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Sample records for separator characterization studies

  1. Phase separation in thermal systems: a lattice Boltzmann study and morphological characterization.

    PubMed

    Gan, Yanbiao; Xu, Aiguo; Zhang, Guangcai; Li, Yingjun; Li, Hua

    2011-10-01

    We investigate thermal and isothermal symmetric liquid-vapor separations via a fast Fourier transform thermal lattice Boltzmann (FFT-TLB) model. Structure factor, domain size, and Minkowski functionals are employed to characterize the density and velocity fields, as well as to understand the configurations and the kinetic processes. Compared with the isothermal phase separation, the freedom in temperature prolongs the spinodal decomposition (SD) stage and induces different rheological and morphological behaviors in the thermal system. After the transient procedure, both the thermal and isothermal separations show power-law scalings in domain growth, while the exponent for thermal system is lower than that for isothermal system. With respect to the density field, the isothermal system presents more likely bicontinuous configurations with narrower interfaces, while the thermal system presents more likely configurations with scattered bubbles. Heat creation, conduction, and lower interfacial stresses are the main reasons for the differences in thermal system. Different from the isothermal case, the release of latent heat causes the changing of local temperature, which results in new local mechanical balance. When the Prandtl number becomes smaller, the system approaches thermodynamical equilibrium much more quickly. The increasing of mean temperature makes the interfacial stress lower in the following way: σ=σ(0)[(T(c)-T)/(T(c)-T(0))](3/2), where T(c) is the critical temperature and σ(0) is the interfacial stress at a reference temperature T(0), which is the main reason for the prolonged SD stage and the lower growth exponent in the thermal case. Besides thermodynamics, we probe how the local viscosities influence the morphology of the phase separating system. We find that, for both the isothermal and thermal cases, the growth exponents and local flow velocities are inversely proportional to the corresponding viscosities. Compared with the isothermal case, the

  2. Whey protein isolate gel for separation: A formation, characterization, and application study

    NASA Astrophysics Data System (ADS)

    Teo, Jiunn Yeong

    performance of WPI monolith for continuous bed chromatography. Nonetheless the WPI monolith may be used to separate different protein molecules based on protein-protein interaction between WPI and protein molecules to be separated.

  3. Airborne rotary separator study

    NASA Technical Reports Server (NTRS)

    Drnevich, R. F.; Nowobilski, J. J.

    1992-01-01

    Several air breathing propulsion concepts for future earth-to-orbit transport vehicles utilize air collection and enrichment, and subsequent storage of liquid oxygen for later use in the vehicle mission. Work performed during the 1960's established the feasibility of substantially reducing weight and volume of a distillation type air separator system by operating the distillation elements in high 'g' fields obtained by rotating the separator assembly. The purpose of this study was to evaluate various fuels and fuel combinations with the objective of minimizing the weight and increase the ready alert capability of the plane. Fuels will be used to provide energy as well as act as heat sinks for the on-board heat rejection system. Fuel energy was used to provide power for air separation as well as to produce refrigeration for liquefaction of oxygen enriched air, besides its primary purpose of vehicle propulsion. The heat generated in the cycle was rejected to the fuel and water which is also carried on board the vehicle.The fuels that were evaluated include JP4, methane, and hydrogen. Hydrogen served as a comparison to the JP4 and methane cases.

  4. Airborne rotary air separator study

    NASA Technical Reports Server (NTRS)

    Acharya, A.; Gottzmann, C. F.; Nowobilski, J. J.

    1990-01-01

    Several air breathing propulsion concepts for future earth-to-orbit transport vehicles utilize air collection and enrichment, and subsequent storage of liquid oxygen for later use in the vehicle emission. Work performed during the 1960's established the feasibility of substantially reducing weight and volume of a distillation type air separator system by operating the distillation elements in high 'g' fields obtained by rotating the separator assembly. This contract studied the capability test and hydraulic behavior of a novel structured or ordered distillation packing in a rotating device using air and water. Pressure drop and flood points were measured for different air and water flow rates in gravitational fields of up to 700 g. Behavior of the packing follows the correlations previously derived from tests at normal gravity. The novel ordered packing can take the place of trays in a rotating air separation column with the promise of substantial reduction in pressure drop, volume, and system weight. The results obtained in the program are used to predict design and performance of rotary separators for air collection and enrichment systems of interest for past and present concepts of air breathing propulsion (single or two-stage to orbit) systems.

  5. LISA Propulsion Module Separation Study

    NASA Technical Reports Server (NTRS)

    Merkowitz, Stephen

    2004-01-01

    The Laser Interferometer Space Antenna (LISA) mission is a space-borne gravitational wave detector consisting of three spacecraft in heliocentric orbit. Each spacecraft is delivered to it operational orbit by a propulsion module. Because of the strict thermal and mass balancing requirements of LISA, the baseline mission concept requires that the propulsion module separate from the sciencecraft after delivery. The only propulsion system currently baselined for the sciencecraft are micronewton level thrusters, such as FEEP or colloid thrusters, that are used to balance the 30-40 microN of solar radiation pressure and provide the drag-free and attitude control of the spacecraft. Due to these thrusters limited authority, the separation of the propulsion module from the sciencecraft must be well controlled to not induce a large tip-off rotation of the sciencecraft. We present here the results of a design study of the propulsion module separation system that is shown to safely deliver the LISA sciencecraft to its final operational orbit.

  6. Characterization of Phase Separation Propensity for Amorphous Spray Dried Dispersions.

    PubMed

    McNamara, Daniel; Yin, Shawn; Pan, Duohai; Crull, George; Timmins, Peter; Vig, Balvinder

    2017-02-06

    A generalized screening approach, applying isothermal calorimetry at 37 °C 100% RH, to formulations of spray dried dispersions (SDDs) for two active pharmaceutical ingredients (APIs) (BMS-903452 and BMS-986034) is demonstrated. APIs 452 and 034, with similar chemotypes, were synthesized and promoted during development for oral dosing. Both APIs were formulated as SDDs for animal exposure studies using the polymer hydroxypropylmethlycellulose acetyl succinate M grade (HPMCAS-M). 452 formulated at 30% (wt/wt %) was an extremely robust SDD that was able to withstand 40 °C 75% RH open storage conditions for 6 months with no physical evidence of crystallization or loss of dissolution performance. Though 034 was a chemical analogue with similar physical chemical properties to 452, a physically stable SDD of 034 could not be formulated in HPMCAS-M at any of the drug loads attempted. This study was used to develop experience with specific physical characterization laboratory techniques to evaluate the physical stability of SDDs and to characterize the propensity of SDDs to phase separate and possibly crystallize. The screening strategy adopted was to stress the formulated SDDs with a temperature humidity screen, within the calorimeter, and to apply orthogonal analytical techniques to gain a more informed understanding of why these SDDs formulated with HPMCAS-M demonstrated such different physical stability. Isothermal calorimetry (thermal activity monitor, TAM) was employed as a primary stress screen wherein the SDD formulations were monitored for 3 days at 37 °C 100% RH for signs of phase separation and possible crystallization of API. Powder X-ray diffraction (pXRD), modulated differential scanning calorimetry (mDSC), Fourier transform infrared spectroscopy (FTIR), and solid state nuclear magnetic resonance (ssNMR) were all used to examine formulated SDDs and neat amorphous drug. 452 SDDs formulated at 30% (wt/wt %) or less did not show phase separation behavior upon

  7. Photovoltaic solar panels of crystalline silicon: Characterization and separation.

    PubMed

    Dias, Pablo Ribeiro; Benevit, Mariana Gonçalves; Veit, Hugo Marcelo

    2016-03-01

    Photovoltaic panels have a limited lifespan and estimates show large amounts of solar modules will be discarded as electronic waste in a near future. In order to retrieve important raw materials, reduce production costs and environmental impacts, recycling such devices is important. Initially, this article investigates which silicon photovoltaic module's components are recyclable through their characterization using X-ray fluorescence, X-ray diffraction, energy dispersion spectroscopy and atomic absorption spectroscopy. Next, different separation methods are tested to favour further recycling processes. The glass was identified as soda-lime glass, the metallic filaments were identified as tin-lead coated copper, the panel cells were made of silicon and had silver filaments attached to it and the modules' frames were identified as aluminium, all of which are recyclable. Moreover, three different components segregation methods have been studied. Mechanical milling followed by sieving was able to separate silver from copper while chemical separation using sulphuric acid was able to detach the semiconductor material. A thermo gravimetric analysis was performed to evaluate the use of a pyrolysis step prior to the component's removal. The analysis showed all polymeric fractions present degrade at 500 °C.

  8. Characterization of Glass Fiber Separator Material for Lithium Batteries

    NASA Technical Reports Server (NTRS)

    Subbarao, S.; Frank, H.

    1984-01-01

    Characterization studies were carried out on a glass fiber paper that is currently employed as a separator material for some LiSOCl2 primary cells. The material is of the non-woven type made from microfilaments of E-type glass and contains an ethyl acrylate binder. Results from extraction studies and tensile testing revealed that the binder content and tensile strength of the paper were significantly less than values specified by the manufacturer. Scanning electron micrographs revealed the presence of clusters of impurities many of which were high in iron content. Results of emission spectroscopy revealed high overall levels of iron and leaching, followed by atomic absorption measurements, revealed that essentially all of this iron is soluble in SOCl2.

  9. Separator Materials Used in Secondary Alkaline Batteries Characterized and Evaluated

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Nickel-cadmium (Ni/Cd) and nickel-hydrogen (Ni/H2) secondary alkaline batteries are vital to aerospace applications. Battery performance and cycle life are significantly affected by the type of separators used in those batteries. A team from NASA Lewis Research Center's Electrochemical Technology Branch developed standardized testing procedures to characterize and evaluate new and existing separator materials to improve performance and cycle life of secondary alkaline batteries. Battery separators must function as good electronic insulators and as efficient electrolyte reservoirs. At present, new types of organic and inorganic separator materials are being developed for Ni/Cd and Ni/H2 batteries. The separator material previously used in the NASA standard Ni/Cd was Pellon 2505, a 100-percent nylon-6 polymer that must be treated with zinc chloride (ZnCl2) to bond the fibers. Because of stricter Environmental Protection Agency regulation of ZnCl2 emissions, the battery community has been searching for new separators to replace Pellon 2505. As of today, two candidate separator materials have been identified; however, neither of the two materials have performed as well as Pellon 2505. The separator test procedures that were devised at Lewis are being implemented to expedite the search for new battery separators. The new test procedures, which are being carried out in the Separator Laboratory at Lewis, have been designed to guarantee accurate evaluations of the properties that are critical for sustaining proper battery operation. These properties include physical and chemical stability, chemical purity, gas permeability, electrolyte retention and distribution, uniformity, porosity, and area resistivity. A manual containing a detailed description of 12 separator test procedures has been drafted and will be used by the battery community to evaluate candidate separator materials for specific applications. These standardized procedures will allow for consistent, uniform

  10. Oligothiophene/graphene supramolecular ensembles managing light induced processes: preparation, characterization, and femtosecond transient absorption studies leading to charge-separation

    NASA Astrophysics Data System (ADS)

    Stergiou, A.; Gobeze, H. B.; Petsalakis, I. D.; Zhao, S.; Shinohara, H.; D'Souza, F.; Tagmatarchis, N.

    2015-09-01

    Advances in organic synthetic chemistry combined with the exceptional electronic properties of carbon allotropes, particularly graphene, is the basis used to design and fabricate novel electron donor-acceptor ensembles with desired properties for technological applications. Thiophene-based materials, which are mainly thiophene-containing polymers, are known for their notable electronic properties. In this frame moving from polymer to oligomer forms, new fundamental information would help for a better understanding of their electrochemical and photophysical properties. Furthermore, a successful combination of their electronic properties with those of graphene is a challenging goal. In this study, two oligothiophene compounds, which consist of three and nine thiophene-rings and are abbreviated 3T and 9T, respectively, were synthesized and noncovalently associated with liquid phase exfoliated few-layered graphene sheets (abbreviated eG), thus forming donor-acceptor 3T/eG and 9T/eG nanoensembes. Markedly, intra-ensemble electronic interactions between the two components in the ground and excited states were evaluated with the aid of UV-Vis and photoluminescence spectroscopy. Furthermore, redox assays revealed the one-electron oxidation of 3T accompanied by one-electron reduction due to eG in 3T/eG, whereas there were two reversible one-electron oxidations of 9T accompanied by one-electron reduction of eG9T/eG. The electrochemical band gap for the 3T/eG and 9T/eG ensembles were calculated and verified, in which the negative free-energy change for the charge-separated state of 3T/eG and 9T/eGvia the singlet excited state of 3T and 9T, respectively, were thermodynamically favorable. Finally, the results of transient pump-probe spectroscopy studies at the femtosecond time scale were supportive of charge transfer type interactions in the 3T/eG and 9T/eG ensembles. The estimated rates for intra-ensemble charge separation were found to be 9.52 × 109 s-1 and 2.2 × 1011 s-1

  11. Characterizing spin-charge separation using Bragg spectroscopy

    NASA Astrophysics Data System (ADS)

    Coleman, Seth T.; Yang, Tsung-Lin; Hulet, Randall G.

    2015-05-01

    One dimensional systems of fermions are predicted by Luttinger liquid theory to have different dispersion relations for the spin and charge excitations. Spin-charge separation has been previously seen in quantum wire tunneling experiments. Ultracold atoms, however, provide a highly tunable and precise system to directly observe this phenomenon. We propose to realize such a system with fermionic 6Li in a 2-D optical lattice, measuring the spin and charge dispersion relations using Bragg spectroscopy. Bragg spectroscopy offers the ability to probe a large region of the excitation spectrum, since it does not change the internal state of the atoms and total momentum transfer is adjustable. By exploiting the tunability of interactions, via a Feshbach resonance, and the adjustability of the optical potential, we will characterize spin-charge separation under a wide range of experimental parameters. Work supported by ARO, ONR, NSF, and The Welch Foundation.

  12. Study Of Phase Separation In Glass

    NASA Technical Reports Server (NTRS)

    Neilson, George F.; Weinberg, Michael C.; Smith, Gary L.

    1989-01-01

    Report describes an experimental study of effect of hydroxide content on phase separation in soda/silica glasses. Ordinary and gel glasses melted at 1,565 degree C, and melts stirred periodically. "Wet" glasses produced by passing bubbles of N2 saturated with water through melts; "dry" glasses prepared in similar manner, except N2 dried before passage through melts. Analyses of compositions of glasses performed by atomic-absorption and index-of-refraction measurements. Authors conclude hydroxide speeds up phase separation, regardless of method (gel or ordinary) by which glass prepared. Eventually helps material scientists to find ways to control morphology of phase separation.

  13. Comparative Study of Airfoil Flow Separation Criteria

    NASA Astrophysics Data System (ADS)

    Laws, Nick; Kahouli, Waad; Epps, Brenden

    2015-11-01

    Airfoil flow separation impacts a multitude of applications including turbomachinery, wind turbines, and bio-inspired micro-aerial vehicles. In order to achieve maximum performance, some devices operate near the edge of flow separation, and others use dynamic flow separation advantageously. Numerous criteria exist for predicting the onset of airfoil flow separation. This talk presents a comparative study of a number of such criteria, with emphasis paid to speed and accuracy of the calculations. We evaluate the criteria using a two-dimensional unsteady vortex lattice method, which allows for rapid analysis (on the order of seconds instead of days for a full Navier-Stokes solution) and design of optimal airfoil geometry and kinematics. Furthermore, dynamic analyses permit evaluation of dynamic stall conditions for enhanced lift via leading edge vortex shedding, commonly present in small flapping-wing flyers such as the bumblebee and hummingbird.

  14. Physical model studies of water column separation

    NASA Astrophysics Data System (ADS)

    Autrique, R.; Rodal, E.; Sánchez, A.; Carmona, L.

    2012-11-01

    Results of physical model studies of water column separation following an upstream valve closure in a horizontal pipe are presented, using three dimensionless parameters: the magnitude of the transient, M, or the ratio between the Joukowsky pressure and the initial absolute head; ΔHr, or the ratio between the maximum overpressure and the Joukowsky pressure, and tcr, the duration of the vapor cavity relative to the pipeline period. Conclusions are derived, aiming to a better understanding of water column separation extreme pressures and to the establishment of useful preliminary design guidelines.

  15. Characterization and Modeling of Materials for Kr-Xe Separations

    SciTech Connect

    Forster, Paul; Naduvalath, Balakrishnan; Czerwinski, Ken

    2015-11-16

    We sought to identify practical adsorbents for the separation of Kr from Xe through pressure swing adsorption. We spent appreciable efforts on two categories of materials: metal-organic frameworks (MOFs) and zeolites. MOFs represent a new and exciting sorbent with numerous new framework topologies and surface chemistries. Zeolites are widely used and available commercial adsorbents. We have employed a combination of gas sorption analysis to analyze gas – surface interactions, computational modelling to both aid in interpreting experimental results and to predict practical adsorbents, and in-situ crystallographic studies to confirm specific experimental results.

  16. Development and characterization of a bilayer separator for lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Huang, Xiaosong

    2011-10-01

    A battery separator is placed between the positive and negative electrodes to prevent electric contact of the electrodes while maintaining good ionic flow. The most commonly used separators for lithium-ion batteries are porous polyolefin membranes. However, they generally do not have good dimentional stability at elevated temperatures. In this study, a bilayer separator has been formed directly on an anode. This bilayer separator comprised a ceramic layer and a porous polyvinylidene fluoride (PVDF) layer. Coin cells with this type of separators showed stable cycling performance at room temperature. They also showed significantly improved rate capabilities compared to the reference cell with a conventional polyolefin separator. An oven test has been used to characterize the cells thermal stability. Charged cells were kept in an oven at 150 °C and their voltage drop was recorded. The reference cell with a conventioal separator failed within about 50 min, while no noticeable voltage drop was observed for the cells with the new bilayer separator within the measured 2 h.

  17. Laboratory studies of water column separation

    NASA Astrophysics Data System (ADS)

    Autrique, R.; Rodal, E.

    2013-12-01

    Results of experimental studies of water column separation following an upstream valve closure are presented. Different geometrical arrangements with transparent PVC pipes are installed immediately downstream of the closing valve, namely, horizontal pipes, vertical pipes flowing down, and humpback profile pipes, the last two being used in order to obtain full pipe section vapor cavities. Maximum over pressures at water column rejoining, and maximum cavity lengths and duration, are compared with theoretical values and with previous experiments with horizontal pipes. Good agreement is found between theory and experiments, and interesting visual material is obtained.

  18. Structural Characterization of Phase Separation in Fe-Cr: A Current Comparison of Experimental Methods

    NASA Astrophysics Data System (ADS)

    Xu, Xin; Odqvist, Joakim; Colliander, Magnus Hörnqvist; Thuvander, Mattias; Steuwer, Axel; Westraadt, Johan E.; King, Stephen; Hedström, Peter

    2016-12-01

    Self-assembly due to phase separation within a miscibility gap is important in numerous material systems and applications. A system of particular interest is the binary alloy system Fe-Cr, since it is both a suitable model material and the base system for the stainless steel alloy category, suffering from low-temperature embrittlement due to phase separation. Structural characterization of the minute nano-scale concentration fluctuations during early phase separation has for a long time been considered a major challenge within material characterization. However, recent developments present new opportunities in this field. Here, we present an overview of the current capabilities and limitations of different techniques. A set of Fe-Cr alloys were investigated using small-angle neutron scattering (SANS), atom probe tomography, and analytical transmission electron microscopy. The complementarity of the characterization techniques is clear, and combinatorial studies can provide complete quantitative structure information during phase separation in Fe-Cr alloys. Furthermore, we argue that SANS provides a unique in-situ access to the nanostructure, and that direct comparisons between SANS and phase-field modeling, solving the non-linear Cahn Hilliard equation with proper physical input, should be pursued.

  19. NREL Studies Carrier Separation and Transport in Perovskite Solar Cells

    SciTech Connect

    2016-01-01

    NREL scientists studied charge separation and transport in perovskite solar cells by determining the junction structure across the solar device using the nanoelectrical characterization technique of Kelvin probe force microscopy. The distribution of electrical potential across both planar and porous devices demonstrates a p-n junction structure at the interface between titanium dioxide and perovskite. In addition, minority-carrier transport within the devices operates under diffusion/drift. Clarifying the fundamental junction structure provides significant guidance for future research and development. This NREL study points to the fact that improving carrier mobility is a critical factor for continued efficiency gains in perovskite solar cells.

  20. Characterizing Continuous Functions in Terms of Separated Sets

    ERIC Educational Resources Information Center

    Lynch, Mark

    2005-01-01

    The following theorem is proved: let f : X --> Y and suppose points are closed in Y (that is, singleton sets are closed in Y ). Then, f is continous if and only if f[1] preserves separated sets. We also give a counter example in the event points are not closed in Y.

  1. Vapor-liquid phase separator studies

    NASA Technical Reports Server (NTRS)

    Yuan, S. W. K.; Lee, J. M.; Kim, Y. I.; Hepler, W. A.; Frederking, T. H. K.

    1983-01-01

    Porous plugs serve as both entropy rejection devices and phase separation components separating the vapor phase on the downstream side from liquid Helium 2 upstream. The liquid upstream is the cryo-reservoir fluid needed for equipment cooling by means of Helium 2, i.e Helium-4 below its lambda temperature in near-saturated states. The topics outlined are characteristic lengths, transport equations and plug results.

  2. SAPO-34 Membranes for N-2/CH4 separation: Preparation, characterization, separation performance and economic evaluation

    SciTech Connect

    Li, SG; Zong, ZW; Zhou, SJ; Huang, Y; Song, ZN; Feng, XH; Zhou, RF; Meyer, HS; Yu, M; Carreon, MA

    2015-08-01

    SAPO-34 membranes were synthesized by several routes towards N-2/CH4 separation. Membrane synthesis parameters including water content in the gel, crystallization time, support pore size, and aluminum source were investigated. High performance N-2-selective membranes were obtained on 100-nm-pore alumina tubes by using Al(i-C3H7O)(3) as aluminum source with a crystallization time of 6 h. These membranes separated N-2 from CH, with N-2 permeance as high as 500 GPU with separation selectivity of 8 at 24 degrees C. for a 50/50 N-2/CH4 mixture. Nitrogen and CH, adsorption isotherms were measured on SAPO-34 crystals. The N-2 and CH, heats of adsorption were 11 and 15 kJ/mol, respectively, which lead to a preferential adsorption of CE-H-4 over N-2 in the N-2/CH4 mixture. Despite this, the SAPO-34 membranes were selective for N-2 over CH4 in the mixture because N-2 diffuses much faster than CH4 and differences in diffusivity played a more critical role than the competitive adsorption. Preliminary economic evaluation indicates that the required N-2/CH4 selectivity would be 15 in order to maintain a CH4 loss below 10%. For small nitrogen-contaminated gas wells, our current SAPO-34 membranes have potential to compete with the benchmark technology cryogenic distillation for N-2 rejection. (C) 2015 Elsevier B.V. All rights reserved,

  3. Separability study of wheat and small grains

    NASA Technical Reports Server (NTRS)

    Lennington, R. K.; Marquina, N. E. (Principal Investigator)

    1978-01-01

    The author has identified the following significant results. Barley showed significant separability from spring wheat, both multitemporally and on a single date chosen near the turning time for barley. Oats showed occasional multitemporal separability from barley and spring wheat; however, the cause of this separability was not well understood. Oats showed no significant separability from spring wheat on any single date during the growing season. By pooling data from segments having an acquisition near the turning time for barley, a fixed unitemporal projection for aiding in the labeling of barley versus spring wheat and oats was constructed. This projection has about the same separability of barley from spring wheat and oats as the unitemporal greeness versus brightness plot. The new fixed projection has the advantage that barley occurs consistently in the same general location on the plot with respect to spring wheat and oats. Attempts to construct a fixed multitemporal or a segment-dependent multitemporal projection for aiding in the labeling of spring wheat versus other small grains were unsuccessful due to segment availability and the fact that each segment has a unique acquisition history.

  4. CHARACTERIZATION OF MICROLENSING PLANETS WITH MODERATELY WIDE SEPARATIONS

    SciTech Connect

    Han, Cheongho

    2009-08-01

    In future high-cadence microlensing surveys, planets can be detected through a new channel of an independent event produced by the planet itself. The two populations of planets to be detected through this channel are wide-separation planets and free-floating planets. Although they appear as similar short timescale events, the two populations of planets are widely different in nature and thus distinguishing them is important. In this paper, we investigate the lensing properties of events produced by planets with moderately wide separations from host stars. We find that the lensing behavior of these events is well described by the Chang-Refsdal lensing, and the shear caused by the primary not only produces a caustic but also makes the magnification contour elongated along the primary-planet axis. The elongated magnification contour implies that the light curves of these planetary events are generally asymmetric, and thus the asymmetry can be used to distinguish the events from those produced by free-floating planets. The asymmetry can be noticed from the overall shape of the light curve and thus can hardly be missed unlike the very short duration central perturbation caused by the caustic. In addition, the asymmetry occurs regardless of the event magnification, and thus the bound nature of the planet can be identified for majority of these events. The close approximation of the lensing light curve to that of the Chang-Refsdal lensing implies that the analysis of the light curve yields only the information about the projected separation between the host star and the planet.

  5. Synthesis and characterization of microporous inorganic membranes for propylene/propane separation

    NASA Astrophysics Data System (ADS)

    Ma, Xiaoli

    Membrane-based gas separation is promising for efficient propylene/propane (C3H6/C3H8) separation with low energy consumption and minimum environment impact. Two microporous inorganic membrane candidates, MFI-type zeolite membrane and carbon molecular sieve membrane (CMS) have demonstrated excellent thermal and chemical stability. Application of these membranes into C3H6/C3H 8 separation has not been well investigated. This dissertation presents fundamental studies on membrane synthesis, characterization and C3H 6/C3H8 separation properties of MFI zeolite membrane and CMS membrane. MFI zeolite membranes were synthesized on α-alumina supports by secondary growth method. Novel positron annihilation spectroscopy (PAS) techniques were used to non-destructively characterize the pore structure of these membranes. PAS reveals a bimodal pore structure consisting of intracrystalline zeolitic micropores of ~0.6 nm in diameter and irregular intercrystalline micropores of 1.4 to 1.8 nm in size for the membranes. The template-free synthesized membrane exhibited a high permeance but a low selectivity in C3H 6/C3H8 mixture separation. CMS membranes were synthesized by coating/pyrolysis method on mesoporous gamma-alumina support. Such supports allow coating of thin, high-quality polymer films and subsequent CMS membranes with no infiltration into support pores. The CMS membranes show strong molecular sieving effect, offering a high C3H 6/C3H8 mixture selectivity of ~30. Reduction in membrane thickness from 500 nm to 300 nm causes an increase in C3H8 permeance and He/N2 selectivity, but a decrease in the permeance of He, N 2 and C3H6 and C3H6/C 3H8 selectivity. This can be explained by the thickness dependent chain mobility of the polymer film resulting in final carbon membrane of reduced pore size with different effects on transport of gas of different sizes, including possible closure of C3H6-accessible micropores. CMS membranes demonstrate excellent C3H6/C 3H8 separation

  6. Synthesis and characterization of mixed matrix membranes for gas separation

    NASA Astrophysics Data System (ADS)

    Zhang, Yanfeng

    2007-12-01

    Mixed-matrix membranes were prepared from Matrimid RTM and mesoporous ZSM-5 nanoparticles containing crystalline ZSM-5. The mesoporous ZSM-5 has both micropores (0.54 nm) and mesopores (2.7 nm), which were confirmed by XRD, nitrogen adsorption, and TEM. The Young's moduli and glass transition temperatures of mixed-matrix membranes are higher than those of pure MatrimidRTM membranes, suggesting that the polymer chains may penetrate into the mesopores. The ideal selectivity for H2/N2 separation increased from 79.6 for pure Matrimid RTM to 143 at 10% loading, while the selectivity of O2/N 2 increased from 6.6 for pure MatrimidRTM to 10.4 at 20% loading. The ideal H2/CH4 separation factor increased from 83.3 to 169 at 20% loading. The results suggest that the mesopores of the ZSM-5 material can provide good interfacial contact between the nanoparticles and the polymer, since the polymer chains can penetrate into the mesopores. The micropores of ZSM-5 crystals can provide size and shape selectivity. A carbon aerogel was prepared by carbonizing a resorcinol-formaldehyde polymer gel at 800°C. Nitrogen adsorption shows the obtained carbon aerogel has both micropores (0.54 nm) and mesopores (2.14 nm). Zeolite A and zeolite Y nanocrystals were grown in the mesopores of the carbon aerogel, resulting in carbon aerogel-zeolite composites. TEM confirmed the existence of nanosize zeolite crystals in the carbon aerogel matrix. Higher selectivity for the CO2/CH4, O2/N2 and H2/N 2 separation were obtained for carbon aerogel-zeolite, carbon aerogel-zeolite-Matrimid RTM membranes. The small pore diameter of zeolite A and the affinity between the CO2 and zeolite crystals make it perfect for CO 2/CH4 separation. Short single-walled carbon nanotubes (SWNT) functionalized with carboxylic acid groups were made and incorporated into MatrimidRTM to form mixed-matrix membranes. SEM images of mixed-matrix membranes cross-sections showed good dispersion and interfacial contact. Pure gas

  7. Interactions Between Antigens and Nanoemulsion Adjuvants: Separation and Characterization Techniques.

    PubMed

    Chan, Michelle Y; Fedor, Dawn M; Phan, Tony; V, Lucien Barnes; Kramer, Ryan M

    2017-01-01

    Determining the association of vaccine components in a formulation is of interest for designing and optimizing well characterized vaccines. Three methods are described to assess interactions between protein antigens and oil-in-water nanoemulsion adjuvants. The methods include (1) ultracentrifugation to measure free versus adjuvant-associated protein, (2) size exclusion chromatography (SEC) to qualitatively assess existing interactions, and (3) Native PAGE as a means to visualize the formulation run in its native state on a polyacrylamide gel. As with many techniques, the methods alone are not definitive, but data from multiple orthogonal assays can provide a more complete picture of protein-adjuvant interactions.

  8. Precision formation flying at megameter separations for exoplanet characterization

    NASA Astrophysics Data System (ADS)

    Scharf, Daniel P.; Martin, Stefan R.; Liebe, Carl Christian; Rahman, Zahidul H.; Seubert, Carl R.; Noecker, Martin Charles; Purcell, George H.

    2016-06-01

    Starshade missions offer a near-term capability to measure the spectra of Earth-sized exoplanets, searching for possible bio-indicators. To function, a starshade and telescope separated by approximately 50 Mm must align to the meter-level on the line to the target star. From the telescope's perspective, this alignment in turn requires sensing the bearing between target star and starshade to approximately 1 milli-arcsecond (5 nrad). Previously, several fine bearing sensors have been proposed based on pupil images of the starshade's shadow. In this paper, a fine bearing sensor is presented based on measuring in the focal plane the bearing between a laser beacon on the starshade and the diffracted centroid of the target star that "leaks" around the starshade outside the science wavelengths. Coarse and medium bearing sensors are also introduced that allow for autonomous operation. The performance of extended Kalman filters using the bearing sensors is presented, as well as deadbanding performance in science mode.

  9. A Regenerable VOC Control System (RVCS) for Characterizing Properties of Sorbents Used in Separation Technologies

    NASA Technical Reports Server (NTRS)

    Nolek, Sara D.; Monje, Oscar A.

    2010-01-01

    This slide presentation reviews the design, method of operation, and testing of a regenerable Volatile Organic Compound (VOC) control system that characterizes properties of sorbents used in separation technologies.

  10. Characterization and separation of ash from CANMET coprocessing residue by oil phase agglomeration techniques

    SciTech Connect

    Majid, A.; Coleman, R.D.; Toll, R.; Pleizier, G.; Deslandes, Y.; Sparks, B.D.; Ikura, M.

    1993-12-31

    CANMET`s coal/heavy oil coprocessing unit yields a solid residue that contains most of the ash originally associated with the feed coal as well as reacted catalyst solids. Removal of these ash solids would make it possible to recycle the material to extinction, thereby increasing production of lighter oils. In this investigation the authors have used surface characterization techniques such as Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDXA) and X-ray Photoelectron Spectroscopy (XPS) to characterize toluene insoluble solids associated with the pitch residue, in order to evaluate the separation potential using oil phase agglomeration techniques. Washability studies using float-sink tests were also carried out to determine empirically the level of ash separation attainable. Based on the results of these studies several tests were carried out to beneficiate the organic matter in the residue pitch, by using liquid phase agglomeration techniques. Levels of ash rejection in these tests ranged from 20% to 40%. SEM and EDXA analysis of the agglomerated product and the reject material and Inductively Coupled Plasma (ICP) analysis of the ash from both materials suggest that most of the iron from added catalyst is retained in the agglomerates.

  11. Preparation and characterization of composite membrane for high temperature gas separation

    SciTech Connect

    Ilias, S.; King, F.G.; Su, N.

    1994-10-01

    The objective of this project is to develop thin film palladium membranes for separation of hydrogen in high temperature applications. The authors plan to use electroless plating to deposit thin palladium films on microporous ceramic and silver substrates and then characterize the membrane in terms of permeability and selectivity for gas separation. To accomplish the research objective, the project requires three tasks: Development of a process for composite membrane fabrication; Characterization of composite membrane; and Development of theoretical model for hydrogen gas separation. The experimental procedures are described.

  12. Characterization and separation of Cryptosporidium and Giardia cells using on-chip dielectrophoresis

    PubMed Central

    Narayanan Unni, Harikrishnan; Hartono, Deny; Yue Lanry Yung, Lin; Mah-Lee Ng, Mary; Pueh Lee, Heow; Cheong Khoo, Boo; Lim, Kian-Meng

    2012-01-01

    Dielectrophoresis (DEP) has been shown to have significant potential for the characterization of cells and could become an efficient tool for rapid identification and assessment of microorganisms. The present work is focused on the trapping, characterization, and separation of two species of Cryptosporidium (C. parvum and C. muris) and Giardia lambia (G. lambia) using a microfluidic experimental setup. Cryptosporidium oocysts, which are 2-4 μm in size and nearly spherical in shape, are used for the preliminary stage of prototype development and testing. G. lambia cysts are 8–12 μm in size. In order to facilitate effective trapping, simulations were performed to study the effects of buffer conductivity and applied voltage on the flow and cell transport inside the DEP chip. Microscopic experiments were performed using the fabricated device and the real part of Clausius—Mossotti factor of the cells was estimated from critical voltages for particle trapping at the electrodes under steady fluid flow. The dielectric properties of the cell compartments (cytoplasm and membrane) were calculated based on a single shell model of the cells. The separation of C. muris and G. lambia is achieved successfully at a frequency of 10 MHz and a voltage of 3 Vpp (peak to peak voltage). PMID:22662073

  13. Magnetic separation studies on ferruginous chromite fine to enhance Cr:Fe ratio

    NASA Astrophysics Data System (ADS)

    Tripathy, Sunil Kumar; Banerjee, P. K.; Suresh, Nikkam

    2015-03-01

    The Cr:Fe ratio (chromium-to-iron mass ratio) of chromite affects the production of chrome-based ferroalloys. Although the literature contains numerous reports related to the magnetic separation of different minerals, limited work concerning the application of magnetic separation to fine chromite from the Sukinda region of India to enhance its Cr:Fe ratio has been reported. In the present investigation, magnetic separation and mineralogical characterization studies of chromite fines were conducted to enhance the Cr:Fe ratio. Characterization studies included particle size and chemical analyses, X-ray diffraction analysis, automated mineral analysis, sink-and-float studies, and magnetic susceptibility measurements, whereas magnetic separation was investigated using a rare earth drum magnetic separator, a rare earth roll magnetic separator, an induced roll magnetic separator, and a wet high-intensity magnetic separator. The fine chromite was observed to be upgraded to a Cr:Fe ratio of 2.2 with a yield of 55.7% through the use of an induced roll magnetic separator and a feed material with a Cr:Fe ratio of 1.6.

  14. Separation of organic ion exchange resins from sludge -- engineering study

    SciTech Connect

    Duncan, J.B.

    1998-08-25

    This engineering study evaluates the use of physical separation technologies to separate organic ion exchange resin from KE Basin sludge prior to nitric acid dissolution. This separation is necessitate to prevent nitration of the organics in the acid dissolver. The technologies under consideration are: screening, sedimentation, elutriation. The recommended approach is to first screen the Sludge and resin 300 microns then subject the 300 microns plus material to elutriation.

  15. Preparation and characterization of N-methylene phosphonic and quaternized chitosan composite membranes for electrolyte separations.

    PubMed

    Saxena, Arunima; Kumar, Arvind; Shahi, Vinod K

    2006-11-15

    Chitosan was functionalized either by introducing a phosphonic acid group or by quaternization of existing primary ammonium groups in order to make it a water-soluble material. Functionalized chitosans and poly(vinyl alcohol) (PVA)-based nanoporous charged membranes were prepared in aqueous media and gelated in methanol at 10 degrees C to tailor their pore structure. These membranes were extensively characterized for their physicochemical, electrochemical, and permeation characteristics using FTIR, TGA, DSC, water content, ion-exchange capacity, ionic transport properties, and membrane permeability studies. N-Methylene phosphonic chitosan (NMPC)/PVA-based membranes exhibited mild cation selectivity and quaternized chitosan (QC)/PVA composite membranes had mild anion selectivity, while a blend of NMPC-QC/PVA membranes exhibited weak cation selectivity because of formation of zwitterionic structure. Viscosity measurements and interaction studies for individual and mixed solutions of NMPC and QC were carried out for the prediction of charge interactions between -PO3H2 and -N+(CH3)3 groups and effect on molecular weight due to functionalization. Elaborate electrochemical and permeation experiments were conducted in order to predict suitability of these membranes for the separation of mono- and bivalent electrolytes based on their hydrated ionic radius, and it was found that among all the synthesized membranes, PC/QC-30 had the highest relative permeability, which may extend its suitability for electrolyte separations. Observations were correlated with equivalent pore radius of the different membranes as estimated by membrane permeability measurements.

  16. Structural characterization of bacterial lipopolysaccharides with mass spectrometry and on- and off-line separation techniques.

    PubMed

    Kilár, Anikó; Dörnyei, Ágnes; Kocsis, Béla

    2013-01-01

    The focus of this review is the application of mass spectrometry to the structural characterization of bacterial lipopolysaccharides (LPSs), also referred to as "endotoxins," because they elicit the strong immune response in infected organisms. Recently, a wide variety of MS-based applications have been implemented to the structure elucidation of LPS. Methodological improvements, as well as on- and off-line separation procedures, proved the versatility of mass spectrometry to study complex LPS mixtures. Special attention is given in the review to the tandem mass spectrometric methods and protocols for the analyses of lipid A, the endotoxic principle of LPS. We compare and evaluate the different ionization techniques (MALDI, ESI) in view of their use in intact R- and S-type LPS and lipid A studies. Methods for sample preparation of LPS prior to mass spectrometric analysis are also described. The direct identification of intrinsic heterogeneities of most intact LPS and lipid A preparations is a particular challenge, for which separation techniques (e.g., TLC, slab-PAGE, CE, GC, HPLC) combined with mass spectrometry are often necessary. A brief summary of these combined methodologies to profile LPS molecular species is provided.

  17. Characterization of a new mobility separation tool: HRIMS as differential mobility analyzer.

    PubMed

    Bouza, Marcos; López-Vidal, Silvia; Pisonero, Jorge; Bordel, Nerea; Pereiro, Rosario; Sanz-Medel, Alfredo

    2014-12-01

    High resolution ion mobility spectrometer (HRIMS) is a new instrument that uses parallel plate Differential Mobility Analysis as principle of separation. Gas phase analysis of volatile organic compounds (VOCs) has been performed for the characterization of this new mobility system using an UV-lamp for ionization. Studies of the effect of temperature and the presence of a desiccant are detailed. Identification of the different peaks obtained with an electrometer was successfully carried out for a group of alcohols, aromatic compounds and ketones (ethanol, 1-propanol, isopropanol, 1-butanol, 1-pentanol, 1-heptanol, acetone, 2-butanone, 2-pentanone, 2-octanone, benzene, toluene, xylene and bromobenzene) following a modified Millikan equation. Moreover, the investigation of the discrimination capabilities within the different VOCs families as well as the mobility dependence with molecular mass was successfully achieved.

  18. Extraction, separation, and intramolecular carbon isotope characterization of athabasca oil sands acids in environmental samples.

    PubMed

    Ahad, Jason M E; Pakdel, Hooshang; Savard, Martine M; Simard, Marie-Christine; Smirnoff, Anna

    2012-12-04

    Here we report a novel approach to extract, isolate, and characterize high molecular weight organic acids found in the Athabasca oil sands region using preparative capillary gas chromatography (PCGC) followed by thermal conversion/elemental analysis-isotope ratio mass spectrometry (TC/EA-IRMS). A number of different "naphthenic acids" surrogate standards were analyzed as were samples from the bitumen-rich unprocessed McMurray Formation, oil sands process water, groundwater from monitoring wells, and surface water from the Athabasca River. The intramolecular carbon isotope signature generated by online pyrolysis (δ(13)C(pyr)) showed little variation (±0.6‰) within any given sample across a large range of mass fractions separated by PCGC. Oil sand, tailings ponds, and deep McMurray Formation groundwater were significantly heavier (up to ∼9‰) compared to surface water and shallow groundwater samples, demonstrating the potential use of this technique in source apportionment studies.

  19. Remotely detected NMR for the characterization of flow and fast chromatographic separations using organic polymer monoliths.

    PubMed

    Teisseyre, Thomas Z; Urban, Jiri; Halpern-Manners, Nicholas W; Chambers, Stuart D; Bajaj, Vikram S; Svec, Frantisek; Pines, Alexander

    2011-08-01

    An application of remotely detected magnetic resonance imaging is demonstrated for the characterization of flow and the detection of fast, small molecule separations within hypercrosslinked polymer monoliths. The hyper-cross-linked monoliths exhibited excellent ruggedness, with a transit time relative standard deviation of less than 2.1%, even after more than 300 column volumes were pumped through at high pressure and flow. Magnetic resonance imaging enabled high-resolution intensity and velocity-encoded images of mobile phase flow through the monolith. The images confirm that the presence of a polymer monolith within the capillary disrupts the parabolic laminar flow profile that is characteristic of mobile phase flow within an open tube. As a result, the mobile phase and analytes are equally distributed in the radial direction throughout the monolith. Also, in-line monitoring of chromatographic separations of small molecules at high flow rates is shown. The coupling of monolithic chromatography columns and NMR provides both real-time peak detection and chemical shift information for small aromatic molecules. These experiments demonstrate the unique power of magnetic resonance, both direct and remote, in studying chromatographic processes.

  20. Preparation and characterization of a Lithium-ion battery separator from cellulose nanofibers.

    PubMed

    Zhang, Hongfeng; Wang, Xiwen; Liang, Yun

    2015-10-01

    Optimizing the desired properties for stretch monolayer separators used in Lithium-ion batteries has been a challenge. In the present study a cellulose nanofiber/PET nonwoven composite separator is successfully fabricated, using a wet-laid nonwoven (papermaking) process, which can attain optimal properties in wettability, mechanical strength, thermal resistance, and electrochemical performance simultaneously. The PET nonwoven material, which is fabricated from ultrafine PET fibers by a wet-laid process, is a mechanical support layer. The porous structure of the composite separator was created by cellulose nanofibers coating the PET in a papermaking process. Cellulose nanofibers (CNFs), which are an eco-friendly sustainable resource, have been drawing considerable attention due to their astounding properties, such as: incredible specific surface area, thermal and chemical stability, high mechanical strength and hydrophilicity. The results show that the CNF separator exhibits higher porosity (70%) than a PP (polypropylene) separator (40%). The CNF separator can also be wetted by electrolyte in a few seconds while a PP separator cannot be entirely wetted after 1 min. The CNF separator has an electrolyte uptake of 250%, while a PP separator has only 65%. Another notable finding is that the CNF separator has almost no shrinkage when exposed to 180 °C for 1 h, whereas a PP separator shrinks by more than 50%. Differential Scanning Calorimetry (DSC) shows that the CNF separator has a higher melting point than a PP separator. These findings all indicate that the CNF 29 separator will be more favorable than stretch film for use in Lithium-ion batteries.

  1. Separation efficiency in a whirlpool surface tension separator, separating faeces and toilet paper for nutrient recovery--pilot-scale study.

    PubMed

    Vinnerås, B

    2004-01-01

    The main proportion of the plant nutrients in waste from society can be recycled in two unpolluted fractions if the urine and the faeces are collected separately. By using urine-diverting toilets combined with a whirlpool surface tension faecal separator, it is possible to achieve this. If the separator is installed correctly, with a gradual bend to minimise disintegration of the particles, it is possible to collect approximately 92% nitrogen, 86% phosphorus and 76% potassium of the content excreted in the faeces in a small separated fraction that only contains 10% of the flushwater used. The faecal separation is a robust system with no moving parts, which is not significantly affected by the flushwater volume, and almost no water is separated to the separated solids if neither toilet paper nor faeces are flushed.

  2. Battery Separator Characterization and Evaluation Procedures for NASA's Advanced Lithium-Ion Batteries

    NASA Technical Reports Server (NTRS)

    Baldwin, Richard S.; Bennet, William R.; Wong, Eunice K.; Lewton, MaryBeth R.; Harris, Megan K.

    2010-01-01

    To address the future performance and safety requirements for the electrical energy storage technologies that will enhance and enable future NASA manned aerospace missions, advanced rechargeable, lithium-ion battery technology development is being pursued within the scope of the NASA Exploration Technology Development Program s (ETDP's) Energy Storage Project. A critical cell-level component of a lithium-ion battery which significantly impacts both overall electrochemical performance and safety is the porous separator that is sandwiched between the two active cell electrodes. To support the selection of the optimal cell separator material(s) for the advanced battery technology and chemistries under development, laboratory characterization and screening procedures were established to assess and compare separator material-level attributes and associated separator performance characteristics.

  3. Fundamental study of phosphor separation by controlling magnetic force

    NASA Astrophysics Data System (ADS)

    Wada, Kohei; Mishima, Fumihito; Akiyama, Yoko; Nishijima, Shigehiro

    2013-11-01

    The phosphor wastes consist of phosphors with different emission colors, green (LAP), red (YOX), blue (BAM) and white (HP). It is required to recover and reuse the rare earth phosphors with high market value. In this study, we tried to separate the phosphor using the magnetic separation by HTS bulk magnet utilizing the differences of magnetic susceptibility by the type of phosphors. We succeeded in the successive separation of HP with low market value from YOX and BAM including the rare earth using the magnetic Archimedes method. In this method, vertical and radial components of the magnetic force were used.

  4. Separation-Individuation of Late Adolescents : A Longitudinal Study

    ERIC Educational Resources Information Center

    Aslan, Sevda; Gelbal, Selahattin

    2016-01-01

    The aim of this study was to demonstrate the change in separation-individuation between late adolescents in the first, second, third and fourth year of higher education. The study sample used for this longitudinal study consisted of 148 students attending class studies, computer education and science education departments of Kirikkale University.…

  5. Advanced Characterization of Molecular Interactions in TALSPEAK-like Separations Systems

    SciTech Connect

    Nash, Kenneth; Guelis, Artem; Lumetta, Gregg J.; Sinkov, Sergey

    2015-10-21

    Combining unit operations in advanced aqueous reprocessing schemes brings obvious process compactness advantages, but at the same time greater complexity in process design and operation. Unraveling these interactions requires increasingly sophisticated analytical tools and unique approaches for adequate analysis and characterization that probe molecular scale interactions. Conventional slope analysis methods of solvent extraction are too indirect to provide much insight into such interactions. This project proposed the development and verification of several analytical tools based on studies of TALSPEAK-like aqueous processes. As such, the chemistry of trivalent fission product lanthanides, americium, curium, plutonium, neptunium and uranium figure prominently in these studies. As the project was executed, the primary focus fell upon the chemistry or trivalent lanthanides and actinides. The intent of the investigation was to compare and contrast the results from these various complementary techniques/studies to provide a stronger basis for predicting the performance of extractant/diluent mixtures as media for metal ion separations. As many/most of these techniques require the presence of metal ions at elevated concentrations, it was expected that these studies would take this investigation into the realm of patterns of supramolecular organization of metal complexes and extractants in concentrated aqueous/organic media. We expected to advance knowledge of the processes that enable and limit solvent extraction reactions as a result of the application of fundamental chemical principles to explaining interactions in complex media.

  6. Characterization of Athabasca Asphaltenes Separated Physically and Chemically Using Small-Angle X-Ray Scattering

    NASA Astrophysics Data System (ADS)

    Amundarain Hurtado, Jesus Leonardo

    Athabasca asphaltenes were characterized using small-angle X-ray scattering (SAXS) with synchrotron radiation. Two methods were used to separate asphaltenes from Athabasca bitumen. Conventional chemical separation by precipitation with n-pentane, and physical separation realized by passing bitumen through a zirconia membrane with a 20 nm average pore size. The Athabasca permeates and chemically separated samples were dispersed in 1-methylnaphtalene and n-dodecane, with temperature and asphaltene concentration ranges of 50-310 °C and 1-8 wt. %, respectively. Two approaches were also taken in the analysis of the SAXS emissions. A model-independent approach provided radii of gyration and scattering coefficients. A model-dependent fit provided size distributions for asphaltenes aggregates assuming that they are dense and spherical. Physically and chemically separated asphaltenes showed significant differences in nominal size and structure, and their structural properties exhibited different temperature dependencies. The results challenge the merits of using chemically separated asphaltene properties as a basis for asphaltene property prediction in crude oil/bitumen.

  7. Characterization of Physically and Chemically Separated Athabasca Asphaltenes Using Small-Angle X-ray Scattering

    SciTech Connect

    Amundaraín Hurtado, Jesús Leonardo; Chodakowski, Martin; Long, Bingwen; Shaw, John M.

    2012-02-07

    Athabasca asphaltenes were characterized using small-angle X-ray scattering (SAXS). Two methods were used to separate asphaltenes from the Athabasca bitumen: namely, chemical separation by precipitation with n-pentane and physical separation by nanofiltration using a zirconia membrane with a 20 nm average pore size. The permeate and chemically separated samples were diluted in 1-methylnaphtalene and n-dodecane prior to SAXS measurements. The temperature and asphaltene concentration ranges were 50-310 C and 1-10.4 wt %, respectively. Model-independent analysis of SAXS data provided the radius of gyration and the scattering coefficients. Model-dependent fits provided size distributions for asphaltenes assuming that they are dense and spherical. Model-independent analysis for physically and chemically separated asphaltenes showed significant differences in nominal size and structure, and the temperature dependence of structural properties. The results challenge the merits of using chemically separated asphaltene properties as a basis for asphaltene property prediction in hydrocarbon resources. While the residuals for model-dependent fits are small, the results are inconsistent with the structural parameters obtained from model-independent analysis.

  8. Device for two-dimensional gas-phase separation and characterization of ion mixtures

    DOEpatents

    Tang, Keqi; Shvartsburg, Alexandre A.; Smith, Richard D.

    2006-12-12

    The present invention relates to a device for separation and characterization of gas-phase ions. The device incorporates an ion source, a field asymmetric waveform ion mobility spectrometry (FAIMS) analyzer, an ion mobility spectrometry (IMS) drift tube, and an ion detector. In one aspect of the invention, FAIMS operating voltages are electrically floated on top of the IMS drift voltage. In the other aspect, the FAIMS/IMS interface is implemented employing an electrodynamic ion funnel, including in particular an hourglass ion funnel. The present invention improves the efficiency (peak capacity) and sensitivity of gas-phase separations; the online FAIMS/IMS coupling creates a fundamentally novel two-dimensional gas-phase separation technology with high peak capacity, specificity, and exceptional throughput.

  9. Preparation and Characterization of Cross-linked Phospholipid Bilayer Capillary Coatings for Protein Separations

    PubMed Central

    Mansfield, Elisabeth; Ross, Eric E.; Aspinwall, Craig A.

    2009-01-01

    Analysis of protein and peptide mixtures via capillary electrophoresis is hindered by non-specific adsorption of analytes to the capillary walls, resulting in poor separations and quantitative reproducibility. Phospholipid bilayer (PLB) coatings are very promising for improving protein and peptide separations due to the native resistance to non-specific protein adsorption offered by PLBs; however, these coatings display limited chemical and temporal stability. Here, we show the preparation and characterization of a highly cross-linked, polymerized phospholipid capillary coating prepared using bis-SorbPC. Poly(bis-SorbPC) PLB coatings are prepared in situ within fully enclosed fused silica capillaries via self assembly and radical polymerization. Polymerization of the PLB coating stabilizes the membrane against desorption from the surface and migration in an electric field, improves the temporal and chemical stability, and allows for the separation of both cationic and anionic proteins, while preserving the native resistance to non-specific protein adsorption of natural PLBs. PMID:17373774

  10. Geometric characterization of separability and entanglement in pure Gaussian states by single-mode unitary operations

    NASA Astrophysics Data System (ADS)

    Adesso, Gerardo; Giampaolo, Salvatore M.; Illuminati, Fabrizio

    2007-10-01

    We present a geometric approach to the characterization of separability and entanglement in pure Gaussian states of an arbitrary number of modes. The analysis is performed adapting to continuous variables a formalism based on single subsystem unitary transformations that has been recently introduced to characterize separability and entanglement in pure states of qubits and qutrits [S. M. Giampaolo and F. Illuminati, Phys. Rev. A 76, 042301 (2007)]. In analogy with the finite-dimensional case, we demonstrate that the 1×M bipartite entanglement of a multimode pure Gaussian state can be quantified by the minimum squared Euclidean distance between the state itself and the set of states obtained by transforming it via suitable local symplectic (unitary) operations. This minimum distance, corresponding to a , uniquely determined, extremal local operation, defines an entanglement monotone equivalent to the entropy of entanglement, and amenable to direct experimental measurement with linear optical schemes.

  11. Geometric characterization of separability and entanglement in pure Gaussian states by single-mode unitary operations

    SciTech Connect

    Adesso, Gerardo; Giampaolo, Salvatore M.; Illuminati, Fabrizio

    2007-10-15

    We present a geometric approach to the characterization of separability and entanglement in pure Gaussian states of an arbitrary number of modes. The analysis is performed adapting to continuous variables a formalism based on single subsystem unitary transformations that has been recently introduced to characterize separability and entanglement in pure states of qubits and qutrits [S. M. Giampaolo and F. Illuminati, Phys. Rev. A 76, 042301 (2007)]. In analogy with the finite-dimensional case, we demonstrate that the 1xM bipartite entanglement of a multimode pure Gaussian state can be quantified by the minimum squared Euclidean distance between the state itself and the set of states obtained by transforming it via suitable local symplectic (unitary) operations. This minimum distance, corresponding to a, uniquely determined, extremal local operation, defines an entanglement monotone equivalent to the entropy of entanglement, and amenable to direct experimental measurement with linear optical schemes.

  12. Preparation and characterization of monodisperse large-porous silica microspheres as the matrix for protein separation.

    PubMed

    Xia, Hongjun; Wan, Guangping; Zhao, Junlong; Liu, Jiawei; Bai, Quan

    2016-11-04

    High performance liquid chromatography (HPLC) is a kind of efficient separation technology and has been used widely in many fields. Micro-sized porous silica microspheres as the most popular matrix have been used for fast separation and analysis in HPLC. In this paper, the monodisperse large-porous silica microspheres with controllable size and structure were successfully synthesized with polymer microspheres as the templates and characterized. First, the poly(glycidyl methacrylate-co-ethyleneglycol dimethacrylate) microspheres (PGMA-EDMA) were functionalized with tetraethylenepentamine (TEPA) to generate amino groups which act as a catalyst in hydrolysis of tetraethyl orthosilicate (TEOS) to form Si-containing low molecular weight species. Then the low molecular weight species diffused into the functionalized PGMA-EDMA microspheres by induction force of the amino groups to form polymer/silica hybrid microspheres. Finally, the organic polymer templates were removed by calcination, and the large-porous silica microspheres were obtained. The compositions, morphology, size distribution, specific surface area and pore size distribution of the porous silica microspheres were characterized by infrared analyzer, scanning-electron microscopy, dynamic laser scattering, the mercury intrusion method and thermal gravimetric analysis, respectively. The results show that the agglomeration of the hybrid microspheres can be overcome when the templates were functionalized with TEPA as amination reagent, and the yield of 95.7% of the monodisperse large-porous silica microspheres can be achieved with high concentration of polymer templates. The resulting large-porous silica microspheres were modified with octadecyltrichlorosilane (ODS) and the chromatographic evaluation was performed by separating the proteins and the digest of BSA. The baseline separation of seven kinds of protein standards was achieved, and the column delivered a better performance when separating BSA digests

  13. Synthesis and Characterization of Thiazolium-Based Room Temperature Ionic Liquids for Gas Separations

    SciTech Connect

    Hillesheim, Patrick C; Mahurin, Shannon Mark; Fulvio, Pasquale F; Yeary, Joshua S; Oyola, Yatsandra; Jiang, Deen; Dai, Sheng

    2012-01-01

    A series of novel thiazolium-bis(triflamide) based ionic liquids has been synthesized and characterized. Physicochemical properties of the ionic liquids such as thermal stability, phase transitions, and infrared spectra were analysed and compared to the imidazolium-based congeners. Several unique classes of ancillary substitutions are examined with respect to impacts on overall structure, in addition to their carbon dioxide absorption properties in supported ionic-liquid membranes for gas separation.

  14. Synthesis and Characterization of Thiazolium-Based Room Temperature Ionic Liquids for Gas Separations

    SciTech Connect

    Hillesheim, PC; Mahurin, SM; Fulvio, PF; Yeary, JS; Oyola, Y; Jiang, DE; Dai, S

    2012-09-05

    A series of novel thiazolium-bis(triflamide) based ionic liquids has been synthesized and characterized. Physicochemical properties of the ionic liquids such as thermal stability, phase transitions, and infrared spectra were analyzed and compared to the imidazolium-based congeners. Several unique classes of ancillary substitutions are examined with respect to impacts on overall structure, in addition to their carbon dioxide absorption properties in supported ionic-liquid membranes for gas separation.

  15. Size-separation characterization of starch and glycogen for biosynthesis-structure-property relationships.

    PubMed

    Gilbert, Robert G

    2011-02-01

    Starch and glycogen are highly branched polymers of glucose of great importance to humans in managing and mitigating nutrition-related diseases, especially diabetes and obesity, and in industrial uses, for example in food and paper-making. Size-separation characterization using multiple-detection size-exclusion chromatography (SEC, also known as gel-permeation chromatography, GPC) is able to furnish substantial amounts of information on the relationships between the biosynthesis, processing, structure, and properties of these biopolymers, and achieves superior characterization for use in industrial product and process improvements. Multi-detector SEC is able to give much more information about structure than simple averages such as total molecular weight or size; the detailed information yielded by this technique has already given new information on important biosynthesis-structure-property reactions, and has considerable potential in this field in the future. However, it must be used with care to avoid artifacts arising from incomplete dissolution of the substrate and shear scission during separation. It is also essential in interpreting data to appreciate that this size-separation technique can only ever give size distributions, never true molecular weight distributions. Other size-separation techniques, particularly field-flow fractionation, require substantial technical development to be used on undegraded native starches.

  16. Mechanical modeling of battery separator based on microstructure image analysis and stochastic characterization

    NASA Astrophysics Data System (ADS)

    Xu, Hongyi; Zhu, Min; Marcicki, James; Yang, Xiao Guang

    2017-03-01

    A microstructure-based modeling method is developed to predict the mechanical behaviors of lithium-ion battery separators. Existing battery separator modeling methods cannot capture the structural features on the microscale. To overcome this issue, we propose an image-based microstructure Representative Volume Element (RVE) modeling method, which facilitates the understanding of the separators' complex macro mechanical behaviors from the perspective of microstructural features. A generic image processing workflow is developed to identify different phases in the microscopic image. The processed RVE image supplies microstructural information to the Finite Element Analysis (FEA). Both mechanical behavior and microstructure evolution are obtained from the simulation. The evolution of microstructure features is quantified using the stochastic microstructure characterization methods. The proposed method successfully captures the anisotropic behavior of the separator under tensile test, and provides insights into the microstructure deformation, such as the growth of voids. We apply the proposed method to a commercially available separator as the demonstration. The analysis results are validated using experimental testing results that are reported in literature.

  17. Study on three-dimensional separation in diffusers

    NASA Astrophysics Data System (ADS)

    Jeyapaul, Elbert; Durbin, Paul

    2009-11-01

    A family of three-dimensional diffusers having the same adverse pressure gradient but varying inlet aspect ratios have been studied by detached eddy simulation and Reynolds averaged computation. They provide a geometry for fundamental study of three-dimensional, turbulent separation. The diffuser has a rectangular cross section with two flared walls. RANS computations used the the standard k-φ and SST turbulence models. Experimental results of Cherry et al provide a reference against which the DES was validated. The SST model has been observed to be overly sensitive to inlet channel aspect ratio. Separation is observed to switch from top to the side wall at higher expansion ratios, while DES predicts separation to stay on the top wall. The recirculating region predicted by the model changes sides even for very small side angles. In a symmetrically--sloped diffuser the model does not predict a symmetric separation at higher side angles. The Reynolds stress models predict symmetric separation, so some of the shortcomings to the SST formulation emerge from the eddy viscosity assumption.

  18. Characterization of an incipiently separated shock wave/turbulent boundary layer interaction

    NASA Astrophysics Data System (ADS)

    Schreyer, A.-M.; Dussauge, J.-P.; Krämer, E.

    2017-03-01

    The turbulence structure in a shock wave/turbulent boundary layer interaction at incipient separation was investigated in order to get insight into turbulence generation and amplification mechanisms in such flow fields. The flow along a two-dimensional 11.5° compression corner was studied experimentally at a Mach number of M=2.53 and with a momentum-thickness Reynolds number of Re_{θ }=5370. From hot-wire boundary layer traverses and surface heat-flux density fluctuation measurements with the fast-response atomic layer thermopile, the turbulence structure and amplification was described. Space-time correlations of the mass-flux fluctuations across the boundary layer and the surface heat-flux density fluctuations were measured to further characterize the development of the turbulence structure across the interaction. The large-scale boundary layer structures are concealed by shock-related effects in the strongly disturbed shock-foot region. Shortly downstream, however, large-scale structures dominate the signal again, just as in the incoming flow. A mechanism explaining this behavior is suggested.

  19. Hemicelluloses prior to aspen chemithermomechanical pulping: pre-extraction, separation, and characterization.

    PubMed

    Liu, Wei; Hou, Qingxi; Mao, Changbin; Yuan, Zhirun; Li, Kecheng

    2012-05-16

    A portion of hemicelluloses and acetic acid can be pre-extracted with dilute sulfuric acid prior to the aspen chemithermomechanical pulp process. The streams collected from the second press-impregnation stage after acid pre-extraction contain a significant amount of acid pre-extracted hemicelluloses. Most of the total sugars obtained from the pressate were xylan, in which xylan was further hydrolyzed to sugar monomers under the acid pre-extraction condition. To fully understand the characteristics of hemicelluloses yielded prior to pulping, the pre-extracted hemicelluloses were separated and characterized by FT-IR, (1)H NMR, and thermogravimetric analysis in this study. Most of the FT-IR bonds from the hemicelluloses agreed well with the other two spectra of birch xylan and CA0050 xylan, except a new absorption at 1734 cm(-1) contributed to acetyl groups. The hemicelluloses obtained from acid pre-extraction began to decompose significantly at about 225 °C, slightly lower in comparison with organosolv and alkaline hemicelluloses reported in the literature.

  20. Characterization of Linearly Separable Boolean Functions: A Graph-Theoretic Perspective.

    PubMed

    Rao, Yanyi; Zhang, Xianda

    2016-04-05

    In this paper, we present a novel approach for studying Boolean function in a graph-theoretic perspective. In particular, we first transform a Boolean function f of n variables into an induced subgraph Hf of the n-dimensional hypercube, and then, we show the properties of linearly separable Boolean functions on the basis of the analysis of the structure of Hf. We define a new class of graphs, called hyperstar, and prove that the induced subgraph Hf of any linearly separable Boolean function f is a hyperstar. The proposal of hyperstar helps us uncover a number of fundamental properties of linearly separable Boolean functions in this paper.

  1. On-line separator for {gamma}-spectroscopic studies

    SciTech Connect

    Popeko, A. G.; Belozerov, A. V.; Chepigin, V. I.; Kabachenko, A. P.; Malyshev, O. N.; Shutov, A. V.; Svirikhin, A. I.; Yeremin, A. V.; Dorvaux, O.; Hauschild, K.; Korichi, A.; Lopez-Martens, A.

    2008-05-12

    We report about R and D of the new separator for spectroscopic studies which we plan to install at the beam of the modernized U400R FLNR cyclotron and which will allow to realize new possibilities of the JINR-IN2P3 collaboration project GABRIELA.

  2. On-line separator for γ-spectroscopic studies

    NASA Astrophysics Data System (ADS)

    Popeko, A. G.; Belozerov, A. V.; Chepigin, V. I.; Dorvaux, O.; Hauschild, K.; Kabachenko, A. P.; Korichi, A.; Lopez-Martens, A.; Malyshev, O. N.; Shutov, A. V.; Svirikhin, A. I.; Yeremin, A. V.

    2008-05-01

    We report about R&D of the new separator for spectroscopic studies which we plan to install at the beam of the modernized U400R FLNR cyclotron and which will allow to realize new possibilities of the JINR-IN2P3 collaboration project GABRIELA [1, 2].

  3. Protein hydrogen exchange studied by the fragment separation method.

    PubMed

    Englander, J J; Rogero, J R; Englander, S W

    1985-05-15

    The potential of hydrogen-exchange studies for providing detailed information on protein structure and structural dynamics has not yet been realized, largely because of the continuing inability to correlate measured exchange behavior with the parts of a protein that generate that behavior. J. Rosa and F. M. Richards (1979, J. Mol. Biol. 133, 399-416) pioneered a promising approach to this problem in which tritium label at exchangeable proton sites can be located by fragmenting the protein, separating the fragments, and measuring the label carried by each fragment. However, severe losses of tritium label during the fragment separation steps have so far rendered the results ambiguous. This paper describes methods that minimize losses of tritium label during the fragment separation steps and correct for losses that do occur so that the label can be unambiguously located and even quantified. Steps that promote adequate fragment isolation are also described.

  4. Molecular Dynamics Study of Polymer Separation Using a Nanofluidic Staircase

    NASA Astrophysics Data System (ADS)

    Phelan, Frederick, Jr.; Forrey, Christopher

    2013-03-01

    The diffusive behavior of isolated polymer chains in a nanofluidic staircase has recently been studied experimentally [Strychalski et al., Macromolecules, 45(3), 1602, (2012); Stavis et al., Lab Chip, 12(19), 1174, (2012)] and by simulation [Phelan et al., in preparation, (2012)]. Chains are observed to exhibit spontaneous 1-D biased diffusion from regions of high to low confinement, without the use of external forces, under conditions where the local confinement lies in either the Odijk or de Gennes regimes. The transport mechanism is that of a Brownian motor, where the polymer free energy is used to generate directed transport using thermal fluctuations and the biased structural features of the device. The nanostaircase has potential for a number of applications in polymer measurement science and transport, an important one of which could be separations. To study this, we examine polymer separation in the nanofluidic staircase using the molecular dynamics simulation software LAMMPS. Length based separations of linear polymers as applicable to DNA separations are the main topic of the study, but the effect of more complex architectures such as branching are also examined.

  5. Characterization of Traveling Wave Ion Mobility Separations in Structures for Lossless Ion Manipulations.

    PubMed

    Hamid, Ahmed M; Ibrahim, Yehia M; Garimella, Sandilya V B; Webb, Ian K; Deng, Liulin; Chen, Tsung-Chi; Anderson, Gordon A; Prost, Spencer A; Norheim, Randolph V; Tolmachev, Aleksey V; Smith, Richard D

    2015-11-17

    We report on the development and characterization of a traveling wave (TW)-based Structures for Lossless Ion Manipulations (TW-SLIM) module for ion mobility separations (IMS). The TW-SLIM module uses parallel arrays of rf electrodes on two closely spaced surfaces for ion confinement, where the rf electrodes are separated by arrays of short electrodes, and using these TWs can be created to drive ion motion. In this initial work, TWs are created by the dynamic application of dc potentials. The capabilities of the TW-SLIM module for efficient ion confinement, lossless ion transport, and ion mobility separations at different rf and TW parameters are reported. The TW-SLIM module is shown to transmit a wide mass range of ions (m/z 200-2500) utilizing a confining rf waveform (∼1 MHz and ∼300 Vp-p) and low TW amplitudes (<20 V). Additionally, the short TW-SLIM module achieved resolutions comparable to existing commercially available low pressure IMS platforms and an ion mobility peak capacity of ∼32 for TW speeds of <210 m/s. TW-SLIM performance was characterized over a wide range of rf and TW parameters and demonstrated robust performance. The combined attributes of the flexible design and low voltage requirements for the TW-SLIM module provide a basis for devices capable of much higher resolution and more complex ion manipulations.

  6. Characterization of Traveling Wave Ion Mobility Separations in Structures for Lossless Ion Manipulations

    DOE PAGES

    Hamid, Ahmed M.; Ibrahim, Yehia M.; Garimella, Venkata BS; ...

    2015-10-28

    We report on the development and characterization of a new traveling wave-based Structure for Lossless Ion Manipulations (TW-SLIM) for ion mobility separations (IMS). The TW-SLIM module uses parallel arrays of rf electrodes on two closely spaced surfaces for ion confinement, where the rf electrodes are separated by arrays of short electrodes, and using these TWs can be created to drive ion motion. In this initial work, TWs are created by the dynamic application of dc potentials. The capabilities of the TW-SLIM module for efficient ion confinement, lossless ion transport, and ion mobility separations at different rf and TW parameters aremore » reported. The TW-SLIM module is shown to transmit a wide mass range of ions (m/z 200–2500) utilizing a confining rf waveform (~1 MHz and ~300 Vp-p) and low TW amplitudes (<20 V). Additionally, the short TW-SLIM module achieved resolutions comparable to existing commercially available low pressure IMS platforms and an ion mobility peak capacity of ~32 for TW speeds of <210 m/s. TW-SLIM performance was characterized over a wide range of rf and TW parameters and demonstrated robust performance. In conclusion, the combined attributes of the flexible design and low voltage requirements for the TW-SLIM module provide a basis for devices capable of much higher resolution and more complex ion manipulations.« less

  7. Characterization of Traveling Wave Ion Mobility Separations in Structures for Lossless Ion Manipulations

    SciTech Connect

    Hamid, Ahmed M.; Ibrahim, Yehia M.; Garimella, Venkata BS; Webb, Ian K.; Deng, Liulin; Chen, Tsung-Chi; Anderson, Gordon A.; Prost, Spencer A.; Norheim, Randolph V.; Tolmachev, Aleksey V.; Smith, Richard D.

    2015-10-28

    We report on the development and characterization of a new traveling wave-based Structure for Lossless Ion Manipulations (TW-SLIM) for ion mobility separations (IMS). The TW-SLIM module uses parallel arrays of rf electrodes on two closely spaced surfaces for ion confinement, where the rf electrodes are separated by arrays of short electrodes, and using these TWs can be created to drive ion motion. In this initial work, TWs are created by the dynamic application of dc potentials. The capabilities of the TW-SLIM module for efficient ion confinement, lossless ion transport, and ion mobility separations at different rf and TW parameters are reported. The TW-SLIM module is shown to transmit a wide mass range of ions (m/z 200–2500) utilizing a confining rf waveform (~1 MHz and ~300 Vp-p) and low TW amplitudes (<20 V). Additionally, the short TW-SLIM module achieved resolutions comparable to existing commercially available low pressure IMS platforms and an ion mobility peak capacity of ~32 for TW speeds of <210 m/s. TW-SLIM performance was characterized over a wide range of rf and TW parameters and demonstrated robust performance. In conclusion, the combined attributes of the flexible design and low voltage requirements for the TW-SLIM module provide a basis for devices capable of much higher resolution and more complex ion manipulations.

  8. Development and characterization of porous silver-incorporated hydroxyapatite ceramic for separation and elimination of microorganisms.

    PubMed

    Yang, Lei; Ning, Xiaoshan; Xiao, Qunfang; Chen, Kexin; Zhou, Heping

    2007-04-01

    A novel filter material for separating and eliminating microorganisms in water and gas was fabricated by incorporating silver ions into porous hydroxyapatite (HA) ceramics prepared by a starch additive technique. The porous ceramics reveal a microstructure of both large and small pores. Microorganism separating and eliminating properties of the porous silver-incorporated HA ceramics (PHA-Ag) were investigated by bacterial and viral filtration tests. The PHA-Ag demonstrated excellent separating and antibacterial effects on Escherichia coli and the mechanisms were studied. Adsorption of bacterial cells to the HA and the barricading effect of small pores contribute to the separating property of PHA-Ag, while the Ag+ ions equip the ceramics with antibacterial property. Furthermore, the PHA-Ag exhibited an observable virus-eliminating property and its probable mechanism was also discussed.

  9. New design studies for TRIUMF's ARIEL High Resolution Separator

    NASA Astrophysics Data System (ADS)

    Maloney, J. A.; Baartman, R.; Marchetto, M.

    2016-06-01

    As part of its new Advanced Rare IsotopE Laboratory (ARIEL), TRIUMF is designing a novel High Resolution Separator (HRS) (Maloney et al., 2015) to separate rare isotopes. The HRS has a 180° bend, separated into two 90° magnetic dipoles, bend radius 1.2 m, with an electrostatic multipole corrector between them. Second order correction comes mainly from the dipole edge curvatures, but is intended to be fine-tuned with a sextupole component and a small octupole component in the multipole. This combination is designed to achieve 1:20,000 resolution for a 3 μm (horizontal) and 6 μm (vertical) emittance. A design for the HRS dipole magnets achieves both radial and integral flatness goals of <10-5. A review of the optical design for the HRS is presented, including the study of limiting factors affecting separation, matching and aberration correction. Field simulations from the OPERA-3D (OPERA) [2] models of the dipole magnets are used in COSY Infinity (COSY) (Berz and Makino, 2005) [3] to find and optimize the transfer maps to 3rd order and study residual nonlinearities to 8th order.

  10. Differential magnetic catch and release: Separation, purification, and characterization of magnetic nanoparticles and particle assemblies

    NASA Astrophysics Data System (ADS)

    Beveridge, Jacob S.

    Magnetic nanoparticles uniquely combine superparamagnetic behavior with dimensions that are smaller than or the same size as molecular analytes. The integration of magnetic nanoparticles with analytical methods has opened new avenues for sensing, purification, and quantitative analysis. Applied magnetic fields can be used to control the motion and properties of magnetic nanoparticles; in analytical chemistry, use of magnetic fields provides methods for manipulating and analyzing species at the molecular level. The ability to use applied magnetic fields to control the motion and properties of magnetic nanoparticles is a tool for manipulating and analyzing species at the molecular level, and has led to applications including analyte handing, chemical sensors, and imaging techniques. This is clearly an area where significant growth and impact in separation science and analysis is expected in the future. In Chapter 1, we describe applications of magnetic nanoparticles to analyte handling, chemical sensors, and imaging techniques. Chapter 2 reports the purification and separation of magnetic nanoparticle mixtures using the technique developed in our lab called differential magnetic catch and release (DMCR). This method applies a variable magnetic flux orthogonal to the flow direction in an open tubular capillary to trap and controllably release magnetic nanoparticles. Magnetic moments of 8, 12, and 17 nm diameter CoFe2O4 nanoparticles are calculated using the applied magnetic flux density and experimentally determined force required to trap 50% of the particle sample. Balancing the relative strengths of the drag and magnetic forces enable separation and purification of magnetic CoFe2 O4 nanoparticle samples with < 20 nm diameters. Samples were characterized by transmission electron microscopy to determine the average size and size dispersity of the sample population. DMCR is further demonstrated to be useful for separation of a magnetic nanoparticle mixture, resulting

  11. Computational Study of Separating Flow in a Planar Subsonic Diffuser

    NASA Technical Reports Server (NTRS)

    DalBello, Teryn; Dippold, Vance, III; Georgiadis, Nicholas J.

    2005-01-01

    A computational study of the separated flow through a 2-D asymmetric subsonic diffuser has been performed. The Wind Computational Fluid Dynamics code is used to predict the separation and reattachment behavior for an incompressible diffuser flow. The diffuser inlet flow is a two-dimensional, turbulent, and fully-developed channel flow with a Reynolds number of 20,000 based on the centerline velocity and the channel height. Wind solutions computed with the Menter SST, Chien k-epsilon, Spalart-Allmaras and Explicit Algebraic Reynolds Stress turbulence models are compared with experimentally measured velocity profiles and skin friction along the upper and lower walls. In addition to the turbulence model study, the effects of grid resolution and use of wall functions were investigated. The grid studies varied the number of grid points across the diffuser and varied the initial wall spacing from y(sup +) = 0.2 to 60. The wall function study assessed the applicability of wall functions for analysis of separated flow. The SST and Explicit Algebraic Stress models provide the best agreement with experimental data, and it is recommended wall functions should only be used with a high level of caution.

  12. MILLIONS OF MULTIPLES: DETECTING AND CHARACTERIZING CLOSE-SEPARATION BINARY SYSTEMS IN SYNOPTIC SKY SURVEYS

    SciTech Connect

    Terziev, Emil; Law, Nicholas M.; Arcavi, Iair; Baranec, Christoph; Bui, Khanh; Dekany, Richard G.; Kulkarni, S. R.; Riddle, Reed; Tendulkar, Shriharsh P.; Bloom, Joshua S.; Burse, Mahesh P.; Chorida, Pravin; Das, H. K.; Punnadi, Sujit; Ramaprakash, A. N.; Kraus, Adam L.; Nugent, Peter; Ofek, Eran O.; Sullivan, Mark

    2013-06-01

    The direct detection of binary systems in wide-field surveys is limited by the size of the stars' point-spread functions (PSFs). A search for elongated objects can find closer companions, but is limited by the precision to which the PSF shape can be calibrated for individual stars. Based on a technique from weak-lensing analysis, we have developed the BinaryFinder algorithm to search for close binaries by using precision measurements of PSF ellipticity across wide-field survey images. We show that the algorithm is capable of reliably detecting binary systems down to Almost-Equal-To 1/5 of the seeing limit, and can directly measure the systems' position angles, separations, and contrast ratios. To verify the algorithm's performance we evaluated 100,000 objects in Palomar Transient Factory (PTF) wide-field-survey data for signs of binarity, and then used the Robo-AO robotic laser adaptive optics system to verify the parameters of 44 high-confidence targets. We show that BinaryFinder correctly predicts the presence of close companions with a <11% false-positive rate, measures the detected binaries' position angles within 1 Degree-Sign to 4 Degree-Sign (depending on signal-to-noise ratio and separation), and separations within 25%, and weakly constrains their contrast ratios. When applied to the full PTF data set, we estimate that BinaryFinder will discover and characterize {approx}450,000 physically associated binary systems with separations <2 arcsec and magnitudes brighter than m{sub R} = 18. New wide-field synoptic surveys with high sensitivity and sub-arcsecond angular resolution, such as LSST, will allow BinaryFinder to reliably detect millions of very faint binary systems with separations as small as 0.1 arcsec.

  13. Millions of Multiples: Detecting and Characterizing Close-separation Binary Systems in Synoptic Sky Surveys

    NASA Astrophysics Data System (ADS)

    Terziev, Emil; Law, Nicholas M.; Arcavi, Iair; Baranec, Christoph; Bloom, Joshua S.; Bui, Khanh; Burse, Mahesh P.; Chorida, Pravin; Das, H. K.; Dekany, Richard G.; Kraus, Adam L.; Kulkarni, S. R.; Nugent, Peter; Ofek, Eran O.; Punnadi, Sujit; Ramaprakash, A. N.; Riddle, Reed; Sullivan, Mark; Tendulkar, Shriharsh P.

    2013-06-01

    The direct detection of binary systems in wide-field surveys is limited by the size of the stars' point-spread functions (PSFs). A search for elongated objects can find closer companions, but is limited by the precision to which the PSF shape can be calibrated for individual stars. Based on a technique from weak-lensing analysis, we have developed the BinaryFinder algorithm to search for close binaries by using precision measurements of PSF ellipticity across wide-field survey images. We show that the algorithm is capable of reliably detecting binary systems down to ≈1/5 of the seeing limit, and can directly measure the systems' position angles, separations, and contrast ratios. To verify the algorithm's performance we evaluated 100,000 objects in Palomar Transient Factory (PTF) wide-field-survey data for signs of binarity, and then used the Robo-AO robotic laser adaptive optics system to verify the parameters of 44 high-confidence targets. We show that BinaryFinder correctly predicts the presence of close companions with a <11% false-positive rate, measures the detected binaries' position angles within 1° to 4° (depending on signal-to-noise ratio and separation), and separations within 25%, and weakly constrains their contrast ratios. When applied to the full PTF data set, we estimate that BinaryFinder will discover and characterize ~450,000 physically associated binary systems with separations <2 arcsec and magnitudes brighter than mR = 18. New wide-field synoptic surveys with high sensitivity and sub-arcsecond angular resolution, such as LSST, will allow BinaryFinder to reliably detect millions of very faint binary systems with separations as small as 0.1 arcsec.

  14. Characterization of micro- and nanophase separation of dentin bonding agents by stereoscopy and atomic force microscopy.

    PubMed

    Toledano, Manuel; Yamauti, Monica; Osorio, Estrella; Monticelli, Francesca; Osorio, Raquel

    2012-04-01

    The aim was to study the effect of solvents on the phase separation of four commercial dental adhesives. Four materials were tested: Clearfil™ SE Bond (CSE), Clearfil Protect Bond (CPB), Clearfil S3 Bond (CS3), and One-Up Bond F Plus (OUB). Distilled water or ethanol was used as a solvent (30 vol%) for microphase separation studies, by stereoscopy. For nanophase images, the mixtures were formulated with two different solvent concentrations (2.5 versus 5 vol%) and observed by atomic force microscopy. Images were analyzed by using MacBiophotonics ImageJ to measure the area of bright domains. Macrophase separations, identified as a loss of clarity, were only observed after mixing the adhesives with water. Nanophase separations were detected with all adhesive combinations. The area of bright domains ranged from 132 to 1,145 nm² for CSE, from 15 to 285 nm² for CPB, from 149 to 380 nm² for CS3, and from 26 to 157 nm² for OUB. In water-resins mixtures, CPB was the most homogeneous and OUB showed the most heterogeneous phase formation. In ethanol-resin mixtures, CSE attained the most homogeneous structure and OUB showed the most heterogeneous phase. Addition of 5 vol% ethanol to resins decreased the nanophase separation when compared with the control materials.

  15. Novel nanocomposite Kevlar fabric membranes: Fabrication characterization, and performance in oil/water separation

    NASA Astrophysics Data System (ADS)

    Karimnezhad, Hanieh; Rajabi, Laleh; Salehi, Ehsan; Derakhshan, Ali Ashraf; Azimi, Sara

    2014-02-01

    Nanocomposite membranes with hydrophilic surface were fabricated for separation of oil (n-hexane) from oil/water emulsion. Three different nanomaterials namely, para-aminobenzoate alumoxane (PAB-A), boehmite-epoxide and polycitrate alumoxane (PC-A) were coated on the Kevlar fabric (support), according to a three-step dip-coating protocol. FTIR, SEM, TEM, UV/vis spectrophotometer, and wettability analyses were used to characterize the composite membranes. The three coating layers interacted chemically with one another and also physically with the Kevlar fabric. Water uptake measurements indicated that the membrane is a hydrophilic one. SEM and TEM analyses showed the smooth surface of the composite membrane and three-dimensional dendrimeric hyper-branched structure of (PC-A), respectively. A dead-end filtration setup was applied to test the membranes performance under natural gravity force. Effect of pH as an important variable affecting separation process was investigated with the neutral pH provided the optimum condition for the separation. Oil rejection and permeate fluxes were also monitored. The optimum flux and rejection obtained, were 7392 (Lm-2 h-1) and 89.06% at pH 7, respectively. Fouling occurred as a gel layer on the membrane surface. The deposited oil droplets on the surface of the membrane were successfully washed away with satisfactory permeate flux recovery (FRR = 88.88% at neutral pH), using hot distilled water and acidic solution as eluents.

  16. Hydrodynamic size-based separation and characterization of protein aggregates from total cell lysates

    PubMed Central

    Tanase, Maya; Zolla, Valerio; Clement, Cristina C; Borghi, Francesco; Urbanska, Aleksandra M; Rodriguez-Navarro, Jose Antonio; Roda, Barbara; Zattoni, Andrea; Reschiglian, Pierluigi; Cuervo, Ana Maria; Santambrogio, Laura

    2016-01-01

    Herein we describe a protocol that uses hollow-fiber flow field-flow fractionation (FFF) coupled with multiangle light scattering (MALS) for hydrodynamic size-based separation and characterization of complex protein aggregates. The fractionation method, which requires 1.5 h to run, was successfully modified from the analysis of protein aggregates, as found in simple protein mixtures, to complex aggregates, as found in total cell lysates. In contrast to other related methods (filter assay, analytical ultracentrifugation, gel electrophoresis and size-exclusion chromatography), hollow-fiber flow FFF coupled with MALS allows a flow-based fractionation of highly purified protein aggregates and simultaneous measurement of their molecular weight, r.m.s. radius and molecular conformation (e.g., round, rod-shaped, compact or relaxed). The polyethersulfone hollow fibers used, which have a 0.8-mm inner diameter, allow separation of as little as 20 μg of total cell lysates. In addition, the ability to run the samples in different denaturing and nondenaturing buffer allows defining true aggregates from artifacts, which can form during sample preparation. The protocol was set up using Paraquat-induced carbonylation, a model that induces protein aggregation in cultured cells. This technique will advance the biochemical, proteomic and biophysical characterization of molecular-weight aggregates associated with protein mutations, as found in many CNS degenerative diseases, or chronic oxidative stress, as found in aging, and chronic metabolic and inflammatory conditions. PMID:25521790

  17. Heterogeneous glycoform separation by process chromatography: I: Monomer purification and characterization.

    PubMed

    Li, Yi; Xu, Xuankuo; Shupe, Alan; Yang, Rong; Bai, Kevin; Das, Tapan; Borys, Michael C; Li, Zheng Jian

    2015-07-24

    Fc fusion proteins with high and low sialylation were purified and separated by preparative ion-exchange and hydrophobic interaction chromatography. Heterogeneity in sialylation and glycosylation led to variation in surface charge and hydrophobicity, and resulted in multiple distinct glycoform populations in response to various purification conditions. Monomer with high sialic acid content has higher surface charge and adsorbs stronger to ion-exchange resin, while the less sialylated monomer interacts more favorably with hydrophobic resin. Extensive biophysical characterization was carried out for purified monomers at different level of sialylation. In general, different monomeric glycoforms have different surface charge and hydrophobicity, different thermal stability, and different aggregation propensity. The surface charge corresponds well with sialic acid content, as evidenced by electrophoresis, N-link domain analysis, and zeta potential results. The sialylation also contributes to minor modification of protein size, molecular mass and tertiary structure. Notably, fluorescence emission spectra and thermal transition became less distinguishable when the monomers containing low and high sialic acid were prepared in high ionic strength solution. Such finding reiterates the fact that the electrostatic forces, which are largely dependent on sialic acid content of protein, plays a dominant role in many intra- and inter-molecular interactions. Overall, the characterization data agreed well with separation behaviors and provided valuable insight to control of glycoform profile in purification process.

  18. Separation, characterization and anticancer activities of a sulfated polysaccharide from Undaria pinnatifida.

    PubMed

    Han, Yun; Wu, Jun; Liu, Tingting; Hu, Youdong; Zheng, Qiusheng; Wang, Binsheng; Lin, Haiyan; Li, Xia

    2016-02-01

    The purpose of this paper was to investigate separation, characterization and anticancer activities of a sulfated polysaccharide (SPUP) from Undaria pinnatifida. Firstly, polysaccharide from U. pinnatifida was separated by DEAE-52 cellulose and Sephacryl S-400 column chromatography. As results, SPUP was obtained with the yield of 19.42%. Then, SPUP was characterized using chemical analysis, gas chromatography, size-exclusion HPLC chromatography, UV-vis spectra and FT-IR spectrum. The content of total sugar, uronic acid, protein and sulfate radical were 80.48%, 3.21%, 7.12% and 29.14%, respectively. SPUP was a heteropolysaccharide composed of fucose, glucose and galactose in a molar percentage of 27.15:19.34:53.51 with molecular weight of 97.9 kDa. Finally, the strongly against breast cancer activity of SPUP was confirmed by DMBA-induced breast cancer rats model. AS results, SPUP can significantly restrain breast abnormal enlargement, prolong tumor latency and reduced tumor incidence. Immunomodulatory activity and regulating abnormal sex hormones level might contribute to its anticancer activities.

  19. Separability studies of construction and demolition waste recycled sand.

    PubMed

    Ulsen, Carina; Kahn, Henrique; Hawlitschek, Gustav; Masini, Eldon A; Angulo, Sérgio C

    2013-03-01

    The quality of recycled aggregates from construction and demolition waste (CDW) is strictly related to the content of porous and low strength phases, and specifically to the patches of cement that remain attached to the surface of natural aggregates. This phase increases water absorption and compromises the consistency and strength of concrete made from recycled aggregates. Mineral processing has been applied to CDW recycling to remove the patches of adhered cement paste on coarse recycled aggregates. The recycled fine fraction is usually disregarded due to its high content of porous phases despite representing around 50% of the total waste. This paper focus on laboratory mineral separability studies for removing particles with a high content of cement paste from natural fine aggregate particles (quartz/feldspars). The procedure achieved processing of CDW by tertiary impact crushing to produce sand, followed by sieving and density and magnetic separability studies. The attained results confirmed that both methods were effective in reducing cement paste content and producing significant mass recovery (80% for density concentration and 60% for magnetic separation). The production of recycled sand contributes to the sustainability of the construction environment by reducing both the consumption of raw materials and disposal of CDW, particularly in large Brazilian centers with a low quantity of sand and increasing costs of this material due to long transportation distances.

  20. Chromatographic Studies of Protein-Based Chiral Separations.

    PubMed

    Bi, Cong; Zheng, Xiwei; Azaria, Shiden; Beeram, Sandya; Li, Zhao; Hage, David S

    2016-09-01

    The development of separation methods for the analysis and resolution of chiral drugs and solutes has been an area of ongoing interest in pharmaceutical research. The use of proteins as chiral binding agents in high-performance liquid chromatography (HPLC) has been an approach that has received particular attention in such work. This report provides an overview of proteins that have been used as binding agents to create chiral stationary phases (CSPs) and in the use of chromatographic methods to study these materials and protein-based chiral separations. The supports and methods that have been employed to prepare protein-based CSPs will also be discussed and compared. Specific types of CSPs that are considered include those that employ serum transport proteins (e.g., human serum albumin, bovine serum albumin, and alpha1-acid glycoprotein), enzymes (e.g., penicillin G acylase, cellobiohydrolases, and α-chymotrypsin) or other types of proteins (e.g., ovomucoid, antibodies, and avidin or streptavidin). The properties and applications for each type of protein and CSP will also be discussed in terms of their use in chromatography and chiral separations.

  1. Chromatographic Studies of Protein-Based Chiral Separations

    PubMed Central

    Bi, Cong; Zheng, Xiwei; Azaria, Shiden; Beeram, Sandya; Li, Zhao; Hage, David S.

    2016-01-01

    The development of separation methods for the analysis and resolution of chiral drugs and solutes has been an area of ongoing interest in pharmaceutical research. The use of proteins as chiral binding agents in high-performance liquid chromatography (HPLC) has been an approach that has received particular attention in such work. This report provides an overview of proteins that have been used as binding agents to create chiral stationary phases (CSPs) and in the use of chromatographic methods to study these materials and protein-based chiral separations. The supports and methods that have been employed to prepare protein-based CSPs will also be discussed and compared. Specific types of CSPs that are considered include those that employ serum transport proteins (e.g., human serum albumin, bovine serum albumin, and alpha1-acid glycoprotein), enzymes (e.g., penicillin G acylase, cellobiohydrolases, and α-chymotrypsin) or other types of proteins (e.g., ovomucoid, antibodies, and avidin or streptavidin). The properties and applications for each type of protein and CSP will also be discussed in terms of their use in chromatography and chiral separations. PMID:28344977

  2. Brachytherapy source characterization for improved dose calculations using primary and scatter dose separation.

    PubMed

    Russell, Kellie R; Tedgren, Asa K Carlsson; Ahnesjö, Anders

    2005-09-01

    In brachytherapy, tissue heterogeneities, source shielding, and finite patient/phantom extensions affect both the primary and scatter dose distributions. The primary dose is, due to the short range of secondary electrons, dependent only on the distribution of material located on the ray line between the source and dose deposition site. The scatter dose depends on both the direct irradiation pattern and the distribution of material in a large volume surrounding the point of interest, i.e., a much larger volume must be included in calculations to integrate many small dose contributions. It is therefore of interest to consider different methods for the primary and the scatter dose calculation to improve calculation accuracy with limited computer resources. The algorithms in present clinical use ignore these effects causing systematic dose errors in brachytherapy treatment planning. In this work we review a primary and scatter dose separation formalism (PSS) for brachytherapy source characterization to support separate calculation of the primary and scatter dose contributions. We show how the resulting source characterization data can be used to drive more accurate dose calculations using collapsed cone superposition for scatter dose calculations. Two types of source characterization data paths are used: a direct Monte Carlo simulation in water phantoms with subsequent parameterization of the results, and an alternative data path built on processing of AAPM TG43 formatted data to provide similar parameter sets. The latter path is motivated of the large amounts of data already existing in the TG43 format. We demonstrate the PSS methods using both data paths for a clinical 192Ir source. Results are shown for two geometries: a finite but homogeneous water phantom, and a half-slab consisting of water and air. The dose distributions are compared to results from full Monte Carlo simulations and we show significant improvement in scatter dose calculations when the collapsed

  3. An experimental study of mushroom shaped stall cells. [on finite wings with separated flow

    NASA Technical Reports Server (NTRS)

    Winkelmann, A. E.

    1982-01-01

    Surface patterns characterized by a pair of counter-rotating swirls have been observed in connection with the conduction of surface flow visualization experiments involving test geometries with separated flows. An example of this phenomenon occurring on a finite wing with trailing edge stall has been referred to by Winkelmann and Barlow (1980) as 'mushroom shaped'. A description is presented of a collection of experimental results which show or suggest the occurrence of mushroom shaped stall cells on a variety of test geometries. Investigations conducted with finite wings, airfoil models, and flat plates are considered, and attention is given to studies involving the use of bluff models, investigations of shock induced boundary layer separation, and mushroom shaped patterns observed in a number of miscellaneous cases. It is concluded that the mushroom shaped stall cell appears commonly in separated flow regions.

  4. Thermodynamic Studies to Support Actinide/Lanthanide Separations

    SciTech Connect

    Rao, Linfeng

    2015-09-01

    This milestone report summarizes the data obtained in FY15 on the complexation of HEDTA with Np(V) and U(VI) in a temperature range from 25 to 70°C. The results show the effect of temperature on the chemical speciation of Np(V) and U(VI) in the modified TALSPEAK Process, and help to evaluate the effectiveness of the process when the operation envelope (e.g., temperature) varies. Eventually, the results from this study will help to achieve a better control of the separation process based on the HEDTA/HEH[EHP] combination.

  5. Characterization of microparticle separation utilizing electrokinesis within an electrodeless dielectrophoresis chip.

    PubMed

    Chiou, Chi-Han; Pan, Jia-Cheng; Chien, Liang-Ju; Lin, Yu-Ying; Lin, Jr-Lung

    2013-02-27

    This study demonstrated the feasibility of utilizing electrokinesis in an electrodeless dielectrophoresis chip to separate and concentrate microparticles such as biosamples. Numerical simulations and experimental observations were facilitated to investigate the phenomena of electrokinetics, i.e., electroosmosis, dielectrophoresis, and electrothermosis. Moreover, the proposed operating mode can be used to simultaneously convey microparticles through a microfluidic device by using electroosmotic flow, eliminating the need for an additional micropump. These results not only revealed that the directions of fluids could be controlled with a forward/backward electroosmotic flow but also categorized the optimum separating parameters for various microparticle sizes (0.5, 1.0 and 2.0 μm). Separation of microparticles can be achieved by tuning driving frequencies at a specific electric potential (90 Vpp·cm(-1)). Certainly, the device can be designed as a single automated device that carries out multiple functions such as transportation, separation, and detection for the realization of the envisioned Lab-on-a-Chip idea.

  6. Uranium dioxide in Fe(III)-containing ionic liquids with DMSO: Dissolution, separation, and structural characterization

    NASA Astrophysics Data System (ADS)

    Yao, Aining; Chu, Taiwei

    2016-11-01

    UO2 can be successfully dissolved in imidazolium-based Fe(III)-containing ionic liquids (ILs) with the help of DMSO. Spectroscopic studies and X-ray diffraction show that UO2Cl42- is the principal product. The dissolved uranyl species can be easily separated from the ILs via a combination of crystallization and solvent extraction. Moreover, even if 15.2 wt% of the rare-earth elements of Sm, Eu, and Gd, compared with the total amount of uranium and the rare-earth elements, exist in the IL, only uranium-containing crystals would be selectively formed and separated from the system. The solvents of acetone and acetonitrile could be used to separate the rare-earth elements from uranium in the IL with the help of imidazolium chloride. Considering the complete process from the dissolution of UO2 and some rare-earth oxides to the separation of uranium and rare-earth elements in the IL, the facile approach is promising for the spent nuclear fuel reprocessing.

  7. Parametric Studies of Flow Separation using Air Injection

    NASA Technical Reports Server (NTRS)

    Zhang, Wei

    2004-01-01

    Boundary Layer separation causes the airfoil to stall and therefore imposes dramatic performance degradation on the airfoil. In recent years, flow separation control has been one of the active research areas in the field of aerodynamics due to its promising performance improvements on the lifting device. These active flow separation control techniques include steady and unsteady air injection as well as suction on the airfoil surface etc. This paper will be focusing on the steady and unsteady air injection on the airfoil. Although wind tunnel experiments revealed that the performance improvements on the airfoil using injection techniques, the details of how the key variables such as air injection slot geometry and air injection angle etc impact the effectiveness of flow separation control via air injection has not been studied. A parametric study of both steady and unsteady air injection active flow control will be the main objective for this summer. For steady injection, the key variables include the slot geometry, orientation, spacing, air injection velocity as well as the injection angle. For unsteady injection, the injection frequency will also be investigated. Key metrics such as lift coefficient, drag coefficient, total pressure loss and total injection mass will be used to measure the effectiveness of the control technique. A design of experiments using the Box-Behnken Design is set up in order to determine how each of the variables affects each of the key metrics. Design of experiment is used so that the number of experimental runs will be at minimum and still be able to predict which variables are the key contributors to the responses. The experiments will then be conducted in the 1ft by 1ft wind tunnel according to the design of experiment settings. The data obtained from the experiments will be imported into JMP, statistical software, to generate sets of response surface equations which represent the statistical empirical model for each of the metrics as

  8. Hyper-X Stage Separation Trajectory Validation Studies

    NASA Technical Reports Server (NTRS)

    Tartabini, Paul V.; Bose, David M.; McMinn, John D.; Martin, John G.; Strovers, Brian K.

    2003-01-01

    An independent twelve degree-of-freedom simulation of the X-43A separation trajectory was created with the Program to Optimize Simulated trajectories (POST II). This simulation modeled the multi-body dynamics of the X-43A and its booster and included the effect of two pyrotechnically actuated pistons used to push the vehicles apart as well as aerodynamic interaction forces and moments between the two vehicles. The simulation was developed to validate trajectory studies conducted with a 14 degree-of-freedom simulation created early in the program using the Automatic Dynamic Analysis of Mechanics Systems (ADAMS) simulation software. The POST simulation was less detailed than the official ADAMS-based simulation used by the Project, but was simpler, more concise and ran faster, while providing similar results. The increase in speed provided by the POST simulation provided the Project with an alternate analysis tool. This tool was ideal for performing separation control logic trade studies that required the running of numerous Monte Carlo trajectories.

  9. Characterization of thermoplastic microfiltration chip for the separation of blood plasma from human blood.

    PubMed

    Chen, Pin-Chuan; Chen, Chih-Chun; Young, Kung-Chia

    2016-09-01

    In this study, we developed a fully thermoplastic microfiltration chip for the separation of blood plasma from human blood. Spiral microchannels were manufactured on a PMMA substrate using a micromilling machine, and a commercial polycarbonate membrane was bonded between two thermoplastic substrates. To achieve an excellent bonding between the commercial membrane and the thermoplastic substrates, we used a two-step injection and curing procedure of UV adhesive into a ring-shaped structure around the microchannel to efficiently prevent leakage during blood filtration. We performed multiple filtration experiments using human blood to compare the influence of three factors on separation efficiency: hematocrit level (40%, 23.2%, and 10.9%), membrane pore size (5 μm, 2 μm, and 1 μm), and flow rate (0.02 ml/min, 0.06 ml/min, 0.1 ml/min). To prevent hemolysis, the pressure within the microchannel was kept below 0.5 bars throughout all filtration experiments. The experimental results clearly demonstrated the following: (1) The proposed microfiltration chip is able to separate white blood cells and red blood cells from whole human blood with a separation efficiency that exceeds 95%; (2) no leakage occurred during any of the experiments, thereby demonstrating the effectiveness of bonding a commercial membrane with a thermoplastic substrate using UV adhesive in a ring-shaped structure; (3) separation efficiency can be increased by using a membrane with smaller pore size, by using diluted blood with lower hematocrit, or by injecting blood into the microfiltration chip at a lower flow rate.

  10. Separating and characterizing functional alkane degraders from crude-oil-contaminated sites via magnetic nanoparticle-mediated isolation.

    PubMed

    Wang, Xinzi; Zhao, Xiaohui; Li, Hanbing; Jia, Jianli; Liu, Yueqiao; Ejenavi, Odafe; Ding, Aizhong; Sun, Yujiao; Zhang, Dayi

    Uncultivable microorganisms account for over 99% of all species on the planet, but their functions are yet not well characterized. Though many cultivable degraders for n-alkanes have been intensively investigated, the roles of functional n-alkane degraders remain hidden in the natural environment. This study introduces the novel magnetic nanoparticle-mediated isolation (MMI) technology in Nigerian soils and successfully separates functional microbes belonging to the families Oxalobacteraceae and Moraxellaceae, which are dominant and responsible for alkane metabolism in situ. The alkR-type n-alkane monooxygenase genes, instead of alkA- or alkP-type, were the key functional genes involved in the n-alkane degradation process. Further physiological investigation via a BIOLOG PM plate revealed some carbon (Tween 20, Tween 40 and Tween 80) and nitrogen (tyramine, l-glutamine and d-aspartic acid) sources promoting microbial respiration and n-alkane degradation. With further addition of promoter carbon or nitrogen sources, the separated functional alkane degraders significantly improved n-alkane biodegradation rates. This suggests that MMI is a promising technology for separating functional microbes from complex microbiota, with deeper insight into their ecological functions and influencing factors. The technique also broadens the application of the BIOLOG PM plate for physiological research on functional yet uncultivable microorganisms.

  11. Synthesis, pervaporation and gas separation studies of polyaniline blends

    SciTech Connect

    Huang, S.C.; Conklin, J.A.; Su, T.M.

    1995-12-01

    Membranes have been successfully produced from blends of polyaniline/polyacrylic acid and polyaniline/polyimide. The uniqueness of these membranes is the incorporation of {open_quotes}polymer dopants{close_quotes} in polyaniline. Conductivity measurements show that polyacrylic acid dopes the polyaniline. Pervaporation of water and water/acetic acid mixtures were performed using polyaniline and its polyacrylic acid blend. An improved flux over the polyaniline base form is observed. Polyaniline/polyimide blends were synthesized for gas permeability studies. These blends combine improved thermal stability relative to polyaniline with greater gas selectivity relative to polyimide. The blend shows an increase in permeability for all gases studied over both, polyaniline base and polyimide, while maintaining comparable separation factors.

  12. Experimental study of two separating turbulent boundary layers

    NASA Technical Reports Server (NTRS)

    Nagabushana, K. A.; Simpson, R. L.; Agarwal, N. K.

    1987-01-01

    A detailed study of two strong adverse pressure gradient flows, one with a free-stream velocity of 35 m/sec, at throat (producing a Re sub theta of 27000 at detachment) and another with free-stream velocity of 22 m/sec, at throat (producing a Re sub theta of 19000 at detachment) is presented. In these examples flows separate slowly and reattach very rapidly over a very short distance in a streamwise direction. In the backflow region, there appears to be a semi-logarithmically flat region in the streamwise fluctuating velocity component, u', which spreads over a definite range of y/delta. In power spectra, the flow variables phi sub upsilon upsilon (kappa sub 1 delta)/ -uv bar sub max vs. kappa sub 1 delta forms a unique set of scaling parameters for adverse pressure gradient flows. Experimental results show good agreement with previous studies.

  13. Numerical Study of Control of Flow Separation Over a Ramp with Nanosecond Plasma Actuator

    NASA Astrophysics Data System (ADS)

    Zheng, J. G.; Khoo, B. C.; Cui, Y. D.; Zhao, Z. J.; Li, J.

    2016-06-01

    The nanosecond plasma discharge actuator driven by high voltage pulse with typical rise and decay time of several to tens of nanoseconds is emerging as a promising active flow control means in recent years and is being studied intensively. The characterization study reveals that the discharge induced shock wave propagates through ambient air and introduces highly transient perturbation to the flow. On the other hand, the residual heat remaining in the discharge volume may trigger the instability of external flow. In this study, this type of actuator is used to suppress flow separation over a ramp model. Numerical simulation is carried out to investigate the interaction of the discharge induced disturbance with the external flow. It is found that the flow separation region over the ramp can be reduced significantly. Our work may provide some insights into the understanding of the control mechanism of nanosecond pulse actuator.

  14. Model system studies with a phase separated membrane bioreactor

    NASA Technical Reports Server (NTRS)

    Petersen, G. R.; Seshan, P. K.; Dunlop, Eric H.

    1989-01-01

    The operation and evaluation of a bioreactor designed for high intensity oxygen transfer in a microgravity environment is described. The reactor itself consists of a zero headspace liquid phase separated from the air supply by a long length of silicone rubber tubing through which the oxygen diffuses in and the carbon dioxide diffuses out. Mass transfer studies show that the oxygen is film diffusion controlled both externally and internally to the tubing and not by diffusion across the tube walls. Methods of upgrading the design to eliminate these resistances are proposed. Cell growth was obtained in the fermenter using Saccharomyces cerevisiae showing that this concept is capable of sustaining cell growth in the terrestial simulation.

  15. Phase separated membrane bioreactor - Results from model system studies

    NASA Technical Reports Server (NTRS)

    Petersen, G. R.; Seshan, P. K.; Dunlop, E. H.

    1989-01-01

    The operation and evaluation of a bioreactor designed for high intensity oxygen transfer in a microgravity environment is described. The reactor itself consists of a zero headspace liquid phase separated from the air supply by a long length of silicone rubber tubing through which the oxygen diffuses in and the carbon dioxide diffuses out. Mass transfer studies show that the oxygen is film diffusion controlled both externally and internally to the tubing and not by diffusion across the tube walls. Methods of upgrading the design to eliminate these resistances are proposed. Cell growth was obtained in the fermenter using Saccharomyces cerevisiae showing that this concept is capable of sustaining cell growth in the terrestrial simulation.

  16. Phase separated membrane bioreactor: results from model system studies.

    PubMed

    Petersen, G R; Seshan, P K; Dunlop, E H

    1989-01-01

    The operation and evaluation of a bioreactor designed for high intensity oxygen transfer in a microgravity environment is described. The reactor itself consists of a zero headspace liquid phase separated from the air supply by a long length of silicone rubber tubing through which the oxygen diffuses in and the carbon dioxide diffuses out. Mass transfer studies show that the oxygen is film diffusion controlled both externally and internally to the tubing and not by diffusion across the tube walls. Methods of upgrading the design to eliminate these resistances are proposed. Cell growth was obtained in the fermenter using Saccharomyces cerevisiae showing that this concept is capable of sustaining cell growth in the terrestrial [correction of terrestial] simulation.

  17. Feasibility studies for separation processes using environmentally sensitive hydrogels

    SciTech Connect

    Sassi, A.P.; Blanch, H.W.; Prausnitz, J.M.

    1994-12-01

    Temperature- and pH-sensitive hydrogels can be used to separate or concentrate proteins from dilute solution. Two possible separation processes are discussed here. Experimental partitioning data are used to compare the efficiencies of neutral, weakly acidic, weakly basic, and polyampholytic poly-N-isopropylacrylamide copolymer gels for separating cytochrome c from ovalbumin. For each process, attention is given to the influence of the solute partition coefficient and swelling equilibria on process efficiency.

  18. The optical properties of single-walled carbon nanotubes: Separation, characterization, and measurement in suspension

    NASA Astrophysics Data System (ADS)

    Russo, Richard M.

    The one dimensional structure of single-walled carbon nanotubes (SWNTs) gives rise to optical phenomena that differ from bulk materials. This dissertation studies the separation of SWNTs dissolved in aqueous media using surfactant molecules, and the measurement of their intrinsic optical properties including absorption and emission. The SWNTs were separated from the bundled form using mechanical processing techniques such as sonication and centrifugation. A processing study, which isolated the effects of sonication frequency, sonication power, and centrifugation speed, was performed to determine the factors that lead to the best separation. The results of this study suggest that the suspensions are a mixture of individual tubes and small bundles. Prior determinations of intrinsic nanotube properties based on the assumption of isolated nanotubes will have to be revisited. The transient absorption spectrum was measured for the S11 subband region using monochromatic pump excitation at wavelengths corresponding to S22 subband transitions, where the exciting pump fluence was sufficient to create many excitons on a single nanotube. The transient decay kinetics followed a linear dependence that was proportional to 1/ t on a log-log scale with a slope of -0.5, which is consistent with the diffusion limited recombination of excitons in one dimension. This result suggests that the decay of photoexcitations in nanotubes is initially governed by two-body kinetics, which becomes a one-body process only in the long time limit. Our work refutes the one-electron model for the excited state relaxation of nanotubes proposed by others. When the transient decay was studied as a function of the initial exciton population, the diffusion coefficient was found to be a different constant value at each initial population. Local thermalization of the surrounding medium may cause this difference, as thermal relaxation occurs on a time scale that is longer than that of exciton recombination in

  19. Molecular dynamics study of phase separation in fluids with chemical reactions.

    PubMed

    Krishnan, Raishma; Puri, Sanjay

    2015-11-01

    We present results from the first d=3 molecular dynamics (MD) study of phase-separating fluid mixtures (AB) with simple chemical reactions (A⇌B). We focus on the case where the rates of forward and backward reactions are equal. The chemical reactions compete with segregation, and the coarsening system settles into a steady-state mesoscale morphology. However, hydrodynamic effects destroy the lamellar morphology which characterizes the diffusive case. This has important consequences for the phase-separating structure, which we study in detail. In particular, the equilibrium length scale (ℓ(eq)) in the steady state suggests a power-law dependence on the reaction rate ε:ℓ(eq)∼ε(-θ) with θ≃1.0.

  20. Enhanced Landfill Mining case study: Innovative separation techniques

    NASA Astrophysics Data System (ADS)

    Cuyvers, Lars; Moerenhout, Tim; Helsen, Stefan; Van de Wiele, Katrien; Behets, Tom; Umans, Luk; Wille, Eddy

    2014-05-01

    In 2011, a corporate vision on Enhanced Landfill Mining (ELFM)1 was approved by the OVAM Board of directors, which resulted in an operational programme over the period 2011-2015. OVAM (Public Waste Agency of Flanders) is the competent authority in charge of waste, Sustainable Materials Management (SMM) and contaminated soil management in Flanders. The introduction of the ELFM concept needs to be related with the concept of SMM and the broader shift to a circular economy. Within the concept of ELFM, landfills are no longer considered to be a final and static situation, but a dynamic part of the materials cycle. The main goal of this research programme is to develop a comprehensive policy on resource management to deal with the issue of former landfills. In order to investigate the opportunities of ELFM, the OVAM is applying a three step approach including mapping, surveying and mining of these former landfills. As a result of the mapping part over 2,000 landfill sites, that will need to be dealt with, were revealed. The valorisation potential of ELFM could be assigned to different goals, according to the R³P-concept : Recycling of Materials, Recovery of Energy, Reclamation of Land and Protection of drinking water supply. . On behalf of the OVAM, ECOREM was assigned to follow-up a pilot case executed on a former landfill, located in Zuienkerke, Flanders. Within this case study some technical tests were carried out on the excavated waste material to investigate the possibilities for a waste to resource conversion. The performance of both on site and off site techniques were evaluated. These testings also contribute to the mapping part of OVAM's research programme on ELFM and reveal more information on the composition of former landfills dating from different era's. In order to recover as many materials as possible, five contractors were assigned to perform separation tests on the bulk material from the Zuienkerke landfill. All used techniques were described

  1. Synthesis and characterization of a porous and hydrophobic cellulose-based composite for efficient and fast oil-water separation.

    PubMed

    Wang, Xiangyun; Xu, Shimei; Tan, Yun; Du, Juan; Wang, Jide

    2016-04-20

    Oily wastewater is generated in diverse industrial processes, and its treatment has become crucial due to increasing environmental concerns. Herein, silanized cellulose was prepared by sol-gel reaction between microcrystalline cellulose (MCC) and hexadecyltrimethoxysilane (HDTMS) using for oil-water separation. The silanized cellulose was characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and thermal gravimetric analysis (TGA). A higher mass ratio of HDTMS to MCC made silanized cellulose become looser, and showed lower water absorbency. The silanized cellulose exhibited specific separation performance towards vegetable oil-water mixture (not for mineral oil-water mixture) with separation efficiency of 99.93%. Moreover, the separation was fast with a water flux of 4628.5Lm(-2)h(-1). The separation efficiency still remained at 99.77% even after recycling for 10 times.

  2. Characterizing uncertainties for quantifying bathymetry change between time-separated multibeam echo-sounder surveys

    NASA Astrophysics Data System (ADS)

    Schmitt, Thierry; Mitchell, Neil C.; Ramsay, A. Tony S.

    2008-05-01

    Changes of bathymetry derived from multibeam sonars are useful for quantifying the effects of many sedimentary, tectonic and volcanic processes, but depth changes also require an assessment of their uncertainty. Here, we outline and illustrate a simple technique that aims both to quantify uncertainties and to help reveal the spatial character of errors. An area of immobile seafloor is mapped in each survey, providing a common 'benchmark'. Each survey dataset over the benchmark is filtered with a simple moving-averaging window and depth differences between the two surveys are collated to derive a difference histogram. The procedure is repeated using different length-scales of filtering. By plotting the variability of the differences versus the length-scale of the filter, the different effects of spatially uncorrelated and correlated noise can be deduced. The former causes variability to decrease systematically as predicted by the Central Limit Theorem, whereas the remaining variability not predicted by the Central Limit Theorem then represents the effect of spatially correlated noise. Calculations made separately for different beams can reveal whether problems are due to heave, roll, etc., which affect inner and outer beams differently. We show how the results can be applied to create a map of uncertainties, which can be used to remove insignificant data from the bathymetric change map. We illustrate the technique by characterizing changes in nearshore bed morphology over one annual cycle using data from a subtidal bay, bedrock headland and a banner sand bank in the Bristol Channel UK.

  3. Surgery and parental separation as potential risk factors for abnormal eating attitudes-longitudinal study.

    PubMed

    Bachar, Eytan; Stein, Daniel; Canetti, Laura; Gur, Eitan

    2008-11-01

    Due to the susceptibility of eating disorders (ED) to stressful life events, we wanted to examine longitudinally whether two childhood adversities: (1) surgery and (2) parental separation, will affect abnormal eating attitudes in adolescents. Consecutively for 4 years, the eating attitude test (EAT-26) and the eating disorder inventory-2 (EDI-2) questionnaires were administered to students from grades 7th through 10th and 8th through 11th. Multilevel analysis revealed that parental separation and oral or cosmetic dermatologic surgeries were significantly correlated with EAT-26 and EDI-2 scores throughout the 4 years of the study. Post-hoc interpretation suggests a connection between (A) chirurgic intervention in the oral cavity and problematic eating attitudes, and (B) cosmetic dermatologic surgery and greater awareness to body appearance-a feature which might characterize adolescents who are prone to develop ED.

  4. A study of the separation of particles from gases

    SciTech Connect

    Stevens, G.L. II; Masudi, H.

    1995-03-01

    Cyclones are the simplest and most reliable means of particles and gas separation. They also function as a method of air pollution control and as a cost efficient way of doing so. These basic machines have been in use for many years, and based on advances in technology, cyclones have now been designed for specific applications and conditions. These applications are restricted by inherent properties of the construction of the cyclone, and the materials being separated within the cyclone.

  5. Human small-intestinal β-galactosidases. Separation and characterization of three forms of an acid β-galactosidase

    PubMed Central

    Asp, Nils-Georg

    1971-01-01

    1. An acid β-galactosidase, optimum pH4.0–4.5, in the human small-intestinal mucosa was separated and characterized. 2. Autolysis of mucosal homogenates at acid pH inactivated the lactase and hetero β-galactosidase; the total activity of the acid β-galactosidase was only slightly depleted, but a greater proportion of the enzyme was solubilized by this treatment. 3. Separation on a Sephadex G-200 column revealed that the acid β-galactosidase could occur in at least three different forms, probably representing monomer, dimer and octamer or polymer of the enzyme. 4. The properties of the different forms of the acid β-galactosidase were studied with regard to pH optimum, Km, rate of hydrolysis of different substrates, and sensitivity to p-chloromercuribenzoate and tris as inhibitors. All these properties were the same for the different forms of the enzyme. 5. The acid β-galactosidase hydrolyses lactose as well as hetero β-galactosides and contributes to the lactase activity of intestinal biopsies also when measured at pH 6. This enzyme may therefore be responsible for a considerable part of the residual lactase activity found in lactose-intolerant patients. PMID:5117032

  6. Functional characterization of human thymocyte subpopulations separated by density gradient centrifugation.

    PubMed Central

    Lederman, H M; Lee, J W; Cohen, A; Gelfand, E W

    1984-01-01

    A bovine serum albumin gradient was used to separate two populations of human thymocytes--a minority population (8%) of large thymocytes (LT) and a majority population (92%) of small thymocytes (ST). Fifty per cent of LT cells were in the S, G2 or M phases of the cell cycle compared to 5% of ST cells and 15% of unfractionated thymocytes. LT cells proliferated in response to T cell mitogens and included all of the T colony precursor cells (TCPC). In contrast, ST cells proliferated with mitogens only in the presence of added T cell growth factors and contained none of the thymocyte TCPC. ST cells neither helped nor suppressed the function of LT cells in any assay. This separation technique has provided a rapid method for isolating functionally distinct thymic lymphocyte subpopulations and permitted a further definition of the TCPC in the human thymus. Furthermore it should prove useful in studies of thymocytes at different stages of the cell cycle. PMID:6607793

  7. Mixing quality characterization in separation process tanks. Part 2: Solids-suspension

    SciTech Connect

    Hassan, N.M.

    1995-12-31

    Nuclear criticality safety in Separations canyon facilities is maintained primarily by control of the concentration of fissile materials in process equipment. Confidence in the attainment of this goal is clearly dependent upon how a measurement of solids concentration from the local sampling technique relates to concentrations elsewhere in the vessel, and on the quality of mixing prevailing under operating conditions. Clarification was therefore needed of the relationship between the local concentration of solids found at the present regular sampling point, and the prevailing maximum and average throughout the vessel. An experimental study was performed to document the quality of mixing for dilute solids suspension in an aqueous phase in baffled, paddle-agitated, cylindrical tanks used in Separations canyon facilities. Measurements were made for those variables that are capable of adjustments in the full scale: namely impeller speed, height of the total liquid, and number of impellers on the shaft. Appropriate total liquid levels and minimum impeller speed for just complete suspension of solids were established for the full scale operation. The effects of particle size distribution and mean concentration of solids are demonstrated, and conditions under which the regular single sampling point gives results comparable to the average of variously placed measurements around the vessel are identified. Solids distribution in the radial and axial directions were examined and some recurring trends have been identified. A simplified mass balance and coil impediment calculations indicate the need for new sampling techniques to explore the region around and between the impellers.

  8. Analytical and preparative separation of PEGylated lysozyme for the characterization of chromatography media.

    PubMed

    Moosmann, Anna; Christel, Jessica; Boettinger, Heiner; Mueller, Egbert

    2010-01-08

    The effect of PEGylation on cation exchange chromatography was studied with poly(ethylene glycol) of different chain lengths (5kDa, 10kDa and 30kDa) using lysozyme as a model system. A stable binding via reduction of a Schiff base was formed during random PEGylation on lysine residues with methoxy-PEG-aldehyde. A purification method for PEGylated proteins using cation exchange chromatography was developed, and different isoforms of mono-PEGylated lysozyme were isolated. TSKgel SP-5PW and Toyopearl GigaCap S-650M showed the best performance of all tested cation exchange resins, and the separation of PEGylated lysozyme could be also scaled up to semi-preparative level. Size-exclusion chromatography, SDS-PAGE and MALDI-TOF mass spectrometry were used for analysis. Separated mono-PEGylated lysozyme of different sizes was used to determine dynamic binding capacities (DBC) and selectivity of cation exchange chromatography resins. An optimization of binding conditions resulted in a more than 20-fold increase of DBC for Toyopearl GigaCap S-650M with 30kDa mono-PEGylated lysozyme.

  9. Synthesis and characterization of novel stationary phases for small scale liquid chromatographic separations of proteins and nanoparticles

    NASA Astrophysics Data System (ADS)

    Hutanu, Daniela

    The emerging field of nanotechnology strictly requires the micro-scaling of the available separation technology and the design of novel devices for separations of molecules of interest. The separation of proteins and nanoparticles is challenging due to their relatively large size, non-specific adherence to surfaces and instability in many solvents. This dissertation presents the synthesis and characterization of novel stationary phases for use in separations of proteins or nanoparticles in both capillary and microchip formats. In order to separate blood proteins with high specificity, a DNA aptamer selected for alpha-thrombin was employed as an affinity component of the stationary phases. Silica surfaces and organic monoliths were modified with the aptamer via an azlactone linkage and have demonstrated highly efficient separations of thrombin from a mixture in the microscale. The high efficiency of the protein separation (HETP = 276 mum, RS = 1.7) is comparable with macroscale results using antibodies as the affinity factor. Novel hybrid inorganic-organic polysilsesquioxane stationary phases were synthesized by way of surfactant templated polymerization of bridged alcoxy-silyl ethane monomers, in presence of sodium hydroxide. The novel materials were successful in size exclusion separation of polystyrene standards with molecular diameters of 0.3-2.4 nm. A hybrid inorganic-organic polysilsesquioxane sorbent also proved useful for small scale separations of triphenyl phosphine protected gold nanoparticles, based on a sorptive mechanism instead of a size exclusion mechanism. Polysilsesquioxanes were easily synthesized in-situ inside fused silica capillary columns and PMMA microchip channels in order to facilitate integration with a micro-reactor. The novel stationary phases proved efficient for separation of proteins and nanoparticles in the micro-scale format and can further be utilized for online purification and separation of these difficult compounds.

  10. SIPCAn (Separation, Isolation, Purification, Characterization, and Analysis): A One-Term, Integrated Project for the Undergraduate Organic Laboratory

    ERIC Educational Resources Information Center

    Dintzner, Matthew R.; Kinzie, Charles R.; Pulkrabek, Kimberly A.; Arena, Anthony F.

    2011-01-01

    SIPCAn, an acronym for separation, isolation, purification, characterization, and analysis, is presented as a one-term, integrated project for the first-term undergraduate organic laboratory course. Students are assigned two mixtures of unknown organic compounds--a mixture of two liquid compounds and a mixture of two solid compounds--at the…

  11. Groundwater flux characterization using distributed temperature sensing: Separating advection from thermal conduction

    NASA Astrophysics Data System (ADS)

    Liu, G.; Knobbe, S.; Butler, J. J., Jr.

    2015-12-01

    Direct measurement of groundwater flux is difficult to obtain in the field so hydrogeologists often use easily-detectable environmental tracers, such as heat or chemicals, as an indirect way to characterize flux. Previously, we developed a groundwater flux characterization (GFC) probe by using distributed temperature sensing (DTS) to monitor the temperature responses to active heating in a well. The temperature responses were consistent with the hydraulic conductivity profiles determined at the same location, and provided high-resolution information (approx. 1.5 cm) about vertical variations in horizontal flux through the screen. One of the key assumptions in the previous GFC approach was that the vertical variations in the thermal conductivity of the aquifer materials near the well are negligible, so that the temperature differences with depth are primarily a result of groundwater flux instead of thermal conduction. Although this assumption is likely valid for wells constructed with an artificial filter pack, it might become questionable for wells with natural filter packs (such as the wells constructed by direct push where the sediments are allowed to directly collapse onto the well screen). In this work, we develop a new procedure for separating advection from thermal conduction during GFC measurement. In addition to the normal open-screen GFC profiling, an impermeable sleeve was used so that heating tests could be performed without advective flow entering the well. The heating tests under sleeved conditions were primarily controlled by the thermal conduction around the well, and therefore could be used to remove the impact of thermal conduction from the normal GFC results obtained under open-screen conditions. This new procedure was tested in a laboratory sandbox, where a series of open-screen and sleeved GFC tests were performed under different flow rates. Results indicated that for the tested range of rates (Darcy velocity 0 - 0.78 m/d), the relation between

  12. Experimental Study of Unsteady Separation in a Laminar Boundary Layer

    NASA Astrophysics Data System (ADS)

    Bonacci, Andrew; Lang, Amy; Wahidi, Redha; Santos, Leo

    2016-11-01

    Separation, caused by an adverse pressure gradient, can be a major problem to aircraft. Reversing flow occurs in separated regions and an investigation of how this backflow forms is of interest due to the fact that this could be used as a means of initiating flow control. Specifically, backflow can bristle shark scales which may be linked to a passive, flow actuated separation control mechanism. An experiment was conducted in a water tunnel to replicate separation, with a focus on the reversing flow development near the wall within a laminar boundary layer. Using a rotating cylinder, an adverse pressure gradient was induced creating a separated region over a flat plate. In this experiment the boundary layer grows to sizes great enough that the scale of the flow is increased, making it more measurable to DPIV. In the future, this research can be utilized to better understand flow control mechanisms such as those enabled by shark skin. Funding from Army Research Office and NSF REU site Grant EEC 1358991 is greatly appreciated.

  13. Compact high resolution isobar separator for study of exotic decays

    NASA Astrophysics Data System (ADS)

    Shchepunov, V.; Piechaczek, A.; Carter, H. K.; Batchelder, J. C.; Zganjar, E. F.

    2009-05-01

    A compact isobar separator, based on the Multi-Pass-Time-of-Flight (MTOF) principle, is developed. A mass resolving power (MRP) of 110,000 (FWHM) is achieved as spectrometer with a transmission of 50 - 80%. The transverse beam acceptance and the energy acceptance are 42 π mm mrad and about ± 2.5%. Operated as a separator, molecules of N2 and CO with δM/M = 1/2500 or 10.433 MeV were separated with a Bradbury Nielsen gate. In that mode of operation, the MRP (FWHM) is about 40,000 after 120 laps. To inject radioactive ion beams into the separator, and to further improve its MRP, cooler and buncher RF quadrupoles were designed^1 and tested. A bunch width of 30 ns at 1% of the peak height (FWHM = 9 ns) and a transmission in DC mode of 75 -- 80 % were achieved. With such bunch parameters, MRPs of ˜ 400,000 (FWHM) are expected for the MTOF separator. At HRIBF, it will provide pure samples of exotic nuclides around ^100Sn, of neutron deficient rare-earth nuclei and of neutron-rich nuclei. Incidental measurements of mass differences will determine Qβ values with accuracies of ˜ 1%. ^1 V. Shchepunov and V. Kozlovskiy et al., to be published

  14. Source separation of household waste: A case study in China

    SciTech Connect

    Zhuang Ying; Wu Songwei; Wang Yunlong; Wu Weixiang Chen Yingxu

    2008-07-01

    A pilot program concerning source separation of household waste was launched in Hangzhou, capital city of Zhejiang province, China. Detailed investigations on the composition and properties of household waste in the experimental communities revealed that high water content and high percentage of food waste are the main limiting factors in the recovery of recyclables, especially paper from household waste, and the main contributors to the high cost and low efficiency of waste disposal. On the basis of the investigation, a novel source separation method, according to which household waste was classified as food waste, dry waste and harmful waste, was proposed and performed in four selected communities. In addition, a corresponding household waste management system that involves all stakeholders, a recovery system and a mechanical dehydration system for food waste were constituted to promote source separation activity. Performances and the questionnaire survey results showed that the active support and investment of a real estate company and a community residential committee play important roles in enhancing public participation and awareness of the importance of waste source separation. In comparison with the conventional mixed collection and transportation system of household waste, the established source separation and management system is cost-effective. It could be extended to the entire city and used by other cities in China as a source of reference.

  15. Thermomorphic phase separation in ionic liquid-organic liquid systems--conductivity and spectroscopic characterization.

    PubMed

    Riisager, Anders; Fehrmann, Rasmus; Berg, Rolf W; van Hal, Roy; Wasserscheid, Peter

    2005-08-21

    Electrical conductivity, FT-Raman and NMR measurements are demonstrated as useful tools to probe and determine phase behavior of thermomorphic ionic liquid-organic liquid systems. To illustrate the methods, consecutive conductivity measurements of a thermomorphic methoxyethoxyethyl-imidazolium ionic liquid/1-hexanol system are performed in the temperature interval 25-80 degrees C using a specially constructed double-electrode cell. In addition, FT-Raman and 1H-NMR spectroscopic studies performed on the phase-separable system in the same temperature interval confirm the mutual solubility of the components in the system, the liquid-liquid equilibrium phase diagram of the binary mixture, and signify the importance of hydrogen bonding between the ionic liquid and the hydroxyl group of the alcohol.

  16. Quantitative characterizations of ultrashort echo (UTE) images for supporting air-bone separation in the head

    NASA Astrophysics Data System (ADS)

    Hsu, Shu-Hui; Cao, Yue; Lawrence, Theodore S.; Tsien, Christina; Feng, Mary; Grodzki, David M.; Balter, James M.

    2015-04-01

    Accurate separation of air and bone is critical for creating synthetic CT from MRI to support Radiation Oncology workflow. This study compares two different ultrashort echo-time sequences in the separation of air from bone, and evaluates post-processing methods that correct intensity nonuniformity of images and account for intensity gradients at tissue boundaries to improve this discriminatory power. CT and MRI scans were acquired on 12 patients under an institution review board-approved prospective protocol. The two MRI sequences tested were ultra-short TE imaging using 3D radial acquisition (UTE), and using pointwise encoding time reduction with radial acquisition (PETRA). Gradient nonlinearity correction was applied to both MR image volumes after acquisition. MRI intensity nonuniformity was corrected by vendor-provided normalization methods, and then further corrected using the N4itk algorithm. To overcome the intensity-gradient at air-tissue boundaries, spatial dilations, from 0 to 4 mm, were applied to threshold-defined air regions from MR images. Receiver operating characteristic (ROC) analyses, by comparing predicted (defined by MR images) versus ‘true’ regions of air and bone (defined by CT images), were performed with and without residual bias field correction and local spatial expansion. The post-processing corrections increased the areas under the ROC curves (AUC) from 0.944 ± 0.012 to 0.976 ± 0.003 for UTE images, and from 0.850 ± 0.022 to 0.887 ± 0.012 for PETRA images, compared to without corrections. When expanding the threshold-defined air volumes, as expected, sensitivity of air identification decreased with an increase in specificity of bone discrimination, but in a non-linear fashion. A 1 mm air mask expansion yielded AUC increases of 1 and 4% for UTE and PETRA images, respectively. UTE images had significantly greater discriminatory power in separating air from bone than PETRA images. Post-processing strategies improved the

  17. Traumatic separation of epiphyses. An experimental study in rats.

    PubMed

    Gomes, L S; Volpon, J B; Goncalves, R P

    1988-11-01

    Four types of physeal fracture-separations, defined by the Salter-Harris classification, were created experimentally in the proximal physis of the right tibia of immature rats. The four types are: Type I, pure epiphyseal separation; Type II, separation of the epiphysis with a metaphyseal fracture; Type III, partial epiphyseal separation with a vertical fracture of the epiphysis; and Type IV, vertical epiphyseal and metaphyseal fractures. A sham operation performed on the left tibia served as the control. The animals were killed at various intervals up to 25 days after the operation. The findings were assessed by roentgenographic, histologic, and vessel injection methods. For Types I and II morphometric analyses were also performed. The influence of various types of lesions on the growth rate and the healing process was documented. For Types I and II lesions there was a transitory growth arrest and an increased thickening of the zone of hypertrophic cells. The alterations regressed after Day 15, and by day 25, a nearly normal plate was seen. For Type III lesions an angular deformity of the tibia occurred that increased with time. For Type IV lesions, a step-off developed on the articular surface that became more severe with time. Early vascular anastomoses between the epiphysis and the metaphysis led to the formation of bone bridges in Type III and Type IV lesions.

  18. Separation and characterization of barley (Hordeum vulgare L.) hordeins by free zone capillary electrophoresis.

    PubMed

    Lookhart, G L; Bean, S R; Jones, B L

    1999-06-01

    Extraction conditions, separation conditions, and capillary rinsing protocols were optimized for the separation of barley hordeins by free zone capillary electrophoresis. Stable hordein extracts were obtained with a single 5 min extraction after the albumins and globulins were removed. Hordeins had to be reduced for optimal resolution. Optimum separation conditions for hordein separations were 100 mM phosphate-glycine buffer containing 20% acetonitrile and 0.05% hydroxypropylmethylcellulose. The addition of zwitterionic sulfobetaine detergents containing hydrocarbon tails of eight and ten carbons slightly improved the resolution of the separations, but not enough to warrant their use on a routine basis. The migration positions of the hordein subclasses were determined by two- dimensional reversed-phase high-performance liquid chromatography x free zone capillary electrophoresis mapping. The hordein subclasses formed clusters similar to those of wheat gliadins. Separation-to-separation repeatability was good, with migration time relative standard deviations < 1% for a 15-run period. For routine discrimination of cultivars, a 2 min post-separation rinse with 500 mM acetic acid was necessary to prevent protein build-up on the capillary walls. An example of successfully differentiating barley cultivars using this technique is shown.

  19. Liquid effluent study characterization data

    SciTech Connect

    Not Available

    1990-05-01

    During the development of the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement), public comments were received regarding reduction of the discharge of liquid effluents into the soil column. As a result, the US Department of Energy (DOE), with concurrence of the Washington State Department of Ecology (WSDE)and the US Environmental Protection Agency (EPA), committed to a special project designed to document the discharge history and the charter of Hanford Site liquid discharges. The results of this project will be used in determining the need for additional waste stream analysis, and/or to negotiate additional milestones pertaining to such discharges in the Tri-Party Agreement. Wastestream sampling data collected prior to October 1989 were reported in the Waste Stream Characterization Report. Preliminary Stream-specific Reports were prepared which evaluated that data and proposed dangerous waste designations for each stream. This document contains the wastestream sampling and analysis data collected as part of the liquid effluent study. Data contained in this report were obtained from samples collected from October 1989 through March 1990. Information is presented on the wastestreams that have been sampled, the parameters analyzed, and the dates and times at which the samples were collected. This information will be evaluated in the final Stream-Specific Reports. 9 refs., 4 tabs.

  20. New peak broadening parameter for the characterization of separation capability in capillary electrophoresis.

    PubMed

    Sursyakova, Viktoria V; Rubaylo, Anatoly I

    2015-02-01

    The influence of separation conditions on peak broadening is usually estimated by the number of theoretical plates. Using the data available in literature and experimental data, it is shown that in pressure-assisted capillary electrophoresis the plate number is not directly related to the separation capability of conditions used. The experiments at different electrolyte flow velocities demonstrate that a higher plate number (the best separation efficiency) can be obtained with a lower peak resolution. Since ions are separated by electrophoresis due to the difference in electrophoretic mobilities, the peak width in terms of electrophoretic mobility is suggested as a new peak broadening parameter describing the separation capability of the conditions used. The parameter can be calculated using the tailing factor and the temporal peak width at 5% of the peak height. A simple equation for the resolution calculation is derived using the parameter. The advantage of the peak width in terms of mobility over other parameters is shown. The new parameter is recommended to be used not only in pressure-assisted capillary electrophoresis but also in general capillary electrophoresis when in a number of runs the virtual separative migration distance and separation capability of the conditions used change widely.

  1. Atmospheric-pressure plasma activation and surface characterization on polyethylene membrane separator

    NASA Astrophysics Data System (ADS)

    Tseng, Yu-Chien; Li, Hsiao-Ling; Huang, Chun

    2017-01-01

    The surface hydrophilic activation of a polyethylene membrane separator was achieved using an atmospheric-pressure plasma jet. The surface of the atmospheric-pressure-plasma-treated membrane separator was found to be highly hydrophilic realized by adjusting the plasma power input. The variations in membrane separator chemical structure were confirmed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Chemical analysis showed newly formed carbonyl-containing groups and high surface concentrations of oxygen-containing species on the atmospheric-pressure-plasma-treated polymeric separator surface. It also showed that surface hydrophilicity primarily increased from the polar component after atmospheric-pressure plasma treatment. The surface and pore structures of the polyethylene membrane separator were examined by scanning electron microscopy, revealing a slight alteration in the pore structure. As a result of the incorporation of polar functionalities by atmospheric-pressure plasma activation, the electrolyte uptake and electrochemical impedance of the atmospheric-pressure-plasma-treated membrane separator improved. The investigational results show that the separator surface can be controlled by atmospheric-pressure plasma surface treatment to tailor the hydrophilicity and enhance the electrochemical performance of lithium ion batteries.

  2. Using a Microscale Approach to Rapidly Separate and Characterize Three Photosynthetic Pigment Species from Fern

    ERIC Educational Resources Information Center

    Ayudhya, Theppawut Israsena Na; Posey, Frederick T.; Tyus, Jessica C.; Dingra, Nin N.

    2015-01-01

    A rapid separation of three photosynthetic pigments (chlorophyll "a" and "b" and xanthophyll) from fern ("Polystichum acrostichoides") is described using microscale solvent extraction and traditional thin layer chromatography that minimizes use of harmful chemicals and lengthy procedures. The experiment introduces…

  3. Synthesis, characterization and photocatalytic activity of magnetically separable hexagonal Ni/ZnO nanostructure.

    PubMed

    Senapati, Samarpita; Srivastava, Suneel K; Singh, Shiv B

    2012-10-21

    The hexagonal zinc oxide coated nickel (Ni/ZnO) nanostructure photocatalyst has successfully been prepared by the reduction of nickel chloride hexahydrate using hydrazine hydrate through the solvothermal process at 140 °C followed by surface modification of the product by the reflux method at 110 °C for 1 h. The X-ray diffraction (XRD) pattern showed that the 'as prepared' sample consists of face centered cubic Ni and hexagonal wurtzite ZnO without any traces of impurity. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images confirmed the formation of nickel nanoparticles under solvothermal conditions. These nickel nanoparticles, when subjected to reflux, formed the hexagonal zinc oxide coated nickel nanostructure. Fourier transform infrared (FTIR) spectra, photoluminescence (PL) and Raman studies also confirmed the presence of zinc oxide in the hybrid nanostructure. The growth mechanism for the development of the hexagonal zinc oxide coated nickel (Ni/ZnO) nanostructure has also been proposed. The appearance of the hysteresis loop, in the as-prepared Ni/ZnO hybrid nanostructure, demonstrated its ferromagnetic character at room temperature. The hexagonal Ni/ZnO nanostructure also acts as an efficient photocatalyst in the degradation of methylene blue under ultraviolet light irradiation. It is observed that the catalytic efficiency of the hybrid nanocatalyst is better compared to pure zinc oxide. Most importantly, the Ni/ZnO catalyst could also be easily separated, simply by applying an external magnetic field, and reused.

  4. Synthesis and characterization of new biopolymeric microcapsules containing DEHPA-TOPO extractants for separation of uranium from phosphoric acid solutions.

    PubMed

    Outokesh, Mohammad; Tayyebi, Ahmad; Khanchi, Alireza; Grayeli, Fatemeh; Bagheri, Ghodrat

    2011-01-01

    A novel microcapsule adsorbent for separation of uranium from phosphoric acid solutions was developed by immobilizing the di(2-ethylhexyl) phosphoric acid-trioctyl phosphine oxide extractants in the polymeric matrix of calcium alginate. Physical characterization of the microcapsules was accomplished by scanning electron microscopy and thermogravimetric techniques. Equilibrium experiments revealed that both ion exchange and solvent extraction mechanisms were involved in the adsorption of [Formula: see text] ions, but the latter prevailed in a wider range of acid concentration. According to the results of kinetics study, at low acidity level, the rate controlling step was slow chemical reaction of [Formula: see text] ions with the microdroplets of extractant, whereas it changed to intraparticle diffusion at higher acid concentration. The study also attempted identification of the diffusion paths of the ions within the microcapsules, and the mechanism of change of mass transfer rate during the uptake process. The prepared microcapsules preserved their entire capacity after three cycles of adsorption, and their breakthrough behaviour was well fitted by a new formula derived from shrinking core model.

  5. An experimental study of separated flow on a finite wing

    NASA Technical Reports Server (NTRS)

    Winkelmann, A. E.

    1981-01-01

    The flow field associated with the formation of a mushroom shaped trailing edge stall cell on a low-aspect-ratio (AR = 4.0) wing was investigated in a series of low speed wind tunnel tests (Reynolds number based on 15.2 cm chord = 480,000). Flow field surveys of the separation bubble and wake of a partially stalled and fully stalled wing were completed using a hot-wire probe, a split-film probe, and a directional sensitive pressure probe. A new color video display technique was developed to display the flow field survey data. Photographs were obtained of surface oil flow patterns and smoke flow visualization

  6. Nitrogen Trifluoride-Based Fluoride- Volatility Separations Process: Initial Studies

    SciTech Connect

    McNamara, Bruce K.; Scheele, Randall D.; Casella, Andrew M.; Kozelisky, Anne E.

    2011-09-28

    This document describes the results of our investigations on the potential use of nitrogen trifluoride as the fluorinating and oxidizing agent in fluoride volatility-based used nuclear fuel reprocessing. The conceptual process uses differences in reaction temperatures between nitrogen trifluoride and fuel constituents that produce volatile fluorides to achieve separations and recover valuable constituents. We provide results from our thermodynamic evaluations, thermo-analytical experiments, kinetic models, and provide a preliminary process flowsheet. The evaluations found that nitrogen trifluoride can effectively produce volatile fluorides at different temperatures dependent on the fuel constituent.

  7. Dirac equation in Kerr-NUT-(A)dS spacetimes: Intrinsic characterization of separability in all dimensions

    NASA Astrophysics Data System (ADS)

    Cariglia, Marco; Krtouš, Pavel; Kubizňák, David

    2011-07-01

    We intrinsically characterize separability of the Dirac equation in Kerr-NUT-(A)dS spacetimes in all dimensions. Namely, we explicitly demonstrate that, in such spacetimes, there exists a complete set of first-order mutually commuting operators, one of which is the Dirac operator, that allows for common eigenfunctions which can be found in a separated form and correspond precisely to the general solution of the Dirac equation found by Oota and Yasui [Phys. Lett. BPYLBAJ0370-2693 659, 688 (2008)10.1016/j.physletb.2007.11.057]. Since all the operators in the set can be generated from the principal conformal Killing-Yano tensor, this establishes the (up-to-now) missing link among the existence of hidden symmetry, presence of a complete set of commuting operators, and separability of the Dirac equation in these spacetimes.

  8. A Scoping Review of Qualitative Studies about Children Experiencing Parental Separation

    ERIC Educational Resources Information Center

    Birnbaum, Rachel; Saini, Michael

    2013-01-01

    This article explores a scoping review of qualitative studies about children's experiences and feelings during times of parental separation. The purpose of the review was to explore children's feelings and attitudes about their parents' separation and how their voices are heard during times of parental separation. The scoping review examined 44…

  9. Synthesis, characterization and photocatalytic activity of magnetically separable hexagonal Ni/ZnO nanostructure

    NASA Astrophysics Data System (ADS)

    Senapati, Samarpita; Srivastava, Suneel K.; Singh, Shiv B.

    2012-09-01

    The hexagonal zinc oxide coated nickel (Ni/ZnO) nanostructure photocatalyst has successfully been prepared by the reduction of nickel chloride hexahydrate using hydrazine hydrate through the solvothermal process at 140 °C followed by surface modification of the product by the reflux method at 110 °C for 1 h. The X-ray diffraction (XRD) pattern showed that the `as prepared' sample consists of face centered cubic Ni and hexagonal wurtzite ZnO without any traces of impurity. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images confirmed the formation of nickel nanoparticles under solvothermal conditions. These nickel nanoparticles, when subjected to reflux, formed the hexagonal zinc oxide coated nickel nanostructure. Fourier transform infrared (FTIR) spectra, photoluminescence (PL) and Raman studies also confirmed the presence of zinc oxide in the hybrid nanostructure. The growth mechanism for the development of the hexagonal zinc oxide coated nickel (Ni/ZnO) nanostructure has also been proposed. The appearance of the hysteresis loop, in the as-prepared Ni/ZnO hybrid nanostructure, demonstrated its ferromagnetic character at room temperature. The hexagonal Ni/ZnO nanostructure also acts as an efficient photocatalyst in the degradation of methylene blue under ultraviolet light irradiation. It is observed that the catalytic efficiency of the hybrid nanocatalyst is better compared to pure zinc oxide. Most importantly, the Ni/ZnO catalyst could also be easily separated, simply by applying an external magnetic field, and reused.The hexagonal zinc oxide coated nickel (Ni/ZnO) nanostructure photocatalyst has successfully been prepared by the reduction of nickel chloride hexahydrate using hydrazine hydrate through the solvothermal process at 140 °C followed by surface modification of the product by the reflux method at 110 °C for 1 h. The X-ray diffraction (XRD) pattern showed that the `as prepared' sample consists of face

  10. Test Procedures for Characterizing, Evaluating, and Managing Separator Materials used in Secondary Alkaline Batteries

    NASA Technical Reports Server (NTRS)

    Guasp, Edwin; Manzo, Michelle A.

    1997-01-01

    Secondary alkaline batteries, such as nickel-cadmium and silver-zinc, are commonly used for aerospace applications. The uniform evaluation and comparison of separator properties for these systems is dependent upon the measurement techniques. This manual presents a series of standard test procedures that can be used to evaluate, compare, and select separator materials for use in alkaline batteries. Detailed test procedures evaluating the following characteristics are included in this manual: physical measurements of thickness and area weight, dimensional stability measurements, electrolyte retention, resistivity, permeability as measured via bubble pressure, surface evaluation via SEM, chemical stability, and tensile strength.

  11. A review of exosome separation techniques and characterization of B16-F10 mouse melanoma exosomes with AF4-UV-MALS-DLS-TEM.

    PubMed

    Petersen, Kevin E; Manangon, Eliana; Hood, Joshua L; Wickline, Samuel A; Fernandez, Diego P; Johnson, William P; Gale, Bruce K

    2014-12-01

    Exosomes participate in cancer metastasis, but studying them presents unique challenges as a result of their small size and purification difficulties. Asymmetrical field flow fractionation with in-line ultraviolet absorbance, dynamic light scattering, and multi-angle light scattering was applied to the size separation and characterization of non-labeled B16-F10 exosomes from an aggressive mouse melanoma cell culture line. Fractions were collected and further analyzed using batch mode dynamic light scattering, transmission electron microscopy and compared with known size standards. Fractogram peak positions and computed radii show good agreement between samples and across fractions. Ultraviolet absorbance fractograms in combination with transmission electron micrographs were able to resolve subtle heterogeneity of vesicle retention times between separate batches of B16-F10 exosomes collected several weeks apart. Further, asymmetrical field flow fractionation also effectively separated B16-F10 exosomes into vesicle subpopulations by size. Overall, the flow field flow fractionation instrument combined with multiple detectors was able to rapidly characterize and separate exosomes to a degree not previously demonstrated. These approaches have the potential to facilitate a greater understanding of exosome function by subtype, as well as ultimately allow for "label-free" isolation of large scale clinical exosomes for the purpose of developing future exosome-based diagnostics and therapeutics.

  12. Fenton-like degradation of Methylene Blue using paper mill sludge-derived magnetically separable heterogeneous catalyst: Characterization and mechanism.

    PubMed

    Zhou, Guoqiang; Chen, Ziwen; Fang, Fei; He, Yuefeng; Sun, Haili; Shi, Huixiang

    2015-09-01

    For the paper industry, the disposal and management of the yielded sludge are a considerable challenge. In our work, the paper mill sludge-derived magnetically separable heterogeneous catalyst (PMS-Fe-380) was prepared easily through a facile synthesis method. The morphology and structure of PMS-Fe-380 were fully characterized by means of X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and Brunauer-Emmet-Teller analysis. The catalytic activity of PMS-Fe-380 was evaluated by degradation of Methylene Blue (MB). The reusability and stability of PMS-Fe-380 were evaluated in five repeated runs, which suggested that PMS-Fe-380 manifested excellent stability of catalytic activity. Moreover, leaching tests indicated that the leached iron is negligible (<0.5mg/L). This study provides an alternative environmentally friendly reuse method for paper mill sludge and a novel catalyst PMS-Fe-380 that can be considered as a promising heterogeneous Fenton-like catalyst.

  13. Characterization of induced struvite formation from source-separated urine using seawater and brine as magnesium sources.

    PubMed

    Liu, Bianxia; Giannis, Apostolos; Zhang, Jiefeng; Chang, Victor W-C; Wang, Jing-Yuan

    2013-11-01

    Struvite (MgNH4PO4·6H2O) precipitation is widely used for nutrient recovery from source-separated urine in view of limited natural resources. Spontaneous struvite formation depletes the magnesium in hydrolyzed urine so that additional magnesium source is required to produce induced struvite for P-recovery. The present study investigated the morphology and purity of induced struvite crystals obtained from hydrolyzed urine by using seawater and desalination brine as low cost magnesium sources. The results demonstrated that both seawater and brine were effective magnesium sources to recover phosphorus from hydrolyzed urine. Crystals obtained from synthetic and real urine were revealed that the morphology was feather and coffin shape, respectively. Structural characterization of the precipitates confirmed that crystallized struvite was the main product. However, co-precipitates magnesium calcite and calcite were observed when seawater was added into synthetic and real urine, respectively. It was found that the presence of calcium in the magnesium sources could compromise struvite purity. Higher struvite purity could be obtained with higher Mg/Ca ratio in the magnesium source. Comparative analysis indicated that seawater and brine had similar effect on the crystallized struvite purity.

  14. Characterization and Control of Separated Entrance Flow in a Branched Channel

    NASA Astrophysics Data System (ADS)

    Peterson, C. J.; Vukasinovic, B.; Glezer, A.

    2015-11-01

    The evolution of the flow downstream of the inlet of a rectangular channel that is branched along the entire span of the side wall of a primary channel of the same height is investigated experimentally in an air facility. Of particular interest is the formation and scaling of a separated flow domain downstream of the entrance plane into the secondary channel and its interaction with the flow surfaces at speeds up to M = 0 . 4 . The separation is actively controlled using a spanwise array of fluidic actuators on the primary channel's surface upstream of the inlet plane of the secondary duct. The effects of the actuation on the evolution of the separation and attachment of the vorticity layer between upstream surface of the primary duct and the surface of the secondary duct downstream of the branched inlet in the presence of a strong confined adverse pressure gradient are investigated using particle image velocimetry coupled with detailed static surface pressure distributions. The effects of the controlled separation within the secondary channel on the global flow within the primary duct and on flow split between primary and secondary channels are assessed, and it is demonstrated that actuation can effect significant changes in the flow fractions between the channels. Copyright 2015 Boeing. All rights reserved.

  15. Characterization of fish gelatin-gum arabic complex coacervates as influenced by phase separation temperature.

    PubMed

    Anvari, Mohammad; Pan, Cheol-Ho; Yoon, Won-Byong; Chung, Donghwa

    2015-08-01

    The rheological and structural characteristics of fish gelatin (FG)-gum arabic (GA) complex coacervate phase, separated from an aqueous mixture of 1% FG and 1% GA at pH 3.5, were investigated as influenced by phase separation temperature. Decreasing the phase separation temperature from 40 to 10 °C lead to: (1) the formation of a coacervate phase with a larger volume fraction and higher biopolymer concentrations, which is more viscous, more structural resistant at low shear rates, more shear-thinning at high shear rates, and more condensed in microstructure, (2) a solid-like elastic behavior of the phase separated at 10 °C at a high oscillatory frequency, (3) the increase in gelling and melting temperatures of the coacervate phase (3.7-3.9 °C and 6.2-6.9 °C, respectively), (4) the formation of a more rigid and thermo-stable coacervate gel. The coacervate phase is regarded as a homogeneously networked biopolymer matrix dispersed with water vacuoles and its gel as a weak physical gel reinforced by FG-GA attractive electrostatic interactions.

  16. Preparation and characterization of monoliths covalently bonded chelating groups for capillary electrochromatographic separation of metal ions.

    PubMed

    Wang, Guan-Ren; Huang, Kuan-Pin; Huang, Bao-Yu; Liu, Chuen-Ying

    2009-08-21

    In this work, a novel polymer-based monolithic column was prepared using an o-phthalaldehyde-l-phenylalanine Schiff base complex as the reactive center and a mixture of methanol and n-propanol as the porogen. The monolithic column was employed for the separation of a metal ion mixture including Pb(II), Mn(II), Cu(II), Ni(II), Cr(III), Fe(III) and Cr(VI). Tetrabutylammonium bromide (TBAB) was used as a mobile phase additive to enhance the separation efficiency of metal ions by EDTA precomplexation. Using a phosphate buffer (20 mM, pH 3.0), TBAB (10 mM), MeOH (15%, v/v), an applied voltage of -15 kV, and detection at 220 nm, the metal ion mixture was satisfactorily resolved. The average theoretical plate number was 17,900 plates/m. The separation was also carried out in the absence of TBAB, leading to dissimilar elution order and shorter retention time. The separation behavior of the monolithic column was also compared with that of the blank polymer. The unique properties of the monolithic column might be mediated by a combination of electrophoretic behavior and chromatographic retention involving hydrophobic and hydrophilic interactions, as well as ligand exchange.

  17. Characterization and reduction of flow separation in jet pumps for laminar oscillatory flows.

    PubMed

    Timmer, Michael A G; Oosterhuis, Joris P; Bühler, Simon; Wilcox, Douglas; van der Meer, Theo H

    2016-01-01

    A computational fluid dynamics model is used to predict the oscillatory flow through tapered cylindrical tube sections (jet pumps). The asymmetric shape of jet pumps results in a time-averaged pressure drop that can be used to suppress Gedeon streaming in closed-loop thermoacoustic devices. However, previous work has shown that flow separation in the diverging flow direction counteracts the time-averaged pressure drop. In this work, the characteristics of flow separation in jet pumps are identified and coupled with the observed jet pump performance. Furthermore, it is shown that the onset of flow separation can be shifted to larger displacement amplitudes by designs that have a smoother transition between the small opening and the tapered surface of the jet pump. These design alterations also reduce the duration of separated flow, resulting in more effective and robust jet pumps. To make the proposed jet pump designs more compact without reducing their performance, the minimum big opening radius that can be implemented before the local minor losses have an influence on the jet pump performance is investigated. To validate the numerical results, they are compared with experimental results for one of the proposed jet pump designs.

  18. Separation and characterization of the immunostimulatory components in unpolished rice black vinegar (kurozu).

    PubMed

    Hashimoto, Masahito; Obara, Kyoko; Ozono, Mami; Furuyashiki, Maiko; Ikeda, Tsuyoshi; Suda, Yasuo; Fukase, Koichi; Fujimoto, Yukari; Shigehisa, Hiroshi

    2013-12-01

    Unpolished rice black vinegar (kurozu), a traditional Japanese vinegar, is considered to have beneficial health effects. Kurozu is produced via a static fermentation process involving the saccharification of rice by Aspergillus oryzae, alcohol fermentation by Saccharomyces cerevisiae, and the oxidation of ethanol to acetic acid by acetic acid bacteria such as Acetobacter pasteurianus. Since this process requires about 6 months' fermentation and then over a year of aging, most of these organisms die during the production process and so microbial components, which might stimulate the innate immune system, are expected to be present in the vinegar. In this study, we investigated whether microbial components are present in kurozu, and after confirming this we characterized their immunostimulatory activities. Lyophilized kurozu stimulated murine spleen cells to produce tumor necrosis factor (TNF)-α, at least in part, via Toll-like receptor (TLR) 2 and the Nod-like receptors NOD1 and 2. The active components associated with TLR2 activation were concentrated by Triton X-114-water phase partitioning and hydrophobic interaction chromatography on Octyl Sepharose. TLR4-activating components were also enriched by these methods. The concentrated preparation stimulated murine spleen cells to produce TNF-α and interferon (IFN)-γ. These results indicate that long-term fermented kurozu contains immunostimulatory components and that the TLR2 and TLR4-activating immunostimulatory components of kurozu are hydrophobic. These components might be responsible for the beneficial health effects of kurozu.

  19. CO2 Capture and Separations Using MOFs: Computational and Experimental Studies.

    PubMed

    Yu, Jiamei; Xie, Lin-Hua; Li, Jian-Rong; Ma, Yuguang; Seminario, Jorge M; Balbuena, Perla B

    2017-04-10

    This Review focuses on research oriented toward elucidation of the various aspects that determine adsorption of CO2 in metal-organic frameworks and its separation from gas mixtures found in industrial processes. It includes theoretical, experimental, and combined approaches able to characterize the materials, investigate the adsorption/desorption/reaction properties of the adsorbates inside such environments, screen and design new materials, and analyze additional factors such as material regenerability, stability, effects of impurities, and cost among several factors that influence the effectiveness of the separations. CO2 adsorption, separations, and membranes are reviewed followed by an analysis of the effects of stability, impurities, and process operation conditions on practical applications.

  20. The mandibular condylar growth center: separation and characterization of the cellular elements.

    PubMed

    Landesberg, R; Proctor, R L; Rosier, R N; Puzas, J E

    1995-01-01

    The developing mandibular condylar growth center consists of a number of histologically distinct cell types. There is an increase in cell volume that takes place from the condylar surface layer through the center of ossification, resulting in a disorganized, irregular cellular pattern. Consequently, the isolation and separation of the different cells from this tissue is difficult using standard methodologies. Countercurrent centrifugal elutriation, whereby cells are separated on the basis of size, was applied to bovine mandibular condylar growth center cells. The cell volume, alkaline phosphatase content, proteoglycan synthesis, and type X collagen synthesis all showed a positive correlation with increasing cell size. The largest cells had characteristics that are consistent with hypertrophic chondrocytes; the smallest cells, on the other hand, had many fibroblastic characteristics.

  1. Characterization of magnetic ion-exchange composites for protein separation from biosuspensions.

    PubMed

    Käppler, Tobias E; Hickstein, Birgit; Peuker, Urs A; Posten, Clemens

    2008-06-01

    Downstream processing is a major issue in biotechnological production. A multitude of unit operations with nonsatisfying yield are often used to reach the desired product purity. Direct recovery technologies such as high-gradient magnetic fishing (HGMF) are advantageous because of their ability to separate the desired product in early stages from crude cultivation broths. However, the use of magnetic particles to capture valuable biotechnological products is often linked to the drawback that support particles are expensive and not available in greater quantities. This current work presents new composite magnetic particles that can be used in biotechnology. They are manufactured by a spray drying process. During this process, the nanosized magnetite particles as well as functional ion-exchange nanoparticles are integrated into one particle in which they are linked by a matrix polymer. The production procedure is flexible, scalable, and therefore economical. These particles have good adsorption capacities of up to 85 mg/g adsorbed protein and good binding kinetics. They are resistant to harsh conditions such as short ultrasonic treatment or extreme pHs. In order to test their usefulness in biosuspensions, model proteins were separated using these particles. The anion and cation exchanger particles separated lysozyme (LZ) or BSA from cultivation suspensions. The selectivity of recovery was dependent on other proteins present as is usual for ion-exchange binding mechanisms.

  2. Separation and characterization of lignin from bio-ethanol production residue.

    PubMed

    Guo, Guowan; Li, Shujun; Wang, Lu; Ren, Shixue; Fang, Guizhen

    2013-05-01

    In order to develop an adequate method to separate lignin from bio-ethanol production residue, solvent extraction was conducted by using benzyl alcohol, dioxane and ethanol. Compared to the conventional alkali-solution and acid-isolation method, benzyl alcohol and dioxane extraction could reach higher lignin yield of 71.55% and 74.14% respectively. FTIR and XRD analysis results indicate that sodium hydroxide solution dissolved most of the lignin in the raw material. However, the low lignin yield by this method may be attributed to the products loss during the complex separation process. GPC and (1)H NMR results revealed that the dioxane-lignin had closer molecular weight with alkali-lignin, lower S/G ratio (0.22) and higher OHPh/OHAl ratio (0.45) with respect to benzyl alcohol-lignin. The results divulge that the lignin products separated from bio-ethanol production residue by dioxane extraction had fairly potential application with better chemical activity.

  3. Parametric study on phase separation of binary mixtures in a lid driven cavity: A DPD study

    NASA Astrophysics Data System (ADS)

    Gidituri, Harinadha; Anand, Vijay; Panchagnula, Mahesh; Vedantam, Srikanth

    2016-11-01

    We investigate the phase separation behavior of binary mixtures in two dimensional periodic and lid driven cavity domains using dissipative particle dynamics (DPD). The effect of DPD parameters like repulsion coefficient, dissipative coefficient, cut-off radius, and weight function exponent on domain size growth has been studied. The phase separation is delayed for low values of repulsion coefficient. Under these conditions, a few clusters of the dispersed phase are distributed in a continuous phase. This is because of weak inter-particle repulsion. As we increase the repulsion coefficient value, this behavior disappears. The domain growth rate is also observed to increase with an increase in the value of the dissipation coefficient as well as cut-off radius. Finally, the dynamics of phase separation in the lid driven cavity problem are significantly different when compared to that in the periodic domain, due to the formation of a stable vortex in the cavity. The vortex results in a dynamic equilibrium between clustering and separation. The distribution of cluster sizes is studied as a function of the driven cavity parameters.

  4. Characterization of the Axial Jet Separator with a CO2/Helium Mixture: Toward GC-AMS Hyphenation.

    PubMed

    Salazar, G; Agrios, K; Eichler, R; Szidat, S

    2016-02-02

    Development of interfaces for sample introduction from high pressures is important for real-time online hyphenation of chromatographic and other separation devices with mass spectrometry (MS) or accelerator mass spectrometry (AMS). Momentum separators can reduce unwanted low-density gases and introduce the analyte into the vacuum. In this work, the axial jet separator, a new momentum interface, is characterized by theory and empirical optimization. The mathematical model describes the different axial penetration of the components of a jet-gas mixture and explains the empirical results for injections of CO2 in helium into MS and AMS instruments. We show that the performance of the new interface is sensitive to the nozzle size, showing good qualitative agreement with the mathematical model. Smaller nozzle sizes are more preferable due to their higher inflow capacity. The CO2 transmission efficiency of the interface into a MS instrument is ∼ 14% (CO2/helium separation factor of 2.7). The interface receives and delivers flows of ∼ 17.5 mL/min and ∼ 0.9 mL/min, respectively. For the interfaced AMS instrument, the ionization and overall efficiencies are 0.7-3% and 0.1-0.4%, respectively, for CO2 amounts of 4-0.6 μg C, which is only slightly lower compared to conventional systems using intermediate trapping. The ionization efficiency depends on to the carbon mass flow in the injected pulse and is suppressed at high CO2 flows. Relative to a conventional jet separator, the transmission efficiency of the axial jet separator is lower, but its performance is less sensitive to misalignments.

  5. Oxidation, characterization, and separation of non-pertechnetate species in Hanford wastes

    SciTech Connect

    Schroeder, N.C.

    1997-10-01

    Under DOE`s privatization initiative, Lockheed Martin and British Nuclear Fuels Limited are preparing to stabilize the caustic tank waste generated from plutonium production at the Hanford Site. Pretreatment of Hanford tank waste will separate it into low-level waste (LLW) and high-level waste (HLW) fractions. The scope of the technetium problem is indicated by its inventory in the waste: {approximately}2000 kg. Technetium would normally exist as the pertechnetate anion, TcO{sub 4}{sup {minus}}, in aqueous solution. However, evidence obtained at Los Alamos National Laboratory (LANL) indicates that the combination of radiolysis, heat, organic complexants, and time may have reduced and complexed a significant fraction of the technetium in the tank waste. These species are in a form that is not amenable to current separation techniques based on pertechnetate removal. Thus, it is crucial that methods be developed to set technetium to pertechnetate so these technologies can meet the required technetium decontamination factor. If this is not possible, then alternative separation processes will need to be developed to remove these non-pertechnetate species from the waste. The simplest, most cost-effective approach to this problem is to convert the non-pertechnetate species to pertechnetate. Chemical, electrochemical, and photochemical oxidation methods, as well as hydrothermal treatment, are being applied to Hanford waste samples to ensure that the method works on the unknown technetium species in the waste. The degree of oxidation will be measured by determining the technetium distribution coefficient, {sup Tc}K{sub d}, between the waste and Reillex{trademark}-HPQ resin, and comparing it to the true pertechnetate K{sub d} value for the waste matrix. Other species in the waste, including all the organic material, could be oxidized by these methods, thus selective oxidation is desirable to minimize the cost, time, and secondary waste generation.

  6. Characterization of a Reversible Thermoresponsive Gel and Its Application to Oligonucleotide Separation

    SciTech Connect

    Zhang,J.; Gassman, M.; Chen, X.; Burger, C.; Rong, L.; Ying, Q.; Chu, B.

    2007-01-01

    Pluronic mixtures of F87 (E{sub 61}P{sub 40}E{sub 61}) and F127 (E{sub 99}P{sub 69}E{sub 99}), with E and P being poly(ethylene oxide) and poly(propylene oxide), respectively, have been used as effective separation media for the separation of small charged biomacromolecules, such as oligonulceotide fragments, by microchip electrophoresis. The temperature-dependent solubility of the middle block (P{sub 40} or P{sub 69}) enables a convenient micelle formation of the triblock copolymer by self-assembly, forming ordered gel-like macrolattice structures at high polymer concentrations or high temperatures. Laser light scattering (LLS) and small-angle X-ray scattering (SAXS) were used to investigate the solution behavior, including the gel structure. Micelles of the F87/F127 mixture solution at different weight ratios almost had a constant hydrodynamic radius of about 10.6 nm, except for the pure F87 solution with a hydrodynamic radius size of about 6.3 nm. The aggregation number of the micelle increased from {approx}5 to {approx}17 with an increase in the F127 content in the solution. On the basis of the SAXS results, the macrolattice symmetry of the gel-like structure could be determined. Two kinds of ordered gel structures were observed: body-centered cubic (bcc, F87-rich region) and face-centered cubic (fcc, F127-rich region). There was a transition region between them whose structure had not yet been resolved. The cubic lattice constant decreased with increasing F87 content in the mixture. Under optimized conditions, oligonucleotide sizing markers ranging from 10 to 32 bases could be separated within 40 s with one-base resolution by microchip electrophoresis.

  7. Corrosion study in the chemical air separation (MOLTOX trademark ) process

    SciTech Connect

    Kang, Doohee; Wong, Kai P.; Archer, R.A.; Cassano, A.A.

    1988-12-01

    This report presents the results of studies aimed at solving the corrosion problems encountered during operation of the MOLTOX{trademark} pilot plant. These studies concentrated on the screening of commercial and developmental alloys under conditions simulating operation conditions in this high temperature molten salt process. Process economic studies were preformed in parallel with the laboratory testing to ensure that an economically feasible solution would be achieved. In addition to the above DOE co-funded studies, Air Products and Chemicals pursued proprietary studies aimed at developing a less corrosive salt mixture which would potentially allow the use of chemurgically available alloys such as stainless steels throughout the system. These studies will not be reported here; however, the results of corrosion tests in the new less corrosive salt mixtures are reported. Because our own studies on salt chemistry impacts heavily on the overall process and thereby has an influence on the experimental work conducted under this contract, some of the studies discussed here were impacted by our own proprietary data. Therefore, the reasons behind some of the experiments presented herein will not be explained because that information is proprietary to Air Products. 14 refs., 42 figs., 21 tabs.

  8. Multidimensional Mass Spectrometry Coupled with Separation by Polarity or Shape for the Characterization of Sugar-Based Nonionic Surfactants.

    PubMed

    Katzenmeyer, Bryan C; Hague, Shayna F; Wesdemiotis, Chrys

    2016-01-05

    Mass spectrometry (MS) and tandem mass spectrometry (MS/MS) were interfaced with ultra-performance liquid chromatography (UPLC) and ion mobility (IM) separation to characterize a complex nonionic surfactant, consisting of a methylated glucose core (glucam) conjugated with poly(ethylene oxide) (PEO(n)) branches that were partially esterified with stearic acid to form ethoxylated glucam (PEO(n)-glucam) stearates. Reverse-phase LC-MS afforded fast separation according to polarity into five major fractions. Accurate mass measurements of the ions in the mass spectra extracted from these fractions enabled conclusive identification of six components in the surfactant, including PEO(n)-glucam mono-, di-, and tristearates as well as free and esterified PEO(n) as byproducts. MS/MS experiments provided corroborating evidence for the fatty acid content in each fraction based on the number of stearic acid losses observed. With IM-MS, the total surfactant ions were separated according to charge and shape into four distinct bands. Extracted mass spectra confirmed the presence of two disaccharide stearates in the surfactant, which were undetectable by LC-MS. PEO(n)-glucam tristearates were, however, not observed upon IM-MS. Hence, LC-MS and IM-MS unveiled complementary compositional insight. With each method, certain components were particularly well separated from other ingredients (by either polarity or shape), to be detected with confidence. Consequently, combined LC-MS and IM-MS offer a superior approach for the characterization of surfactants and other amphiphilic polymers and for the differentiation of similarly composed amphiphilic blends. It is finally noteworthy that NH4(+) charges minimized chemical noise in MS mode and Li(+) charges maximized the fragmentation efficiency in MS/MS mode.

  9. Source separation of municipal solid waste: The effects of different separation methods and citizens' inclination-case study of Changsha, China.

    PubMed

    Chen, Haibin; Yang, Yan; Jiang, Wei; Song, Mengjie; Wang, Ying; Xiang, Tiantian

    2017-02-01

    A case study on the source separation of municipal solid waste (MSW) was performed in Changsha, the capital city of Hunan Province, China. The objective of this study is to analyze the effects of different separation methods and compare their effects with citizens' attitudes and inclination. An effect evaluation method based on accuracy rate and miscellany rate was proposed to study the performance of different separation methods. A large-scale questionnaire survey was conducted to determine citizens' attitudes and inclination toward source separation. Survey result shows that the vast majority of respondents hold consciously positive attitudes toward participation in source separation. Moreover, the respondents ignore the operability of separation methods and would rather choose the complex separation method involving four or more subclassed categories. For the effects of separation methods, the site experiment result demonstrates that the relatively simple separation method involving two categories (food waste and other waste) achieves the best effect with the highest accuracy rate (83.1%) and the lowest miscellany rate (16.9%) among the proposed experimental alternatives. The outcome reflects the inconsistency between people's environmental awareness and behavior. Such inconsistency and conflict may be attributed to the lack of environmental knowledge. Environmental education is assumed to be a fundamental solution to improve the effect of source separation of MSW in Changsha. Important management tips on source separation, including the reformation of the current pay-as-you-throw (PAYT) system, are presented in this work.

  10. Separation and characterization of alpha-chain subunits from tilapia (Tilapia zillii) skin gelatin using ultrafiltration.

    PubMed

    Chen, Shulin; Tang, Lanlan; Su, Wenjin; Weng, Wuyin; Osako, Kazufumi; Tanaka, Munehiko

    2015-12-01

    Alpha-chain subunits were separated from tilapia skin gelatin using ultrafiltration, and the physicochemical properties of obtained subunits were investigated. As a result, α1-subunit and α2-subunit could be successfully separated by 100 kDa MWCO regenerated cellulose membranes and 150 kDa MWCO polyethersulfone membranes, respectively. Glycine was the most dominant amino acid in both α1-subunit and α2-subunit. However, the tyrosine content was higher in α2-subunit than in α1-subunit, resulting in strong absorption near 280 nm observed in the UV absorption spectrum. Based on the DSC analysis, it was found that the glass transition temperatures of gelatin, α1-subunit and α2-subunit were 136.48 °C, 126.77 °C and 119.43 °C, respectively. Moreover, the reduced viscosity and denaturation temperature of α1-subunit were higher than those of α2-subunit, and the reduced viscosity reached the highest when α-subunits were mixed with α1/α2 ratio of approximately 2, suggesting that α1-subunit plays a more important role in the thermostability of gelatin than α2-subunit.

  11. Factors Moderating Children's Adjustment to Parental Separation: Findings from a Community Study in England

    ERIC Educational Resources Information Center

    Cheng, Helen; Dunn, Judy; O'Connor, Thomas G.; Golding, Jean

    2006-01-01

    Research findings show that there is marked variability in children's response to parental separation, but few studies identify the sources of this variation. This prospective longitudinal study examines the factors modifying children's adjustment to parental separation in a community sample of 5,635 families in England. Children's…

  12. A lipoprotein characterizing obstructive jaundice. I. Method for quantitative separation and identification of lipoproteins in jaundiced subjects

    PubMed Central

    Seidel, D.; Alaupovic, P.; Furman, R. H.

    1969-01-01

    Three immunochemically and electrophoretically distinct lipoproteins, LP-A, LP-B, and LP-X,1 were isolated from the low density lipoprotein fraction (1.006-1.063 g/ml) in plasma from patients with biliary obstruction by a separation procedure which combines ultracentrifugation, heparin precipitation, and ethanol fractionation. This method, here described, permits the quantitative determination of individual plasma lipoprotein families on the basis of their protein moieties, rather than on the basis of their lipid moieties or density. The chemical composition of the unique lipoprotein, LP-X, was similar to that of an abnormal lipoprotein, OLP, isolated by Russ et al. (29) and by Switzer (30). In obstructive jaundice plasma, the combined LP-X and LP-B accounted for 98% and the LP-A for only 2% of the total protein content of the LDL fraction. This study indicates that the plasma lipoprotein pattern in obstructive jaundice is characterized by (a) a decreased concentration of HDL, (b) an increased concentration of LDL, and (c) the presence in the LDL fraction of varying amounts of a specific lipoprotein, LP-X, immunochemically and chemically distinct from LP-A and LP-B. LP-X, with its characteristically high content of unesterified cholesterol and phospholipids, is primarily responsible for the unusual protein and lipid content of the LDL fraction. Screening tests in 61 patients with various forms of jaundice indicated that a characteristic immunoelectrophoretic precipitin are between plasma samples and purified antibodies to LP-X was observed only in patients with obstructive jaundice. This simple immunochemical test may represent a valuable new tool in the differential diagnosis of obstructive and nonobstructive jaundice. Images PMID:4978447

  13. SANS study of phase separation in solid {sup 3}He-{sup 4}He

    SciTech Connect

    Koster, J.P.; Nagler, S.E.; Adams, E.D.; Wignall, G.D.

    1994-12-31

    Small angle neutron scattering has been used to study phase separation in a quantum alloy, solid {sup 3}He{sub x}-{sup 4}He{sub 1{minus}x}. The onset of phase separation is marked by a dramatic increase in the measured scattering. A simple interpretation of the results suggests that the late-stage phase separation kinetics are dominated by an increase in the concentration of {sup 3}He atoms in preexisting precipitate regions.

  14. Structural characterization of synthetic polymers and copolymers using multidimensional mass spectrometry interfaced with thermal degradation, liquid chromatography and/or ion mobility separation

    NASA Astrophysics Data System (ADS)

    Alawani, Nadrah

    This dissertation focuses on coupling mass spectrometry (MS) and tandem mass spectrometry (MS/MS) to thermal degradation, liquid chromatography (LC) and/or ion mobility (IM) spectrometry for the characterization of complex mixtures. In chapter II, an introduction of the history and the principles of MS and LC are discussed. Chapter III illustrates the materials and instrumentation used to complete this dissertation. Polyethers have been characterized utilizing MS/MS, as presented in Chapter IV and Chapter VI. Diblock copolymers of polyethylene oxide and polycaprolactone, PEO-b-PCL, have been characterized by matrix-assisted laser desorption/ionization quadrupole/time-of-flight mass spectrometry (MALDI-Q/ToF) and LC-MS/MS (Chapter V). Thermoplastic elastomers have been characterized by thermal degradation using an atmospheric solids analysis probe (ASAP) and ion mobility mass spectrometry (IM-MS), as discussed in Chapter VII. Interfacing separation techniques with mass spectrometry permitted the detection of species present with low concentration in complex materials and improved the sensitivity of MS. In chapter IV, the fragmentation mechanisms in MS/MS experiments of cyclic and linear poly(ethylene oxide) macroinitiators are discussed. This study aimed at determining the influence of end groups on the fragmentation pathways. In the study reported in Chapter V, ultra high performance liquid chromatography (UHPLC) was interfaced with MS and MS/MS to achieve the separation and in-depth characterization and separation of amphiphilic diblock copolymers (PEO- b-PCL) in which the architecture of the PEO block is linear or cyclic. Applying UPLC-MS and UPLC-MS/MS provides fast accurate information about the number and type of the blocks in the copolymers. Chapter VI reports MS/MS and IM-MS analyses which were performed to elucidate the influence of molecular size and collision energy on the fragmentation pathways of polyethers subjected to collisionally activated

  15. Formation and characterization of asymmetric polyimide hollow fiber membranes for gas separations

    NASA Astrophysics Data System (ADS)

    Clausi, Dominic Thomas

    Ultra-thin and virtually defect-free polyimide hollow fiber membranes were formed using a "dry/wet" type spinning solution. Fibers were spun from the commercially available polyimide, Matrimidsp{°ler}, using a dry-jet, wet quench spinning apparatus. Spin dopes were comprised of volatile and non-volatile solvents, polymer, and non-solvent. The influence of dope composition, spinning parameters, and dehydration procedures on the membrane morphology and performance was investigated. Without post-treatment, the fibers exhibited skin thicknesses less than 1000 A and Osb2/Nsb2 selectivities within 90% of those determined for dense, solution-cast films. The 250 mum O.D./125 mum I.D. fibers were spun at take-up rates comparable to those used in commercial processes and had macrovoid-free morphologies. A new characterization technique has also been developed where a permeating gas is held at constant transmembrane pressure while the average pressure in the porous support of an asymmetric membrane is varied. This alters the mean free path of gas molecules permeating through the substructure while maintaining a constant driving force for permeation. This technique characterizes the magnitude of the substructure resistance and its pressure dependence, thereby providing a means to compare the morphologies of different membrane samples. Well defined composite-laminate membranes were constructed to validate this technique, which was subsequently used to characterize the substructures of the hollow fiber membranes formed in this work. Two additional rapid characterization techniques have been developed for use before fiber dehydration (i.e., wet fibers). These techniques probe the membrane skin layer with aqueous solutions of disperse dyes and poly(ethylene glycol), respectively. Fiber skin integrity can be characterized using these techniques prior to lengthy downstream processing (i.e., solvent exchange, drying, and post-treatment), providing quick elucidation of membrane skin

  16. Location and characterization of two widely separated glucocorticoid response elements in the phosphoenolpyruvate carboxykinase gene

    SciTech Connect

    Petersen, D.D.; Magnuson, M.A.; Granner, D.K.

    1988-01-01

    Chimeric genes were constructed by fusion of various regions of the 5'-flanking sequence from the phosphoenolpyruvate carboxykinase (GTP) (PEPCK) gene to the chloramphenicol acetyltransferase-coding sequence and to simian virus 40 splice and polyadenylation sequences. These were used to demonstrate that two glucocorticoid regulatory elements (GREs) combine to confer glucocorticoid responsiveness upon the PEPCK gene in H4IIE hepatoma cells. Both elements, distal one whose 5' boundary is located between -1264 and -1111 base pairs and a proximal one located between -468 and -420 base pairs relative to the transcription initiation site, act independently, in various positions and orientations, and upon the heterologous thymidine kinase promoter. Each element accounts for half of the maximal response of the chimeric genes. Therefore, two widely separated enhancerlike elements contribute equally to the response of the PEPCK gene to glucocorticoid hormones. Neither of the PEPCK GREs contains the TGTTCT consensus sequence associated with most other GREs.

  17. Location and characterization of two widely separated glucocorticoid response elements in the phosphoenolpyruvate carboxykinase gene.

    PubMed Central

    Petersen, D D; Magnuson, M A; Granner, D K

    1988-01-01

    Chimeric genes were constructed by fusion of various regions of the 5'-flanking sequence from the phosphoenolpyruvate carboxykinase (GTP) (PEPCK) gene to the chloramphenicol acetyltransferase-coding sequence and to simian virus 40 splice and polyadenylation sequences. These were used to demonstrate that two glucocorticoid regulatory elements (GREs) combine to confer glucocorticoid responsiveness upon the PEPCK gene in H4IIE hepatoma cells. Both elements, a distal one whose 5' boundary is located between -1264 and -1111 base pairs and a proximal one located between -468 and -420 base pairs relative to the transcription initiation site, act independently, in various positions and orientations, and upon the heterologous thymidine kinase promoter. Each element accounts for half of the maximal response of the chimeric genes. Therefore, two widely separated enhancerlike elements contribute equally to the response of the PEPCK gene to glucocorticoid hormones. Neither of the PEPCK GREs contains the TGTTCT consensus sequence associated with most other GREs. Images PMID:3422101

  18. A feasibility study of magnetic separation of magnetic nanoparticle for forward osmosis.

    PubMed

    Kim, Y C; Han, S; Hong, S

    2011-01-01

    It was recently reported that a UK company has developed a naturally non-toxic magnetoferritin to act as a draw solute for drawing water in forward osmosis process. The gist of this technology is the utilization of the magnetic nanoparticle and high-gradient magnetic separation for draw solute separation and reuse. However, any demonstration on this technology has not been reported yet. In this study, a feasibility test of magnetic separation using magnetic nanoparticle was therefore performed to investigate the possibility of magnetic separation in water treatment such as desalination. Basically, a magnetic separation system consisted of a column packed with a bed of magnetically susceptible wools placed between the poles of electromagnet and Fe3O4 magnetic nanoparticle was used as a model nanoparticle. The effect of nanoparticle size to applied magnetic field in separation column was experimentally investigated and the magnetic field distribution in a magnet gap and the magnetic field gradient around stainless steel wool wire were analyzed through numerical simulation. The amount of magnetic nanoparticle captured in the separator column increased as the magnetic field strength and particle size increased. As a result, if magnetic separation is intended to be used for draw solute separation and reuse, both novel nanoparticle and large-scale high performance magnetic separator must be developed.

  19. Capillary electrophoretic separation of humic substances using hydroxyethyl cellulose as a buffer additive and its application to characterization of humic substances in a river water sample.

    PubMed

    Takahashi, Toru; Kawana, Jun; Hoshino, Hitoshi

    2009-01-01

    We have developed a concise tool for the investigation of the transition of humic substances in environmental water. The separation of water-soluble humic substances was achieved rapidly and effectively by capillary electrophoresis using a polyacrylamide-coated capillary and a phosphate electrophoretic buffer solution (pH 7.0) containing hydroxyethyl cellulose. The separation mechanism was assessed using the ultrafiltration technique. The effect of the complexation of humic substances with metal ions was studied by using the proposed method. When Fe(III) ions or EDTA was added to the sample solution of fulvic acid, a distinct change in the electropherogram pattern based on the conformational change of fulvic acid was observed. The successful application of the proposed method to the characterization of humic substances in a river water sample was also demonstrated.

  20. Isolation of murine postnatal brain microglia for phenotypic characterization using magnetic cell separation technology.

    PubMed

    Harms, Ashley S; Tansey, Malú G

    2013-01-01

    To shorten the time between brain harvesting and microglia isolation, and characterization, we utilized the MACS(®) neural dissociation kit followed by OctoMACS(®) CD11b magnetic bead isolation technique to positively select for brain microglia expressing the pan-microglial marker CD11b, a key subunit of the membrane attack complex (MAC). This protocol yields a viable and highly pure (>95%) microglial population of approximately 500,000 cells per pup that is amenable for in vitro characterization within hours or days after being harvested from brain tissue. Primary microglia from C57Bl/6 mice were plated for next-day analyses of morphology and cellular markers by immunocytochemistry or for analysis of gene expression under resting or LPS-stimulated conditions. The ease of isolation enables investigators to perform molecular and cellular analyses without having to wait 1-2 weeks to isolate microglia by conventional methods involving mechanical agitation to dislodge these from astrocyte beds.

  1. Separation and characterization of phenolic compounds from U.S. pecans by liquid chromatography-tandem mass spectrometry.

    PubMed

    Robbins, Katherine S; Ma, Yuanyuan; Wells, M Lenny; Greenspan, Phillip; Pegg, Ronald B

    2014-05-14

    The phenolic acids and proanthocyanidins (PACs) of pecans possess bioactive properties, which might be useful in retarding the onset of and ameliorating the status of certain chronic disease states. There is a general lack of information in the literature regarding such compounds, especially the PACs. Crude phenolic extracts pooled from eight commercially significant cultivars were selected based on their relatively high antioxidant capacities. The pooled extracts were separated via Sephadex LH-20 column chromatography into five ethanolic low-molecular-weight (LMW) fractions and one acetonic high-molecular-weight (HMW) fraction. The preparations were then characterized using RP-HPLC-ESI-MS/MS and diol-phase HPLC-ESI-MS/MS in order to determine the key constituents present in the LMW and HMW fractions, respectively. As previously observed in pecan nutmeat, ellagic acid and (+)-catechin were found to be the major phenolics in the LMW fractions. The last eluting LMW fraction did not contain phenolic acids; rather it possessed PAC monomers and dimers. The HMW fraction comprised a majority of its PACs as dimers; yet, monomers, trimers, tetramers, pentamers, and hexamers were also separated and characterized.

  2. Synthesis and Characterization of PLGA Shell Microcapsules Containing Aqueous Cores Prepared by Internal Phase Separation.

    PubMed

    Abulateefeh, Samer R; Alkilany, Alaaldin M

    2016-08-01

    The preparation of microcapsules consisting of poly(D,L-lactide-co-glycolide) (PLGA) polymer shell and aqueous core is a clear challenge and hence has been rarely addressed in literature. Herein, aqueous core-PLGA shell microcapsules have been prepared by internal phase separation from acetone-water in oil emulsion. The resulting microcapsules exhibited mean particle size of 1.1 ± 0.39 μm (PDI = 0.35) with spherical surface morphology and internal poly-nuclear core morphology as indicated by scanning electron microscopy (SEM). The incorporation of water molecules into PLGA microcapsules was confirmed by differential scanning calorimetry (DSC). Aqueous core-PLGA shell microcapsules and the corresponding conventional PLGA microspheres were prepared and loaded with risedronate sodium as a model drug. Interestingly, aqueous core-PLGA shell microcapsules illustrated 2.5-fold increase in drug encapsulation in comparison to the classical PLGA microspheres (i.e., 31.6 vs. 12.7%), while exhibiting sustained release behavior following diffusion-controlled Higuchi model. The reported method could be extrapolated to encapsulate other water soluble drugs and hydrophilic macromolecules into PLGA microcapsules, which should overcome various drawbacks correlated with conventional PLGA microspheres in terms of drug loading and release.

  3. Characterization of the PVC phenomena in the exhaust of a cyclone dust separator

    NASA Astrophysics Data System (ADS)

    Yazdabadi, P. A.; Griffiths, A. J.; Syred, N.

    1994-06-01

    A laboratory scale cyclone dust separator with swirl numbers varying from 3.043 to 1.790 was used to examine the effects of different downstream pipework configurations, flowrates and swirl numbers upon the size, shape, and position of the precessing vortex core. Also examined was the effect the precessing vortex core had on the reverse flow zone, and the relationship between the two. It was concluded that the reverse flow zone displaced the central vortex core to create the precessing vortex core. The reverse flow zone would then provide feedback for the precessing vortex core, and precess around the central axis about 30 degrees behind the precessing vortex core (P.V.C). The size and position of the P.V.C was effected by changes in Reynolds number, and any additions of downstream systems to the cyclone would also affect the strength of the P.V.C. The P.V.C would squeeze and accelerate the flow through a constriction set up between the outer limits of the core and of the exit diameter wall. Spiral engulfment vortices were produced on the outside of the flow and served as the initial entrainment mechanism for external flow.

  4. Ordered macroporous quercetin molecularly imprinted polymers: Preparation, characterization, and separation performance.

    PubMed

    Feng, Yonggang; Liu, Qin; Ye, Lifang; Wu, Quanzhou; He, Jianfeng

    2017-02-01

    Ordered macroporous molecularly imprinted polymers were prepared by a combination of the colloidal crystal templating method and the molecular imprinting technique by using SiO2 colloidal crystal as the macroporogen, quercetin as the imprinting template, acrylamide as the functional monomer, ethylene glycol dimethacrylate as the cross-linker and tetrahydrofuran as the solvent. Scanning electron microscopy and Brunauer-Emmett-Teller measurements show that the ordered macroporous molecularly imprinted polymers have a more regular macroporous structure, a narrower pore distribution and a greater porosity compared with the traditional bulk molecularly imprinted polymers. The kinetic and isothermal adsorption behaviors of the polymers were investigated. The results indicate that the ordered macroporous molecularly imprinted polymers have a faster intraparticle mass transfer process and a higher adsorption capacity than the traditional bulk molecularly imprinted polymers. The ordered macroporous molecularly imprinted polymers were further employed as a sorbent for a solid-phase extraction. The results show that the ordered macroporous molecularly imprinted polymers can effectively separate quercetin from the Gingko hydrolysate.

  5. Density Functional Reactivity Theory Characterizes Charge Separation Propensity in Proton-Coupled Electron Transfer Reactions

    SciTech Connect

    Liu, Shubin; Ess, Daniel H.; Schauer, Cynthia

    2011-04-20

    Proton-coupled electron transfer (PCET) reactions occur in many biological and artificial solar energy conversion processes. In these reactions the electron is often transferred to a site distant to the proton acceptor site. In this work, we employ the dual descriptor and the electrophilic Fukui function from density functional reactivity theory (DFRT) to characterize the propensity for an electron to be transferred to a site other than the proton acceptor site. The electrophilic regions of hydrogen bond or van der Waal reactant complexes were examined using these DFRT descriptors to determine the region of space to which the electron is most likely to be transferred. This analysis shows that in PCET reactions the electrophilic region of the reactant complex does not include the proton acceptor site.

  6. Size separation method for absorption characterization in brown carbon: Application to an aged biomass burning sample

    NASA Astrophysics Data System (ADS)

    Di Lorenzo, Robert A.; Young, Cora J.

    2016-01-01

    The majority of brown carbon (BrC) in atmospheric aerosols is derived from biomass burning (BB) and is primarily composed of extremely low volatility organic carbons. We use two chromatographic methods to compare the contribution of large and small light-absorbing BrC components in aged BB aerosols with UV-vis absorbance detection: (1) size exclusion chromatography (SEC) and (2) reverse phase high-performance liquid chromatography. We observe no evidence of small molecule absorbers. Most BrC absorption arises from large molecular weight components (>1000 amu). This suggests that although small molecules may contribute to BrC absorption near the BB source, analyses of aerosol extracts should use methods selective to large molecular weight compounds because these species may be responsible for long-term BrC absorption. Further characterization with electrospray ionization mass spectrometry (MS) coupled to SEC demonstrates an underestimation of the molecular size determined through MS as compared to SEC.

  7. Hyperbranched polyglycerol-grafted titanium oxide nanoparticles: synthesis, derivatization, characterization, size separation, and toxicology

    NASA Astrophysics Data System (ADS)

    Qin, Hongmei; Maruyama, Kyouhei; Amano, Tsukuru; Murakami, Takashi; Komatsu, Naoki

    2016-10-01

    We have been developing surface functionalization of various nanoparticles including nanodiamond and iron oxide nanoparticles in view of biomedical applications. In this context, TiO2 nanoparticles (TiO2 NP) are functionalized with polyglycerol (PG) to provide water-dispersible TiO2-PG, which is further derivatized through multi-step organic transformations. The resulting TiO2-PG and its derivatives are fully characterized by various analyses including solution-phase 1H and 13C NMR. TiO2-PG was size-tuned with centrifugation by changing the acceleration and duration. At last, no cytotoxicity of TiO2 NP, TiO2-PG, and TiO2-PG functionalized with RGD peptide was observed under dark conditions.

  8. CHARACTERIZATION OF MODIFIED MONOSODIUM TITANATE - AN IMPROVED SORBENT FOR STRONTIUM AND ACTINIDE SEPARATIONS

    SciTech Connect

    Hobbs, D.; Taylor-Pashow, K.; Missimer, D.

    2010-12-21

    High-level nuclear waste produced from fuel reprocessing operations at the Savannah River Site (SRS) requires pretreatment to remove {sup 134,137}Cs, {sup 90}Sr, and alpha-emitting radionuclides (i.e., actinides) prior to disposal onsite as low level waste. An inorganic sorbent, monosodium titanate (MST), is currently used to remove {sup 90}Sr and alpha-emitting radionuclides, while a caustic-side solvent extraction process is used for removing {sup 134,137}Cs. A new peroxotitanate material, modified MST, or mMST, has recently been developed and has shown increased removal kinetics and capacity for {sup 90}Sr and alpha-emitting radionuclides compared to the current baseline material, MST. This paper describes recent results focused on further characterization of this material.

  9. A Mass Spectrometry Study of Isotope Separation in the Laser Plume

    NASA Astrophysics Data System (ADS)

    Suen, Timothy Wu

    Accurate quantification of isotope ratios is critical for both preventing the development of illicit weapons programs in nuclear safeguards and identifying the source of smuggled material in nuclear forensics. While isotope analysis has traditionally been performed by mass spectrometry, the need for in situ measurements has prompted the development of optical techniques, such as laser-induced breakdown spectroscopy (LIBS) and laser ablation molecular isotopic spectrometry (LAMIS). These optical measurements rely on laser ablation for direct solid sampling, but several past studies have suggested that the distribution of isotopes in the ablation plume is not uniform. This study seeks to characterize isotope separation in the laser plume through the use of orthogonal-acceleration time-of-flight mass spectrometry. A silver foil was ablated with a Nd:YAG at 355 nm at an energy of 50 muJ with a spot size of 71 mum, for a fluence of 1.3 J/cm2 and an irradiance of 250 MW/cm2. Flat-plate repellers were used to sample the plume, and a temporal profile of the ions was obtained by varying the time delay on the high-voltage pulse. A spatial profile along the axis of the plume was generated by changing the position of the sample, which yielded snapshots of the isotopic composition with time. In addition, the reflectron time-of-flight system was used as an energy filter in conjunction with the repellers to sample slices of the laser plasma orthogonal to the plume axis. Mass spectrometry of the plume revealed a fast ion distribution and a slow ion distribution. Measurements taken across the entire plume showed the fast 109Ag ions slightly ahead in both space and time, causing the 107Ag fraction to drop to 0.34 at 3 mus, 4 mm from the sample surface. Although measurements centered on the near side of the plume did not show isotope separation, the slow ions on the far side of the plume included much more 109Ag than 107Ag. In addition to examining the isotope content of the ablation

  10. Preparation and characterization of superparamagnetic molecularly imprinted polymers for selective adsorption and separation of vanillin in food samples.

    PubMed

    Ning, Fangjian; Peng, Hailong; Dong, Liling; Zhang, Zhong; Li, Jinhua; Chen, Lingxin; Xiong, Hua

    2014-11-19

    Novel water-compatible superparamagnetic molecularly imprinted polymers (M-MIPs) were prepared by coating superparamagnetic Fe3O4 nanoparticles with MIPs in a methanol-water reaction system. The M-MIPs were used for the selective adsorption and separation of vanillin from aqueous solution. The M-MIPs were characterized by X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), and scanning electron microscopy (SEM). Results indicated that a core-shell structure of M-MIPs was obtained by coating a layer of silica and MIPs on the surface of the Fe3O4 nanoparticles. The obtained M-MIPs possess a loose and porous structure and can be rapidly separated from the solution using a magnet. The adsorption experiments showed that the binding capacity of the M-MIPs was significantly higher than that of the superparamagnetic non-molecularly imprinted polymers (M-NIPs). Meanwhile, the adsorption of M-MIPs reached equilibrium within 100 min, and the apparent maximum adsorption quantity (Qmax) and dissociation constant (Kd) were 64.12 μmol g(-1) and 58.82 μmol L(-1), respectively. The Scatchard analysis showed that homogeneous binding sites were formed on the M-MIP surface. The recoveries of 83.39-95.58% were achieved when M-MIPs were used for the pre-concentration and selective separation of vanillin in spiked food samples. These results provided the possibility for the separation and enrichment of vanillin from complicated food matrices by M-MIPs.

  11. Coal liquefaction process streams characterization and evaluation: High performance liquid chromatography (HPLC) of coal liquefaction process streams using normal-phase separation with uv diode array detection

    SciTech Connect

    Clifford, D.J.; McKinney, D.E.; Hou, Lei; Hatcher, P.G.

    1994-01-01

    This study demonstrated the considerable potential of using two-dimensional, high performance liquid chromatography (HPLC) with normal-phase separation and ultraviolet (UV) diode array detection for the examination of filtered process liquids and the 850{degrees}F{sup {minus}} distillate materials derived from direct coal liquefaction process streams. A commercially available HPLC column (Hypersil Green PAH-2) provided excellent separation of the complex mixture of polynuclear aromatic hydrocarbons (PAHs) found in coal-derived process streams process. Some characteristics of the samples delineated by separation could be attributed to processing parameters. Mass recovery of the process derived samples was low (5--50 wt %). Penn State believes, however, that, improved recovery can be achieved. High resolution mass spectrometry and gas chromatography/mass spectrometry (GC/MS) also were used in this study to characterize the samples and the HPLC fractions. The GC/MS technique was used to preliminarily examine the GC-elutable portion of the samples. The GC/MS data were compared with the data from the HPLC technique. The use of an ultraviolet detector in the HPLC work precludes detecting the aliphatic portion of the sample. The GC/MS allowed for identification and quantification of that portion of the samples. Further development of the 2-D HPLC analytical method as a process development tool appears justified based on the results of this project.

  12. On-line separation and characterization of hyaluronan oligosaccharides derived from radical depolymerization

    PubMed Central

    Zhao, Xue; Yang, Bo; Li, Lingyun; Zhang, Fuming; Linhardt, Robert J.

    2013-01-01

    Hydroxyl radicals are widely implicated in the oxidation of carbohydrates in biological and industrial processes and are often responsible for their structural modification resulting in functional damage. In this study, the radical depolymerization of the polysaccharide hyaluronan was studied in a reaction with hydroxyl radicals generated by Fenton Chemistry. A simple method for isolation and identification of the resulting non-sulfated oligosaccharide products of oxidative depolymerization was established. Hyaluronan oligosaccharides were analyzed using ion-pairing reversed phase high performance liquid chromotography coupled with tandem electrospray mass spectrometry. The sequence of saturated hyaluronan oligosaccharides having even- and odd-numbers of saccharide units, afforded through oxidative depolymerization, were identified. This study represents a simple, effective ‘fingerprinting’ protocol for detecting the damage done to hyaluronan by oxidative radicals. This study should help reveal the potential biological outcome of reactive-oxygen radical-mediated depolymerization of hyaluronan. PMID:23768593

  13. Fundamental study on magnetic separation of aquatic organisms for preservation of marine ecosystem

    NASA Astrophysics Data System (ADS)

    Sakaguchi, F.; Akiyama, Y.; Izumi, Y.; Nishijima, S.

    2009-10-01

    Recently, destruction and disturbance of marine ecosystem have been caused by changes in global environment and transplants of farmed fishes and shellfishes. To solve the problems, water treatment techniques to kill or to remove aquatic organisms are necessary. In this study, application of magnetic separation for removal of the aquatic organisms was examined in order to establish the process with high-speed, compact device and low environmental load. Techniques of magnetic seeding and magnetic separation using superconducting magnet are important for high-speed processing of aquatic organisms. Magnetic seeding is to adhere separating object to the surface of ferromagnetic particles, and magnetic separation is to remove aquatic organisms with magnetic force. First, we confirmed the possibility of magnetic seeding of aquatic organisms, and then interaction between aquatic organisms and ferromagnetic particles was examined. Next, for practical application of magnetic separation system using superconducting magnet for removal of aquatic organisms, particle trajectories were simulated and magnetic separation experiment using superconducting magnet was performed in order to design magnetic separation system to achieve high separation efficiency.

  14. Localization and characterization of X chromosome inversion breakpoints separating Drosophila mojavensis and Drosophila arizonae.

    PubMed

    Cirulli, Elizabeth T; Noor, Mohamed A F

    2007-01-01

    Ectopic exchange between transposable elements or other repetitive sequences along a chromosome can produce chromosomal inversions. As a result, genome sequence studies typically find sequence similarity between corresponding inversion breakpoint regions. Here, we identify and investigate the breakpoint regions of the X chromosome inversion distinguishing Drosophila mojavensis and Drosophila arizonae. We localize one inversion breakpoint to 13.7 kb and localize the other to a 1-Mb interval. Using this localization and assuming microsynteny between Drosophila melanogaster and D. arizonae, we pinpoint likely positions of the inversion breakpoints to windows of less than 3000 bp. These breakpoints define the size of the inversion to approximately 11 Mb. However, in contrast to many other studies, we fail to find significant sequence similarity between the 2 breakpoint regions. The localization of these inversion breakpoints will facilitate future genetic and molecular evolutionary studies in this species group, an emerging model system for ecological genetics.

  15. A YAC contig map of plasmodium falciparum chromosome 4: Characterization of a DNA amplification between two recently separated isolates

    SciTech Connect

    Rubio, J.P.; Triglia, T.; Cowman, A.F.

    1995-03-20

    We have generated a physical map of Plasmodium falciparum chromosome 4 using yeast artificial chromosomes (YACs). The map is defined by a YAC contig spanning approximately 1.05 Mb, which has been restriction mapped to a resolution of 30 kb and is punctuated by 22 sequence-tagged sites. The physical information obtained has enabled us to compare and contrast the structure of chromosome 4 in detail between FCR3 and B8, two recently separated isolates of P. falciparum, leading to characterization of a novel chromosome polymorphism occurring in a subtelomeric region. Comparison of chromosomes 4 from 10 different isolates has shown that chromosome size polymorphisms are restricted to both subtelomeric regions. These analyses provide a high-resolution physical map that will be important to complement genetic analysis of this human pathogen. 42 refs., 6 figs., 1 tab.

  16. A protocol for exosome isolation and characterization: evaluation of ultracentrifugation, density-gradient separation, and immunoaffinity capture methods.

    PubMed

    Greening, David W; Xu, Rong; Ji, Hong; Tauro, Bow J; Simpson, Richard J

    2015-01-01

    Exosomes are 40-150 nm extracellular vesicles that are released from a multitude of cell types, and perform diverse cellular functions including intercellular communication, antigen presentation, and transfer of tumorigenic proteins, mRNA and miRNA. Exosomes are important regulators of the cellular niche, and their altered characteristics in many diseases, such as cancer, suggest their importance for diagnostic and therapeutic applications, and as drug delivery vehicles. Exosomes have been purified from biological fluids and in vitro cell cultures using a variety of strategies and techniques. In this chapter, we reveal the protocol and key insights into the isolation, purification and characterization of exosomes, distinct from shed microvesicles and apoptotic blebs. Using the colorectal cancer cell line LIM1863 as a cell model, a comprehensive evaluation of exosome isolation methods including ultracentrifugation (UC-Exos), OptiPrep™ density-based separation (DG-Exos), and immunoaffinity capture using anti-EpCAM-coated magnetic beads (IAC-Exos) were examined. All exosome isolation methodologies contained 40-150 nm vesicles based on electron microscopy, and positive for exosome markers (Alix, TSG101, HSP70) based on immunoblotting. This protocol employed a proteomic profiling approach to characterize the protein composition of exosomes, and label-free spectral counting to evaluate the effectiveness of each method in exosome isolation. Based on the number of MS/MS spectra identified for exosome markers and proteins associated with their biogenesis, trafficking, and release, IAC-Exos was shown to be the most effective method to isolate exosomes. However, the use of density-based separation (DG-Exos) provides significant advantages for exosome isolation when the use of immunoaffinity capture is limited (due to antibody availability and suitability of exosome markers).

  17. Magnetically separable Cu2O/chitosan-Fe3O4 nanocomposites: Preparation, characterization and visible-light photocatalytic performance

    NASA Astrophysics Data System (ADS)

    Cao, Chunhua; Xiao, Ling; Chen, Chunhua; Cao, Qihua

    2015-04-01

    A novel magnetically-separable visible-light-induced photocatalyst, Cu2O/chitosan-Fe3O4 nanocomposite (Cu2O/CS-Fe3O4 NC), was prepared via a facile one-step precipitation-reduction process by using magnetic chitosan chelating copper ions as precursor. The structure and properties of Cu2O/CS-Fe3O4 NCs were characterized by XRD, FT-IR, SEM, HRTEM, SAED, EDS, BET, VSM, XPS and UV-vis/DRS. The photocatalytic activity of Cu2O/CS-Fe3O4 NCs was evaluated by decolorization of reactive brilliant red X-3B (X-3B) under visible light irradiation. The characterization results indicated that Cu2O/CS-Fe3O4 NCs exhibited relatively large specific surface areas and special dimodal pore structure because Cu2O was wrapped in chitosan matrix embedded with Fe3O4 nanoparticles. The tight combination of magnetic Fe3O4 and semiconductor Cu2O through chitosan made the nanocomposites show good superparamagnetism and photocatalytic activity. It was found that X-3B could be decolorized more efficiently in acidic media than in neutral or alkaline media. The decolorization of X-3B was ascribed to the synergistic effect of photocatalysis and adsorption. Cu2O/CS-Fe3O4 NCs could be easily separated from the solution by an external magnet, and the decolorization rates of X-3B were still above 87% after five reaction cycles, indicating that Cu2O/CS-Fe3O4 NCs had excellent reusability and stability.

  18. Factors moderating children's adjustment to parental separation: findings from a community study in England.

    PubMed

    Cheng, Helen; Dunn, Judy; O'connor, Thomas G; Golding, Jean

    2006-04-01

    Research findings show that there is marked variability in children's response to parental separation, but few studies identify the sources of this variation. This prospective longitudinal study examines the factors modifying children's adjustment to parental separation in a community sample of 5,635 families in England. Children's behavioral/emotional problems were assessed when children were aged 47 and 81 months; marital quality, maternal depression, socioeconomic circumstances, and demographic variables were assessed prior to the separation from maternal report. Results indicated that 346 mothers separated from their partners in the 3-year period. Preseparation differences were found for measures of family process and parent risk factors, with effect sizes ranging from small to trivial. Parental separation was associated with a significant but modest increase in behavioral/emotional problems, independent of marital quality, maternal depression, socioeconomic circumstances, and demographic variables. Moderation analyses showed that children of cohabiting parents had a greater increase in adjustment problems following parental separation than children of married parents. Further research elucidating the factors that moderate children's adjustment to parental separation is needed to improve our understanding of who may most likely benefit from preventive interventions.

  19. Alternative dry separation of PM10 from soils for characterization by kinetic extraction: example of new Caledonian mining soils.

    PubMed

    Pasquet, Camille; Gunkel-Grillon, Peggy; Laporte-Magoni, Christine; Serres, Arnaud; Quiniou, Thomas; Rocca, François; Monna, Fabrice; Losno, Remi; van Oort, Folkert; Chateau, Carmela

    2016-12-01

    A simple new device for dry separation of fine particulate matter from bulk soil samples is presented here. It consists of a stainless steel tube along which a nitrogen flow is imposed, resulting in the displacement of particles. Taking into account particle transport, fluid mechanics, and soil sample composition, a tube 6-m long, with a 0.04-m diameter, was found best adapted for PM10 separation. The device rapidly produced several milligrams of particulate matter, on which chemical extractions with EDTA were subsequently performed to study the kinetic parameters of extractable metals. New Caledonian mining soils were chosen here, as a case-study. Although the easily extracted metal pool represents only 0.5-6.4 % of the total metal content for the elements studied (Ni, Co, Mn), the total concentrations are extremely high. This pool is therefore far from negligible, and can be troublesome in the environment. This dry technique for fine particle separation from bulk parent soil eliminates the metal-leaching risks inherent in wet filtration and should therefore ensure safe assessment of environmental quality in fine-textured, metal-contaminated soils.

  20. Molecular Dynamics Studies of Surface Difference Effect on Gas Separation by Zeolite Membranes

    NASA Astrophysics Data System (ADS)

    Mizukami, Koichi; Kobayashi, Yasunori; Morito, Hideaki; Takami, Seiichi; Kubo, Momoji; Belosludov, Rodion; Miyamoto, Akira

    2000-07-01

    The permeation of CO2/N2 gas mixture through zeolite membranes was investigated by molecular dynamics (MD) study. MD calculation successfully reproduced the experimental results of CO2/N2 separation by NaY membrane. Furthermore, the surface difference effect on gas separation was examined using the NaA zeolite (100) surface and its (111) surface. The CO2/N2 separation factor of the (111) surface was much lower than that of the (100) surface. This was caused by the difference in surface structure, since the pore structures of both models were the same.

  1. A Study of Laminar Separation Bubble in the Concave Region of an Airfoil Using Laser Velocimetry

    NASA Technical Reports Server (NTRS)

    Mangalam, Sivaramakrishnan; Meyers, James F.; Dagenhart, John R.; Harvey, William D.

    1985-01-01

    Laser velocimetry (LV) was used to study the nature of laminar separation bubbles in the concave region of a 1.83-meter airfoil model which was tested in the NASA Langley Low Turbulence Pressure Tunnel. Three component, coincident data from LV measurements including histograms of particle velocity, mean velocity profiles, turbulence intensity, and Reynolds stresses within the shear layer were used to determine the locations of laminar separation, transition, and turbulent reattachment. Boundary-layer parameters determined from velocity profiles were used to compare the results with existing empirical relations for describing the laminar separation bubble.

  2. The synthesis, characterization and application of iron oxide nanocrystals in magnetic separations for arsenic and uranium removal

    NASA Astrophysics Data System (ADS)

    Mayo, John Thomas

    Arsenic and uranium in the environment are hazardous to human health and require better methods for detection and remediation. Nanocrystalline iron oxides offer a number of advantages as sorbents for water purification and environmental remediation. First, highly uniform and crystalline iron oxide nanocrystals (nMAG) were prepared using thermal decomposition of iron salts in organic solutions; for the applications of interest in this thesis, a central challenge was the adaptation of these conventional synthetic methods to the needs of low infrastructure and economically disadvantaged settings. We show here that it is possible to form highly uniform and magnetically responsive nanomaterials using starting reagents and equipment that are readily available and economical. The products of this approach, termed the 'Kitchen Synthesis', are of comparable quality and effectiveness to laboratory materials. The narrow size distributions of the iron oxides produced in the laboratory synthesis made it possible to study the size-dependence of the magnetic separation efficiency of nanocrystals; generally as the diameter of particles increased they could be removed under lower applied magnetic fields. In this work we take advantage of this size-dependence to use magnetic separation as a tool to separate broadly distributed populations of magnetic materials. Such work makes it possible to use these materials in multiplexed separation and sensing schemes. With the synthesis and magnetic separation studies of these materials completed, it was possible to optimize their applications in water purification and environmental remediation. These materials removed both uranium and arsenic from contaminated samples, and had remarkably high sorption capacities --- up to 12 wt% for arsenic and 30 wt% for uranium. The contaminated nMAG is removed from the drinking water by either retention in a sand column, filter, or by magnetic separation. The uranium adsorption process was also utilized

  3. Synthesis and structural characterization of separate graphene oxide and reduced graphene oxide nanosheets

    NASA Astrophysics Data System (ADS)

    Aslam, M.; Kalyar, M. A.; Raza, Z. A.

    2016-10-01

    Graphene, being a unique carbon allotrope with a structure that is one atom thick, is known as a mysterious material in the current era due to its strange nature. It has attained global attention due to its amazing mechanical, electrical, thermal and optical properties. Recent progress has revealed that materials built with graphene can have a limitless impact on nanocomposites, electronic, optoelectronic and energy storage devices as well as chemical sensors. In the present study, graphite flakes were chemically oxidized in graphite oxide via the modified Hummers’ method, i.e. without adding sodium nitrate. The graphite oxide was exfoliated in distilled water by using an ultrasonic bath to fabricate graphene oxide nanosheets. The graphene was acquired through an inexpensive and large-scale production route to eliminate functional groups containing oxygen by using hydrazine monohydrate as a reducing agent. The reduced graphene oxide obtained through this route contained residual oxygen-functional groups which can act as active sites for gas molecular interaction and be used in a variety of applications like gas sensing. The prepared samples were analyzed using the dynamic light scattering technique, UV-visible spectroscopy, Fourier transform infrared spectroscopy, x-ray diffraction, scanning electron microscopy and atomic force microscopy.

  4. The association between parental separation during childhood and obesity in adulthood: a Danish twin study

    PubMed Central

    Kyvik, K. O.; Heitmann, B. L.; Vámosi, M. E.

    2016-01-01

    Summary Objective The purpose of this study was to examine if parental separation during childhood is associated with obesity in adulthood. Methods A co‐twin case–control study of 146 adult same‐sexed twin pairs with discordant body mass index (BMI) (i.e. one of the twins should have a BMI of 20–25 kg/m2, and the co‐twin's BMI ≥ 30 kg/m2) was selected from Danish Twin Registry (DTR). In total of 236 eligible twin individuals participated in the study. Childhood parental separation (defined as separation from one of the biological parents, regardless of the reason for separation) for at least one year prior to age 17 was self‐reported. The statistical analysis includes logistic and linear regression models using STATA 13.0. Results There were no differences in the odds of developing obesity in adulthood between the twin who stayed with a father and the co‐twin who was separated from him for at least 1 year prior to age 17 [OR = 1.22, 95%CI (0.46–3.34), p = 0.65]. Separation from a mother also showed no differences in the odds for developing obesity [OR = 0.90, 95%CI (0.32–2.46), p = 0.82]. Conclusions Because of the limited number of discordant twin pairs for childhood parental separation, we cannot provide evidence to suggest that separation from parents in childhood was associated with developing obesity in adulthood. Further studies of pooling discordant twins from several countries should be considered. PMID:28090349

  5. Factor Study for the Separator Plate of Mcfc Having Uniform Stiffness at Elevated Temperature

    NASA Astrophysics Data System (ADS)

    Lee, Sang-Wook; Kim, Jung-Hyun; Jun, Joong-Hwan

    A molten carbonate fuel cell (MCFC) is composed of several stacks of unit cells. A unit cell is composed of two electrodes and a matrix that is inserted between separator plates. Separator plates should properly contact the electrodes to reduce the electricity loss arising from contact resistance. To this end, a pressure of about 2 kgf/cm2 is usually applied on the top of the stack, which results in the separator plates being somewhat compacted. Furthermore, the stiffness of the separator plates becomes degraded at elevated temperatures due to softening of the plate materials. Therefore, a nonuniform temperature distribution across the separator plates induced by exothermic reactions of the oxidant and reactant gases leads to a non-uniform plate stiffness. This study has firstly evaluated the change in separator plate stiffness as temperature changes by applying pressure to the plates. Secondly, using the Taguchi method, several design factors that affect stiffness have been investigated to determine which has the most influence. Based on these results, a new design for the separators, which allows for uniform stiffness at elevated temperatures, has been proposed.

  6. Study of role of meniscus and viscous forces during liquid-mediated contacts separation

    NASA Astrophysics Data System (ADS)

    Dhital, Prabin

    Menisci may form between two solid surfaces with the presence of an ultra-thin liquid film. When the separation operation is needed, meniscus and viscous forces contribute to an adhesion leading stiction, high friction, possibly high wear and potential failure of the contact systems, for instance microdevices, magnetic head disks and diesel fuel injectors. The situation may become more pronounced when the contacting surfaces are ultra-smooth and the normal load is small. Various design parameters, such as contact angle, initial separation height, surface tension and liquid viscosity, have been investigated during liquid-mediated contact separation. However, how the involved forces will change roles for various liquid is of interest and is necessary to be studied. In this study, meniscus and viscous forces due to water and liquid lubricants during separation of two flat surfaces are studied. Previously established mathematical model for meniscus and viscous forces during flat on flat contact separation is simulated. The effect of meniscus and viscous force on critical meniscus area at which those forces change role is studied with different liquid properties for flat on flat contact surfaces. The roles of the involved forces at various meniscus areas are analyzed. Experiments are done in concerns to studying the effect of surface roughness on contact angle. The impact of liquid properties, initial separation heights and contact angle on critical meniscus area for different liquid properties are analyzed. The study provides a fundamental understanding of the forces of the separation process and its value for the design of interfaces. The effect of surface roughness and liquid properties on contact angle are studied.

  7. [Paleoclimatology studies for Yucca Mountain site characterization]. Final report

    SciTech Connect

    1996-05-03

    This report consists of two separate papers: Fernley Basin studies; and Influence of sediment supply and climate change on late Quaternary eolian accumulation patterns in the Mojave Desert. The first study involved geologic mapping of late Quaternary sediments and lacustrine features combined with precise control of elevations and descriptions of sediments for each of the major sedimentary units. The second paper documents the response of a major eolian sediment transport system in the east-central Mojave Desert: that which feeds the Kelso Dune field. Information from geomorphic, stratigraphic, and sedimentologic studies of eolian deposits and landforms is combined with luminescence dating of these deposits to develop a chronology of periods of eolian deposition. Both studies are related to site characterization studies of Yucca Mountain and the forecasting of rainfall patterns possible for the high-level radioactive waste repository lifetime.

  8. Preparation and Characterization of Hydrophilically Modified PVDF Membranes by a Novel Nonsolvent Thermally Induced Phase Separation Method.

    PubMed

    Hu, Ningen; Xiao, Tonghu; Cai, Xinhai; Ding, Lining; Fu, Yuhua; Yang, Xing

    2016-11-18

    In this study, a nonsolvent thermally-induced phase separation (NTIPS) method was first proposed to fabricate hydrophilically-modified poly(vinylidene fluoride) (PVDF) membranes to overcome the drawbacks of conventional thermally-induced phase separation (TIPS) and nonsolvent-induced phase separation (NIPS) methods. Hydrophilically-modified PVDF membranes were successfully prepared by blending in hydrophilic polymer polyvinyl alcohol (PVA) at 140 °C. A series of PVDF/PVA blend membranes was prepared at different total polymer concentrations and blend ratios. The morphological analysis via SEM indicated that the formation mechanism of these hydrophilically-modified membranes was a combined NIPS and TIPS process. As the total polymer concentration increased, the tensile strength of the membranes increased; meanwhile, the membrane pore size, porosity and water flux decreased. With the PVDF/PVA blend ratio increased from 10:0 to 8:2, the membrane pore size and water flux increased. The dynamic water contact angle of these membranes showed that the hydrophilic properties of PVDF/PVA blend membranes were prominently improved. The higher hydrophilicity of the membranes resulted in reduced membrane resistance and, hence, higher permeability. The total resistance Rt of the modified PVDF membranes decreased significantly as the hydrophilicity increased. The irreversible fouling related to pore blocking and adsorption fouling onto the membrane surface was minimal, indicating good antifouling properties.

  9. Preparation and Characterization of Hydrophilically Modified PVDF Membranes by a Novel Nonsolvent Thermally Induced Phase Separation Method

    PubMed Central

    Hu, Ningen; Xiao, Tonghu; Cai, Xinhai; Ding, Lining; Fu, Yuhua; Yang, Xing

    2016-01-01

    In this study, a nonsolvent thermally-induced phase separation (NTIPS) method was first proposed to fabricate hydrophilically-modified poly(vinylidene fluoride) (PVDF) membranes to overcome the drawbacks of conventional thermally-induced phase separation (TIPS) and nonsolvent-induced phase separation (NIPS) methods. Hydrophilically-modified PVDF membranes were successfully prepared by blending in hydrophilic polymer polyvinyl alcohol (PVA) at 140 °C. A series of PVDF/PVA blend membranes was prepared at different total polymer concentrations and blend ratios. The morphological analysis via SEM indicated that the formation mechanism of these hydrophilically-modified membranes was a combined NIPS and TIPS process. As the total polymer concentration increased, the tensile strength of the membranes increased; meanwhile, the membrane pore size, porosity and water flux decreased. With the PVDF/PVA blend ratio increased from 10:0 to 8:2, the membrane pore size and water flux increased. The dynamic water contact angle of these membranes showed that the hydrophilic properties of PVDF/PVA blend membranes were prominently improved. The higher hydrophilicity of the membranes resulted in reduced membrane resistance and, hence, higher permeability. The total resistance Rt of the modified PVDF membranes decreased significantly as the hydrophilicity increased. The irreversible fouling related to pore blocking and adsorption fouling onto the membrane surface was minimal, indicating good antifouling properties. PMID:27869711

  10. Study of the separation efficiency of a demister vane with response surface methodology.

    PubMed

    Zhao, Jianzhi; Jin, Baosheng; Zhong, Zhaoping

    2007-08-17

    Numerical simulations of a demister vane with various geometries and operating conditions were performed to study the separation efficiency. The numerical solutions were carried out using commercial CFD code Fluent 6.1. A prediction model of the separation efficiency was obtained based on response surface methodology by means of the statistical software program Minitab V14. The results show that not only the vane spacing and flue gas velocity, but also vane height (including height of curve and upright region) and vane turning angles, play an important role in influencing the separation efficiency. Compared with some experimental and simulative conclusions, the results indicate that present prediction model can estimate the effects of different geometries and operation conditions on the separation efficiency, and can direct the optimum design of demisters.

  11. Numerical study on the suppression of shock induced separation on the non-adiabatic wall

    NASA Astrophysics Data System (ADS)

    Lee, Doug-Bong

    2000-12-01

    A numerical model is constructed to simulate the interaction of supersonic ( M=2.4) oblique shock wave / turbulent boundary layer on a strongly heated wall. The heated wall temperature is two times higher than the adiabatic wall temperature and the shock wave is strong enough to induce boundary layer separation. The turbulence model is Spalart-Allmaras model. The comparison of the wall pressure distribution with the experimental data ensures the validity of this numerical model. The effect of strong wall heating enlarges the separation region upstream and downstream. In order to eliminate the separation, wall bleeding is applied at the shock foot position. As a result of the parametric study, the best position of the bleeding slot is selected. The position of the bleeding is very important for the separation suppression. If the bleeding is applied upstream of shock foot, then separation reoccurs after the bleeding slot. If the bleeding is applied downstream of shock foot, the upstream boundary layer is little influenced and still separated. The bleeding vent width is about same as the upstream boundary layer thickness and suction mass flow is 20 to 80 % of the flow rate in the upstream boundary layer. The bleeding mass flow rate is very sensitive to the bleeding vent position if we fix the vent outlet pressure. The final configuration of the shock reflection pattern approaches to the non-viscous value when wall bleeding is applied at the shock impinging point.

  12. Impaired neurogenesis of the dentate gyrus is associated with pattern separation deficits: A computational study.

    PubMed

    Faghihi, Faramarz; Moustafa, Ahmed A

    2016-09-01

    The separation of input patterns received from the entorhinal cortex (EC) by the dentate gyrus (DG) is a well-known critical step of information processing in the hippocampus. Although the role of interneurons in separation pattern efficiency of the DG has been theoretically known, the balance of neurogenesis of excitatory neurons and interneurons as well as its potential role in information processing in the DG is not fully understood. In this work, we study separation efficiency of the DG for different rates of neurogenesis of interneurons and excitatory neurons using a novel computational model in which we assume an increase in the synaptic efficacy between excitatory neurons and interneurons and then its decay over time. Information processing in the EC and DG was simulated as information flow in a two layer feed-forward neural network. The neurogenesis rate was modeled as the percentage of new born neurons added to the neuronal population in each time bin. The results show an important role of an optimal neurogenesis rate of interneurons and excitatory neurons in the DG in efficient separation of inputs from the EC in pattern separation tasks. The model predicts that any deviation of the optimal values of neurogenesis rates leads to different decreased levels of the separation deficits of the DG which influences its function to encode memory.

  13. Parental separation in childhood and self-reported psychological health: A population-based study.

    PubMed

    Lindström, Martin; Rosvall, Maria

    2016-12-30

    The aim of the present study is to investigate associations between parental separation/divorce during childhood, and self-reported psychological health, adjusting for social capital, social support, civil status and economic stress in childhood. A cross-sectional public health survey was conducted in the autumn of 2012 in Scania, southern Sweden, with a postal questionnaire with 28,029 participants aged 18-80. Associations between parental separation/divorce during childhood and self-reported psychological health (GHQ12) were investigated using logistic regressions. A 16.1% proportion of all men 22.4% of all women reported poor psychological health. Among men, 20.4% had experienced parental separation during childhood until age 18 years, the corresponding prevalence among women was 22.3%. Parental separation/divorce in childhood was significantly associated with poor self-rated psychological health among men who had experienced parental separation/divorce at ages 0-4, and among women with this experience at ages 0-4, 10-14 and 15-18. These significant associations remained throughout the multiple analyses. The results support the notion that the experience of parental separation/divorce in childhood may influence psychological health in adulthood, particularly if it is experienced in the age interval 0-4 years.

  14. Experimental study on the flow separation and self-excited oscillation phenomenon in a rectangular duct

    NASA Astrophysics Data System (ADS)

    Xiong, Bing; Wang, Zhen-Guo; Fan, Xiao-Qiang; Wang, Yi

    2017-04-01

    To study the characteristics of flow separation and self-excited oscillation of a shock train in a rectangular duct, a simple test case has been conducted and analyzed. The high-speed Schlieren technique and high-frequency pressure measurements have been adopted to collect the data. The experimental results show that there are two separation modes in the duct under M3 incoming condition. The separation mode switch has great effects on the flow effects, such as the pressure distribution, the standard deviation distribution and so on. The separation mode switch can be judged by the history of pressure standard deviation. When it comes to the self-excited oscillation of a shock train, the frequency contents in the undisturbed region, the intermittent region, and the separated bubble have been compared. It was found that the low-frequency disturbance induced by the upstream shock foot motions can travel downstream and the frequency will be magnified by the separation bubble. The oscillation of the small shock foot and the oscillation of the large shock foot are associated with each other rather than oscillating independently.

  15. A Charge Separation Study to Enable the Design of a Complete Muon Cooling Channel

    SciTech Connect

    Yoshikawa, C.; Ankenbrandt, Charles M.; Johnson, Rolland P.; Derbenev, Yaroslav; Morozov, Vasiliy; Neuffer, David; Yonehara, K.

    2013-12-01

    The most promising designs for 6D muon cooling channels operate on a specific sign of electric charge. In particular, the Helical Cooling Channel (HCC) and Rectilinear RFOFO designs are the leading candidates to become the baseline 6D cooling channel in the Muon Accelerator Program (MAP). Time constraints prevented the design of a realistic charge separator, so a simplified study was performed to emulate the effects of charge separation on muons exiting the front end of a muon collider. The output of the study provides particle distributions that the competing designs will use as input into their cooling channels. We report here on the study of the charge separator that created the simulated particles.

  16. a Conceptual Design Study of a Next Generation Separator for the In-Flight Separation of Superheavy Nuclei

    NASA Astrophysics Data System (ADS)

    Münzenberg, Gottfried; Gupta, Mohini; Geissel, Hans; Heinz, Sophia; Hofmann, Sigurd; Plass, Wolfgang R.; Scheidenberger, Christoph; Weick, Helmut; Winkler, Martin

    2013-06-01

    After more than 25 years of the successful operation of SHIP in heavy-and superheavy element research, it is due time for the development of a next-generation in-flight separator for fusion and transfer products, primarily for heavy and superheavy elements. This work is triggered by new developments including accelerators for beams of highest intensity, the availability of strong beams of radioactive isotopes at near Coulomb barrier energies, and the recent developments for efficient ion catcher-cooler systems with the capability of mass identification and measurement.

  17. Separation and/or divorce sexual assault in rural Ohio: preliminary results of an exploratory study.

    PubMed

    DeKeseredy, Walter S; Joseph, Carolyn

    2006-03-01

    A rapidly growing social scientific literature shows that many women are at great risk of being killed, beaten, or psychologically abused when they exit or try to leave their marital and/or cohabiting partners. However, less than a handful of studies have examined male-to-female sexual assaults during and after separation or divorce. Furthermore, the bulk of the limited empirical work on this problem was done in urban areas. Thus, the main objective of this article is to help fill two major research gaps by presenting the preliminary results of an ongoing exploratory study of separation and/or divorce sexual assault in rural Ohio.

  18. Separation and characterization of nitrated variants of the major birch pollen allergen by CZE-ESI-μTOF MS

    PubMed Central

    Gusenkov, Sergey; Ackaert, Chloé; Stutz, Hanno

    2013-01-01

    A CZE-ESI-TOF MS method has been optimized for the separation and identification of nitrated variants of the major birch pollen allergen from Betula verrucosa, isoform 1a (Bet v 1a). In-house nitration of recombinant Bet v 1a was done by peroxynitrite. As a BGE, 10 mmol/L ammonium bicarbonate with pH 7.50 provided best resolution. Nebulizer gas pressure and sheath liquid flow rate of 0.4 bar and 6 μL/min, respectively, maintained CZE selectivity and constituted stable electrospray conditions. A sheath liquid composition of 75% v/v methanol with 0.1% v/v formic acid in ultrapure water resulted in highest signal intensities. Alternatively, methanol could be replaced by 50% v/v isopropanol. Two modified allergen products derived from reaction mixtures that contained different amounts of the nitration reagent were compared by the elaborated CZE-ESI-TOF MS method. Up to twelve different Bet v 1a variants with one- to sixfold nitration could be distinguished. Several allergen fractions of equivalent nitration grade were resolved. Their different migration times indicate site-specific nitration with concomitant differences in pI and maybe also in hydrodynamic radius. The method allows for a characterization of in-house nitrated allergen samples that are intended for testing the postulated enhanced allergenicity of nitrated Bet v 1a variants. PMID:23857337

  19. Colloidal Defect-Free Silicalite-1 Single Crystals: Preparation, Structure Characterization, Adsorption, and Separation Properties for Alcohol/Water Mixtures.

    PubMed

    Zhou, Han; Mouzon, Johanne; Farzaneh, Amirfarrokh; Antzutkin, Oleg N; Grahn, Mattias; Hedlund, Jonas

    2015-08-04

    In this work, colloidal silicalite-1 single crystals are for the first time synthesized using fluoride as mineralizing agent at near neutral pH. SEM, TEM, DLS, XRD, solid-state (29)Si MAS NMR, and adsorption/desorption experiments using nitrogen, water, n-butanol, and ethanol as adsorbates were used to characterize the crystals. The single crystals have a platelike habit with a length of less than 170 nm and an aspect ratio (length/width) of about 1.2, and the thickness of the crystals is less than 40 nm. Compared with silicalite-1 crystals grown using hydroxide as mineralizing agent, the amount of structural defects in the lattice is significantly reduced and the hydrophobicity is increased. Membrane separation and adsorption results show that the synthesized defect-free crystals present high selectivity to alcohols from alcohol/water mixtures. The n-butanol/water adsorption selectivities were ca. 165 and 14 for the defect-free crystals and a reference sample containing defects, respectively, illustrating the improvement in n-butanol/water selectivity by eliminating the polar silanol defects.

  20. Overcoming Coulombic Traps: Geometry and Electronic Characterizations of Light-Induced Separated Spins at the Bulk Heterojunction Interface.

    PubMed

    Kobori, Yasuhiro; Miura, Taku

    2015-01-02

    Recent progress is overviewed on experimental elucidations of fundamental molecular functions of the light-energy conversions by the photoactive layers of the organic photovoltalic (OPV) cells by means of the time-resolved electron paramagnetic resonance spectroscopy. Positions and orientations of the unpaired electrons and electronic coupling matrix elements are clarified in photoinduced, primary charge-separated (CS) states. Connections between the molecular geometries and the electronic couplings have been characterized for the initial CS states to elucidate how the structure, orbital delocalization, and molecular libration play roles on exothermic carrier dissociation via a vibrationally relaxed charge-transfer complex with prevention of the energy-wasting charge recombination. Superior functions to biological molecules are presented for the efficient photocurrent generations induced by orbital delocalization and by shallow trap depths at polymer-stacking domains. The above structural and electronic characteristics of the primary electron-hole pairs are essential to evaluations, designs, and developments of the efficient solar cells using organic molecules.

  1. X2000 advanced avionics characterization study

    NASA Technical Reports Server (NTRS)

    Day, L.; Meyer, D.; Nicolich, N.; Steele, R.; Uchenik, I.; Vines, K.

    2003-01-01

    The characterization study has shown that adjustments in an application's data accesses can easily create a performance difference of three or more times in actual applications. In general, by iterating over a small portion of a data set rather than its entirety, execution can remain within cache thereby producing a performance increase. Additionally, the approaches used in performing I/O can make a major performance difference.

  2. Is early separation anxiety a specific precursor of panic disorder-agoraphobia? A community study.

    PubMed

    Silove, D; Harris, M; Morgan, A; Boyce, P; Manicavasagar, V; Hadzi-Pavlovic, D; Wilhelm, K

    1995-03-01

    The present study aimed to examine memories of early separation anxiety symptoms in a community sample of women at heightened risk to neurotic disorder. The chief finding was that subjects with a lifetime history of panic disorder-agoraphobia (PD-Ag) returned statistically higher scores on a retrospective measure of early separation anxiety compared to subjects with either generalized anxiety or other phobic disorders, a result which was not accounted for by differences in neuroticism or General Health Questionnaire scores. Although limited by its retrospective design and the problem of co-morbidity in subclassifying the anxiety disorders, the present study does provide added support for the hypothesis--endorsed by DSM-III-R--that there is a developmental link between early separation anxiety and panic disorder.

  3. Liquid chromatographic separation in metal-organic framework MIL-101: a molecular simulation study.

    PubMed

    Hu, Zhongqiao; Chen, Yifei; Jiang, Jianwen

    2013-02-05

    A molecular simulation study is reported to investigate liquid chromatographic separation in metal-organic framework MIL-101. Two mixtures are considered: three amino acids (Arg, Phe, and Trp) in aqueous solution and three xylene isomers (p-, m-, and o-xylene) dissolved in hexane. For the first mixture, the elution order is found to be Arg > Phe > Trp. The hydrophilic Arg has the strongest interaction with the polar mobile phase (water) and the weakest interaction with the stationary phase (MIL-101), and thus transports at the fastest velocity. Furthermore, Arg forms the largest number of hydrogen bonds with water and possesses the largest hydrophilic solvent-accessible surface area. For the second mixture, the elution order is p-xylene > m-xylene > o-xylene, consistent with available experimental observation. With the largest polarity as compared to p- and m-xylenes, o-xylene interacts the most strongly with the stationary phase and exhibits the slowest transport velocity. For both mixtures, the underlying separation mechanism is elucidated from detailed energetic and structural analysis. It is revealed that the separation can be attributed to the cooperative solute-solvent and solute-framework interactions. This simulation study, for the first time, provides molecular insight into liquid chromatographic separation in a MOF and suggests that MIL-101 might be an interesting material for the separation of industrially important liquid mixtures.

  4. An experimental study of flow separation over a flat plate with 2D transverse grooves

    NASA Astrophysics Data System (ADS)

    Jones, Emily Michelle

    Nature has long been an inspiration for research in engineering. In particular, the biological surfaces of aquatic swimmers have been studied for their potential as drag reducing surfaces. The hydrodynamic benefit of riblets, or grooves embedded parallel to the flow, which appear on many aquatic biological surfaces, have been well documented and implemented in practical engineering applications. However the skin of dolphins is embedded with grooves that run perpendicular to the flow of water over their bodies. It is theorized that the transverse grooves present on dolphin skin trap vortices between them, creating a partial slip condition over the surface and inducing turbulence augmentation in the boundary layer, thus controlling boundary layer separation over the dolphin's skin. Similarly, sharks are covered with scales that are flexible at the base and capable of bristling, forming grooves running transverse to the flow. It is theorized that the scales bristle when encountering a reversing flow, thereby trapping vortices between the scales and, similarly, delaying boundary layer separation. In an attempt to test this hypothesis and study these affects, a spinning cylinder was used in a water tunnel to induce separation over a flat plate with 2 mm, rectangular transverse grooves and sinusoidal grooves of similar scaling. The results were compared to tripped, turbulent boundary layer separation occurring over a flat plate without grooves using time-resolved particle image velocimetry. The strength of the adverse pressure gradient was varied, and the observed delay in flow separation and other affects upon the boundary layer are discussed.

  5. Separation and characterization of the aldehydic products of lipid peroxidation stimulated by ADP-Fe2+ in rat liver microsomes.

    PubMed Central

    Esterbauer, H; Cheeseman, K H; Dianzani, M U; Poli, G; Slater, T F

    1982-01-01

    1. Methods using t.l.c. and high-pressure liquid chromatography (h.p.l.c.) have been used to separate the complex variety of substances possessing a carbonyl function that are produced during lipid peroxidation. 2. The major type of lipid peroxidation studied was the ADP-Fe2+-stimulated peroxidation of rat liver microsomal phospholipids. Preliminary separation of the polar and non-polar products was achieved by t.l.c.: further separation and identification of individual components was performed by h.p.l.c. Estimations were performed on microsomal pellets and the supernatant mixture after incubation of microsomes for 30 min at 37 degrees C. 3. The polar fraction was larger than the non-polar fraction when expressed as nmol of carbonyl groups/g of liver. In the non-polar supernatant fraction the major contributors were n-alkanals (31% of the total), alpha-dicarbonyl compounds (22%) and 4-hydroxyalkenals (37%) with the extraction method used. 4. Major individual contributors to the non-polar fraction were found to be propanal, 4-hydroxynonenal, hexanal and oct-2-enal. Other components identified include butanal, pent-2-enal, hex-2-enal, hept-2-enal, 4-hydroxyoctenal and 4-hydroxyundecenal. The polar carbonyl fraction was less complex than the non-polar fraction, although the identities of the individual components have not yet been established. 5. Since these carbonyl compounds do not react significantly in the thiobarbituric acid reaction, which largely demonstrates the presence of malonaldehyde, it is concluded that considerable amounts of biologically reactive carbonyl derivatives are released in lipid peroxidation and yet may not be picked up by the thiobarbituric acid reaction. PMID:7159389

  6. Separation and characterization of phenolic compounds from dry-blanched peanut skins by liquid chromatography-electrospray ionization mass spectrometry.

    PubMed

    Ma, Yuanyuan; Kosińska-Cagnazzo, Agnieszka; Kerr, William L; Amarowicz, Ryszard; Swanson, Ruthann B; Pegg, Ronald B

    2014-08-22

    A large variety of phenolic compounds, including phenolic acids (hydroxybenzoic acids, hydroxycinnamic acids, and their esters), stilbenes (trans-resveratrol and trans-piceatannol), flavan-3-ols (e.g., (-)-epicatechin, (+)-catechin, and their polymers {the proanthocyanidins, PACs}), other flavonoids (e.g., isoflavones, flavanols, and flavones, etc.) and biflavonoids (e.g., morelloflavone), were identified in dry-blanched peanut skins (PS) by this study. High-performance liquid chromatography (HPLC) coupled with electrospray ionization mass spectrometry (ESI-MS(n)) was applied to separate and identify the phenolic constituents. Reversed-phase HPLC was employed to separate free phenolic compounds as well as PAC monomers, dimers, and trimers. PACs with a degree of polymerization (DP) of >4 were chromatographed via hydrophilic interaction liquid chromatography (HILIC). Tentative identification of the separated phenolics was based solely on molecular ions and MS(n) fragmentation patterns acquired by ESI-MS in the negative-ion mode. The connection sequence of PAC oligomers (DP <5) could be deduced mainly through characteristic quinone methide (QM) cleavage ions. When the DP reached 6, only a proportion of the flavan-3-ols could be ascertained in the PACs because of the extremely complicated fragmentation patterns involved. The identification of free phenolic acids, stilbenes, and flavonoids was achieved by authentic commercial standards and also by published literature data. Quantification was performed based on peak areas of the UV (free phenolic compounds) or fluorescence (PACs) signals from the HPLC chromatograms and calibration curves of commercial standards. Overall, PS contain significantly more PACs compared to free phenolic compounds.

  7. Self-propelled rods exhibit a phase-separated state characterized by the presence of active stresses and the ejection of polar clusters

    NASA Astrophysics Data System (ADS)

    Weitz, Sebastian; Deutsch, Andreas; Peruani, Fernando

    2015-07-01

    We study collections of self-propelled rods (SPR) moving in two dimensions for packing fractions less than or equal to 0.3. We find that in the thermodynamical limit the SPR undergo a phase transition between a disordered gas and a novel phase-separated system state. Interestingly, (global) orientational order patterns—contrary to what has been suggested—vanish in this limit. In the found novel state, the SPR self-organize into a highly dynamical, high-density, compact region—which we call aggregate—which is surrounded by a disordered gas. Active stresses build inside aggregates as a result of the combined effect of local orientational order and active forces. This leads to the most distinctive feature of these aggregates: constant ejection of polar clusters of SPR. This novel phase-separated state represents a novel state of matter characterized by large fluctuations in volume and shape, related to mass ejection, and exhibits positional as well as orientational local order. SPR systems display new physics unseen in other active matter systems.

  8. On-line separator for {gamma}-spectroscopic studies at FLNR JINR

    SciTech Connect

    Popeko, A. G.; Belozerov, A. V.; Chepigin, V. I.; Kabachenko, A. P.; Malyshev, O. N.; Shutov, A. V.; Svirikhin, A. I.; Yeremin, A. V.; Dorvaux, O.; Hauschild, K.; Korichi, A.; Lopez-Martens, A.

    2007-05-22

    A JINR - IN2P3 collaboration project named 'GABRIELA' aimed at the nuclear spectroscopy of transfermium elements using the recoil separator VASSILISSA was launched in 2004 at JINR in Dubna. In the close future the FLNR cyclotron U400M will go through a major upgrade with the goal to deliver heavy ion beams at the energy close to the Coulomb barrier in a new experimental area. Here we report about R and D of the new separator for spectroscopic studies which we plan to install at the beam of the modernized accelerator and which will allow to realize new possibilities of the GABRIELA project.

  9. On-line separator for γ-spectroscopic studies at FLNR JINR

    NASA Astrophysics Data System (ADS)

    Popeko, A. G.; Belozerov, A. V.; Chepigin, V. I.; Dorvaux, O.; Hauschild, K.; Kabachenko, A. P.; Korichi, A.; Lopez-Martens, A.; Malyshev, O. N.; Shutov, A. V.; Svirikhin, A. I.; Yeremin, A. V.

    2007-05-01

    A JINR — IN2P3 collaboration project named "GABRIELA" aimed at the nuclear spectroscopy of transfermium elements using the recoil separator VASSILISSA was launched in 2004 at JINR in Dubna. In the close future the FLNR cyclotron U400M will go through a major upgrade with the goal to deliver heavy ion beams at the energy close to the Coulomb barrier in a new experimental area. Here we report about R&D of the new separator for spectroscopic studies which we plan to install at the beam of the modernized accelerator and which will allow to realize new possibilities of the GABRIELA project.

  10. Study on magnetic separation for decontamination of cesium contaminated soil by using superconducting magnet

    NASA Astrophysics Data System (ADS)

    Igarashi, Susumu; Nomura, Naoki; Mishima, Fumihito; Akiyama, Yoko

    2014-09-01

    The accident of Fukushima Daiichi nuclear power plant caused the diffusion of radioactive cesium over the wide area. We examined the possibility of applying magnetic separation method using the superconducting magnet, which can process a large amount of the soil in high speed, to the soil decontamination and volume reduction of the radioactive cesium contaminated soil. Clay minerals are classified as 2:1 and 1:1 types by the difference of their layer structures, and these types of minerals are respectively paramagnetic and diamagnetic including some exception. It is known that most of the radioactive cesium is strongly adsorbed on the clay, especially on 2:1 type clay minerals. It is expected that the method which can separate only 2:1 type clay minerals selectively from the mixture clay minerals can enormously contribute to the volume reduction of the contaminated soil. In this study, the components in the clay before and after separation were evaluated to estimate the magnetic separation efficiency by using X-ray diffraction. From the results, the decontamination efficiency and the volume reduction ratio were estimated in order to examine the appropriate separation conditions for the practical decontamination of the soil.

  11. Are Attitudes toward Writing and Reading Separable Constructs? A Study with Primary Grade Children

    ERIC Educational Resources Information Center

    Graham, Steve; Berninger, Virginia; Abbott, Robert

    2012-01-01

    This study examined whether attitude toward writing is a unique and separable construct from attitude toward reading for young beginning writers. Participants were 128 first-grade children (70 girls and 58 boys) and 113 third-grade students (57 girls and 56 boys). We individually administered to each child a 24-item attitude measure that contained…

  12. Removal of Separable Organic From Tank 241-C-103 Scoping Study

    SciTech Connect

    KOCH, M.R.

    2000-05-16

    This study is based on previous evaluations/proposals for removing the floating organic layer in C-103. A practical method is described with assumptions, cost and schedule estimates, and risks. Proposed operational steps include bulk organic removal, phase separation, organic washing and offsite disposal, followed by an in-situ polishing process.

  13. Spontaneous separation of large-spin Fermi gas in the harmonic trap: a density functional study

    PubMed Central

    Sun, Zongli; Gu, Qiang

    2016-01-01

    The component separation of the trapped large-spin Fermi gas is studied within density functional theory. The ground state and ferromagnetic transition in the gas, with and without the spin mixing collision, are calculated. In the absence of spin mixing, two patterns of separation are observed as the interaction between atoms increases, whereas only one of them corresponds to a ferromagnetic transition. The phase diagram suggests that the pattern which the system chooses depends on the interaction strength in the collision channels. With the presence of spin mixing, the distribution of phase region changes because of the interplay between different collision channels. Specifically, the spin exchange benefits the FM transition, while it suppresses the component separation of CS-II pattern. PMID:27549012

  14. A study of the effects of numerical dissipation on the calculation of supersonic separated flows

    NASA Technical Reports Server (NTRS)

    Kuruvila, G.; Anderson, J. D., Jr.

    1985-01-01

    An extensive investigation of the effect of numerical dissipation on the calculation of supersonic, separated flow over a rearward-facing step is carried out. The complete two-dimensional Navier-Stokes equations are solved by means of MacCormack's standard explicit, unsplit, time-dependent, finite difference method. A fourth-order numerical dissipation term is added explicitly. The magnitude of this term is progressively varied, and its consequences on the flowfield calculations are identified and studied. For a cold-wall, heat transfer case, numerical dissipation had a major effect on the results, particularly in the separated region. However, rather dramatically for an adiabatic wall case, numerical dissipation had virtually no effect on the results. The role of grid size on both the influence of numerical dissipation, and on the overall accuracy of the separated flow solutions is discussed.

  15. Numerical study of particle deposition and scaling in dust exhaust of cyclone separator

    NASA Astrophysics Data System (ADS)

    Xu, W. W.; Li, Q.; Zhao, Y. L.; Wang, J. J.; Jin, Y. H.

    2016-05-01

    The solid particles accumulation in the dust exhaust cone area of the cyclone separator can cause the wall wear. This undoubtedly prevents the flue gas turbine from long period and safe operation. So it is important to study the mechanism how the particles deposited and scale on dust exhaust cone area of the cyclone separator. Numerical simulations of gas-solid flow field have been carried out in a single tube in the third cyclone separator. The three-dimensionally coupled computational fluid dynamic (CFD) technology and the modified Discrete Phase Model (DPM) are adopted to model the gas-solid two-phase flow. The results show that with the increase of the operating temperature and processing capacity, the particle sticking possibility near the cone area will rise. The sticking rates will decrease when the particle diameter becomes bigger.

  16. SEPARATION AND CHARACTERIZATION OF TETROL METABOLITES OF BENZO[A]PYRENE-DNA ADDUCTS USING HPLC AND SOLID-MATRIX ROOM TEMPERATURE LUMINESCENCE. (R824100)

    EPA Science Inventory

    Abstract

    Four tetrols of benzo[a]pyrene-DNA adducts were separated using reversed-phase high performance liquid chromatography. Chromatographic fractions containing a given tetrol were readily characterized with solid-matrix room temperature luminescence techniques. So...

  17. Synthesis, separation, and characterization of amphiphilic sulfated oligosaccharides enabled by reversed-phase ion pairing LC and LC-MS methods.

    PubMed

    Fenner, Amanda M; Kerns, Robert J

    2011-12-13

    Synthesis of amphiphilic oligosaccharides is problematic because traditional methods for separating and purifying oligosaccharides, including sulfated oligosaccharides, are generally not applicable to working with amphiphilic sugars. We report here RPIP-LC and LC-MS methods that enable the synthesis, separation, and characterization of amphiphilic N-arylacyl O-sulfonated aminoglycosides, which are being pursued as small-molecule glycosaminoglycan mimics. The methods described in this work for separating and characterizing these amphiphilic saccharides are further applied to a number of uses: monitoring the progression of sulfonation reactions with analytical RP-HPLC, characterizing sulfate content for individual molecules with ESI-MS, determining the degree of sulfation for products having mixed degrees of sulfation with HPLC and LC-MS, and purifying products with benchtop C18 column chromatography. We believe that the methods described here will be broadly applicable to enabling the synthesis, separation, and characterization of amphiphilic, sulfated, and phosphorylated oligosaccharides and other types of molecules substituted to varying degrees with both anionic and hydrophobic groups.

  18. Nanoscale Phase Separation In Epitaxial Cr-Mo and Cr-V Alloy Thin Films Studied Using Atom Probe Tomography. Comparison Of Experiments And Simulation

    SciTech Connect

    Devaraj, Arun; Kaspar, Tiffany C.; Ramanan, Sathvik; Walvekar, Sarita K.; Bowden, Mark E.; Shutthanandan, V.; Kurtz, Richard J.

    2014-11-21

    Tailored metal alloy thin film-oxide interfaces generated using molecular beam epitaxial (MBE) deposition of alloy thin films on a single crystalline oxide substrate can be used for detailed studies of irradiation damage response on the interface structure. However presence of nanoscale phase separation in the MBE grown alloy thin films can impact the metal-oxide interface structure. Due to nanoscale domain size of such phase separation it is very challenging to characterize by conventional techniques. Therefor laser assisted atom probe tomography (APT) was utilized to study the phase separation in epitaxial Cr0.61Mo0.39, Cr0.77Mo0.23, and Cr0.32V0.68 alloy thin films grown by MBE on MgO(001) single crystal substrates. Statistical analysis, namely frequency distribution analysis and Pearson coefficient analysis of experimental data was compared with similar analyses conducted on simulated APT datasets with known extent of phase separation. Thus the presence of phase separation in Cr-Mo films, even when phase separation was not clearly observed by x-ray diffraction, and the absence of phase separation in the Cr-V film were thus confirmed.

  19. Nanoscale phase separation in epitaxial Cr-Mo and Cr-V alloy thin films studied using atom probe tomography: Comparison of experiments and simulation

    SciTech Connect

    Devaraj, A.; Ramanan, S.; Walvekar, S.; Bowden, M. E.; Shutthanandan, V.; Kaspar, T. C.; Kurtz, R. J.

    2014-11-21

    Tailored metal alloy thin film-oxide interfaces generated using molecular beam epitaxy (MBE) deposition of alloy thin films on a single crystalline oxide substrate can be used for detailed studies of irradiation damage response on the interface structure. However, the presence of nanoscale phase separation in the MBE grown alloy thin films can impact the metal-oxide interface structure. Due to nanoscale domain size of such phase separation, it is very challenging to characterize by conventional techniques. Therefore, laser assisted atom probe tomography (APT) was utilized to study the phase separation in epitaxial Cr{sub 0.61}Mo{sub 0.39}, Cr{sub 0.77}Mo{sub 0.23}, and Cr{sub 0.32}V{sub 0.68} alloy thin films grown by MBE on MgO(001) single crystal substrates. Statistical analysis, namely frequency distribution analysis and Pearson coefficient analysis of experimental data was compared with similar analyses conducted on simulated APT datasets with known extent of phase separation. Thus, the presence of phase separation in Cr-Mo films, even when phase separation was not clearly observed by x-ray diffraction, and the absence of phase separation in the Cr-V film were confirmed.

  20. Non-ionic, thermo-responsive DEA/DMA nanogels: synthesis, characterization, and use for DNA separations by microchip electrophoresis.

    PubMed

    Lu, Xihua; Sun, Mingyun; Barron, Annelise E

    2011-05-15

    Thermo-responsive polymer "nanogels" (crosslinked hydrogel particles with sub-100 nm diameters) are intriguing for many potential applications in biotechnology and medicine. There have been relatively few reports of electrostatically neutral, thermosensitive nanogels comprising a high fraction of hydrophilic co-monomer. Here we demonstrate the syntheses and characterization of novel, non-ionic nanogels based on random N,N-diethylacrylamide (DEA)/N,N-dimethylacrylamide (DMA) copolymers, made by free-radical, surfactant-free dispersion polymerization. The volume-phase transition temperatures of these DEA/DMA nanogels are strongly affected by co-monomer composition, providing a way to "tune" the phase transition temperature of these non-ionic nanogels. While DEA nanogels (comprising no DMA) can be obtained at 70 °C by standard emulsion precipitation, DEA/DMA random co-polymer nanogels can be obtained only in a particular range of temperatures, above the initial phase transition temperature and below the critical precipitation temperature of the DEA/DMA copolymer, controlled by co-monomer composition. Increasing percentages of DMA in the nanogels raises the phase transition temperature, and attenuates and broadens it as well. We find that concentrated DEA/DMA nanogel dispersions are optically clear at room temperature. This good optical clarity was exploited for their use in a novel DNA sieving matrix for microfluidic chip electrophoresis. An ultrafast, high-efficiency dsDNA separation was achieved in less than 120 s for dsDNA ranging from 75 bp to 15,000 bp.

  1. Characterization and application of a semi-automated separation and analysis technique for polychlorinated biphenyls in Great Lakes wildlife

    SciTech Connect

    Williams, L.L.

    1993-01-01

    Polychlorinated hydrocarbons (PCHs) are toxic, persistent compounds in the environment. The non-ortho substituted PCB congeners comprise most of the Ah receptor-mediated PCH toxicity in aquatic systems. The proportion of the most toxic congeners to the total concentration of PCBs is suspected to vary in the environment, but these congeners are difficult to quantify. The studies described here focus on the development and use of a semi-automated separation of the non-ortho substituted congeners from interferences using porous graphitic carbon (PGC). The PGC method developed it faster and uses less solvent than previous separations based on carbon columns. This method is both precise and accurate, with no discernable interferences. Results obtained from this method can be used with TCDD equivalency factors (TEFs) to calculate TCDD-equivalents (TEQs) derived from PCBs. The PGC method was used successfully to measure PCB congeners in eggs of fish-eating birds. Variability in TEQ and PCB concentrations among eggs within a double-crested cormorant colony was investigated. No significant differences in concentrations of PCBs to TEQs were observed among eggs from nests with different reproductive outcomes; therefore, concentrations of TEQs and PCBs could not be related to reproductive success of nests within a single colony. TEQs determined in an H4IIE bioassay for EROD activity were significantly greater than TEQs calculated from concentrations of PCB congeners. In another study, concentrations of TEQs and PCBs in red-breasted merganser eggs collected 13 years apart were compared. Concentrations of TEQs and PCBs declined significantly between 1977 and 1990, but the ratio of TEQ to total PCBH did not change.

  2. Guide to collagen characterization for biomaterial studies.

    PubMed

    Abraham, Leah C; Zuena, Erin; Perez-Ramirez, Bernardo; Kaplan, David L

    2008-10-01

    The structure and remodeling of collagen in vivo is critical to the pathology and healing of many human diseases, as well as to normal tissue development and regeneration. In addition, collagen matrices in the form of fibers, coatings, and films are used extensively in biomaterial and biomedical applications. The specific properties of these matrices, both in terms of physical and chemical characteristics, have a direct impact on cellular adhesion, spreading, and proliferation rates, and ultimately on the rate and extent of new extracellular matrix formation in vitro or in vivo. In recent studies, it has also been shown that collagen matrix structure has a major impact on cell and tissue outcomes related to cellular aging and differentiation potential. Collagen structure is complex because of both diversity of source materials, chemistry, and structural hierarchy. With such significant impact of collagen features on biological outcomes, it becomes essential to consider an appropriate set of analytical tools, or guide, so that collagens attained from commercial vendors are characterized in a comparative manner as an integral part of studies focused on biological parameters. The analysis should include as a starting point: (a) structural detail-mainly focused on molecular mass, purity, helical content, and bulk thermal properties, (b) chemical features-mainly focused on surface elemental analysis and hydrophobicity, and (c) morphological features at different length scales. The application of these analytical techniques to the characterization of collagen biomaterial matrices is critical in order to appropriately correlate biological responses from different studies with experimental outcomes in vitro or in vivo. As a case study, the analytical tools employed for collagen biomaterial studies are reviewed in the context of collagen remodeling by fibroblasts. The goal is to highlight the necessity of understanding collagen biophysical and chemical features as a

  3. Characterization and Beneficiation Studies of a Low Grade Bauxite Ore

    NASA Astrophysics Data System (ADS)

    Rao, D. S.; Das, B.

    2014-10-01

    A low grade bauxite sample of central India was thoroughly characterized with the help of stereomicroscope, reflected light microscope and electron microscope using QEMSCAN. A few hand picked samples were collected from different places of the mine and were subjected to geochemical characterization studies. The geochemical studies indicated that most of the samples contain high silica and low alumina, except a few which are high grade. Mineralogically the samples consist of bauxite (gibbsite and boehmite), ferruginous mineral phases (goethite and hematite), clay and silicate (quartz), and titanium bearing minerals like rutile and ilmenite. Majority of the gibbsite, boehmite and gibbsitic oolites contain clay, quartz and iron and titanium mineral phases within the sample as inclusions. The sample on an average contains 39.1 % Al2O3 and 12.3 % SiO2, and 20.08 % of Fe2O3. Beneficiation techniques like size classification, sorting, scrubbing, hydrocyclone and magnetic separation were employed to reduce the silica content suitable for Bayer process. The studies indicated that, 50 % by weight with 41 % Al2O3 containing less than 5 % SiO2 could be achieved. The finer sized sample after physical beneficiation still contains high silica due to complex mineralogical associations.

  4. Analysis of Mtwo rotary instrument separation during endodontic therapy: a retrospective clinical study.

    PubMed

    Wang, Nan-Nan; Ge, Jiu-Yu; Xie, Si-Jing; Chen, Ge; Zhu, Min

    2014-11-01

    To analyze the incidence of instrument separation (IS) and the factors influencing it, when associated with Mtwo rotary system (VDW, Munich, Germany) during endodontic therapy. A retrospective study involving a total of 24,108 root canals (11,036 endodontic treated teeth) was conducted at Nanjing Stomatology Hospital between January 2011 and March 2013. The information included were tooth type, root canal curvature, number of fractured instruments, length of the separated fragments, and the distance from broken tip to apex. The incidence of IS was observed to be 2.2 % according to the number of teeth and 1.0 % according to the number of root canals. Many of the separated fragments were 2-4 mm in length and the mean length was 3.07 ± 1.46 mm, and 78.4 % of fractures occurred in the apex. The mean length of separated fragments in severely curved canals was maximum, while ultra-severe curved canals was observed to be minimum. Mtwo instruments demonstrated an extremely low fracture rate during endodontic therapy. Molar teeth (especially lower molars) and the degree of canal curvature had a significant effect on the incidence of IS.

  5. Semi-industrial experimental study on bauxite separation using a cell-column integration process

    NASA Astrophysics Data System (ADS)

    Zhang, Ning-ning; Zhou, Chang-chun; Cong, Long-fei; Cao, Wen-long; Zhou, You

    2016-01-01

    The cyclonic-static micro-bubble flotation column (FCSMC) is a highly efficient mineral processing equipment. In this study, a cell-column (FCSMC) integration process was investigated for the separation of bauxite and its feasibility was analyzed on a theoretical basis. The properties of low-grade bauxite ore from Henan Province, China were analyzed. Parameters such as reagent dosage, scraping bubble time, and pressure of the circulating pump during the sorting process were investigated and optimized to improve the flotation efficiency. On the basis of these parameters, continuous separation experiments were conducted. Bauxite concentrate with an aluminum-to-silicon (A/S) mass ratio of 6.37 and a 77.63wt% recovery rate were achieved via a flow sheet consisting of "fast flotation using a flotation cell, one roughing flotation and one cleaning flotation using flotation columns". Compared with the full-flotation-cells process, the cell-column integration process resulted in an increase of the A/S ratio by 0.41 and the recovery rate by 17.58wt%. Cell-column integration separation technology represents a new approach for the separation of middle-to-low-grade bauxite ore.

  6. Feasibility study of the separation of chlorinated films from plastic packaging wastes

    SciTech Connect

    Reddy, Mallampati Srinivasa; Yamaguchi, Takefumi; Okuda, Tetsuji; Tsai, Tsung-Yueh; Nakai, Satoshi; Nishijima, Wataru; Okada, Mitsumasa

    2010-04-15

    This study describes the possible separation of chlorinated plastic films (PVC and PVDC) from other heavy plastic packaging waste (PPW) by selective twist formation and gravity separation. Twists formation was mechanically induced in chlorinated plastic films, whereas twist formation did not occur in PS and PET films. After twist formation, all the films had the apparent density of less than 1.0 g/cm{sup 3} and floated in water even though the true density was more than 1.0 g/cm{sup 3}. However, the apparent density of the PS and the PET films increased with agitation to more than 1.0 g/cm{sup 3}, whereas that of chlorinated plastic films was kept less than 1.0 g/cm{sup 3}. The main reason would be the air being held inside the chlorinated plastic films which was difficult to be removed by agitation. Simple gravity separation after twist formation was applied for artificial film with 10 wt.% of the chlorinated films and real PPW films with 9 wt.% of the chlorinated films. About 76 wt.% of the artificial PPW films and 75 wt.% of real PPW films after the removal of PP and PE were recovered as settling fraction with 4.7 wt.% and 3.0 wt.% of chlorinated plastic films, respectively. These results indicate that simple gravity separation process after twist formation can be used to reduce the chlorinated plastic concentration from mixed heavy PPW films.

  7. Feasibility study of the separation of chlorinated films from plastic packaging wastes.

    PubMed

    Reddy, Mallampati Srinivasa; Yamaguchi, Takefumi; Okuda, Tetsuji; Tsai, Tsung-Yueh; Nakai, Satoshi; Nishijima, Wataru; Okada, Mitsumasa

    2010-04-01

    This study describes the possible separation of chlorinated plastic films (PVC and PVDC) from other heavy plastic packaging waste (PPW) by selective twist formation and gravity separation. Twists formation was mechanically induced in chlorinated plastic films, whereas twist formation did not occur in PS and PET films. After twist formation, all the films had the apparent density of less than 1.0g/cm(3) and floated in water even though the true density was more than 1.0g/cm(3). However, the apparent density of the PS and the PET films increased with agitation to more than 1.0g/cm(3), whereas that of chlorinated plastic films was kept less than 1.0g/cm(3). The main reason would be the air being held inside the chlorinated plastic films which was difficult to be removed by agitation. Simple gravity separation after twist formation was applied for artificial film with 10wt.% of the chlorinated films and real PPW films with 9wt.% of the chlorinated films. About 76wt.% of the artificial PPW films and 75wt.% of real PPW films after the removal of PP and PE were recovered as settling fraction with 4.7wt.% and 3.0wt.% of chlorinated plastic films, respectively. These results indicate that simple gravity separation process after twist formation can be used to reduce the chlorinated plastic concentration from mixed heavy PPW films.

  8. Pseudo-stationary separation materials for highly parallel separations.

    SciTech Connect

    Singh, Anup K.; Palmer, Christopher

    2005-05-01

    Goal of this study was to develop and characterize novel polymeric materials as pseudostationary phases in electrokinetic chromatography. Fundamental studies have characterized the chromatographic selectivity of the materials as a function of chemical structure and molecular conformation. The selectivities of the polymers has been studied extensively, resulting in a large body of fundamental knowledge regarding the performance and selectivity of polymeric pseudostationary phases. Two polymers have also been used for amino acid and peptide separations, and with laser induced fluorescence detection. The polymers performed well for the separation of derivatized amino acids, and provided some significant differences in selectivity relative to a commonly used micellar pseudostationary phase. The polymers did not perform well for peptide separations. The polymers were compatible with laser induced fluorescence detection, indicating that they should also be compatible with chip-based separations.

  9. The use of coarse, separable, condensed-phase organic carbon particles to characterize desorption resistance of polycyclic aromatic hydrocarbons in contaminated sediments

    SciTech Connect

    Chai, Y.Z.; Kochetkov, A.; Reible, D.D.

    2007-07-15

    Physical separations were employed to characterize the source of desorption-resistant behavior for polycyclic aromatic hydrocarbons (PAHs) in laboratory- and field-contaminated sediments. Size and density separation of laboratory-contaminated sediments did not effectively separate the amorphous-phase (volatile) and condensed-phase (nonvolatile) organic carbon as measured by thermal oxidation at 375 {sup o}C. These separations also did not result in sediment fractions with significantly different desorption characteristics as measured by apparent partition coefficients. Coarse particles from a field-contaminated sediment from Utica Harbor (UH; Utica, NY, USA), however, could be directly separated into sandy fractions and organic fractions that were composed of woody organic matter, charcoal or charred vegetative matter, and coal-like and coal-cinder particles. Chemical analysis showed that coal-like (glassy, nonporous) and coal-cinder (porous, sintered) particles exhibited very high PAH concentrations and high apparent partition coefficients. These particles also exhibited significantly higher condensed-phase (nonvolatile) organic carbon contents as defined by thermal oxidation at 375{sup o}C. The apparent partition coefficients of PAHs in the coal-cinder particles were a good indication of the apparent partition coefficients in the desorption-resistant fraction of UH sediment, indicating that the coarse particles provided a reasonable characterization of the desorption-resistance phenomena in these sediments even though the coarse fractions represented less than 25% of the organic carbon in the whole sediment.

  10. Herbs and spices: characterization and quantitation of biologically-active markers for routine quality control by multiple headspace solid-phase microextraction combined with separative or non-separative analysis.

    PubMed

    Sgorbini, Barbara; Bicchi, Carlo; Cagliero, Cecilia; Cordero, Chiara; Liberto, Erica; Rubiolo, Patrizia

    2015-01-09

    Herbs and spices are used worldwide as food flavoring, thus determination of their identity, origin, and quality is mandatory for safe human consumption. An analysis strategy based on separative (HS-SPME-GC-MS) and non-separative (HS-SPME-MS) approaches is proposed for the volatile fraction of herbs and spices, for quality control and to quantify the aromatic markers with a single analysis directly on the plant material as such. Eight-to-ten lots of each of the following herbs/spices were considered: cloves (Syzygium aromaticum (L.) Merr. & Perry), American peppertree (Schinus molle L.), black pepper and white pepper (Piper nigrum L.), rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.) and thyme (Thymus vulgaris L.). Homogeneity, origin, and chemotypes of the investigated lots of each herb/spice were defined by fingerprinting, through statistical elaboration with principal component analysis (PCA). Characterizing aromatic markers were directly quantified on the solid matrix through multiple headspace extraction-HS-SPME (MHS-SPME). Reliable results were obtained with both separative and non-separative methods (where the latter were applicable); the two were in full agreement, RSD% ranging from 1.8 to 7.7% for eugenol in cloves, 2.2-18.4% for carvacrol+thymol in thyme, and 3.1-16.8% for thujones in sage.

  11. Supercooling transition in phase separated manganite thin films: An electrical transport study

    SciTech Connect

    Singh, Sandeep; Kumar, Pawan; Siwach, P. K.; Singh, H. K.; Tyagi, Pawan Kumar

    2014-05-26

    The impact of variation in the relative fractions of the ferromagnetic metallic and antiferromagnetic/charge ordered insulator phases on the supercooling/superheating transition in strongly phase separated system, La{sub 5/8−y}Pr{sub y}Ca{sub 3/8}MnO{sub 3} (y ≈ 0.4), has been studied employing magnetotransport measurements. Our study clearly shows that the supercooling transition temperature is non-unique and strongly depends on the magneto-thermodynamic path through which the low temperature state is accessed. In contrast, the superheating transition temperature remains constant. The thermo-magnetic hysteresis, the separation of the two transitions and the associated resistivity, all are functions of the relative fraction of the coexisting phases.

  12. A flow separation study over a shortfin mako shark pectoral fin

    NASA Astrophysics Data System (ADS)

    Bradshaw, Michael; Lang, Amy; Wahidi, Redha; Smith, Drew; Motta, Philip

    2011-11-01

    Many animals possess performance enhancing mechanisms, such as the denticles found on the skin of the shortfin mako shark (Isurus oxyrinchus). The shortfin mako, one of the fastest sharks on the planet, is covered by small, tooth-like scales that vary in bristling capability. Previous biological findings have shown that the scales increase in flexibility from the leading to trailing edge over the pectoral fin. As this fin is a primary control surface, the scale bristling may provide a mechanism for separation control that leads to decreased drag and increased maneuverability. Such findings can potentially lead to the development of similar micro-scale mechanisms to improve the efficiency of aerospace design. A left pectoral fin (71 cm span) was tested in a water tunnel facility under static and dynamic conditions. Digital Particle Image Velocimetry (DPIV) was used to characterize the flow over the fin. Various angles of attack at two speeds were tested (Re of 44,500 and 68,000). Two chord-wise locations, approximately mid-span where three-dimensional effects were minimized, were viewed to analyze the flow. After the initial testing, the fin was painted to eliminate the effect of the scales and retested to observe flow separation. Supported by REU SITE EEC grant number 1062611.

  13. Microgravity electrophoresis: A study of the factors that affect free-fluid separation

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Electrophoresis experiments have been performed in the microgravity environment of the Space Shuttle. Test particles (fixed human and rabbit erythrocytes) migrated as expected in a static column and test macromolecules (human serum albumin, ovalbumin, hemoglobin A, and Pneumococcus polysaccharide 6B) migrated as expected in a continuous flow apparatus. The concentrations studied exceeded those that can be used in free-fluid separation and purification processes at unit gravity.

  14. In situ studies of phase separation and crystallization directed by Marangoni instabilities during spin-coating.

    PubMed

    Toolan, Daniel T W; Pullan, Nikki; Harvey, Michael J; Topham, Paul D; Howse, Jonathan R

    2013-12-23

    Results of a pioneering study are presented in which for the first time, crystallization, phase separation and Marangoni instabilities occurring during the spin-coating of polymer blends are directly visualized, in real-space and real-time. The results provide exciting new insights into the process of self-assembly, taking place during spin-coating, paving the way for the rational design of processing conditions, to allow desired morphologies to be obtained.

  15. Design and characterization of materials with microphase-separated surface patterns for screening osteoblast response to adhesion

    NASA Astrophysics Data System (ADS)

    Wingkono, Gracy A.

    Combinatorial techniques have changed the paradigm of materials research by allowing efficient screening of complex materials problems with large, multidimensional parameter spaces. The focus of this thesis is to demonstrate combinatorial methods (CM) and high-throughput methods (HTM) applied to biomaterials design, characterization, and screening. In particular, this work focuses on screening the effects of biomaterial surface features on adherent bone cell cultures. Polymeric biomaterials were prepared on two-dimensional combinatorial libraries that systematically varied the size and shape of chemically-distinct microstructural patterns. These libraries were generated from blends of biodegradable polyurethanes and polyesters prepared with thickness, composition and temperature gradient techniques. Characterization and screening were performed with high-throughput optical and fluorescence microscopy. A unique advance of this work is the application of data mining techniques to identify the controlling structural features that affect cell behavior from among the myriad variety of metrics from the microscope images. Libraries were designed to exhibit chemically-distinct cell-adhesive versus non-adhesive microstructural domains that improve library performance compared to previous implementations that had employed only modest chemical differences. Improving adhesive contrast should minimize combination of effects of chemistry and physical structure, making data interpretation simpler. To accomplish this, a method of blending and crosslinking cell-non-adhesive poly(ethylene glycol) (PEG) with cell-adhesive poly(·-caprolactone) (PCL) was developed. The behavior of MC3T3-E1 osteoblast cells cultured on the PCL-PEG libraries were observed, equivalent to thousands of distinct chemistries and microstructures. Cell spreading area, shape, and density upon adhesion on surface patterns are observed in this study. Characterization of the surface library and screening of

  16. Core-shell magnetic nanoparticles: a comparative study based on silica and polydopamine coating for magnetic bio-separation platforms.

    PubMed

    Sahin, Ferat; Turan, Eylem; Tumturk, Hayrettin; Demirel, Gokhan

    2012-12-07

    Core-shell magnetic nanoparticles (MNPs) offer tremendous opportunities in a large range of applications in biomedicine due to their superior magnetic properties, biocompatibility and suitability for modification. In most cases, these characteristic features are determined by their shell chemistry and morphology. Herein, we demonstrate a comparative study of silica and polydopamine (PDOP) coating onto MNP surfaces based on synthesis, characterization and usage in a bio-separation platform. It was found that monodispersed MNPs may be easily obtained on silica coating of varying shell thickness, whereas a continuous PDOP layer observed around the MNPs prevents the formation of the dispersed form. On the other hand, PDOP coated MNPs exhibited better superparamagnetic behavior and biological modification ability compared to the silica coated form.

  17. Investigation and characterization of liquid two-phase systems for the separation of crystal mixtures by interfacial partitioning.

    PubMed

    Hoeben, Martijn A; van Hee, Pim; van der Lans, Rob G J M; Kwant, Gerard; van der Wielen, Luuk A M

    2006-03-05

    The interfacial partitioning behavior of ampicillin and phenylglycine crystals in different two-phase systems has been investigated. The two-phase systems employed are water/dodecane, water/1-butanol, and water/pentane/methanol. By means of partition experiments and microscopic imaging, it has been shown that the mechanism of separation strongly depends on the choice of the two-phase system. While water/dodecane features a mechanism of sheer competitive adsorption at the interface, separation in water/1-butanol is mainly due to partitioning into both liquid phases, leading to a higher degree of separation. Experiments with water/pentane/methanol have illustrated the large potential of three-component systems, as slight variations in the composition can have large effects on the separation.

  18. Characterization of Diesel Fuel by Chemical Separation Combined with Capillary Gas Chromatography (GC) Isotope Ratio Mass Spectrometry (IRMS)

    SciTech Connect

    Harvey, Scott D.; Jarman, Kristin H.; Moran, James J.; Sorensen, Christina M.; Wright, Bob W.

    2011-09-15

    The purpose of this study was to perform a preliminary investigation of compound-specific isotope analysis (CSIA) of diesel fuels to evaluate whether the technique could distinguish between the diesel samples from different sources/locations. The ability to differentiate or correlate diesel samples could be valuable for detecting fuel tax evasion schemes. Two fractionation techniques were used to isolate the n-alkanes from the fuel. Both δ13C and δD values for the n-alkanes were then determined by CSIA in each sample. Plots of δD versus δ13C with sample n-alkane points connected in order of increasing carbon number gave well separated clusters with characteristic shapes for each sample. Principal components analysis (PCA) with δ13C, δD, or combined δ13C and δD data on the yielded scores plots that could clearly differentiate the samples, thereby demonstrating the potential of this approach for fingerprinting fuel samples using the δ13C and δD values.

  19. Molecular dynamics study of contact mechanics: contact area and interfacial separation from small to full contact

    NASA Astrophysics Data System (ADS)

    Yang, Chunyan; Persson, Bo

    2008-03-01

    We report a molecular dynamics study of the contact between a rigid solid with a randomly rough surface and an elastic block with a flat surface. We study the contact area and the interfacial separation from small contact (low load) to full contact (high load). For small load the contact area varies linearly with the load and the interfacial separation depends logarithmically on the load [1-4]. For high load the contact area approaches to the nominal contact area (i.e., complete contact), and the interfacial separation approaches to zero. The present results may be very important for soft solids, e.g., rubber, or for very smooth surfaces, where complete contact can be reached at moderate high loads without plastic deformation of the solids. References: [1] C. Yang and B.N.J. Persson, arXiv:0710.0276, (to appear in Phys. Rev. Lett.) [2] B.N.J. Persson, Phys. Rev. Lett. 99, 125502 (2007) [3] L. Pei, S. Hyun, J.F. Molinari and M.O. Robbins, J. Mech. Phys. Sol. 53, 2385 (2005) [4] M. Benz, K.J. Rosenberg, E.J. Kramer and J.N. Israelachvili, J. Phy. Chem. B.110, 11884 (2006)

  20. An Experimental Study of Flow Separation Control by Shortfin Mako Shark Skin

    NASA Astrophysics Data System (ADS)

    Afroz, Farhana; Lang, Amy; Motta, Philip; Habegger, Maria

    2013-11-01

    The shortfin mako shark (Isurus oxyrinchus) is a fast swimmer and has incredible turning agility. Shark skin is covered with flexible scales and this bristling capability may result in a unique Boundary Layer Control (BLC) method to reduce drag. It is hypothesized that scales bristle when the flow above it is reversed, and between the bristled scales embedded micro-vortices form in the cavities which induce boundary layer mixing and aid in delaying flow separation. To testify this hypothesis, samples of mako shark skin have been tested in a water tunnel under various strengths of adverse pressure gradient (APG). Laminar and turbulent separation over shark skin was studied experimentally using Time-Resolved Digital Particle Image Velocimetry (TR-DPIV) system, where the APG was generated and varied using a rotating cylinder. Then shark skin results were compared with that of a flat plate data for a given amount of APG. The study reveals that shark skin is capable of controlling both laminar and turbulent flow separation. Support under NSF grant 0932352 is gratefully acknowledged. First author Farhana Afroz was also supported by a scholarship through the Alabama EPSCoR Graduate Research Scholars Program.

  1. Simulation of π0-γ Separation Study for Proposed CMS Forward Electromagnetic Calorimeter

    NASA Astrophysics Data System (ADS)

    Roy, Ashim; Jain, Shilpi; Banerjee, Sunanda; Bhattacharya, Satyaki; Majumder, Gobinda

    2016-10-01

    The Forward Electromagnetic Calorimeter of the CMS detector is going to be upgraded in the high luminosity running as the energy of the present Electromagnetic Calorimeter (PbWO4) will degrade in the high luminosity (luminosity 1034 cm -2 s -1) running due to extensive radiation (hadron flux 1013neutrons cm,-2). Shashlik Electromagnetic Calorimeter which consists of alternate layers of 1.5 mm LYSO(Ce) crystal plates and 2.5 mm Tungsten absorbers, was a proposal for high luminosity running. One of the performance points for any electromagnetic calorimeter is the ability to separate π0 s from true photons, since final states with photons are a clean and one of the most important final states in proton-proton collisions at the LHC. The objective of this project is to study the possibility of π0 and γ separation in the Shashlik detector using Multivariate Analysis (MVA) technique.

  2. Experimental parametric study of jet vortex generators for flow separation control

    NASA Technical Reports Server (NTRS)

    Selby, Gregory

    1991-01-01

    A parametric wind-tunnel study was performed with jet vortex generators to determine their effectiveness in controlling flow separation associated with low-speed turbulence flow over a two-dimensional rearward-facing ramp. Results indicate that flow-separation control can be accomplished, with the level of control achieved being a function of jet speed, jet orientation (with respect to the free-stream direction), and orifice pattern (double row of jets vs. single row). Compared to slot blowing, jet vortex generators can provide an equivalent level of flow control over a larger spanwise region (for constant jet flow area and speed). Dye flow visualization tests in a water tunnel indicated that the most effective jet vortex generator configurations produced streamwise co-rotating vortices.

  3. A study of multistage/multifunction column for fine particle separation

    SciTech Connect

    Chiang, Shiao-Hung

    1996-07-01

    The overall objective of the research program is to explore the potential application of a new invention involving a multistage column equipped with vortex-inducing loop-flow contactors (hereafter referred to as the multistage column) for fine coal cleaning process. The research work will identify the design parameters and their effects on the performance of the separation process. The results of this study will provide an engineering basis for further development of this technology in coal cleaning and in the general areas of fluid/particle separation. In the last quarter, we investigated the fine coal beneficiation behaviors in the multistage column and the conventional column. In this quarter, we have initiated the wastewater treatment tests program to verify the multifunction features of the multistage column. We also performed data analysis of the bubble sizes using a model based on the unified proportionality equation. 7 refs., 10 figs., 7 tabs.

  4. Numerical Study of Pillar Shapes in Deterministic Lateral Displacement Microfluidic Arrays for Spherical Particle Separation.

    PubMed

    Wei, Jianhui; Song, Hui; Shen, Zaiyi; He, Ying; Xu, Xianzhi; Zhang, Yong; Li, Bing Nan

    2015-09-01

    Deterministic lateral displacement (DLD) arrays containing shaped pillars have been found to be more effective in biomedical sample separation. This study aims to numerically investigate the interplay between particles and microfluidic arrays, and to find out the key factors in determining the critical size of a DLD device with shaped pillars. A new formula is thus proposed to estimate the critical size for spherical particle separation in this kind of new DLD microfluidic arrays. The simulation results show that both rectangular and I-shaped arrays have considerably smaller critical sizes. The ratio of sub-channel widths is also found to play an important role in reducing the critical sizes. This paves a valuable way toward designing high-performance DLD microfluidic arrays.

  5. Experimental Study of the Effects of Periodic Unsteady Wakes on Flow Separation in Low Pressure Turbines

    NASA Technical Reports Server (NTRS)

    Ozturk, Burak; Schobeiri, Meinhard T.

    2009-01-01

    The present study, which is the first of a series of investigations of low pressure turbine (LPT) boundary layer aerodynamics, is aimed at providing detailed unsteady boundary layer flow information to understand the underlying physics of the inception, onset, and extent of the separation zone. A detailed experimental study on the behavior of the separation zone on the suction surface of a highly loaded LPT-blade under periodic unsteady wake flow is presented. Experimental investigations were performed on a large-scale, high-subsonic unsteady turbine cascade research facility with an integrated wake generator and test section unit. Blade Pak B geometry was used in the cascade. The wakes were generated by continuously moving cylindrical bars device. Boundary layer investigations were performed using hot wire anemometry at Reynolds number of 110,000, based on the blade suction surface length and the exit velocity, for one steady and two unsteady inlet flow conditions, with the corresponding passing frequencies, wake velocities, and turbulence intensities. The reduced frequencies cover the entire operation range of LP-turbines. In addition to the unsteady boundary layer measurements, blade surface pressure measurements were performed at Re = 50,000, 75,000, 100,000, 110,000, and 125,000. For each Reynolds number, surface pressure measurements are carried out at one steady and two periodic unsteady inlet flow conditions. Detailed unsteady boundary layer measurement identifies the onset and extension of the separation zone as well as its behavior under unsteady wake flow. The results, presented in ensemble-averaged and contour plot forms, help to understand the physics of the separation phenomenon under periodic unsteady wake flow.

  6. Development of Multiscale Materials in Microfluidic Devices: Case Study for Viral Separation from Whole Blood

    NASA Astrophysics Data System (ADS)

    Surawathanawises, Krissada

    Separation and concentration of nanoscale species play an important role in various fields such as biotechnology, nanotechnology and environmental science. Inevitably, the separation efficiency strongly affects the quality of downstream detections or productions. Innovations in materials science that can separate bionanoparticles efficiently and do not require complex setups, reagents or external fields are highly demanded. This work focuses on developing new materials for the affinity separation of bio-nanoparticles such as viruses or macromolecules from a complex mixture, such as whole blood. To enhance the interaction between target nanoparticles and the capture bed, methods to produce porous matrices with a uniform pore size matching the dimension of targets are studied. Furthermore, regarding viral separation from whole blood, macroporous materials are further patterned into microarrays to allow multiscale separation. Considering the needs in resource-limited settings, these materials are integrated with microfluidic technologies to reduce the volume of samples and reagents, simplify operating processes, and enable the use of inexpensive and portable components. Beyond the application of viral separation as demonstrated in the work, the fundamental study of macroporous material formation and transport in these materials also shed light to the separation of many other nanospecies in multiscale materials. Specifically, two macroporous materials, based on template synthesis, are created in this work. The first type employs porous anodic aluminum oxide (AAO) films as the template to create hexagonal arrays of nanoposts. However, pore sizes and interpore distances (cell size) of ordered porous AAO films are limited by the conventional fabrication process. Moreover, the process usually yields defective pore morphologies and large pore and cell size distributions. To overcome these limitations, a patterning method using nanobead indentation on aluminum substrate

  7. 40 CFR 792.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 33 2012-07-01 2012-07-01 false Physical and chemical characterization... A Study § 792.135 Physical and chemical characterization studies. (a) All provisions of the GLPs shall apply to physical and chemical characterization studies designed to determine...

  8. 40 CFR 792.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 32 2014-07-01 2014-07-01 false Physical and chemical characterization... A Study § 792.135 Physical and chemical characterization studies. (a) All provisions of the GLPs shall apply to physical and chemical characterization studies designed to determine...

  9. 40 CFR 792.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Physical and chemical characterization... A Study § 792.135 Physical and chemical characterization studies. (a) All provisions of the GLPs shall apply to physical and chemical characterization studies designed to determine...

  10. 40 CFR 792.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 33 2013-07-01 2013-07-01 false Physical and chemical characterization... A Study § 792.135 Physical and chemical characterization studies. (a) All provisions of the GLPs shall apply to physical and chemical characterization studies designed to determine...

  11. 40 CFR 792.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Physical and chemical characterization... A Study § 792.135 Physical and chemical characterization studies. (a) All provisions of the GLPs shall apply to physical and chemical characterization studies designed to determine...

  12. Numerical study of secondary separation in glancing shock/turbulent boundary layer interactions

    NASA Astrophysics Data System (ADS)

    Panaras, Argyris G.; Stanewsky, Egon

    1992-07-01

    Experimentally it has been found that in moderate strength glancing shock/turbulent boundary layer interactions, as they occur, e.g., in supersonic and hypersonic intakes, a secondary separation line appears in the surface flow pattern. In the present paper, a flow of this type, studied at the Pennsylvania State University, is simulated numerically. It is shown that if the turbulence model of Baldwin and Lomax is applied according to the physics of the flow, the resulting solution agrees very well with the experimental evidence (wall pressure, skin friction, flow angle). Then, post-processing of the solution reveals that in this type of interaction the secondary separation phenomenon is similar to that observed in flows around bodies at high incidence. Furthermore, it has been found that the secondary separation adversely affects the conical nature of the flow. The dynamic characteristics of the conical vortex which are known to appear in these types of flow change in such a way that the various flow parameters exhibit a variation along conical rays in the region of the conical vortex, instead of remaining constant, a requirement for a purely conical flow.

  13. Defective germanene as a high-efficiency helium separation membrane: a first-principles study.

    PubMed

    Zhu, Lei; Chang, Xiao; He, Daliang; Xue, Qingzhong; Li, Xiaofang; Jin, Yakang; Zheng, Haixia; Ling, Cuicui

    2017-03-01

    Development of low energy cost membranes for separating helium from natural gas is highly desired. Using van der Waals-corrected first-principles density functional theory (DFT) calculations, we theoretically investigate the helium separation performance of divacancy-defective germanene. The 555 777 divacancy-defective germanene presents a 0.53 eV energy barrier for helium, which is slightly larger than the energy threshold value of gas molecule penetration of a membrane (0.5 eV). Thus, the 555 777 divacancy-defective germanene is difficult for helium to permeate, except under high temperature or pressure. However, the 585 divacancy-defective germanene presents a surmountable energy barrier (0.27 eV) for helium, and it shows extremely high helium selectivities relative to other studied gas molecules. Especially, the He/Ne selectivity can be as high as 1 × 10(4) at room temperature. Together with the acceptable permeance for helium, the 585 divacancy-defective germanene can be used for helium separation with remarkably good performance.

  14. Further theoretical studies of modified cyclone separator as a diesel soot particulate emission arrester.

    PubMed

    Mukhopadhyay, N; Bose, P K

    2009-10-01

    Soot particulate emission reduction from diesel engine is one of the most emerging problems associated with the exhaust pollution. Diesel particulate filters (DPF) hold out the prospects of substantially reducing regulated particulate emissions but the question of the reliable regeneration of filters still remains a difficult hurdle to overcome. Many of the solutions proposed to date suffer from design complexity, cost, regeneration problem and energy demands. This study presents a computer aided theoretical analysis for controlling diesel soot particulate emission by cyclone separator--a non contact type particulate removal system considering outer vortex flow, inner vortex flow and packed ceramic fiber filter at the end of vortex finder tube. Cyclone separator with low initial cost, simple construction produces low back pressure and reasonably high collection efficiencies with reduced regeneration problems. Cyclone separator is modified by placing a continuous ceramic packed fiber filter placed at the end of the vortex finder tube. In this work, the grade efficiency model of diesel soot particulate emission is proposed considering outer vortex, inner vortex and the continuous ceramic packed fiber filter. Pressure drop model is also proposed considering the effect of the ceramic fiber filter. Proposed model gives reasonably good collection efficiency with permissible pressure drop limit of diesel engine operation. Theoretical approach is predicted for calculating the cut size diameter considering the effect of Cunningham molecular slip correction factor. The result shows good agreements with existing cyclone and DPF flow characteristics.

  15. Defective germanene as a high-efficiency helium separation membrane: a first-principles study

    NASA Astrophysics Data System (ADS)

    Zhu, Lei; Chang, Xiao; He, Daliang; Xue, Qingzhong; Li, Xiaofang; Jin, Yakang; Zheng, Haixia; Ling, Cuicui

    2017-03-01

    Development of low energy cost membranes for separating helium from natural gas is highly desired. Using van der Waals-corrected first-principles density functional theory (DFT) calculations, we theoretically investigate the helium separation performance of divacancy-defective germanene. The 555 777 divacancy-defective germanene presents a 0.53 eV energy barrier for helium, which is slightly larger than the energy threshold value of gas molecule penetration of a membrane (0.5 eV). Thus, the 555 777 divacancy-defective germanene is difficult for helium to permeate, except under high temperature or pressure. However, the 585 divacancy-defective germanene presents a surmountable energy barrier (0.27 eV) for helium, and it shows extremely high helium selectivities relative to other studied gas molecules. Especially, the He/Ne selectivity can be as high as 1 × 104 at room temperature. Together with the acceptable permeance for helium, the 585 divacancy-defective germanene can be used for helium separation with remarkably good performance.

  16. Characterization on the phase separation behavior of styrene-butadiene rubber/polyisoprene/organoclay ternary blends under oscillatory shear

    NASA Astrophysics Data System (ADS)

    Liu, Xianggui; Dong, Xia; Liu, Wei; Xing, Qian; Zou, Fasheng; Han, Charles C.; Wang, Dujin; Liang, Aimin; Li, Chuanqing; Xie, Ximing

    2015-09-01

    The present work investigated the influence of organoclay (organo-montmorillonite, OMMT) on the phase separation behavior and morphology evolution of solution polymerized styrene-butadiene rubber (SSBR)/low vinyl content polyisoprene (LPI) blends with rheological methodology. It was found that the incorporation of OMMT not only reduced the droplet size of the dispersion phase, slowed down the phase separation kinetics, also enlarged the processing miscibility window of the blends. The determination on the wetting parameters indicated that due to the oscillatory shear effect, the OMMT sheets might localize at the interface between the two phases and act as compatibilizer or rigid barrier to prevent domain coarsening, resulting in slow phase separation kinetics, small droplet size, and stable morphology. The analysis of rheological data by the Palierne model provided further confirmation that the addition of OMMT can decrease the interfacial tension and restrict the relaxation of melt droplets. Therefore, a vivid "sea-fish-net" model was proposed to describe the effect of OMMT on the phase separation behavior of SSBR/LPI blends, in which the OMMT sheets acted as the barrier (net) to slow down the domain coarsening/coalescence in phase separation process of SSBR/LPI blends.

  17. Isolation and characterization of mesenchymal stem cells from the fat layer on the density gradient separated bone marrow.

    PubMed

    Insausti, Carmen L; Blanquer, Miguel Blanquer; Olmo, Luis Meseguer; López-Martínez, María C; Ruiz, Xavier Férez; Lozano, Francisco J Rodríguez; Perianes, Valentín Cabañas; Funes, Consuelo; Nicolás, Francisco J; Majado, María J; Jiménez, José M Moraleda

    2012-01-20

    The density gradient centrifugation method was originally designed for the isolation of mononuclear peripheral blood cells and rapidly adapted to fractionate bone marrow (BM) cells. This method involves the use of gradient density solutions with low viscosity and low osmotic pressure that allows erythrocytes and more mature cells gravitate to the bottom at a density fraction superior to 1.080 g/dL; mononuclear cells (MNCs) held in the plasma-solution to interphase at a density between 1.053 and 1.073 g/dL; plasma, dilution medium and anticoagulant to occupy a density less than 1.050 g/dL and the fat cells to float due to their very low density. BM-mesenchymal stem cells (MSCs) are usually obtained after the separation and cultures of BM-MNCs from the plasma-solution interphase, which is traditionally considered the only source of progenitor cells (hematopoietic and nonhematopoietic). In this study evidences that MSCs could be isolated from the very low-density cells of the fat layer are presented. In addition, we demonstrated that the MSCs obtained from these cells have similar immunophenotypic characteristics, and similar proliferative and differentiation potential to those obtained from the MNCs at plasma-solution interphase. The method represents a simple and cost effective way to increase the MSCs yield from each BM donor, without the need to look for other sources, additional manipulation of cells, and risks of contamination or disturbances of the potential of differentiation. These cells might serve as a complementary source of MSCs to facilitate preclinical and clinical application in tissue engineering and cell therapy.

  18. Separation and characterization of NOM by high-performance liquid chromatography and on-line three-dimensional excitation emission matrix fluorescence detection.

    PubMed

    Wu, F C; Evans, R D; Dillon, P J

    2003-08-15

    By using high-performance size exclusion chromatography (HPSEC) and reversed-phase high-performance liquid chromatography with on-line three-dimensional excitation emission matrix fluorescence detection, we measured fluorescence properties of natural organic matter (NOM) as a function of molecular size (MS) and polarity. The work was carried out with Suwannee River Fulvic Acid, Aldrich Humic Acid, and a naturally occurring river NOM sample. Significant differences in fluorescence maximum pattern were found as NOM was separated chromatographically based on MS and polarity. There existed a strong relationship between MS, fluorescence pattern, and polarity. Humic-, fulvic-, and protein-like fluorescence fractions had distinct hydrophilic/hydrophobic nature. The results suggest that HPSEC may be better for characterizing major fulvic-like fluorescence and smaller MS fractions but not those having humic- and protein-like fluorescence and larger MS, which may be strongly adsorbed onto the HPSEC column because of their hydrophobic nature. This study has significant implications for further understanding the nature of NOM and its complexation with trace metals.

  19. 40 CFR 160.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Physical and chemical characterization... and chemical characterization studies. (a) All provisions of the GLP standards shall apply to physical and chemical characterization studies designed to determine stability, solubility, octanol...

  20. 40 CFR 160.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Physical and chemical characterization... and chemical characterization studies. (a) All provisions of the GLP standards shall apply to physical and chemical characterization studies designed to determine stability, solubility, octanol...

  1. 40 CFR 160.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Physical and chemical characterization... and chemical characterization studies. (a) All provisions of the GLP standards shall apply to physical and chemical characterization studies designed to determine stability, solubility, octanol...

  2. 40 CFR 160.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Physical and chemical characterization... and chemical characterization studies. (a) All provisions of the GLP standards shall apply to physical and chemical characterization studies designed to determine stability, solubility, octanol...

  3. 40 CFR 160.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Physical and chemical characterization... and chemical characterization studies. (a) All provisions of the GLP standards shall apply to physical and chemical characterization studies designed to determine stability, solubility, octanol...

  4. Multi-instrument remote sensor characterization study

    SciTech Connect

    Riese, C.; Best, L.; McLaughlin, S.; Eaton, F.; Hines, J.; Peterman, R.

    1996-12-31

    During April 1995, the US Environmental Protection Agency, in cooperation with the National Oceanic and Atmospheric Administration, sponsored a Ground-Based Remote Sensor Characterization Study at the Boulder Atmospheric Observatory (BAO) near Erie, Colorado. The BAO is a 300-meter instrumented tower used as a ground-truth profile device for calibrating tower mounted in-situ or ground-based remote sensors. The following remote sensors were evaluated: 915 MHZ Boundary Layer Radar Profiler; Phased Array Sodar; Fixed-Beam Sodar; and 2.7 GHz FM-CW Backscatter Radar Profiler. This paper examines the excellent agreement among these various instruments and the BAO tower using traditional comparative graphic plots and tables. Data were collected at the BAO site continuously over a one-month period. The variety of synoptic weather features and diurnal inversion cycles during the month made the comparisons particularly useful for objective data comparison analyses. The relationship between the remote sensor data and current issues of air pollution meteorology such as tropospheric ozone management strategies is also examined.

  5. Reducing Societal Obesity: Establishing a Separate Exercise Model through Studies of Group Behavior

    PubMed Central

    Puterbaugh, J. S.

    2016-01-01

    The past 50 years has brought attention to high and increasing levels of human obesity in most of the industrialized world. The medical profession has noticed, has evaluated, and has developed models for studying, preventing, and reversing obesity. The current model prescribes activity in specific quantities such as days, minutes, heart rates, and footfalls. Although decreased levels of activity have come from changes revolving around built environments and social networks, the existing medical model to lower body weights by increasing activity remains individually prescriptive. It is not working. The study of societal obesity precludes the individual and must involve group behavioral studies. Such studies necessitate acquiring separate tools and, therefore, require a significant change in the evaluation and treatment of obesity. Finding groups with common activities and lower levels of obesity would allow the development of new models of land use and encourage active lifestyles through shared interests. PMID:27429800

  6. Characterizing the resolution and accuracy of a second-generation traveling-wave ion mobility separator for biomolecular ions.

    PubMed

    Zhong, Yueyang; Hyung, Suk-Joon; Ruotolo, Brandon T

    2011-09-07

    High-accuracy, high-resolution ion mobility measurements enable a vast array of important contemporary applications in biological chemistry. With the recent advent of both new, widely available commercial instrumentation and also new calibration datasets tailored for the aforementioned commercial instrumentation, the possibilities for extending such high performance measurements to a diverse set of applications have never been greater. Here, we assess the performance characteristics of a second-generation traveling-wave ion mobility separator, focusing on those figures of merit that lead to making measurements of collision cross-section having both high precision and high accuracy. Through performing a comprehensive survey of instrument parameters and settings, we find instrument conditions for optimized drift time resolution, cross-section resolution, and cross-section accuracy for a range of peptide, protein and multi-protein complex ions. Moreover, the conditions for high accuracy IM results are significantly different from those optimized for separation resolution, indicating that a balance between these two metrics must be attained for traveling wave IM separations of biomolecules. We also assess the effect of ion heating during IM separation on instrument performance.

  7. Synthesis and Photophysical Characterization of an Artificial Photosynthetic Reaction Center Exhibiting Acid-Responsive Regulation of Charge Separation

    NASA Astrophysics Data System (ADS)

    Pahk, Ian

    Non-photochemical quenching (NPQ) is a photoprotective regulatory mechanism essential to the robustness of the photosynthetic apparatus of green plants. Energy flow within the low-light adapted reaction centers is dynamically optimized to match the continuously fluctuating light conditions found in nature. Activated by compartmentalized decreases in pH resulting from photosynthetic activity during periods of elevated photon flux, NPQ induces rapid thermal dissipation of excess excitation energy that would otherwise overwhelm the apparatus's ability to consume it. Consequently, the frequency of charge separation decreases and the formation of potentially deleterious, high-energy intermediates slows, thereby reducing the threat of photodamage by disallowing their accumulation. Herein is described the synthesis and photophysical analysis of a molecular triad that mimics the effects of NPQ on charge separation within the photosynthetic reaction centers. Steady-state absorption and emission, time-resolved fluorescence, and transient absorption spectroscopies were used to demonstrate reversible quenching of the first singlet excited state affecting the quantum yield of charge separation by approximately one order of magnitude. As in the natural system, the populations of unquenched and quenched states and, therefore, the overall yields of charge separation were found to be dependent upon acid concentration.

  8. Electrical characterization of standard and radiation-hardened RCA CDP1856D 4-BIT, CMOS, bus buffer/separator

    NASA Technical Reports Server (NTRS)

    Stokes, R. L.

    1979-01-01

    Tests performed to determine accuracy and efficiency of bus separators used in microprocessors are presented. Functional, AC parametric, and DC parametric tests were performed in a Tektronix S-3260 automated test system. All the devices passed the functional tests and yielded nominal values in the parametric test.

  9. A multichannel gel electrophoresis and continuous fraction collection apparatus for high-throughput protein separation and characterization.

    PubMed

    Choi, Megan; Nordmeyer, Robert A; Cornell, Earl; Dong, Ming; Biggin, Mark D; Jin, Jian

    2010-01-01

    To facilitate a direct interface between protein separation by PAGE and protein identification by mass spectrometry, we developed a multichannel system that continuously collects fractions as protein bands migrate off the bottom of gel electrophoresis columns. The device was constructed using several short linear gel columns, each of a different percent acrylamide, to achieve a separation power similar to that of a long gradient gel. A "Counter Free-Flow" elution technique then allows continuous and simultaneous fraction collection from multiple channels at low cost. We demonstrate that rapid, high-resolution separation of a complex protein mixture can be achieved on this system using SDS-PAGE. In a 2.5 h electrophoresis run, for example, each sample was separated and eluted into 48-96 fractions over a mass range of approximately 10-150 kDa; sample recovery rates were 50% or higher; each channel was loaded with up to 0.3 mg of protein in 0.4 mL; and a purified band was eluted in two to three fractions (200 microL/fraction). Similar results were obtained when running native gel electrophoresis, but protein aggregation limited the loading capacity to about 50 microg per channel and reduced resolution.

  10. A multi-channel gel electrophoresis and continuous fraction collection apparatus for high throughput protein separation and characterization

    SciTech Connect

    Choi, Megan; Nordmeyer, Robert A.; Cornell, Earl; Dong, Ming; Biggin, Mark D.; Jin, Jian

    2009-10-02

    To facilitate a direct interface between protein separation by PAGE and protein identification by mass spectrometry, we developed a multichannel system that continuously collects fractions as protein bands migrate off the bottom of gel electrophoresis columns. The device was constructed using several short linear gel columns, each of a different percent acrylamide, to achieve a separation power similar to that of a long gradient gel. A Counter Free-Flow elution technique then allows continuous and simultaneous fraction collection from multiple channels at low cost. We demonstrate that rapid, high-resolution separation of a complex protein mixture can be achieved on this system using SDS-PAGE. In a 2.5 h electrophoresis run, for example, each sample was separated and eluted into 48-96 fractions over a mass range of 10-150 kDa; sample recovery rates were 50percent or higher; each channel was loaded with up to 0.3 mg of protein in 0.4 mL; and a purified band was eluted in two to three fractions (200 L/fraction). Similar results were obtained when running native gel electrophoresis, but protein aggregation limited the loading capacity to about 50 g per channel and reduced resolution.

  11. Glycoform Separation and Characterization of Cetuximab Variants by Middle-up Off-Line Capillary Zone Electrophoresis-UV/Electrospray Ionization-MS.

    PubMed

    Biacchi, Michael; Gahoual, Rabah; Said, Nassur; Beck, Alain; Leize-Wagner, Emmanuelle; François, Yannis-Nicolas

    2015-06-16

    Monoclonal antibodies (mAbs) are highly complex glycoproteins that present a wide range of microheterogeneities that requires multiple analytical methods for full structure assessment and quality control. Capillary zone electrophoresis-mass spectrometry (CZE-MS) couplings, especially by electrospray ionization (ESI), appear to be really attractive methods for the characterization of biological samples. However, due to the presence of non- or medium volatile salts in the background electrolyte (BGE), online CZE-ESI-MS coupling is difficult to implement for mAbs isoforms separation. Here, we report an original strategy to perform off-line CZE-ESI-MS using CZE-UV/fraction collection technology to perform CZE separation, followed by ESI-MS infusion of the different fractions using the capillary electrophoresis-electrospray ionization (CESI) interface as the nanoESI infusion platform. As the aim is to conserve electrophoretic resolution and complete compatibility with ESI-MS without sample treatment, hydroxypropylcellulose (HPC) coated capillary was used to prevent analyte adsorption and asymmetric CZE conditions involving different BGE at both ends of the capillary have been developed. The efficiency of our strategy was validated with the separation of Cetuximab charge variant by the middle-up approach. Molecular weights were measured for six charge variants detected in the CZE separation of Cetuximab subunits. The first three peaks correspond to Fc/2 variants with electrophoretic resolution up to 2.10, and the last three peaks correspond to F(ab')2 variants with average electrophoretic resolution of 1.05. Two Fc/2 C-terminal lysine variants were identified and separated. Moreover, separation of Fc/2 fragments allowed the glycoprofiling of the variants with the characterization of 7 different glycoforms. Regarding the F(ab')2 domain, 8 glycoforms were detected and separated in three different peaks following the presence of N-glycolyl neuraminic acid residues in some

  12. Experimental and Model Studies on Continuous Separation of 2-Phenylpropionic Acid Enantiomers by Enantioselective Liquid-Liquid Extraction in Centrifugal Contactor Separators.

    PubMed

    Feng, Xiaofeng; Tang, Kewen; Zhang, Pangliang; Yin, Shuangfeng

    2016-03-01

    Multistage enantioselective liquid-liquid extraction (ELLE) of 2-phenylpropionic acid (2-PPA) enantiomers using hydroxypropyl-β-cyclodextrin (HP-β-CD) as extractant was studied experimentally in a counter-current cascade of centrifugal contactor separators (CCSs). Performance of the process was evaluated by purity (enantiomeric excess, ee) and yield (Y). A multistage equilibrium model was established on the basis of single-stage model for chiral extraction of 2-PPA enantiomers and the law of mass conservation. A series of experiments on the extract phase/washing phase ratio (W/O ratio), extractant concentration, the pH value of aqueous phase, and the number of stages was conducted to verify the multistage equilibrium model. It was found that model predictions were in good agreement with the experimental results. The model was applied to predict and optimize the symmetrical separation of 2-PPA enantiomers. The optimal conditions for symmetric separation involves a W/O ratio of 0.6, pH of 2.5, and HP-β-CD concentration of 0.1 mol L(-1) at a temperature of 278 K, where eeeq (equal enantiomeric excess) can reach up to 37% and Yeq (equal yield) to 69%. By simulation and optimization, the minimum number of stages was evaluated at 98 and 106 for eeeq > 95% and eeeq > 97%.

  13. A Population Study of Wide-Separation Brown Dwarf Companions to Main Sequence Stars

    NASA Technical Reports Server (NTRS)

    Smith, Jeffrey J.

    2005-01-01

    Increased interest in infrared astronomy has opened the frontier to study cooler objects that shed significant light on the formation of planetary systems. Brown dwarf research provides a wealth of information useful for sorting through a myriad of proposed formation theories. Our study combines observational data from 2MASS with rigorous computer simulations to estimate the true population of long-range (greater than 1000 AU) brown dwarf companions in the solar neighborhood (less than 25 pc from Earth). Expanding on Gizis et al. (2001), we have found the margin of error in previous estimates to be significantly underestimated after we included orbit eccentricity, longitude of pericenter, angle of inclination, field star density, and primary and secondary luminosities as parameters influencing the companion systems in observational studies. We apply our simulation results to current L- and T-dwarf catalogs to provide updated estimates on the frequency of wide-separation brown dwarf companions to main sequence stars.

  14. Study on a novel process for the separation of phospholipids, triacylglycerol and cholesterol from egg yolk.

    PubMed

    Su, Yujie; Tian, Ying; Yan, Ruhui; Wang, Chenying; Niu, Fuge; Yang, Yanjun

    2015-07-01

    A novel process for effective separation of phospholipids, triacylglycerol and cholesterol from fresh egg yolk has been developed and validated in this study. Ethanol was the only organic solvent used in the whole procedure. Following initial separation of protein and total lipids by ethanol, most of solidified triacylglycerol was removed from total lipids by low temperature treatment of ethanol extracts within 10 h. Then, β-cyclodextrin (β-CD) was used to remove cholesterol from the remaining ethanol extracts and recycling of β-CD was also studied to obtain cholesterol and reusable β-CD powder. The highest cholesterol removal rate of nearly 99 % was obtained at β-CD: cholesterol molar ratio of 5:1, water addition of 15 g/g β-CD and reacting temperature of 50 °C. Ethanol in residual ethanol extracts was removed for obtaining phospholipids by rotary evaporation. The phospholipids produced in this procedure without cholesterol could be safety used as emulsifiers in food or cosmetic industry.

  15. Fundamental Characterization Studies of Advanced Photocatalytic Materials

    NASA Astrophysics Data System (ADS)

    Phivilay, Somphonh Peter

    Solar powered photocatalytic water splitting has been proposed as a method for the production of sustainable, non-carbon hydrogen fuel. Although much technological progress has been achieved in recent years in the discovery of advanced photocatalytic materials, the progress in the fundamental scientific understanding of such novel, complex mixed oxide and oxynitride photocatalysts has significantly lagged. One of the major reasons for this slow scientific progress is the limited number of reported surface characterization studies of the complex bulk mixed oxide and oxynitride photocatalyst systems. Although photocatalytic splitting of water by bulk mixed oxide and oxynitride materials involves both bulk (generation of excited electrons and holes) and surface phenomena (reaction of H2O with excited electrons and holes at the surface), the photocatalysis community has almost completely ignored the surface characteristics of such complex bulk photocatalysts and correlates the photocatalytic properties with bulk properties. Some of the most promising photocatalyst systems (NaTaO3, GaN, (Ga1-xZnx)(N1-xOx) and TaON) were investigated to establish fundamental bulk/surface structure photoactivity relationships. The bulk molecular and electronic structures of the photocatalysts were determined with Raman and UV-vis spectroscopy. Photoluminescence (PL) and transient PL spectroscopy were provided insight into how recombination of photogenerated electrons is related to the photocatalysis activity. The chemical states and atomic compositions of the surface region of the photocatalysts were determined with high resolution X-ray photoelectron spectroscopy (˜1-3 nm) and high sensitivity-low energy ion scattering spectroscopy (˜0.3 nm). The new insights obtained from surface characterization clarified the role of La and Ni promoters species for the NaTaO3 photocatalyst system. The La2O3 additive was found to be a structural promoter that stabilizes small NaTaO3 nanoparticles (NPs

  16. Numerical study of lift augmentation in massively separated turbulent flows with forcing

    NASA Astrophysics Data System (ADS)

    Denny, Andrew Gregory

    At high angles of attack the flow over any lifting body experiences massive separation. The resulting shear layers naturally tend to roll up into large vortical structures. The presence and motion of these structures has a significant impact on the continuing flowfield development. By applying an artificial forcing to the shedding shear layer the rollup can be intensified or reduced, and the entire vorticity field may be altered. Control of these vortical structures by forcing to enhance lift has been the goal of numerous investigations, and some progress has been made in understanding how an unsteady forcing can be used to advantage. This study describes work done in determining the effectiveness of using computational simulations to model massively separated, turbulent unsteady flowfields subject to small-amplitude mechanical forcing. Algorithm development and validation highlight certain concerns that arise in the modeling of such unsteady flowfields using the Reynolds-Averaged Navier-Stokes equations, and questions of grid density, numerical diffusion, timestep size, and turbulence modeling are addressed with a suite of sample calculations. Simulation of flowfields undergoing mechanical forcing by flap is accomplished using an overset grid methodology with the flow solver. Excellent agreement is demonstrated for flow over a NACA 63sb3-018 airfoil with a small flap placed near the leading edge separation point. Computed values of the unforced lift and drag coefficients agree with given experimental values to less than 2%. Forcing frequencies for the experimental configuration were in the range of global shedding frequency, and the maximum variation of the aerodynamic coefficients was seen when the forcing frequency was equal to the shedding frequency. Excellent agreement with experiment is also found for the cases involving forcing, and the data is used to explain the effect of forcing in terms of a global receptivity mechanism.

  17. Map Separates

    USGS Publications Warehouse

    ,

    2001-01-01

    U.S. Geological Survey (USGS) topographic maps are printed using up to six colors (black, blue, green, red, brown, and purple). To prepare your own maps or artwork based on maps, you can order separate black-and-white film positives or negatives for any color printed on a USGS topographic map, or for one or more of the groups of related features printed in the same color on the map (such as drainage and drainage names from the blue plate.) In this document, examples are shown with appropriate ink color to illustrate the various separates. When purchased, separates are black-and-white film negatives or positives. After you receive a film separate or composite from the USGS, you can crop, enlarge or reduce, and edit to add or remove details to suit your special needs. For example, you can adapt the separates for making regional and local planning maps or for doing many kinds of studies or promotions by using the features you select and then printing them in colors of your choice.

  18. Hybrid Enrichment Verification Array: Module Characterization Studies

    SciTech Connect

    Zalavadia, Mital A.; Smith, Leon E.; McDonald, Benjamin S.; Kulisek, Jonathan A.; Mace, Emily K.; Deshmukh, Nikhil S.

    2016-03-01

    The work presented in this report is focused on the characterization and refinement of the Hybrid Enrichment Verification Array (HEVA) approach, which combines the traditional 186-keV 235U signature with high-energy prompt gamma rays from neutron capture in the detector and surrounding collimator material, to determine the relative enrichment and 235U mass of the cylinder. The design of the HEVA modules (hardware and software) deployed in the current field trial builds on over seven years of study and evolution by PNNL, and consists of a ø3''×3'' NaI(Tl) scintillator coupled to an Osprey digital multi-channel analyzer tube base from Canberra. The core of the HEVA methodology, the high-energy prompt gamma-ray signature, serves as an indirect method for the measurement of total neutron emission from the cylinder. A method for measuring the intrinsic efficiency of this “non-traditional” neutron signature and the results from a benchmark experiment are presented. Also discussed are potential perturbing effects on the non-traditional signature, including short-lived activation of materials in the HEVA module. Modeling and empirical results are presented to demonstrate that such effects are expected to be negligible for the envisioned implementation scenario. In comparison to previous versions, the new design boosts the high-energy prompt gamma-ray signature, provides more flexible and effective collimation, and improves count-rate management via commercially available pulse-processing electronics with a special modification prompted by PNNL.

  19. Branched polymers characterized by comprehensive two-dimensional separations with fully orthogonal mechanisms: molecular-topology fractionation×size-exclusion chromatography.

    PubMed

    Edam, Rob; Mes, Edwin P C; Meunier, David M; Van Damme, Freddy A; Schoenmakers, Peter J

    2014-10-31

    Polymer separations under non-conventional conditions have been explored to obtain a separation of long-chain branched polymers from linear polymers with identical hydrodynamic size. In separation media with flow-through channels of the same order as the size of the analyte molecules in solution, the separation and the elution order of polymers are strongly affected by the flow rate. At low flow rates, the largest polymers are eluted last. At high flow rates, they are eluted first. By tuning the channel size and flow rate, conditions can be found where separation becomes independent of molar mass or size of linear polymers. Long-chain branched polymers did experience lower migration rates under these conditions and can be separated from linear polymers. This type of separation is referred to as molecular-topology fractionation (MTF) at critical conditions. Separation by comprehensive two-dimensional molecular-topology fractionation and size-exclusion chromatography (MTF×SEC) was used to study the retention characteristics of MTF. Branching selectivity was demonstrated for three- and four-arm "star" polystyrenes of 3-5×10(6)g/mol molar mass. Baseline separation could be obtained between linear polymer, Y-shaped molecules, and X-shaped molecules in a single experiment at constant flow rate. For randomly branched polymers, the branching selectivity inevitably results in an envelope of peaks, because it is not possible to fully resolve the huge numbers of different branched and linear polymers of varying molar mass. It was concluded that MTF involves partial deformation of polymer coils in solution. The increased coil density and resistance to deformation can explain the different retention behavior of branched molecules.

  20. In situ nanomanipulators as a tool to separate individual tobermorite crystals for AFM studies.

    PubMed

    Yang, Tianhe; Holzer, Lorenz; Kägi, Ralf; Winnefeld, Frank; Keller, Bruno

    2007-10-01

    Atomic force microscopy (AFM) studies of cementitious materials are limited, mainly due to the lack of appropriate sample preparation techniques. In porous autoclaved aerated concrete (AAC), calcium silicate hydrate (C-S-H) is produced in its crystalline form, tobermorite. The crystals are lath-like with a length of several micrometers. In this work, we demonstrate the application of nanomanipulators to separate an individual tobermorite crystal from the bulk AAC for subsequent AFM investigations. The nanomanipulators are operated directly in an environmental scanning electron microscope (ESEM). We studied the interaction between moisture and the tobermorite surface under controlled relative humidity (RH). The results of topography and adhesion force measurements with AFM suggest that the surface of tobermorite is hydrophobic, which contrasts the macroscopic material properties (e.g. moisture transport in capillary pores).

  1. Transient absorption studies of the primary charge separation in photosystem II

    SciTech Connect

    Donovan, B.; Walker, L.A. II; Yocum, C.F.; Sension, R.J.

    1996-02-01

    Femtosecond transient absorption studies of the primary charge separation in photosystem II (PSII) are presented. A careful study of the dependence of the observed signal on laser intensity demonstrates that the multiple excitation of reaction centers produces additional fast components not observed at low excitation energy. In the regime where the observed signals are linear with excitation energy, a 20 {+-} 2 ps rise of the pheophytin anion absorption, bleach of the pheophytin Q{sub {chi}} absorption, and appearance of the chlorophyll cation absorption are observed. Three different protocols, involving varying exposure of the PSII complex to the detergent Triton X-100, are used to prepare D1-D2-cyt b{sub 559} complexes from spinach. The kinetic signals are independent of the method of sample preparation. 35 refs., 5 figs.

  2. Separation and sampling of ice nucleation chamber generated ice particles by means of the counterflow virtual impactor technique for the characterization of ambient ice nuclei.

    NASA Astrophysics Data System (ADS)

    Schenk, Ludwig; Mertes, Stephan; Kästner, Udo; Schmidt, Susan; Schneider, Johannes; Frank, Fabian; Nillius, Björn; Worringen, Annette; Kandler, Konrad; Ebert, Martin; Stratmann, Frank

    2014-05-01

    In 2011, the German research foundation (DFG) research group called Ice Nuclei Research Unit (INUIT (FOR 1525, project STR 453/7-1) was established with the objective to achieve a better understanding concerning heterogeneous ice formation. The presented work is part of INUIT and aims for a better microphysical and chemical characterization of atmospheric aerosol particles that have the potential to act as ice nuclei (IN). For this purpose a counterflow virtual impactor (Kulkarni et al., 2011) system (IN-PCVI) was developed and characterized in order to separate and collect ice particles generated in the Fast Ice Nucleus Chamber (FINCH; Bundke et al., 2008) and to release their IN for further analysis. Here the IN-PCVI was used for the inertial separation of the IN counter produced ice particles from smaller drops and interstitial particles. This is realized by a counterflow that matches the FINCH output flow inside the IN-PCVI. The choice of these flows determines the aerodynamic cut-off diameter. The collected ice particles are transferred into the IN-PCVI sample flow where they are completely evaporated in a particle-free and dry carrier air. In this way, the aerosol particles detected as IN by the IN counter can be extracted and distributed to several particle sensors. This coupled setup FINCH, IN-PCVI and aerosol instrumentation was deployed during the INUIT-JFJ joint measurement field campaign at the research station Jungfraujoch (3580m asl). Downstream of the IN-PCVI, the Aircraft-based Laser Ablation Aerosol Mass Spectrometer (ALABAMA; Brands et al., 2011) was attached for the chemical analysis of the atmospheric IN. Also, number concentration and size distribution of IN were measured online (TROPOS) and IN impactor samples for electron microscopy (TU Darmstadt) were taken. Therefore the IN-PCVI was operated with different flow settings than known from literature (Kulkarni et al., 2011), which required a further characterisation of its cut

  3. Compressible DNS study of separation bubbles for flow past a low pressure turbine blade

    NASA Astrophysics Data System (ADS)

    Ranjan, Rajesh; Deshpande, Suresh; Narasimha, Roddam

    2014-11-01

    A representative low pressure turbine blade T106A is subjected to a direct numerical simulation (DNS) study for low Reynolds Number (Re = 51831 based on inflow velocity and axial chord) and angle of incidence (45.5 deg from the axial chord). The DNS code used here solves the compressible Navier-Stokes equations and uses a semi-kinetic energy preserving scheme. A hybrid grid is used for the computational domain, with a very fine wall-bounded boundary layer grid near the surface of the blade and an unstructured grid for rest of the domain. Total grid size for the current simulation is around 160 million. In the mean flow, a long but shallow separation bubble is found near the trailing edge. However, the instantaneous flow reveals a train of bubbles at this location. These instantaneous bubbles continually break and merge in time. The presence of these separation bubbles make the flow very complicated, as the bubbles are responsible for tripping the otherwise laminar flow to a transitional state. Skin friction and heat transfer co-efficient are also computed over the blade to understand the effect of these bubbles on parameters of engineering importance. Supported by a GATET funded project on DNS of turbomachinery blading. The Param Yuva-II at CDAC was utilized for the simulations.

  4. Simulation of π0-γ separation study for proposed CMS forward electromagnetic calorimeter

    DOE PAGES

    Roy, Ashim; Jain, Shilpi; Banerjee, Sunanda; ...

    2016-11-11

    The Forward Electromagnetic Calorimeter of the CMS detector is going to be upgraded in the high luminosity running as the energy of the present Electromagnetic Calorimeter (PbWO4) will degrade in the high luminosity (luminosity 1034 cm-2 s-1) running due to extensive radiation (hadron flux 1013 neutrons cm,-2). Shashlik Electromagnetic Calorimeter which consists of alternate layers of 1.5 mm LYSO(Ce) crystal plates and 2.5 mm Tungsten absorbers, was a proposal for high luminosity running. One of the performance points for any electromagnetic calorimeter is the ability to separate π0 s from true photons, since final states with photons are a cleanmore » and one of the most important final states in proton-proton collisions at the LHC. As a result, the objective of this project is to study the possibility of π0 and γ separation in the Shashlik detector using Multivariate Analysis (MVA) technique.« less

  5. Numerical study of three-dimensional separation and flow control at a wing/body junction

    NASA Technical Reports Server (NTRS)

    Ash, Robert L.; Lakshmanan, Balakrishnan

    1989-01-01

    The problem of three-dimensional separation and flow control at a wing/body junction has been investigated numerically using a three-dimensional Navier-Stokes code. The numerical code employs an algebraic grid generation technique for generating the grid for unmodified junction and an elliptic grid generation technique for filleted fin junction. The results for laminar flow past a blunt fin/flat plate junction demonstrate that after grid refinement, the computations agree with experiment and reveal a strong dependency of the number of vortices at the junction on Mach number and Reynolds number. The numerical results for pressure distribution, particle paths and limiting streamlines for turbulent flow past a swept fin show a decrease in the peak pressure and in the extent of the separated flow region compared to the laminar case. The results for a filleted juncture indicate that the streamline patterns lose much of their vortical character with proper filleting. Fillets with a radius of three and one-half times the fin leading edge diameter or two times the incoming boundary layer thickness, significantly weaken the usual necklace interaction vortex for the Mach number and Reynolds number considered in the present study.

  6. Separation of chiral nanotubes with an opposite handedness by chiral oligopeptide adsorption: A molecular dynamics study.

    PubMed

    Raffaini, Giuseppina; Ganazzoli, Fabio

    2015-12-18

    The separation of enantiomeric chiral nanotubes that can form non-covalent complexes with an unlike stability upon adsorption of chiral molecules is a process of potential interest in different fields and applications. Using fully atomistic molecular dynamics simulations, we report in this paper a theoretical study of the adsorption and denaturation of an oligopeptide formed by 16 chiral amino acids having a helical structure in the native state on both the inner and the outer surface of the chiral (10, 20) and (20, 10) single-walled carbon nanotubes having an opposite handedness, and of the armchair (16, 16) nanotube with a similar diameter for comparison. In the final adsorbed state, the oligopeptide loses in all cases its native helical conformation, assuming elongated geometries that maximize its contact with the surface through all the 16 amino acids. We find that the complexes formed by the two chiral nanotubes and the chosen oligopeptide have a strongly unlike stability both when adsorption takes place on the outer convex surface of the nanotube, and when it occurs on the inner concave surface. Thus, our molecular simulations indicate that separation of chiral, enantiomeric carbon nanotubes for instance by chromatographic methods can indeed be carried out using oligopeptides of a sufficient length.

  7. Kinetics study of phase separation in polyacrylic acid/nematic LC system by optical technique

    NASA Astrophysics Data System (ADS)

    Mucha, Maria; Krolikowski, Z.

    2002-06-01

    Thin polymer layers containing liquid crystal LC of non- linear optical properties were obtained from polyacrylic acid. Samples were produced by phase separation as a consequence of chemical polymerization (PIPS method) resulting in precipitation of liquid crystals in the form of droplets in a polymer matrix being formed. Films were produced in variable conditions of polymerization time and temperature and different content of an initiator (1 - 3 wt%). They contained of 10 - 40 wt% of LC. The cell thickness was constant and equal to 20 micrometers . Systems obtained in this way were subjected to thermo-optical and electro-optical studies, morphological structure investigation and DSC analysis. The polymerization time has a significant influence on the size and number of LC droplets. The presence of benzoyl peroxide can cause partial destruction of LC properties which is reflected by a decrease of isotropization temperature TI of the liquid crystal. An increase of the initiator amount shortens the time of polymerization (ti), while process enthalpy ((Delta) H) increases. Hence, the liquid crystal separation time decreases as well. Films prepared by this method present good electro-optical properties. Rise and decay times of orientation are short and equal to 2 - 17 ms (depending on driving voltage applied) and about 80 ms, respectively. Threshold voltage for the best sample is equal to 5 V. Optimal conditions are found: LC content equals 20%, wt(i) equals 1%, polymerization temperature Tp equals 100 - 110 degree(s)C.

  8. Development of a perfusion ion-exchange chromatography method for the separation of soybean proteins and its application to cultivar characterization.

    PubMed

    Heras, J M; Marina, M L; García, M C

    2007-06-15

    A perfusion ion-exchange chromatography method has been designed, for the first time, for the separation of soybean proteins and its application to the characterization of soybean cultivars. For that purpose, the gradient, the mobile phase composition (buffer concentration, buffer pH, and elution salt), and the temperature were optimized. The method consisted of a two-step gradient (0% B for 2 min and from 0 to 50% B in 10 min) being mobile phase A a 2 0mM borate buffer (pH 9) and mobile phase B a 20 mM borate buffer (pH 9) containing 1M sodium chloride. The procedure used for the preparation of sample solutions was significantly simpler than that proposed by other authors and basically consisted of dissolving in water. This method enabled the separation of soybean proteins from a soybean protein isolate in 11 peaks in about 9 min. The method was used to separate soybean proteins in different commercial soybeans. In general, the 11 peaks yielded by the soybean protein isolate were also observed in the chromatograms of all soybeans. However, the area percentages of every peak in every soybean enabled the differentiation between soybeans. Moreover, the method was also used to separate soybean proteins in the proteic fractions obtained from every soybean. Multivariate methods were used for patterns recognition and the classification of samples.

  9. Key parameters for behaviour related to source separation of household organic waste: A case study in Hanoi, Vietnam.

    PubMed

    Kawai, Kosuke; Huong, Luong Thi Mai

    2017-03-01

    Proper management of food waste, a major component of municipal solid waste (MSW), is needed, especially in developing Asian countries where most MSW is disposed of in landfill sites without any pretreatment. Source separation can contribute to solving problems derived from the disposal of food waste. An organic waste source separation and collection programme has been operated in model areas in Hanoi, Vietnam, since 2007. This study proposed three key parameters (participation rate, proper separation rate and proper discharge rate) for behaviour related to source separation of household organic waste, and monitored the progress of the programme based on the physical composition of household waste sampled from 558 households in model programme areas of Hanoi. The results showed that 13.8% of 558 households separated organic waste, and 33.0% discharged mixed (unseparated) waste improperly. About 41.5% (by weight) of the waste collected as organic waste was contaminated by inorganic waste, and one-third of the waste disposed of as organic waste by separators was inorganic waste. We proposed six hypothetical future household behaviour scenarios to help local officials identify a final or midterm goal for the programme. We also suggested that the city government take further actions to increase the number of people participating in separating organic waste, improve the accuracy of separation and prevent non-separators from discharging mixed waste improperly.

  10. Design, synthesis, characterization and study of novel conjugated polymers

    SciTech Connect

    Chen, Wu

    1997-06-24

    After introducing the subject of conjugated polymers, the thesis has three sections each containing a literature survey, results and discussion, conclusions, and experimental methods on the following: synthesis, characterization of electroluminescent polymers containing conjugated aryl, olefinic, thiophene and acetylenic units and their studies for use in light-emitting diodes; synthesis, characterization and study of conjugated polymers containing silole unit in the main chain; and synthesis, characterization and study of silicon-bridged and butadiene-linked polythiophenes.

  11. Neurophysiological Characterization of Subacute Stroke Patients: A Longitudinal Study

    PubMed Central

    Lamola, Giuseppe; Fanciullacci, Chiara; Sgherri, Giada; Bertolucci, Federica; Panarese, Alessandro; Micera, Silvestro; Rossi, Bruno; Chisari, Carmelo

    2016-01-01

    Various degrees of neural reorganization may occur in affected and unaffected hemispheres in the early phase after stroke and several months later. Recent literature suggests to apply a stratification based on lesion location and to consider patients with cortico-subcortical and subcortical strokes separately: different lesion location may also influence therapeutic response. In this study we used a longitudinal approach to perform TMS assessment (Motor Evoked Potentials, MEP, and Silent Period, SP) and clinical evaluations (Barthel Index, Fugl-Meyer Assessment for upper limb motor function and Wolf Motor Function Test) in 10 cortical-subcortical and 10 subcortical ischemic stroke patients. Evaluations were performed in a window between 10 and 45 days (t0) and at 3 months after the acute event (t1). Our main finding is that 3 months after the acute event patients affected by subcortical stroke presented a reduction in contralateral SP duration in the unaffected hemisphere; this trend is related to clinical improvement of upper limb motor function. In conclusion, SP proved to be a valid parameter to characterize cortical reorganization patterns in stroke survivors and provided useful information about motor recovery within 3 months in subcortical patients. PMID:27899888

  12. Parental separation in childhood, social capital, and suicide thoughts and suicide attempts: A population-based study.

    PubMed

    Lindström, Martin; Rosvall, Maria

    2015-09-30

    Studies of the association between parental separation in childhood and suicide thoughts and attempts are scarce. The aim of this study is to investigate associations between parental separation/divorce during childhood, and ever having had suicide thoughts and ever having made suicide attempt, adjusting for social capital and other covariates. In 2012 a cross-sectional public health survey was conducted in Scania, southern Sweden, with a postal questionnaire with 28,029 participants aged 18-80. Associations between parental separation/divorce during childhood and ever having considered suicide or having made suicide attempt were analysed by logistic regression. Overall, 12.1% of the men and 15.5% of the women had experienced suicide thoughts, and 3.2% of the men and 5.3% of the women had ever tried committing suicide. Among men, 20.4% had experienced parental separation during childhood until age 18, and among women 22.3%. Parental separation/divorce in childhood was with few exceptions significantly associated with ever having had suicide thoughts with the highest odds ratios for those who had experienced parental separation during ages 0-4 years. Parental separation/divorce in childhood was significantly associated with suicide attempts among men who had experienced parental separation/divorce at ages 0-4 and 15-18, and among women at any age 0-18.

  13. Particle size effects in particle-particle triboelectric charging studied with an integrated fluidized bed and electrostatic separator system

    NASA Astrophysics Data System (ADS)

    Bilici, Mihai A.; Toth, Joseph R.; Sankaran, R. Mohan; Lacks, Daniel J.

    2014-10-01

    Fundamental studies of triboelectric charging of granular materials via particle-particle contact are challenging to control and interpret because of foreign material surfaces that are difficult to avoid during contacting and measurement. The measurement of particle charge itself can also induce charging, altering results. Here, we introduce a completely integrated fluidized bed and electrostatic separator system that charges particles solely by interparticle interactions and characterizes their charge on line. Particles are contacted in a free-surface fluidized bed (no reactor walls) with a well-controlled fountain-like flow to regulate particle-particle contact. The charged particles in the fountain are transferred by a pulsed jet of air to the top of a vertically-oriented electrostatic separator consisting of two electrodes at oppositely biased high voltage. The free-falling particles migrate towards the electrodes of opposite charge and are collected by an array of cups where their charge and size can be determined. We carried out experiments on a bidisperse size mixture of soda lime glass particles with systematically varying ratios of concentration. Results show that larger particles fall close to the negative electrode and smaller particles fall close to the positive electrode, consistent with theory and prior experiments that larger particles charge positively and smaller particles charge negatively. The segregation of particles by charge for one of the size components is strongest when its collisions are mostly with particles of the other size component; thus, small particles segregate most strongly to the negative sample when their concentration in the mixture is small (and analogous results occur for the large particles). Furthermore, we find additional size segregation due to granular flow, whereby the fountain becomes enriched in larger particles as the smaller particles are preferentially expelled from the fountain.

  14. Particle size effects in particle-particle triboelectric charging studied with an integrated fluidized bed and electrostatic separator system

    SciTech Connect

    Bilici, Mihai A.; Toth, Joseph R.; Sankaran, R. Mohan; Lacks, Daniel J.

    2014-10-15

    Fundamental studies of triboelectric charging of granular materials via particle-particle contact are challenging to control and interpret because of foreign material surfaces that are difficult to avoid during contacting and measurement. The measurement of particle charge itself can also induce charging, altering results. Here, we introduce a completely integrated fluidized bed and electrostatic separator system that charges particles solely by interparticle interactions and characterizes their charge on line. Particles are contacted in a free-surface fluidized bed (no reactor walls) with a well-controlled fountain-like flow to regulate particle-particle contact. The charged particles in the fountain are transferred by a pulsed jet of air to the top of a vertically-oriented electrostatic separator consisting of two electrodes at oppositely biased high voltage. The free-falling particles migrate towards the electrodes of opposite charge and are collected by an array of cups where their charge and size can be determined. We carried out experiments on a bidisperse size mixture of soda lime glass particles with systematically varying ratios of concentration. Results show that larger particles fall close to the negative electrode and smaller particles fall close to the positive electrode, consistent with theory and prior experiments that larger particles charge positively and smaller particles charge negatively. The segregation of particles by charge for one of the size components is strongest when its collisions are mostly with particles of the other size component; thus, small particles segregate most strongly to the negative sample when their concentration in the mixture is small (and analogous results occur for the large particles). Furthermore, we find additional size segregation due to granular flow, whereby the fountain becomes enriched in larger particles as the smaller particles are preferentially expelled from the fountain.

  15. Multidisciplinary study of phase separation in a supersaturated Ni-Si alloy

    SciTech Connect

    Chen, Haydn . Dept. of Materials Science and Engineering); Epperson, J.E. )

    1990-07-01

    The subject of {gamma}{prime} precipitation in a Ni-12.5 at. % Si alloy has been studied by modern diffraction and scattering techniques in the small-angle and large angle regimes, and by transmission electron microscopy. Special attention is placed upon the mechanism and kinetic evolution of {gamma}{prime} precipitates as a function of ageing conditions. Methods are shown for the determination of interdiffusion coefficient, the interfacial energy and the coherent solubility. The strain effect, due to lattice mismatch, on the spatial correlation and preferred alignment of precipitates is addressed. Scaling law for the particle growth has been tested against the current theories. Results obtained from the three mutually beneficial techniques are shown to be consistent, thereby allowing an integral view of the phase separation process in this system. 29 refs., 19 figs., 3 tabs.

  16. FY 1995 separation studies for liquid low-level waste treatment at Oak Ridge National Laboratory

    SciTech Connect

    Bostick, D.T.; Arnold, W.D.; Burgess, M.W.

    1995-01-01

    During FY 1995, studies were continued to develop improved methods for centralized treatment of liquid low-level waste (LLLW) at Oak Ridge National Laboratory (ORNL). Focus in this reporting period was on (1) identifying the parameters that affect the selective removal of {sup 90}Sr and {sup 137}Cs, two of the principal radioactive contaminants expected in the waste; (2) validating the effectiveness of the treatment methods by testing an ac Melton Valley Storage Tank (MVST) supernate; (3) evaluating the optimum solid/liquid separation techniques for the waste; (4) identifying potential treatment methods for removal of technetium from LLLW; and (5) identifying potential methods for stabilizing the high-activity secondary solid wastes generated by the treatment.

  17. Separation and partial characterization of smooth muscle contractile material in the venom of the scorpion Heterometrus bengalensis.

    PubMed

    Kar, P K; Sarangi, B; Datta, A; Gomes, A; Lahiri, S C

    1983-01-01

    A smooth muscle contractile material was separated from crude venom of the scorpion Heterometrus bengalensis (found in Eastern India) by solvent extraction, gel filtration and thin layer chromatography. Smooth muscle contractile material could be extracted, in descending order of efficiency, with methanol, butanol, ethanol and acetone. The contractile material separated by gel filtration (Sephadex G-25) when further extracted, using the Folch procedure, showed a single spot in thin layer chromatography with one solvent system. Rechromatography of an eluate from this spot with another solvent system resolved it into three spots (SL1, SL2 and SL3, the mixture being designated as Substance L) which could be visualized either with iodine vapour, ninhydrin or molybdenum reagent. Eluates from the three spots contracted guinea-pig ileum which had been pretreated with antagonists of ACh, histamine, 5-HT and prostaglandins. Substance L and its fractions (SL1, SL2 and SL3) contain inorganic phosphorus, amino nitrogen and amino sugar, which point to the likelihood of their being glycophosphatides.

  18. Splitter imperfections in annular split-flow thin separation channels: experimental study of nonspecific crossover.

    PubMed

    Williams, P Stephen; Decker, Keith; Nakamura, Masayuki; Chalmers, Jeffrey J; Moore, Lee R; Zborowski, Maciej

    2003-12-01

    The separation performance of a split-flow thin (SPLITT) separation device depends on uniformity of channel thickness and the precise placement of the flow splitters at fixed distances between the channel walls. The observation of nonspecific crossover, that is, the transport of sample materials across the channel thickness without the influence of an applied field, has routinely been taken to indicate the presence of irregularities in splitter shape or placement. Computational fluid dynamics software may be used to predict the influence of splitter imperfections on nonspecific crossover, where it is assumed that sample transport is by convection alone. A previous study has shown how small inlet splitter imperfections can account for the relatively low levels of nonspecific crossover observed with typical annular SPLITT devices. This study, however, could not distinguish between the possible sources of nonspecific crossover; hydrodynamic lift or shear-induced diffusion could have contributed. To confirm the validity of the computational approach, a series of experiments has been carried out on a channel having a deliberately and severely bent splitter. Nonspecific crossover was measured for a range of inlet and outlet flow rate ratios, with the bent splitter placed at both the channel inlet and outlet. The severity of the splitter distortion was sufficient to produce significant nonspecific crossover over a wide range of flow conditions. Good agreement was found between experiment and prediction based on computational fluid dynamics, with experiment generally showing only slightly higher crossover than prediction. The quantitative agreement for this extreme case suggests that the contribution to nonspecific crossover due to geometrical imperfections can be well described using computational fluid dynamics.

  19. Study of the Application of Separation Control by Unsteady Excitation to Civil Transport Aircraft

    NASA Technical Reports Server (NTRS)

    McLean, J. D.; Crouch, J. D.; Stoner, R. C.; Sakurai, S.; Seidel, G. E.; Feifel, W. M.; Rush, H. M.

    1999-01-01

    This study provides a preliminary assessment of the potential benefits of applying unsteady separation control to transport aircraft. Estimates are given for some of the costs associated with a specific application to high-lift systems. High-leverage areas for future research were identified during the course of the study. The study was conducted in three phases. Phase 1 consisted of a coarse screening of potential applications within the aerodynamics discipline. Potential benefits were identified and in some cases quantified in a preliminary way. Phase 2 concentrated on the application to the wing high-lift system, deemed to have the greatest potential benefit for commercial transports. A team of experts, including other disciplines (i.e. hydraulic, mechanical, and electrical systems, structures, configurations, manufacturing, and finance), assessed the feasibility, benefits, and costs to arrive at estimates of net benefits. In both phases of the study, areas of concern and areas for future research were identified. In phase 3 of this study, the high-leverage areas for future research were prioritized as a guide for future efforts aimed at the application of active flow control to commercial transport aircraft.

  20. Initial study of dry ultrafine coal beneficiation utilizing triboelectric charging with subsequent electrostatic separation

    SciTech Connect

    Link, T.A.; Killmeyer, R.P.; Elstrodt, R.H.; Haden, N.H.

    1990-10-01

    A novel, dry process using electrostatics to beneficiate ultrafine coal is being developed by the Coal Preparation Division at the Pittsburgh Energy Technology Center. The historical concept of triboelectricity and its eventual use as a means of charging coal for electrostatic separation will be discussed. Test data from a first-generation and a second-generation Tribo-Electrostatic separator are presented showing the effects of feed particle size, separator voltage, solids concentration in air, and particle velocity on separation performance. 10 refs., 10 figs., 9 tabs.

  1. Separation and characterization of phenolic compounds and triterpenoid saponins in licorice (Glycyrrhiza uralensis) using mobile phase-dependent reversed-phase×reversed-phase comprehensive two-dimensional liquid chromatography coupled with mass spectrometry.

    PubMed

    Qiao, Xue; Song, Wei; Ji, Shuai; Wang, Qi; Guo, De-an; Ye, Min

    2015-07-10

    Licorice is one of the most popular herbal medicines worldwide. It contains a big array of phenolic compounds (flavonoids, coumarins, and diphenylethanones). Due to high structural diversity, low abundance, and co-elution with licorice saponins, these phenolic compounds are difficult to be separated by conventional chromatography. In this study, a mobile phase-dependent reversed-phase×reversed phase comprehensive two-dimensional liquid chromatography (RP×RP 2DLC) method was established to separate phenolic compounds in licorice (the roots of Glycyrrhiza uralensis). Organic solvents in the mobile phase were optimized to improve orthogonality of the first and second dimensions, and a synchronized gradient mode was used to improve chromatographic resolution. Finally, licorice extracts were eluted with methanol/water/formic acid in the first dimension (Acquity CSH C18 column), and acetonitrile/water/formic acid in the second dimension (Poroshell Phenyl-Hexyl column). By using this 2DLC system, a total of 311 compounds were detected within 40min. The practical and effective peak capacity was 1329 and 524, respectively, and the orthogonality was 79.8%. The structures of 21 selected unknown compounds were tentatively characterized by mass spectrometry, and 8 of them were discovered from G. uralensis for the first time. The mobile phase-dependent 2DLC/MS system could benefit the separation and characterization of natural products in complicated herbal extracts.

  2. Recalled separation anxiety and gender atypicality in childhood: a study of Canadian heterosexual and homosexual men and women.

    PubMed

    Vanderlaan, Doug P; Gothreau, Laura M; Bartlett, Nancy H; Vasey, Paul L

    2011-12-01

    The current study tested the hypothesis that elevated childhood separation anxiety is associated with female-typical childhood behavior and identity by comparing retrospective reports of heterosexual and homosexual men and women (N = 399). Participants completed measures of recalled childhood separation anxiety and childhood gender-atypical behavior and identity. Heterosexual men reported significantly less childhood separation anxiety relative to all other groups. Childhood gender atypicality was significantly positively correlated with childhood separation anxiety among homosexual men, but not among members of other participant groups. Discussion focused on the implications of these findings for the proposed hypothesis as well as future directions for research examining the bases of developmental associations among sex, sexual orientation, gender atypicality, and childhood separation anxiety.

  3. Development of bacteriorhodopsin analogues and studies of charge separated excited states in the photoprocesses of linear polyenes.

    PubMed

    Singh, Anil K; Hota, Prasanta K

    2007-01-01

    Development of bacteriorhodopsin (bR) analogues employing chromophore substitution technique for the purpose of characterizing the binding site of bR and generating bR analogues with novel opto-electronic properties for applications as photoactive element in nanotechnical devices are described. Additionally, the photophysical and photochemical properties of variously substituted diarylpolyenes as models of photobiologically relevant linear polyenes are discussed. The role of charge separated dipolar excited states in the photoprocesses of linear polyenes is highlighted.

  4. Distress, support, and relationship satisfaction during military-induced separations: a longitudinal study among spouses of Dutch deployed military personnel.

    PubMed

    Andres, Manon

    2014-02-01

    The aim of this study was to examine (a) how life stress, work-family conflict, social support, psychological distress, and relationship satisfaction develop over the course of military-induced separations; (b) what best predicts relationship satisfaction after being separated for several months; and (c) whether the effects were mediated by spousal interaction. Longitudinal data were collected among 153 spouses of Dutch military personnel before, during, and after military-induced separations. Analyses demonstrated a significant decrease in relationship satisfaction, psychological distress, and social support over time. Controlling for predeployment levels of relationship satisfaction, work-family conflict, social support, psychological distress, and spousal interaction made significant contributions to the explanation of relationship satisfaction after military-induced separations. However, the effects on relationships varied for each stage of the work-related spousal separation. Hence, clinical implications for psychological service delivery suggested by these findings are impacted by the stage of the work-related spousal separation. Specifically, before the separation, services might focus upon balancing work and family demands; during the separation, services that facilitate building networks are important; and finally, communication remains the key service focus upon reunion.

  5. Brief characterization of muskrat (Ondatra zibethicus) immunoglobulin G (IgG) separated from serum on protein A.

    PubMed

    Borucinska, J D; Ayoub, I; Garmendia, A E

    1996-10-01

    Muskrat (Ondatra zibethicus) immunoglobulin fraction was separated from whole serum by Protein A Sepharose chromatography. In serum electrophoresis, this fraction had a gamma motility; when electrophoresed on a polyacrylamide gel with sodium dodecyl sulfate it resolved into two protein bands of approximately 52 and 25 kilodaltons, respectively. These bands were consistent with molecular weights of known heavy and light chains of immunoglobulin G (IgG) in other closely related species. Furthermore, the putative muskrat immunoglobulins had a strong cross-reactivity with mouse IgG1, IgG3, and kappa chain in an enzyme-linked immunosorbent assay. We propose, that the proteins bound to the Protein A Sepharose represent muskrat immunoglobulins of the IgG class.

  6. Separate disciplines: The study of behavior and the study of the psyche

    PubMed Central

    Fraley, Lawrence E.; Vargas, Ernest A.

    1986-01-01

    The study of behavior differs fundamentally from the study of the psyche and logically cannot share the same discipline. However, while disciplines might be defined through technical exercises, they function through exercises of political power. The evolution of a discipline, though based on field and laboratory data interpreted within a specific paradigm and justified publicity by its utility to solve personal and social problems, follows a course of development in the political arenas of the academies and the professions. We happen to have a discipline, roughly connoted by the label “behavior analysis,” without an academic home (the present ones haphazardly tolerate our activities), without a professional organization (the present one lobbies only “for behavior analysis”), and without a true professional name (the present one implies an approach not a discipline). No scientific community lasts long without a supporting professional infrastructure. In explicitly asserting ourselves as a discipline, we confront a number of difficult issues such as continuing to work in departments antithetical to behaviorism and a number of problems such as what we call ourselves to identify our professional and scientific concerns. (For example, we need a term descriptive of our science in its broad sense. That term is not psychology. Too many people persist in maintaining its commitment to cognitivism. On whatever term we agree, “behavior” should constitute its stem, for our efforts focus there, not in the putative underlying psyche or its current cognitive update.) The focus of our concerns and the solutions of our problems rest on one issue: Will our discipline prosper most as a branch of psychology or as an independent discipline? Slowly, but surely, our actions demonstrate that the latter is the preferred option, but these actions, though fortuitous, occur almost by accident. By specifically programming to achieve an independent professional status we increase the

  7. Characterization and mechanical separation of metals from computer Printed Circuit Boards (PCBs) based on mineral processing methods.

    PubMed

    Sarvar, Mojtaba; Salarirad, Mohammad Mehdi; Shabani, Mohammad Amin

    2015-11-01

    In this paper, a novel mechanical process is proposed for enriching metal content of computer Printed Circuit Boards (PCBs). The PCBs are crushed and divided into three different size fractions namely: -0.59, +0.59 to 1.68 and +1.68 mm. Wet jigging and froth flotation methods are selected for metal enrichment. The coarse size fraction (+1.68 mm) is processed by jigging. The plastic free product is grinded and screened. The oversized product is separated as the first concentrate. It was rich of metal because the grinding process was selective. The undersized product is processed by froth flotation. Based on the obtained results, the middle size fraction (+0.59 to 1.68 mm) and the small size fraction (-0.59 mm) are processed by wet jigging and froth flotation respectively. The wet jigging process is optimized by investigating the effect of pulsation frequency and water flow rate. The results of examining the effect of particle size, solid to liquid ratio, conditioning time and using apolar collector showed that collectorless flotation is a promising method for separating nonmetals of PCBs. 95.6%, 97.5% and 85% of metal content of coarse size, middle size and small size fraction are recovered. The grades of obtained concentrates were 63.3%, 92.5% and 75% respectively. The total recovery is calculated as 95.64% and the grade of the final concentrate was 71.26%. Determining the grade of copper and gold in the final product reveals that 4.95% of copper and 24.46% of gold are lost during the concentration. The major part of the lost gold is accumulated in froth flotation tail.

  8. 300-FF-1 Operable Unit physical separation of soils pilot plant study

    SciTech Connect

    Freeman-Pollard, J.R.

    1994-01-15

    Alternative Remedial Technologies, Inc. (ART) was selected in a competitive selection process to conduct a pilot study for the physical separation of soils in the North Process Pond of the 300 Area at the Hanford Site. In January 1994, ART mobilized its 15 tons-per-hour pilot plant to the site. The plant was initially staged in a commercial area to allow for pretest inspections and minor modifications. The plant was specifically designed for use as a physical separations unit and consisted of a feed hopper, wet screens, hydrocyclones, as well as settling and dewatering equipment. The plant was supported in the field with prescreening equipment, mobile generators, air compressors, and water storage tanks. The plant was moved into the surface contamination area on March 24, 1994. The testing was conducted during the period March 23, 1994 through April 13, 1994. Two soil types were treated during the testing: a natural soil contaminated with low levels of uranium, cesium, cobalt, and heavy metals, and a natural soil contaminated with a uranium carbonate material that was visually recognizable by the presence of a green sludge material in the soil matrix. The ``green`` material contained significantly higher levels of the same contaminants. Both source materials were treated by the plant in a manner that fed the material, produced clean gravel and sand fractions, and concentrated the contaminants in a sludge cake. Process water was recycled during the operations. The testing was extremely successful in that for both source waste streams, it was demonstrated that volume reductions of greater than 90% could be achieved while also meeting the test performance criteria. The volume reduction for the natural soils averaged a 93.8%, while the ``green`` soils showed a 91.4% volume reduction.

  9. Improved tryptic digestion assisted with an acid-labile anionic surfactant for the separation and characterization of glycopeptide glycoforms of a proteolytic-resistant glycoprotein by capillary electrophoresis time-of-flight mass spectrometry.

    PubMed

    Barroso, Albert; Giménez, Estela; Benavente, Fernando; Barbosa, José; Sanz-Nebot, Victoria

    2016-04-01

    Certain glycoproteins are rather difficult to digest due to compacted tertiary or quaternary structures. In a previous study, a capillary LC coupled to TOF-MS (μLC-TOF-MS) method was developed for the detection and characterization of the glycopeptide glycoforms of human transferrin (Tf), a proteolytic resistant glycoprotein, in serum samples. After immunoaffinity purification, Tf was digested with trypsin in the presence of RapiGest(®) and μLC-TOF-MS analyses permitted to detect the N413 and N611 glycopeptide glycoforms. Conversely, the use of this surfactant, albeit mandatory to quantitatively digest the isolated Tf, proved detrimental to CE-TOF-MS analysis due to its interaction with the inner surface of the silica capillary walls. As CE is usually regarded as an interesting alternative to other separation techniques (low consumption of reagents, excellent separation efficiency, and reduced analysis times), in this work, the undesirable interferences of the surfactant have been removed to allow the correct separation and detection of Tf glycoforms by CE-TOF-MS. Moreover, the digestion protocol described by the RapiGest(®) manufacturer has been modified to minimize desialylation of Tf glycopeptide glycoforms. The new developed CE-TOF-MS methodology has been then compared with the former μLC-TOF-MS by means of sensitivity and separation efficiency of Tf glycopeptide glycoforms in the standard glycoprotein. Additionally, Tf glycopeptide glycoforms from serum of healthy volunteers and patients with congenital disorders of glycosylation have also been analyzed following the developed methodology.

  10. [Historical study of separation technology innovation in the field of pharmaceutical science].

    PubMed

    Yamakawa, Koji; Nishitani, Kiyoshi

    2003-01-01

    The separation of organic compounds has been carried out using the method of distillation and recrystallization since the 17th century.1st separation technology innovation (1950s to 1960s). After World War II, the science of separating organic compounds evolved to the use of paper or column chromatography. 2nd separation technology innovation (1960s to 1980s). In the 1960s, thin-layer chromatograpy (TLC) was developed. TLC is a convenient analytical technique for organic compounds. Separation methods for organic compounds using column chromatography and preparative TLC were carried out as practical applications. Gas chromatography (GC) was also introduced in the 1960s. GC is a useful analytical method for a mixture of various volatile organic compounds. Many GC instruments with new kinds of sensors were developed. Gas chromatography of nonbenzenoid organometallic compounds and metal complexes was successfully conducted by the author. 3rd separation technology innovation (1980s to 1990s). In the 1980s, high-performance liquid-chromatography (HPLC) was developed. HPLC analytical methods were useful for various kinds of organic compounds. In the 1990s, LC-MS and LC-NMR instruments were introduced for biomedical products. 4th separation technology innovation (1990s to present). Several new ionization methods for mass-spectrometry (electrospray, matrix-aided lazer desorption ionization, etc) are applied for proteins and biomedical products. Several new separation technologies (supercritical field chromatography, capillary electrophoresis, field-flow fractionization, etc.) are now being developed.

  11. The Separation-Individuation Process and Culture: A Study on Taiwan's College Students.

    ERIC Educational Resources Information Center

    Tam, Wai-Cheong Carl; Shiah, Yung-Jong; Chiang, Shih-Kuang

    The separation-individuation process of individuals is mediated by cultural factors of the society to which the individuals belong. Since the Chinese culture emphasizes collectivism rather than the individualism of Western culture, it is believed that there are differences in the separation-individuation process of individuals between the two…

  12. Separated Shoulder

    MedlinePlus

    Separated shoulder Overview By Mayo Clinic Staff A separated shoulder is an injury to the ligaments that hold your collarbone (clavicle) to your shoulder blade. In a mild separated shoulder, the ligaments ...

  13. Carrier Separation and Transport in Perovskite Solar Cells Studied by Nanometre-Scale Profiling of Electrical Potential

    DOE PAGES

    Jiang, Chun-Sheng; Yang, Mengjin; Zhou, Yuanyuan; ...

    2015-09-28

    Organometal–halide perovskite solar cells have greatly improved in just a few years to a power conversion efficiency exceeding 20%. This technology shows unprecedented promise for terawatt-scale deployment of solar energy because of its low-cost, solution-based processing and earth-abundant materials. We have studied charge separation and transport in perovskite solar cells—which are the fundamental mechanisms of device operation and critical factors for power output—by determining the junction structure across the device using the nanoelectrical characterization technique of Kelvin probe force microscopy. Moreover, the distribution of electrical potential across both planar and porous devices demonstrates p–n junction structure at the TiO2/perovskite interfacesmore » and minority-carrier diffusion/drift operation of the devices, rather than the operation mechanism of either an excitonic cell or a p-i-n structure. When we combined the potential profiling results with solar cell performance parameters measured on optimized and thickened devices, we find that carrier mobility is a main factor that needs to be improved for further gains in efficiency of the perovskite solar cells.« less

  14. Carrier separation and transport in perovskite solar cells studied by nanometre-scale profiling of electrical potential

    NASA Astrophysics Data System (ADS)

    Jiang, Chun-Sheng; Yang, Mengjin; Zhou, Yuanyuan; To, Bobby; Nanayakkara, Sanjini U.; Luther, Joseph M.; Zhou, Weilie; Berry, Joseph J.; van de Lagemaat, Jao; Padture, Nitin P.; Zhu, Kai; Al-Jassim, Mowafak M.

    2015-09-01

    Organometal-halide perovskite solar cells have greatly improved in just a few years to a power conversion efficiency exceeding 20%. This technology shows unprecedented promise for terawatt-scale deployment of solar energy because of its low-cost, solution-based processing and earth-abundant materials. We have studied charge separation and transport in perovskite solar cells--which are the fundamental mechanisms of device operation and critical factors for power output--by determining the junction structure across the device using the nanoelectrical characterization technique of Kelvin probe force microscopy. The distribution of electrical potential across both planar and porous devices demonstrates p-n junction structure at the TiO2/perovskite interfaces and minority-carrier diffusion/drift operation of the devices, rather than the operation mechanism of either an excitonic cell or a p-i-n structure. Combining the potential profiling results with solar cell performance parameters measured on optimized and thickened devices, we find that carrier mobility is a main factor that needs to be improved for further gains in efficiency of the perovskite solar cells.

  15. Carrier separation and transport in perovskite solar cells studied by nanometre-scale profiling of electrical potential.

    PubMed

    Jiang, Chun-Sheng; Yang, Mengjin; Zhou, Yuanyuan; To, Bobby; Nanayakkara, Sanjini U; Luther, Joseph M; Zhou, Weilie; Berry, Joseph J; van de Lagemaat, Jao; Padture, Nitin P; Zhu, Kai; Al-Jassim, Mowafak M

    2015-09-28

    Organometal-halide perovskite solar cells have greatly improved in just a few years to a power conversion efficiency exceeding 20%. This technology shows unprecedented promise for terawatt-scale deployment of solar energy because of its low-cost, solution-based processing and earth-abundant materials. We have studied charge separation and transport in perovskite solar cells-which are the fundamental mechanisms of device operation and critical factors for power output-by determining the junction structure across the device using the nanoelectrical characterization technique of Kelvin probe force microscopy. The distribution of electrical potential across both planar and porous devices demonstrates p-n junction structure at the TiO2/perovskite interfaces and minority-carrier diffusion/drift operation of the devices, rather than the operation mechanism of either an excitonic cell or a p-i-n structure. Combining the potential profiling results with solar cell performance parameters measured on optimized and thickened devices, we find that carrier mobility is a main factor that needs to be improved for further gains in efficiency of the perovskite solar cells.

  16. Carrier Separation and Transport in Perovskite Solar Cells Studied by Nanometre-Scale Profiling of Electrical Potential

    SciTech Connect

    Jiang, Chun-Sheng; Yang, Mengjin; Zhou, Yuanyuan; To, Bobby; Nanayakkara, Sanjini U.; Luther, Joseph M.; Zhou, Weilie; Berry, Joseph J.; van de Lagemaat, Jao; Padture, Nitin P.; Zhu, Kai; Al-Jassim, Mowafak M.

    2015-09-28

    Organometal–halide perovskite solar cells have greatly improved in just a few years to a power conversion efficiency exceeding 20%. This technology shows unprecedented promise for terawatt-scale deployment of solar energy because of its low-cost, solution-based processing and earth-abundant materials. We have studied charge separation and transport in perovskite solar cells—which are the fundamental mechanisms of device operation and critical factors for power output—by determining the junction structure across the device using the nanoelectrical characterization technique of Kelvin probe force microscopy. Moreover, the distribution of electrical potential across both planar and porous devices demonstrates p–n junction structure at the TiO2/perovskite interfaces and minority-carrier diffusion/drift operation of the devices, rather than the operation mechanism of either an excitonic cell or a p-i-n structure. When we combined the potential profiling results with solar cell performance parameters measured on optimized and thickened devices, we find that carrier mobility is a main factor that needs to be improved for further gains in efficiency of the perovskite solar cells.

  17. Plasma characterization studies for materials processing

    SciTech Connect

    Pfender, E.; Heberlein, J.

    1995-12-31

    New applications for plasma processing of materials require a more detailed understanding of the fundamental processes occurring in the processing reactors. We have developed reactors offering specific advantages for materials processing, and we are using modeling and diagnostic techniques for the characterization of these reactors. The emphasis is in part set by the interest shown by industry pursuing specific plasma processing applications. In this paper we report on the modeling of radio frequency plasma reactors for use in materials synthesis, and on the characterization of the high rate diamond deposition process using liquid precursors. In the radio frequency plasma torch model, the influence of specific design changes such as the location of the excitation coil on the enthalpy flow distribution is investigated for oxygen and air as plasma gases. The diamond deposition with liquid precursors has identified the efficient mass transport in form of liquid droplets into the boundary layer as responsible for high growth, and the chemical properties of the liquid for the film morphology.

  18. Separation and characterization of bufadienolides in toad skin using two-dimensional normal-phase liquid chromatography×reversed-phase liquid chromatography coupled with mass spectrometry.

    PubMed

    Zhang, Yun; Jin, Hongli; Li, Xiaolong; Zhao, Jianqiang; Guo, Xiujie; Wang, Jixia; Guo, Zhimou; Zhang, Xiuli; Tao, Yanduo; Liu, Yanfang; Chen, Deliang; Liang, Xinmiao

    2016-07-15

    Bufadienolides possess various bioactivities especially antitumor. Due to the high structural diversity, the separation of bufadienolides often suffers from coelution problem on conventional RP columns. In this work, an off-line two-dimensional normal-phase liquid chromatography×reversed-phase liquid chromatography (2D-NPLC×RPLC) method was developed to separate and characterize bufadienolides in toad skin. Several RP and NP columns were evaluated with five reference bufadienlides. The XUnion C18 and XAmide columns exhibited superior chromatographic performances for bufadienlide separation, and were selected in RPLC and NPLC, respectively. RPLC was used in the second-dimension for the good compatibility with MS, while NPLC was adopted in the first-dimension. The orthogonality of the 2D-NPLC×RPLC system was investigated by the geometric approach using fifteen bufadienolide mixtures. The result was 49.6%, demonstrating reasonable orthogonality of this 2D-LC system. By combining the 2D-LC system with MS, 64 bufadienlides including 33 minor ones and 11 pairs of isomers in toad skin were identified. This off-line 2D-NPLC×RPLC allowed to solve the coelution problem of bufadienlides in one-dimension RPLC, and thus facilitated the identification significantly.

  19. Morphological and molecular characterization of the metacercaria of Paragonimus caliensis, as a separate species from P. mexicanus in Costa Rica.

    PubMed

    Hernández-Chea, Roderico; Jiménez-Rocha, Ana Eugenia; Castro, Ruth; Blair, David; Dolz, Gaby

    2017-04-01

    The trematode Paragonimus mexicanus is the etiological agent of paragonimiasis, a food-borne zoonotic disease in Latin America. This species, as well as Paragonimus caliensis, have been reported from Costa Rica, but it is not known if the two are synonymous. Two types of Paragonimus metacercariae from freshwater pseudothelphusid crabs from several localities in Costa Rica were recognized by light microscopy. Morphologically, these corresponded to descriptions of P. mexicanus and P. caliensis. Metacercariae of the former species lacked a membrane or cyst and their bodies were yellow in color. Those of P. caliensis were contained in a transparent thin cyst and were pink in color. Morphotypes of metacercariae were determined using scanning electron microscopy (SEM). Based on the number and distribution of papillae in the ventral sucker, three morphotypes were found for P. mexicanus and two for P. caliensis. Analysis of DNA sequences (nuclear ribosomal 28S and ITS2 genes, and partial mitochondrial cox1 gene) confirmed the presence of P. mexicanus and provided the first molecular data for P. caliensis. The two species are phylogenetically distinct from each other and distant from the Asian species. The confirmation of P. caliensis as a separate species from P. mexicanus raises several questions about the ecology, biological diversity, and epidemiology of the genus Paragonimus in Costa Rica.

  20. Effect of UV-ozone treatment on poly(dimethylsiloxane) membranes: surface characterization and gas separation performance.

    PubMed

    Fu, Ywu-Jang; Qui, Hsuan-zhi; Liao, Kuo-Sung; Lue, Shingjiang Jessie; Hu, Chien-Chieh; Lee, Kueir-Rarn; Lai, Juin-Yih

    2010-03-16

    A thin SiO(x) selective surface layer was formed on a series of cross-linked poly(dimethylsiloxane) (PDMS) membranes by exposure to ultraviolet light at room temperature in the presence of ozone. The conversion of the cross-linked polysiloxane to SiO(x) was monitored by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray (EDX) microanalysis, contact angle analysis, and atomic force microscopy (AFM). The conversion of the cross-linked polysiloxane to SiO(x) increased with UV-ozone exposure time and cross-linking agent content, and the surface possesses highest conversion. The formation of a SiO(x) layer increased surface roughness, but it decreased water contact angle. Gas permeation measurements on the UV-ozone exposure PDMS membranes documented interesting gas separation properties: the O(2) permeability of the cross-linked PDMS membrane before UV-ozone exposure was 777 barrer, and the O(2)/N(2) selectivity was 1.9; after UV-ozone exposure, the permeability decreased to 127 barrer while the selectivity increased to 5.4. The free volume depth profile of the SiO(x) layer was investigated by novel slow positron beam. The results show that free volume size increased with the depth, yet the degree of siloxane conversion to SiO(x) does not affect the amount of free volume.

  1. An experimental study of ice-bed separation during glacial sliding

    NASA Astrophysics Data System (ADS)

    Petersen, Benjamin Brett

    Separation of sliding ice from hard beds plays a central role in theories of subglacial hydrology, sediment transport, and quarrying of subglacial bedrock. Despite a half-century of interest in cavities at glacier beds, there are no data establishing relationships among steady cavity size, bed geometry, sliding speed, and effective pressure. Field studies are complicated by unsteady behavior and various factors that are poorly known, including the local effective pressure at the bed, bedrock geometry, and cavity size. A laboratory ring-shear device allows sliding and ice-bed separation to be studied experimentally. The apparatus drags a ring of ice (0.9 m O.D., 0.2 m wide, 0.2 m thick) across a stepped, rigid bed. The steps are 0.18 m long and 0.027 m high along the ice-ring centerline, with treads inclined uniformly 8° up-flow. Sliding speed and effective pressure are controlled, while cavity volume and bed and wall temperatures are recorded. A glycol-water mixture, which is regulated to +/-0.01°C with an external circulator, keeps ice at the melting temperature and melt rates low. Post-experimental measurements of the ice ring's basal topography provide reconstructions of cavity geometries. Ice c-axis orientations are measured throughout the ice ring using a Rigsby (universal) stage. Monotonic cavity growth towards a larger, steady size in response to increased sliding speeds was expected. Instead, cavities initially grew past their steady-state volume, followed by a series of progressively dampened oscillations above and below steady dimensions before reaching a steady size. Steady-state cavities initiated at step edges and had slightly curved roofs. Experimental cavity lengths were accurately predicted by a model based on Kamb's (1987) theory of glacial surging and a new model incorporating Nye's (1953) borehole closure theory. The c-axes of ice crystals at shear strains ≥ 1 formed steeply inclined, multi-maximum fabrics similar to those measured in ice at

  2. Purification and characterization of large and small subunits of ribulose 1,5-bisphosphate carboxylase expressed separately in Escherichia coli.

    PubMed

    Smrcka, A V; Ramage, R T; Bohnert, H J; Jensen, R G

    1991-04-01

    Procedures were developed for 95 and 80% purification to homogeneity of the large subunit (L) and small subunit (S) of ribulose 1,5-bisphosphate carboxylase/oxygenase (L8S8) from Synechococcus PCC 6301, each expressed separately in Escherichia coli. Purified L had a low specific activity in the absence of S (0.075 mumol CO2 fixed/mg holoenzyme/min). Following elution on a Pharmacia Superose 6 or 12 gel filtration column, 50% of the purified L appeared as the octamer, L8. The rest was in equilibrium with lower polymeric species and/or was retained on the column. Large and small subunits assembled rapidly into the L8S8 holoenzyme that had high specific activities, 6.2 and 3.1 mumol CO2 fixed/mg holoenzyme/min for the homologous Synechococcus L8S8 and the hybrid Synechococcus L-pea S L8S8, respectively. The CO2 dependence for carbamylation of L8 was compared to that of L8S8 as a function of pH and CO2 concentration. The pH dependence indicated an apparent pKa for L8 of 8.28 and for L8S8 of 8.15, suggesting that S may influence the pKa of the lysine involved in carbamylation. The Kact for CO2 at pH 8.4 were similar for L8 (13.5 microM) and L8S8 (15.5 microM). L8 bound 2-[14C]carboxy-D-arabinitol 1,5-bisphosphate (CABP) tightly so that most of the bound [14C]CABP survived gel filtration. A major amount of the L8-[14C]CABP complex appeared as larger polymeric aggregates when eluted in the presence of E. coli protein.

  3. Gel Separation of Isozymes To Study Relatedness of Common Bean Cultivars from ARound the World.

    ERIC Educational Resources Information Center

    Hammond, Paul; Oxley, Mary; Ealing, Ben

    2002-01-01

    Explains a three week laboratory experiment on the gel separation of peroxidase, which is the most well-known isozyme, from beans. Includes suggestions on the laboratory management. (Contains 13 references.) (YDS)

  4. Experimental study and numerical simulation of flow separation control with pulsed nanosecond discharge actuator

    NASA Astrophysics Data System (ADS)

    Correale, Guiseppe; Popov, Ilya; Nikipelov, Andrey; Pancheshnyi, Sergey; Hulshoff, Seo; Veldhuis, Leo; Starikovskiy, Andrey; neqlab Team; TUDelft Team

    2011-10-01

    Active flow separation control with a nanosecond pulse plasma actuator, which is essentially a simple electrode system on the surface of an airfoil, introducing low-energy gas discharge into the boundary layer, with little extra weight and no mechanical parts, was performed in wind-tunnel experiments on various airfoil models. In stall conditions the significant lift increase up to 30% accompanied by drag reduction (up to 3 times) was observed. The critical angle of attack shifted up to 5{7 degrees. Schlieren imaging shown the shock wave propagation and formation of large-scale vortex structure in the separation zone, which led to separation elimination. The experimental work is supported by numerical simulations of the phenomena. The formation of vortex similar to that observed in experiments was simulated in the case of laminar leading edge separation. Model simulations of free shear layer shown intensification of shear layer instabilities due to shock wave to shear layer interaction.

  5. Separation of polymeric topoisomers in a microchannel device: a Monte Carlo study

    NASA Astrophysics Data System (ADS)

    Tessier, Frederic; Slater, Gary W.

    2001-03-01

    Polymer molecules come in a variety of topological flavors, from simple linear chains to branched, ring, or even more intricate knotted or catenane structures. This aspect of polymer chains is increasingly recognized as a key factor in biological processes, in particular those associated with DNA manipulation; specialized enzymes regularly induce DNA topological changes in the course of replication, recombination and packaging. Separating molecules of different topologies is important to assess the activity of those enzymes, and it has previously been achieved via gel electrophoresis. However, in the wake of the current trend towards lab-on-a-chip technologies, we present simulation results for the separation of topoisomers in an entropic trap array, a microdevice etched on a silicon wafer recently used to separate DNA by size(J. Han, S. W. Turner and H. G. Craighead, Phys. Rev. Lett. 83), 1688 (1999). We show that topology-based separation for linear, ring and branched polymers is indeed possible in such a device.

  6. Hydrologic Characterization Study at Wildcat Fault Zone

    NASA Astrophysics Data System (ADS)

    Karasaki, K.; Onishi, C. T.; Goto, J.; Moriya, T.; Ueta, K.; Kiho, K.

    2011-12-01

    A dedicated field site has been developed to further the understanding of, and to develop the characterization technology for, fault zone hydrology in the hills east of Berkeley, California across the Wildcat Fault. The Wildcat is believed to be a strike-slip fault and a member of the Hayward Fault System, with over 10 km of displacement. So far, several ~2-4-m deep trenches were cut, a number of surface-based geophysical surveys were conducted, and four ~150-m deep fully cored boreholes were drilled at the site; one on the east side and two on the west side of the suspected fault trace. The inclined fourth hole was drilled to penetrate the Wildcat. Geologic analysis results from these trenches and boreholes indicated that the geology was not always what was expected: while confirming some earlier, published conclusions about Wildcat, they have also led to some unexpected findings. The lithology at the Wildcat Fault area mainly consists of chert, shale, silt and sandstone, extensively sheared and fractured with gouge and cataclasite zones observed at several depths. Wildcat near the field site appears to consist of multiple fault planes with the major fault planes filled with unconsolidated pulverized rock instead of clay gouge. The pressure and temperature distributions indicate a downward hydraulic gradient and a relatively large geothermal gradient. Various types of borehole logging were conducted but there were no obvious correlations between boreholes or to hydrologic properties. Using the three other boreholes as observation wells, hydrologic cross-hole pumping tests were conducted in the fourth borehole. The hydraulic test data suggest the dual properties of the hydrologic structure of the fault zone: high permeability along the plane and low permeability across it, and the fault planes may be compartmentalizing aquifers. No correlation was found between fracture frequency and flow. Long term pressure monitoring over multiple seasons was shown to be very

  7. Ultracapacitor separator

    DOEpatents

    Wei, Chang; Jerabek, Elihu Calvin; LeBlanc, Jr., Oliver Harris

    2001-03-06

    An ultracapacitor includes two solid, nonporous current collectors, two porous electrodes separating the collectors, a porous separator between the electrodes and an electrolyte occupying the pores in the electrodes and separator. The electrolyte is a polar aprotic organic solvent and a salt. The porous separator comprises a wet laid cellulosic material.

  8. Sibutramine characterization and solubility, a theoretical study

    NASA Astrophysics Data System (ADS)

    Aceves-Hernández, Juan M.; Nicolás Vázquez, Inés; Hinojosa-Torres, Jaime; Penieres Carrillo, Guillermo; Arroyo Razo, Gabriel; Miranda Ruvalcaba, René

    2013-04-01

    Solubility data from sibutramine (SBA) in a family of alcohols were obtained at different temperatures. Sibutramine was characterized by using thermal analysis and X-ray diffraction technique. Solubility data were obtained by the saturation method. The van't Hoff equation was used to obtain the theoretical solubility values and the ideal solvent activity coefficient. No polymorphic phenomena were found from the X-ray diffraction analysis, even though this compound is a racemic mixture of (+) and (-) enantiomers. Theoretical calculations showed that the polarisable continuum model was able to reproduce the solubility and stability of sibutramine molecule in gas phase, water and a family of alcohols at B3LYP/6-311++G (d,p) level of theory. Dielectric constant, dipolar moment and solubility in water values as physical parameters were used in those theoretical calculations for explaining that behavior. Experimental and theoretical results were compared and good agreement was obtained. Sibutramine solubility increased from methanol to 1-octanol in theoretical and experimental results.

  9. Process study and exergy analysis of a novel air separation process cooled by LNG cold energy

    NASA Astrophysics Data System (ADS)

    Xu, Wendong; Duan, Jiao; Mao, Wenjun

    2014-02-01

    In order to resolve the problems of the current air separation process such as the complex process, cumbersome operation and high operating costs, a novel air separation process cooled by LNG cold energy is proposed in this paper, which is based on high-efficiency heat exchanger network and chemical packing separation technology. The operating temperature range of LNG cold energy is widened from 133K-203K to 113K-283K by high-efficiency heat exchanger network and air separation pressure is declined from 0.5MPa to about 0.35MPa due to packing separation technology, thereby greatly improve the energy efficiency. Both the traditional and novel air separation processes are simulated with air handling capacity of 20t·h-1. Comparing with the traditional process, the LNG consumption is reduced by 44.2%, power consumption decrease is 211.5 kWh per hour, which means the annual benefit will be up to 1.218 million CNY. And the exergy efficiency is also improved by 42.5%.

  10. Detailed characterization of the kinetic performance of first and second generation silica monolithic columns for reversed-phase chromatography separations.

    PubMed

    Cabooter, Deirdre; Broeckhoven, Ken; Sterken, Roman; Vanmessen, Alison; Vandendael, Isabelle; Nakanishi, Kazuki; Deridder, Sander; Desmet, Gert

    2014-01-17

    The kinetic performance of commercially available first generation and prototype second generation silica monoliths has been investigated for 2.0mm and 3.0-3.2mm inner diameter columns. It is demonstrated that the altered sol-gel process employed for the production of second generation monoliths results in structures with a smaller characteristic size leading to an improved peak shape and higher efficiencies. The permeability of the columns however, decreases significantly due to the smaller throughpore and skeleton sizes. Scanning electron microscopy pictures suggest the first generation monoliths have cylindrical skeleton branches, whereas the second generation monoliths rather have skeleton branches that resemble a single chain of spherical globules. Using recently established correlations for the flow resistance of cylindrical and globule chain type monolithic structures, it is demonstrated that the higher flow resistance of the second generation monoliths can be entirely attributed to their smaller skeleton sizes, which is also evident from the external porosity that is largely the same for both monolith generations (ɛe∼0.65). The recorded van Deemter plots show a clear improvement in efficiency for the second generation monoliths (minimal plate heights of 13.6-14.1μm for the first and 6.5-8.2μm for the second generation, when assessing the plate count using the Foley-Dorsey method). The corresponding kinetic plots, however, indicate that the much reduced permeability of the second generation monoliths results in kinetic performances (time needed to achieve a given efficiency) which are only better than those of the first generation for plate counts up to N∼45,000. For more complex samples (N≥50,000), the first generation monoliths can intrinsically still provide faster analysis due to their high permeability. It is also demonstrated that - despite the improved efficiency of the second generation monoliths in the practical range of separations (N=10

  11. Performance of Reynolds Averaged Navier-Stokes Models in Predicting Separated Flows: Study of the Hump Flow Model Problem

    NASA Technical Reports Server (NTRS)

    Cappelli, Daniele; Mansour, Nagi N.

    2012-01-01

    Separation can be seen in most aerodynamic flows, but accurate prediction of separated flows is still a challenging problem for computational fluid dynamics (CFD) tools. The behavior of several Reynolds Averaged Navier-Stokes (RANS) models in predicting the separated ow over a wall-mounted hump is studied. The strengths and weaknesses of the most popular RANS models (Spalart-Allmaras, k-epsilon, k-omega, k-omega-SST) are evaluated using the open source software OpenFOAM. The hump ow modeled in this work has been documented in the 2004 CFD Validation Workshop on Synthetic Jets and Turbulent Separation Control. Only the baseline case is treated; the slot flow control cases are not considered in this paper. Particular attention is given to predicting the size of the recirculation bubble, the position of the reattachment point, and the velocity profiles downstream of the hump.

  12. Pore size, zinc penetration, and zinc diffusion studies on PPQ/CA separators. Research and development report

    SciTech Connect

    Angres, I.; Parkhurst, W.

    1981-02-02

    Studies were performed of some properties of co-polymeric polyphenylquinoxaline/cellulose acetate (PPQ/CA-60/40) membranes that are candidate separator materials for secondary alkaline batteries. Pore size measurements were obtained by bubble pressure, mercury porosimetry and electron microscopy methods. Zinc penetration measurements and measurements of zinc ion diffusion through the membrane were obtained in aqueous potassium hydroxide media using standardized electrolysis methods. For comparison purposes, dendrite penetration and zinc diffusion measurements were also obtained for two conventional cellulosic separator materials. It was concluded that the methods chosen are valid and useful for assessing the quality of separator materials. It was also concluded that PPQ/CA-60/40 membranes compare favorably with conventional separator materials.

  13. Separating Leaves from Trunks and Branches with Dual-Wavelength Terrestrial Lidar Scanning: Improving Canopy Structure Characterization in 3-D Space

    NASA Astrophysics Data System (ADS)

    Li, Z.; Strahler, A. H.; Schaaf, C.; Howe, G.; Martel, J.; Hewawasam, K.; Douglas, E. S.; Chakrabarti, S.; Cook, T.; Paynter, I.; Saenz, E.; Wang, Z.; Yang, X.; Yao, T.; Zhao, F.; Woodcock, C.; Jupp, D.; Schaefer, M.; Culvenor, D.; Newnham, G.; Lowell, J.

    2013-12-01

    Leaf area index (LAI) is an important parameter characterizing forest structure, used in models regulating the exchange of carbon, water and energy between the land and the atmosphere. However, optical methods in common use cannot separate leaf area from the area of upper trunks and branches, and thus retrieve only plant area index (PAI), which is adjusted to LAI using an appropriate empirical woody-to-total index. An additional problem is that the angular distributions of leaf normals and normals to woody surfaces are quite different, and thus leafy and woody components project quite different areas with varying zenith angle of view. This effect also causes error in LAI retrieval using optical methods. Full-waveform scans at both the NIR (1064 nm) and SWIR (1548 nm) wavelengths from the new terrestrial Lidar, the Dual-Wavelength Echidna Lidar (DWEL), which pulses in both wavelengths simultaneously, easily separate returns of leaves from trunks and branches in 3-D space. In DWEL scans collected at two different forest sites, Sierra National Forest in June 2013 and Brisbane Karawatha Forest Park in July 2013, the power returned from leaves is similar to power returned from trunks/branches at the NIR wavelength, whereas the power returned from leaves is much lower (only about half as large) at the SWIR wavelength. At the SWIR wavelength, the leaf scattering is strongly attenuated by liquid water absorption. Normalized difference index (NDI) images from the waveform mean intensity at the two wavelengths demonstrate a clear contrast between leaves and trunks/branches. The attached image shows NDI from a part of a scan of an open red fir stand in the Sierra National Forest. Leaves appear light, while other objects are darker.Dual-wavelength point clouds generated from the full waveform data show weaker returns from leaves than from trunks/branches. A simple threshold classification of the NDI value of each scattering point readily separates leaves from trunks and

  14. Characterizing Student Expectations: A Small Empirical Study

    ERIC Educational Resources Information Center

    Warwick, Jonathan

    2016-01-01

    This paper describes the results of a small empirical study (n = 130), in which undergraduate students in the Business Faculty of a UK university were asked to express views and expectations relating to the study of a mathematics. Factor analysis is used to identify latent variables emerging from clusters of the measured variables and these are…

  15. [Study on directional separation of picroside II from extract of traditional Chinese medicine by molecularly imprinted technology].

    PubMed

    Yi, Li-Na; Li, Ke-Qin; Wang, Qiu-Juan; Liu, Qing-Shan; Guo, Qing-Long

    2013-07-01

    Picroside II, separated from Chinese herbal medicine, is an active compound with neroprotective activity. Molecularly imprinted polymers (MIPs) have high affinity toward template molecules synthesized by molecularly imprinted technology for its specific combined sites, which can overcome the shortcomings of traditional separation methods, such as complex operation and low efficiency. In this paper, MIPs were prepared by precipitation polymerization with picroside II as the template molecule, 1-vinylimidazole (1-Vinyl) as functional monomer, ethylene glycol dimethacrylate (EDMA) as cross-linker. The morphology of MIPs was characterized by scanning electronmicroscope (SEM) and its static adsorption capacity was measured by the scatchard equation. The results showed that picroside II MIPs have spherical shape, and most of them are uniform in size. Furthermore, the maximum binding capacity (Q(max)) of MIPs is 3.02 mg x g(-1), higher than that of non-imprinted polymers (NIPs). This result indicated that picroside II MIPs with good morphology and high targeted affinity toward the template molecules can be prepared by precipitation polymerization, which can be used to separate picroside II and its analogies from extract of Chinese herbal medicine. In addition, this method has the advantages of good environment and simple operation, which might offer a novel method for the efficient separation of picroside II in the traditional herbal medicines.

  16. Life cycle assessment of a household solid waste source separation programme: a Swedish case study.

    PubMed

    Bernstad, Anna; la Cour Jansen, Jes; Aspegren, Henrik

    2011-10-01

    The environmental impact of an extended property close source-separation system for solid household waste (i.e., a systems for collection of recyclables from domestic properties) is investigated in a residential area in southern Sweden. Since 2001, households have been able to source-separate waste into six fractions of dry recyclables and food waste sorting. The current system was evaluated using the EASEWASTE life cycle assessment tool. Current status is compared with an ideal scenario in which households display perfect source-separation behaviour and a scenario without any material recycling. Results show that current recycling provides substantial environmental benefits compared to a non-recycling alternative. The environmental benefit varies greatly between recyclable fractions, and the recyclables currently most frequently source-separated by households are often not the most beneficial from an environmental perspective. With optimal source-separation of all recyclables, the current net contribution to global warming could be changed to a net-avoidance while current avoidance of nutrient enrichment, acidification and photochemical ozone formation could be doubled. Sensitivity analyses show that the type of energy substituted by incineration of non-recycled waste, as well as energy used in recycling processes and in the production of materials substituted by waste recycling, is of high relevance for the attained results.

  17. DNS study of large-scale structures in a separated turbulent boundary layer

    NASA Astrophysics Data System (ADS)

    Abe, Hiroyuki; Mizobuchi, Yasuhiro; Matsuo, Yuichi

    2011-11-01

    Direct numerical simulations (DNSs) of a separated flat-plate turbulent boundary layer have been carried out. The inlet data are prescribed by DNSs of a zero-pressure-gradient turbulent boundary layer with the rescaling-recycling method; blowing and suction are imposed at the upper boundary for producing a separation bubble. The Reynolds numbers at the inlet are set to be Reθ =300, 600 and 900, where Reθ is the Reynolds number based on the freestream velocity and the momentum thickness. Particular attention is given to large- scale structures existing in a separated region. Results indicate that large-scale organized structures of the streamwise velocity fluctuation appear in a detached shear layer when a large separated region is formed. The latter structures consist of positive and negative regions alternating in the spanwise direction with a spacing of about 2 ~ 3δ99 (δ99 denotes the 99% boundary layer thickness at the inlet), which become more apparent with increasing Reynolds number. They are most likely associated with large-scale spanwise meandering of the separation line. There is also close relationship between the large-scale structures and vortical structures, the latter tending to form vortex clusters where hairpin-like vortices are also observed.

  18. The experimental study of a high efficiency hydrocyclone for oil/water separation

    SciTech Connect

    Jiang, M.; Jie, H.; Xia, Z.; Ren, F.

    1993-12-31

    Hydrocyclone is a centrifugal separation device. Because of their small size, low mean residence tie and high efficiency, hydrocyclones have a potential attraction for oily sewage treatment on offshore oil platforms and ocean-going vessels. Up to now, there have been many problems to be solved on liquid-liquid hydrocyclones. An experimental rig has been set up in the laboratory at Daqing Petroleum Institute. After the theoretical and experimental research for nearly two years, a high efficiency hydrocyclone has been designed. The effect of key parameters (pressure P, flowrate Q{sub i} and split ratio F, etc.) on separation performance has been examined. Preliminary oil field experiments have been satisfactory. The research work on liquid-liquid separation hydrocyclones has a profound significance.

  19. SRM filament wound case resin characterization studies

    NASA Technical Reports Server (NTRS)

    Chou, L. W.

    1985-01-01

    The amine cured epoxy wet winding resin used in fabrication of the SRM filament wound case is analyzed. High pressure liquid chromatography (HPSC) is utilized extensively to study lot-to-lot variation in both resin and curing agent. The validity of quantitative hplc methodology currently under development in-process resin/catalyst assay is assessed.

  20. Characterizing the ADHD Phenotype for Genetic Studies

    ERIC Educational Resources Information Center

    Stevenson, Jim; Asherson, Phil; Hay, David; Levy, Florence; Swanson, Jim; Thapar, Anita; Willcutt, Erik

    2005-01-01

    The genetic study of ADHD has made considerable progress. Further developments in the field will be reliant in part on identifying the most appropriate phenotypes for genetic analysis. The use of both categorical and dimensional measures of symptoms related to ADHD has been productive. The use of multiple reporters is a valuable feature of the…

  1. Inhibiting the shuttle effect of Li-S battery with a graphene oxide coating separator: Performance improvement and mechanism study

    NASA Astrophysics Data System (ADS)

    Jiang, Yong; Chen, Fang; Gao, Yang; Wang, Yanyan; Wang, Shanshan; Gao, Qiang; Jiao, Zheng; Zhao, Bing; Chen, Zhiwen

    2017-02-01

    In this paper, graphene oxide (GO) is integrated on commercial polypropylene separator by tape casting method and sandwiched between a sulfur cathode and the separator as a shuttle inhibitor of the Li-S battery. The issues of lithium polysulfides dissolution and shuttle effect are inhibited distinctly, and significant improvements not only in the active material utilization but also in capacity retention are observed. What's more, the improvement mechanism is studied in detail. The results demonstrate that the sulfur and polysulfide species in separator and electrolyte for the cell with GO-coating separator are much less than that with the pristine separator. The GO membrane still maintains three-dimensional porous and flexible structure with a few lithium polysulfides and Li2S2/Li2S nanoparticles anchored on the surface and inter-layers of GO sheets after long cycles. And the active materials are significantly localized within the cathode structure after GO-coating. In addition, less sulfate species, lithium salts, polysulfides and other insoluble species are identified on the cathode and separator after long-term cycling.

  2. A look inside 'black box' hydrograph separation models: A study at the hydrohill catchment

    USGS Publications Warehouse

    Kendall, C.; McDonnell, Jeffery J.; Gu, W.

    2001-01-01

    Runoff sources and dominant flowpaths are still poorly understood in most catchments; consequently, most hydrograph separations are essentially 'black box' models where only external information is used. The well-instrumented 490 m2 Hydrohill artificial grassland catchment located near Nanjing (China) was used to examine internal catchment processes. Since groundwater levels never reach the soil surface at this site, two physically distinct flowpaths can unambiguously be defined: surface and subsurface runoff. This study combines hydrometric, isotopic and geochemical approaches to investigating the relations between the chloride, silica, and oxygen isotopic compositions of subsurface waters and rainfall. During a 120 mm storm over a 24 h period in 1989, 55% of event water input infiltrated and added to soil water storage; the remainder ran off as infiltration-excess overland flow. Only about 3-5% of the pre-event water was displaced out of the catchment by in-storm rainfall. About 80% of the total flow was quickflow, and 10% of the total flow was pre-event water, mostly derived from saturated flow from deeper soils. Rain water with high ??18O values from the beginning of the storm appeared to be preferentially stored in shallow soils. Groundwater at the end of the storm shows a wide range of isotopic and chemical compositions, primarily reflecting the heterogeneous distribution of the new and mixed pore waters. High chloride and silica concentrations in quickflow runoff derived from event water indicate that these species are not suitable conservative tracers of either water sources or flowpaths in this catchment. Determining the proportion of event water alone does not constrain the possible hydrologic mechanisms sufficiently to distinguish subsurface and surface flowpaths uniquely, even in this highly controlled artificial catchment. We reconcile these findings with a perceptual model of stormflow sources and flowpaths that explicitly accounts for water, isotopic

  3. Pervaporation separation of binary organic-aqueous liquid mixtures using crosslinked PVA membranes. I. Characterization of the reaction between PVA and PAA

    SciTech Connect

    Jiwon Rhim; Kewho Lee . Membranes and Separation Lab.); Minyoung Sohn; Hyeokjong Joo . Dept. of Polymer Science and Engineering)

    1993-10-20

    For the purpose of the water-selective membrane material development for pervaporation separation, poly(vinyl alcohol) (PVA) was crosslinked with a low molecular weight of poly(acrylic acid) (PAA). The crosslinking reactions between PVA and PAA were characterized through IR spectroscopy, differential scanning calorimetry (DSC), and tensile tests when varying the reaction conditions, that is, time, temperature, amounts of cross-linking agents, PAA. It was found that the crosslinking reaction was fast: in other words, that the reaction mainly occurred at the initial step of each reaction condition. The best reaction conditions for preparing the crosslinked PVA membranes were found to be: reaction time not over 1 h, reaction temperature in the range of 150-180 C. PAA contents of 15-20 wt% were found satisfactory with respect to the application areas.

  4. Study and Analysis of Heat Transfer Limitation of Separated Heat Pipe

    NASA Astrophysics Data System (ADS)

    Mou, Qizheng; Mou, Kai

    2002-01-01

    satellite and spacecraft. evaporator, heat isolation and condenser along the axial direction. The working fluid absorbs heat and evaporates in evaporator, and then the vapor flows to condenser and gives out heat. The condensed liquid is pumped to evaporator by wick. By the circulation, the heat can by transferred continuously. heat pipe as follow: - Vapor-liquid two phase flow inside pipe; - The manner of latent heat to transfer heat; - Automatic circulation by working fluid flowing - A certain extent of vacuum. and the traditional heat pipe, that is, the vapor fluid and liquid fluid flow along the same direction. So it is obviously that the separated heat pipe has special internal heat transfer characteristic and crisis. This paper has regard for the heat transfer crisis of the separated heat pipe, and meanwhile relevant calculation and analysis have been done. 1. FLOW TYPE OF THE WORKING FLUID IN SEPARATED HEAT PIPE 2. HEAT TRANSFER CRISIS IN THE EVAPORATOR 3. CARRYING PHENOMENON INSIDE SEPARATED HEAT PIPE 4. THE STAGNANT FLOW PHENOMENON AND THE BACKWARD FLOW PHENOMENON IN EVAPORATOR CONCLUSION transfer limitation of location burn-out, and the heat transfer limitation of flow unconventionality in erective pipe. The carrying phenomenon can occurs not only in evaporator but also in condenser of separated heat pipe. It is in the evaporator that should take place the heat transfer limitation of liquid film dry-out at first. Then with the increasing of heat flux, the heat transfer limitation of location burn-out would happen. In order to avoid the heat transfer limitation of flow unconventionality in erective pipe, the length and diameter of the outflow tube and inflow tube must be reasonably calculated to control the flow velocity of the working fluid inside pipe. Key words:Separated Heat PipeHeat Transfer LimitationDry-OutCarryingStagnancy

  5. Study on the hydrocyclonic separation of waste plastics with different density.

    PubMed

    Yuan, H; Fu, S; Tan, W; He, J; Wu, K

    2015-11-01

    The recycling of waste plastics is an important aspect in the recycling of solid waste. Based on the difference in density, PET and PVC particles was separated with help of the centrifugal sedimentation and shearing dispersion in a hydrocyclone. Through tests and CFD simulation, the relationship between the separating efficiency and pressure drop and split ratio has been investigated. Test results show that the Newton efficiency can reach above 80%, i.e. the purity of PVC could reach 93.2% while the purity of PET could reach 94.5%.

  6. Study on the separation performance of the multi-channel reduced graphene oxide membranes

    NASA Astrophysics Data System (ADS)

    Zhao, Yongjiao; Li, Chun; Fan, Xiaoyan; Wang, Jiesheng; Yuan, Guang; Song, Xinxiang; Chen, Jing; Li, Zhangde

    2016-10-01

    The multi-channel reduced graphene oxide membranes with separation function have been synthesized by a simple hydrothermal reduction method and vacuum filtration. In the as-synthesized membranes, the size, number, and type of the nanochannels can be controlled by the reduced temperature. The flux and retention rate of solution are investigated by filtering different size dye molecules. The interception and adsorption effect in the separation process are discussed. Furthermore, the sizes of the nanochannels in the membranes prepared by the different reduced temperatures are estimated. The results indicate that the multi-channel reduced graphene oxide membranes have potential application in water purification area.

  7. Theoretical study of the 2A2-2B2 separation of the alkali superoxides

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Sodupe, Mariona; Partridge, Harry; Langhoff, Stephen R.

    1992-01-01

    The computed 2A2-2B2 separations of the alkali superoxides are in good agreement with those deduced from electron-spin resonance spectra. The calculations definitively show that the ground state of CsO2 is 2A2. The larger than expected separation for CsO2, based on the trend from LiO2 to RbO2, is attributed primarily to the differential effects of core relaxation. The CsO2 dissociation energy is computed to be 42.7 kcal/mol, with an uncertainty conservatively estimated as +/- 4 kcal/mol.

  8. A Case Study of Institutional Divorce: The Separation of a Community College From a University. ASHE Annual Meeting Paper.

    ERIC Educational Resources Information Center

    Cooper, Joanne

    This case study examined the separation of a community college from a local university where both had functioned as one for 20 years. The study used Robert Yin's model of investigating a "real-life" situation and several sources of data including: informal interviews, field notes, and archival data. In addition, the metaphor of…

  9. Cognitive-Behavioral Therapy with a Six-Year-Old Boy with Separation Anxiety Disorder: A Case Study.

    ERIC Educational Resources Information Center

    Dia, David A.

    2001-01-01

    This study examines the use of cognitive-behavioral therapy (CBT) for the treatment of separation anxiety disorder (SAD) in a six-year-old boy who was having at least one panic attack a day. It uses a four-phased program that includes a psychoeducational approach. The outcome studies demonstrated how CBT shows promise as a treatment modality with…

  10. Effects of mercury on spermatogenesis studied by velocity sedimentation cell separation and serial mating.

    PubMed

    Lee, I P; Dixon, R L

    1975-07-01

    Recently the potential toxicity of environmental mercury has become a major concern. Human tissues contain mercury due to daily environmental exposure. Nearly all of the mercury contaminating food is in the form of methylmercury complexes, due to the biotransformation of inorganic mercury. This report compares the reproductive effects of methylmercury hydroxide and mercuric chloride in male mice. The mercuric compounds were administered intraperitoneally once at a dose of 1 mg/kg (based on Hg++ concentration), or spermatogenic cells were exposed in vitro to Hg+ concentrations ranging from 10(-3) to 10(-8)M. Spermatogenic cells were separated for biochemical studies using the velocity sedimentation technique, and in vivo serial mating was used to assess fertility. The effects of CH3Hg+ or Hg++ on the uptake of 3H-thymidine by spermatogonia, 3H-uridine by early elongated spermatids, and 3H-L-leucine by late elongated spermatids were studied. These in vitro experiments indicated that at 1-(-3) m CH2HgOH reduced thymidine incorporation by spermatogonia by 40%, uridine incorporation by elongated spermatids by 39% and L-leucine incorporation by late elongated spermatids by 40%. Results obtained with HgCl2 were similar but of lesser magnitude. In vivo administration of CH3HgOH and HgCl2 significantly inhibited the uptake of thymidine, uridine and L-leucine by their respective spermatogenic cells. Fertility profiles obtained from serial mating studies indicated that the primary effect of CH3HgOH was on spermatogonial cells, premeiotic spermatocytes and early elongated spermatids, with no apparent effect on spermatozoa in testis, peididymis or vas deferentia. HgCl2 also primarily affected spermatogonial and premeiotic cells, but the effect was less than that seen with CH3HgOH. Statistical analysis indicated significant antifertility effects. Inhibition of uptake of thymidine and uridine was well correlated with the functionality of these cells as reflected in the fertility

  11. Separation of small metabolites and lipids in spectra from biopsies by diffusion-weighted HR-MAS NMR: a feasibility study.

    PubMed

    Diserens, G; Vermathen, M; Precht, C; Broskey, N T; Boesch, C; Amati, F; Dufour, J-F; Vermathen, P

    2015-01-07

    High Resolution Magic Angle Spinning (HR-MAS) NMR allows metabolic characterization of biopsies. HR-MAS spectra from tissues of most organs show strong lipid contributions that are overlapping metabolite regions, which hamper metabolite estimation. Metabolite quantification and analysis would benefit from a separation of lipids and small metabolites. Generally, a relaxation filter is used to reduce lipid contributions. However, the strong relaxation filter required to eliminate most of the lipids also reduces the signals for small metabolites. The aim of our study was therefore to investigate different diffusion editing techniques in order to employ diffusion differences for separating lipid and small metabolite contributions in the spectra from different organs for unbiased metabonomic analysis. Thus, 1D and 2D diffusion measurements were performed, and pure lipid spectra that were obtained at strong diffusion weighting (DW) were subtracted from those obtained at low DW, which include both small metabolites and lipids. This subtraction yielded almost lipid free small metabolite spectra from muscle tissue. Further improved separation was obtained by combining a 1D diffusion sequence with a T2-filter, with the subtraction method eliminating residual lipids from the spectra. Similar results obtained for biopsies of different organs suggest that this method is applicable in various tissue types. The elimination of lipids from HR-MAS spectra and the resulting less biased assessment of small metabolites have potential to remove ambiguities in the interpretation of metabonomic results. This is demonstrated in a reproducibility study on biopsies from human muscle.

  12. Study of the separation limits of continuous solid support free liquid-liquid chromatography: separation of capsaicin and dihydrocapsaicin by centrifugal partition chromatography.

    PubMed

    Goll, Johannes; Frey, Andreas; Minceva, Mirjana

    2013-04-05

    Sequential centrifugal partition chromatography (sCPC) is a cyclic solid support-free liquid-liquid chromatographic process, in which a continuously introduced feed mixture is separated into two sequentially collected product streams. The few experimental demonstrations of this concept already revealed its potential for the preparative separation of pharmaceuticals and fine chemicals. In this work not only the possibilities, but also the limits of the sCPC technology are explored. A feed mixture consisting of capsaicin and dihydrocapsaicin, whose molecular structure differs in only one double bond, was selected for this purpose. The sCPC unit operating parameters needed for a complete separation of the feed mixture were selected using the recently published approach, which uses the partition coefficient of the feed components and the hydrodynamic characteristics of the system as input data. A complete separation of capsaicin and dihydrocapsaicin with the solvent system heptane/ethyl acetate/methanol/water:1/1/1/1 (v/v/v/v) was achieved, although the separation factor was only 1.32. The sCPC unit separation performance was successfully simulated using the cell model.

  13. A Study of Pulsed Blowing Effect on Flow Separation over Flap

    NASA Astrophysics Data System (ADS)

    Wang, Yankui; Zhou, Ping; Li, Qian

    2015-11-01

    With the development of the modern aircraft, such as tailless flying configuration, traditional flaps are also the main control surfaces for flight controlling. However, the efficiency of the flap is not only descent quickly due to flow separation over itself under higher deflection angle of flap, but also is evidently influenced by the flow coming down from the upstream wing. A novel flow control technique to improve the flow separation over the flap by pulsed blowing is investigated in this paper by wind tunnel test under Reynolds number of 0.6* 10E6 2.4* 10E6. To begin with, the control performance for flow separation over the flap is very sensitive to the blowing position and direction and the flow separation can be recovered by the pulsed blowing evidently. Secondly, the pulsed blowing efficiency is 30% higher than that of continuous blowing with the same consumption. In addition, the pulsed blowing efficiency increases quickly with the increasing of pulsed blowing frequency and keep constant gradually when the pulsed blowing Stroul number is bigger than 0.6. National Natural Science Foundation of China (11272035).

  14. Studies of hadron-electron separators for the ZEUS barrel calorimeter

    SciTech Connect

    Ambats, I.; Bortz, D.; Connolly, A.

    1995-05-25

    Two possible upgrades, a shower maximum detector and a presampler, designed to improve the low energy electron/hadron separation capabilities of the ZEUS barrel calorimeter are described and test-beam results are reported. The presampler can also be used to correct for energy loss of particles traversing the dead material in front of the calorimeter.

  15. The Dynamics of Integration and Separation: ERP, MEG, and Neural Network Studies of Immediate Repetition Effects

    ERIC Educational Resources Information Center

    Huber, David E.; Tian, Xing; Curran, Tim; O'Reilly, Randall C.; Woroch, Brion

    2008-01-01

    This article presents data and theory concerning the fundamental question of how the brain achieves a balance between integrating and separating perceptual information over time. This theory was tested in the domain of word reading by examining brain responses to briefly presented words that were either new or immediate repetitions. Critically,…

  16. Fundamental Studies of Subsonic and Transonic Flow Separation. Part I. First Phase Summary Report

    DTIC Science & Technology

    1975-09-01

    Tullahoma, Tennessee, Nov. 26~30, 1973. 46 AEDC·TR-75-95 21. Dudziniski I Thomas J. and Krause, Lloyd N., "Effect of Inlet Geometry on Flow Angle...Stratford, B. S., "The Prediction of Separation of the Turbulent Boundary Layer," J. Fluid Mech. 5, 1958. 25. Nash, J. F., QUincey , V. G and Callinan, J

  17. Phase separation of polymer mixtures induced by light and heat: a comparative study by light scattering

    NASA Astrophysics Data System (ADS)

    Ochi, Yuki; Kawakubo, Rie; Van-Pham, Dan-Thuy; Kitamura, Yuki; Nakanishi, Hideyuki; Norisuye, Tomohisa; Tran-Cong-Miyata, Qui

    2015-12-01

    Phase separation of binary blends composed of a polystyrene derivative (PS) and poly (vinyl methyl ether) (PVME) with a lower critical solution temperature (LCST) was experimentally induced by two different methods: heating and UV light irradiation. Using laser light scattering combined with the temperature jump (T-jump) technique, it was demonstrated that in the case of heating, the mixture undergoes phase separation via the nucleation-and-growth (NG) and the spinodal decomposition (SN) processes under shallow and deep quenches, respectively. Particularly, the crossover from the spinodal decomposition to the nucleation-and-growth process was observed at long time under a deep T-jump by light-scattering experiments. On the other hand, in the photo-crosslink case, the PS/PVME blends undergo a nucleation-and-growth process upon irradiation with weak light intensity, whereas the mixture exhibits the spinodal decomposition under irradiation with strong light intensity. From the analysis of the light-scattering data obtained for the blends under the photo-crosslink, the kinetic data reveal the suppression of morphologies having large characteristic length scales. This feature clearly differs from the phase separation induced by heating where no mode-suppression process was observed. It was also found that distribution of the characteristic length scales (the regularity) of the morphology becomes narrow as the phase separation proceeds for reacting blends, whereas it becomes broader as the phase separation proceeds by heating, revealing the important roles of reaction in the suppression of fluctuations with long wavelengths. These experimental results establish a method to control the length scales and the regularity of the morphology of polymer blends by chemical reaction.

  18. Summary of synfuel characterization and combustion studies

    NASA Technical Reports Server (NTRS)

    Schultz, D. F.

    1983-01-01

    Combustion component research studies aimed at evolving environmentally acceptable approaches for burning coal derived fuels for ground power applications were performed at the NASA Lewis Research Center under a program titled the ""Critical Research and Support Technology Program'' (CRT). The work was funded by the Department of Energy and was performed in four tasks. This report summarizes these tasks which have all been previously reported. In addition some previously unreported data from Task 4 is also presented. The first, Task 1 consisted of a literature survey aimed at determining the properties of synthetic fuels. This was followed by a computer modeling effort, Task 2, to predict the exhaust emissions resulting from burning coal liquids by various combustion techniques such as lean and rich-lean combustion. The computer predictions were then compared to the results of a flame tube rig, Task 3, in which the fuel properties were varied to simulate coal liquids. Two actual SRC 2 coal liquids were tested in this flame tube task.

  19. SERDP munition disposal source characterization pilot study

    SciTech Connect

    McCallen, R.C.; Couch, R.G.; Fried, L.E.

    1995-09-01

    The Strategic Environmental Research and Development Program (SERDP) is supporting studies to develop and implement technologies for the safe, efficient, and environmentally sound disposal of obsolete munitions and propellants which are stored at various locations across the country. One proposed disposal technique is the open-air burning or detonation (OB/OD) of this material. Although OB/OD is viewed as an efficient and cost-effective method for reducing the inventory of unwanted munitions and propellants, questions regarding its safety and environmental impacts must be addressed. Since very large amounts of munitions and propellants must be consumed inexpensively in relatively short time periods and with the very restrictive Federal and State regulations on environmental issues, it is clear that traditional OB/OD procedures will not be acceptable and that it is necessary to develop modified or advanced OB/OD technology. The effectiveness and environmental impact of the OB/OD technology must be verified by experimental data and with validated numerical models for acceptance by Federal and State regulators. Specifically, technology must be developed and tested that minimizes toxic bum and detonation products the noise (peak pressure) and destructive effect (impulse) of the explosive blast generation and travel distance of shrapnel, and entrainment of dust. Three explosion attenuation scenarios are analyzed: Contained water, aqueous foams, and wet sand.

  20. Characterization of separability and entanglement in (2xD)- and (3xD)-dimensional systems by single-qubit and single-qutrit unitary transformations

    SciTech Connect

    Giampaolo, Salvatore M.; Illuminati, Fabrizio

    2007-10-15

    We investigate the geometric characterization of pure state bipartite entanglement of (2xD)- and (3xD)-dimensional composite quantum systems. To this aim, we analyze the relationship between states and their images under the action of particular classes of local unitary operations. We find that invariance of states under the action of single-qubit and single-qutrit transformations is a necessary and sufficient condition for separability. We demonstrate that in the (2xD)-dimensional case the von Neumann entropy of entanglement is a monotonic function of the minimum squared Euclidean distance between states and their images over the set of single qubit unitary transformations. Moreover, both in the (2xD)- and in the (3xD)-dimensional cases the minimum squared Euclidean distance exactly coincides with the linear entropy [and thus as well with the tangle measure of entanglement in the (2xD)-dimensional case]. These results provide a geometric characterization of entanglement measures originally established in informational frameworks. Consequences and applications of the formalism to quantum critical phenomena in spin systems are discussed.

  1. Ionene membrane battery separator

    NASA Technical Reports Server (NTRS)

    Moacanin, J.; Tom, H. Y.

    1969-01-01

    Ionic transport characteristics of ionenes, insoluble membranes from soluble polyelectrolyte compositions, are studied for possible application in a battery separator. Effectiveness of the thin film of separator membrane essentially determines battery lifetime.

  2. Fabrication and characterization of superhydrophobic copper fiber sintered felt with a 3D space network structure and their oil-water separation

    NASA Astrophysics Data System (ADS)

    Hu, Jinyi; Yuan, Wei; Chen, Wenjun; Xu, Xiaotian; Tang, Yong

    2016-12-01

    This study reports the fabrication of a novel stable superhydrophobic and superoleophylic porous metal material on a copper fiber sintered felt (CFSF) substrate via a simple solution-immersion method. Oxidation and modification times are two important factors related to the level of hydrophobicity; oxidation for 1 h and modification for 24 h are appropriate to build a superhydrophobic CFSF surface with a water contact angle of 152.83° and a kerosene contact angle of 0°. The stability and high temperature resistance of superhydrophobic CFSF were studied. A novel device was designed to measure the water repellent ability of the treated CFSF. The results indicated that the water repellent ability of superhydrophobic CFSF was almost constant after 40 cycles of sanding. Both the water contact angle and the microstructure of the modified CFSF surface remained nearly unchanged after experiencing ultrasonic vibration for 1 min. The modified CFSF surface maintains super hydrophobicity after being treated at 180 °C for 1 h. The separation efficiencies for different types of oils and organic solvents (kerosene, chloroform, n-hexane and gasoline) are more than 96%. The modified CFSF retains a high robustness of separation efficiency even after it is recycled for the separation of kerosene and water for more than 10 times.

  3. A Computational Study on the Effects of Dynamic Roughness Application to Separated Transitional Flows Affected by Adverse Pressure Gradient

    NASA Astrophysics Data System (ADS)

    Campitelli, Gennaro

    The study of transitional flows is considered crucial for many practical engineering applications. In fact, a comprehensive understanding of the laminar-turbulent transition phenomenon often helps to improve the overall performance of apparatuses such as airfoils, wind turbines, hulls and turbomachinery blades. In addition to understanding and prediction of transitional flows, active research continues in the area of boundary layer control, which includes control of phenomena such as flow separation and transition. For instance, optimum geometrical shaping may be followed by the adoption on the wall-surface of riblets to adjust pressure gradient and reduce drag. Further "flow control" may also be acquired by introducing active devices able to modify the flow field in order to accomplish a desired aerodynamic task. Such flow manipulation is often achieved by using time-dependent forcing mechanisms which promote natural instabilities amplifying the control effectiveness. Localized energy inputs such as Lorentz-force actuator, piezoelectric flaps and synthetic jets all produce a consistent boundary layer mixing enhancement with lift increase and drag abatement. The current numerical study attempts to demonstrate the efficacy of dynamic roughness (DR) on altering separated-reattached transitional flows under adverse pressure gradient. It has already been proven how DR, acting on the boundary sublayer perturbation, is able to suppress (partially or completely) the typical leading edge separation for an airfoil at different angles of attack. This makes DR particularly suitable for separated flow control applications where the shear layer reattaches presenting the characteristic laminar separation bubble. A numerical sensitivity study has been conducted with an efficient orthogonal design taking into account four different control parameters on three levels (actuation frequency, humps height, rows displacement, synchronization) to provide an optimum DR setup which limits

  4. Extraction and separation studies of platinum(IV) with N-n-octylaniline.

    PubMed

    Lokhande, T N; Anuse, M A; Chavan, M B

    1998-11-01

    N-n-octylaniline in xylene is used for the extractive separation of platinum(IV) from acidic media. Platinum(IV) was extracted quantitatively with 10 ml of 3% reagent in xylene from 0.5 to 10 and 2.5 to 10 M hydrochloric and sulphuric acid, respectively. It was stripped from organic phase with water and estimated photometrically with stannous chloride. The effect of metal ion, acids, reagent concentration and of various foreign ions has been investigated. The method affords binary separation of platinum(IV) from iron(III), cobalt(II), nickel(II) and copper(II), and is applicable to the analysis of synthetic mixtures and alloys. The method is fast, accurate and precise.

  5. 300-FF-1 operable unit remedial investigation phase II report: Physical separation of soils treatability study

    SciTech Connect

    Not Available

    1994-04-01

    This report describes the approach and results of physical separations treatability tests conducted at the Hanford Site in the North Process Pond of the 300-FF-1 Operable Unit. Physical separation of soils was identified as a remediation alternative due to the potential to significantly reduce the amount of contaminated soils prior to disposal. Tests were conducted using a system developed at Hanford consisting of modified EPA equipment integrated with screens, hoppers, conveyors, tanks, and pumps from the Hanford Site. The treatability tests discussed in this report consisted of four parts, in which an estimated 84 tons of soil was processed: (1) a pre-test run to set up the system and adjust system parameters for soils to be processed; (2) a baseline run to establish the performance of the system - Test No. 1; (3) a final run in which the system was modified as a result of findings from the baseline run - Test No. 2; and (4) water treatment.

  6. Studies on separation and purification of fission (99)Mo from neutron activated uranium aluminum alloy.

    PubMed

    Rao, Ankita; Kumar Sharma, Abhishek; Kumar, Pradeep; Charyulu, M M; Tomar, B S; Ramakumar, K L

    2014-07-01

    A new method has been developed for separation and purification of fission (99)Mo from neutron activated uranium-aluminum alloy. Alkali dissolution of the irradiated target (100mg) results in aluminum along with (99)Mo and a few fission products passing into solution, while most of the fission products, activation products and uranium remain undissolved. Subsequent purification steps involve precipitation of aluminum as Al(OH)3, iodine as AgI/AgIO3 and molybdenum as Mo-α-benzoin oxime. Ruthenium is separated by volatilization as RuO4 and final purification of (99)Mo was carried out using anion exchange method. The radiochemical yield of fission (99)Mo was found to be >80% and the purity of the product was in conformity with the international pharmacopoeia standards.

  7. A study on multi-body floating system in finite water depth by separate region method

    SciTech Connect

    Inoue, Yoshiyuki; Zhang, Xuangang

    1996-12-31

    The research on multi-body floating system has been carried out by many researchers in recent days because of its increased practical uses. In these researches, almost all, three-dimensional source method is applied. In this paper, a relatively simple but effective method, separated region method, is applied for predicting the responses of multi-floating bodies in finite water depth. For a floating rectangular section in the finite water depth, the separated region method (eigenvalue method) is very useful to predict the hydrodynamic forces on the body. The method has been extended here, so as to apply to the problems of multi-floating bodies. To check the validity of the method, motion responses of two floating bodies were calculated and the results were compared with experimental data carried out by M. Ohkusu (1976) and M. Kubo et al. (1989). The agreements between the theoretical and the experimental results of motions of two floating bodies are fairly good.

  8. The numerical study of energy separation in a two-cascade Leontiev tube

    NASA Astrophysics Data System (ADS)

    Makarov, M. S.; Makarova, S. N.; Shibaev, A. A.

    2016-10-01

    This paper presents results of numerical modeling of energy separation for helium- xenon gas mixture flow in a two-cascade Leontiev tube with central and outer (annular) supersonic nozzles. The Mach number and stagnation temperature distributions in longitudinal section and the heat-transfer intensity from the subsonic to supersonic flow have been obtained. The dependences of the cooling effect, the temperature efficiency factor and the adiabatic efficiency on a stagnation pressure in the receiver have been investigated.

  9. A Langevin dynamics study of mobile filler particles in phase-separating binary systems

    NASA Astrophysics Data System (ADS)

    Laradji, Mohamed

    2004-05-01

    The dynamics of phase separation in a simple binary mixture containing mobile filler particles that are preferentially wet by one of the two components is investigated systematically via Langevin simulations in two dimensions. We found that while the filler particles reduce the growth rate of spinodal decomposition, the domain growth remains essentially identical to that of the pure binary mixture. The growth rate diminishes as either the filler particles concentration is increased or their diffusivity is decreased.

  10. Study of Control Parameters for Separation Mitigation Using an Asymmetric Single Dielectric Barrier Plasma Actuator

    DTIC Science & Technology

    2006-01-01

    which results in the enhancement of near-wall momentum yielding a wall- jet feature that effectively eliminates the separation bubble. (Some figures...boundary layer attachment on airfoils 0963-0252/06/040735+09$30.00 © 2006 IOP Publishing Ltd Printed in the UK 735 Report Documentation Page Form...The momentum of the plasma couples to neutral gas through collisions, which results in the enhancement of near-wall momentum yielding a wall- jet

  11. Charge separation and transport in conjugated-polymer/semiconductor-nanocrystal composites studied by photoluminescence quenching and photoconductivity

    SciTech Connect

    Greenham, N.C.; Peng, X.; Alivisatos, A.P.

    1996-12-01

    We study the processes of charge separation and transport in composite materials formed by mixing cadmium selenide or cadmium sulfide nanocrystals with the conjugated polymer poly(2-methoxy,5-(2{prime}-ethyl)-hexyloxy-{ital p}-phenylenevinylene) (MEH-PPV). When the surface of the nanocrystals is treated so as to remove the surface ligand, we find that the polymer photoluminescence is quenched, consistent with rapid charge separation at the polymer/nanocrystal interface. Transmission electron microscopy of these quantum-dot/conjugated-polymer composites shows clear evidence for phase segregation with length scales in the range 10{endash}200 nm, providing a large area of interface for charge separation to occur. Thin-film photovoltaic devices using the composite materials show quantum efficiencies that are significantly improved over those for pure polymer devices, consistent with improved charge separation. At high concentrations of nanocrystals, where both the nanocrystal and polymer components provide continuous pathways to the electrodes, we find quantum efficiencies of up to 12{percent}. We describe a simple model to explain the recombination in these devices, and show how the absorption, charge separation, and transport properties of the composites can be controlled by changing the size, material, and surface ligands of the nanocrystals. {copyright} {ital 1996 The American Physical Society.}

  12. A study and extension of second-order blind source separation to operational modal analysis

    NASA Astrophysics Data System (ADS)

    Antoni, J.; Chauhan, S.

    2013-02-01

    Second-order blind source separation (SOBSS) has gained recent interest in operational modal analysis (OMA), since it is able to separate a set of system responses into modal coordinates from which the system poles can be extracted by single-degree-of-freedom techniques. In addition, SOBSS returns a mixing matrix whose columns are the estimates of the system mode shapes. The objective of this paper is threefold. First, a theoretical analysis of current SOBSS methods is conducted within the OMA framework and its precise conditions of applicability are established. Second, a new separation method is proposed that fixes current limitations of SOBSS: It returns estimate of complex mode shapes, it can deal with more active modes than the number of available sensors, and it shows superior performance in the case of heavily damped and/or strongly coupled modes. Third, a theoretical connection is drawn between SOBSS and stochastic subspace identification (SSI), which stands as one of the points of reference in OMA. All approaches are finally compared by means of numerical simulations.

  13. Droplet activation, separation, and compositional analysis: Laboratory studies and atmospheric measurements

    SciTech Connect

    Hiranuma, Naruki; Kohn, Monika; Pekour, Mikhail S.; Nelson, Danny A.; Shilling, John E.; Cziczo, Daniel J.

    2011-01-24

    Droplets produced in a cloud condensation nucleus chamber as a function of supersaturation have been separated from unactivated aerosol particles using counterflow virtual impaction. Residual material after droplets were evaporated was chemically analyzed with an Aerodyne Aerosol Mass Spectrometer and the Particle Analysis by Laser Mass Spectrometry instrument. Experiments were initially conducted to verify activation conditions for monodisperse ammonium sulfate particles and to determine the resulting droplet size distribution as a function of supersaturation. Based on the observed droplet size, the counterflow virtual impactor cut-size was set to differentiate droplets from unactivated interstitial particles. Validation experiments were then performed to verify that only droplets with sufficient size passed through the counterflow virtual impactor for subsequent analysis. A two-component external mixture of monodisperse particles was also exposed to a supersaturation which would activate one of the types (ammonium sulfate) but not the other (polystyrene latex spheres). The mass spectrum observed after separation indicated only the former, validating separation of droplets from unactivated particles. Results from atmospheric measurements using this technique indicate that aerosol particles often activate predominantly as a function of particle size. Chemical composition is not irrelevant, however, and we observed enhancement of sulfate in droplet residuals using single particle analysis.

  14. Droplet activation, separation, and compositional analysis: laboratory studies and atmospheric measurements

    NASA Astrophysics Data System (ADS)

    Hiranuma, N.; Kohn, M.; Pekour, M. S.; Nelson, D. A.; Shilling, J. E.; Cziczo, D. J.

    2011-10-01

    Droplets produced in a cloud condensation nuclei chamber (CCNC) as a function of supersaturation have been separated from unactivated aerosol particles using counterflow virtual impaction. Residual material after droplets were evaporated was chemically analyzed with an Aerodyne Aerosol Mass Spectrometer (AMS) and the Particle Analysis by Laser Mass Spectrometry (PALMS) instrument. Experiments were initially conducted to verify activation conditions for monodisperse ammonium sulfate particles and to determine the resulting droplet size distribution as a function of supersaturation. Based on the observed droplet size, the counterflow virtual impactor cut-size was set to differentiate droplets from unactivated interstitial particles. Validation experiments were then performed to verify that only droplets with sufficient size passed through the counterflow virtual impactor for subsequent analysis. A two-component external mixture of monodisperse particles was also exposed to a supersaturation which would activate one of the types (hygroscopic salts) but not the other (polystyrene latex spheres or adipic acid). The mass spectrum observed after separation indicated only the former, validating separation of droplets from unactivated particles. Results from ambient measurements using this technique and AMS analysis were inconclusive, showing little chemical differentiation between ambient aerosol and activated droplet residuals, largely due to low signal levels. When employing as single particle mass spectrometer for compositional analysis, however, we observed enhancement of sulfate in droplet residuals.

  15. Droplet activation, separation, and compositional analysis: laboratory studies and atmospheric measurements

    NASA Astrophysics Data System (ADS)

    Hiranuma, N.; Kohn, M.; Pekour, M. S.; Nelson, D. A.; Shilling, J. E.; Cziczo, D. J.

    2011-01-01

    Droplets produced in a cloud condensation nucleus chamber as a function of supersaturation have been separated from unactivated aerosol particles using counterflow virtual impaction. Residual material after droplets were evaporated was chemically analyzed with an Aerodyne Aerosol Mass Spectrometer and the Particle Analysis by Laser Mass Spectrometry instrument. Experiments were initially conducted to verify activation conditions for monodisperse ammonium sulfate particles and to determine the resulting droplet size distribution as a function of supersaturation. Based on the observed droplet size, the counterflow virtual impactor cut-size was set to differentiate droplets from unactivated interstitial particles. Validation experiments were then performed to verify that only droplets with sufficient size passed through the counterflow virtual impactor for subsequent analysis. A two-component external mixture of monodisperse particles was also exposed to a supersaturation which would activate one of the types (ammonium sulfate) but not the other (polystyrene latex spheres). The mass spectrum observed after separation indicated only the former, validating separation of droplets from unactivated particles. Results from atmospheric measurements using this technique indicate that aerosol particles often activate predominantly as a function of particle size. Chemical composition is not irrelevant, however, and we observed enhancement of sulfate in droplet residuals using single particle analysis.

  16. Comparative study of hybrid RANS-LES models for separated flows

    NASA Astrophysics Data System (ADS)

    Kumar, G.; Lakshmanan, S. K.; Gopalan, H.; De, A.

    2016-06-01

    Hybrid RANS-LES models are proven to be capable of predicting massively separated flows with reasonable computation cost. In this paper, Spalart-Allmaras (S-A) based detached eddy simulation (DES) model and three SST based hybrid models with different RANS to LES switching criteriaare investigated. The flow over periodic hill at Re = 10,595 is chosen as the benchmark for comparing the performance of the different models due to the complex flow physics and reasonablecomputational cost. The model performances are evaluated based on their prediction capabilities of velocity and stress profiles, and separation and reattachment point. The simulated results are validatedagainst experimental and numerical results available in literature. The S-A DES model predicted separation bubble accurately at the top of the hill, as reported earlier in experiments and other numerical results. This model also correctly predicted velocity and stress profiles in recirculation region. However, the performance of this model was poor in the post reattachment region. On the other hand, the k-ω SST based hybrid models performed poorly in recirculation region, but it fairly predicted stress profiles in post reattachment region.

  17. [Experimental study on methane potentials of source-separated BMW and individual waste materials].

    PubMed

    Feng, Lei; Li, Run-dong; Li, Yan-ji; Ke, Xin; Wei, Li-hong; Luo, Xiao-song

    2008-08-01

    A laboratory procedure is described for measuring methane potentials of source-separated bio-organic municipal waste (BMW). Triplicate reactors with about 20 grams fresh material were incubated at 37 degrees C with 300 mL inoculum from Shenyang wastewater treatment plant and the methane production was followed over a 50 d period by regular measurement of methane on a gas chromatograph. At 37 degrees C, the methane production efficiency of source-separated BMW and individual waste materials was: starch > BMW > protein > food oil > fat > paper. For the source-separated BMW,starch,protein,food oil,fat and paper, the methane potential (CH4/VS) of 218.15, 209.11, 194.20, 238.86, 257.82 and 131.41 mL/g were found,and ultimate biodegradability of 6 difference materials were 67.73%, 72.88%, 65.84%, 78.38%, 74.11% and 47.98%, respectively.

  18. Parent-Child Interaction Therapy for Treatment of Separation Anxiety Disorder in Young Children: A Pilot Study

    ERIC Educational Resources Information Center

    Choate, Molly L.; Pincus, Donna B.; Eyberg, Sheila M.; Barlow, David H.

    2005-01-01

    Research suggests that Parent-Child Interaction therapy (PCIT) works to improve the child's behavior by changing the child-parent interaction. PCIT has been effective in treating disruptive behavior in young children. This article describes a pilot study to apply PCIT to the treatment of separation anxiety disorder (SAD). A multiple-baseline…

  19. Pressure influence on the structural characteristics of modified absorptive glass mat separators: A standard contact porosimetry study

    NASA Astrophysics Data System (ADS)

    Burashnikova, M. M.; Khramkova, T. S.; Kazarinov, I. A.; Shmakov, S. L.

    2015-09-01

    The article presents a comparative analysis of the structural characteristics of absorptive glass mats manufactured by "Hollingsworth & Vose" (a 2.8 mm thickness) and "Bernard Dumas" (a 3.0 mm thickness) modified by impregnation with polymeric emulsions based on polyvinylidene fluoride, a polyvinylpyrrolidone styrene copolymer, and polytetrafluoroethylene, by means of standard contact porosimetry. The key study is influence of features of the porous structure on the compression properties, the rate of wicking, and the oxygen cycle efficiency in lead-acid battery mock-ups under several plate-group compression pressures. It is found that the treatment of the absorptive glass mat separators with polymeric emulsions leads to redistribution of their pores by size. An increased pressure in the electrode unit insignificantly changes the pore structure of the modified absorptive glass mat separators, and the oxygen cycle efficiency rises in comparison with unmodified separators.

  20. Evaluation and Characterization of Membranes for HI/H2O/I2 Water Separation for the S-I Cycle

    SciTech Connect

    Frederick F. Stewart

    2005-09-01

    In the Sulfur-Iodine (S-I) thermochemical cycle, iodine is added to the product of the Bunsen reaction to facilitate the separation of sulfuric acid (H2SO4) from hydriodic acid (HI). The amount of iodine can be as high as 83% of the overall mass load of the Bunsen product stream, which potentially introduces a large burden on the cycle’s efficiency. Removal of water from the HI and I2 mixture would substantially reduce the amount of required additional iodine. In this work, Nafion® membranes have been studied for their use as de-watering membranes. Specifically, two thicknesses of Nafion membranes have been found to be effective in this application. The thicker membrane, Nafion-117®, produces moderate fluxes of water with very high separation factors. On the other hand, the thinner membrane, Nafion-112®, yielded very large fluxes of water, however with smaller separation factors. All membranes were found to be durable and did not degrade in contact with the feed stream over periods of time up to three months.

  1. A fine coal circuitry study using column flotation and gravity separation. Quarterly report, 1 March 1995--31 May 1995

    SciTech Connect

    Honaker, R.Q.; Reed, S.

    1995-12-31

    Column flotation provides excellent recovery of ultrafine coal while producing low ash content concentrates. However, column flotation is not efficient for treating fine coal containing significant amounts of mixed-phase particles. Fortunately, enhanced gravity separation has proved to have the ability to treat the mixed-phased particles more effectively. A disadvantage of gravity separation is that ultrafine clay particles are not easily rejected. Thus, a combination of these two technologies may provide a circuit that maximizes both the ash and sulfur rejection that can be achieved by physical coal cleaning while maintaining a high energy recovery. This project is studying the potential of using different combinations of gravity separators, i.e., a Floatex hydrosizer and a Falcon Concentrator, and a proven flotation column, which will be selected based on previous studies by the principle investigator. During this reporting period, an extensive separation performance comparison between a pilot-scale Floatex Density Separator (18{times}18-inch) and an existing spiral circuit has been conducted at Kerf-McGee Coal Preparation plan for the treatment of nominally {minus}16 mesh coal. The results indicate that the Floatex is a more efficient separation device (E{sub p}=0.12) than a conventional coal spiral (E{sub p}=0.18) for Illinois seam coals. In addition, the treatment of {minus}100 mesh Illinois No. 5 fine coal from the same plant using Falcon concentrator, column flotation (Packed-Column) and their different combinations was also evaluated. For a single operation, both Falcon concentrator and column flotation can produce a clean coal product with 90% combustible recovery and 5% ash content. In the case of the combined circuit, column flotation followed by the Falcon achieved a higher combustible recovery value (about 75%) than that obtained by the individual units while maintaining an ash content less than 3%.

  2. A study of the microstructure-property relationship for MFI-type zeolite membranes for xylene separation

    NASA Astrophysics Data System (ADS)

    O'Brien, Jessica

    Effective separation of xylene isomers is possible through continuous membrane processes, specifically pervaporation, utilizing MFI-type zeolite membranes. The average pore size of MFI-type zeolite (0.6 nanometers) is large enough to allow para-xylene (molecular size ˜0.56 nanometers) to pass and excludes bulkier ortho- and meta-isomers (molecular size ˜0.68 nanometers). Separation through MFI-type zeolite occurs via transport differences of each isomer across the membrane and it is desired to exploit this property for use in pervaporation. Currently, MFI-type membranes have demonstrated the ability to separate xylene isomers under vapor permeation conditions where the partial pressures of xylene are extremely low resulting in impractically low flux values; at increased xylene exposure the separation capability is lost. The objective of this dissertation is to present a fundamental study on the transport of xylene isomers through MFI-type zeolite membranes of varying microstructure in an effort address this problem. There are three fundamental areas which are covered: (1) the relationship between synthesis, microstructure, quality, and separation performance of xylene isomers, (2) determination of how the adsorption properties of the xylene-MFI system (specifically adsorbate-zeolite and adsorbate-adsorbate interactions) affect separation capability, and (3) how to tailor the MFI type zeolite membranes for optimum performance in terms of para-xylene selectivity, flux and stability when operating under pervaporation conditions. Observation of the differences in transport and separation capability through MFI membranes of varying microstructure and defect concentrations show these properties can significantly affect membrane performance as well as mechanical stability. Fundamental studies demonstrate that the framework distortion experienced by the MFI zeolite at high para-xylene loading results in the loss of molecular sieving capability and is the cause of poor

  3. Chiral Separations

    NASA Astrophysics Data System (ADS)

    Stalcup, A. M.

    2010-07-01

    The main goal of this review is to provide a brief overview of chiral separations to researchers who are versed in the area of analytical separations but unfamiliar with chiral separations. To researchers who are not familiar with this area, there is currently a bewildering array of commercially available chiral columns, chiral derivatizing reagents, and chiral selectors for approaches that span the range of analytical separation platforms (e.g., high-performance liquid chromatography, gas chromatography, supercritical-fluid chromatography, and capillary electrophoresis). This review begins with a brief discussion of chirality before examining the general strategies and commonalities among all of the chiral separation techniques. Rather than exhaustively listing all the chiral selectors and applications, this review highlights significant issues and differences between chiral and achiral separations, providing salient examples from specific classes of chiral selectors where appropriate.

  4. Separation in Binary Alloys

    NASA Technical Reports Server (NTRS)

    Frazier, D. O.; Facemire, B. R.; Kaukler, W. F.; Witherow, W. K.; Fanning, U.

    1986-01-01

    Studies of monotectic alloys and alloy analogs reviewed. Report surveys research on liquid/liquid and solid/liquid separation in binary monotectic alloys. Emphasizes separation processes in low gravity, such as in outer space or in free fall in drop towers. Advances in methods of controlling separation in experiments highlighted.

  5. Water separator

    NASA Technical Reports Server (NTRS)

    Dunn, W. F.; Austin, I. G. (Inventor)

    1964-01-01

    An apparatus for separating liquids from gases or gaseous fluids is described. Features of the apparatus include: (1) the collection and removal of the moisture in the fluid is not dependent upon, or affected by gravity; (2) all the collected water is cyclically drained from the apparatus irrespective of the attitude of the separator; and (3) a fluid actuator is utilized to remove the collected water from the separator.

  6. Battery separators.

    PubMed

    Arora, Pankaj; Zhang, Zhengming John

    2004-10-01

    The ideal battery separator would be infinitesimally thin, offer no resistance to ionic transport in electrolytes, provide infinite resistance to electronic conductivity for isolation of electrodes, be highly tortuous to prevent dendritic growths, and be inert to chemical reactions. Unfortunately, in the real world the ideal case does not exist. Real world separators are electronically insulating membranes whose ionic resistivity is brought to the desired range by manipulating the membranes thickness and porosity. It is clear that no single separator satisfies all the needs of battery designers, and compromises have to be made. It is ultimately the application that decides which separator is most suitable. We hope that this paper will be a useful tool and will help the battery manufacturers in selecting the most appropriate separators for their batteries and respective applications. The information provided is purely technical and does not include other very important parameters, such as cost of production, availability, and long-term stability. There has been a continued demand for thinner battery separators to increase battery power and capacity. This has been especially true for lithiumion batteries used in portable electronics. However, it is very important to ensure the continued safety of batteries, and this is where the role of the separator is greatest. Thus, it is essential to optimize all the components of battery to improve the performance while maintaining the safety of these cells. Separator manufacturers should work along with the battery manufacturers to create the next generation of batteries with increased reliability and performance, but always keeping safety in mind. This paper has attempted to present a comprehensive review of literature on separators used in various batteries. It is evident that a wide variety of separators are available and that they are critical components in batteries. In many cases, the separator is one of the major factors

  7. Separation of Americium from Europium using Camphor-BisTriazinyl Pyridine: A Fundamental Study

    SciTech Connect

    Tevepaugh, Kayron N.; Carrick, Jesse D.; Tai, Serene; Coonce, Janet G.; Delmau, Lætitia H.; Ensor, Dale D.

    2015-10-27

    Among the different components present in spent nuclear fuel, long-lived trivalent actinides are particularly difficult to separate from the shorter-lived lanthanide fission products due to their similar chemical properties. We achieved selective extraction of americium from acidic solution (up to 2M HNO3) containing tenth molar quantities of lanthanides using neutral pyridine-based ligands dissolved in polar diluents. Nitrogen-based Bis Triazinyl Pyridine (BTP) ligands are desirable for both their excellent An/Ln selectivity and incinerability. Our results pertaining to ligand solubility, kinetics, hydrolytic stability, and extraction performance in various nitric acid environments are presented.

  8. Separation of Americium from Europium using Camphor-BisTriazinyl Pyridine: A Fundamental Study

    DOE PAGES

    Tevepaugh, Kayron N.; Carrick, Jesse D.; Tai, Serene; ...

    2015-10-27

    Among the different components present in spent nuclear fuel, long-lived trivalent actinides are particularly difficult to separate from the shorter-lived lanthanide fission products due to their similar chemical properties. We achieved selective extraction of americium from acidic solution (up to 2M HNO3) containing tenth molar quantities of lanthanides using neutral pyridine-based ligands dissolved in polar diluents. Nitrogen-based Bis Triazinyl Pyridine (BTP) ligands are desirable for both their excellent An/Ln selectivity and incinerability. Our results pertaining to ligand solubility, kinetics, hydrolytic stability, and extraction performance in various nitric acid environments are presented.

  9. Phase behavior and molecular dynamics simulation studies of new aqueous two-phase separation systems induced by HEPES buffer.

    PubMed

    Taha, Mohamed; Khoiroh, Ianatul; Lee, Ming-Jer

    2013-01-17

    Here, for the first time, we show that with addition of a biological buffer, 4-(2-hydroxyethyl)piperazine-1-ethanesulfonic acid (HEPES), into aqueous solutions of tetrahydrofuran (THF), 1,3-dioxolane, 1,4-dioxane, 1-propanol, 2-propanol, tert-butanol, acetonitrile, or acetone, the organic solvent can be excluded from water to form a new liquid phase. The phase diagrams have been determined at ambient temperature. In order to understand why and how a zwitterion solute (HEPES) induced phase separation of the investigated systems, molecular dynamics (MD) simulation studies are performed for HEPES + water + THF system. The MD simulations were conducted for the aqueous mixtures with 12 different compositions. The reliability of the simulation results of HEPES in pure water and beyond the phase separation mixtures was justified by comparing the densities obtained from MD with the experimental values. The simulation results of HEPES in pure THF and in a composition inside the phase separation region were justified qualitatively. Interestingly, all HEPES molecules entirely aggregated in pure THF. This reveals that HEPES is insoluble in pure THF, which is consistent with the experimental results. Even more interestingly, the MD simulation for the mixture with composition inside the phase separation region showed the formation of two phases. The THF molecules are squeezed out from the water network into a new liquid phase. The hydrogen bonds (HBs), HB lifetime, HB Gibbs energy (ΔG), radial distribution functions (RDFs), coordination numbers (CNs), electrostatic interactions, and the van der Waals interactions between the different species have been analyzed. Further, MD simulations for the other phase separation systems by choosing a composition inside the two liquids region for each system were also simulated. Our findings will therefore pave the way for designing new benign separation auxiliary agents.

  10. Fatigue study of ultra-runners: Presentation of a new approach for the separation of GRF signals components

    NASA Astrophysics Data System (ADS)

    Zakaria, F. A.; El Badaoui, M.; Lamraoui, M.; Khalil, M.

    2016-06-01

    In recent years, ultra-marathon running has become increasingly popular in many countries around the world. The ability to run for long hours has played a role in human evolution. It is known that the etiology of fatigue depends upon the exercise under consideration. In order to characterize and find a full description of the fatigue and its effects on the human locomotion mechanics, and to extract the relevant parameters and information for diagnosis, we have investigated the changes in running mechanics. More specifically, the ground reaction force (GRF) manifestations of fatigue, have been investigated by using advanced signal processing tools. GRF signals are composed of two parts: an active peak representing the propulsive force and a passive peak that represents the impact force. The impact force is the major factor indicating the reaction of muscle, that may reflects the fatigue state and performance of the muscle. In this article, we focused on the treatment of biomechanical signals for the purpose of GRF components separation where the aim is to separate the contribution of the active components and the passive components. For this reason, we proposed a new algorithm, based on the Gaussian decomposition and non-linear least squares method that will achieve the desired goal. We then compare the results of separation with a proposed BSS based method i.e. "FastICA algorithm". We also compare the results with that obtained by Sabri et al. [1-3] who used different BSS techniques which gave bad and fair results. The separated passive signal is then proved to contain a mixture of a deterministic phenomenon and a stationary random phenomenon, where both phenomena are separated using the cepstral editing procedure (CEP) method. CEP is applied after signal synchronization using method with maximization of the inter-correlation function. The random part is then proved to be cyclostationary of order 2. A real application examined the biomechanical changes occurring in

  11. Characterization of Cerro Negro crude. Part I. Physical and chemical separations. [Project shared by Bartlesville Energy Technology Center, US DOE, and Institute de Tecnologico del Venezolana Petroleo

    SciTech Connect

    Grizzle, P.L.; Green, J.B.; Sanchez, V.; Murgia, E.; Lubkowitz, J.

    1981-09-01

    The scheme couples distillation and ion exchange and solid liquid chromatography in an attempt to prepare narrow-boiling, chemically unique fractions, which can be analyzed further or can supply data for process development. For evaluation of the separation approach, a Cerro Negro crude from the Venezuelan Orinoco basin has been studied in a cooperative program between the United States Department of Energy and the Institute de Tecnologico del Venezolana Petroleo. These fractions may be analyzed by ir, uv, fluorescence, and nuclear magnetic resonance spectroscopy, as well as various mass spectroscopy methods. The approach appears to be promising. 5 figures, 6 tables.

  12. Metabonomics study of liver cancer based on ultra performance liquid chromatography coupled to mass spectrometry with HILIC and RPLC separations.

    PubMed

    Chen, Jing; Wang, Wenzhao; Lv, Shen; Yin, Peiyuan; Zhao, Xinjie; Lu, Xin; Zhang, Fengxia; Xu, Guowang

    2009-09-14

    In this study, urinary metabolites from liver cancer patients and healthy volunteers were studied by a metabonomic method based on ultra performance liquid chromatography coupled to mass spectrometry. Both hydrophilic interaction chromatography (HILIC) and reversed-phase liquid chromatography (RPLC) were used to separate the urinary metabolites. Principle component analysis (PCA) and partial least squares to latent structure-discriminant analysis (PLS-DA) models were built to separate the healthy volunteers from the liver cancer patients and to find compounds that are expressed in significantly different amounts between the two populations. 21 metabolite ions were considered as potential biomarkers according to the Variable importance in the Project (VIP) value and S-plot. Compared with RPLC, a more sensitive and stable response can be recorded in HILIC mode due to the high content of organic solvent used. Moreover, the liver cancer group and the healthy volunteers can be better separated based on the data from the HILIC separation, which indicates that HILIC is suitable for urinary metabonomic analysis. In HILIC mode, several polar compounds related to arginine and proline metabolism, alanine and aspartate metabolism, lysine degradation, nicotinate and nicotinamide metabolism were found to be significantly changed in the concentrations of the two different populations: healthy and cancer. In contrast, in RPLC mode, these changed compounds are related to fatty acids oxidation.

  13. Computational study of supersonic turbulent-separated flows using partially averaged Navier-stokes method

    NASA Astrophysics Data System (ADS)

    Luo, Dahai; Yan, Chao; Wang, Xiaoyong

    2015-02-01

    Separation commonly exists in the flows around flight vehicles and also in the internal combustor flows. Simulation of high-speed turbulent-separated flows using a reliable computational design tool is crucial for the development of supersonic and hypersonic vehicles. In this paper, we present the computational results of supersonic base and ramped-cavity flows at high Reynolds numbers using the partially averaged Navier-Stokes (PANS) method. The current PANS models are based on the Menter SST turbulence model and also the Wilcox k-ω model. Results from PANS simulations are compared in detail with the available experimental data. The effect of the resolution control parameter fk (the ratio of unresolved-to-total kinetic energy) relevant to the PANS method is investigated. More turbulent flow structures are resolved as expected with decreasing fk, but it does not mean better results can be obtained. Spatially varying and dynamically updated fk in PANS simulations has been performed. Results from variable fk PANS simulations show good agreement with the experiment and great improvement when compared to Reynolds averaged Navier-Stokes (RANS) computation and constant fk PANS simulations.

  14. Conceptual study of the cryocascade for pumping, separation and recycling of ITER torus exhaust

    SciTech Connect

    Mack, A.; Perinic, D.

    1994-12-31

    For pumping, separation and recycling of the ITER plasma exhaust, a pumping system working reliably under ambient and operating conditions of the ITER reactor is required. The pump is exposed to a magnetic field of about 3 T and has to be resistant to radioactive irradiation of 10{sup 9} rad. In the burn and dwell phase, a gas mixture consisting of hydrogen isotopes, helium ash and impurities has to be pumped at the pressure range of 10{sup {minus}2} - 10{sup {minus}1} mbar. Within the framework of the European Fusion Technology Programme, the concept of a primary cryopump for use in ITER is being prepared at KfK. The cryocascade concept is planned to include three pump stages. These pump stages, which are connected in series, consist of individual chambers that may be separated from each other by means of cold valves. In the first stage, the impurities of the reactor exhaust gas are frozen out at 20-30 K. Settling of the hydrogen isotopes H/D/T on the 5 K cryosurfaces takes place in the second stage. This stage is made up of two parallel chambers, which can be switched from the pumping to the regeneration mode or vice versa. The helium fraction is bound in the downstream 5 K adsorption stage.

  15. An experimental study of surface pressure fluctuations in a separating turbulent boundary layer

    NASA Technical Reports Server (NTRS)

    Simpson, Roger L.; Ghodbane, M.; Mcgrath, B. E.

    1987-01-01

    Measurements of streamwise velocity fluctuation and surface pressure fluctuation spectra and wavespeeds are reported for a well-documented separating turbulent boundary layer. Because a portion of the acoustic pressure fluctuations is the same across the nominally two-dimensional turbulent flow, it is possible to decompose two microphone signals and obtain directly the turbulent flow contributions to the surface pressure spectra. The rms surface pressure fluctuation p' and spectra phi(omega) increase through the adverse pressure gradient attached flow region and the detached flow zone and scale on the maximum turbulent shearing stress tau(M); p'/tau(M) increases to the detachment location and decreases downstream due to the rapid movement of the pressure-fluctuation-producing motions away from the wall after the beginning of intermittent backflow. At lower frequencies for the attached flow phi(omega) is approximately omega to the -0.7 while phi(omega) is approximately omega to the -3 at higher frequencies. After the beginning of intermittent backflow, phi(omega) varies with omega at low frequencies and omega to the -3 at high frequencies; farther downstream the lower frequency range varies with omega to the 2.4. The surface pressure fluctuation celerity for the attached flow increases with frequency and agrees with the semi-logarithmic overlap equation of Panton and Linebarger. After the beginning of the separation process, the wavespeed decreases because of the oscillation of the instantaneous wavespeed direction and the streamwise coherence decreases drastically.

  16. Separation and characterization of mares' milk alpha(s1)-, beta-, kappa-caseins, gamma-casein-like, and proteose peptone component 5-like peptides.

    PubMed

    Egito, A S; Miclo, L; López, C; Adam, A; Girardet, J M; Gaillard, J L

    2002-04-01

    The equine alpha(s1)- and beta-caseins (CN) were purified by chromatography on DEAE-cellulose and by reversed-phase HPLC. The alpha(s1)-, beta-, and kappa-CN were characterized either by monodimensional urea-PAGE or sodium dodecylsulfate (SDS)-PAGE or by bidimensional electrophoresis. Kappa-casein was characterized after electrophoresis by glycoprotein-specific staining. To identify alpha(s1)-CN without ambiguity, internal sequences were determined after trypsin or chymosin digestion of purified alpha(s1)-CN. These sequences, that could be estimated to correspond to 62% of the full protein, presented strong identities with regions of alpha(s1)-CN primary structures of other species. In particular, 51, 48, 43, and 40% identities were obtained with corresponding regions of sow, dromedary, cow, and human alpha(s1)-CN, respectively. On the other hand, trace amounts of equine gamma-CN-like and proteose peptone component 5-like peptides were found in the whole CN. They were identified by microsequencing and corresponded to beta-CN peptides generated by plasmin action on the whole CN. The equine alpha(s1), beta-, and kappa-CN were separated by bidimensional electrophoresis in numerous isoelectric variants with apparent isoelectric points distributed between pH 4.4 to 6.3, 4.4 to 5.9, and 3.5 to 5.5, respectively. The beta- and kappa-CN displayed a more acidic character in the mare than in the cow.

  17. Rapid separation and characterization of diterpenoid alkaloids in processed roots of Aconitum carmichaeli using ultra high performance liquid chromatography coupled with hybrid linear ion trap-Orbitrap tandem mass spectrometry.

    PubMed

    Xu, Wen; Zhang, Jing; Zhu, Dayuan; Huang, Juan; Huang, Zhihai; Bai, Junqi; Qiu, Xiaohui

    2014-10-01

    The lateral root of Aconitum carmichaeli, a popular traditional Chinese medicine, has been widely used to treat rheumatic diseases. For decades, diterpenoid alkaloids have dominated the phytochemical and biomedical research on this plant. In this study, a rapid and sensitive method based on ultra high performance liquid chromatography coupled with linear ion trap-Orbitrap tandem mass spectrometry was developed to characterize the diterpenoid alkaloids in Aconitum carmichaeli. Based on an optimized chromatographic condition, more than 120 diterpenoid alkaloids were separated with good resolution. Using a systematic strategy that combines high resolution separation, highly accurate mass measurements and a good understanding of the diagnostic fragment-based fragmentation patterns, these diterpenoid alkaloids were identified or tentatively identified. The identification of these chemicals provided essential data for further phytochemical studies and toxicity research of Aconitum carmichaeli. Moreover, the ultra high performance liquid chromatography with linear ion trap-Orbitrap mass spectrometry platform was an effective and accurate tool for rapid qualitative analysis of secondary metabolite productions from natural resources.

  18. Nonlinear effects on western boundary current structure and separation: a laboratory study

    NASA Astrophysics Data System (ADS)

    Pierini, S.; Falco, P.; Zambardino, G.; McClimans, T. A.; Ellingsen, I.

    2009-04-01

    The role played by nonlinear effects in shaping the structure of barotropic western boundary currents (WBCs) and in determining WBC separation from the coast has been investigated through laboratory simulations by means of the 5-m-diameter Coriolis rotating basin at SINTEF (Trondheim, Norway) in the framework of the HYDRALAB-III project. The laboratory setup consists of two parallel rectangular channels separated by an island and linked by two curved connections: in the first channel, a piston is forced at a constant speed U ranging from 0.05 to 3 cm/s over a distance of 2.5 m, producing a virtually unsheared current at the entrance of the second channel. In the latter, a linear reduction of the water depth provides the topographic beta-effect that produces the westward intensification. Nearly steady currents are obtained and measured photogrammetrically over a region of about 1 m2. The broad range of piston speeds permitted by the mechanical apparatus has allowed us to achieve an unprecedented coverage of the range of nonlinearity for WBCs in terms of experimental data, so that the cross-stream WBC profile could be analyzed from the nearly linear Munk-type case (e.g., for U=0.1 cm/s with T=30 s, where T is the rotation period of the basin) up to the more realistic highly nonlinear limit (particularly significant is the case U=1 cm/s and T=30 s, which is close to be dynamically similar to the Gulf Stream). Thanks to the large size of the rotating basin, cross-stream widths of the simulated WBC as large as 80 cm could be obtained. Moreover, in order to analyze the process of WBC separation, coastal variations have been introduced along the western boundary in the form of wedge-shaped continents with different coastline orientations, whose northern limit corresponds to an idealized Cape Hatteras. While weak WBCs follow the coast also past the cape, for sufficiently strong nonlinear effects the current detaches from the coast as a consequence of flow deceleration

  19. A fine coal circuitry study using column flotation and gravity separation. Technical report, September 1--November 30, 1994

    SciTech Connect

    Honaker, R.Q.; Reed, S.

    1994-12-31

    Column flotation provides excellent recovery of ultrafine coal while producing low ash content concentrates. However, column flotation is not efficient for treating fine coal containing significant amounts of mixed-phase particles. Fortunately, enhanced gravity separation has proved to have the ability to treat the mixed-phased particles more effectively. A disadvantage of gravity separation is that ultrafine clay particles are not easily rejected. Thus, a combination of these two technologies may provide a circuit that maximizes both the ash and sulfur rejection that can be achieved by physical coal cleaning while maintaining a high energy recovery. This project is studying the potential of using different combinations of gravity separators, i.e., a Floatex hydrosizer and a Falcon Concentrator, and a proven flotation column, which will be selected based on previous studies by the principle investigator. The gravity/flotation circuits will be compared based on their optimum separation performance which will consider ash and total sulfur rejection and energy recovery as well as the probable error (E{sub p}) value obtained from washability analyses. During this reporting period, multi-stage treatment using the Falcon concentrator was conducted on a refuse pond ({minus}100 mesh) coal sample and a {minus}28 mesh run-of-mine coal sample. The results suggest that the Falcon concentrator can make an ideal separation for either sample in a single process. Recleaning was found to improve product grade, however, recovery was reduced sharply. In addition, the groups involved with the in-plant testing of the Floatex Hydrosizer met and organized the test plan which will be conducted at Kerr-McGee`s Galatia preparation plant during the next reporting period. Coal samples for the circuitry tests will be collected during, this time period.

  20. Separation and characterization of metallothionein in the liver of sea turtles by high performance liquid chromatographylinductively coupled plasma-mass spectrometry

    NASA Astrophysics Data System (ADS)

    Shinsuke, T.; Yasumi, A.; Takashi, K.

    2003-05-01

    To investigate whether trace metals bind to metallothioneins (MTs) in the hepatocytosol of green turtles (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata), MT fraction was obtained by ultracentrifugation and gel filtration methods. MTs separated from hepatocytosol were further purified and characterized by high performance liquid chromatography/inductively coupled plasma-mass spectrometry. In addition, the involvement of MTs in the accumulation of trace metals in the liver of sea turtle was examine. Gel filtration analysis showed that significant amounts of Cu, Zn, Ag and Cd were bound to MT in the cytosol of sea turtles, suggesting that such trace metals were primarily detoxified by interaction with MTs in the liver. Elution profiles of these trace metals by anion-exchange chromatography were different between green turtles and hawksbill turtles. These results suggest the presence of multiple isoforms of MT in the liver of both sea turtles; however, constituents of isoforms were different between green and hawksbill turtles. In both species, we observed the elevation of the height of a specific peak in elution profile with an increase in Cu concentration in hepatocytosol. This result suggests the presence of a novel MT isoform related to copper accumulation in the liver of sea turtles.

  1. Preparation and characterization of poly(triallyl isocyanurate-co-trimethylolpropane triacrylate) monolith and its applications in the separation of small molecules by liquid chromatography.

    PubMed

    Zhong, Jing; Hao, Mengbei; Li, Ruo; Bai, Ligai; Yang, Gengliang

    2014-03-14

    A new polymeric monolith was prepared in stainless-steel column and fused-silica capillary, respectively, by atom transfer radical polymerization technique. In the polymerization, triallyl isocyanurate (TAIC) was used as the functional monomer; trimethylolpropane triacrylate (TMPTA) as the crosslinking agent; polyethylene glycol 200 and 1,2-propanediol as the co-porogens; carbon tetrachloride as the initiator and ferrous chloride as the catalyst. The conditions of polymerization were optimized. Morphology of the prepared poly(TAIC-co-TMPTA) monolith was investigated by scanning electron microscopy; pore properties were assayed by mercury porosimetry and nitrogen adsorption. The characterization indicated that the prepared reversed-phase monolith possessed uniform structure, good permeability and mechanical stability. The column was used as the stationary phase of reversed phase high performance liquid chromatography (RP-HPLC) and capillary liquid chromatography (CLC) to separate the mixture of aromatic compounds. The new column performed around 125,000 theoretical plates per meter. The column showed good reproducibility: the relative standard deviation values of the retention factor values for aromatic compounds were less than 1.52% (n=7, column-to-column).

  2. Magnetically separable CuFe2O4/AgBr composite photocatalysts: Preparation, characterization, photocatalytic activity and photocatalytic mechanism under visible light

    NASA Astrophysics Data System (ADS)

    Zhao, Yalei; Lin, Cuiping; Bi, Huijie; Liu, Yonggang; Yan, Qishe

    2017-01-01

    The CuFe2O4 and CuFe2O4/AgBr composites with different CuFe2O4 contents were prepared by a facile sol-gel and hydrothermal method, respectively. The as-synthesized photocatalysts were characterized by means of powder X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and UV-vis diffuse reflectance spectrum (UV-vis DRS). Their magnetic properties, photocatalytic degradation activities on methyl orange (MO) and tetracycline hydrochloride (TC) solution and photocatalytic mechanism were investigated in detail. The results revealed that the CuFe2O4/AgBr composites exhibited significantly higher photocatalytic activities than the pure CuFe2O4. The enhanced photocatalytic activity could be attributed to the matched band structure of two components and more effective charge transportation and separations. In addition, the quenching investigation of different scavengers demonstrated that h+, rad OH, rad O2- reactive species played different roles in the decolorization of MO and degradation of TC.

  3. Isolation and Characterization, Including by X-ray Crystallography, of Contact and Solvent-Separated Ion Pairs of Silenyl Lithium Species.

    PubMed

    Pinchuk, Daniel; Mathew, Jomon; Kaushansky, Alexander; Bravo-Zhivotovskii, Dmitry; Apeloig, Yitzhak

    2016-08-22

    Reaction of bromoacylsilane 1 (pink solution) with tBu2 MeSiLi (3.5 equiv) in a 4:1 hexane:THF solvent mixture at -78 °C to room temperature yields the solvent separated ion pair (SSIP) of silenyl lithium E-[(tBuMe2 Si)(tBu2 MeSi)C=Si(SiMetBu2 )](-) [Li⋅4THF](+) 2 a (green-blue solution). Removal of the solvent and addition of benzene converts 2 a into the corresponding contact ion pair (CIP) 2 b (violet-red solution) with two THF molecules bonded to the lithium atom. The 2 a⇌2 b interconversion is reversible upon THF⇌ benzene solvent change. Both 2 a and 2 b were characterized by X-ray crystallography, NMR and UV/Vis spectroscopy, and theoretical calculations. The degree of dissociation of the Si-Li bond has a large effect on the visible spectrum (and thus color) and on the silenylic (29) Si NMR chemical shift, but a small effect on the molecular structure. This is the first report of the X-ray molecular structure of both the SSIP and the CIP of any R2 E=E'RM species (E=C, Si; E'=C, Si; M=metal).

  4. An enzyme immobilized microassay in capillary electrophoresis for characterization and inhibition studies of alkaline phosphatases.

    PubMed

    Iqbal, Jamshed

    2011-07-15

    A simple and fast dynamically coated capillary electrophoretic method was developed for the characterization and inhibition studies of alkaline phosphatases(EC 3.1.3.1). An inside capillary enzymatic reaction was performed, and hydrolysis of the substrate 4-nitrophenylphosphate to 4-nitrophenol was measured. Fused-silica capillary surface was dynamically modified with polycationic polybrene coating. By reversal of the electroosmotic flow (EOF), analysis time was reduced up to 3 min as the anionic analytes were migrated in the same direction as the EOF. Furthermore, the sensitivity of the method was increased using electroinjection through high-field amplified injection. The baseline separation of 4-nitrophenylphosphate and 4-nitrophenol was achieved by employing 50 mM sodium phosphate as the running buffer (pH 8.5), 0.0025% polybrene, and a constant voltage of -15 kV, and the products were detected at 322 nm. Under the optimized conditions, a good separation with high efficiency was achieved. The new method was applied to study enzyme kinetics and inhibitor screening. K(m) and K(i) values obtained with the new CE method were compared well with the standard spectrophotometric method. Dynamic coating of fused-silica capillary gave fast and reproducible separation of substrate and product. The method can be easily optimized for inhibition studies of other isozymes.

  5. [Study on the separation process of pharmacological active total alkaloids from Chelidonium majus L. growing in Georgia].

    PubMed

    Bozhadze, A D; Vachnadze, V Iu; Dzhokhadze, M S; Berashvili, D T; Bakuridze, A Dzh

    2013-04-01

    In present article was studied the separation process of pharmacological active total alkaloids from Chelidonium majus L. growing in Georgia. Alkaloids were extracted from medicinal herbal material and separated by liquid extraction, diluents gas and a microfiltration through membrane equipment. The obtained A1, A2, A3 fractions were analyzed by GC/MS method; in all cases separation proceeds by the principle of extraction of the target alkaloids. It was concluded that the A1 is enriched with α and β cryptopins, and protopin, but homochelidonine and chelidonine are in low contents. As accompanying alkaloid is identified dihydrosanguinarine as an artifact; the A2 is enriched with the maximum contents of stylopine and protopin, but the poor contents of chelidonine and homochelidonine; the A3 is enriched with α and β cryptopins and maximum content of chelidonine. Extraction of alkaloids from Chelidonium majus L. proceeds selectively, but depending on a way of separation of the total alkaloids allows varying qualitative and quantitative consistence of the final product.

  6. Capillary electrophoretic study of dibasic acids of different structures: Relation to separation of oxidative intermediates in remediation

    SciTech Connect

    Yu, Z.; Cocke, D.L.

    1998-09-01

    Dicarboxylic acids are important in environmental chemistry because they are intermediates in oxidative processes involved in natural remediation and waste management processes such as oxidative detoxification and advanced oxidation. Capillary electrophoresis (CE), a promising technique for separating and analyzing these intermediates, has been used to examine a series of dibasic acids of different structures and conformations. This series includes malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, maleic acid, fumaric acid, phthalic acid, and trans, trans-muconic acid. The CE parameters as well as structural variations (molecular structure and molecular isomers, buffer composition, pH, applied voltage, injection mode, current, temperature, and detection wavelength) that affect the separations and analytical results have been examined in this study. Those factors that affect the separation have been delineated. Among these parameters, the pH has been found to be the most important, which affects the double-layer of the capillary wall, the electro-osmotic flow and analyte mobility. The optimum pH for separating these dibasic acids, as well as the other parameters are discussed in detail and related to the development of methods for analyzing oxidation intermediates in oxidative waste management procedures.

  7. Property-close source separation of hazardous waste and waste electrical and electronic equipment--a Swedish case study.

    PubMed

    Bernstad, Anna; la Cour Jansen, Jes; Aspegren, Henrik

    2011-03-01

    Through an agreement with EEE producers, Swedish municipalities are responsible for collection of hazardous waste and waste electrical and electronic equipment (WEEE). In most Swedish municipalities, collection of these waste fractions is concentrated to waste recycling centres where households can source-separate and deposit hazardous waste and WEEE free of charge. However, the centres are often located on the outskirts of city centres and cars are needed in order to use the facilities in most cases. A full-scale experiment was performed in a residential area in southern Sweden to evaluate effects of a system for property-close source separation of hazardous waste and WEEE. After the system was introduced, results show a clear reduction in the amount of hazardous waste and WEEE disposed of incorrectly amongst residual waste or dry recyclables. The systems resulted in a source separation ratio of 70 wt% for hazardous waste and 76 wt% in the case of WEEE. Results show that households in the study area were willing to increase source separation of hazardous waste and WEEE when accessibility was improved and that this and similar collection systems can play an important role in building up increasingly sustainable solid waste management systems.

  8. A Mechanistic Study of Chemically Modified Inorganic Membranes for Gas and Liquid Separations

    SciTech Connect

    Way, J Douglas

    2011-01-21

    This final report will summarize the progress made during the period August 1, 1993 - October 31, 2010 with support from DOE grant number DE-FG03-93ER14363. The objectives of the research have been to investigate the transport mechanisms in micro- and mesoporous, metal oxide membranes and to examine the relationship between the microstructure of the membrane, the membrane surface chemistry, and the separation performance of the membrane. Examples of the membrane materials under investigation are the microporous silica hollow fiber membrane manufactured by PPG Industries, chemically modified mesoporous oxide membranes, and polymer membranes containing microporous oxides (mixed matrix membranes). Analytical techniques such as NMR, FTIR and Raman spectroscopy, thermal analysis, and gas adsorption were used to investigate membrane microstructure and to probe the chemical interactions occurring at the gas-membrane interface.

  9. Deformability-based red blood cell separation in deterministic lateral displacement devices-A simulation study.

    PubMed

    Krüger, Timm; Holmes, David; Coveney, Peter V

    2014-09-01

    We show, via three-dimensional immersed-boundary-finite-element-lattice-Boltzmann simulations, that deformability-based red blood cell (RBC) separation in deterministic lateral displacement (DLD) devices is possible. This is due to the deformability-dependent lateral extension of RBCs and enables us to predict a priori which RBCs will be displaced in a given DLD geometry. Several diseases affect the deformability of human cells. Malaria-infected RBCs, for example, tend to become stiffer than their healthy counterparts. It is therefore desirable to design microfluidic devices which can detect diseases based on the cells' deformability fingerprint, rather than preparing samples using expensive and time-consuming biochemical preparation steps. Our findings should be helpful in the development of new methods for sorting cells and particles by deformability.

  10. Flow separation in out-of-round nozzles, a numerical and experimental study

    NASA Astrophysics Data System (ADS)

    Génin, C.; Stark, R.; Jack, S.

    2015-06-01

    The start-up and shutdown transient phases in rocket engine nozzles generate high side loads. The internal and external flow fluctuations can excite the eigenmodes of the nozzle structure. The flow separation in out-of-round nozzle intensifies the initial structure deformation leading in the worst case to the collapse of the nozzle. In the framework of the DLR internal cooperation program ProTAU, the ovalization of nozzles is being investigated from both the numerical and the experimental point of view. Three nozzle geometries have been designed and deformed applying various methods. The flow behavior in the initially axisymmetric and the ovalized contours has been numerically investigated. The most promising contours will be manufactured as permanently ovalized nozzle models and tested under cold flow conditions.

  11. Computational Study of Fluidic Thrust Vectoring using Separation Control in a Nozzle

    NASA Technical Reports Server (NTRS)

    Deere, Karen; Berrier, Bobby L.; Flamm, Jeffrey D.; Johnson, Stuart K.

    2003-01-01

    A computational investigation of a two- dimensional nozzle was completed to assess the use of fluidic injection to manipulate flow separation and cause thrust vectoring of the primary jet thrust. The nozzle was designed with a recessed cavity to enhance the throat shifting method of fluidic thrust vectoring. The structured-grid, computational fluid dynamics code PAB3D was used to guide the design and analyze over 60 configurations. Nozzle design variables included cavity convergence angle, cavity length, fluidic injection angle, upstream minimum height, aft deck angle, and aft deck shape. All simulations were computed with a static freestream Mach number of 0.05. a nozzle pressure ratio of 3.858, and a fluidic injection flow rate equal to 6 percent of the primary flow rate. Results indicate that the recessed cavity enhances the throat shifting method of fluidic thrust vectoring and allows for greater thrust-vector angles without compromising thrust efficiency.

  12. A study of heart sound and lung sound separation by independent component analysis technique.

    PubMed

    Chien, Jen-Chien; Huang, Ming-Chuan; Lin, Yue-Der; Chong, Fok-ching

    2006-01-01

    In the hospital, using percussion and auscultation are the most common ways for physical examination. Recently, in order to develop tele-medicine and home care system and to assist physician getting better auscultation results; electric stethoscope and computer analysis have become an inevitable trend. However, two important physical signals heart sound and lung sound recorded from chest overlap on spectrum chart. Therefore, in order to reduce human factor (ex. misplace or untrained of using) and minimize correlated effect in computer analysis; it's necessary for separated heart sound and lung sound. Independent component analysis can divide these sounds efficiency. In this paper, we use two microphones to collect signals from left and right chest. We have successfully divide heart and lung sounds by fast ICA algorithm. Therefore, it can assist physician examine and also using on tele-medicine and home care by this way.

  13. Coarse-coal hydrotransport studies using the separate effects test stand: FY 1980-1981

    SciTech Connect

    Powers, T.B.

    1981-09-01

    The Separate Effects Test Stand (SETS) was built to evaluate the rotating pipe-wheel stand concept for hydrotransport testing and to obtain hydrotransport data in support of the US Department of Energy's Hydraulic Transport Research Facility (HTRF). The SETS program involved three phases of testing. The first phase was to evaluate the wheel test stand as an adequate mechanism for testing the hydrotransport of coarse-particle coal through pipe. The second phase was to obtain preliminary data on coal head loss (flow pressure drop) during hydrotransport. The third phase was to determine the effects of coal hydrotransport on water quality. Other data obtained during the program included pipe wear and the size degradation of coal particles. The SETS was tested with water only and the resultant head loss data were compared with head loss values recorded for water flow in staight pipe. These tests were run to determine how well the SETS modeled straight pipe flow.

  14. Tree Canopy Characterization for EO-1 Reflective and Thermal Infrared Validation Studies: Rochester, New York

    NASA Technical Reports Server (NTRS)

    Ballard, Jerrell R., Jr.; Smith, James A.

    2002-01-01

    The tree canopy characterization presented herein provided ground and tree canopy data for different types of tree canopies in support of EO-1 reflective and thermal infrared validation studies. These characterization efforts during August and September of 2001 included stem and trunk location surveys, tree structure geometry measurements, meteorology, and leaf area index (LAI) measurements. Measurements were also collected on thermal and reflective spectral properties of leaves, tree bark, leaf litter, soil, and grass. The data presented in this report were used to generate synthetic reflective and thermal infrared scenes and images that were used for the EO-1 Validation Program. The data also were used to evaluate whether the EO-1 ALI reflective channels can be combined with the Landsat-7 ETM+ thermal infrared channel to estimate canopy temperature, and also test the effects of separating the thermal and reflective measurements in time resulting from satellite formation flying.

  15. A parametric study of three-dimensional separation at a wing/body junction for supersonic free-stream conditions

    NASA Technical Reports Server (NTRS)

    Lakshmanan, B.; Tiwari, S. N.; Hussaini, M. Y.

    1989-01-01

    The problem of three-dimensional separation at a wing/body junction has been investigated numerically using a three-dimensional Navier-Stokes code which employs the MacCormack's time split finite volume technique. An algebraic grid generation technique is used for generating the grid at a wing/body junction. Specific computational results on velocity and pressure distribution in the separated flow region are compared with the experimental results. A parametric study of flow parameters such as Mach number and Reynolds number have been carried out to understand their effect in interaction flow field. The parametric study indicates a strong dependency of the number of vortices at the junction on Mach number and Reynolds number.

  16. Isothermal separation processes

    NASA Technical Reports Server (NTRS)

    England, C.

    1982-01-01

    The isothermal processes of membrane separation, supercritical extraction and chromatography were examined using availability analysis. The general approach was to derive equations that identified where energy is consumed in these processes and how they compare with conventional separation methods. These separation methods are characterized by pure work inputs, chiefly in the form of a pressure drop which supplies the required energy. Equations were derived for the energy requirement in terms of regular solution theory. This approach is believed to accurately predict the work of separation in terms of the heat of solution and the entropy of mixing. It can form the basis of a convenient calculation method for optimizing membrane and solvent properties for particular applications. Calculations were made on the energy requirements for a membrane process separating air into its components.

  17. Switching Monopolar Radiofrequency Ablation Using a Separable Cluster Electrode in Patients with Hepatocellular Carcinoma: A Prospective Study

    PubMed Central

    Choi, Jin Woo; Lee, Jeong Min; Lee, Dong Ho; Yoon, Jeong-Hee; Suh, Kyung-Suk; Yoon, Jung-Hwan; Kim, Yoon Jun; Lee, Jeong-Hoon; Yu, Su Jong; Han, Joon Koo

    2016-01-01

    Objective This study was conducted to evaluate the outcomes of multi-channel switching RFA using a separable cluster electrode in patients with HCC. Methods From November 2011 to July 2013, 79 patients with 98 HCCs < 5 cm were enrolled and treated with RFA using a multi-channel switching radiofrequency system and a separable cluster electrode under the guidance of a real-time fusion imaging system. The primary and secondary endpoints were the 3-year local tumor progression (LTP) rate and recurrence-free survival (RFS) rate, respectively. For post hoc analyses, LTP, RFS, and major complication rates were retrospectively compared with a historical control group treated with RFA using the same radiofrequency system but with multiple internally-cooled electrodes. Results The technique success rate of the 98 tumors was 100%. Cumulative 1-year, 2-year, and 3-year LTP rates were 3.4%, 6.9%, and 12.4%, respectively. For patient-level data, cumulative 1-year, 2-year, and 3-year RFS rates were 83.9%, 68.6%, and 45.4%, respectively. On post hoc analyses, none of the baseline characteristics showed a significant difference between the separable cluster electrode and multiple internally-cooled electrodes group. Cumulative LTP and RFS rates of the two groups also showed no significant difference (p = 0.401 and p = 0.881, respectively). Finally, major complication rates of the separable cluster electrode group (5.0%, 4/79) and multiple internally-cooled electrodes group (5.9%, 4/74) were also comparable (p = 1.000). Conclusion Switching monopolar RFA using a separable cluster electrode is a feasible and efficient technique for the treatment of HCCs smaller than 5 cm, providing comparable local tumor control to multiple internally-cooled electrodes. Trial Registration ClinicalTrials.gov NCT02745483 PMID:27575787

  18. A CASE STUDY ILLUSTRATING THE IMPORTANCE OF ACCURATE SITE CHARACTERIZATION

    EPA Science Inventory

    Too frequently, researchers rely on incomplete site characterization data to determine the placement of the sampling wells. They forget that it is these sampling wells that will be used to evaluate the effectiveness of their research efforts. This case study illustrates the eff...

  19. Preparation and characterization of a porous scaffold based on poly(D,L-lactide) and N-hydroxyapatite by phase separation.

    PubMed

    Wang, Xiu Hong; Shi, Shuai; Guo, Gang; Fu, Shao Zhi; Fan, Min; Luo, Feng; Zhao, Xia; Wei, Yu Quan; Qian, Zhi Yong

    2011-01-01

    In this study, a series of porous scaffolds were prepared from poly(D,L-lactide) (PLA) and nanohydroxyapatite (HA) using the phase separation method. HA/PLA composite membranes and PLA membranes with a microporous structure (pore size around 10-20 μm) were observed by scanning electron microscopy and these micropores were well distributed throughout the PLA membranes. The surface morphology of HA/PLA composite membranes was significantly improved compared to pure PLA membrane. Also, the mechanical property and contact angle of composite membranes were different from that of pure PLA films. The immortalized rat osteoblastic ROS 17/2.8 cell line was used in this research to study the cell adhesion and proliferation behavior, and the results indicated that composite membranes had great cell affinity and good biocompatibility.

  20. Status of IAEA CRP on Study of Process-Losses in Separation Processes in Partitioning and Transmutation Systems in View of Minimizing Long-Term Environmental Impacts

    SciTech Connect

    Ahn, J.; Bimova, K.C.; Bychkov, A.; Kormilitsyn, M.; Inoue, T.; Koch, L.; Nagarajan, K.; Nawada, H.; Ye, Y.; Yoo, J.H.

    2007-07-01

    Coordinated Research Project (CRP) was initiated in 2002 by IAEA to enable Member States in developing methodologies for reducing radio-toxic discharge to the environment from nuclear fuel cycle activities and in paving the way for sustainability of nuclear energy. In the past three Research Coordination Meetings (RCM), the following areas of research were examined upon: (1)Basic studies to compare dry partitioning process with aqueous partitioning process; (2)Defining proliferation resistance attributes of partitioning processes; (3) Advanced characterization methods for actinides for measuring the possible material holdup;( 4)Minimization of actinides losses in the waste fraction from the partitioning process;(5)Establishment of separation criteria of partitioning process to minimize environmental impact; and (6)Defining environmental impact associated with partitioning processes. The final TECDOC is currently being prepared to summarize the activities of this CRP. (authors)

  1. Separation and purification of soluble polymers and cell wall fractions from wheat, rye and hull less barley endosperm flours for structure-nutrition studies.

    PubMed

    Comino, Penny; Shelat, Kinnari; Collins, Helen; Lahnstein, Jelle; Gidley, Michael J

    2013-12-11

    The nutritional values associated with the cell walls of cereal endosperm flours are due to a combination of solubilized arabinoxylan and (1-3,1-4)-β-d-glucan as well as residual nonsolubilized cell wall material. In order to investigate structure-nutrition relationships, an appropriate method for the complete functional and structural characterization of cell wall polysaccharides in various cereal endosperm flours is described. This involves the separation of soluble polymers and the residual cell wall fraction without using organic solvents, and the fractionation of soluble polymers into arabinoxylan- and (1-3,1-4)-β-d-glucan-rich fractions for subsequent analysis. This methodology is applied to endosperm flours from wheat, hull-less barley and rye, and could be extended to include studies on the effects of food processing with respect to yield and characteristics of the three fractions in order to better understand the structural basis for nutritional functionality.

  2. Separation and Characterization of Angiotensin I Converting Enzyme (ACE) Inhibitory Peptides from Saurida elongata Proteins Hydrolysate by IMAC-Ni2+

    PubMed Central

    Sun, Lixia; Wu, Shanguang; Zhou, Liqin; Wang, Feng; Lan, Xiongdiao; Sun, Jianhua; Tong, Zhangfa; Liao, Dankui

    2017-01-01

    Lizard fish protein hydrolysates (LFPH) were prepared from Lizard fish (Saurida elongata) proteins possessing powerful angiotensin I converting enzyme (ACE) inhibitory activity and the fraction (LFPH-I) with high ACE inhibitory activity was obtained through ultrafiltration. The active Fraction (F2) was isolated from LFPH-I using immobilized metal affinity chromatography (IMAC-Ni2+). Analysis of amino acid levels revealed that F2 eluted from IMAC was enriched in Met, His, Tyr, Pro, Ile, and Leu compared to the crude peptide LFPH-I. F2 with the high ACE inhibitory activity (IC50 of 0.116 mg·mL−1) was further separated by a reverse-phase column to yield a novel ACE inhibitory peptide with IC50 value of 52 μM. The ACE inhibitory peptide was identified as Arg-Tyr-Arg-Pro, RYRP. The present study demonstrated that IMAC may be a useful tool for the separation of ACE inhibitory peptides from protein hydrolysate. PMID:28212269

  3. Coal liquefaction process streams characterization and evaluation: Application of liquid chromatographic separation methods to THF-soluble portions of integrated two-stage coal liquefaction resids

    SciTech Connect

    Green, J.B.; Pearson, C.D.; Young, L.L.; Green, J.A. )

    1992-05-01

    This study demonstrated the feasibility of using non-aqueous ion exchange liquid chromatography (NIELC) for the examination of the tetrahydrofuran (THF)-soluble distillation resids and THF-soluble whole oils derived from direct coal liquefaction. The technique can be used to separate the material into a number of acid, base, and neutral fractions. Each of the fractions obtained by NIELC was analyzed and then further fractionated by high-performance liquid chromatography (HPLC). The separation and analysis schemes are given in the accompanying report. With this approach, differences can be distinguished among samples obtained from different process streams in the liquefaction plant and among samples obtained at the same sampling location, but produced from different feed coals. HPLC was directly applied to one THF-soluble whole process oil without the NIELC preparation, with limited success. The direct HPLC technique used was directed toward the elution of the acid species into defined classes. The non-retained neutral and basic components of the oil were not analyzable by the direct HPLC method because of solubility limitations. Sample solubility is a major concern in the application of these techniques.

  4. Studies of ion species separation in ICF-relevant plasmas at OMEGA

    NASA Astrophysics Data System (ADS)

    Rinderknecht, Hans; Wilks, Scott; Amendt, Peter; Ross, Steve; Park, Hye-Sook; Gatu Johnson, Maria; Frenje, Johan; Li, Chikang; Seguin, Fredrick; Sio, Hong; Petrasso, Richard; Rosenberg, Michael; Forrest, Chad; Glebov, Vladimir; Stoeckl, Christian; Sangster, Craig; Zylstra, Alex; Hoffman, Nelson; Kwan, Tom; Larroche, Olivier

    2015-11-01

    Plasmas produced in high-energy density (HED) and inertial confinement fusion (ICF) experiments generally contain multiple ion species, which allows for multiple-ion species dynamics that are not simulated in typical single-ion fluid hydro codes. In implosions of D3He-gas filled thin-glass spheres on the OMEGA laser facility, comprehensive nuclear diagnostics were used to infer the composition of the fuel during nuclear production, demonstrating that the deuterium fraction was reduced during the implosion of the fuel. Hydrodynamic simulations including an ion diffusion model indicate that pressure, temperature, and potential gradients drive diffusive separation of the ion species, producing better agreement with the experiments than standard hydrodynamic codes. The results of fully kinetic (Vlasov-Fokker-Planck and PIC) simulations confirm the importance of multi-species dynamics to the evolution of these experiments. Implications for multi-species (DT) cryogenic implosions on the National Ignition Facility will be addressed. This work was partially supported by the US DOE, NLUF, LLE, and GA.

  5. Computational study on the progressive factorization of composite polymer knots into separated prime components.

    PubMed

    Tubiana, Luca

    2014-05-01

    Using Monte Carlo simulations and advanced knot localization methods, we analyze the length and distribution of prime components in composite knots tied on freely jointed rings. For increasing contour length, we observe the progressive factorization of composite knots into separated prime components. However, we observe that a complete factorization, equivalent to the "decorated ring" picture, is not obtained even for rings of contour lengths N ≃ 3 N(0), about tens of times the most probable length of the prime knots tied on the rings. The decorated ring hypothesis has been used in the literature to justify the factorization of composite knot probabilities into the knotting probabilities of their prime components. Following our results, we suggest that such a hypothesis may not be necessary to explain the factorization of the knotting probabilities, at least when polymers excluding volume is not relevant. We rationalize the behavior of the system through a simple one-dimensional model in which prime knots are replaced by slip links randomly placed on a circle, with the only constraint being that the length of the loops has the same distribution as that of the length of the corresponding prime knots.

  6. The non-separability of ``dielectric'' and ``mechanical'' friction in molecular systems: A simulation study

    NASA Astrophysics Data System (ADS)

    Kumar, P. V.; Maroncelli, M.

    2000-03-01

    Simulations of the time-dependent friction controlling rotational, translational, and vibrational motions of dipolar diatomic solutes in acetonitrile and methanol have been used to examine the nature of "dielectric" friction. The way in which electrical interactions increase the friction beyond that present in nonpolar systems is found to be rather different than what is anticipated by most theories of dielectric friction. Long-range electrostatic forces do not simply add an independent contribution to the friction due to short-ranged or "mechanical" sources (modeled here in terms of Lennard-Jones forces). Rather, the electrical and Lennard-Jones contributions are found to be strongly anticorrelated and not separable in any useful way. For some purposes, the mechanism by which electrical interactions increase friction is better viewed as a static electrostriction effect: electrical forces cause a subtle increase in atomic density in the solute's first solvation shell, which increases the amplitude of the force fluctuations derived from the Lennard-Jones interactions, i.e., the mechanical friction. However, electrical interactions also modify the dynamics of the friction, typically adding a long-time tail, which significantly increases the integral friction. Both of these effects must be included in a correct description of friction in the presence of polar interactions.

  7. Enlightening discriminative network functional modules behind Principal Component Analysis separation in differential-omic science studies.

    PubMed

    Ciucci, Sara; Ge, Yan; Durán, Claudio; Palladini, Alessandra; Jiménez-Jiménez, Víctor; Martínez-Sánchez, Luisa María; Wang, Yuting; Sales, Susanne; Shevchenko, Andrej; Poser, Steven W; Herbig, Maik; Otto, Oliver; Androutsellis-Theotokis, Andreas; Guck, Jochen; Gerl, Mathias J; Cannistraci, Carlo Vittorio

    2017-03-13

    Omic science is rapidly growing and one of the most employed techniques to explore differential patterns in omic datasets is principal component analysis (PCA). However, a method to enlighten the network of omic features that mostly contribute to the sample separation obtained by PCA is missing. An alternative is to build correlation networks between univariately-selected significant omic features, but this neglects the multivariate unsupervised feature compression responsible for the PCA sample segregation. Biologists and medical researchers often prefer effective methods that offer an immediate interpretation to complicated algorithms that in principle promise an improvement but in practice are difficult to be applied and interpreted. Here we present PC-corr: a simple algorithm that associates to any PCA segregation a discriminative network of features. Such network can be inspected in search of functional modules useful in the definition of combinatorial and multiscale biomarkers from multifaceted omic data in systems and precision biomedicine. We offer proofs of PC-corr efficacy on lipidomic, metagenomic, developmental genomic, population genetic, cancer promoteromic and cancer stem-cell mechanomic data. Finally, PC-corr is a general functional network inference approach that can be easily adopted for big data exploration in computer science and analysis of complex systems in physics.

  8. Pulse laser-induced particle separation from polymethyl methacrylate: a mechanistic study

    NASA Astrophysics Data System (ADS)

    Arif, S.; Armbruster, O.; Kautek, W.

    2013-04-01

    The separation mechanism of opaque and transparent model micro-particles, graphite and polystyrene copolymer spheres, respectively, from polymethyl methacrylate (PMMA) substrates were investigated employing a ns-pulse laser radiating at 532 nm. The particles transparent in the visible wavelength range could be removed from PMMA efficiently in a very narrow fluence range between 1 and 2 J/cm2 according to a simple 1D thermal expansion model. Above this fluence region, with single pulses, the transparent microspheres caused local ablation of the PMMA substrate in the optical microlens nearfield. This process led to removal of the particles themselves due to the expansion of the ablation plasma. The irregularly shaped graphite particles shaded the underlying substrate from the incoming radiation so that no optical nearfield damage mechanism could be observed. Therefore, a substantial cleaning window between 0.5 and more than 16 J/cm2 was provided. The graphite data suggest an ablation mechanism of the particulates themselves due to a high optical absorption coefficient.

  9. Numerical studies on the separation performance of liquid- liquid Hydrocyclone for higher water-cut wells

    NASA Astrophysics Data System (ADS)

    Osei, H.; Al-Kayiem, H. H.; Hashim, F. M.

    2015-12-01

    Liquid-liquid hydrocyclones have nowadays become very useful in the oil industry because of their numerous applications. They can be installed downhole in the case of a well that produces higher water-oil ratios. The design of a liquid-liquid hydrocyclone for such a task is critical and every geometric part of the hydrocyclone has a part to play as far as separation is concerned. This work, through validated numerical technique, investigated the liquid-liquid hydrocyclone performance for the cases of single-inlet and dual-inlets, with different upper cylindrical lengths, specifically, 30mm and 60mm.It was observed that the hydrocyclones with the 30mm upper cylindrical section perform better than the ones with 60 mm upper cylindrical section. It was again noted that, even though higher number of tangential inlets increases the swirl intensity, they have the tendency to break up the oil droplets within the hydrocyclone because of increasing shear and jet flow interaction.

  10. A computational study of saddle point separation and horseshoe vortex system

    NASA Technical Reports Server (NTRS)

    Kaul, U. K.; Kwak, D.; Wagner, C.

    1985-01-01

    Incompressible flow around a cylinder-end wall junction has been simulated by solving the incompressible Navier-Stokes equations in three dimensions. The equations, cast in generalized curvilinear coordinates, are solved in time as a hyperbolic system by adding a pressure term in the continuity equation and are marched to a steady state. Various physical quantities associated with the saddle point of separation and the horseshoe vortex system are calculated. Computational and experimental results are generally consistent. The skin friction and the pressure distribution on the end wall are consistent with the physics of the problem. Secondary flows both in front of the cylinder and behind it are predicted that are in qualitative agreement with flow visualization results. The calculations also indicate a strongly nonuniform pressure loading along the length of the cylinder. A new mechanism for the existence of the recirculation bubbles behind the cylinder-end wall with relatively low ratio of cylinder height to the approaching boundary layer thickness is observed which is markedly different from its two-dimensional counterpart.

  11. Enlightening discriminative network functional modules behind Principal Component Analysis separation in differential-omic science studies

    PubMed Central

    Ciucci, Sara; Ge, Yan; Durán, Claudio; Palladini, Alessandra; Jiménez-Jiménez, Víctor; Martínez-Sánchez, Luisa María; Wang, Yuting; Sales, Susanne; Shevchenko, Andrej; Poser, Steven W.; Herbig, Maik; Otto, Oliver; Androutsellis-Theotokis, Andreas; Guck, Jochen; Gerl, Mathias J.; Cannistraci, Carlo Vittorio

    2017-01-01

    Omic science is rapidly growing and one of the most employed techniques to explore differential patterns in omic datasets is principal component analysis (PCA). However, a method to enlighten the network of omic features that mostly contribute to the sample separation obtained by PCA is missing. An alternative is to build correlation networks between univariately-selected significant omic features, but this neglects the multivariate unsupervised feature compression responsible for the PCA sample segregation. Biologists and medical researchers often prefer effective methods that offer an immediate interpretation to complicated algorithms that in principle promise an improvement but in practice are difficult to be applied and interpreted. Here we present PC-corr: a simple algorithm that associates to any PCA segregation a discriminative network of features. Such network can be inspected in search of functional modules useful in the definition of combinatorial and multiscale biomarkers from multifaceted omic data in systems and precision biomedicine. We offer proofs of PC-corr efficacy on lipidomic, metagenomic, developmental genomic, population genetic, cancer promoteromic and cancer stem-cell mechanomic data. Finally, PC-corr is a general functional network inference approach that can be easily adopted for big data exploration in computer science and analysis of complex systems in physics. PMID:28287094

  12. Studies of light scattering and morphologies of phase-separated polymer/nanoparticle mixtures

    NASA Astrophysics Data System (ADS)

    Ding, Xuan

    Nowadays, solid "filler" particles can be found in many manufactured polymeric materials because of the enhanced thermal and mechanical properties these particles can offer. However, the influence of the "filler" particles, especially those with size on a nanoscopic scale, on the structural evolution of multicomponent systems, is still poorly understood. In this thesis, the spinodal decomposition (SD) of polystyrene/poly(vinyl methyl ether) (PS/PVME) polymer blend system mixed with different nanoparticles have been investigated by the small angle light scattering (SALS) technique. Interpreting the data using the Cahn-Hilliard linear theory and the scaling theory on early stage and late stage, respectively, we concluded that the addition of nanoparticles into the pure polymer blends can cause a retardation of the phase separation. Furthermore, experiments on polystyrene/poly(2-vinyl pyridine) (PS/P2VP) polymer blends mixed with polystyrene-covered gold nanoparticles (Au-PS) have shown that during the spinodal decomposition these Au-PS nanoparticles can self-assemble at the continuous PS/P2VP interface, due to the tendency to reduce interfacial energy, making it possible to create the so-called "bijel" structure (bicontinuous interfacially jammed emulsion jel). We believe that the "bijel" structures have a huge potential of being used in areas such as photovoltaics and catalysis, because of their large surface areas.

  13. Stereoisomers Separation

    NASA Astrophysics Data System (ADS)

    Wieczorek, Piotr

    The use of capillary electrophoresis for enantiomer separation and optical purity determination is presented. The contents start with basic information about the nature of stereoizomers and the mechanism of enantioseparation using capillary electrophoresis techniques. The molecules to be separated show identical chemical structure and electrochemical behavior. Therefore, the chiral recognition of enantiomers is possible only by bonding to chiral selector and the separation based on very small differences in complexation energies of diastereomer complexes formed. This method is useful for this purpose due to the fact that different compounds can be used as chiral selectors. The mostly used chiral selectors like cyclodextrins, crown ethers, chiral surfactants, macrocyclic antibiotics, transition metal complexes, natural, and synthetic polymers and their application for this purpose is also discussed. Finally, examples of practical applications of electromigration techniques for enantiomers separation and determination are presented.

  14. Mist separator

    SciTech Connect

    Moran, T.M.

    1984-04-17

    An apparatus for the removal of particulates from a flowing gas stream and a process for its use are provided. A perforated screen separator formed as a plate having parallel rows of perforations formed by pushing alternating strips of the plate material forward and backward from the plane of the plate is used. The perforated screen separator may be used alone or with a fiber bed mist eliminator for increased particulate removal.

  15. WRAP Module 1 sampling strategy and waste characterization alternatives study

    SciTech Connect

    Bergeson, C.L.

    1994-09-30

    The Waste Receiving and Processing Module 1 Facility is designed to examine, process, certify, and ship drums and boxes of solid wastes that have a surface dose equivalent of less than 200 mrem/h. These wastes will include low-level and transuranic wastes that are retrievably stored in the 200 Area burial grounds and facilities in addition to newly generated wastes. Certification of retrievably stored wastes processing in WRAP 1 is required to meet the waste acceptance criteria for onsite treatment and disposal of low-level waste and mixed low-level waste and the Waste Isolation Pilot Plant Waste Acceptance Criteria for the disposal of TRU waste. In addition, these wastes will need to be certified for packaging in TRUPACT-II shipping containers. Characterization of the retrievably stored waste is needed to support the certification process. Characterization data will be obtained from historical records, process knowledge, nondestructive examination nondestructive assay, visual inspection of the waste, head-gas sampling, and analysis of samples taken from the waste containers. Sample characterization refers to the method or methods that are used to test waste samples for specific analytes. The focus of this study is the sample characterization needed to accurately identify the hazardous and radioactive constituents present in the retrieved wastes that will be processed in WRAP 1. In addition, some sampling and characterization will be required to support NDA calculations and to provide an over-check for the characterization of newly generated wastes. This study results in the baseline definition of WRAP 1 sampling and analysis requirements and identifies alternative methods to meet these requirements in an efficient and economical manner.

  16. Product separator

    DOEpatents

    Welsh, Robert A.; Deurbrouck, Albert W.

    1976-01-20

    A secondary light sensitive photoelectric product separator for use with a primary product separator that concentrates a material so that it is visually distinguishable from adjacent materials. The concentrate separation is accomplished first by feeding the material onto a vibratory inclined surface with a liquid flow, such as a wet concentrating table. Vibrations generally perpendicular to the stream direction of flow cause the concentrate to separate from its mixture according to its color. When the concentrate and its surrounding stream reach the recovery end of the table, a detecting device notes the line of color demarcation and triggers a signal if it differs from a normal condition. If no difference is noted nothing moves on the second separator. However, if a difference is detected in the constant monitoring of the color line's location, a product splitter and recovery unit normally positioned near the color line at the recovery end, moves to a new position. In this manner the selected separated concentrate is recovered at a maximum rate regardless of variations in the flow stream or other conditions present.

  17. Diffusion and Defect Characterization Studies of Mercury Cadmium Telluride

    DTIC Science & Technology

    1989-08-01

    Mercury Cadmium Telluride" Principal Investigator: D. A. Stevenson Department of Materials Science and Engineering Stanford University Stanford, CA 94305...Include Security Classificatton, Difuson Defect Characterization Studies of Mercury Cadmium Telluride 12 PERSONAL AUTHOR(S) ProfessJL Ddvid A. Stevenson 13a...diffusion and defect chemistry of mercury cadmium telluride (MCT; Hg Cd Te). In this study, we have measured tracer self- diffusion and interdiffusion

  18. Bad split during bilateral sagittal split osteotomy of the mandible with separators: a retrospective study of 427 patients.

    PubMed

    Mensink, Gertjan; Verweij, Jop P; Frank, Michael D; Eelco Bergsma, J; Richard van Merkesteyn, J P

    2013-09-01

    An unfavourable fracture, known as a bad split, is a common operative complication in bilateral sagittal split osteotomy (BSSO). The reported incidence ranges from 0.5 to 5.5%/site. Since 1994 we have used sagittal splitters and separators instead of chisels for BSSO in our clinic in an attempt to prevent postoperative hypoaesthesia. Theoretically an increased percentage of bad splits could be expected with this technique. In this retrospective study we aimed to find out the incidence of bad splits associated with BSSO done with splitters and separators. We also assessed the risk factors for bad splits. The study group comprised 427 consecutive patients among whom the incidence of bad splits was 2.0%/site, which is well within the reported range. The only predictive factor for a bad split was the removal of third molars at the same time as BSSO. There was no significant association between bad splits and age, sex, class of occlusion, or the experience of the surgeon. We think that doing a BSSO with splitters and separators instead of chisels does not increase the risk of a bad split, and is therefore safe with predictable results.

  19. Numerical study of the primary instability in a separated boundary layer transition under elevated free-stream turbulence

    NASA Astrophysics Data System (ADS)

    Langari, Mostafa; Yang, Zhiyin

    2013-07-01

    Numerical studies of laminar-to-turbulent transition in a separation bubble subjected to two free-stream turbulence levels (FST) have been performed using Large-Eddy Simulation (LES). Separation of the laminar boundary layer occurs at a curvature change over a plate with a semi-circular leading edge at Re = 3450 based on the plate thickness and the uniform inlet velocity. A numerical trip is used to produce the targeted free-stream turbulence levels and the decay of free-stream turbulence is well predicted. A dynamic sub-grid-scale model is employed in the current study and a good agreement has been obtained between the LES results and the experimental data. Detailed analysis of the LES data has been carried out to investigate the primary instability mechanism. The flow visualisations and spectral analysis of the separated shear layer reveal that the 2D Kelvin-Helmholtz instability mode, well known to occur at low FST levels, is bypassed at higher levels leading to earlier breakdown to turbulence.

  20. A study of multistage/multifunction column for fine particle separation. Quarterly report, 1 October 1995--31 December 1995

    SciTech Connect

    Chiang, Shiao-Hung; Lai, Ralph W.

    1996-01-20

    The overall purpose of the proposed research program is to explore the potential application of a new invention involving a multistage column equipped with vortex-inducing loop-flow contactors hereafter referred to as (bold the multistage column) for fine coal cleaning process. The research work will identify the design parameters and their effects on the performance of the separation process. The results of this study will provide an engineering basis for further development of this technology in coal cleaning and in the general areas of fluid/particle separation. In the last quarter, the (bold bubble size) measurements were carried out in the conventional column. Also, correlations were developed for results on (bold gas holdup, bubble size and specific interfacial area). In this quarter, we investigated the mixing and loop flow (circulation) behaviors around the contactor.

  1. Characterization of flavonoid glycosides from rapeseed bee pollen using a combination of chromatography, spectrometry and nuclear magnetic resonance with a step-wise separation strategy.

    PubMed

    Li, Yi; Qi, Yitao; Ritho, Joan; Zhang, Yongxin; Zheng, Xiaowei; Zhou, Jinhui; Sun, Liping

    2016-01-01

    To identify the structures of flavonoid glycosides in bee pollen collected from rapeseed plants (Brassica napus L.), we utilised an approach that combined liquid chromatography-diode array detector-electrospray ionization-mass spectrometry (LC-DAD-ESI-MS) and nuclear magnetic resonance (NMR) technology with a step-wise separation strategy. We identified four constituents of high purity in rape bee pollen samples: (1) quercetin-3-O-β-D-glucosyl-(2→l)-β-glucoside, (2) kaempferol-3, 4'-di-O-β-D-glucoside, (3) 5, 7, 4'-trihydroxy-3'-methoxyflavone-3-O-β-D-sophoroside and (4) kaempferol-3-O-β-D-glucosyl-(2→l)-β-D-glucoside. This study will also provide useful reference standards for qualification and quantification of four flavonoid glycosides in natural products.

  2. Remote gate capacitance-voltage studies for noninvasive surface characterization

    NASA Technical Reports Server (NTRS)

    Chang, R. R.; Lile, D. L.; Gann, R.

    1987-01-01

    A measurement technique has been developed which allows noncontact capacitance-voltage measurements to be made using a gate electrode located remote from the semiconductor surface under study. With gate electrodes about 0.5 mm in diameter and gate to semiconductor separations of about 1500 A, it was possible to generate data entirely comparable to that obtained with integrated MIS structures but with the advantage that there was access directly to the free-semiconductor surface. This technique was applied to bulk single-crystal Si and InP samples.

  3. Separating the Wheat from the Chaff in Middle School Literature Study Guides.

    ERIC Educational Resources Information Center

    Radencich, Marguerite Cogorno

    1997-01-01

    Describes and discusses an evaluation procedure for middle school literature study guides that uses a combination of three frameworks: J. Langer's model of literature study, H. Gardner's theory of multiple intelligences, and B. Cambourne's conditions for learning. Uses the evaluation procedure to compare two study guides for a historical fiction…

  4. Characterization of a solvent-separated ion-radical pair in cationized water networks: infrared photodissociation and Ar-attachment experiments for water cluster radical cations (H2O)n+(n = 3-8).

    PubMed

    Mizuse, Kenta; Fujii, Asuka

    2013-02-07

    We present infrared spectra of nominal water cluster radical cations (H(2)O)(n)(+) (n = 3-8), or to be precise, ion-radical complexes H(+)(H(2)O)(n-1)(OH), with and without an Ar tag. These clusters are closely related to the ionizing radiation-induced processes in water and are a good model to characterize solvation structures of the ion-radical pair. The spectra of Ar-tagged species show narrower bandwidths relative to those of the bare clusters due to the reduced internal energy via an Ar-attachment. The observed spectra are analyzed by comparing with those of the similar system, H(+)(H(2)O)(n), and calculated ones. We find that the observed spectra are attributable to ion-radical-separated motifs in n ≥ 5, as reported in the previous study (Mizuse et al. Chem. Sci.2011, 2, 868-876). Beyond the structural trends found in the previous study, we characterize isomeric structures and determine the number of water molecules between the charged site and the OH radical in each cluster size. In all of the characterized cluster structures (n = 5-8), the most favorable position of OH radical is the next neighbor of the charged site (H(3)O(+) or H(5)O(2)(+)). The positions and cluster structures are governed by the balance among the hydrogen-bonding abilities of the charged site, H(2)O, and OH radical. These findings on the ionized water networks lead to understanding of the detailed processes of ionizing radiation-initiated reactions in liquid water and aqueous solutions.

  5. Separation of epidermal cells by density centrifugation: a new technique for studies on normal and pathological differentiation.

    PubMed

    Fischer, S M; Nelson, K D; Reiners, J J; Viaje, A; Pelling, J C; Slaga, T J

    1982-02-01

    Murine keratinocytes, isolated by flotation trypsinization of skin, can be separated into five groups by centrifugation through Percoll, a colloidal silica gradient. Within each group a good correlation was found between density, plating efficiency, morphological appearance, DNA synthesis, and degree of keratinization/cornification. This method can be applied equally well to fetal, newborn, or adult keratinocytes and should be useful in a variety of studies including isolation of subpopulations of pathological cell types, work on chalones and hyperplastic diseases such as psoriasis, and in vitro transformation studies.

  6. TDDFT study of the polarity controlled ion-pair separation in an excited-state proton transfer reaction.

    PubMed

    Liu, Yu-Hui; Mehata, Mohan Singh; Lan, Sheng-Cheng

    2014-07-15

    6-Hydroxyquinoline (6HQ) is an ideal photoacid system for exploring excited-state proton transfer (ESPT) reactions. We have previously (Mahata et al. (2002)) shown that the ESPT reaction between 6HQ and trimethylamine (TMA) leads to an "unusual" emission in the 440-450 nm range, containing two decay components (∼5 ns and ∼12 ns). The observed results suggest the presence of a contact ion-pair and a solvent separated ion-pair. In this work, density functional theory (DFT) and time-dependent density functional theory (TD-DFT) have been employed to study the nature of the contact ion-pair formed between 6HQ and TMA and to determine why the decay component ∼12 ns is absent in a non-polar solvent. Calculations of the hydrogen-bonded complexes formed between 6HQ and TMA and its ESPT reaction product, namely 6HQ-TMA and 6HQ-TMA-PT, respectively, have been carried out, both in the electronic ground and excited states. Moreover, by using the CPCM model, different dielectric constants have been introduced into the calculations. On increasing the dielectric constant, the hydrogen bond in 6HQ-TMA-PT becomes weaker and the hydrogen bond length becomes larger; this effectively facilitates the proton transfer reaction and formation of separated ion-pair. Thus, the separation and diffusion of the contact ion-pair can be controlled by changing the polarity of the surroundings.

  7. Numerical study on the effect of charge separation at low cloud temperature and effective water content on thunderstorm electrification

    NASA Astrophysics Data System (ADS)

    Tsenova, Boryana Dimitrova; Barakova, Denitsa; Mitzeva, Rumjana

    2017-02-01

    In the present study, a numerical model is used to evaluate the effects of low effective water content and low cloud temperature on graupel charging, charge structure and lightning activity in regions of thunderstorms. Two idealized cloud cases were simulated with MesoNH using different configurations of the main known parameterizations for noninductive charging involving ice crystal/graupel rebounding collisions. Simulations in regions with very low effective cloud water content were performed with the parameterization proposed in Mitzeva et al. (2006) based on the "Relative Growth Rate" hypothesis, while for simulations in regions with low cloud temperature, charge values from Avila et al. (2011) were used. Results showed that the inclusion of the charge separation at very low effective water content influences more the simulated cloud charge structure than does the inclusion of the charge separated at low temperatures. Also, the effect of the charge separated at very low effective water content is more significant when the original parameterization for non-inductive charging is based on the effective water content rather than on the rime accretion rate.

  8. High-performance reversed-phase ion-pair chromatographic study of myo-inositol phosphates. Separation of myo-inositol phosphates, some common nucleotides and sugar phosphates.

    PubMed

    Patthy, M; Balla, T; Arányi, P

    1990-12-07

    A detailed study of all the major chromatographic variables affecting the retention behaviour and separation of myo-inositol phosphates in reversed-phase ion-pair chromatographic systems was carried out. The parameters studied included the eluent concentration of the pairing ion, the eluent concentration of the organic modifier and the buffer salt, the pH of the eluent, the minimum column plate count necessary for the separation of the inositol trisphosphate isomers and isocratic and gradient modes of separation. The retention behaviour of some common nucleotides and sugar phosphates was also investigated as these phosphates present chromatographic interference problems in biochemical studies based on the cellular incorporation of [32P]Pi. The separation methods developed appear to be superior to established anion-exchange separation techniques in terms of separation speed and "mildness" of the chromatographic conditions.

  9. Dissection of the gene of the bifunctional PGK-TIM fusion protein from the hyperthermophilic bacterium Thermotoga maritima: design and characterization of the separate triosephosphate isomerase.

    PubMed Central

    Beaucamp, N.; Hofmann, A.; Kellerer, B.; Jaenicke, R.

    1997-01-01

    Triosephosphate isomerase (TIM), from the hyperthermophilic bacterium Thermotoga maritima, has been shown to be covalently linked to phosphoglycerate kinase (PGK) forming a bifunctional fusion protein with TIM as the C-terminal portion of the subunits of the tetrameric protein (Schurig et al., EMBO J 14:442-451, 1995). To study the effect of the anomalous state of association on the structure, stability, and function of Thermotoga TIM, the isolated enzyme was cloned and expressed in Escherichia coli, and compared with its wild-type structure in the PGK-TIM fusion protein. After introducing a start codon at the beginning of the tpi open reading frame, the gene was expressed in E.c.BL21(DE3)/ pNBTIM. The nucleotide sequence was confirmed and the protein purified as a functional dimer of 56.5 kDa molecular mass. Spectral analysis, using absorption, fluorescence emission, near- and far-UV circular dichroism spectroscopy were used to compare the separated Thermotoga enzyme with its homologs from mesophiles. The catalytic properties of the enzyme at approximately 80 degrees C are similar to those of its mesophilic counterparts at their respective physiological temperatures, in accordance with the idea that under in vivo conditions enzymes occupy corresponding states. As taken from chaotropic and thermal denaturation transitions, the separated enzyme exhibits high intrinsic stability, with a half-concentration of guanidinium-chloride at 3.8 M, and a denaturation half-time at 80 degrees C of 2 h. Comparing the properties of the TIM portion of the PGK-TIM fusion protein with those of the isolated recombinant TIM, it is found that the fusion of the two enzymes not only enhances the intrinsic stability of TIM but also its catalytic efficiency. PMID:9336838

  10. Characterization and degradation studies on synthetic polymers for aerospace application

    NASA Technical Reports Server (NTRS)

    Hsu, M. T. S.

    1982-01-01

    The anti-misting additive for jet fuels known as FM-9 (proprietary polymer) was characterized by elemental analysis, solubility studies and molecular weight determination. Physical properties of surface tension, viscosity, specific gravity and other physical parameters were determined. These results are compared with properties of polyisobutylene and fuels modified with the same; the misting characteristics of polyisobutylene and FM-9 in Jet A fuel are included. Characterization and degradation of phthalocyanine and its derivatives were accomplished by use of a mass spectrometer and a pyroprobe solid pyrolyzer. Metal phthalocyanine tetracarboxylic acids and phthalocyanine-tetraamine cured epoxies were studied. Epoxy/graphite composite panels were exposed to a NASA-Ames radiant panel fire simulator in the flaming and non-flaming modes; toxic gases of HCN and HZS were measured along with oxygen, Co2, Co, and organic gases.

  11. ISOTOPE SEPARATORS

    DOEpatents

    Bacon, C.G.

    1958-08-26

    An improvement is presented in the structure of an isotope separation apparatus and, in particular, is concerned with a magnetically operated shutter associated with a window which is provided for the purpose of enabling the operator to view the processes going on within the interior of the apparatus. The shutier is mounted to close under the force of gravity in the absence of any other force. By closing an electrical circuit to a coil mouated on the shutter the magnetic field of the isotope separating apparatus coacts with the magnetic field of the coil to force the shutter to the open position.

  12. Isotope separation

    DOEpatents

    Bartlett, Rodney J.; Morrey, John R.

    1978-01-01

    A method and apparatus is described for separating gas molecules containing one isotope of an element from gas molecules containing other isotopes of the same element in which all of the molecules of the gas are at the same electronic state in their ground state. Gas molecules in a gas stream containing one of the isotopes are selectively excited to a different electronic state while leaving the other gas molecules in their original ground state. Gas molecules containing one of the isotopes are then deflected from the other gas molecules in the stream and thus physically separated.

  13. Growth And Characterization Studies Of Advanced Infrared Heterostructures

    DTIC Science & Technology

    2015-06-30

    Research Laboratory AFRL /RVSS Space Vehicles Directorate 3550 Aberdeen Ave., SE 11. SPONSOR/MONITOR’S REPORT Kirtland AFB, NM 87117-5776 NUMBER(S... Kirtland AFB, NM 87117-5776 2 cys Official Record Copy AFRL /RVSS/Christian Morath 1 cy ... AFRL -RV-PS- TR-2015-0126 AFRL -RV-PS- TR-2015-0126 GROWTH AND CHARACTERIZATION STUDIES OF ADVANCED INFRARED HETEROSTRUCTURES Sanjay Krishna

  14. Mechanistic Studies Of Combustion And Structure Formation During Combustion Synthesis Of Advanced Materials: Phase Separation Mechanism For Bio-Alloys

    NASA Technical Reports Server (NTRS)

    Varma, A.; Lau, C.; Mukasyan, A.

    2003-01-01

    Among all implant materials, Co-Cr-Mo alloys demonstrate perhaps the most useful balance of resistance to corrosion, fatigue and wear, along with strength and biocompatibility [1]. Currently, these widely used alloys are produced by conventional furnace technology. Owing to high melting points of the main alloy elements (e.g. Tm.p.(Co) 1768 K), high-temperature furnaces and long process times (several hours) are required. Therefore, attempts to develop more efficient and flexible methods for production of such alloys with superior properties are of great interest. The synthesis of materials using combustion phenomena is an advanced approach in powder metallurgy [2]. The process is characterized by unique conditions involving extremely fast heating rates (up to 10(exp 6 K/s), high temperatures (up to 3500 K), and short reaction times (on the order of seconds). As a result, combustion synthesis (CS) offers several attractive advantages over conventional metallurgical processing and alloy development technologies. The foremost is that solely the heat of chemical reaction (instead of an external source) supplies the energy for the synthesis. Also, simple equipment, rather than energy-intensive high-temperature furnaces, is sufficient. This work was devoted to experiments on CS of Co-based alloys by utilizing thermite (metal oxide-reducing metal) reactions, where phase separation subsequently produces materials with tailored compositions and properties. Owing to high reaction exothermicity, the CS process results in a significant increase of temperature (up to 3000 C), which is higher than melting points of all products. Since the products differ in density, phase separation may be a gravitydriven process: the heavy (metallic phase) settles while the light (slag) phase floats. The goal was to determine if buoyancy is indeed the major mechanism that controls phase segregation.

  15. Y-12 old salvage yard scrap metal characterization study

    SciTech Connect

    Anderson, L.M.; Melton, S.G.; Shaw, S.S.

    1993-11-01

    The purpose of the Y-12 Old Salvage Yard scrap metal Characterization Study is to make conservative estimates of the quantities of total uranium and the wt % {sup 235}U contained in scrap metal. The original project scope included estimates of thorium, but due to the insignificant quantities found in the yards, thorium was excluded from further analysis. Metal in three of the four Y-12 scrap metal yards were characterized. The scrap metal yard east of the PIDAS fence is managed by the Environmental Restoration Program and therefore was not included in this study. For all Y-12 Plant scrap metal shipments, Waste Transportation, Storage, and Disposal (WTSD) personnel must complete a Request for Authorization to Ship Nuclear Materials, UCN-16409, which requires the grams of total uranium, the wt % {sup 235}U, and the grams of {sup 235}U contained in the shipment. This information is necessary to ensure compliance with Department of Transportation regulations, as well as to ensure that the receiving facility is adhering to its operating license. This characterization study was designed to provide a technical basis for determining these necessary radioactive quantities.

  16. Wilsonville SRC-I pilot plant: I. Fractionation area corrosion studies; II. Hot vs. normal separation mode of operation

    SciTech Connect

    Lee, J.M.

    1981-04-01

    Extensive corrosion studies in solvent recovery columns have been done with different coals (mainly Kentucky number 9 Lafayette, Dotiki and Fies). Sodium carbonate (0.1 to 1.1% of coal) was added as neutralizer to control corrosion rate. Chloride balance runs were made for isolation of corrosive streams with high chlorine content. A caustic wash program of inlet streams has been developed for selective treatment of corrosive streams as an alternative means for possible replacement of sodium carbonate addition. High chlorine content coals such as Kentucky number 9 Lafayette and Dotiki (0.2 to 0.3%) were very corrosive, compared to low chlorine content coal, Kentucky number 9 Fies (< 0.1%). Sodium carbonate addition (0.6 to 0.7% of coal) reduced corrosion rate from 500 MPY to an insignificant level of less than 5 MPY. Caustic wash of solvents could reduce corrosion rate by 50%, removing most corrosive compounds present in the 440 to 480/sup 0/F boiling fraction. Extensive studies for the hot separator mode of operation have been done as a means of saving substantial energy by elimination of dissolver slurry cooling (0.3 MM Btu/hr) and reheating for solvent recovery (1 MM Btu/h). Impacts of the hot separator mode on plant operability, product quality and Kerr-McGee CSD Unit recovery have been studied. The hot separator mode of operation was carried out by controlling the V103 temperature to 740/sup 0/F. It was observed that preasphaltene contents increased in the SRC products such as V110 L/F SRC and CSD feed; CSD unit recovery was not affected significantly; solvent quality was not affected significantly.

  17. A fine coal circuitry study using column flotation and gravity separation. Quarterly report, 1 December 1994--28 February 1995

    SciTech Connect

    Honaker, R.Q.; Reed, S.

    1995-12-31

    Column flotation provides excellent recovery of ultrafine coal while producing low ash content concentrates. However, column flotation is not efficient for treating fine coal containing significant amounts of mixed-phase particles. Fortunately, enhanced gravity separation has proved to have the ability to treat the mixed-phased particles more effectively. A disadvantage of gravity separation is that ultrafine clay particles are not easily rejected. Thus, a combination of these two technologies may provide a circuit that maximizes both the ash and sulfur rejection that can be achieved by physical coal cleaning while maintaining a high energy recovery. This project is studying the potential of using different combinations of gravity separators, i.e., a Floatex hydrosizer and a Falcon Concentrator, and a proven flotation column, which will be selected based on previous studies by the principle investigator. During this reporting period, an in-plant Box-Behnken test program of the Floatex hydrosizer has been conducted at Kerr-McGee`s Galatia preparation plant. The results have shown that the Floatex hydrosizer can be successfully used to reject most of coarser ({plus}100 mesh) pyrite and mineral matter in the coal stream to the plant. With a single operation, ash rejection of 63% and total sulfur rejection of 43% have been achieved while maintaining a combustible recovery as high as 90.5%. A long term duration test under the optimum operating conditions determined from Box-Behnken test results has also been conducted. The feed samples for the following enhanced gravity - column flotation studies, which will be carried out in the next reporting period, have been collected.

  18. An evaporation study for phthalic acids--a rapid method for pharmaceutical characterization.

    PubMed

    Chatterjee, Koustuv; Hazra, Anasuya; Dollimore, David; Alexander, Kenneth S

    2002-04-01

    The objective of this study was to develop and analyze an analytical method in order to evaluate preformulation candidates by their thermodynamic parameters and evaporation characteristics. Ortho, meta and tere-phthalic acids were chosen as model compounds. The relative advantages and disadvantages of a rapid thermogravimetric method have been studied in detail, which would aid in the preformulation characterization for pharmaceuticals. Methyl paraben was taken as the model compound for calibration, as its evaporation characteristics are well known. Using the Antoine and the Langmuir equation for evaporation conjointly, the parameter k, known as the coefficient of evaporation was determined. The value for this constant was validated by three methods simultaneously. Previously the use of such methods for compounds having uninhibited zero order evaporation has been documented. In the present study, phthalic acid was chosen as the model compound since its evaporation is a two-step overlapping phenomenon. In this study we have shown the use of Pressure Differential Scanning Calorimetry in separating such simultaneous endothermic processes. The Clausius-Clapeyron equation seemingly has anomalous behavior for vapor pressure over high temperature ranges. In this study a modification of the equation has been suggested to take into account the changes in the heat capacities that result due to high temperature effects. This study aims at documenting a concise method for rapid pharmaceutical characterization and suggests modifications for some basic thermodynamic parameters over higher temperature ranges.

  19. Generation and collection of restaurant waste: Characterization and evaluation at a case study in Italy.

    PubMed

    Tatàno, Fabio; Caramiello, Cristina; Paolini, Tonino; Tripolone, Luca

    2017-03-01

    Because restaurants (as a division of the hospitality sector) contribute to the generation of commercial and institutional waste, thus representing both a challenge and an opportunity, the objective of the present study was to deepen the knowledge of restaurant waste in terms of the qualitative and quantitative characteristics of waste generation and the performance achievable by the implementation of a separate collection scheme. In this study, the generated waste was characterized and the implemented separate collection was evaluated at a relevant case study restaurant in a coastal tourist area of Central Italy (Marche Region, Adriatic Sea side). The qualitative (compositional) characterization of the generated total restaurant waste showed considerable incidences of, in decreasing order, food (28.2%), glass (22.6%), paper/cardboard (19.1%), and plastic (17.1%). The quantitative (parametric) characterization of the generated restaurant waste determined the unit generation values of total waste and individual fractions based on the traditional employee and area parameters and the peculiar meal parameter. In particular, the obtained representative values per meal were: 0.72kgmeal(-1) for total waste, and ranging, for individual fractions, from 0.20 (for food) to 0.008kgmeal(-1) (for textile). Based on the critical evaluation of some of the resulting unit waste generation values, possible influences of restaurant practices, conditions, or characteristics were pointed out. In particular, food waste generation per meal can likely be limited by: promoting and using local, fresh, and quality food; standardizing and limiting daily menu items; basing food recipes on consolidated cooking knowledge and experience; and limiting plate sizes. The evaluation of the monthly variation of the monitored separate collection, ranging from an higher level of 52.7% to a lower level of 41.4%, indicated the following: a reduction in the separate collection level can be expected at times

  20. Separate but equal? A system comparison study of MEDLINE's controlled vocabulary MeSH.

    PubMed Central

    Hallett, K S

    1998-01-01

    This study tested the effect of controlled vocabulary search feature implementation on two online systems. Specifically, the study examined retrieval rates using four unique controlled vocabulary search features (explode, major descriptor, descriptor, subheadings). Each search feature was applied to nine search queries obtained from a medical reference librarian. The same queries were searched in the complete MEDLINE file on the Dialog and Ovid systems. The unique records, i.e., those records retrieved in only one of the two systems, were identified and analyzed. Dialog produced equal or more records than Ovid in nearly 20% of the queries. The study demonstrated that users need to be aware of system-specific designs that may require differing input strategies across different systems for the same unique controlled vocabulary search features. The paper concludes by making recommendations and suggestions for future research. PMID:9803290

  1. Fundamental studies of carbon-based nanomaterials: Exploring the interface between nanotechnology and separation science

    NASA Astrophysics Data System (ADS)

    Vinci, John Cody

    A sample containing carbon nanoparticles (CNPs) was generated starting with the soot from the combustion of inexpensive paraffin oil in a flame. The complexity of the sample, however, required fractionation to isolate its components. Anion-exchange high-performance liquid chromatography (AE-HPLC) was used for the analysis and collection of soot-derived CNPs. The fractionated species were monitored by ultraviolet (UV) absorbance and laser-induced photoluminescence detection, providing the chromatographic UV absorbance and emission profiles of the separated sample. Chromatographic fractionation allowed for bulk measurements of electronic properties for individual fractions, and further analysis via transmission electron microscopy (TEM). TEM of fractionated species showed a predominant size of about 3-5 nm diameter particulates, including carbon dots (C-dots), irregularly-shaped/amorphous CNPs, and graphitic nanoribbons. A general trend between photoluminescence and elution time was observed; the later eluting species in the chromatogram exhibited photoluminescence at longer wavelengths than the early eluting species. Graphite nanofibers were shown to be effective for synthesizing C-dots exclusively but also exist as a relatively complex mixture. An unprecedented reduction in such complexity by AE-HPLC revealed fractions of C-dots with unique photoluminescence properties. The wavelength-dependent photoluminescence commonly assigned as an inherent property of C-dots was not present in fractionated samples. While UV-visible absorption profiles reported for C-dots are typically featureless, fractions of C-dots were found to possess unique absorption bands, with different fractions possessing specific emission wavelengths. Furthermore, fractionated C-dots showed profound differences in emission quantum yield, allowing for brighter C-dots to be isolated from an apparent low quantum yield mixture. These more photoluminescent fractions of C-dots displayed improved

  2. SEPARATION PROCESS

    DOEpatents

    Stoughton, R.W.

    1961-10-24

    A process for separating tetravalent plutonium from aqueous solutions and from niobium and zirconium by precipitation on lanthanum oxalate is described. The oxalate ions of the precipitate may be decomposed by heating in the presence of an oxidizing agent, forming a plutonium compound readily soluble in acid. (AEC)

  3. Plasma separation

    NASA Technical Reports Server (NTRS)

    Steurer, Wolfgang

    1992-01-01

    This process employs a thermal plasma for the separation and production of oxygen and metals. It is a continuous process that requires no consumables and relies entirely on space resources. The almost complete absence of waste renders it relatively clean. It can be turned on or off without any undesirable side effects or residues. The prime disadvantage is its high power consumption.

  4. A study of the dentinal permeability of the pulp chamber floor of human lower molars with separate roots.

    PubMed

    Pécora, J D; Costa, W F; Maia Campos, G

    1990-01-01

    The permeability of the dentin of the pulp chamber floor of lower molars with separate roots was studied, after instrumentation of the root canals by manual or ultrasonic techniques. The dentinal permeability was evaluated by the degree of penetration of copper ions in the tissue and quantified by methods used in morphometry. None of the combinations of irrigating solution/instrumentation technique caused an increase in the permeability of dentinal tissue in the pulp chamber region, probably because the dentin is reparative dentin, which is more amorphous and less tubular than primary dentin.

  5. A rapid means of separating A14-/sup 125/I-insulin from heterogeneously labeled insulin molecules for biologic studies

    SciTech Connect

    Stentz, F.B.; Wright, R.K.; Kitabchi, A.E.

    1982-12-01

    We have used two methods for the preparation of a highly homogeneous insulin with high specific activity. After iodination with chloramine T, the labeled peptides were retained on a disposable Sep Pak cartridge and subsequently eluted. The eluted labeled insulins were further purified by either DEAE cellulose or high performance liquid chromatography (HPLC) to separate A14-/sup 125/I- from A19-/sup 125/I-insulin. Both methods of chromatography were effective, but HPLC offered the advantage of better resolution in less time and higher yields of A14-/sup 125/I-insulin, which is suitable for biologic studies in various target tissues.

  6. Thermodynamic study of characteristics of the converter with separated supply of hydrocarbon fuel for thermo-oxidative and steam reforming

    NASA Astrophysics Data System (ADS)

    Bassina, I. A.; Malkov, Yu. P.; Molchanov, O. N.; Stepanov, S. G.; Troshchinenko, G. A.; Zasypkin, I. M.

    2014-04-01

    Thermodynamic studies of the converter characteristics were performed to produce hydrogen-containing syngas from hydrocarbon fuel (kerosene) with its separated supply for thermo-oxidative and steam reforming. It is demonstrated that the optimal conditions of the converter performance correlate with the oxidant ratio of α > 0.5 at the heattransfer wall temperature of 1200 K. Hydrogen content in the final syngas reaches 60 % by volume, free carbon (soot) deposition in reforming products is excluded, and there is no need to apply walls water cooling in the converter.

  7. Process for phase separation

    DOEpatents

    Comolli, Alfred G.

    1979-01-01

    This invention provides a continuous process for separating a gaseous phase from a hydrocarbon liquid containing carbonaceous particulates and gases. The liquid is fed to a cylindrical separator, with the gaseous phase being removed therefrom as an overhead product, whereas the hydrocarbon liquid and the particulates are withdrawn as a bottoms product. By feeding the liquid tangentially to the separator and maintaining a particulate-liquid slurry downward velocity of from about 0.01 to about 0.25 fps in the separator, a total solids weight percent in the slurry of from about 0.1 to about 30%, a slurry temperature of from about 550.degree. to about 900.degree. F., a slurry residence time in the separator of from about 30 to about 360 seconds, and a length/diameter ratio for the separator of from about 20/1 to about 50/1, so that the characterization factor, .alpha., defined as ##STR1## DOES NOT EXCEED ABOUT 48 (.degree.R sec.sup.2)/ft, the deposit of carbonaceous materials on the interior surface of the separator may be substantially eliminated.

  8. Separate, but Not Equal: A Qualitative Case Study Comparing Traditional and Homebound Instruction Using Technology

    ERIC Educational Resources Information Center

    Fonteix, Kimberly Ann

    2013-01-01

    This qualitative multi-case study explored the perceptions and beliefs of teachers of students in Grade 9 and 10, at a high school in south-central New Jersey, who taught traditional classroom courses that incorporated technology, regarding their lived experiences delivering homebound instruction for the same curriculum. Technology used in the…

  9. Studies in matter antimatter separation and in the origin of lunar magnetism

    NASA Technical Reports Server (NTRS)

    Barker, W. A.; Greeley, R.; Parkin, C.; Aggarwal, H.; Schultz, P.

    1975-01-01

    A progress report, covering lunar and planetary research is introduced. Data cover lunar ionospheric models, lunar and planetary geology, and lunar magnetism. Wind tunnel simulations of Mars aeolian problems and a comparative study of basaltic analogs of Lunar and Martial volcanic features was discussed.

  10. Preliminary Hydrogeologic Characterization Results from the Wallula Basalt Pilot Study

    SciTech Connect

    B.P. McGrail; E. C. Sullivan; F. A. Spane; D. H. Bacon; G. Hund; P. D. Thorne; C. J. Thompson; S. P. Reidel; F. S. Colwell

    2009-12-01

    The DOE's Big Sky Regional Carbon Sequestration Partnership has completed drilling the first continental flood basalt sequestration pilot borehole to a total depth (TD) of 4,110 feet on the Boise White Paper Mill property at Wallula, Washington. Site suitability was assessed prior to drilling by the 2007-2008 acquisition, processing and analysis of a four-mile, five-line three component seismic swath, which was processed as a single data-dense line. Analysis of the seismic survey data indicated a composite basalt formation thickness of {approx}8,000 feet and absence of major geologic structures (i.e., faults) along the line imaged by the seismic swath. Drilling of Wallula pilot borehole was initiated on January 13, 2009 and reached TD on April 6, 2009. Based on characterization results obtained during drilling, three basalt breccia zones were identified between the depth interval of 2,716 and 2,910 feet, as being suitable injection reservoir for a subsequent CO2 injection pilot study. The targeted injection reservoir lies stratigraphically below the massive Umtanum Member of the Grande Ronde Basalt, whose flow-interior section possesses regionally recognized low-permeability characteristics. The identified composite injection zone reservoir provides a unique and attractive opportunity to scientifically study the reservoir behavior of three inter-connected reservoir intervals below primary and secondary caprock confining zones. Drill cuttings, wireline geophysical logs, and 31one-inch diameter rotary sidewall cores provided geologic data for characterization of rock properties. XRF analyses of selected rock samples provided geochemical characterizations of the rocks and stratigraphic control for the basalt flows encountered by the Wallula pilot borehole. Based on the geochemical results, the pilot borehole was terminated in the Wapshilla Ridge 1 flow of the Grande Ronde Basalt Formation. Detailed hydrologic test characterizations of 12 basalt interflow reservoir

  11. Molecular Modeling Study of Chiral Separation and Recognition Mechanism of β-Adrenergic Antagonists by Capillary Electrophoresis

    PubMed Central

    Li, Wuhong; Liu, Changhai; Tan, Guangguo; Zhang, Xinrong; Zhu, Zhenyu; Chai, Yifeng

    2012-01-01

    Chiral separations of five β-adrenergic antagonists (propranolol, esmolol, atenolol, metoprolol, and bisoprolol) were studied by capillary electrophoresis using six cyclodextrins (CDs) as the chiral selectors. Carboxymethylated-β-cyclodextrin (CM-β-CD) exhibited a higher enantioselectivity power compared to the other tested CDs. The influences of the concentration of CM-β-CD, buffer pH, buffer concentration, temperature, and applied voltage were investigated. The good chiral separation of five β-adrenergic antagonists was achieved using 50 mM Tris buffer at pH 4.0 containing 8 mM CM-β-CD with an applied voltage of 24 kV at 20 °C. In order to understand possible chiral recognition mechanisms of these racemates with CM-β-CD, host-guest binding procedures of CM-β-CD and these racemates were studied using the molecular docking software Autodock. The binding free energy was calculated using the Autodock semi-empirical binding free energy function. The results showed that the phenyl or naphthyl ring inserted in the hydrophobic cavity of CM-β-CD and the side chain was found to point out of the cyclodextrin rim. Hydrogen bonding between CM-β-CD and these racemates played an important role in the process of enantionseparation and a model of the hydrogen bonding interaction positions was constructed. The difference in hydrogen bonding formed with the –OH next to the chiral center of the analytes may help to increase chiral discrimination and gave rise to a bigger separation factor. In addition, the longer side chain in the hydrophobic phenyl ring of the enantiomer was not beneficial for enantioseparation and the chiral selectivity factor was found to correspond to the difference in binding free energy. PMID:22312281

  12. Selective separation and characterization of the stress degradation products of ondansetron hydrochloride by liquid chromatography with quadrupole time-of-flight mass spectrometry.

    PubMed

    Talluri, Murali V N Kumar; Keshari, Kundan Kumar; Kalariya, Pradipbhai D; Srinivas, Ragampeta

    2015-05-01

    Ondansetron hydrochloride was subjected to forced degradation studies under various conditions of hydrolysis (acidic, basic, and neutral), oxidation, photolysis, and thermal as prescribed by International Conference on Harmonisation guideline Q1A (R2). A simple, selective, precise, and accurate high-performance liquid chromatography method was developed on a Waters Xterra C18 (150 × 4.6 mm id, 3.5 μm) column using 10 mM ammonium formate (pH 3.0)/methanol as a mobile phase in gradient elution mode at a flow rate of 0.6 mL/min. The method was extended to liquid chromatography quadrupole time-of-flight tandem mass spectrometry for identification and structural characterization of stress degradation products of ondansetron. The drug showed significant degradation in base hydrolytic and photolytic stress conditions in the liquid state, while it was found to be stable in neutral, acidic, thermal, and oxidative stress conditions. A total of five degradation products were characterized and most probable mechanisms for the formation of degradation products have been proposed on the basis of a comparison of the fragmentation of the [M + H](+) ions of the drug and its degradation products. Finally, the developed method was validated in terms of specificity, linearity, accuracy, precision, and robustness as per International Conference on Harmonisation guideline Q2 (R1).

  13. Analysis and Methane Gas Separations Studies for City of Marsing, Idaho An Idaho National Laboratory Technical Assistance Program Study

    SciTech Connect

    Christopher Orme

    2012-08-01

    Introduction and Background Large amounts of methane in well water is a wide spread problem in North America. Methane gas from decaying biomass and oil and gas deposits escape into water wells typically through cracks or faults in otherwise non-porous rock strata producing saturated water systems. This methane saturated water can pose several problems in the delivery of drinking water. The problems range from pumps vapor locking (cavitating), to pump houses exploding. The City of Marsing requested Idaho National Laboratory (INL) to assist with some water analyses as well as to provide some engineering approaches to methane capture through the INL Technical Assistance Program (TAP). There are several engineering approaches to the removal of methane and natural gas from water sources that include gas stripping followed by compression and/or dehydration; membrane gas separators coupled with dehydration processes, membrane water contactors with dehydration processes.

  14. RADIOSYNTHESIS AND CHIRAL SEPARATION OF C-11 LABELED BORONOPHENYLALANINE FOR BNCT STUDIES WITH PET.

    SciTech Connect

    STUDENOV,A.; DING,Y.S.; FERRIERI,R.; MIURA,M.; CODERRE,J.; FOWLER,J.S.

    2001-06-10

    The overall goal of this research is to combine two powerful methodologies, boron neutron capture therapy (BNCT) and positron emission tomography (PET), to advance the treatment of patients with malignant brain tumors. BNCT is a method to selectively deliver lethal alpha radiation to a tumor through the administration of a boron-10 containing drug, and irradiation of the tumor area with neutrons [1]. L-Boronophenylalanine (L-{sup 10}BPA) is a boron-10 containing amino acid currently used for BNCT [4]. In order to perform neutron dosimetry, it is essential to determine tumor boron-10 levels in the course of the therapy. PET has the ability to measure the concentration of drugs labeled with positron-emitting isotopes in the human body [2]. 2-Fluoro-4-borono-phenylalanine ([{sup 18}F]FBPA) has been labeled as a surrogate marker for L-BPA for pharmacokinetic studies in brain tumor patients [3]. However, [{sup 18}F]FBPA is a different drug than L-BPA because it contains a fluorine atom. We report here the labeling of L-BPA with C-11, which has the advantage of being chemically identical to L-BPA. Carbon-11 is also well suited to repeated studies within the same PET scanning session.

  15. The use of Alpert-Stein Factor Separation Methodology for climate variable interaction studies in hydrological land surface models and crop yield models. In:Factor Separation in the Atmosphere:Application and future prospects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Factor Separation Method (FacSep) is a modeling application that has been utilized in the study of biophysical responses to changes in the environment to assess the relative contribution of different atmospheric factors on a biological system. In this chapter we will discuss crop simulation and...

  16. Improved separation of the curcuminoids, syntheses of their rare earth complexes, and studies of potential antiosteoporotic activity.

    PubMed

    Mawani, Yasmin; Orvig, Chris

    2014-03-01

    The first reported homogenous rare earth curcumin (HCurc; ((1E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,6-diene-3,5-dione)) complexes with the formula ML3, where M(3+) is Eu(III), Gd(III) or Lu(III), were synthesized and characterized by mass spectrometry, infrared spectroscopy and, in the case of the lutetium complex, (1)H NMR spectroscopy. Most importantly an improved separation of the three curcuminoids, HCurc, HDMC ((1E,6E)-1-(4-hydroxy-3-methoxyphenyl)-7-(4-hydroxyphenyl)hepta-1,6-diene-3,5-dione) and HBDMC ((1E,6E)-1,7-bis(4-hydroxyphenyl)hepta-1,6-diene-3,5-dione) was realized using a combination of normal-phase column and phosphate-impregnated preparative-thin layer chromatographies. The toxicities of the metal curcumin complexes and ligands were investigated in MG-63 cells, an osteoblast-like cell line, for potential activity as antiosteoporotic agents.

  17. Greek "red mud" residue: a study of microwave reductive roasting followed by magnetic separation for a metallic iron recovery process.

    PubMed

    Samouhos, Michail; Taxiarchou, Maria; Tsakiridis, Petros E; Potiriadis, Konstantinos

    2013-06-15

    The present research work is focused on the development of an alternative microwave reductive roasting process of red mud using lignite (30.15 wt.%Cfix), followed by wet magnetic separation, in order to produce a raw material suitable for sponge or cast iron production. The reduction degree of iron was controlled by both the reductive agent content and the microwave heating time. The reduction followed the Fe₂O₃ → Fe₃O₄ → FeO → Fe sequence. The dielectric constants [real (ε') and imaginary (ε″) permittivities] of red mud-lignite mixture were determined at 2.45 GHz, in the temperature range of 25-1100 °C. The effect of parameters such as temperature, intensity of reducing conditions, intensity of magnetic field and dispersing agent addition rate on the result of both processes was investigated. The phase's transformations in reduction process with microwave heating were determined by X-ray diffraction analysis (XRD) in combination with thermogravimetric/differential thermal analysis (TGA/DTA). The microstructural and morphological characterization of the produced calcines was carried out by scanning electron microscopy (SEM). At the optimum conditions a magnetic concentrate with total iron concentration of 35.15 and 69.3 wt.% metallization degree was obtained.

  18. Comparative studies of grain size separates of 60009. [lunar soil samples

    NASA Technical Reports Server (NTRS)

    Mckay, D. S.; Morris, R. V.; Dungan, M. A.; Fruland, R. M.; Fuhrman, R.

    1976-01-01

    Five samples from 60009, the lower half of a double drive tube, were analyzed via grain-size methods, with particle types classified and counted in the coarser grain sizes. Studies were undertaken of particle types and distributions by petrographic methods, of magnetic fractions, of the size splits and magnetic splits as analyzed by ferromagnetic resonance (FMR) techniques, of maturity (based on agglutinate content, FMR index Is/FeO, mean size of sub-cm material, magnetic fraction), of possible reworking or mixing in situ, and of depositional history. Maturity indices are in substantial agreement for all of the five samples. Strong positive correlation of percent agglutinates and percent bedrock-derived lithic fragments, combined with negative correlation of those components with percent single crystal plagioclase, argue against in situ reworking of the same soil.

  19. An assessment of separable fluid connector system parameters to perform a connector system design optimization study

    NASA Technical Reports Server (NTRS)

    Prasthofer, W. P.

    1974-01-01

    The key to optimization of design where there are a large number of variables, all of which may not be known precisely, lies in the mathematical tool of dynamic programming developed by Bellman. This methodology can lead to optimized solutions to the design of critical systems in a minimum amount of time, even when there are a great number of acceptable configurations to be considered. To demonstrate the usefulness of dynamic programming, an analytical method is developed for evaluating the relationship among existing numerous connector designs to find the optimum configuration. The data utilized in the study were generated from 900 flanges designed for six subsystems of the S-1B stage of the Saturn 1B space carrier vehicle.

  20. Enantiomeric separation and simulation studies of pheniramine, oxybutynin, cetirizine, and brinzolamide chiral drugs on amylose-based columns.

    PubMed

    Ali, Imran; Al-Othman, Zeid A; Al-Warthan, Abdulrahman; Alam, Syed Dilshad; Farooqi, Javed A

    2014-03-01

    Solid phase extraction (SPE)-chiral separation of the important drugs pheniramine, oxybutynin, cetirizine, and brinzolamide was achieved on the C18 cartridge and AmyCoat (150 x 46 mm) and Chiralpak AD (25 cm x 0.46 cm id) chiral columns in human plasma. Pheniramine, oxybutynin, cetirizine, and brinzolamide were resolved using n-hexane-2-PrOH-DEA (85:15:0.1, v/v), n-hexane-2-PrOH-DEA (80:20:0.1, v/v), n-hexane-2-PrOH-DEA (70:30:0.2, v/v), and n-hexane-2-propanol (90:10, v/v) as mobile phases. The separation was carried out at 25 ± 1 ºC temperature with detection at 225 nm for cetirizine and oxybutynin and 220 nm for pheniramine and brinzolamide. The flow rates of the mobile phases were 0.5 mL min(-1). The retention factors of pheniramine, oxybutynin, cetirizine and brinzolamide were 3.25 and 4.34, 4.76 and 5.64, 6.10 and 6.60, and 1.64 and 2.01, respectively. The separation factors of these drugs were 1.33, 1.18, 1.09 and 1.20 while their resolutions factors were 1.09, 1.45, 1.63 and 1.25, and 1.15, respectively. The absolute configurations of the eluted enantiomers of the reported drugs were determined by simulation studies. It was observed that the order of enantiomers elution of the reported drugs was S-pheniramine > R-pheniramine; R-oxybutynin > S-oxybutynin; S-cetirizine > R-cetirizine; and S-brinzolamide > R-brinzolamide. The mechanism of separation was also determined at the supramolecular level by considering interactions and modeling results. The reported SPE-chiral high-performance liquid chromatography (HPLC) methods are suitable for the enantiomeric analyses of these drugs in any biological sample. In addition, simulation studies may be used to determine the absolute configuration of the first and second eluted enantiomers.

  1. Studies of nuclei separated by zonal centrifugation from liver of rats treated with thioacetamide

    PubMed Central

    Gonzalez-Mujica, F.; Mathias, A. P.

    1973-01-01

    1. The effects of the inclusion of thioacetamide in the diet on the properties of rat liver nuclei were studied both in adolescent rats, in which the parenchymal cells contain diploid nuclei, and in young adult rats, with a high proportion of tetraploid nuclei. 2. These investigations included a survey of the sedimentation properties of the nuclei, the nuclear volumes, content of DNA, RNA and protein, the incorporation in vivo of [3H]thymidine into DNA and [14C]orotate into RNA, and measurements of the activity of RNA polymerase and ribonuclease. These studies were conducted on nuclei fractionated by zonal centrifugation. 3. In both groups of animals, exposure to thioacetamide produced large numbers of nuclei that were abnormal in their chemical composition and enzymic activity. The changes were complex as regards both the types of nuclei that were affected and in their variation with time. 4. In adolescent rats two waves of synthesis of DNA and RNA were observed, one at 3 days and the other after 2 weeks of treatment. The first decline in the incorporations into both DNA and RNA coincided with a decrease in the pool sizes of some of the precursors. The activity of RNA polymerase was not substantially altered. A marked increase in the content of protein was observed before the first wave of synthesis. The normal progressive increase in tetraploid nuclei was prevented. 5. In young adult rats two waves of DNA synthesis were detected. Each was preceded by a large increase in the amount of protein per nucleus but was not accompanied by increased RNA synthesis. After 4 weeks of treatment, the diploid stromal nuclei appeared mainly unaffected and large numbers of tetraploid nuclei with a greatly increased quantity of protein were observed. PMID:4353443

  2. Study of the U/Am separation with supported calix[6]arene in the aim of urinary actinides analysis.

    PubMed

    Poriel, L; Boulet, B; Cossonnet, C; Bouvier-Capely, C

    2007-01-01

    The aim of this work is to propose an alternative radiochemical procedure for the analysis of U, Pu and Am in urine, which is one of the controls used to monitor workers exposed to risk of internal contamination with actinides. Previous studies have demonstrated the extraction efficiency of these molecules towards uranium and plutonium, the affinity of calix[6]arenes bearing hydroxamic acid groups (LHH3) and carboxylic groups (LCH3) towards americium were studied in this paper by solvent extraction. The results showed that LHH3 and LCH3 have a very good affinity for americium and enhance the possibility of separating Pu from U and Am. Experiments were performed to perfect the separation of U/Am. The immobilisation of these calixarenes on polymer supports was also investigated for routine applications. Supported calixarenes LCH3 and LHH3 presented the same performances as those obtained in a liquid-liquid system and, hence, are a promising system for the analysis of actinides. These molecules and their uses have been protected (patent pending).

  3. Spectroscopic study of the microbial community in chemocline zones of relic meromictic lakes separating from the White Sea

    NASA Astrophysics Data System (ADS)

    Kharcheva, Anastasia V.; Krasnova, Elena D.; Voronov, Dmitry A.; Patsaeva, Svetlana V.

    2015-03-01

    As a result of a recent years study on the Karelia shore of the White Sea more than ten relict lakes in different stages of separation from the sea have been discovered. Five of them are located close to the Nikolai Pertsov White Sea Biological Station of Moscow State University. Such separated lakes are interesting to explore for their firm vertical stratification. Water layers differ not only by temperature, salinity and other physic and chemical characteristics and optical properties, but also by ibhabiting microorganisms and by the quality of dissolved organic matter. To study phototropic organisms in water sampled from different depths we used spectroscopic techniques. Identification of the main bands in the absorption and fluorescence spectra showed that there are two main groups of photosynthetic organisms in the redox zone (chemocline): unicellular algae containing chlorophyll a and green sulfur bacteria with bacteriochlorophylls c, d, e. Spectral data were compared with physical and chemical characteristics of the water layer (temperature, salinity, pH, dissolved oxygen and sunlight illumination at certain depth). It gave an opportunity to compare vertical profiles of oxygen and hydrogen sulphide concentration with the number and distribution of oxygenic and anoxygenic phototrophic microorganisms. Maximum abundance of both algae and green sulfur bacteria were achieved within the redox zone. Typical thickness of the layer with the highest concentration of microorganisms did not exceed 10-20 cm.

  4. Tissue type characterization using photoacoustic power spectrum, a feasibility study

    NASA Astrophysics Data System (ADS)

    Tavakoli, Behnoosh; Goldstein, Seth D.; Kang, Jin U.; Choti, Michaal; Boctor, Emad M.

    2015-03-01

    The development of technologies capable of non-invasive characterization of tissue has the potential to significantly improve diagnostic and therapeutic medical interventions. In this study we investigated the feasibility of a noninvasive photoacoustic (PA) approach for characterizing biological tissues. The measurement was performed in the transmission mode with a wideband hydrophone while a tunable Q-switched Nd:YAG pulsed laser was used for illumination. The power spectrum of photoacoustic signal induced by a pulsed laser light from tissue was analyzed and features were extracted to study their correlation with tissue biomechanical properties. For a controlled study, tissue mimicking gelatin phantoms with different densities and equivalent optical absorptions were used as targets. The correlation between gelatin concentration of such phantoms and their mechanical properties were validated independently with a dynamic mechanical analyzer capable of calculating complex loss and storage moduli between two compression plates. It was shown that PA spectrums were shifted towards higher frequencies by increasing gelatin concentration. In order to quantify this effect, signal energy in two intervals of low and high frequency ranges were calculated. Gelatin concentration was correlated with PA energy in high frequency range with R2=0.94. Subsequently, PA signals generated from freshly resected human thyroid specimens were measured and analyzed in a similar fashion. We found that in aggregate, malignant thyroid tissue contains approximately 1.6 times lower energy in the high frequency range in comparison to normal thyroid tissue (p<0.01). This ratio increased with increasing illumination wavelength from 700 nm to 900nm. In summary, this study demonstrated the feasibility of using photoacoustic technique for characterizing tissue on the basis of viscoelastic properties of the tissue.

  5. Gas separating

    DOEpatents

    Gollan, Arye Z.

    1990-12-25

    Feed gas is directed tangentially along the non-skin surface of gas separation membrane modules comprising a cylindrical bundle of parallel contiguous hollow fibers supported to allow feed gas to flow from an inlet at one end of a cylindrical housing through the bores of the bundled fibers to an outlet at the other end while a component of the feed gas permeates through the fibers, each having the skin side on the outside, through a permeate outlet in the cylindrical casing.

  6. Gas separating

    DOEpatents

    Gollan, Arye

    1988-01-01

    Feed gas is directed tangentially along the non-skin surface of gas separation membrane modules comprising a cylindrical bundle of parallel contiguous hollow fibers supported to allow feed gas to flow from an inlet at one end of a cylindrical housing through the bores of the bundled fibers to an outlet at the other end while a component of the feed gas permeates through the fibers, each having the skin side on the outside, through a permeate outlet in the cylindrical casing.

  7. Dust separator

    SciTech Connect

    Borow, H.

    1987-01-27

    This patent describes a gas filter apparatus for separating solids from a gas stream comprising a housing having a top, base, and side walls defining a chamber, a partition wall extending across the chamber and separating the chamber into an upper compartment and a lower compartment. A gas inlet conveyor tube in the chamber passes downwardly of the partition and into the lower compartment, the portion of the conveyor tube passing through the upper compartment being impervious and the portion of the conveyor tube extending downwardly into the lower compartment being provided with exit means including exit apertures at least in the area of the conveyor tube adjacent the partition wall. The partition wall is provided with openings surrounding the conveyor tube and communicates the lower compartment with the upper compartment. A filter means in the form of filter tubes covers each opening in the partition wall and extends downwardly in the lower compartment and parallel to the conveyor tube, at least one gas outlet communicating with the upper compartment. A suction means is associated with the gas outlet to provide a reduced pressure within the chamber. A discharge means at the base of the housing is associated with the lower compartment for discharging solid matter separated from the gas stream. The solid laden gas is conveyed into the lower compartment downwardly by the conveying tube and the gas of the stream is drawn from the conveyor tube immediately past the partition, through the surrounding filter tubes in order to prevent the formation of counter gas flows to the gravity discharge of the solids being separated from the gas stream.

  8. Monte Carlo Studies of Phase Separation in Compressible 2-dim Ising Models

    NASA Astrophysics Data System (ADS)

    Mitchell, S. J.; Landau, D. P.

    2006-03-01

    Using high resolution Monte Carlo simulations, we study time-dependent domain growth in compressible 2-dim ferromagnetic (s=1/2) Ising models with continuous spin positions and spin-exchange moves [1]. Spins interact with slightly modified Lennard-Jones potentials, and we consider a model with no lattice mismatch and one with 4% mismatch. For comparison, we repeat calculations for the rigid Ising model [2]. For all models, large systems (512^2) and long times (10^ 6 MCS) are examined over multiple runs, and the growth exponent is measured in the asymptotic scaling regime. For the rigid model and the compressible model with no lattice mismatch, the growth exponent is consistent with the theoretically expected value of 1/3 [1] for Model B type growth. However, we find that non-zero lattice mismatch has a significant and unexpected effect on the growth behavior.Supported by the NSF.[1] D.P. Landau and K. Binder, A Guide to Monte Carlo Simulations in Statistical Physics, second ed. (Cambridge University Press, New York, 2005).[2] J. Amar, F. Sullivan, and R.D. Mountain, Phys. Rev. B 37, 196 (1988).

  9. Studies on separation and pharmacokinetics of m-nisoldipine enantiomers in beagle dog plasma by LC/MS/MS.

    PubMed

    Li, Min; Yuan, Lin; Li, Xiuqing; Zhi, Xuran; Sheng, Ning; Zhang, Lantong

    2013-11-01

    A rapid, sensitive and selective liquid chromatography-tandem mass spectrometric (LC/MS/MS) method was developed and validated for the separation and determination of m-nisoldipine enantiomers in beagle dog plasma. Samples were pretreated by a single-step protein precipitation with acetonitrile. After m-nisoldipine racemic administration to beagle dogs, samples of m-nisoldipine enantiomers in beagle dog plasma were separated and determined on a ULTRON ES-OVM column (150 × 4.6 mm, 5 μm) at 20°C with a mobile phase consisted of methanol-acetonitrile-ammonium acetate (pH 7.0; 2mM) (15:15:70, v/v/v) at a flow rate of 0.8 mL/min. Chromatograms were monitored at 237 nm, and the API 4000 triple quadrupole mass spectrometer was operated in multiple reaction monitoring (MRM) scan mode using ElectroSpray ionization (ESI) source. The good linearity (rs=0.9958 and rr=0.9983) were found in the range 0.25-20 ng/mL. The lower limit of quantification (LLOQ) obtained was 0.25 ng/mL (n=6). All the validation data, such as accuracy, precision, intra-day and inter-day repeatability, were within the required limits. The method was successfully applied to separation and pharmacokinetics of m-nisoldipine enantiomers in beagle dog plasma. The result of statistics analysis shows that there are no significant differences between R-(-)-m-nisoldipine and S-(+)-m-nisoldipine (p>0.05). The study provides necessary evidences for the research and new drug development of m-nisoldipine enantiomers.

  10. A detached eddy simulation model for the study of lateral separation zones along a large canyon-bound river

    NASA Astrophysics Data System (ADS)

    Alvarez, Laura V.; Schmeeckle, Mark W.; Grams, Paul E.

    2017-01-01

    Lateral flow separation occurs in rivers where banks exhibit strong curvature. In canyon-bound rivers, lateral recirculation zones are the principal storage of fine-sediment deposits. A parallelized, three-dimensional, turbulence-resolving model was developed to study the flow structures along lateral separation zones located in two pools along the Colorado River in Marble Canyon. The model employs the detached eddy simulation (DES) technique, which resolves turbulence structures larger than the grid spacing in the interior of the flow. The DES-3D model is validated using Acoustic Doppler Current Profiler flow measurements taken during the 2008 controlled flood release from Glen Canyon Dam. A point-to-point validation using a number of skill metrics, often employed in hydrological research, is proposed here for fluvial modeling. The validation results show predictive capabilities of the DES model. The model reproduces the pattern and magnitude of the velocity in the lateral recirculation zone, including the size and position of the primary and secondary eddy cells, and return current. The lateral recirculation zone is open, having continuous import of fluid upstream of the point of reattachment and export by the recirculation return current downstream of the point of separation. Differences in magnitude and direction of near-bed and near-surface velocity vectors are found, resulting in an inward vertical spiral. Interaction between the recirculation return current and the main flow is dynamic, with large temporal changes in flow direction and magnitude. Turbulence structures with a predominately vertical axis of vorticity are observed in the shear layer becoming three-dimensional without preferred orientation downstream.

  11. Separation system

    DOEpatents

    Rubin, Leslie S.

    1986-01-01

    A separation system for dewatering radioactive waste materials includes a disposal container, drive structure for receiving the container, and means for releasably attaching the container to the drive structure. Separation structure disposed in the container adjacent the inner surface of the side wall structure retains solids while allowing passage of liquids. Inlet port structure in the container top wall is normally closed by first valve structure that is centrifugally actuated to open the inlet port and discharge port structure at the container periphery receives liquid that passes through the separation structure and is normally closed by second valve structure that is centrifugally actuated to open the discharge ports. The container also includes coupling structure for releasable engagement with the centrifugal drive structure. Centrifugal force produced when the container is driven in rotation by the drive structure opens the valve structures, and radioactive waste material introduced into the container through the open inlet port is dewatered, and the waste is compacted. The ports are automatically closed by the valves when the container drum is not subjected to centrifugal force such that containment effectiveness is enhanced and exposure of personnel to radioactive materials is minimized.

  12. Physical characterization and in vitro biological impact of highly aggregated antibodies separated into size-enriched populations by fluorescence-activated cell sorting

    PubMed Central

    Telikepalli, Srivalli; Shinogle, Heather E.; Thapa, Prem S.; Kim, Jae Hyun; Deshpande, Meghana; Jawa, Vibha; Middaugh, C. Russell; Narhi, Linda O.; Joubert, Marisa K.; Volkin, David B.

    2015-01-01

    An IgG2 monoclonal antibody (mAb) solution was subjected to stirring, generating high concentrations of nanometer and subvisible particles, which were then successfully size enriched into different size bins by low speed centrifugation or a combination of gravitational sedimentation and Fluorescence-Activated Cell Sorting (FACS). The size-fractionated mAb particles were assessed for their ability to elicit the release of cytokines from a population of donor-derived human peripheral blood mononuclear cells (PBMC) at two phases of the immune response. Fractions enriched in nanometer-sized particles showed a lower response than those enriched in micron-sized particles in this assay. Particles of 5–10 μm in size displayed elevated cytokine release profiles compared to other size ranges. Stir-stressed mAb particles had amorphous morphology, contained protein with partially altered secondary structure, elevated surface hydrophobicity (compared to controls), and trace levels of elemental fluorine. FACS size-enriched the mAb particle samples, yet did not notably alter the overall morphology or composition of particles as measured by Microflow imaging, Transmission Electron Microscopy, and Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy. The utility and limitations of FACS for size separation of mAb particles and potential of in-vitro PBMC studies to rank order the immunogenic potential of various types of mAb particles is discussed. PMID:25753756

  13. Application of capillary isotachophoresis-based multidimensional separations coupled with electrospray ionization-tandem mass spectrometry for characterization of mouse brain mitochondrial proteome

    PubMed Central

    Fang, Xueping; Wang, Weijie; Yang, Li; Chandrasekaran, Krish; Kristian, Tibor; Balgley, Brian M.; Lee, Cheng S.

    2017-01-01

    By employing a capillary ITP (CITP)/CZE-based proteomic technology, a total of 1795 distinct mouse Swiss-Prot protein entries (or 1705 nonredundant proteins) are identified from synaptic mitochondria isolated from mouse brain. The ultrahigh resolving power of CITP/CZE is evidenced by the large number of distinct peptide identifications measured from each CITP fraction together with the low peptide fraction overlapping among identified peptides. The degree of peptide overlapping among CITP fractions is even lower than that achieved using combined CIEF/nano-RP LC separations for the analysis of the same mitochondrial sample. When evaluating the protein sequence coverage by the number of distinct peptides mapping to each mitochondrial protein identification, CITP/CZE similarly achieves superior performance with 1041 proteins (58%) having 3 or more distinct peptides, 233 (13%) having 2 distinct peptides, and 521 (29%) having a single distinct peptide. The reproducibility of protein identifications is found to be around 86% by comparing proteins identified from repeated runs of the same mitochondrial sample. The analysis of the mouse mitochondrial proteome by two CITP/CZE runs results in the detection of 2095 distinct mouse Swiss-Prot protein entries (or 1992 nonredundant proteins), corresponding to 59% coverage of the updated Maestro mitochondrial reference set. The collective analysis from combined CITP/CZE and CIEF-based proteomic studies yields the identification of 2191 distinct mitochondrial protein entries (or 2082 nonredundant proteins), corresponding to 76% coverage of the MitoP2-database reference set. PMID:18425750

  14. Site characterization and impact study prototype for secondary schools

    SciTech Connect

    Davin, R.G.

    1995-12-01

    Secondary Education tends to be departmentalized to a degree that science disciplines are taught as separate entities with concepts and programs that are fragmented from the aggregate base of scientific knowledge. There is a need to synthesize these disciplines into one curricula that will provide a holistic approach rather than a narrow focus. Isolated disciplines foster isolated and disjointed strategies in environmental problem solving. Real world solutions to environmental challenges require an interdisciplinary team of specialists if goals are to be realized. This prototype incorporates various aspects of an impact study, including air and water quality, wildlife resources, agriculture and forest land, geologic data, socioeconomic impacts, historic and cultural preservation, politics and aesthetics into one curriculum to demonstrate the interconnectedness of these subjects.

  15. Characterization of adhesive from oysters: A structural and compositional study

    NASA Astrophysics Data System (ADS)

    Alberts, Erik

    The inability for man-made adhesives to set in wet or humid environments is an ongoing challenging the design of biomedical and marine adhesive materials. However, we see that nature has already overcome this challenge. Mussels, barnacles, oysters and sandcastle worms all have unique mechanisms by which they attach themselves to surfaces. By understanding what evolution has already spent millions of years perfecting, we can design novel adhesive materials inspired by nature's elegant designs. The well-studied mussel is currently the standard for design of marine inspired biomimetic polymers. In the work presented here, we aim to provide new insights into the adhesive produced by the eastern oyster, Crassostrea virginica. Unlike the mussel, which produces thread-like plaques comprised of DOPA containing-protein, the oyster secretes an organic-inorganic hybrid adhesive as it settles and grows onto a surface. This form of adhesion renders the oyster to be permanently fixed in place. Over time, hundreds of thousands of oyster grow and agglomerate to form extensive reef structures. These reefs are not only essential to survival of the oyster, but are also vital to intertidal ecosystems. While the shell of the oyster has been extensively studied, curiously, only a few conflicting insights have been made into the nature of the adhesive and contact zone between shell and substrate, and even lesfs information has been ascertained on organic and inorganic composition. In this work, we provide microscopy and histochemical studies to characterize the structure and composition of the adhesive, using oyster in the adult and juvenile stages of life. Preliminary work on extracting and characterizing organic components through collaborative help with solid-state NMR (SSNMR) and proteomics are also detailed here. We aim to provide a full, comprehensive characterization of oyster adhesive so that in the future, we may apply what we learn to the design of new materials.

  16. Site characterization studies in high plateau of Tibet

    NASA Astrophysics Data System (ADS)

    Yao, Yongqiang; Wang, Hongshuai; Liu, Liyong; Wang, Yiping; Qian, Xuan; Yin, Jia

    2012-09-01

    The site survey in western China has been carried out since 2003. Remote studies and local surveys are performed, and Oma site, Ali area in southwest Tibet, has been selected in 2005 to make site testing measurements. The monitoring results show that Ali area can be the best choice for astronomical observations over the East Asian regions. A new site in Ali has been identified and begun construction in 2010 for small telescopes and detailed site characterization. This paper reviews the long term site survey, presents site characteristics in Tibet, and introduces current status of the new Ali observatory.

  17. Synthesis and characterization of organotin containing copolymers: reactivity ratio studies.

    PubMed

    Al-Deyab, Salem S; Al-Hazmi, Ali Mohsen; El-Newehy, Mohamed H

    2010-03-12

    Organotin monomers containing dibutyltin groups--dibutyltin citraconate (DBTC) as a new monomer and dibutyltin maleate (DBTM)--were synthesized. Free radical copolymerizations of the organotin monomers with styrene (ST) and butyl acrylate (BA) were performed. The overall conversion was kept low (< or = 15% wt/wt) for all studied samples and the copolymers composition was determined from tin analysis using the Gillman and Rosenberg method. The reactivity ratios were calculated from the copolymer composition using the Fineman-Ross (FR) method. The synthesized monomers were characterized by elemental analysis, 1H-, 13C-NMR and FTIR spectroscopy.

  18. Electrostatic separation for recycling waste printed circuit board: a study on external factor and a robust design for optimization.

    PubMed

    Hou, Shibing; Wu, Jiang; Qin, Yufei; Xu, Zhenming

    2010-07-01

    Electrostatic separation is an effective and environmentally friendly method for recycling waste printed circuit board (PCB) by several kinds of electrostatic separators. However, some notable problems have been detected in its applications and cannot be efficiently resolved by optimizing the separation process. Instead of the separator itself, these problems are mainly caused by some external factors such as the nonconductive powder (NP) and the superficial moisture of feeding granule mixture. These problems finally lead to an inefficient separation. In the present research, the impacts of these external factors were investigated and a robust design was built to optimize the process and to weaken the adverse impact. A most robust parameter setting (25 kv, 80 rpm) was concluded from the experimental design. In addition, some theoretical methods, including cyclone separation, were presented to eliminate these problems substantially. This will contribute to efficient electrostatic separation of waste PCB and make remarkable progress for industrial applications.

  19. Characterization and Thermodynamics Studies of Feldspar and Feldspathoid Minerals

    NASA Astrophysics Data System (ADS)

    Rudow, M.; Lilova, K.

    2015-12-01

    The application of thermal analysis and calorimetry for the studies of minerals has a history as long as the existence of the thermal methods themselves. New advanced calorimetric techniques have been developed for more accurate characterization of both bulk and nano materials thus impacting their design, processing, and applications. TG-DTA and TG-DSC are used to characterize the composition of complex minerals (e.g. [KxNa1-x(AlSi3)O8]) based on the weight changes and phase transformations observed with temperature increase. Additionally, those techniques allow to determine the quantity of the different types of water contained in natural feldspars and feldspathoids (absorbed, interlayer, structural). The results for several clays will be discussed. The geochemical properties and thermal stability of another class of minerals - aluminosilicate frameworks (alkali sodalities, natrolites, etc.) as related to high-level nuclear waste treatment facilities, radioactive waste storage and management were studied. The natural sodalite Na8[Al6Si6O24]Cl2 and similar frameworks with different anions are part of sodium-aluminosilicate (NAS) low activity radioactive waste produced during steam reforming process treatment. The enthalpies and entropies of formation and the hydration enthalpies of the above-mentioned feltspathoids are obtained and the effect of the different cations and anions on the thermodynamic stability was studied. The results will allow to predict the long term behavior of the compounds in the environment under different conditions.

  20. Simulation of π0separation study for proposed CMS forward electromagnetic calorimeter

    SciTech Connect

    Roy, Ashim; Jain, Shilpi; Banerjee, Sunanda; Bhattacharya, Satyaki; Majumder, Gobinda

    2016-11-11

    The Forward Electromagnetic Calorimeter of the CMS detector is going to be upgraded in the high luminosity running as the energy of the present Electromagnetic Calorimeter (PbWO4) will degrade in the high luminosity (luminosity 1034 cm-2 s-1) running due to extensive radiation (hadron flux 1013 neutrons cm,-2). Shashlik Electromagnetic Calorimeter which consists of alternate layers of 1.5 mm LYSO(Ce) crystal plates and 2.5 mm Tungsten absorbers, was a proposal for high luminosity running. One of the performance points for any electromagnetic calorimeter is the ability to separate π0 s from true photons, since final states with photons are a clean and one of the most important final states in proton-proton collisions at the LHC. As a result, the objective of this project is to study the possibility of π0 and γ separation in the Shashlik detector using Multivariate Analysis (MVA) technique.