboration with GE, to provide benchmark data for code validation. Parametric studies have been conducted to establish the validity of a 3-D Finite difference code that uses body-fitted grids for simulations of complex geometries. Further, numerical simulations have been carried out to demonstrate the importance of 3-D computer codes as tools in the design and scale-up of prototype LMFRs. It has been shown that the geometry of the passive safety systems is key to safe operation of LMFRs under shutdown conditions. The key phenomena that occur in such situations have bee studied and the available experimental studies have been identified. The future direction for modeling of natural convection recirculating flows in confined enclosures has been proposed. 31 refs.

  4. Thermalhydraulic aspects of decay heat removal by natural circulation in fast reactor systems. Final report

    SciTech Connect

    Roy, C.M.; Hetsroni, G.; Banerjee, S.

    1990-12-31

    Natural convection in enclosures have been studied numerically to provide insight into the scaling laws existing for removal of decay heat in Liquid Metal Fast Reactors (LMFR). Specifically, 3-D simulations have been carried out for natural circulation in a cylinder with small aspect ratio (of the order of 0.5). These results have been compared to the results of an experiment conducted by UCSB, in collaboration with GE, to provide benchmark data for code validation. Parametric studies have been conducted to establish the validity of a 3-D Finite difference code that uses body-fitted grids for simulations of complex geometries. Further, numerical simulations have been carried out to demonstrate the importance of 3-D computer codes as tools in the design and scale-up of prototype LMFRs. It has been shown that the geometry of the passive safety systems is key to safe operation of LMFRs under shutdown conditions. The key phenomena that occur in such situations have bee studied and the available experimental studies have been identified. The future direction for modeling of natural convection recirculating flows in confined enclosures has been proposed. 31 refs.

  5. Efficiency of bioaugmentation in the removal of organic matter in aquaculture systems.

    PubMed

    Lopes, R B; Olinda, R A; Souza, B A I; Cyrino, J E P; Dias, C T S; Queiroz, J F; Tavares, L H S

    2011-05-01

    Several techniques are currently used to treat effluents. Bioaugmentation is a new bioremediation strategy and has been employed to improve effluent quality by treating the water during the production process. This technology consists basically of the addition of microorganisms able to degrade or remove polluting compounds, especially organic matter and nutrients. The objective of this study was to assess the effects of bioaugmentation on some parameters of organic matter and on the performance of juvenile tilapias in an intensive aquaculture production system. The combination of two bacterial consortiums in a complete randomized design was employed in a factorial analysis with two factors. Statistical differences between treatments were analyzed by the analysis of variance (ANOVA) and Tukey test at the 5% level. One of the treatments, heterotrophic bacterial supplementation, was able to reduce biochemical oxygen demand (BOD) by 23%, dissolved organic carbon (DOC) by 83.7% and phytoplanktonic biomass by 43%. On the other hand, no damage was done to either the physical-chemical indicators of water quality or to the growth performance of juvenile tilapias assessed in this study.

  6. Initial Field Deployment Results of Green PCB Removal from Sediment Systems (GPRSS)

    NASA Technical Reports Server (NTRS)

    DeVor, Robert William

    2014-01-01

    The goal of this task order was to complete optimization and development of the Green PCB Remediation from Sediment Systems(GPRSSs) technology, culminating in the production of functioning demonstration test units which would be deployed at a suitable demonstration location. This location would be selected in conjunction with Toxicological & Ecological Associates who have entered into a SAA with NASA to partner with and further develop this technology. The GPRSSs technology was initially developed under ESC Task Order 83 with the purpose of providing a green remediation technology capable of in-situ removal and remediation of polychlorinated biphenyls (PCBs) from contaminated sediments. The core concept of the technology, a polymeric blanket capable of absorbing PCBs when in contact with contaminated sediments was then transitioned to Task Order 165 where the primary objective was to fully design and optimize a functioning test unit capable of testing the theoretical and laboratory scale concepts in a real world situation. Results from both task orders are included in this report for completeness, although Task Order 165 focused on the blanket design and the small scale field demonstration in which is currently still ongoing in Altavista, VA.

  7. Functionalized Nanoporous Silica for Removal of Heavy Metals from Biological Systems; Adsorption and Application

    SciTech Connect

    Yantasee, Wassana; Rutledge, Ryan D.; Chouyyok, Wilaiwan; Sukwarotwat, Vichaya; Orr, Galya; Warner, Cynthia L.; Warner, Marvin G.; Fryxell, Glen E.; Wiacek, Robert J.; Timchalk, Charles; Addleman, Raymond S.

    2010-10-01

    Functionalized nanoporous silica, often referred to as self-assembled monolayers on mesoporous supports (SAMMS) have previously demonstrated the ability to serve as very effective heavy metal sorbents in a range of aquatic and environmental systems suggesting they may be advantageously utilized for biomedical applications such as chelation therapy. Herein we evaluate surface chemistries for heavy metal capture from biological fluids, various facets of the materials biocompatibility and the suitability of these materials as potential therapeutics. Of the materials tested, thiol-functionalized SAMMS proved most capable of removing selected heavy metals from biological solutions (i.e. blood, urine, etc.) As a result, thiol SAMMS was further analyzed to assess the material’s performance under a number of different biologically relevant conditions (i.e. variable pH and ionic strength) as well to gauge any potentially negative cellular effects resulting from interaction with the sorbent, such as cellular toxicity or possible chelation of essential minerals. Additionally, cellular uptake studies demonstrated no cell membrane permeation by the silica-based materials generally highlighting their ability to remain cellularly inert and thus non-toxic. As a result, it has been determined that organic ligand-functionalized nanoporous silica materials could be a valuable material for detoxification therapeutics and potentially other biomedical applications as needed.

  8. Nitrate removal from polluted water by using a vegetated floating system.

    PubMed

    Bartucca, Maria Luce; Mimmo, Tanja; Cesco, Stefano; Del Buono, Daniele

    2016-01-15

    Nitrate (NO3(-)) water pollution is one of the most prevailing and relevant ecological issues. For instance, the wide presence of this pollutant in the environment is dramatically altering the quality of superficial and underground waters. Therefore, we set up a floating bed vegetated with a terrestrial herbaceous species (Italian ryegrass) with the aim to remediate hydroponic solutions polluted with NO3(-). The floating bed allowed the plants to grow and achieve an adequate development. Ryegrass was not affected by the treatments. On the contrary, plant biomass production and total nitrogen content (N-K) increased proportionally to the amount of NO3(-) applied. Regarding to the water cleaning experiments, the vegetated floating beds permitted to remove almost completely all the NO3(-) added from the hydroponic solutions with an initial concentration of 50, 100 and 150 mg L(-1). Furthermore, the calculation of the bioconcentration factor (BCF) indicated this species as successfully applicable for the remediation of solutions polluted by NO3(-). In conclusion, the results highlight that the combination of ryegrass and the floating bed system resulted to be effective in the remediation of aqueous solutions polluted by NO3(-).

  9. Understanding the role of extracellular polymeric substances in an enhanced biological phosphorus removal granular sludge system.

    PubMed

    Wang, Randeng; Peng, Yongzhen; Cheng, Zhanli; Ren, Nanqi

    2014-10-01

    The role of extracellular polymeric substances (EPS) in the enhanced biological phosphorus removal (EBPR) process was investigated in a P-accumulating granular sludge system by analyzing the distribution and transfer of P, K(+), Mg(2+) and Ca(2+) in the sludge phase, EPS, and the bulk liquid. In the sludge phase, about 30% P, 44.7% K(+), 27.7% Mg(2+), 28% Ca(2+) accumulated in the EPS at the end of aeration. The rate of P, K(+), Mg(2+) and Ca(2+) released from the EPS matrix into the bulk liquid in the anaerobic phase was faster than the rate they were adsorbed from the bulk liquid into the EPS in the aerobic phase. P, K(+), Mg(2+) and Ca(2+) were retained in EPS before transferring into the phosphorus accumulating organisms (PAOs). These results suggest that EPS play a critical role in facilitating the accumulation and transfer of P, K(+), Ca(2+) and Mg(2+) between PAO cells and bulk liquid.

  10. Space Shuttle reaction control system thruster metal nitrate removal and characterization

    NASA Technical Reports Server (NTRS)

    Saulsberry, R. L.; Mccartney, P. A.

    1993-01-01

    The Space Shuttle hypergolic primary reaction control system (PRCS) thrusters continue to fail-leak or fail-off at a rate of approximately 1.5 per flight, attributed primarily to metal nitrate formation in the nitrogen tetroxide (N2O4) pilot operated valves (POV's). The failures have continued despite ground support equipment (GSE) and subsystem operational improvements. As a result, the Johnson Space Center (JSC) White Sands Test Facility (WSTF) performed a study to characterize the contamination in the N204 valves. This study prompted the development and implementation of a highly successful flushing technique using deionized (DI) water and gaseous nitrogen (GN2) to remove the contamination while minimizing Teflon seat damage. Following flushing a comprehensive acceptance test is performed before the thruster is deemed recovered. Between the time WSTF was certified to process flight thrusters (March 1992) and September 1993, a 68 percent thruster recovery rate was achieved. The contamination flushed from these thrusters was analyzed and has provided insight into the corrosion process, which is reported in this publication. Additionally, the long-term performance of 24 flushed thrusters installed in the WSTF Fleet Leader Shuttle reaction control subsystem (RCS) test articles is being assessed. WSTF continues to flush flight and test article thrusters and compile data to investigate metal nitrate formation characteristics in leaking and nonleaking valves.

  11. Removal of soft deposits from the distribution system improves the drinking water quality.

    PubMed

    Lehtola, Markku J; Nissinen, Tarja K; Miettinen, Ilkka T; Martikainen, Pertti J; Vartiainen, Terttu

    2004-02-01

    Deterioration in drinking water quality in distribution networks represents a problem in drinking water distribution. These can be an increase in microbial numbers, an elevated concentration of iron or increased turbidity, all of which affect taste, odor and color in the drinking water. We studied if pipe cleaning would improve the drinking water quality in pipelines. Cleaning was arranged by flushing the pipes with compressed air and water. The numbers of bacteria and the concentrations of iron and turbidity in drinking water were highest at 9 p.m., when the water consumption was highest. Soft deposits inside the pipeline were occasionally released to bulk water, increasing the concentrations of iron, bacteria, microbially available organic carbon and phosphorus in drinking water. The cleaning of the pipeline decreased the diurnal variation in drinking water quality. With respect to iron, only short-term positive effects were obtained. However, removing of the nutrient-rich soft deposits did decrease the microbial growth in the distribution system during summer when there were favorable warm temperatures for microbial growth. No Norwalk-like viruses or coliform bacteria were detected in the soft deposits, in contrast to the high numbers of heterotrophic bacteria.

  12. Comparison of hydraulics and particle removal efficiencies in a mixed cell raceway and Burrows pond rearing system

    USGS Publications Warehouse

    Moffitt, Christine M.

    2016-01-01

    We compared the hydrodynamics of replicate experimental mixed cell and replicate standard Burrows pond rearing systems at the Dworshak National Fish Hatchery, ID, in an effort to identify methods for improved solids removal. We measured and compared the hydraulic residence time, particle removal efficiency, and measures of velocity using several tools. Computational fluid dynamics was used first to characterize hydraulics in the proposed retrofit that included removal of the traditional Burrows pond dividing wall and establishment of four counter rotating cells with appropriate drains and inlet water jets. Hydraulic residence time was subsequently established in the four full scale test tanks using measures of conductivity of a salt tracer introduced into the systems both with and without fish present. Vertical and horizontal velocities were also measured with acoustic Doppler velocimetry in transects across each of the rearing systems. Finally, we introduced ABS sinking beads that simulated fish solids then followed the kinetics of their removal via the drains to establish relative purge rates. The mixed cell raceway provided higher mean velocities and a more uniform velocity distribution than did the Burrows pond. Vectors revealed well-defined, counter-rotating cells in the mixed cell raceway, and were likely contributing factors in achieving a relatively high particle removal efficiency-88.6% versus 8.0% during the test period. We speculate retrofits of rearing ponds to mixed cell systems will improve both the rearing environments for the fish and solids removal, improving the efficiency and bio-security of fish culture. We recommend further testing in hatchery production trials to evaluate fish physiology and growth.

  13. Field Testing of a Prototype Filter System for the Removal of the Human Pathogen Giardia intestinales from Ground Water

    NASA Astrophysics Data System (ADS)

    Rust, C.; Schulze-Makuch, D.; Bowman, R.; Meier, D.

    2005-12-01

    Pathogenic bacteria, viruses, and protozoans tend to be negatively charged in the pH range of most ground waters. Thus, naturally occurring and modified materials such as surfactant-modified zeolites (SMZ), which have net positive surface charges and hydrophobic properties, are suitable as barriers to impede pathogen migration in aquifer systems. In our experiments SMZ has been used to remove E. coli and the bacteriophage MS-2 from sewage water with a high success rate ( E. coli 100%, MS-2 > 90%). Testing was conducted both in the laboratory and the field. Laboratory experiments were conducted to test the removal efficiency of SMZ for Giardia intestinales using the Giardia cysts and microsphere analogs. The SMZ was effective at removing Giardia intestinales cysts from the groundwater, but removal rates were not as high as for bacteria and viruses in the earlier experiments. The removal efficiency varied with the particular formulation of the SMZ used. The most effective SMZ formulation is being further tested at our field site using water amended with microspheres to simulate Giardia behavior. The field site is an existing multiple well site at the University of Idaho in Moscow. The wells are completed in the Lolo Basalt Formation; a highly heterogeneous and anisotropic fractured basalt aquifer system typical of the subsurface of most of eastern Washington and northeastern Oregon. The SMZ pathogen filter is installed directly in the well bore and the concentrations of microsphere-amended ground water are measured before and after filtration. Pumping over an extended period is continuing in order to test the lifetime of our prototype filter system. Our tests and results are targeted at developing a prototype filter system for removing a multitude of human pathogens in drinking water.

  14. Nitrogen removal from synthetic wastewater using single and mixed culture systems of denitrifying fungi, bacteria, and actinobacteria.

    PubMed

    Wang, Wenfeng; Cao, Lixiang; Tan, Hongming; Zhang, Renduo

    2016-11-01

    The aim of this study was to investigate the effects of single and mixed culture of denitrifying fungi, bacteria, and actinobacteria on nitrogen removal and N2O emission in treatment of wastewater. Denitrifying endophytes of Pseudomonas sp. B2, Streptomyces sp. A9, and Fusarium sp. F3 isolated from rice plants were utilized for treatment of synthetic wastewater containing nitrate and nitrite. Experiments were conducted under shaking and static conditions. Results showed that under the static condition, more than 97 % of nitrate removal efficiencies were reached in all the treatments containing B2. The nitrate removal rates within the first 12 h in the treatments of B2, B2+A9, B2+F3, and B2+A9+F3 were 7.3, 9.8, 11, and 11 mg L(-1) h(-1), respectively. Under the shaking condition, 100 % of nitrite was removed in all the treatments containing B2. The presence of A9 and F3 with B2 increased the nitrite removal rates under both the shaking and static conditions. Compared to the B2 system, the mixed systems of B2+A9, B2+F3, and B2+A9+F3 reduced N2O emission (78.4 vs. 19.4, 1.80, and 0.03 μM in 4 weeks, respectively). Our results suggested that B2 is an important strain that enhances nitrogen removal from wastewater. Mixed cultures of B2 with A9 and F3 can remove more nitrate and nitrite from wastewater and reduce nitrite accumulation and N2O emission in the denitrification process.

  15. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, PHYSICAL REMOVAL OF MICROBIAL CONTAMINATION AGENTS IN DRINKING WATER, ECOWATER SYSTEMS, INC., SEARS KENMORE ULTRAFILTER 500 DRINKING WATER TREATMENT SYSTEM (POU)

    EPA Science Inventory

    The Sears Kenmore Ultrafilter 500 RO system was tested for removal of bacteria and viruses at NSF International's Drinking Water Treatment Systems Laboratory. EcoWater Systems submitted ten units for testing, which were split into two groups of five. One group received 25 days ...

  16. Experimental and theoretical binding affinity between polyvinylpolypyrrolidone and selected phenolic compounds from food matrices.

    PubMed

    Durán-Lara, Esteban F; López-Cortés, Xaviera A; Castro, Ricardo I; Avila-Salas, Fabián; González-Nilo, Fernando D; Laurie, V Felipe; Santos, Leonardo S

    2015-02-01

    Polyvinylpolypyrrolidone (PVPP) is a fining agent, widely used in winemaking and brewing, whose mode of action in removing phenolic compounds has not been fully characterised. The aim of this study was to evaluate the experimental and theoretical binding affinity of PVPP towards six phenolic compounds representing different types of phenolic species. The interaction between PVPP and phenolics was evaluated in model solutions, where hydroxyl groups, hydrophobic bonding and steric hindrance were characterised. The results of the study indicated that PVPP exhibits high affinity for quercetin and catechin, moderate affinity for epicatechin, gallic acid and lower affinity for 4-methylcatechol and caffeic acid. The affinity has a direct correlation with the hydroxylation degree of each compound. The results show that the affinity of PVPP towards phenols is related with frontier orbitals. This work demonstrates a direct correlation between the experimental affinity and the interaction energy calculations obtained through computational chemistry methods.

  17. Method and system for the removal of oxides of nitrogen and sulfur from combustion processes

    DOEpatents

    Walsh, John V.

    1987-12-15

    A process for removing oxide contaminants from combustion gas, and employing a solid electrolyte reactor, includes: (a) flowing the combustion gas into a zone containing a solid electrolyte and applying a voltage and at elevated temperature to thereby separate oxygen via the solid electrolyte, (b) removing oxygen from that zone in a first stream and removing hot effluent gas from that zone in a second stream, the effluent gas containing contaminant, (c) and pre-heating the combustion gas flowing to that zone by passing it in heat exchange relation with the hot effluent gas.

  18. Evaluation of a Combined Cyclone and Gas Filtration System for Particulate Removal in the Gasification Process

    SciTech Connect

    Rizzo, Jeffrey J.

    2010-04-30

    cyclonefiltration hybrid unit in the E-Gas (TM) gasification process. These reductions would help to keep the E-Gas (TM) technology competitive among other coal-fired power generation technologies. The Wabash combined cyclone and gas filtration slipstream test program was developed to provide design information, equipment specification and process control parameters of a hybrid cyclone and candle filter particulate removal system in the E-Gas (TM) gasification process that would provide the optimum performance and reliability for future commercial use. The test program objectives were as follows: 1. Evaluate the use of various cyclone materials of construction; 2. Establish the optimal cyclone efficiency that provides stable long term gas filter operation; 3. Determine the particle size distribution of the char separated by both the cyclone and candle filters. This will provide insight into cyclone efficiency and potential future plant design; 4. Determine the optimum filter media size requirements for the cyclone-filtration hybrid unit; 5. Determine the appropriate char transfer rates for both the cyclone and filtration portions of the hybrid unit; 6. Develop operating procedures for the cyclone-filtration hybrid unit; and, 7. Compare the installed capital cost of a scaled-up commercial cyclone-filtration hybrid unit to the current gas filtration design without a cyclone unit, such as currently exists at the Wabash facility.

  19. Effect of temperature on removal of trace organic chemicals in managed aquifer recharge systems.

    PubMed

    Alidina, Mazahirali; Shewchuk, Justin; Drewes, Jörg E

    2015-03-01

    This study was undertaken to investigate whether changes in temperature experienced in MAR systems affect attenuation of trace organic chemicals (TOrCs). A set of laboratory-scale soil columns were placed in a temperature-controlled environmental chamber and operated at five different temperature set-points (30, 20, 10, 8 and 4°C) covering the range of typical groundwater temperatures in cold, moderate and arid climate regions. Removal of bulk organic carbon both in the infiltration zone as well as during deeper infiltration was independent of temperature. Of the 22 TOrCs investigated, only six chemicals exhibited changes in attenuation as a function of temperature. Attenuation of four of the compounds (diclofenac, gemfibrozil, ketoprofen and naproxen) decreased as the temperature was reduced from 30°C to 4°C, likely due to decreased microbial activity at lower temperatures. As the temperature was decreased, however, attenuation of oxybenzone and trimethoprim were noted to increase. This increased attenuation was likely due to more efficient sorption at lower temperatures, though possible changes in the microbial composition as the temperature decreased may also have contributed to this change. Changes in rate constants of attenuation (ka) for the biotransformed TOrCs with temperature suggested the existence of a critical temperature at 10°C for three of the four TOrCs, where significant changes to rates of attenuation occurred. Results from this study indicated that for most TOrCs, changes in temperature do not impact their attenuation. Thus, seasonal changes in temperature are not considered to be a major concern for attenuation of most TOrCs in MAR systems.

  20. Advanced phosphorus recovery using a novel SBR system with granular sludge in simultaneous nitrification, denitrification and phosphorus removal process.

    PubMed

    Lu, Yong-Ze; Wang, Hou-Feng; Kotsopoulos, Thomas A; Zeng, Raymond J

    2016-05-01

    In this study, a novel process for phosphorus (P) recovery without excess sludge production from granular sludge in simultaneous nitrification-denitrification and P removal (SNDPR) system is presented. Aerobic microbial granules were successfully cultivated in an alternating aerobic-anaerobic sequencing batch reactor (SBR) for removing P and nitrogen (N). Dense and stable granular sludge was created, and the SBR system showed good performance in terms of P and N removal. The removal efficiency was approximately 65.22 % for N, and P was completely removed under stable operating conditions. Afterward, new operating conditions were applied in order to enhance P recovering without excess sludge production. The initial SBR system was equipped with a batch reactor and a non-woven cloth filter, and 1.37 g of CH3COONa·3H2O was added to the batch reactor after mixing it with 1 L of sludge derived from the SBR reactor to enhance P release in the liquid fraction, this comprises the new system configuration. Under the new operating conditions, 93.19 % of the P contained in wastewater was released in the liquid fraction as concentrated orthophosphate from part of granular sludge. This amount of P could be efficiently recovered in the form of struvite. Meanwhile, a deterioration of the denitrification efficiency was observed and the granules were disintegrated into smaller particles. The biomass concentration in the system increased firstly and then maintained at 4.0 ± 0.15 gVSS/L afterward. These results indicate that this P recovery operating (PRO) mode is a promising method to recover P in a SNDPR system with granular sludge. In addition, new insights into the granule transformation when confronted with high chemical oxygen demand (COD) load were provided.

  1. Highly efficient removal of chromium(VI) by Fe/Ni bimetallic nanoparticles in an ultrasound-assisted system.

    PubMed

    Zhou, Xiaobin; Jing, Guohua; Lv, Bihong; Zhou, Zuoming; Zhu, Runliang

    2016-10-01

    Highly active Fe/Ni bimetallic nanocomposites were prepared by using the liquid-phase reduction method, and they were proven to be effective for Cr(VI) removal coupled with US irradiation. The US-assisted Fe/Ni bimetallic system could maintain a good performance for Cr(VI) removal at a wide pH range of 3-9. Based on the characterization of the Fe/Ni nanoparticles before and after reaction, the high efficiency of the mixed system could attribute to the synergistic effects of the catalysis of Ni(0) and US cavitation. Ni(0) could facilitate the Cr(VI) reduction through electron transfer and catalytic hydrogenation. Meanwhile, US could fluidize the Fe/Ni nanoparticles to increase the actual reactive surface area and clean off the co-precipitated Fe(III)-Cr(III) hydroxides to maintain the active sites on the surface of the Fe/Ni nanoparticles. Thus, compared with shaking, the US-assisted Fe/Ni system was more efficient on Cr(VI) removal, which achieved 94.7% removal efficiency of Cr(VI) within 10 min. The pseudo-first-order rate constant (kobs) in US-assisted Fe/Ni system (0.5075 min(-1)) was over 5 times higher than that under shaking (0.0972 min(-1)). Moreover, the Fe/Ni nanoparticles still have a good performance under US irradiation after 26 days aging as well as regeneration.

  2. Small System Use of a Solid Arsenic Oxidizing Media in Place of Chemical Oxidation to Enhance Arsenic Removals

    EPA Science Inventory

    As part of the USEPA Arsenic Demonstration Program, an arsenic removal adsorptive media treatment system (10 gpm) was installed at Head Start School in Buckeye Lake, Ohio on June 28, 2006. The source water (ground water) contained around 20 µg/L of arsenic, existing predominatel...

  3. System and method for characterizing voiced excitations of speech and acoustic signals, removing acoustic noise from speech, and synthesizing speech

    DOEpatents

    Burnett, Greg C.; Holzrichter, John F.; Ng, Lawrence C.

    2002-01-01

    Low power EM waves are used to detect motions of vocal tract tissues of the human speech system before, during, and after voiced speech. A voiced excitation function is derived. The excitation function provides speech production information to enhance speech characterization and to enable noise removal from human speech.

  4. ETV REPORT: REMOVAL OF ARSENIC IN DRINKING WATER ORCA WATER TECHNOLOGIES KEMLOOP 1000 COAGULATION AND FILTRATION WATER TREATMENT SYSTEM

    EPA Science Inventory

    Verification testing of the ORCA Water Technologies KemLoop 1000 Coagulation and Filtration Water Treatment System for arsenic removal was conducted at the St. Louis Center located in Washtenaw County, Michigan, from March 23 through April 6, 2005. The source water was groundwate...

  5. Enzyme-catalyzed O2 removal system for electrochemical analysis under ambient air: application in an amperometric nitrate biosensor.

    PubMed

    Plumeré, Nicolas; Henig, Jörg; Campbell, Wilbur H

    2012-03-06

    Electroanalytical procedures are often subjected to oxygen interferences. However, achieving anaerobic conditions in field analytical chemistry is difficult. In this work, novel enzymatic systems were designed to maintain oxygen-free solutions in open, small volume electrochemical cells and implemented under field conditions. The oxygen removal system consists of an oxidase enzyme, an oxidase-specific substrate, and catalase for dismutation of hydrogen peroxide generated in the enzyme catalyzed oxygen removal reaction. Using cyclic voltammetry, three oxidase enzyme/substrate combinations with catalase were analyzed: glucose oxidase with glucose, galactose oxidase with galactose, and pyranose 2-oxidase with glucose. Each system completely removed oxygen for 1 h or more in unstirred open vessels. Reagents, catalysts, reaction intermediates, and products involved in the oxygen reduction reaction were not detected electrochemically. To evaluate the oxygen removal systems in a field sensing device, a model nitrate biosensor based on recombinant eukaryotic nitrate reductase was implemented in commercial screen-printed electrochemical cells with 200 μL volumes. The products of the aldohexose oxidation catalyzed by glucose oxidase and galactose oxidase deactivate nitrate reductase and must be quenched for biosensor applications. For general application, the optimum catalyst is pyranose 2-oxidase since the oxidation product does not interfere with the biorecognition element.

  6. ETV REPORT: REMOVAL OF CHEMICAL CONTAMINANTS IN DRINKING WATER – WATTS PREMIER INC. WP-4V DRINKING WATER TREATMENT SYSTEM

    EPA Science Inventory

    The Watts Premier WP-4V POU drinking water treatment system was tested for removal of aldicarb, benzene, cadmium, carbofuran, cesium, chloroform, dichlorvos, dicrotophos, fenamiphos, mercury, mevinphos, oxamyl, strontium, and strychnine. The WP-4V employs a reverse osmosis (RO) m...

  7. Using a Solid Oxidizing Media to Enhance Arsenic (As[III]) Removal at a Very Small System

    EPA Science Inventory

    An adsorptive media system at the LEADS Head Start School (LHSS) Building in Buckeye Lake, OH, one of the 50 U.S. EPA Arsenic Removal Technology Demonstration sites, was relocated, after modifications, to Plainview Christian School in Plain City, OH to help bring the non-transien...

  8. New Hydrophilic, Composite Membranes for Air Removal from Water Coolant Systems

    NASA Technical Reports Server (NTRS)

    Ritchie, Stephen M. C.; Luo, Qiang; Curtis, Salina S.; Holladay, Jon B.; Clark, Dallas W.

    2004-01-01

    Liquid coolants are commonly used as thermal transport media to increase efficiency and flexibility in aerospace vehicle design. The introduction of gas bubbles into the coolant can have negative consequences, including: loss of centrifugal pump prime, irregular sensor readings, and blockage of coolant flow to remote systems. One solution to mitigate these problems is the development of a passive gas removal device, or gas trap, installed in the flight cooling system. In this study, a new hydrophilic, composite membrane has been developed for passage of the coolant fluid and retention of gas bubbles. The trapped bubbles are subsequently vented from the system by a thin, hydrophobic, microporous membrane. The original design for this work employed a homogeneous membrane that was susceptible to fouling and pore plugging. Spare gas traps of this variety have degraded during storage, and recreation of the membranes has been complicated due to problems with polymer duplication and property variations in the final membranes. In this work, replacements have been developed based on deposition of a hydrophilic polymer on the bore-side of a porous polyethylene (PE) tube. The tube provides excellent chemical and mechanical stability, and the hydrophilic layer provides retention of gas bubbles. Preliminary results have shown that intimate contact is required between the deposited layer and the substrate to overcome material differences. This has been accomplished by presoaking the membrane tube in the solvent to raise its surface energy. Polymer solutions of various concentrations have been used to promote penetration of the polymer layer into the porous substrate and to control separation layer thickness. The resulting composite membranes have shown repeatable decrease in nitrogen permeability, which is indicative of a decrease in membrane pore size. Studies with water permeation have yielded similar results. We have observed some swelling of the added polymer layer, which

  9. Multibody dynamics driving GNC and system design in tethered nets for active debris removal

    NASA Astrophysics Data System (ADS)

    Benvenuto, Riccardo; Lavagna, Michèle; Salvi, Samuele

    2016-07-01

    Debris removal in Earth orbits is an urgent issue to be faced for space exploitation durability. Among different techniques, tethered-nets present appealing benefits and some open points to fix. Former and latter are discussed in the paper, supported by the exploitation of a multibody dynamics tool. With respect to other proposed capture mechanisms, tethered-net solutions are characterised by a safer capturing distance, a passive angular momentum damping effect and the highest flexibility to unknown shape, material and attitude of the target to interface with. They also allow not considering the centre of gravity alignment with thrust axis as a constraint, as it is for any rigid link solution. Furthermore, the introduction of a closing thread around the net perimeter ensures safer and more reliable grasping and holding. In the paper, a six degrees of freedom multibody dynamics simulator is presented: it was developed at Politecnico di Milano - Department of Aerospace Science and Technologies - and it is able to describe the orbital and attitude dynamics of tethered-nets systems and end-bodies during different phases, with great flexibility in dealing with different topologies and configurations. Critical phases as impact and wrapping are analysed by simulation to address the tethered-stack controllability. It is shown how the role of contact modelling is fundamental to describe the coupled dynamics: it is demonstrated, as a major novel contribution, how friction between the net and a tumbling target allows reducing its angular motion, stabilizing the system and allowing safer towing operations. Moreover, the so-called tethered space tug is analysed: after capture, the two objects, one passive and one active, are connected by the tethered-net flexible link, the motion of the system being excited by the active spacecraft thrusters. The critical modes prevention during this phase, by means of a closed-loop control synthesis is shown. Finally, the connection between

  10. In vitro evaluation of efficacy of different rotary instrument systems for gutta percha removal during root canal retreatment

    PubMed Central

    Joseph, Mercy; Malhotra, Amit; Rao, Murali; Sharma, Abhimanyu; Talwar, Sangeeta

    2016-01-01

    Background Complete removal of old filling material during root canal retreatment is fundamental for predictable cleaning and shaping of canal anatomy. Most of the retreatment methods tested in earlier studies have shown inability to achieve complete removal of root canal filling. Therefore the aim of this investigation was to assess the efficacy of three different rotary nickel titanium retreatment systems and Hedstrom files in removing filling material from root canals. Material and Methods Sixty extracted mandibular premolars were decoronated to leave 15 mm root. Specimen were hand instrumented and obturated using gutta percha and AH plus root canal sealer. After storage period of two weeks, roots were retreated with three (Protaper retreatment files, Mtwo retreatment files, NRT GPR) rotary retreatment instrument systems and Hedstroem files. Subsequently, samples were sectioned longitudinally and examined under stereomicroscope. Digital images were recorded and evaluated using Digital Image Analysing Software. The retreatment time was recorded for each tooth using a stopwatch. The area of canal and the residual filling material was recorded in mm2 and the percentage of remaining filling material on canal walls was calculated. Data was analysed using ANOVA test. Results Significantly less amount of residual filling material was present in protaper and Mtwo instrumented teeth (p < 0.05) compared to NRT GPR and Hedstrom files group. Protaper instruments also required lesser time during removal of filling material followed by Mtwo instruments, NRT GPR files and Hedstrom files. Conclusions None of the instruments were able to remove the filling material completely from root canal. Protaper universal retreatment system and Mtwo retreatment files were more efficient and faster compared to NRT GPR fles and Hedstrom files. Key words:Gutta-percha removal, nickel titanium, root canal retreatment, rotary instruments. PMID:27703601

  11. Zero-Valent Metallic Treatment System and Its Application for Removal and Remediation of Polychlorinated Biphenyls (Pcbs)

    NASA Technical Reports Server (NTRS)

    Quinn, Jacqueline W. (Inventor); Clausen, Christian A. (Inventor); Geiger, Cherie L. (Inventor); Brooks, Kathleen B. (Inventor)

    2012-01-01

    PCBs are removed from contaminated media using a treatment system including zero-valent metal particles and an organic hydrogen donating solvent. The treatment system may include a weak acid in order to eliminate the need for a coating of catalytic noble metal on the zero-valent metal particles. If catalyzed zero-valent metal particles are used, the treatment system may include an organic hydrogen donating solvent that is a non-water solvent. The treatment system may be provided as a "paste-like" system that is preferably applied to natural media and ex-situ structures to eliminate PCBs.

  12. Assessing the removal potential of soil-aquifer treatment systems for bulk organic matter.

    PubMed

    Rauch, T; Drewes, J E

    2004-01-01

    The fate of effluent organic matter (EfOM) during groundwater recharge was investigated by studying the removal behavior of four bulk organic carbon fractions isolated from a secondary effluent: Hydrophilic organic matter (HPI), hydrophobic acids (HPO-A), colloidal organic matter (OM), and soluble microbial products (SMPs). Short-term removal of the bulk organic fractions during soil infiltration was simulated in biologically active soil columns. Results revealed that the four organic fractions showed a significantly different behavior with respect to biological removal. HPI and colloidal OM were prone to biological removal during initial soil infiltration (0-30 cm) and supported soil microbial biomass growth in the infiltrative surface. Additionally, colloidal OM was partly removed by physical adsorption or filtration. HPO-A and SMPs reacted recalcitrant towards biological degradation as indicated by low soil biomass activity responses. Adsorbability assessment of the biologically refractory portions of the fractions onto powered activated carbon (PAC) indicated that physical removal is not likely to play a significantly role in further diminishing recalcitrant HPO-A, HPI and SMPs during longer travel times in the subsurface.

  13. Contractions of affine spherical varieties

    SciTech Connect

    Arzhantsev, I V

    1999-08-31

    The language of filtrations and contractions is used to describe the class of G-varieties obtainable as the total spaces of the construction of contraction applied to affine spherical varieties, which is well-known in invariant theory. These varieties are local models for arbitrary affine G-varieties of complexity 1 with a one-dimensional categorical quotient. As examples, reductive algebraic semigroups and three-dimensional SL{sub 2}-varieties are considered.

  14. Effects of unilateral and bilateral cochlea removal on 2-deoxyglucose patterns in the chick auditory system.

    PubMed

    Heil, P; Scheich, H

    1986-10-15

    The 2-deoxyglucose (2DG) method was used to map functional activity in the auditory system of chicks that had been subjected to unilateral or bilateral cochlea removal. Following survival times of 1 day to 4 weeks, chicks were exposed to continuous white noise in the 2DG experiments. In monaural subjects nucleus angularis and nucleus magnocellularis showed faint 2DG uptake on the side contralateral to the intact ear. In the binaural nucleus laminaris, the asymmetrical and almost mirror-imaged labeling pattern (Lippe, Stewart, and Rubel: Brain Res. 196:43-58, '80) was produced. The superior olive (OS) was strongly labeled on the ipsilateral side, whereas the contralateral OS showed only a slight 2DG uptake at its medial border. The lateral lemniscus and nucleus lemnisci lateralis, pars ventralis (LLv) showed stronger activation on the contralateral side. Both Nissl stains and 2DG patterns provide evidence that nucleus ventralis lemnisci lateralis (VLV) can be subdivided into an anterior (VLVa) and a posterior (VLVp) part. Whereas VLVp is labeled only contralaterally, VLVa is labeled on both sides with similar intensity. Nucleus mesencephalicus lateralis, pars dorsalis (MLD) is strongly labeled throughout contralaterally. The ipsilateral MLD shows a defined ventral portion of high 2DG uptake. Intensity of labeling here is symmetrical to the corresponding area of the contralateral MLD. These symmetrical patterns were related to the tonotopic organization of MLD, which was mapped in intact animals by using tone stimuli. Assuming that symmetrical 2DG uptake in monaural animals indicates excitatory input from both ears (EE-cells), it appears that these EE-cells occupy a sector of each isofrequency plane in MLD. Nucleus ovoidalis (Ov) generally was stronger labeled on the contralateral side. The columnar organization of field L as seen in monaural chicks has already been described (Scheich, Exp. Brain Res. 51:199-205, '83). In bilaterally deafened chicks, MLD, Ov, and

  15. Bimetallic Treatment System (BTS) for Removal and Remediation of Polychlorinated Biphenyl from Marshall Space Flight Center's 4696 Fl Stand

    NASA Technical Reports Server (NTRS)

    Quinn, Jacqueline

    2006-01-01

    This Office of Space Flight (OSF)-funded project sought to demonstrate the application of a Bi-metallic Treatment System (BTS) to remove and degrade PCBs found on NASA facilities. The project initiated with the collection of PCB-containing materials from various MSFC and KSC structures, followed by laboratory evaluation of the BTS' PCB-removal efficiency, and concluded with a field demonstration at MSFC. The project evaluated the optimum formulation required to remove PCBs from aged and weathered paint with the goal of achieving final PCB concentrations less than 50 mg/Kg or 50 percent reduction where PCB starting levels were already below the 50 mg/Kg levels. Using lessons learned from this study, it was anticipated that the research team would be better able to make further recommendation on application strategies for future use of BTS for the treatment of PCB laden coatings on structures.

  16. Novel use of the AngioVac® system to remove thrombus during simultaneous extracorporeal membrane oxygenation life support.

    PubMed

    Griffith, Kevin E; Jenkins, Eric; Copenhaver, William; Williams, David M

    2016-03-01

    Extracorporeal membrane oxygenation (ECMO) was introduced to clinical medicine over 40 years ago. While initially used as a treatment for acute respiratory failure in infants, the use of ECMO has grown to include respiratory and circulatory failure in both children and adults, cardiogenic shock, pulmonary embolism, sepsis, trauma, malignancy, pulmonary hemorrhage and as a treatment for hypothermic drowning.(1) Recent technological improvements in ECMO circuitry make it possible to minimize anticoagulation of the ECMO patient, decreasing the incidence of bleeding. Thrombus deposition within the ECMO circuit can be a life-threating complication. ECMO circuit thrombus can be contained in the circuit, adherent to cannula and deposited within the patient. The ability to remove thrombus while the patient remains on ECMO support could be a life-saving measure for some patients. The present case report outlines use of the AngioVac(®) thrombus removal system in concert with ECMO to remove a large thrombus adherent to an ECMO cannula.