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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. Separation, Characterization and Initial Reaction Studies of Magnetite Particles from Hanford Sediments

    SciTech Connect

    Baer, Donald R.; Grosz, Andrew E.; Ilton, Eugene S.; Krupka, Kenneth M.; Liu, Juan; Penn, Ryland L.; Pepin, Alex

    2010-04-24

    Magnetic and density separation methods have been applied to composite sediment sample from the Hanford formation from sediment recovered during drilling of an uncontaminated borehole located near the 200 West Area of the Hanford Site in southeastern Washington State. This paper describes the results of using those separation methods and from the characterization and initial reactivity measurements on a highly magnetic fraction isolated from that sediment. X-ray diffraction (XRD) analysis of the highly magnetic sediment fraction indicates that this material contains predominantly magnetite (Fe3O4). Particle morphology observed by scanning electron microscopy (SEM) and compositions determined energy dispersive spectroscopy (EDS) are consistent with this identification. Analyses by X-ray photoelectron spectroscopy (XPS) indicates that there is a thin coating on the particles that are likely a type of aluminosilicate. This highly magnetic fraction of material is not reactive with indigo carmine, an organic redox probe molecule that was shown to readily react with synthetic magnetite. Because of the limited amounts of material readily available, initial tests have been conducted that demonstrate the ability to complete U(VI) sorption on individual particles (nominally ~100 µm in size) of the isolated sediment and to remove and mount these individual particles for analysis of the concentration and chemical state of the sorbed U species using small area XPS.

  3. Characterization of gelatin-agar based phase separated hydrogel, emulgel and bigel: a comparative study.

    PubMed

    Wakhet, Senggam; Singh, Vinay K; Sahoo, Saikat; Sagiri, Sai Sateesh; Kulanthaivel, Senthilguru; Bhattacharya, Mrinal K; Kumar, Naresh; Banerjee, Indranil; Pal, Kunal

    2015-02-01

    The current study describes the in-depth characterization of agar-gelatin based co-hydrogels, emulgels and bigels to have an insight about the differences in the properties of the formulations. Hydrogels have been extensively studied as vehicle for controlled drug release, whereas, the concept of emulgels and bigels is relatively new. The formulations were characterized by scanning electron microscopy, FTIR spectroscopy, XRD and mechanical properties. The biocompatibility and the ability of the formulations to be used as drug delivery vehicle were also studied. The scanning electron micrographs suggested the presence of internal phases within the agar-gelatin composite matrices of co-hydrogel, emulgel and bigel. FTIR and XRD studies suggested higher crystallinity of emulgels and bigels. Electrical impedance and mechanical stability of the emulgel and the bigel was higher than the hydrogel. The prepared formulations were found to be biocompatible and suitable for drug delivery applications.

  4. 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.

  5. 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.

  6. Characterization and separation of charged particles

    SciTech Connect

    Mukherjee, A.

    1987-01-01

    An investigation into the removal of electrically charged particles by using an electric field was carried out in both liquid and gaseous media. The systems studied in liquid media were clay particles suspended in synthetic fuels such as tar sand extracts and shale oils, whereas in gaseous media, the electrostatic removal of pyrites from coal was the objective. For proper design of separation equipment the charge of the particles was characterized as a function of the system variables. For the systems studied in the liquid media, the charge of the particles arises due to the adsorption of asphaltenes present in the synthetic fuel. The magnitude of the charge is strongly dependent on the amount of adsorbed asphaltenes. Small quantities of water have a drastic effect on the charge of the particles. As a result of the particle charge, a crossflow electrofilter can be used to completely remove these particles from the synthetic fuels. In gaseous media, the particles get charged by triboelectrification. The charge of pyrites and coal was measured in a continuous recirculating pneumatic conveyor using a ball probe as well as a Faraday cage. The charge of both coal and pyrites depends on the solid velocity, humidity, particle size, solids concentration, and surface oxidation. In most cases there is a sufficient charge difference between coal and pyrites to provide a driving force for electrostatic separation. Based on the charge difference a novel electrostatic separator was constructed. An improvement in the separator was made using a hydrodynamic model for two phase flow. Good agreement between the predictions of the model and experimental results were obtained.

  7. 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.

  8. 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.

  9. Synthesis, characterization and separation of chiral and achiral diastereomers of Schiff base Pd(II) complex: A comparative study of their DNA- and HSA-binding.

    PubMed

    Kazemi, Zahra; Amiri Rudbari, Hadi; Sahihi, Mehdi; Mirkhani, Valiollah; Moghadam, Majid; Tangestaninejad, Sharam; Mohammadpoor-Baltork, Iraj; Azimi, Gholamhassan; Gharaghani, Sajjad; Kajani, Abolghasem Abbasi

    2016-10-01

    A racemic mixture of a new chiral Schiff base ligand (HL: R/S-(1-phenylethylimino)methylnaphtalen-2-ol) has been utilized to prepare Pd(II) complex. Crystallization technique has been employed to separate diastereomeric pairs of Pd(II) complex: (mesoPdL2) and (racPdL2) that in this paper are known as PdL2(1) and PdL2(2), respectively. The synthesized complexes have been characterized by means of elemental analysis (CHN), FT-IR, (1)H and (13)C NMR spectroscopies. Moreover, PdL2(1) has been structurally characterized by single-crystal X-ray diffraction. The geometry around the metal center is square-planar. The interaction of two diastereomers of Pd(II) complex with FS-DNA has been explored, using UV-vis spectroscopy, fluorescence quenching, chemometrics and viscosity measurement methods. The PdL2(1) exhibited higher binding constant, about 10-fold, (1.0×10(6)M(-1)) as compared to PdL2(2) (1.51.5×10(5)M(-1)). Moreover, the human serum albumin (HSA) binding ability has been monitored by absorption, quenching of tryptophan fluorescence emission and circular dichroism (CD) studies. The slight difference is observed between HSA binding affinity with the complexes: PdL2(1) (6.2×10(4)M(-1)) and PdL2(2) (3.3×10(4)M(-1)). Also, the thermodynamic parameters were determined at three different temperatures (298, 308 and 318K). In this study, molecular docking was also carried out to confirm and illustrate the specific DNA- and HSA-binding of the Pd(II) complexes. In the PdL2(1)-HSA system a T-shaped π-π interaction with PHE206 was observed. While in the PdL2(2)-HSA system there are a hydrogen bond, a π-cation and two T-shaped π-π interactions with ASB324, LYS212 and PHE228, respectively. The groove binding mode of DNA interaction has been proposed for both diastereomers.

  10. Synthesis, characterization and separation of chiral and achiral diastereomers of Schiff base Pd(II) complex: A comparative study of their DNA- and HSA-binding.

    PubMed

    Kazemi, Zahra; Amiri Rudbari, Hadi; Sahihi, Mehdi; Mirkhani, Valiollah; Moghadam, Majid; Tangestaninejad, Sharam; Mohammadpoor-Baltork, Iraj; Azimi, Gholamhassan; Gharaghani, Sajjad; Kajani, Abolghasem Abbasi

    2016-10-01

    A racemic mixture of a new chiral Schiff base ligand (HL: R/S-(1-phenylethylimino)methylnaphtalen-2-ol) has been utilized to prepare Pd(II) complex. Crystallization technique has been employed to separate diastereomeric pairs of Pd(II) complex: (mesoPdL2) and (racPdL2) that in this paper are known as PdL2(1) and PdL2(2), respectively. The synthesized complexes have been characterized by means of elemental analysis (CHN), FT-IR, (1)H and (13)C NMR spectroscopies. Moreover, PdL2(1) has been structurally characterized by single-crystal X-ray diffraction. The geometry around the metal center is square-planar. The interaction of two diastereomers of Pd(II) complex with FS-DNA has been explored, using UV-vis spectroscopy, fluorescence quenching, chemometrics and viscosity measurement methods. The PdL2(1) exhibited higher binding constant, about 10-fold, (1.0×10(6)M(-1)) as compared to PdL2(2) (1.51.5×10(5)M(-1)). Moreover, the human serum albumin (HSA) binding ability has been monitored by absorption, quenching of tryptophan fluorescence emission and circular dichroism (CD) studies. The slight difference is observed between HSA binding affinity with the complexes: PdL2(1) (6.2×10(4)M(-1)) and PdL2(2) (3.3×10(4)M(-1)). Also, the thermodynamic parameters were determined at three different temperatures (298, 308 and 318K). In this study, molecular docking was also carried out to confirm and illustrate the specific DNA- and HSA-binding of the Pd(II) complexes. In the PdL2(1)-HSA system a T-shaped π-π interaction with PHE206 was observed. While in the PdL2(2)-HSA system there are a hydrogen bond, a π-cation and two T-shaped π-π interactions with ASB324, LYS212 and PHE228, respectively. The groove binding mode of DNA interaction has been proposed for both diastereomers. PMID:27599112

  11. 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.

  12. 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. PMID:26787682

  13. 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.

  14. 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

  15. Characterization of thermally separated poly (alkylene glycol) polymer quenchants by ESR spectroscopy

    SciTech Connect

    McLeod, D. Jr.; Totten, G.E.; Webster, G.M.

    1996-12-31

    Poly(alkylene glycol) - PAG copolymers are the most commonly used polymer quenchants in the world today. One of the distinguishing and advantageous features of these polymers is their ability to undergo thermal separation. This may occur at the hot metal interface during quenching or in solution as a means of recycling contaminated quench baths. In this paper, the use of electron spin resonance (ESR) spectroscopy to characterize PAG polymers that have been thermally separated from aqueous solution will be reported. Exploratory studies using ESR spectroscopy to characterize thermally separated polymer films during quenching will also be reported.

  16. 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

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. Separation and characterization of respirable amphibole fibers from Libby, Montana.

    PubMed

    Webber, James S; Blake, David J; Ward, Tony J; Pfau, Jean C

    2008-06-01

    The vermiculite mine in Libby, Montana, was in operation for over 70 yr and was contaminated with asbestos-like amphibole fibers. The mining, processing, and shipping of this vermiculite led to significant fiber inhalation exposure throughout the community, and residents of Libby have developed numerous pulmonary diseases such as lung cancer and mesothelioma. The present study describes the separation of Libby 6-mix into respirable and nonrespirable size fractions by means of aqueous elutriation. The elutriator, designed to separate fibers with aerodynamic diameters smaller than 2.5 microm (respirable) from larger fibers, used an upward flow rate of 3.4 x 10(- 4) cm s(-1). The resultant respirable fraction constituted only 13% of the raw Libby 6-mix mass, and less than 2% of the fibers in the elutriated fraction had aerodynamic diameters exceeding 2.5 microm. Surface area of the elutriated fibers was 5.3 m(- 2) g(-1), compared to 0.53 m(-2) g(-1) for the raw fibers. There were no detectable differences in chemical composition between the larger and smaller fibers. Such harvesting of respirable fractions will allow toxicological studies to be conducted within a controlled laboratory setting, utilizing fiber sizes that may more accurately simulate historical exposure of Libby residents' lungs. Importantly, this work describes a method that allows the use of material enriched in more uniform respirable material than raw Libby 6-mix, making comparisons with other known fiber preparations more valid on a mass basis.

  2. 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.

  3. 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.

  4. 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,

  5. 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.

  6. 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

  7. 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.

  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. 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.

  10. A Numerical Study of Low-Reynolds-Number Separation Bubbles

    NASA Technical Reports Server (NTRS)

    Tatineni, Mahidhar; Zhong, Xiao-Lin

    1999-01-01

    The present study uses two dimensional numerical simulations to study unsteady low-Reynolds-number separation bubbles. The numerical study is in two parts: (1) a two dimensional time-accurate Navier-Stokes solver is used to simulate flows over the APEX airfoil, and (2) a numerical procedure is developed for localized simulations of transitional separation bubbles. The 2-D computations of flow over the APEX airfoil show that the flow is unsteady with periodic vortex shedding. A linear stability analysis of the separated flow shows that the vortex shedding is caused due to the instability of the separated flow. For transonic flows over the APEX airfoil the vortex shedding is additionally influenced by the presence of shocks. The flowfield has two characteristic time scales, one corresponding to the vortex shedding and another corresponding to the movement of the shocks. The two dimensional (2-D) airfoil simulations also showed the presence of nonlinear effects in the separated region. To better understand the characteristics of separation bubbles a numerical procedure has been developed for localized separation bubble calculations. This procedure is used to perform computations for a flat plate separation bubble test case. The separation bubble is induced by specifying a velocity gradient in the freestream. The growth of disturbances in the separation bubble is analyzed by introducing disturbances upstream of the separation bubble.

  11. Online SERS Detection and Characterization of Eight Biologically-Active Peptides Separated by Capillary Zone Electrophoresis

    PubMed Central

    Negri, Pierre; Sarver, Scott A.; Schiavone, Nicole M.; Dovichi, Norman J.; Schultz, Zachary D.

    2015-01-01

    There is a need for low cost, sensitive and chemical specific detectors for routine characterization of biomolecules. In this study, we utilize sheath-flow surface-enhanced Raman scattering (SERS) to analyze a mixture of eight biologically-active peptides separated by capillary zone electrophoresis (CZE). Analysis of the SERS electropherogram resulting from online detection resolves the characteristic Raman bands attributed to the amino acid constituents of each peptide, which enables identification. The detection limit by SERS was found to be 10−8 M. Our results suggest that the structural information obtained from the detected vibrational modes provides complementary characterization to other chemically specific detectors like mass spectrometry and improved chemical identification over other commonly used optical-based post-chromatographic detection methods. In addition, the sheath-flow SERS detection results in band narrowing in the observed electropherogram that enables distinction of closely migrating species. The results presented here indicate that online SERS detection can provide fast, robust, reproducible, and chemical specific detection to facilitate the characterization of peptides. PMID:25599104

  12. 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.

  13. Vapor-liquid phase separator studies

    NASA Technical Reports Server (NTRS)

    Yuan, S. W. K.; Hepler, W. A.; Frederking, T. H. K.

    1985-01-01

    A study of porous plug use for vapor-liquid phase seperation in spaceborne cryogenic systems was conducted. The three main topics addressed were: (1) the usefulness of porous media in designs that call for variable areas and flow rates; (2) the possibility of prediction of main parameters of porous plugs for a given material; and (3) prediction of all parameters of the plug, including secondary parameters.

  14. Computational study of porous materials for gas separations

    NASA Astrophysics Data System (ADS)

    Lin, Li-Chiang

    Nanoporous materials such as zeolites, zeolitic imidazolate frameworks (ZIFs), and metal-organic frameworks (MOFs) are used as sorbents or membranes for gas separations such as carbon dioxide capture, methane capture, paraffin/olefin separations, etc. The total number of nanoporous materials is large; by changing the chemical composition and/or the structural topologies we can envision an infinite number of possible materials. In practice one can synthesize and fully characterize only a small subset of these materials. Hence, computational study can play an important role by utilizing various techniques in molecular simulations as well as quantum chemical calculations to accelerate the search for optimal materials for various energy-related separations. Accordingly, several large-scale computational screenings of over one hundred thousand materials have been performed to find the best materials for carbon capture, methane capture, and ethane/ethene separation. These large-scale screenings identified a number of promising materials for different applications. Moreover, the analysis of these screening studies yielded insights into those molecular characteristics of a material that contribute to an optimal performance for a given application. These insights provided useful guidelines for future structural design and synthesis. For instance, one of the screening studies indicated that some zeolite structures can potentially reduce the energy penalty imposed on a coal-fired power plant by as much as 35% compared to the near-term MEA technology for carbon capture application. These optimal structures have topologies with a maximized density of pockets and they capture and release CO2 molecules with an optimal energy. These screening studies also pointed to some systems, for which conventional force fields were unable to make sufficiently reliable predictions of the adsorption isotherms of different gasses, e.g., CO2 in MOFs with open-metal sites. For these systems, we

  15. 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. PMID:27441220

  16. 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.

  17. Fundamental study on magnetic separation of organic dyes in wastewater

    NASA Astrophysics Data System (ADS)

    Fang, M.; Mishima, F.; Akiyama, Y.; Nishijima, S.

    2010-11-01

    The objective of this study is to separate dyes in wastewater with high efficiency and speed using High Gradient Magnetic Separation with superconducting magnet. Two main technologies are necessary for magnetic separation; one is magnetic seeding technology to provide ferromagnetism to the substance, and the other is magnetic separation technology using superconducting magnet and magnetic filters. In order to separate organic dyes, it is necessary to clarify the mechanism of magnetic seeding, and to design a suitable magnetic seeding method depending on the kind of object dye. Six kinds of dyes which are widely used in industry were adopted to investigate the possibility of the magnetic seeding and interaction mechanism between dye and ferromagnetic particles. As a result, it was shown that electrostatic interaction is one of the main interactions between organic dye and ferromagnetic particles.

  18. Synthesis and characterization of novel nitrogen-containing ligands for metal ion separations

    NASA Astrophysics Data System (ADS)

    Hoch, Cortney Leigh

    A serious limiting factor in the continued development of nuclear power is the disposal of high-level radioactive waste from spent nuclear fuel. The PUREX process can be used for the recovery of U and Pu, but it does not separate the products of fission which are potentially useful, but currently cause most of our problems with radioactive waste. An important complicating factor is the presence of large amounts of lanthanides in dissolved spent nuclear fuel. The separation of lanthanides (Ln) from actinides (An) is therefore critical to the future of nuclear power. One approach to recovering these materials and decreasing the volume of the radioactive waste is the development of novel, highly selective organic ligands for the lanthanide and actinide ions. The focus of this dissertation is to design and synthesize new tridentate polyaza-ligands expected to exhibit affinity for first-row transition metals, lanthanides and actinides. In general, these chelating agents are structurally and functionally related to the pyridine and bipyridine bis-triazinyl compounds that have been investigated for potential application as separations agents for radioactive materials. Selected 1,2,3-triazoles have been synthesized using Sharpless' "Click Chemistry". Variation of the backbone and substituents on the triazole ring allows for facile modification of the cation binding pocket and phase compatibility properties of the new compounds. Characterization of the new ligands was performed using conventional analytical methods. Overall, the studies with three different ligands revealed useful information about the continuing effort of ligand design for actinide (III)/lanthanide (III) separations. Crystal structures established the purity of the organic molecules by showing that the PTMP and BDTP ligands are able to bind transition metals. Also, it was shown that the BDTB ligand was able to bind to Nd 3+ as observed from the spectrophotometric titrations and the calculated binding

  19. 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.

  20. 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.…

  1. 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.

  2. Fabrication and characterization of well-aligned plasmonic nanopillars with ultrasmall separations

    PubMed Central

    2014-01-01

    We show the fabrication of well-aligned gold and silver nanopillars with various array parameters via interference lithography followed by ion beam milling and compare the etching rates of these two metallic materials. Silver is suitable for fabricating ultrafine arrays with ultrasmall separations due to high milling rates. The optical properties of the fabricated nanopillars are specifically characterized from both normal incidence and oblique incident angles. Tunable surface plasmon resonances are achieved with varying structural parameters. Strong coupling effects are enabled when the separation between adjacent nanopillars is dramatically reduced, leading to useful applications in sensing and waveguiding. PMID:24959111

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. An improved matrix separation method for characterization of ultrapure germanium (8N).

    PubMed

    Reddy, M A; Shekhar, R; Jai Kumar, Sunil

    2016-10-01

    An improved matrix separation method has been described to characterize ultrapure germanium of 8N (99.999999%) purity. In this method, temperature of the reaction vessel in which in-situ generated chlorine gas reacts with germanium solid material directly is optimized to quantitatively remove Ge matrix from all its impurities. Optimized reaction temperature has been found to be 230±5°C. Recovery studies on more than 60 elements have been carried out at the optimized temperature. Recoveries of all the analytes except As, Se, Sn, Hg, Tl are found to be quantitative. The method has been examined for various amounts of Ge material and found to be suitable even for 10g of Ge sample and provides low parts per billion and trillion levels of process blanks. Determination of concentrations of impurities has been done by inductively coupled plasma quadrupole mass spectrometer (ICP-QMS) and high resolution continuum source graphite furnace atomic absorption spectrometer (HR-CS-GFAAS). In the absence of certified reference materials for ultrapure germanium, accuracy of the proposed method is established by spike recovery tests. Precision of this method is found to vary from 7% to 50% for concentrations between 4 and 0.004ngg(-1). Limits of detection (LOD) for the target analytes are found to be between 6 and 0.011ngmL(-1) or 1.8-0.003ngg(-1) for the proposed procedure. The method has been successfully applied for that characterization of ultrapure germanium material of 8N purity.

  8. An improved matrix separation method for characterization of ultrapure germanium (8N).

    PubMed

    Reddy, M A; Shekhar, R; Jai Kumar, Sunil

    2016-10-01

    An improved matrix separation method has been described to characterize ultrapure germanium of 8N (99.999999%) purity. In this method, temperature of the reaction vessel in which in-situ generated chlorine gas reacts with germanium solid material directly is optimized to quantitatively remove Ge matrix from all its impurities. Optimized reaction temperature has been found to be 230±5°C. Recovery studies on more than 60 elements have been carried out at the optimized temperature. Recoveries of all the analytes except As, Se, Sn, Hg, Tl are found to be quantitative. The method has been examined for various amounts of Ge material and found to be suitable even for 10g of Ge sample and provides low parts per billion and trillion levels of process blanks. Determination of concentrations of impurities has been done by inductively coupled plasma quadrupole mass spectrometer (ICP-QMS) and high resolution continuum source graphite furnace atomic absorption spectrometer (HR-CS-GFAAS). In the absence of certified reference materials for ultrapure germanium, accuracy of the proposed method is established by spike recovery tests. Precision of this method is found to vary from 7% to 50% for concentrations between 4 and 0.004ngg(-1). Limits of detection (LOD) for the target analytes are found to be between 6 and 0.011ngmL(-1) or 1.8-0.003ngg(-1) for the proposed procedure. The method has been successfully applied for that characterization of ultrapure germanium material of 8N purity. PMID:27474273

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

    NASA Astrophysics Data System (ADS)

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

    2016-05-01

    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.

  10. Wall shear stress characterization of a 3D bluff-body separated flow

    NASA Astrophysics Data System (ADS)

    Fourrié, Grégoire; Keirsbulck, Laurent; Labraga, Larbi

    2013-10-01

    Efficient flow control strategies aimed at reducing the aerodynamic drag of road vehicles require a detailed knowledge of the reference flow. In this work, the flow around the rear slanted window of a generic car model was experimentally studied through wall shear stress measurements using an electrochemical method. The mean and fluctuating wall shear stress within the wall impact regions of the recirculation bubble and the main longitudinal vortex structures which develop above the rear window are presented. Correlations allow a more detailed characterization of the recirculation phenomenon within the separation bubble. In the model symmetry plane the recirculation structure compares well with simpler 2D configurations; specific lengths, flapping motion and shedding of large-scale vortices are observed, these similarities diminish when leaving the middle plane due to the strong three-dimensionality of the flow. A specific attention is paid to the convection processes occurring within the recirculation: a downstream convection velocity is observed, in accordance with 2D recirculations from the literature, and an upstream convection is highlighted along the entire bubble length which has not been underlined in some previous canonical configurations.

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

    DOE PAGESBeta

    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.; et al

    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

  12. 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.

  13. 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. PMID:26510005

  14. 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.

  15. Preparation and characterization of composite membrane for high temperature gas separation. Quarterly technical report, December 1, 1996--February 28, 1997

    SciTech Connect

    Ilias, S.; King, F.G.

    1997-12-31

    To develop a new class of permselective inorganic membranes, the authors have identified electroless plating as a potential route to deposit a thin metal film on a porous substrate. Electroless plating is a controlled autocatalytic deposition of continuous film on the surface of a substrate by the interactions of a metal salt and a chemical reducing agent. This method can give thin films of metals, alloys and composites on both conducting and nonconducting surfaces. 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. They plan to characterize the membrane in terms of permeability and selectivity for gas separation. To accomplish the research objective, the project requires three tasks: (1) development of a process for composite membrane formation; (2) characterization of fabricated composite membrane; and (3) development of theoretical model for hydrogen gas separation. During this quarter they extended their single-staged complete-mixing and cross-flow models to design a Two-Unit-Series (TUS), a Two-Stage Counter-Current Recycle Membrane Cascade (CRMC) and a Five-Stage CRMC arrangement. These designs have been used to study the performance of membrane modules for the separation of hydrogen through Palladium-ceramic composite membranes. The results show that for high-selective membrane, the effect of flow arrangement is of no consequence. Multi-staged cascading significantly improve the product purity and product separation.

  16. 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.

  17. Chromatographic selectivity study of 4-fluorophenylacetic acid positional isomers separation.

    PubMed

    Chasse, Tyson; Wenslow, Robert; Bereznitski, Yuri

    2007-07-13

    Unique properties of the fluorine atom stimulate widespread use and development of new organofluorine compounds in agrochemistry, biotechnology and pharmacology applications. However, relatively few synthetic methods exhibit a high degree of fluorination selectivity, which ultimately results in the presence of structurally related fluorinated isomers in the synthetic product. This outcome is undesirable from a pharmaceutical perspective as positional isomers possess different reactivity, biological activity and toxicity as compared to the desired product. It is advantageous to control positional isomers in the early stages of the synthetic process, as rejection and analysis of these isomers will likely become more difficult in later stages. The current work reports the development of a chromatographic analysis of 2- and 3-fluorophenylacetic acid positional isomer impurities in 4-fluorophenylacetic acid (4-FPAA), a building block in the synthesis of an active pharmaceutical ingredient. The method is employed as a part of a Quality by Design Approach to control purity of the starting material in order to eliminate the presence of undesirable positional isomers in the final drug substance. During method development, a wide range of chromatographic conditions and structurally related positional isomer probe molecules were exploited in an effort to gain insight into the specifics of the separation mechanism. For the systems studied it was shown that the choice of organic modifier played a key role in achieving acceptable separation. Further studies encompassed investigation of temperature influence on retention and selectivity of the FPAA isomers separation. Thermodynamic analysis of these data showed that the selectivity of the 2- and 4- fluorophenylacetic acids separation was dominated by an enthalpic process, while the selectivity of the 4- and 3-fluorophenylacetic acids separation was exclusively entropy driven (Delta(DeltaH degrees approximately 0). Studies of

  18. Separation and characterization of forced degradation products of abacavir sulphate by LC-MS/MS.

    PubMed

    Rao, R Nageswara; Vali, R Mastan; Ramachandra, Bondigalla; Raju, S Satyanarayana

    2011-01-25

    Abacavir sulphate was subjected to forced degradation under the conditions of hydrolysis (acid, alkali and neutral), oxidation, photolysis and thermal stress as prescribed by ICH. Eight degradation products were formed and their separation was accomplished on Waters XTerra C₁₈ (250 mm x 4.6 mm, 5 μm) column using 20 mM ammonium acetate:acetonitrile as a mobile phase in gradient elution mode by LC. The degradation products were characterized by LC-MS/MS and its fragmentation pathways were proposed. No previous reports were found in the literature regarding the degradation behavior of abacavir sulphate.

  19. 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.

  20. 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.

  1. Dielectric Barrier Discharge Ionization in Characterization of Organic Compounds Separated on Thin-Layer Chromatography Plates

    PubMed Central

    Cegłowski, Michał; Smoluch, Marek; Babij, Michał; Gotszalk, Teodor; Silberring, Jerzy; Schroeder, Grzegorz

    2014-01-01

    A new method for on-spot detection and characterization of organic compounds resolved on thin layer chromatography (TLC) plates has been proposed. This method combines TLC with dielectric barrier discharge ionization (DBDI), which produces stable low-temperature plasma. At first, the compounds were separated on TLC plates and then their mass spectra were directly obtained with no additional sample preparation. To obtain good quality spectra the center of a particular TLC spot was heated from the bottom to increase volatility of the compound. MS/MS analyses were also performed to additionally characterize all analytes. The detection limit of proposed method was estimated to be 100 ng/spot of compound. PMID:25170762

  2. 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.

  3. 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.

  4. Real-time Shape-based Particle Separation and Detailed In-situ Particle Shape Characterization

    SciTech Connect

    Beranek, Josef; Imre, D.; Zelenyuk, Alla

    2012-02-07

    Particle shape is an important attribute that is very difficult to characterize. We present a new portable system that offers, for the first time, the opportunity to separate particles with different shapes and characterize their chemical and physical properties, including their dynamic shape factors (DSFs) in the transition and free-molecular regimes, with high precision, in-situ, and in real-time. The system uses a new generation aerosol particle mass analyzer (APM) to classify particles based on their masses and transport them to a differential mobility analyzer (DMA) that is used to select particles of one charge, one mass, and one shape. These highly uniform particles are ready for use and/or characterization by any application or analytical tool. We combine APM and DMA with our single particle mass spectrometer, SPLAT II, to form the ADS, and demonstrate its utility to measure in real-time individual particle compositions and vacuum aerodynamic diameters to yield, for each selected shape, particle DSFs in two flow regimes. We apply the ADS to characterize aspherical ammonium sulfate and NaCl particles and show that both particle types have wide distribution of particle shapes with DSFs from nearly 1 to 1.5.

  5. 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.

  6. 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. PMID:26616455

  7. 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

  8. 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. PMID:26051082

  9. 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.

  10. 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. PMID:22835506

  11. 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.

  12. Characterization of low-temperature cofired ceramic tiles as platforms for gas chromatographic separations.

    PubMed

    Darko, Ernest; Thurbide, Kevin B; Gerhardt, Geoff C; Michienzi, Joseph

    2013-06-01

    A gas chromatography (GC) column is fabricated within a low-temperature cofired ceramic (LTCC) tile, and its analytical properties are characterized. By using a dual-spiral design, a 100 μm wide square channel up to 15 m in length is produced within an 11 cm × 5.5 cm LTCC tile. The channel is dynamically coated with an OV-101 stationary phase that is cross-linked with dicumyl peroxide. While the uncoated LTCC tiles were able to separate a mixture of n-alkanes, the peak shapes were broad (base width of ~2 min) and tailing. In contrast to this, the coated LTCC tiles produced sharp (base width of ~8-10 s), symmetrical, well-resolved peaks for the same analytes. By using a 7.5 m long channel, about 15,000 plates were obtained for a dodecane test analyte. Further, the coated LTCC tiles were found to produce plate heights that were about 3-fold smaller than those obtained from a conventional capillary GC column of similar length, dimension, and coating operated under the same conditions. As a result, test analyte separations were slightly improved in the LTCC tiles, and their overall performance fared well. In terms of temperature programming, it was found that a series of n-alkanes separated on the LTCC tile provided a cumulative peak capacity of around 54 peaks when using C₈ to C₁₃ as analyte markers. Results indicate that LTCC tiles provide a viable and useful alternative platform for performing good quality GC separations.

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

    SciTech Connect

    Russell, Kellie R.; Carlsson Tedgren, Aasa K.; Ahnesjoe, Anders

    2005-09-15

    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 {sup 192}Ir 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

  14. 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.

  15. 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

    2013-01-01

    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. PMID:23447009

  16. 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.

  17. 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.

  18. Characterization of enhanced-fluidity liquid hydrophilic interaction chromatography for the separation of nucleosides and nucleotides.

    PubMed

    Philibert, Gwenaëlle S; Olesik, Susan V

    2011-11-11

    Hydrophilic interaction chromatography (HILIC) is a liquid chromatographic separation mechanism commonly used for polar biological molecules. The use of enhanced-fluidity liquid chromatography (EFLC) with mixtures of methanol/water/carbon dioxide is compared to acetonitrile/water mobile phases for the separation of nucleosides and nucleotides under HILIC conditions. Enhanced-fluidity liquid chromatography involves using common mobile phases with the addition of substantial proportions of a dissolved gas which provides greater mobile phase diffusivity and lower viscosity. The impact of varying several experimental parameters, including temperature, addition of base, salt, and CO₂ was studied to provide optimized HILIC separations. Each of these parameters plays a key role in the retention of the analytes, which demonstrates the complexity of the retention mechanism in HILIC. The tailing of phosphorylated compounds was overcome with the use of phosphate salts and the addition of a strong base; efficiency and peak asymmetry were compared with the addition of either triethylamine (TEA), 1,4-diazabicyclo [2.2.2] octane (DABCO) or 1,5-diazabicyclo [4.3.0] non-5-ene (DBN). DBN and DABCO both led to increased efficiency and lower peak asymmetry; DBN provided the best results. Sodium chloride and carbon dioxide were added to enhance the selectivity between the analytes, giving a successful isocratic separation of nucleosides and nucleotides within 8 min. The retention mechanism involved in EFL-HILIC was explored by varying the temperature and the mole fraction of CO₂. These studies showed that partitioning was the dominant mechanism. The thermodynamics study confirmed that the solvent strength is maintained in EFLC and that a change in entropy was mainly responsible for the improved selectivity. The selectivity using methanol/water/carbon dioxide varied greatly compared to that obtained with acetonitrile/water. Finally while this study highlights the optimization of EFL

  19. Blending Study of MgO-Based Separator Materials for Thermal Batteries

    SciTech Connect

    GUIDOTTI, RONALD A.; REINHARDT, FREDERICK W.; ANDAZOLA, ARTHUR H.

    2002-06-01

    The development and testing of a new technique for blending of electrolyte-binder (separator) mixes for use in thermal batteries is described. The original method of blending such materials at Sandia involved liquid Freon TF' as a medium. The ban on the use of halogenated solvents throughout much of the Department of Energy complex required the development of an alternative liquid medium as a replacement. The use of liquid nitrogen (LN) was explored and developed into a viable quality process. For comparison, a limited number of dry-blending tests were also conducted using a Turbula mixer. The characterization of pellets made from LN-blended separators involved deformation properties at 530 C and electrolyte-leakage behavior at 400 or 500 C, as well as performance in single-cells and five-cell batteries under several loads. Stack-relaxation tests were also conducted using 10-cell batteries. One objective of this work was to observe if correlations could be obtained between the mechanical properties of the separators and the performance in single cells and batteries. Separators made using three different electrolytes were examined in this study. These included the LiCl-KCl eutectic, the all-Li LiCl-LiBr-LiF electrolyte, and the low-melting LiBr-KBr-LiF eutectic. The electrochemical performance of separator pellets made with LN-blended materials was compared to that for those made with Freon T P and, in some cases, those that were dry blended. A satisfactory replacement MgO (Marinco 'OL', now manufactured by Morton) was qualified as a replacement for the standard Maglite 'S' MgO that has been used for years but is no longer commercially available. The separator compositions with the new MgO were optimized and included in the blending and electrochemical characterization tests.

  20. 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

  1. 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.

  2. Rapid Separation Methods to Characterize Actinides and Metallic Impurities in Plutonium Scrap Materials at SRS

    SciTech Connect

    Maxwell, S.L. III; Jones, V.D.

    1998-07-01

    The Nuclear Materials Stabilization and Storage Division at SRS plans to stabilize selected plutonium scrap residue materials for long term storage by dissolution processing and plans to stabilize other plutonium vault materials via high-temperature furnace processing. To support these nuclear material stabilization activities, the SRS Analytical Laboratories Department (ALD) will provide characterization of materials required prior to the dissolution or the high-firing of these materials. Lab renovations to install new analytical instrumentation are underway to support these activities that include glove boxes with simulated-process dissolution and high- pressure microwave dissolution capability. Inductively-coupled plasma atomic emission spectrometry (ICP-AES), inductively- coupled mass spectrometry (ICP-MS) and thermal-ionization mass spectrometry (TIMS) will be used to measure actinide isotopics and metallic impurities. New high-speed actinide separation methods have been developed that will be applied to isotopic characterization of nuclear materials by TIMS and ICP-MS to eliminate isobaric interferences between Pu-238 /U- 238 and Pu-241/Am-241. TEVA Resin, UTEVA Resin, and TRU Resin columns will be used with vacuum-assisted flow rates to minimize TIMS and ICP-MS sample turnaround times. For metallic impurity analysis, rapid column removal methods using UTEVA Resin, AGMP-1 anion resin and AG MP-50 cation resin have also been developed to remove plutonium and uranium matrix interferences prior to ICP-AES and ICP- MS measurements.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Experimental study of airfoil separation control using synthetic jets

    NASA Astrophysics Data System (ADS)

    Xia, Xi; Mohseni, Kamran

    2010-11-01

    The flow control over an airfoil is studied experimentally in a wind tunnel. Synthetic jets are placed on the top surface of the airfoil as flow actuators. The position and the angle of the jet orifice, together with the frequency and jet strength could be varied in order to adjust the separation or reattachment points on the surface. An Array of hot-film sensors are located on the surface in order to detect the location of the reattachment point. The airfoil is mounted on a 6 d.o.f force balance system to dynamically measure the drag and lift forces on the airfoil. Results from the hot-film sensor array measurement are correlated to the measured drag and lift forces.

  8. Phase separated membrane bioreactor: Results from model system studies

    NASA Astrophysics Data System (ADS)

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

    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.

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

    NASA Astrophysics Data System (ADS)

    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 (ℓeq) in the steady state suggests a power-law dependence on the reaction rate ɛ :ℓeq˜ɛ-θ with θ ≃1.0 .

  10. 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.

  11. Preparation and Char Characterization of Composite Membrane for High Temperature Gas Separation.

    SciTech Connect

    Illias, S.; King, F.G.

    1997-07-31

    A palladium-ceramic composite membrane was developed by electroless deposition of palladium on microporous ceramic substrate. By measuring the permeation characteristics of pure and mixed gases, it was found that the new membrane has a very high permeability and selectivity for hydrogen. During this reporting period, a concurrent flow model for a membrane module was developed to study the performance of palladium-ceramic composite membranes for hydrogen separation in terms of product purity under various operating conditions. The model neglects mass transfer resistance but it was found that the difference between the predicted and actual hydrogen composition was less than 12%.

  12. 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. PMID:26876843

  13. Protein separation and characterization by np-RP-HPLC followed by intact MALDI-TOF mass spectrometry and peptide mass mapping analyses.

    PubMed

    Dauly, Claire; Perlman, David H; Costello, Catherine E; McComb, Mark E

    2006-07-01

    Because of their complexity, the separation of intact proteins from complex mixtures is an important step to comparative proteomics and the identification and characterization of the proteins by mass spectrometry (MS). In the study reported, we evaluated the use of nonporous-reversed-phase (np-RP)-HPLC for intact protein separation prior to MS analyses. The separation system was characterized and compared to 1D-SDS-PAGE electrophoresis in terms of resolution and sensitivity. We demonstrate that np-RP-HPLC protein separation is highly reproducible and provides intact protein fractions which can be directly analyzed by MALDI-TOF-MS for intact molecular weight determination. An in-well digestion protocol was developed, allowing for rapid protein identification by peptide mass fingerprinting (PMF) and resulted in comparable or improved peptide recovery compared with in-gel digestion. The np-RP sensitivity of detection by UV absorbance at 214 nm for intact proteins was at the low ng level and the sensitivity of peptide analysis by MALDI-TOF-MS was in the 10-50 fmol level. A membrane protein fraction was characterized to demonstrate application of this methodology. Among the identified proteins, multiple forms of vimentin were observed. Overall, we demonstrate that np-RP-HPLC followed by MALDI-TOF-MS allows for rapid, sensitive, and reproducible protein fractionation and very specific protein characterization by integration of PMF analysis with MS intact molecular weight information.

  14. Separation and partial characterization of two deoxyribonucleic acid polymerases from Spiroplasma citri.

    PubMed Central

    Charron, A; Bebear, C; Brun, G; Yot, P; Latrille, J; Bove, J M

    1979-01-01

    The separation and partial characterization of two deoxyribonucleic acid polymerases from Spiroplasma citri have been achieved. The two enzymes had different elution properties on diethylaminoethyl (DEAE) cellulose and differed in their sensitivity to N-ethylmaleimide (NEM), preference for different template-primers, and sedimentation velocity in linear glycerol gradients. The first enzyme activity, ScA, was retained on DEAE-cellulose and was not inhibited by NEM. Activated deoxyribonucleic acid and poly(dA)-oligo(dT12) were the preferred template-primers. Arabinosyl-cytidine triphosphate had no effect. The sedimentation coefficient of ScA was 6.3s. The second activity, ScB, was not retained on DEAE-cellulose and was inhibited by NEM. Poly(dA)-oligo(dT12) was the preferred template-primer, whereas activated DNA was only poorly utilized. ScB was not affected by arabinosyl-cytidine triphosphate, and its sedimentation coefficient was 4.4s. The polymerization activities of the two enzymes were maximum at 37 to 40 degrees C. PMID:42638

  15. Separation of inner and outer membranes of Rickettsia prowazeki and characterization of their polypeptide compositions.

    PubMed Central

    Smith, D K; Winkler, H H

    1979-01-01

    Rickettsia prowazeki were disrupted in a French pressure cell and fractionated into soluble (cytoplasm) and envelope fractions. The envelope contained 25% of the cell protein, with the cytoplasm containing 75%. Upon density gradient centrifugation, the envelope fraction separated into a heavy band (1.23 g/cm3) and a lighter band (1.19 g/cm3). The heavy band had a high content of 2-keto-3-deoxyoctulosonic acid, a marker for bacterial lipopolysaccharide, but had no succinic dehydrogenase, a marker for cytoplasmic membrane activity, and therefore represented outer membrane. The lighter band exhibited a high succinate dehydrogenase activity, and thus contained inner (cytoplasmic) membrane. Outer membrane purified by this method was less than 5% contaiminated by cytoplasmic membrane; however, inner membrane from the gradient was as much as 30% contaminated by outer membrane. The protein composition of each cellular fraction was characterized by sodium dodecyl sulfate--polyacrylamide gel electrophoresis. The outer membrane contained four major proteins, which were also major proteins of the whole cell. The cytoplasmic membrane and soluble cytoplasm exhibited a more complex pattern on gels. Images PMID:106046

  16. 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

  17. 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.

  18. 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

  19. Bio-electrochemical characterization of air-cathode microbial fuel cells with microporous polyethylene/silica membrane as separator.

    PubMed

    Kircheva, Nina; Outin, Jonathan; Perrier, Gérard; Ramousse, Julien; Merlin, Gérard; Lyautey, Emilie

    2015-12-01

    The aim of this work was to study the behavior over time of a separator made of a low-cost and non-selective microporous polyethylene membrane (RhinoHide®) in an air-cathode microbial fuel cell with a reticulated vitreous carbon foam bioanode. Performances of the microporous polyethylene membrane (RhinoHide®) were compared with Nafion®-117 as a cationic exchange membrane. A non-parametric test (Mann-Whitney) done on the different sets of coulombic or energy efficiency data showed no significant difference between the two types of tested membrane (p<0.05). Volumetric power densities were ranging from 30 to 90 W·m(-3) of RVC foam for both membranes. Similar amounts of biomass were observed on both sides of the polyethylene membrane illustrating bacterial permeability of this type of separator. A monospecific denitrifying population on cathodic side of RhinoHide® membrane has been identified. Electrochemical impedance spectroscopy (EIS) was used at OCV conditions to characterize electrochemical behavior of MFCs by equivalent electrical circuit fitted on both Nyquist and Bode plots. Resistances and pseudo-capacitances from EIS analyses do not differ in such a way that the nature of the membrane could be considered as responsible.

  20. 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

  1. Development and characterization of silica tube-coated separator for lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Zhang, Peng; Chen, Lixiao; Shi, Chuan; Yang, Pingting; Zhao, Jinbao

    2015-06-01

    In an endeavor to improve the thermal stability of lithium-ion batteries (LIBs), a new kind of ceramic coated separator has been developed based on introducing one-dimensional silica tubes (ST) to one side of a commercial polyethylene (PE) porous separator. The ST interpenetrating network diminishes the thermal-induced dimensional change of the commercial separator without compromising the cell performance. In particular, compared to spherical silica particle (SP) coated separator, the ST coated separator exhibits significantly enhanced thermal stability at elevated temperature. Furthermore the ST coated separator shows better mechanical performance as well as the improved electrolyte absorption and retention behavior, which provides a promising solution to replace conventional polymer separator for high-performance LIBs.

  2. 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.

  3. 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.

  4. 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…

  5. Equivalent peak resolution: characterization of the extent of separation for two components based on their relative peak overlap.

    PubMed

    Dvořák, Martin; Svobodová, Jana; Dubský, Pavel; Riesová, Martina; Vigh, Gyula; Gaš, Bohuslav

    2015-03-01

    Although the classical formula of peak resolution was derived to characterize the extent of separation only for Gaussian peaks of equal areas, it is often used even when the peaks follow non-Gaussian distributions and/or have unequal areas. This practice can result in misleading information about the extent of separation in terms of the severity of peak overlap. We propose here the use of the equivalent peak resolution value, a term based on relative peak overlap, to characterize the extent of separation that had been achieved. The definition of equivalent peak resolution is not constrained either by the form(s) of the concentration distribution function(s) of the peaks (Gaussian or non-Gaussian) or the relative area of the peaks. The equivalent peak resolution value and the classically defined peak resolution value are numerically identical when the separated peaks are Gaussian and have identical areas and SDs. Using our new freeware program, Resolution Analyzer, one can calculate both the classically defined and the equivalent peak resolution values. With the help of this tool, we demonstrate here that the classical peak resolution values mischaracterize the extent of peak overlap even when the peaks are Gaussian but have different areas. We show that under ideal conditions of the separation process, the relative peak overlap value is easily accessible by fitting the overall peak profile as the sum of two Gaussian functions. The applicability of the new approach is demonstrated on real separations.

  6. 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

  7. Synthesis, Separation, and Characterization of Small and Highly Fluorescent Nitrogen-Doped Carbon NanoDots.

    PubMed

    Arcudi, Francesca; Đorđević, Luka; Prato, Maurizio

    2016-02-01

    A facile bottom-up approach to carbon nanodots (CNDs) is reported, using a microwave-assisted procedure under controlled conditions. The as-prepared nitrogen-doped CNDs (NCNDs) show narrow size-distribution, abundant surface traps and functional groups, resulting in tunable fluorescent emission and excellent solubility in water. Moreover, we present a general method for the separation of NCNDs by low-pressure size-exclusion chromatography, leading to an even narrower size distribution, different surface composition, and optical properties. They display among the smallest size and the highest FLQYs reported so far. (13)C-enriched starting materials produced N(13) CNDs suitable for thorough NMR studies, which gave useful information on their molecular structure. Moreover, they can be easily functionalized and can be used as water-soluble carriers. This work provides an avenue to size- and surface-controllable and structurally defined NCNDs for applications in areas such as optoelectronics, biomedicine, and bioimaging. PMID:26733058

  8. 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.

  9. 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

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

    PubMed

    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

  11. 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

  12. A numerical study of separation on a spheroid at incidence

    NASA Technical Reports Server (NTRS)

    Rosenfeld, M.; Israeli, M.; Wolfshtein, M.

    1986-01-01

    The three-dimensional incompressible, steady and laminar flow field around a prolate spheroid at incidence is considered. The parabolized Navier-Stokes equations are solved numerically. The method can handle vortex types as well as bubble type flow separation because the pressure is one of the dependent variables. Here, the distribution of the skin friction is reported for two test cases. The first test case is a prolate spheroid of aspect ratio of 4:1 at 6 degrees incidence and Reynolds number of 1 million (based on half the major axis). The second case is a spheroid with a 6:1 aspect ratio at 10 degrees incidence and Reynolds number of 0.8 x 1 million. The properties of the flow field near the body are discussed on the basis of the pattern of the skin friction lines, and the shape of the separation lines. Favorable agreement with experimental results is obtained.

  13. Separation and characterization of coal derived components. Quarterly report, 1 October 1983-31 December 1983

    SciTech Connect

    Hurtubise, R.H.; Silver, H.F.

    1984-01-16

    No new field-ionization data was obtained this quarter. For preasphaltenes, elemental analysis data was obtained on Kentucky and Wyodak preasphaltene samples. In conjunction with the preasphaltene work, solubility and thin-layer chromatography experiments were performed. The results indicated that basic alumina would not be useful as a general stationary phase for the separation of preasphaltenes. Several experiments were carried out with Chromasorb T, and the results showed it would be an adequate substitute for Fluoropak. The hydrocarbons in a sample from Pittsburgh Energy Technology Center were separated by the number of double bonds. The optimum mobile phases for the separation of monohydroxyl aromatics and dihydroxyl aromatics by reversed-phase liquid chromatography were obtained. In addition, a means of predicting retention in normal-phase chromatography was considered, and a NO/sub 2/ high-performance chromatographic column showed promise for the separation of compound classes. 6 references, 4 figures, 7 tables.

  14. 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…

  15. Separation and Partial Characterization of Two Ribonucleic Acid Polymerases from Pea Seedlings 1

    PubMed Central

    Glicklich, Daniel; Jendrisak, Jerome J.; Becker, Wayne M.

    1974-01-01

    Two DNA-dependent RNA polymerases (ribonucleoside triphosphate:RNA nucleotidyl transferase, EC 2.7.7.6) have been isolated from pea (Pisum sativum) seedlings. The enzymes were solubilized by sonication in high salt buffer and were separated by chromatography on diethylaminoethyl cellulose using a linear salt gradient. Polymerase I eluted at 0.10 m (NH4)2SO4, accounted for about 10% of the recovered activity and was completely insensitive to α-amanitin. Polymerase II eluted at 0.14 m (NH4)2SO4, accounted for the remaining 90% of recovered activity and was strongly inhibited by α-amanitin. Both enzymes preferred denatured to native DNA as template, both showed an absolute requirement of divalent cation, and both were sensitive to the ionic strength of the assay medium. The developing pea seedling seems a promising system for studies of possible changes in relative activities and roles of multiple RNA polymerases during eukaryotic development. PMID:16658887

  16. Separation and characterization of oxaliplatin dinucleotides from DNA using HPLC-ESI ion trap mass spectrometry.

    PubMed

    Mowaka, Shereen; Linscheid, Michael

    2008-11-01

    Oxaliplatin is a third-generation platinum complex, and has a broad spectrum of antitumor activity. Such platinum complexes with the DACH carrier ligand have recently received increasing attention since they show efficacy against cisplatin-resistant cell lines. As the foremost indication of antitumor activity of platinum drugs is the formation of adducts with genomic DNA, calf thymus DNA-oxaliplatin adducts were the major target in this study. Calf thymus DNA was incubated with oxaliplatin, resulting in the formation of a large number of platinum-DNA adducts. Treated DNA was digested into the dinucleotides with a combination of enzymes, namely, benzonase, alkaline phosphatase, and nuclease S1. Using a high-performance liquid chromatography, we carried out the separation of individual platinum-DNA adducts which were concurrently identified using electrospray ionization ion trap mass spectrometry (MS). Both 1,2-intrastrand and 1,2-interstrand cross-linked adducts were found; however, those of the intrastrand nature have a considerably higher abundance than those of the interstrand cross-links. Among them, d(GpG)-oxaliplatin was the most abundant bifuctional adduct. To a lesser extent, a few monofunctional adducts were detected as well. MS(n) experiments served to ascertain the detailed structures of oxaliplatin adducts of dinucleoside monophosphates and of dinucleotides.

  17. Fuels characterization studies. [jet fuels

    NASA Technical Reports Server (NTRS)

    Seng, G. T.; Antoine, A. C.; Flores, F. J.

    1980-01-01

    Current analytical techniques used in the characterization of broadened properties fuels are briefly described. Included are liquid chromatography, gas chromatography, and nuclear magnetic resonance spectroscopy. High performance liquid chromatographic ground-type methods development is being approached from several directions, including aromatic fraction standards development and the elimination of standards through removal or partial removal of the alkene and aromatic fractions or through the use of whole fuel refractive index values. More sensitive methods for alkene determinations using an ultraviolet-visible detector are also being pursued. Some of the more successful gas chromatographic physical property determinations for petroleum derived fuels are the distillation curve (simulated distillation), heat of combustion, hydrogen content, API gravity, viscosity, flash point, and (to a lesser extent) freezing point.

  18. Chromatographic characterization of hydrophilic interaction liquid chromatography stationary phases: hydrophilicity, charge effects, structural selectivity, and separation efficiency.

    PubMed

    Kawachi, Yuusuke; Ikegami, Tohru; Takubo, Hirotaka; Ikegami, Yuka; Miyamoto, Masatoshi; Tanaka, Nobuo

    2011-09-01

    Fourteen commercially available particle-packed columns and a monolithic column for hydrophilic interaction liquid chromatography (HILIC) were characterized in terms of the degree of hydrophilicity, the selectivity for hydrophilic-hydrophobic substituents, the selectivity for the regio and configurational differences in hydrophilic substituents, the selectivity for molecular shapes, the evaluation of electrostatic interactions, and the evaluation of the acidic-basic nature of the stationary phases using nucleoside derivatives, phenyl glucoside derivatives, xanthine derivatives, sodium p-toluenesulfonate, and trimethylphenylammonium chloride as a set of samples. Principal component analysis based on the data of retention factors could separate three clusters of the HILIC phases. The column efficiency and the peak asymmetry factors were also discussed. These data on the selectivity for partial structural differences were summarized as radar-shaped diagrams. This method of column characterization is helpful to classify HILIC stationary phases on the basis of their chromatographic properties, and to choose better columns for targets to be separated. Judging from the retention factor for uridine, these HILIC columns could be separated into two groups: strongly retentive and weakly retentive stationary phases. Among the strongly retentive stationary phases, zwitterionic and amide functionalities were found to be the most selective on the basis of partial structural differences. The hydroxyethyl-type stationary phase showed the highest retention factor, but with low separation efficiency. Weakly retentive stationary phases generally showed lower selectivity for partial structural differences. PMID:21782195

  19. 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…

  20. 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.

  1. 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

  2. Synthesis and gas separation studies of substituted polyaniline membranes

    SciTech Connect

    Su, T.M.; Kwon, A.H.; Lew, B.M.; Kaner, R.B.

    1996-10-01

    Polyaniline is a conjugated polymer that can be reversibly doped and undoped using common acids and bases. In the doped state, polyaniline is thermally and environmentally stable and electrically conducting. Polyaniline has shown promise as a gas separation membrane, however, it is limited by poor thermal processability and solvent solubility. The solvent solubility is increased for ethyl and methoxy substituted polyaniline. The smooth free-standing membranes cast from these substituted polymers exhibit an increase in gas permeability compared to the base form of polyaniline, but a decrease in selectivity.

  3. Preparation and characterization of brush-like PEGMA-graft-PDA coating and its application for protein separation by CE.

    PubMed

    Chen, Lijuan; Liu, Guangming; Liu, Songtao; Bai, Longchao; Wang, Yanmei

    2014-01-01

    In this paper, a novel brush-like copolymer consisting of poly(ethylene glycol) methyl ether methacrylate and 2-aminoethyl methacrylate (AEMA) named as poly(PEGMA300-co-AEMA) was synthesized by atom transfer radical polymerization (ATRP), and then, poly(PEGMA300-co-AEMA) copolymer was immobilized onto material surfaces through polydopamine (PDA)-anchored coating. The defined copolymer structure was characterized by nuclear magnetic resonance hydrogen spectroscopy ((1)H NMR) and gel permeation chromatography (GPC). The chemical component and surface morphology of the brush-like copolymer-graft-PDA coating were studied by using X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM), respectively. The hydrophilicity of the brush-like copolymer-graft-PDA coating was investigated by using static water contact angle. The protein-resistant property of the brush-like copolymer-graft-PDA coating was investigated by using quartz crystal microbalance with dissipation (QCM-D), and finally the coating was applied to capillary inner surface for protein separation by capillary electrophoresis (CE).

  4. 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.

  5. 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. PMID:26354688

  6. Magnetic microgels, a promising candidate for enhanced magnetic adsorbent particles in bioseparation: synthesis, physicochemical characterization, and separation performance.

    PubMed

    Turcu, Rodica; Socoliuc, Vlad; Craciunescu, Izabell; Petran, Anca; Paulus, Anja; Franzreb, Matthias; Vasile, Eugeniu; Vekas, Ladislau

    2015-02-01

    For specific applications in the field of high gradient magnetic separation of biomaterials, magnetic nanoparticle clusters of controlled size and high magnetic moment in an external magnetic field are of particular interest. We report the synthesis and characterization of magnetic microgels designed for magnetic separation purposes, as well as the separation efficiency of the obtained microgel particles. High magnetization magnetic microgels with superparamagnetic behaviour were obtained in a two-step synthesis procedure by a miniemulsion technique using highly stable ferrofluid on a volatile nonpolar carrier. Spherical clusters of closely packed hydrophobic oleic acid-coated magnetite nanoparticles were coated with cross linked polymer shells of polyacrylic acid, poly-N-isopropylacrylamide, and poly-3-acrylamidopropyl trimethylammonium chloride. The morphology, size distribution, chemical surface composition, and magnetic properties of the magnetic microgels were determined using transmission electron microscopy, X-ray photoelectron spectroscopy, and vibrating sample magnetometry. Magnetically induced phase condensation in aqueous suspensions of magnetic microgels was investigated by optical microscopy and static light scattering. The condensed phase consists of elongated oblong structures oriented in the direction of the external magnetic field and may grow up to several microns in thickness and tens or even hundreds of microns in length. The dependence of phase condensation magnetic supersaturation on the magnetic field intensity was determined. The experiments using high gradient magnetic separation show high values of separation efficiency (99.9-99.97%) for the magnetic microgels. PMID:25519891

  7. 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.

  8. Spectro-microscopic Characterization of Physical Properties and Phase Separations in Individual Atmospheric Particles

    NASA Astrophysics Data System (ADS)

    OBrien, R. E.; Wang, B.; Neu, A.; Kelly, S. T.; Lundt, N.; Epstein, S. A.; MacMillan, A.; You, Y.; Laskin, A.; Nizkorodov, S.; Bertram, A. K.; Moffet, R.; Gilles, M.

    2013-12-01

    The phase state and liquid-liquid phase separations of ambient and laboratory generated aerosol particles were investigated using (1) scanning transmission x-ray microscopy/near-edge x-ray absorption fine structure spectroscopy (STXM/NEXAFS) coupled to a relative humidity (RH) controlled in-situ chamber and (2) environmental scanning electron microscopy (ESEM). The phase states of the particles were determined from measurements of their size and optical density. A comparison is made between the observed phase states of ambient samples and of laboratory generated aerosols to determine how well laboratory samples represent the phase of ambient samples. In addition, liquid-liquid phase separations in laboratory generated particles were investigated. Preliminary results showing that liquid-liquid phase separations occur at RH's between the deliquescence and efflorescence points and that the organic phase surrounds the inorganic phase will be presented. The STXM/NEXAFS technique provides insight into the degree of mixing at the deliquescence point and the degree of phase separation for particles of atmospherically relevant sizes.

  9. 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.

  10. Preparation and characterization of chemically functionalized silica-coated magnetic nanoparticles as a DNA separator.

    PubMed

    Kang, Kiho; Choi, Jinsub; Nam, Joong Hee; Lee, Sang Cheon; Kim, Kyung Ja; Lee, Sang-Won; Chang, Jeong Ho

    2009-01-15

    The work describes a simple and convenient process for highly efficient and direct DNA separation with functionalized silica-coated magnetic nanoparticles. Iron oxide magnetic nanoparticles and silica-coated magnetic nanoparticles were prepared uniformly, and the silica coating thickness could be easily controlled in a range from 10 to 50 nm by changing the concentration of silica precursor (TEOS) including controlled magnetic strength and particle size. A change in the surface modification on the nanoparticles was introduced by aminosilanization to enhance the selective DNA separation resulting from electrostatic interaction. The efficiency of the DNA separation was explored via the function of the amino-group numbers, particle size, the amount of the nanoparticles used, and the concentration of NaCl salt. The DNA adsorption yields were high in terms of the amount of triamino-functionalized nanoparticles used, and the average particle size was 25 nm. The adsorption efficiency of aminofunctionalized nanoparticles was the 4-5 times (80-100%) higher compared to silica-coated nanoparticles only (10-20%). DNA desorption efficiency showed an optimum level of over 0.7 M of the NaCl concentration. To elucidate the agglomeration of nanoparticles after electrostatic DNA binding, the Guinier plots were calculated from small-angle X-ray diffractions in a comparison of the results of energy diffraction TEM and confocal laser scanning microscopy. Additionally, the direct separation of human genomic DNA was achieved from human saliva and whole blood with high efficiency.

  11. 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. PMID:26827017

  12. 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.

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

    NASA Astrophysics Data System (ADS)

    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.

  14. Morphological and molecular characterization of separated pelagic eggs from Lophius litulon (Lophiiformes; Lophiidae).

    PubMed

    Oh, J; Kim, S

    2015-06-01

    Free-floating eggs of Lophius litulon were collected using plankton nets after their release from a pelagic egg mass. The eggs were identified based on molecular analysis and several morphological characteristics. These rare, separated eggs have not been reported previously and represent the first such finding for Lophiiformes. PMID:25943592

  15. Deformation study of separator pellets for thermal batteries

    SciTech Connect

    Guidotti, R.A.; Reinhardt, F.W.; Thomas, E.V.

    1995-05-01

    The deformation characteristics of pellets of electrolyte-binder (EB) mixes based on MgO were measured under simulated, thermal-battery conditions. Measurements (using a statistically designed experimental strategy) were made as a function of applied pressure, temperature, and percentage of theoretical density for four molten-salt electrolytes at two levels of MgO. The EB mixes are used as separators in Li-alloy thermal batteries. The electrolytes included LiCl-KCI eutectic, LiCl-LiBr-KBr eutectic, LiBr-KBr-LiF eutectic, and a LiCl-LiBr-LiF electrolyte with a minimum-melting composition. The melting points ranged from 313 C to 436 C. The experimental data were used to develop statistical models that approximate the deformation behavior of pellets of the various EB mixes over the range of experimental conditions we examined. This report, discusses the importance of the deformation response surfaces to thermal-battery design.

  16. Computer simulation study of phase separation in a binary mixture with a glass-forming component

    NASA Astrophysics Data System (ADS)

    Sappelt, Dirk; Jäckle, Josef

    1997-02-01

    We present a computer simulation study of spinodal decomposition with one of the two phases freezing in a glassy state during phase separation. As a model we used the Cahn-Hilliard equation with a concentration-dependent mobility coefficient which decreases rapidly with increasing concentration of the glass-forming component. We solved the Cahn-Hilliard equation numerically for two dimensions. The domain growth depends crucially on the volume fraction of the glassy phase. For high volume fractions, when the glassy phase forms a percolating matrix, a novel coarsening mechanism is discovered, which arises from the migration and coalescence of liquid droplets within the glassy matrix. Various quantities characterizing the time-dependent domain pattern, like droplet size distribution, one- and two-point distribution function and structure factor of the concentration field, are computed. We checked the validity of the dynamic scaling hypothesis.

  17. Platelet contractile proteins: separation and characterization of the actin and myosin-like components.

    PubMed

    Cove, D H; Crawford, N

    1975-01-01

    Solution of thrombosthenin, the contractile protein complex isolated from pig platelets, have been studied by analytical ultracentrifugation and zone sedimentation in sucrose density gradients. Freshly prepared thrombosthenin in 0.6 M KCl shows a prominent peak in the ultracentrifuge with S degrees 20w about 5.5 and higher molecular weight aggregates (greater than 100S) sedimenting quickly to the bottom of the cell. Short term storage of high ionic strength solutions of thrombosthenin induces actomyosin-like gel formation and these gels dissociate with ATP and Mg2+ ions into two components of S degrees 20w 8.0 and S degrees 20w50. The supernatant, after actomyosin gel removal, contains only the S degrees 20w5.5 protein. From results of Ca2+ ATPase activity measurements and SDS polyacrylamide gel electrophoretic mobilities of dissociated thrombosthenin separated into fractions in sucrose density gradients, it is concluded that the S degrees20w5.5 protein species is the myosin-like protein of thrombosthenin. The S degrees 20w8.0 protein is not fibrinogen but also has myosin-like properties and is believed to be myosin dimer. Species of higher S values seen in the presence of ATP and Mg2+ in the analytical ultracentrifuge and located in the higher density zones of the sucrose gradients all gave in SDS polyacrylamide gel electrophoresis a single band of molecular weight 46-47,000 daltons. These subunit proteins appear to be derived from a range of polymeric variants of the F-actin-like protein of the contractile complex. All these higher density F-actin-like proteins readily form superprecipitates and display syneresis when combined with rabbit skeletal muscle myosin or platelet myosin. They are also all capable of conferring upon these two myosins a Mg2+ activated ATPase activity. It is suggested that in thrombosthenin solutions a myosin monomer-dimer equilibrium state exists which can be directionally influenced by a number of factors. The coexistence in the solution

  18. Preparation and characterization of composite membrane for high temperature gas separation. Quarterly technical report, September 1--November 30, 1994

    SciTech Connect

    Ilias, S.; King, F.G.

    1994-12-31

    To develop a new class of permselective inorganic membranes, the authors have identified electroless plating as a potential route to deposit a thin metal film on a porous substrate. Electroless plating is a controlled autocatalytic deposition of continuous film on the surface of a substrate by the interactions of a metal salt and a chemical reducing agent. This method can give thin films of metals, alloys and composites on both conducting and nonconducting surfaces. 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. They plan to 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 formation; Characterization of fabricated composite membrane; and Development of theoretical model for hydrogen gas separation. During this quarter, the authors attempted to measure the diffusivity and permeability of hydrogen gas through the palladium composite membrane. While running the diffusion measurements at elevated temperature and pressure, leakage of hydrogen was observed. This is a serious problem and it needs to be resolved. Currently, they are working on this problem. During this quarter, they also designed a diffusion cell to test thin-film palladium membrane in tubular structure. The diffusion cell is being fabricated and assembled by a local machine shop.

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

    PubMed

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

    2016-02-01

    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.

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

    PubMed

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

    2016-02-01

    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. PMID:26652049

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Separation and characterization of oxidized isomeric lipid-peptide adducts by ion mobility mass spectrometry.

    PubMed

    Milic, Ivana; Kipping, Marc; Hoffmann, Ralf; Fedorova, Maria

    2015-12-01

    Phospholipids are major components of cell membranes and lipoprotein complexes. They are prone to oxidation by endogenous and exogenous reactive oxygen species yielding a large variety of modified lipids including small aliphatic and phospholipid bound aldehydes and ketones. These carbonyls are strong electrophiles that can modify proteins and, thereby, alter their structures and functions triggering various pathophysiological conditions. The analysis of lipid-protein adducts by liquid chromatography-MS is challenged by their mixed chemical nature (polar peptide and hydrophobic lipid), low abundance in biological samples, and formation of multiple isomers. Thus, we investigated traveling wave ion mobility mass spectrometry (TWIMS) to analyze lipid-peptide adducts generated by incubating model peptides corresponding to the amphipathic β1 sheet sequence of apolipoprotein B-100 with 1-palmitoyl-2-(oxo-nonanoyl)-sn-glycerophosphatidylcholine (PONPC). The complex mixture of peptides, lipids, and peptide-lipid adducts was separated by TWIMS, which was especially important for the identification of two mono-PONPC-peptide isomers containing Schiff bases at different lysine residues. Moreover, TWIMS separated structural conformers of one peptide-lipid adduct possessing most likely different orientations of the hydrophobic sn-1 fatty acyl residue and head group of PONPC, relative to the peptide backbone. PMID:26634972

  6. 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.

  7. 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.

  8. 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. PMID:22097022

  9. [Study on recovery of copper from waste printed wiring boards by electrostatic separation].

    PubMed

    Ma, Jun-wei; Wang, Zhen-zhen; Li, Jin-hui

    2006-09-01

    Recovery of Cu from waste printed wiring boards (PWBs) was studied by crushers and electrostatic separator. The results of pulverizing experiment show that liberation degree of metal is higher in grain size -0.9 + 0.074 mm, the product of this grain size can be used as raw material in electrostatic separation. The main factors that influence electrostatic separation are found by dynamic analysis of particles in course of electrostatic separation, it conclude electrode voltage, roller rotate speed, electric coronary polar distance and granularity of particles. The -0.9 + 0.074 mm pulverizing product is separated through single stage electrostatic separation after optimizing influence factors. Result shows that the enrichment condition of Cu in fine material is good, Cu could be concentrated from 32.0% to 63.6%, and recovery ratio is 78.7%.

  10. Separation and Characterization of Two Endopeptidases from Cotyledons of Germinating Vigna mungo Seeds 1

    PubMed Central

    Mitsuhashi, Wataru; Koshiba, Tomokazu; Minamikawa, Takao

    1986-01-01

    Two major endopeptidases were present in cotyledons of germinating Vigna mungo seeds, as detected by the zymogram after polyacrylamide gel electrophoresis. They were not detectable in cotyledons of dry seeds, but their intensities on the zymogram increased during germination. During incubation of detached cotyledons, however, the activities showed only a slight increase for 5 days. These two endopeptidases could be separated by Sephacryl S-200 column chromatography. One of them was found to be a serine-endopeptidase as judged by phenylmethylsulfonylfluoride and diisopropyl fluorophosphate inhibition. The other was a sulfhydryl-endopeptidase because of its dependency on 2-mercaptoethanol and inhibition by leupeptin, chymostatin, and antipain. Analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis indicatd that the two endopeptidases digested the Vigna mungo seed globulin subunits at different rates. The serine enzyme digested the 56 kilodalton subunit at first, but the sulfhydryl enzyme digested the 54 kilodalton peptide more efficiently than the 56 kilodalton peptide. The pattern of digestion of globulin by the combination of the serine- and sulfhydryl-endopeptidases was similar to that using crude enzyme extracts. Images Fig. 2 Fig. 3 Fig. 6 Fig. 7 PMID:16664675

  11. Separation and Characterization of Two Endopeptidases from Cotyledons of Germinating Vigna mungo Seeds.

    PubMed

    Mitsuhashi, W; Koshiba, T; Minamikawa, T

    1986-03-01

    Two major endopeptidases were present in cotyledons of germinating Vigna mungo seeds, as detected by the zymogram after polyacrylamide gel electrophoresis. They were not detectable in cotyledons of dry seeds, but their intensities on the zymogram increased during germination. During incubation of detached cotyledons, however, the activities showed only a slight increase for 5 days. These two endopeptidases could be separated by Sephacryl S-200 column chromatography. One of them was found to be a serine-endopeptidase as judged by phenylmethylsulfonylfluoride and diisopropyl fluorophosphate inhibition. The other was a sulfhydryl-endopeptidase because of its dependency on 2-mercaptoethanol and inhibition by leupeptin, chymostatin, and antipain. Analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis indicatd that the two endopeptidases digested the Vigna mungo seed globulin subunits at different rates. The serine enzyme digested the 56 kilodalton subunit at first, but the sulfhydryl enzyme digested the 54 kilodalton peptide more efficiently than the 56 kilodalton peptide. The pattern of digestion of globulin by the combination of the serine- and sulfhydryl-endopeptidases was similar to that using crude enzyme extracts.

  12. 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.

  13. 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.

  14. 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.

  15. 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. PMID:25352428

  16. 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

  17. Separation between HIV-positive women and their children: the French prospective study, 1986 through 1993.

    PubMed Central

    Blanche, S; Mayaux, M J; Veber, F; Landreau, A; Courpotin, C; Vilmer, E; Ciraru-Vigneron, N; Flock, C; Tricoire, J; Noseda, G; Retbi, J M; Rouzioux, C

    1996-01-01

    OBJECTIVES. We studied the risk and circumstances of separation (due to either maternal death or drug use) between women infected by human immunodeficiency virus (HIV) type 1 and their children. METHODS. This analysis was based on the French Prospective Study of Infants Born to HIV-seropositive Women (1986 through 1993). Data recorded at each follow-up visit included the mother's effective presence with the child and the child's care after separation. RESULTS. A child's cumulative risk of long-term or permanent separation from his or her mother was 37% at 60 months. Maternal drug use was associated with an added risk during the child's first years (adjusted relative risk [RR]=3.4, 95% confidence interval [CI]=2.3, 5.0). The risk among drug users was even higher when the mother used injection drugs during pregnancy (adjusted RR=2.9, 95% CI=1.9, 4.3). Risk of early separation related to drug use tended to diminish since survey initiation. After separation, 57% of the children were placed through child welfare services and 43% were cared for by relatives. CONCLUSIONS. In the French Prospective Study, 2% to 3% of HIV-infected children were separated each year from their mothers as a result of the mothers death from acquired immunodeficiency syndrome (AIDS). Separations related to drug use have decreased over the years, and the family is becoming the most frequent carer after separation. PMID:8604763

  18. [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.

  19. 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.

  20. Preparation and characterization of a molecularly imprinted monolithic column for pressure-assisted CEC separation of nitroimidazole drugs.

    PubMed

    Liao, Sulan; Wang, Xiaochun; Lin, Xucong; Xie, Zenghong

    2010-08-01

    A polymethacrylate-based molecularly imprinted monolithic column bearing mixed functional monomers, using non-covalent imprinting approach, was designed for the rapid separation of nitroimidazole compounds. The new monolithic column has been prepared via simple in situ polymerization of 2-hydroxyethyl methacrylate, dimethylaminoethyl methacrylate and ethylene dimethacrylate, using (S)-ornidazole ((S)-ONZ) as template in a binary porogenic mixture consisting of toluene and dodecanol. The composition of the polymerization mixture was systematically altered and optimized by altering the amount of monomers as well as the composition of the porogenic solvent. The column performance was evaluated in pressure-assisted CEC mode. Separation conditions such as pH, voltage, amount of organic modifier and salt concentration were studied. The optimized monolithic column resulted in excellent separation of a group of structurally related nitroimidazole drugs within 10 min in isocratic elution condition. Column efficiencies of 99 000, 80 000, 103 000, 60 000 and 99 000 plates/m were obtained for metronidazole, secnidazole, ronidazole, tinidazole and dimetridazole, respectively. Parallel experiments were carried out using molecularly imprinted and non-imprinted capillary columns. The separation might be the result of combined effects including hydrophobic, hydrogen bonding and the imprinting cavities on the (S)-ONZ-imprinted monolithic column. PMID:20661943

  1. Separation and characterization of two chemically distinct lipopolysaccharides in two Pectinatus species.

    PubMed Central

    Helander, I M; Hurme, R; Haikara, A; Moran, A P

    1992-01-01

    Lipopolysaccharides (LPS) from the type strains of the anaerobic beer spoilage bacteria Pectinatus cerevisiiphilus and P. frisingensis were extracted with the 5:5:8 volume ratio modification of the phenolchloroform-petroleum ether method (H. Brade and C. Galanos, Eur. J. Biochem. 122:233-237, 1982). Sequential precipitations of LPS with water and acetone from the phenol phase yielded LPS which differed in that water-precipitable material (LPS-H2O; 0.1 to 0.4% of the dry weight of the cells) was rough-type LPS, whereas acetone-precipitable material (LPS-Ac; 4.6 to 5.8% of the dry weight) contained both rough-type LPS and high-molecular-weight material resembling smooth LPS. The LPS were chemically characterized, and they contained D-glucosamine, 4-amino-4-deoxy-L-arabinose, 3-deoxy-D-manno-2-octulosonic acid, D-fucose, D-galactose, D-glucose, D-mannose, and phosphate. D-Fucose was present mostly in LPS-Ac, suggesting that it is a constituent of the O antigen. The major fatty acids were ester- and amide-linked (R)-3-hydroxytridecanoic and ester-linked undecanoic acids, with minor amounts of ester-linked tridecanoic and (R)-3-hydroxyundecanoic acids. The chemical compositions of LPS-H2O and LPS-Ac suggested that they differ not only in their smooth or rough nature but also in the structure of their core regions. This may explain their different precipitabilities from the extraction mixture. The extraction method was also shown to be applicable to the isolation of smooth-type LPS from Salmonella enterica serovar Typhimurium. Extraction of two Typhimurium strains carrying chemically different O antigens resulted in high yields (8% of the dry weight) of LPS. Strain SH2183, which contains the relatively hydrophobic O-4,5,12 antigen yielded almost exclusively LPS-Ac, whereas the LPS of strain SH5770, which has a hydrophilic O-6,7 antigen, was exclusively LPS-H2O. No fractionation to smooth and rough LPS occurred with the Typhimurium strains. Images PMID:1577699

  2. An Experimental Study of Flow Separation over 2D Transverse Grooves

    NASA Astrophysics Data System (ADS)

    Jones, Emily; Lang, Amy; Afroz, Farhana; Wheelus, Jennifer; Smith, Drew

    2011-11-01

    A shark's scales help to reduce drag over its body by controlling boundary layer separation over its skin. It is theorized that the scales bristle when encountering a reversing flow, thereby trapping vortices between the scales, creating a partial slip condition over the surface and inducing turbulence augmentation in the boundary layer. In an attempt to replicate and study these effects, a spinning cylinder was used in a water tunnel to induce separation over a flat plate with 2 millimeter square 2D transverse grooves. The results were compared to separation occurring over a flat plate without grooves using DPIV. The angular speed of the cylinder was varied. The observed delays in separation, changes in separation bubble shedding frequency and other effects upon the boundary layer are discussed.

  3. 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.

  4. 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.

  5. Separation of important new platelet glycoproteins (GPIa, GPIc, GPIc*, GPIIa and GMP-140) by f.p.l.c. Characterization by monoclonal antibodies and gas-phase sequencing.

    PubMed

    Catimel, B; Parmentier, S; Leung, L L; McGregor, J L

    1991-10-15

    A large number of membrane glycoproteins (around 40) are present on the surface of human blood platelets. Some of these glycoproteins are expressed in relatively small amounts, and their functions, as well as their structure, remain to be elucidated. The aim of the present study was to separate rapidly, under non-denaturing conditions, and characterize minor glycoproteins such as Very Late Antigens (VLA) (GPIa, GPIc, GPIc* and GPIIa) and GMP-140 (also known as PADGEM). VLAs and GMP-140 are respectively members of the integrin and selectin families. Platelet membrane glycoproteins were separated by wheat-germ agglutinin lectin affinity and Mono Q anion-exchange f.p.l.c. Peaks bearing isolated glycoproteins were electrophoresed on one- or two-dimensional SDS/polyacrylamide gels, Western blotted on to Immobilon poly(vinylidene difluoride) membranes and gas-phase-sequenced. The identity of isolated glycoproteins was also obtained by the use of monoclonal or polyclonal antibodies and tryptic peptide maps. Five minor [GPIa, GPIc, GPIc*, GPIIa and GMP 140 (PADGEM)], as well as a major (GPIIIb) glycoprotein, were eluted at low salt concentrations. GPIIb-IIIa and GPIb were eluted at high salt concentrations. The N-terminal sequence of platelet GPIa was identical with that obtained by Takada & Hemler [(1989) J. Cell Biol. 109, 397-407]. However, the N-terminal sequence of platelet GPIc + Ic* and GPIIa were found to differ from those deduced from cDNA sequences isolated from human placenta or umbilical-vein endothelial-cell cDNA libraries. The combined use of f.p.l.c. and gas-phase sequencing techniques provides a very powerful tool to separate and characterize rapidly platelet or other cellular proteins for structural, immunological and functional studies.

  6. A novel microfluidic platform for size and deformability based separation and the subsequent molecular characterization of viable circulating tumor cells

    PubMed Central

    Parveen, Z.; Wagner, C.; Janning, M.; Quidde, J.; Stein, A.; Müller, V.; Loges, S.; Neves, R.P.L.; Stoecklein, N.H.; Wikman, H.; Riethdorf, S.; Pantel, K.; Gorges, T.M.

    2016-01-01

    Circulating tumor cells (CTCs) were introduced as biomarkers more than 10 years ago, but capture of viable CTCs at high purity from peripheral blood of cancer patients is still a major technical challenge. Here, we report a novel microfluidic platform designed for marker independent capture of CTCs. The Parsortix™ cell separation system provides size and deformability‐based enrichment with automated staining for cell identification, and subsequent recovery (harvesting) of cells from the device. Using the Parsortix™ system, average cell capture inside the device ranged between 42% and 70%. Subsequent harvest of cells from the device ranged between 54% and 69% of cells captured. Most importantly, 99% of the isolated tumor cells were viable after processing in spiking experiments as well as after harvesting from patient samples and still functional for downstream molecular analysis as demonstrated by mRNA characterization and array‐based comparative genomic hybridization. Analyzing clinical blood samples from metastatic (n = 20) and nonmetastatic (n = 6) cancer patients in parallel with CellSearch® system, we found that there was no statistically significant difference between the quantitative behavior of the two systems in this set of twenty six paired separations. In conclusion, the epitope independent Parsortix™ system enables the isolation of viable CTCs at a very high purity. Using this system, viable tumor cells are easily accessible and ready for molecular and functional analysis. The system's ability for enumeration and molecular characterization of EpCAM‐negative CTCs will help to broaden research into the mechanisms of cancer as well as facilitating the use of CTCs as “liquid biopsies.” PMID:26789903

  7. 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.

  8. 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.

  9. The use of acid alumina and Sephadex LH-20 for the separation and characterization of ethanol-soluble peptides produced by Bacillus brevis

    PubMed Central

    Bartley, I. M.; Hodgson, B.; Walker, J. S.; Holme, G.

    1972-01-01

    Cell extracts from Bacillus brevis (A.T.C.C. 10068), grown with various media, incorporated certain 14C-labelled amino acids that are normally components of tyrothricin into material that was extracted by ethanol from the precipitate formed by adding acid. When this material was separated by paper and silica-gel thin-layer chromatography and paper electrophoresis 14C was located in those regions that also contained gramicidin and tyrocidine. From a study of the properties of the system responsible for the incorporation it was deduced that non-tyrothricin materials were present. It was shown that the methods normally used to characterize tyrothricin do not adequately distinguish between tyrothricin and non-tyrothricin materials. However, a method for separating these materials was devised. This involved elution with ethanol from columns of acid alumina followed by gel filtration on Sephadex LH-20 with dimethylformamide–water solvent. The behaviour of gramicidin and tyrocidine on the Sephadex LH-20 column was examined, and it was concluded that the separation was not caused simply by gel filtration of unassociated molecules. Also, tyrocidine molecules with different amino acid compositions seemed to have different affinities for the Sephadex LH-20 column. PMID:5076191

  10. Chromatographic purification and characterization of B-phycoerythrin from Porphyridium cruentum. Semipreparative high-performance liquid chromatographic separation and characterization of its subunits.

    PubMed

    Bermejo, R; Talavera, E M; Alvarez-Pez, J M

    2001-05-11

    A fast preparative two-step chromatographic method for purification of B-phycoerythrin from Porphyridium cruentum is described. This biliprotein was homogeneous as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis yielding three closely migrating bands corresponding to its three subunits. Baseline separation of its alpha-, beta- and gamma-subunits was achieved by a reversed-phase HPLC gradient semipreparative method with a C4 large-pore column and a solvent system consisting of 0.05% trifluoroacetic acid (TFA) in water and 0.05% TFA in acetonitrile. B-Phycoerythrin in different aggregation states and its subunits have been spectroscopically characterized. Hexameric B-phycoerythrin has similar secondary and tertiary structure than dissociated B-phycoerythrin determined by circular dichroism.

  11. PRELIMINARY CHARACTERIZATION OF CO2 SEPARATION AND STORAGE PROPERTIES OF COAL GAS RESERVOIRS

    SciTech Connect

    John Kemeny; Satya Harpalani

    2004-03-01

    An attractive alternative of sequestering CO{sub 2} is to inject it into coalbed methane reservoirs, particularly since it has been shown to enhance the production of methane during near depletion stages. The basis for enhanced coalbed methane recovery and simultaneous sequestration of carbon dioxide in deep coals is the preferential sorption property of coal, with its affinity for carbon dioxide being significantly higher than that for methane. Yet, the sorption behavior of coal under competitive sorptive environment is not fully understood. Hence, the original objective of this research study was to carry out a laboratory study to investigate the effect of studying the sorption behavior of coal in the presence of multiple gases, primarily methane, CO{sub 2} and nitrogen, in order to understand the mechanisms involved in displacement of methane and its movement in coal. This had to be modified slightly since the PVT property of gas mixtures is still not well understood, and any laboratory work in the area of sorption of gases requires a definite equation of state to calculate the volumes of different gases in free and adsorbed forms. This research study started with establishing gas adsorption isotherms for pure methane and CO{sub 2}. The standard gas expansion technique based on volumetric analysis was used for the experimental work with the additional feature of incorporating a gas chromatograph for analysis of gas composition. The results were analyzed first using the Langmuir theory. As expected, the Langmuir analysis indicated that CO{sub 2} is more than three times as sorptive as methane. This was followed by carrying out a partial desorption isotherm for methane, and then injecting CO{sub 2} to displace methane. The results indicated that CO{sub 2} injection at low pressure displaced all of the sorbed methane, even when the total pressure continued to be high. However, the displacement appeared to be occurring due to a combination of the preferential

  12. 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.

  13. Stage separation study of Nike-Black Brant V Sounding Rocket System

    NASA Technical Reports Server (NTRS)

    Ferragut, N. J.

    1976-01-01

    A new Sounding Rocket System has been developed. It consists of a Nike Booster and a Black Brant V Sustainer with slanted fins which extend beyond its nozzle exit plane. A cursory look was taken at different factors which must be considered when studying a passive separation system. That is, one separation system without mechanical constraints in the axial direction and which will allow separation due to drag differential accelerations between the Booster and the Sustainer. The equations of motion were derived for rigid body motions and exact solutions were obtained. The analysis developed could be applied to any other staging problem of a Sounding Rocket System.

  14. Biomimetic Precapillary Flow Patterns for Enhancing Blood Plasma Separation: A Preliminary Study

    PubMed Central

    Namgung, Bumseok; Tan, Justin Kok Soon; Wong, Peter Agustinus; Park, Sung-Yong; Leo, Hwa Liang; Kim, Sangho

    2016-01-01

    In this study, a biomimetic microfluidic plasma separation device is discussed. The design of the device drew inspiration from in vivo observations of enhanced cell-free layer (CFL) formation downstream of vascular bifurcations. The working principle for the plasma separation was based on the plasma skimming effect in an arteriolar bifurcation, which is modulated by CFL formation. The enhancement of the CFL width was achieved by a local hematocrit reduction near the collection channel by creating an uneven hematocrit distribution at the bifurcation of the channel. The device demonstrated a high purity of separation (~99.9%) at physiological levels of hematocrit (~40%). PMID:27657090

  15. Studies of flow separation and stalling on one- and two-element airfoils at low speeds

    NASA Technical Reports Server (NTRS)

    Seetharam, H. C.; Wentz, W. H., Jr.

    1977-01-01

    Research has been conducted on the nature of airfoil behavior at pre- and post-separated angles of attack. Detailed wind tunnel studies have been made of boundary layer and wake fields for the GA(W)-1 airfoil, and the airfoil with a 0.3 chord Fowler flap. Experimental data are compared with theoretical predictions from a multi-element viscous flow computer program. Theoretical predictions are reasonably accurate for unseparated flows, but have serious errors when separation is present. Some recent techniques for modeling post-separated flow behavior are discussed in light of the present experiments.

  16. 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.

  17. Identification and functional characterization of AclB, a novel cell-separating enzyme from Lactobacillus casei.

    PubMed

    Xu, Yi; Wang, Ting; Kong, Jian; Wang, Hui-Li

    2015-06-16

    Autolysis of nonstarter lactic acid bacteria (NSLAB) was favorable for the development of flavor compounds during cheese manufacture. Among these bacteria, Lb. casei was regarded as the most important microbiota involved in cheese processes. In this study, a novel autolysin named AclB was identified in the genome of Lb. casei BL23 and its modular structure was predicted through bioinformatic approaches. Subsequently, its transcription profile in the exponential phase, hydrolytic activities against cell walls, enzymatic properties under different conditions, physiological function via gene inactivation and upregulation assays, as well as potential applications to NSLAB's autolysis were fully investigated. According to the results, AclB was recognized as a species-specific cell-separating enzyme, responsible for cell separation after cell division in Lb. casei BL23. The purified AclB showed considerable hydrolyzing activities towards cell walls, indicating its enzymatic nature as peptidoglycan hydrolase, or autolysin. The highest activity of AclB was determined at pH5.0 and 37°C, and the expression vector constructed based on AclB was shown to facilitate the controlled lysis of Lb. casei BL23 hosts. In summary, this study provided insight into the enzymatic properties of a novel autolysin involved in cell separation of Lb. casei BL23, which is promising to accelerate cheese ripening and improve cheese quality. PMID:25797034

  18. Synthesis and characterization of magnetic hexacyanoferrate (II) polymeric nanocomposite for separation of cesium from radioactive waste solutions.

    PubMed

    Sheha, Reda R

    2012-12-15

    Nanocrystalline potassium zinc hexacyanoferrate loaded on nanoscale magnetite substrate was successfully synthesized for significantly enhanced removal of cesium from low-level radioactive wastes. A description was given for preparation and properties of these precursors. The physicochemical properties of these nanocomposites were determined using different techniques including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Data clarified that supporting potassium zinc hexacyanoferrates on iron ferrite nanoparticles increased their thermal stability. Further, Fourier transform infrared spectra confirmed that the nanocomposites were well coordinated and incorporated in the polymer matrix. The average particle sizes, of these nanoparticles, determined by SEM had a good agreement with XRD results. Based on characterization data, the prepared zinc hexacyanoferrates were proposed to have a zeolitic rhombohedral structure with cavities can host alkali metal ions and water molecules. The magnetic analysis showed a super-paramagnetic behavior. Batch technique was applied to evaluate the influences of initial pH value, contact time, and competing cations on the efficiency of cesium removal. The sorption process was fast initially, and maximum separation was attained within 2h of contact. Cesium exchange was independent from pH value and deviate from ideal exchange phenomena. In neutral solutions, Cs(+) was retained through exchange with K(+); however, in acidic solution, phase transformation was proposed. Sorption capacity of these materials attained values amounted 1965 mg g(-1). The synthesized nanocomposites exhibited different affinities toward Cs(I), Co(II), and Eu(III) elements and showed a good ability to separate them from each other.

  19. Parametric study of separation and transition characteristics over an airfoil at low Reynolds numbers

    NASA Astrophysics Data System (ADS)

    Boutilier, Michael S. H.; Yarusevych, Serhiy

    2012-06-01

    Time-resolved surface pressure measurements are used to experimentally investigate characteristics of separation and transition over a NACA 0018 airfoil for the relatively wide range of chord Reynolds numbers from 50,000 to 250,000 and angles of attack from 0° to 21°. The results provide a comprehensive data set of characteristic parameters for separated shear layer development and reveal important dependencies of these quantities on flow conditions. Mean surface pressure measurements are used to explore the variation in separation bubble position, edge velocity in the separated shear layer, and lift coefficients with angle of attack and Reynolds number. Consistent with previous studies, the separation bubble is found to move upstream and decrease in length as the Reynolds number and angle of attack increase. Above a certain angle of attack, the proximity of the separation bubble to the location of the suction peak results in a reduced lift slope compared to that observed at lower angles. Simultaneous measurements of the time-varying component of surface pressure at various spatial locations on the model are used to estimate the frequency of shear layer instability, maximum root-mean-square (RMS) surface pressure, spatial amplification rates of RMS surface pressure, and convection speeds of the pressure fluctuations in the separation bubble. A power-law correlation between the shear layer instability frequency and Reynolds number is shown to provide an order of magnitude estimate of the central frequency of disturbance amplification for various airfoil geometries at low Reynolds numbers. Maximum RMS surface pressures are found to agree with values measured in separation bubbles over geometries other than airfoils, when normalized by the dynamic pressure based on edge velocity. Spatial amplification rates in the separation bubble increase with both Reynolds number and angle of attack, causing the accompanying decrease in separation bubble length. Values of the

  20. 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

  1. A computer simulation study of the separation of aqueous solutions using thin zeolite membranes

    NASA Astrophysics Data System (ADS)

    Lin, J.; Murad, S.

    2001-07-01

    A recently developed molecular simulation scheme for studying solutions undergoing osmosis and reverse osmosis was used to study the separation of aqueous solutions using thin zeolite membranes. This method allows for the preservation of the atomic roughness of the membranes, while the molecules that constitute the membranes are also allowed to vibrate. In the simulations, two thin membranes cut from a cubic cell of ZK-4 zeolite were used as the semi-permeable membranes to separate water from aqueous NaCl solutions. Both osmosis and reverse-osmosis phenomena were observed. The study showed that ZK-4 zeolite membranes show promise for use in membrane-based separation of aqueous electrolyte solutions, as well as other similar systems.

  2. 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.

  3. Phase separation of fluids in porous media: A molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Ahmad, Shaista; Puri, Sanjay; Das, Subir K.

    2014-10-01

    We present comprehensive molecular dynamics results for phase-separation kinetics of fluids in a porous medium. This system is modeled by a symmetric Lennard-Jones fluid mixture with a quenched random field. The presence of disorder slows down domain growth from power-law to a logarithmic form. It also modifies the correlation functions and structure factors which characterize the morphology. In particular, the structure-factor tail shows a non-Porod behavior, which is the consequence of scattering from rough interfaces.

  4. Architecture Study on Telemetry Coverage for Immediate Post-Separation Phase

    NASA Technical Reports Server (NTRS)

    Cheung, Kar-Ming; Lee, Charles H.; Kellogg, Kent H.; Stocklin, Frank J.; Zillig, David J.; Fielhauer, Karl B.

    2008-01-01

    This paper presents the preliminary results of an architecture study that provides continuous telemetry coverage for NASA missions for immediate post-separation phase. This study is a collaboration effort between Jet Propulsion Laboratory (JPL), Goddard Space Flight Center (GSFC), and Applied Physics Laboratory (APL). After launch when the spacecraft separated from the upper stage, the spacecraft typically executes a number of mission-critical operations prior to the deployment of solar panels and the activation of the primary communication subsystem. JPL, GSFC, and APL have similar design principle statements that require continuous coverage of mission-critical telemetry during the immediate post-separation phase. To conform to these design principles, an architecture that consists of a separate spacecraft transmitter and a robust communication network capable of tracking the spacecraft signals is needed.This paper presents the preliminary results of an architecture study that provides continuous telemetry coverage for NASA missions for immediate post-separation phase. This study is a collaboration effort between Jet Propulsion Laboratory (JPL), Goddard Space Flight Center (GSFC), and Applied Physics Laboratory (APL). After launch when the spacecraft separated from the upper stage, the spacecraft typically executes a number of mission-critical operations prior to the deployment of solar panels and the activation of the primary communication subsystem. JPL, GSFC, and APL have similar design principle statements that require continuous coverage of mission-critical telemetry during the immediate post-separation phase. To conform to these design principles, an architecture that consists of a separate spacecraft transmitter and a robust communication network capable of tracking the spacecraft signals is needed. The main results of this study are as follows: 1) At low altitude (< 10000 km) when most post-separation critical operations are executed, Earth-based network

  5. 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

    2015-08-01

    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.

  6. 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.

  7. São Paulo aerosol characterization study.

    PubMed

    Alonso, C D; Martins, M H; Romano, J; Godinho, R

    1997-12-01

    The São Paulo Metropolitan area (SPMA) is characterized as having one of the worst air pollution problems in Brazil, with frequent violations of air quality standards for particulate matter. This paper presents the results of a receptor model source apportionment study carried out to develop a quantitative database on which a control strategy could be developed. The study was conducted in four sites with distinct land uses. Fine, coarse (CP), and total suspended particles (TSP) samples were collected on Teflon and glass filters and analyzed by x-ray fluorescence (XRF), ion chromatography, and thermal evolution. The sources were characterized by similar methodology. Chemical mass balance (CMB) receptor modeling indicated that carbonaceous material plays an important role in the aerosol composition; that the three major source categories contributing to the fine particles are vehicles, secondary carbon, and sulfates; and that the main contributors to CP and TSP are road dust and vehicles. All sampling sites presented the same general pattern in terms of source contribution, although this contribution varied from site to site.

  8. Field study of hydrogeologic characterization methods in a heterogeneous aquifer.

    PubMed

    Alexander, Matthew; Berg, Steven J; Illman, Walter A

    2011-01-01

    Hydraulic conductivity (K) and specific storage (S(s)) are required parameters when designing transient groundwater flow models. The purpose of this study was to evaluate the ability of commonly used hydrogeologic characterization approaches to accurately delineate the distribution of hydraulic properties in a highly heterogeneous glaciofluvial deposit. The metric used to compare the various approaches was the prediction of drawdown responses from three separate pumping tests. The study was conducted at a field site, where a 15 m × 15 m area was instrumented with four 18-m deep Continuous Multichannel Tubing (CMT) wells. Each CMT well contained seven 17 cm × 1.9 cm monitoring ports equally spaced every 2 m down each CMT system. An 18-m deep pumping well with eight separate 1-m long screens spaced every 2 m was also placed in the center of the square pattern. In each of these boreholes, cores were collected and characterized using the Unified Soil Classification System, grain size analysis, and permeameter tests. To date, 471 K estimates have been obtained through permeameter analyses and 270 K estimates from empirical relationships. Geostatistical analysis of the small-scale K data yielded strongly heterogeneous K fields in three-dimensions. Additional K estimates were obtained through slug tests in 28 ports of the four CMT wells. Several pumping tests were conducted using the multiscreen and CMT wells to obtain larger scale estimates of both K and S(s). The various K and S(s) estimates were then quantitatively evaluated by simulating transient drawdown data from three pumping tests using a 3D forward numerical model constructed using HydroGeoSphere (Therrien et al. 2005). Results showed that, while drawdown predictions generally improved as more complexity was introduced into the model, the ability to make accurate drawdown predictions at all CMT ports was inconsistent.

  9. 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

  10. Architecture Study on Telemetry Coverage for Immediate Post-Separation Phase

    NASA Technical Reports Server (NTRS)

    Cheung, Kar-Ming; Lee, Charles; Kellogg, Kent; Stocklin, Frank; Zillig, David; Fielhauer, Karl

    2008-01-01

    This document is the viewgraphs that accompanies a paper that presents the preliminary results of an architecture study that provides continuous telemetry coverage for NASA missions for immediate post-separation phase. After launch when the spacecraft separated from the upper stage, the spacecraft typically executes a number of mission-critical operations prior to the deployment of solar panels and the activation of the primary communication subsystem. JPL, GSFC, and APL have similar design principle statements that require continuous coverage of mission-critical telemetry during the immediate post-separation phase. To conform to these design principles, an architecture that consists of a separate spacecraft transmitter and a robust communication network capable of tracking the spacecraft signals is needed. The main results of this study are as follows: 1) At low altitude (< 10000 km) when most post-separation critical operations are executed, Earth-based network (e.g. Deep Space Network (DSN)) can only provide limited coverage, whereas space-based network (e.g. Space Network (SN)) can provide continuous coverage. 2) Commercial-off-the-shelf SN compatible transmitters are available for small satellite applications. In this paper we present the detailed coverage analysis of Earth-based and Space-based networks. We identify the key functional and performance requirements of the architecture, and describe the proposed selection criteria of the spacecraft transmitter. We conclude the paper with a proposed forward plan.

  11. 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.

  12. Acetylcholinesterase from Apis mellifera head. Evidence for amphiphilic and hydrophilic forms characterized by Triton X-114 phase separation.

    PubMed

    Belzunces, L P; Toutant, J P; Bounias, M

    1988-10-15

    The polymorphism of bee acetylcholinesterase was studied by sucrose-gradient-sedimentation analysis and non-denaturing electrophoretic analysis of fresh extracts. Lubrol-containing extracts exhibited only one form, which sedimented at 5 S when analysed on high-salt Lubrol-containing gradients and 6 S when analysed on low-salt Lubrol-containing gradients. The 5 S/6 S form aggregated upon removal of the detergent when sedimented on detergent-free gradients and was recovered in the detergent phase after Triton X-114 phase separation. Thus the 5 S/6 S enzyme corresponds to an amphiphilic acetylcholinesterase form. In detergent-free extracts three forms, whose apparent sedimentation coefficients are 14 S, 11 S and 7 S, were observed when sedimentations were performed on detergent-free gradients. Sedimentation analyses on detergent-containing gradients showed only a 5 S peak in high-salt detergent-free extracts and a 6 S peak, with a shoulder at about 7 S, in low-salt detergent-free extracts. Electrophoretic analysis in the presence of detergent demonstrated that the 14 S and 11 S peaks corresponded to aggregates of the 5 S/6 S form, whereas the 7 S peak corresponded to a hydrophilic acetylcholinesterase form which was recovered in the aqueous phase following Triton X-114 phase separation. The 5 S/6 S amphiphilic form could be converted into a 7.1 S hydrophilic form by phosphatidylinositol-specific phospholipase C digestion.

  13. Acetylcholinesterase from Apis mellifera head. Evidence for amphiphilic and hydrophilic forms characterized by Triton X-114 phase separation.

    PubMed Central

    Belzunces, L P; Toutant, J P; Bounias, M

    1988-01-01

    The polymorphism of bee acetylcholinesterase was studied by sucrose-gradient-sedimentation analysis and non-denaturing electrophoretic analysis of fresh extracts. Lubrol-containing extracts exhibited only one form, which sedimented at 5 S when analysed on high-salt Lubrol-containing gradients and 6 S when analysed on low-salt Lubrol-containing gradients. The 5 S/6 S form aggregated upon removal of the detergent when sedimented on detergent-free gradients and was recovered in the detergent phase after Triton X-114 phase separation. Thus the 5 S/6 S enzyme corresponds to an amphiphilic acetylcholinesterase form. In detergent-free extracts three forms, whose apparent sedimentation coefficients are 14 S, 11 S and 7 S, were observed when sedimentations were performed on detergent-free gradients. Sedimentation analyses on detergent-containing gradients showed only a 5 S peak in high-salt detergent-free extracts and a 6 S peak, with a shoulder at about 7 S, in low-salt detergent-free extracts. Electrophoretic analysis in the presence of detergent demonstrated that the 14 S and 11 S peaks corresponded to aggregates of the 5 S/6 S form, whereas the 7 S peak corresponded to a hydrophilic acetylcholinesterase form which was recovered in the aqueous phase following Triton X-114 phase separation. The 5 S/6 S amphiphilic form could be converted into a 7.1 S hydrophilic form by phosphatidylinositol-specific phospholipase C digestion. Images Fig. 3. Fig. 6. PMID:2849414

  14. A soap technique for cell separation to study the seed coat of Sesbania punicea.

    PubMed

    Bevilacqua, L; Massa, G; Modenesi, P; Fossati, F

    1993-05-01

    A technique is described for separating plant cells used for morphological studies. The plant material is placed in a concentrated solution of olive oil castile soap for 1-2 days or more. The material is then thoroughly washed and placed between two glass slides. The upper glass slide is lifted from the lower one, then gently pressed down several times. Through this procedure Malpighian cells of the seed coat of Sesbania punicea, mesophyll cells of Euphorbia peplus and of Trifolium pratense and cortical cells of the aerial roots of Monstera deliciosa have been separated. Various shapes of the Malpighian cells of the Sesbania punicea seed coat can be observed along with intermediates.

  15. A qualitative study of incarcerated mothers' perceptions of the impact of separation on their children.

    PubMed

    Gilham, Jerry Jo M

    2012-01-01

    Many incarcerated women are mothers, and their children exhibit various responses to the separation that incarceration commands. This exploratory qualitative study examines incarcerated women's perceptions of the consequences of their illegal activity, confinement, and separation from their children on their offspring. The results indicate that although mothers are concerned about their children, they are typically unable to recognize the negative consequences of their actions on their children and their relationship with their children until beginning intensive treatment. Effective treatment must focus on the woman's personal issues along with their parenting abilities and skills to repair these relationships and promote healthy family functioning. PMID:22239380

  16. Numerical study of a separating and reattaching flow by using Reynolds-stress tubulence closure

    NASA Technical Reports Server (NTRS)

    Amano, R. S.; Goel, P.

    1983-01-01

    The numerical study of the Reynolds-stress turbulence closure for separating, reattaching, recirculating and redeveloping flow is summarized. The calculations were made for two different closure models of pressure - strain correlation. The results were compared with the experimental data. Furthermore, these results were compared with the computations made by using the one layer and three layer treatment of k-epsilon turbulence model which were developed. Generally the computations by the Reynolds-stress model show better results than those by the k-epsilon model, in particular, some improvement was noticed in the redeveloping region of the separating and reattaching flow in a pipe with sudden expansion.

  17. A numerical study of a separating and reattaching flow by using Reynolds-stress turbulence closure

    NASA Technical Reports Server (NTRS)

    Amano, R. S.; Goel, P.

    1984-01-01

    The numerical study of the Reynolds-stress turbulence closure for separating, reattaching, recirculating and redeveloping flow is summarized. The calculations were made for two different closure models of pressure-strain correlation. The results were compared with the experimental data. Furthermore, these results were compared with the computations made by using the one layer and three layer treatment of k-epsilon turbulence model which were developed. Generally the computations by the Reynolds-stress model show better results than those by the k-epsilon model, in particular, some improvement was noticed in the redeveloping region of the separating and reattaching flow in a pipe with sudden expansion.

  18. 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.

  19. Separation-Individuation Conflict as a Model for Understanding Distressed Caregivers: Psychodynamic and Cognitive Case Studies.

    ERIC Educational Resources Information Center

    Rose, Jonathon M.; DelMaestro, Susan G.

    1990-01-01

    Discusses Project Assist, a project designed to study efficacy of time-limited psychodynamic and cognitive behavioral therapies for experienced and recent caregivers. Claims Project Assist offers psychotherapy that can assist caregivers in separating their own emotions, identity, and well-being from those of care receiver, a process which appears…

  20. 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…

  1. 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.

  2. 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...

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

    PubMed

    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

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

    NASA Astrophysics Data System (ADS)

    Sun, Zongli; Gu, Qiang

    2016-08-01

    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.

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. Adsorptive separation of ethylene/ethane mixtures using carbon nanotubes: a molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Tian, Xingling; Wang, Zhigang; Yang, Zaixing; Xiu, Peng; Zhou, Bo

    2013-10-01

    Ethylene/ethane separation is a very important process in the chemical industry. Traditionally, this process is achieved by cryodistillation, which is extremely energy-intensive. The adsorptive separation is an energy-saving and environmentally benign alternative. In this study, we employ molecular dynamics simulations to study the competitive adsorption of an equimolar mixture of gaseous ethane and ethylene inside single-walled carbon nanotubes (SWNTs) of different diameters at room temperature. We find that for narrow SWNTs, i.e. the (6, 6) and (7, 7) SWNTs, the selectivities towards ethane, fselec, can reach values of 3.1 and 3.7, respectively. Such high selectivities are contrary to the opinion of many researchers that the adsorptive separation of an ethylene/ethane mixture by means of dispersion interaction is difficult due to the same carbon number of ethane and ethylene. The key for our observation is that the role of dispersion interaction of ethane's additional two hydrogen atoms with the SWNT becomes significant under extreme confinement. Interestingly, the (8, 8) SWNT prefers ethylene to ethane with fselec = 0.6. For wider SWNTs, fselec converges to ∼1. The mechanisms behind these observations, as well as the kinetics of single-file nanopore filling and kinetics of confined gas molecules are discussed. Our findings suggest that efficient ethane/ethylene separation can be achieved by using bundles/membranes of SWNTs with appropriate diameters.

  17. Preparation and characterization of a PVDF-HFP/PEGDMA-coated PE separator for lithium-ion polymer battery by electron beam irradiation

    NASA Astrophysics Data System (ADS)

    Sohn, Joon-Yong; Im, Jong Su; Gwon, Sung-Jin; Choi, Jae-Hak; Shin, Junhwa; Nho, Young-Chang

    2009-07-01

    In this study, polyethylene separators were modified by dip coating of polyethylene (PE) separators in poly(vinylidene fluoride- co-hexafluoropropylene)/poly(ethylene glycol) dimethacrylate (PVDF-HFP/PEGDMA) mixtures at different humidity levels (0-50%), followed by electron beam irradiation. Micro-porous structures of the coating layer were generated by performing dip-coating process at high humidity levels (i.e. phase inversion process) and were found to be affected by the PEGDMA content and humidity level. The thermal shrinkage of the prepared separators significantly decreased with increasing EB absorption dose due to the formation of crosslinked networks of the PVDF-HFP/PEGDMA-coated PE separators. It was also observed that the separators prepared under high humidity condition showed a higher liquid electrolyte uptake and the ionic conductivity than the original PE separators.

  18. 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

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

    PubMed

    Chai, Yunzhou; Kochetkov, Alexander; Reible, Danny D

    2007-07-01

    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 degrees 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 degrees 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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

    2015-01-01

    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. PMID:25541091

  9. 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

    2015-01-01

    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.

  10. Characterization of diesel fuel by chemical separation combined with capillary gas chromatography (GC) isotope ratio mass spectrometry (IRMS).

    PubMed

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

    2012-09-15

    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 diesel samples from different sources/locations. The ability to differentiate or correlate diesel samples could be valuable for discovering fuel tax evasion schemes or for environmental forensic studies. Two urea adduction-based techniques were used to isolate the n-alkanes from the fuel. Both carbon isotope ratio (δ(13)C) and hydrogen isotope ratio (δD) values for the n-alkanes were then determined by CSIA in each sample. The samples investigated had δ(13)C values that ranged from -30.1‰ to -26.8‰, whereas δD values ranged from -83‰ to -156‰. Plots of δD versus δ(13)C 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 δ(13)C, δD, or combined δ(13)C and δD data was applied to extract the maximum information content. PCA scores plots could clearly differentiate the samples, thereby demonstrating the potential of this approach for distinguishing (e.g., fingerprinting) fuel samples using δ(13)C and δD values.

  11. Characterization of the physical parameters in a process of magnetic separation and pressure-driven flow of a magnetic fluid

    NASA Astrophysics Data System (ADS)

    Cunha, F. R.; Sobral, Y. D.

    2004-11-01

    The equations governing the motion of a magnetic fluid are presented. These equations are non-linear and give rise to non-Newtonian effects attributable to the magnetization of the fluid. The equations are made dimensionless and the physical parameters of the coupled hydrodynamic-magnetic problem identified. The study is first applied to describe the motion of a magnetic droplet freely suspended in a viscous fluid undergoing a permanent magnetic field. A first-order theory is developed for the regime of small drop deformation in which viscous forces dominate inertial hydrodynamic force. At this regime, it is shown that the drift velocity of a magnetic drop scales with the square of the applied magnetic field and the deformation of the drop scales linearly with the applied field. Experiments are carried out and the range of validity of the small deformation analysis determined. The pressure-driven flow of a magnetic fluid is solved by a regular asymptotic expansion for two cases: a Poiseuille flow of a single magnetic fluid and a core pipe flow with a magnetic fluid adjacent to the tube wall. The theory is used to predict the volume rate of a viscous magnetic fluid separated from a non-magnetic viscous fluid by the action of a magnetic field. The apparent viscosity of a magnetic fluid as a function of magnetic parameters is also examined from our theory. A possible application of the present theoretical studies is on the remediation technology addressed to oil spills in natural environments.

  12. Characterization of diesel fuel by chemical separation combined with capillary gas chromatography (GC) isotope ratio mass spectrometry (IRMS).

    PubMed

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

    2012-09-15

    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 diesel samples from different sources/locations. The ability to differentiate or correlate diesel samples could be valuable for discovering fuel tax evasion schemes or for environmental forensic studies. Two urea adduction-based techniques were used to isolate the n-alkanes from the fuel. Both carbon isotope ratio (δ(13)C) and hydrogen isotope ratio (δD) values for the n-alkanes were then determined by CSIA in each sample. The samples investigated had δ(13)C values that ranged from -30.1‰ to -26.8‰, whereas δD values ranged from -83‰ to -156‰. Plots of δD versus δ(13)C 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 δ(13)C, δD, or combined δ(13)C and δD data was applied to extract the maximum information content. PCA scores plots could clearly differentiate the samples, thereby demonstrating the potential of this approach for distinguishing (e.g., fingerprinting) fuel samples using δ(13)C and δD values. PMID:22967550

  13. 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

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    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, La5/8-yPryCa3/8MnO3 (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.

  15. 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.

  16. 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.

  17. 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

    2012-12-01

    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. PMID:23050265

  18. TANK 4 CHARACTERIZATION, SETTLING, AND WASHING STUDIES

    SciTech Connect

    Bannochie, C.; Pareizs, J.; Click, D.; Zamecnik, J.

    2009-09-29

    A sample of PUREX sludge from Tank 4 was characterized, and subsequently combined with a Tank 51 sample (Tank 51-E1) received following Al dissolution, but prior to a supernate decant by the Tank Farm, to perform a settling and washing study to support Sludge Batch 6 preparation. The sludge source for the majority of the Tank 51-E1 sample is Tank 12 HM sludge. The Tank 51-E1 sample was decanted by SRNL prior to use in the settling and washing study. The Tank 4 sample was analyzed for chemical composition including noble metals. The characterization of the Tank 51-E1 sample, used here in combination with the Tank 4 sample, was reported previously. SRNL analyses on Tank 4 were requested by Liquid Waste Engineering (LWE) via Technical Task Request (TTR) HLE-TTR-2009-103. The sample preparation work is governed by Task Technical and Quality Assurance Plan (TTQAP), and analyses were controlled by an Analytical Study Plan and modifications received via customer communications. Additional scope included a request for a settling study of decanted Tank 51-E1 and a blend of decanted Tank 51-E1 and Tank 4, as well as a washing study to look into the fate of undissolved sulfur observed during the Tank 4 characterization. The chemistry of the Tank 4 sample was modeled with OLI Systems, Inc. StreamAnalyzer to determine the likelihood that sulfate could exist in this sample as insoluble Burkeite (2Na{sub 2}SO{sub 4} {center_dot} Na{sub 2}CO{sub 3}). The OLI model was also used to predict the composition of the blended tank materials for the washing study. The following conclusions were drawn from the Tank 4 analytical results reported here: (1) Any projected blend of Tank 4 and the current Tank 51 contents will produce a SB6 composition that is lower in Ca and U than the current SB5 composition being processed by DWPF. (2) Unwashed Tank 4 has a relatively large initial S concentration of 3.68 wt% on a total solids basis, and approximately 10% of the total S is present as an

  19. 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.

  20. Parametric study of complex distillation flowsheets for the separations of five-component mixtures

    SciTech Connect

    Rong, B.G.; Zheng, S.Q.; Zhou, C.G.

    1996-12-31

    Twenty two distillation flowsheets are studied for the separations of five-component mixtures based on the energy consumption and the annual costs. Fourteen flowsheets with simple columns and eight flowsheets with complex columns of side strippers and/or side rectifiers are included. Several five-component mixtures are selected, for various cases of feed composition distribution, the costs of the flowsheets are calculated and compared. Several heuristics are produced for the synthesis of distillation flowsheets with complex columns.

  1. 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.

  2. 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

  3. 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)

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. Study of the Pressure Rise Across Shock Waves Required to Separate Laminar and Turbulent Boundary Layers

    NASA Technical Reports Server (NTRS)

    Donaldson, Coleman Dup; Lange, Roy H

    1952-01-01

    Results are presented of a dimensional study and an experimental investigation of the pressure rise across a shock wave which causes separation of the boundary layer on a flat plate. The experimental part of the investigation was conducted at a Mach number of 3.03 for a Reynolds number range of 2 x 10 (sup) 6 to 19 x 10 (sup) 6. The available experimental data are compared with the predictions of the present study, and the significance of the results obtained is discussed relative to certain practical design problems.

  9. 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.

  10. 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.

  11. Studies of the separation performance of silanized silica gel for simulated distillation.

    PubMed

    Boczkaj, Grzegorz; Momotko, Malwina; Przyjazny, Andrzej; Kamiński, Marian

    2016-02-01

    We present the results of investigations of the chromatographic (sorptive) properties of silanized silica gel as a stationary phase for gas chromatography used for simulated distillation. Commercially available silanized sorbent (particle diameter range 63-200 μm, average pore size 60 Å) was sieved to obtain the 80-100 mesh fraction (180-150 μm). The obtained results revealed that silanized silica gel allows the complete separation of a mixture of n- and iso-alkanes in the C1 -C7 range. Such a separation is achieved with a temperature program starting with an initial temperature of 50˚C, which is advantageous because the gas chromatograph oven does not have to be cooled below room temperature. The use of temperature programming with a final temperature of 300˚C ensures separation and elution of all mixture components from C1 to n-C28 in one run. This study confirms the applicability of silanized silica gel as a stationary phase for the investigation of distillation temperature distribution of gasoline and diesel fuel based on the simulated distillation procedure according to ASTM D2887. The deviations of individual points of distillation curve obtained using ASTM D2887 and columns packed with silanized silica gel were within the reproducibility range of the standard procedure. PMID:26634792

  12. Basic Study on Hydrogen Separation and Compression Characteristics by Polymer Electrolyte Membrane

    NASA Astrophysics Data System (ADS)

    Ikeda, Takanobu; Ichihara, Keiji; Sunakawa, Daisuke; Hattori, Kikuo; Araki, Takuto; Onda, Kazuo; Igarashi, Motohisa; Motoyoshi, Tomoyuki

    Fuel cells (FC) can hardly react a hundred percent of fuel, because the cell potential becomes zero if all of the fuel is consumed at FC. Therefore a small amount of fuel is released from FC, even when pure H2 gas is used as fuel. If the space, where the exhaust H2 is released, is closed up such as the space of deep underground or undersea, the released amount of H2 may be restricted to an allowable level. The depleted H2 can be recovered by the hydrogen separation pump (HSP) such as proposed here. When we supply electricity to the polymer electrolyte by an external power source, H2 can easily be separated and pumped up from anode to cathode according to the principle of “concentration cell". In this study we have preliminarily tested the HSP, and our experimental results show that the HSP can work as a good separation and compression pump of exhausted hydrogen from FC. The typical cell potential was 100mV for HSP at our experimental condition of current density of 0.49A/cm2 and H2 treatment ratio of 98%.

  13. Comparison study of solid-liquid separation techniques for oilfield pit closures

    SciTech Connect

    Wojtanowicz, A.C.; Field, S.D.; Osterman, M.C.

    1986-01-01

    Extensive bench-scale and full-scale experiments were conducted at the LSU Solids Control Environmental Laboratory in order to evaluate application of the solids-liquid separation technology to oilfield waste pit volume reduction. The experiments addressed chemical conditioning of various pit slurries such as water-base and oil-base mud reserve pit slurries, mixed sludge from offshore operations, and oil production pit slurry. Effective treatment was found for the majority of the waste samples with pH adjustment and with nonionic and low-charge anionic, high molecular weight polymers. Ultimate dewaterability of various samples was determined by use of the belt press bench simulator. Bench simulators of belt press filtration, vacuum filtration and centrifuge sedimentation were used for design and optimization of the full-scale tests. Alternative solid-liquid separation techniques such as vacuum filtration, belt press filtration, screw press filtration and centrifuging were pilot-tested using field-size equipment and 200 bbls samples of water-base mud, reserve pit slurry and production pit sludge. The test data were analyzed at various operating conditions using a new graphical technique. Also, four typical oilfield solid-bowl centrifuges and a modern solid-bowl dewatering decanter were compared in a series of full-scale tests. Finally a preliminary process study on the mechanism of centrifuge separation of flocculated sludges was performed.

  14. Studies of the separation performance of silanized silica gel for simulated distillation.

    PubMed

    Boczkaj, Grzegorz; Momotko, Malwina; Przyjazny, Andrzej; Kamiński, Marian

    2016-02-01

    We present the results of investigations of the chromatographic (sorptive) properties of silanized silica gel as a stationary phase for gas chromatography used for simulated distillation. Commercially available silanized sorbent (particle diameter range 63-200 μm, average pore size 60 Å) was sieved to obtain the 80-100 mesh fraction (180-150 μm). The obtained results revealed that silanized silica gel allows the complete separation of a mixture of n- and iso-alkanes in the C1 -C7 range. Such a separation is achieved with a temperature program starting with an initial temperature of 50˚C, which is advantageous because the gas chromatograph oven does not have to be cooled below room temperature. The use of temperature programming with a final temperature of 300˚C ensures separation and elution of all mixture components from C1 to n-C28 in one run. This study confirms the applicability of silanized silica gel as a stationary phase for the investigation of distillation temperature distribution of gasoline and diesel fuel based on the simulated distillation procedure according to ASTM D2887. The deviations of individual points of distillation curve obtained using ASTM D2887 and columns packed with silanized silica gel were within the reproducibility range of the standard procedure.

  15. Are Attitudes Toward Writing and Reading Separable Constructs? A Study With Primary Grade Children.

    PubMed

    Graham, Steve; Berninger, Virginia; Abbott, Robert

    2012-01-01

    This study examined whether or not attitude towards writing is a unique and separable construct from attitude towards 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). Each child was individually administered a 24 item attitude measure, which contained 12 items assessing attitude towards writing and 12 parallel items for reading. Students also wrote a narrative about a personal event in their life. A factor analysis of the 24 item attitude measure provided evidence that generally support the contention that writing and reading attitudes are separable constructs for young beginning writers, as it yielded three factors: a writing attitude factor with 9 items, a reading attitude factor with 9 parallel items, and an attitude about literacy interactions with others factor containing 4 items (2 items in writing and 2 parallel items in reading). Further validation that attitude towards writing is a separable construct from attitude towards reading was obtained at the third-grade level, where writing attitude made a unique and significant contribution, beyond the other two attitude measures, to the prediction of three measures of writing: quality, length, and longest correct word sequence. At the first-grade level, none of the 3 attitude measures predicted students' writing performance. Finally, girls had more positive attitudes concerning reading and writing than boys.

  16. Separation and characterization of oligomeric hindered amine light stabilizers using high-performance liquid chromatography with UV and quadrupole time-of-flight mass spectrometric detection.

    PubMed

    Hintersteiner, Ingrid; Reisinger, Michael; Himmelsbach, Markus; Buchberger, Wolfgang

    2016-03-01

    Hindered amine light stabilizers are an important class of stabilizers that protect synthetic polymers from degradation and thus from changing mechanical and optical properties. The current study presents an HPLC method capable of separating oligomeric hindered amine light stabilizers on a commercially available stationary phase, employing an MS-compatible novel mobile phase. Based on the exact masses observed with Q-TOF-MS, a comprehensive characterization of five different types of oligomeric hindered amine light stabilizers was achieved, leading to structural information not included in the datasheets provided by the suppliers. For the different investigated hindered amine light stabilizers, a number of recurring units up to 17 and a molecular weight of 5200 g/mol were detected. Furthermore, the analysis of stabilizer extracts of processed polypropylene samples containing different types of hindered amine light stabilizers revealed significant differences in the oligomeric pattern between standards and polymer samples. Thus, changes in the analytes' oligomeric pattern resulting from processing or aging of polymer materials can be monitored with the presented method. PMID:26778637

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

    SciTech Connect

    Chen, W.

    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.

  18. Enzyme separation techniques for the study of growth of cells from layers of bovine dental pulp.

    PubMed

    Miller, W A; Everett, M M; Freedman, J T; Feagans, W C; Cramer, J F

    1976-08-01

    Effects of the enzymes trypsin, papain, bromelains and ficin on bovine dental pulp tissue were studied. Minced or whole pulps were subjected to each enzyme at 17 degrees, 20 degrees and 37 degrees C for set time intervals, after which aliquots of supernatant fluid were removed for cell counts and viability tests. Pooled samples were subsequently cultured as monolayers in Eagle's MEM plus 10% calf serum. The dissociation characteristics were quite distinct for each enzyme, although quite similar between minced and whole pulp. A parallel histological study was made of the residual pulp tissue. Ficin was found to be the most suitable enzyme for future studies on the growth of isolated pulp cells from various layers of the bovine pulp, due to its even rate of cell removal, and the good initial viability and subsequent growth of the separated cells in monolayer culture. Further studies on ficin may show that it is more suitable for enzymatic separation of tissues generally than the more commonly used trypsin, a major advantage being its use in media containing Ca2+ and Mg2+.

  19. Bioremediation of zinc using Desulfotomaculum nigrificans: bioprecipitation and characterization studies.

    PubMed

    Radhika, V; Subramanian, S; Natarajan, K A

    2006-11-01

    Desulfotomaculum nigrificans, a typical sulfate reducing bacterium (SRB) was successfully grown in the presence of 12-210 mg/L of zinc. Complete bioremoval of zinc was achieved in 2 days for 12 mg/L while the bioremoval efficiency was about 70% in 40 days in the presence of 210 mg/L initial concentration of zinc, attesting to the inhibition of bacterial cell growth at higher zinc concentrations. The bioremoval mechanism was predominantly governed by bioprecipitation with biosorption contributing to a minor extent. The amount of protein present in the extracellular secretions obtained by growth of SRB in modified Baars' medium devoid of iron was the highest followed by those obtained in the presence of zinc or iron, in that order. Bioremediation studies carried out using a specially designed set-up, facilitating the transfer of biogenically produced hydrogen sulfide gas to a separate precipitation assembly, confirmed that zinc could be successfully precipitated from its corresponding sulfate solution, varying in concentration from 10 to 20,000 mg/L. Detailed characterization of the various zinc sulfide precipitates by EDAX and X-ray diffraction analysis conformed to wurtzite structure. The isoelectric points of high purity zinc sulfide and that of chemically synthesized, biogenically produced and zinc sulfide precipitated using bacterially produced hydrogen sulfide gas (BPH-ZnS) were located at pH 3, 7.8, 2.8 and 8, respectively.

  20. A numerical and experimental study of the effects of dynamic roughness on laminar leading edge separation

    NASA Astrophysics Data System (ADS)

    Gall, Peter D.

    The aircraft industry, as a whole, has been deeply concerned with improving the aerodynamic efficiency of current and future flight vehicles, particularly in the commercial and military markets. However, of particular interest to the field of aerodynamics is the elusive concept of a workable flow control mechanism. Effective flow control is a concept which if properly applied can increase aerodynamic efficiency. Various concepts and ideas to obtain successful flow control have been studied in an attempt to reap these rewards. Some examples include boundary layer blowing (steady and periodic), suction, and compliant walls for laminar flow control. The overall goal of flow control is to increase performance by increasing lift, reducing drag, and delaying or eliminating leading edge separation. The specific objectives of flow control are to (1) delay or eliminate flow separation, (2) delay boundary layer transition, and (3) and reduce skin friction drag. The purpose of this research is to investigate dynamic roughness as a novel method of flow control technology for external boundary layer flows. As opposed to standard surface roughness, dynamic roughness incorporates small time dependent perturbations to the surface of the airfoil. These surface perturbations are actual humps and/or ridges on the surface of the airfoil that are on the scale of the laminar boundary, and oscillate with an unsteady motion. Research has shown that this can provide a means to modify the instantaneous and mean velocity profile near the wall and favorably control the existing state of the boundary layer. Several flow control parameters were studied including dynamic roughness frequency, amplitude, and geometry. The results of this study have shown, both numerically and experimentally, that dynamic roughness can provide an effective means for eliminating both a short and long laminar separation bubble and possibly prove a viable alternative in effective flow control, hence reaping some of

  1. 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

    2011-09-01

    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.

  2. 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.

  3. 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.

  4. Studies on stannic selenoarsenate. II. Separation of uranium from numerous metal ions

    SciTech Connect

    Nabi, S.A.; Siddiqi, Z.M.; Rao, R.A.K.

    1982-12-01

    Stannic selenoarsenate has been synthesized by adding 0.05 M sodium selenite and 0.05 M sodium arsenate to a 0.05 M solution of stannic chloride in a volume ratio of 1:1:1 at pH 1. A tentative structure has been proposed on the basis of chemical composition, pH titrations, and infrared and thermogravimetric analyses. Distribution coefficients of several metal ions have been studied in hydrochloric acid, citric acid, ammonium citrate-citric acid, and water-dioxane systems. The unusual adsorption behavior or uranium has been utilized for its quantitative separation from several metal ions.

  5. Kinetics of microphase separation in block copolymers: A molecular-dynamics study

    NASA Astrophysics Data System (ADS)

    Singh, Awaneesh; Krishnan, Raishma; Puri, Sanjay

    2015-01-01

    We study the kinetics of microphase separation in block copolymers (BCPs) via molecular-dynamics (MD) simulations in d = 3. The BCPs consist of AnBm polymer chains. In the early stages, the BCP segregation is analogous to usual spinodal decomposition in fluid or polymer mixtures. At late times, the BCP evolution freezes into a micro-scale morphology dictated by the n : m ratio, e.g., lamellar, cylindrical, droplet, etc. We investigate the crossovers in a) the scaling forms of the correlation function and structure factor; and b) the domain growth law.

  6. Atomic force microscopy studies of domain structures in phase-separated monolayers

    NASA Astrophysics Data System (ADS)

    Xiao, Shou-Jun; Wu, Hai-Ming; Yang, Xiao-Min; Wei, Yu; Tai, Zi-Hou; Sun, Xing-Zhong

    1994-10-01

    Domain structures were studied with atomic force microscopy (AFM) in binary phase-separated monolayer films composed of 5, 10, 15-triphenyl-20-(4-dl-α-phenylalanylamindo) phenyl porphyrin (TPPP) and one of a series of fatty acids which are arachidic acid (AA), palmitic acid (PA), and lauric acid (LA). The liquid-condensed (LC) domain structures of AA and PA were observed in their corresponding mixed monolayers. However, instead of the fatty acid domain, a liquid-expanded (LE) domain structure of TPPP appears in the mixed monolayer of LA/TPPP.

  7. 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

  8. Effects of sampling and mineral separation on accuracy of detrital zircon studies

    NASA Astrophysics Data System (ADS)

    SláMa, JiřÃ.­; KošLer, Jan

    2012-05-01

    We investigated some of the sampling and mineral separation biases that affect the accuracy of detrital zircon provenance studies. The study has been carried on a natural catchment in the Scottish Highlands that represents a simple two-component source system and on samples of synthetic sediment prepared for this study to test the effects of heavy mineral separation on the resulting zircon age spectra. The results suggest that zircon fertility of the source rocks and physical properties of zircon represent the most important factors affecting the distribution of zircon age populations in the stream sediments. The sample preparation and selection of zircons for analysis may result in preferential loss of information from small zircon grains. Together with the preference for larger crystals during handpicking, it can result in several-fold difference compared to the real age distribution in the sediment sample. These factors appear to be more important for the reproducibility of zircon age spectra than is the number of zircon grains analyzed per sample.

  9. 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.

  10. 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.

  11. Immunomagnetic separation of Salmonella with tailored magnetic micro and nanocarriers. A comparative study.

    PubMed

    Brandão, Delfina; Liébana, Susana; Campoy, Susana; Alegret, Salvador; Isabel Pividori, María

    2015-10-01

    This paper addresses a comparative study of immunomagnetic separation of Salmonella using micro and nano-sized magnetic carriers. In this approach, nano (300 nm) and micro (2.8 μm) sized magnetic particles were modified with anti-Salmonella antibody to pre-concentrate the bacteria from the samples throughout an immunological reaction. The performance of the immunomagnetic separation on the different magnetic carriers was evaluated using classical culturing, confocal and scanning electron microscopy to study the binding pattern, as well as a magneto-actuated immunosensor with electrochemical read-out for the rapid detection of the bacteria in spiked milk samples. In this approach, a second polyclonal antibody labeled with peroxidase as electrochemical reporter was used. The magneto-actuated electrochemical immunosensor was able to clearly distinguish between food pathogenic bacteria such as Salmonella enterica and Escherichia coli, showing a limit of detection (LOD) as low as 538 CFU mL(-1) and 291 CFU mL(-1) for magnetic micro and nanocarriers, respectively, in whole milk, although magnetic nanoparticles showed a noticeable higher matrix effect and higher agglomeration effect. These LODs were achieved in a total assay time of 1h without any previous culturing pre-enrichment step. If the samples were pre-enriched for 8 h, the magneto immunosensor based on the magnetic nanoparticles was able to detect as low as 1 CFU in 25 mL of milk (0.04 CFU mL(-1)). PMID:26078149

  12. Immunomagnetic separation of Salmonella with tailored magnetic micro and nanocarriers. A comparative study.

    PubMed

    Brandão, Delfina; Liébana, Susana; Campoy, Susana; Alegret, Salvador; Isabel Pividori, María

    2015-10-01

    This paper addresses a comparative study of immunomagnetic separation of Salmonella using micro and nano-sized magnetic carriers. In this approach, nano (300 nm) and micro (2.8 μm) sized magnetic particles were modified with anti-Salmonella antibody to pre-concentrate the bacteria from the samples throughout an immunological reaction. The performance of the immunomagnetic separation on the different magnetic carriers was evaluated using classical culturing, confocal and scanning electron microscopy to study the binding pattern, as well as a magneto-actuated immunosensor with electrochemical read-out for the rapid detection of the bacteria in spiked milk samples. In this approach, a second polyclonal antibody labeled with peroxidase as electrochemical reporter was used. The magneto-actuated electrochemical immunosensor was able to clearly distinguish between food pathogenic bacteria such as Salmonella enterica and Escherichia coli, showing a limit of detection (LOD) as low as 538 CFU mL(-1) and 291 CFU mL(-1) for magnetic micro and nanocarriers, respectively, in whole milk, although magnetic nanoparticles showed a noticeable higher matrix effect and higher agglomeration effect. These LODs were achieved in a total assay time of 1h without any previous culturing pre-enrichment step. If the samples were pre-enriched for 8 h, the magneto immunosensor based on the magnetic nanoparticles was able to detect as low as 1 CFU in 25 mL of milk (0.04 CFU mL(-1)).

  13. 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%.

  14. 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%. PMID:26729262

  15. 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.

  16. 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

  17. 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.

  18. 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.

  19. Experimental and Numerical Study of a Transitional Two-Dimensional Separation Bubble

    NASA Astrophysics Data System (ADS)

    Bakchinov, A. A.; Häggmark, C. P.; Alfredsson, P. H.; Hildings, C.; Henningson, D. S.

    1997-11-01

    A transitional two-dimensional separation bubble was created on a flat plate in the MTL wind tunnel using an adjustable hump at the upper wall to establish the pressure gradient. Linear and nonlinear development of natural and artificially introduced wave packets in the boundary layer was studied using hot wire anemometry. In the vicinity of the source TS-waves typical for the Blasius boundary layer were observed. A third maximum in between the two maxima of the TS-wave amplitude profile was found to be associated with an inflectional streamwise mean velocity profile in the adverse pressure gradient and separation regions. Both velocity correlation measurements and smoke visualization revealed that the unsteady vortical structure was still two-dimensional just prior to the reattachment of the shear layer, whereas both steady and unsteady flow structures in the reattachment region was found to be essentially three-dimensional. In the numerical simulation good agreement in mean flow parameters was found when the measured normal velocity was used as free stream boundary conditions. In those calculations the growth characteristics of small amplitude two-dimensional disturbances also agreed well with the measured values.

  20. A study on fear memory retrieval and REM sleep in maternal separation and isolation stressed rats.

    PubMed

    Sampath, Dayalan; Sabitha, K R; Hegde, Preethi; Jayakrishnan, H R; Kutty, Bindu M; Chattarji, Sumantra; Rangarajan, Govindan; Laxmi, T R

    2014-10-15

    As rapid brain development occurs during the neonatal period, environmental manipulation during this period may have a significant impact on sleep and memory functions. Moreover, rapid eye movement (REM) sleep plays an important role in integrating new information with the previously stored emotional experience. Hence, the impact of early maternal separation and isolation stress (MS) during the stress hyporesponsive period (SHRP) on fear memory retention and sleep in rats were studied. The neonatal rats were subjected to maternal separation and isolation stress during postnatal days 5-7 (6h daily/3d). Polysomnographic recordings and differential fear conditioning was carried out in two different sets of rats aged 2 months. The neuronal replay during REM sleep was analyzed using different parameters. MS rats showed increased time in REM stage and total sleep period also increased. MS rats showed fear generalization with increased fear memory retention than normal control (NC). The detailed analysis of the local field potentials across different time periods of REM sleep showed increased theta oscillations in the hippocampus, amygdala and cortical circuits. Our findings suggest that stress during SHRP has sensitized the hippocampus-amygdala-cortical loops which could be due to increased release of corticosterone that generally occurs during REM sleep. These rats when subjected to fear conditioning exhibit increased fear memory and increased fear generalization. The development of helplessness, anxiety and sleep changes in human patients, thus, could be related to the reduced thermal, tactile and social stimulation during SHRP on brain plasticity and fear memory functions.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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. PMID:26208980

  8. Synthesis, characterization of low density polyhydroxy polyurethane foam and its application for separation and determination of gold in water and ores samples.

    PubMed

    Moawed, E A; El-Shahat, M F

    2013-07-25

    In this work, a new type of sorbent (low density polyhydroxy polyurethane Foam, LPPF) was synthesis by using water hydrolysis of polyurethanediazonium chloride salt. LPPF was characterized using different tools e.g. elemental analysis, UV-vis and IR spectra, TGA, SEM, density and pHZPC. It was tested for separation, preconcentration and determination of gold in environmental samples using batch and dynamic techniques. The sorption experimental data was fitted by the pseudo-first kinetic mathematical equation (R(2)=0.991). The sorption rate of the Au (III) ions is very fast, the half-life (t1/2)≈34 s. The equilibrium process is well described by the Freundlich isotherm model, the R(2) value is 0.967, which attributed to the heterogeneous surface structure of the LPPF. The breakthrough capacity of LPPF and the recovery of gold ions were 0.36 mmol g(-1) (70.5 mg g(-1)) and 99-100%, respectively. The lower detection limit of gold by using spectrophotometric method is 3.3 ng L(-1) with preconcentration factors≈450 (RSD∼1.66%, n=4). The values of ΔG and ΔH for the sorption of gold onto LPPF were -12.5 and -103.5 kJ mol(-1), respectively, which indicate that the sorption of Au (III) onto LPPF is spontaneous and exothermic reaction. The obtained results indicate that the ion chelation and ion association might be the most probable mechanism of gold sorption onto LPPF. The study shows LPPF has the potential of application as an efficient sorbent for the extraction and determination of gold in water, gold alloys pharmaceutical and granite samples. PMID:23845501

  9. Synthesis, characterization of low density polyhydroxy polyurethane foam and its application for separation and determination of gold in water and ores samples.

    PubMed

    Moawed, E A; El-Shahat, M F

    2013-07-25

    In this work, a new type of sorbent (low density polyhydroxy polyurethane Foam, LPPF) was synthesis by using water hydrolysis of polyurethanediazonium chloride salt. LPPF was characterized using different tools e.g. elemental analysis, UV-vis and IR spectra, TGA, SEM, density and pHZPC. It was tested for separation, preconcentration and determination of gold in environmental samples using batch and dynamic techniques. The sorption experimental data was fitted by the pseudo-first kinetic mathematical equation (R(2)=0.991). The sorption rate of the Au (III) ions is very fast, the half-life (t1/2)≈34 s. The equilibrium process is well described by the Freundlich isotherm model, the R(2) value is 0.967, which attributed to the heterogeneous surface structure of the LPPF. The breakthrough capacity of LPPF and the recovery of gold ions were 0.36 mmol g(-1) (70.5 mg g(-1)) and 99-100%, respectively. The lower detection limit of gold by using spectrophotometric method is 3.3 ng L(-1) with preconcentration factors≈450 (RSD∼1.66%, n=4). The values of ΔG and ΔH for the sorption of gold onto LPPF were -12.5 and -103.5 kJ mol(-1), respectively, which indicate that the sorption of Au (III) onto LPPF is spontaneous and exothermic reaction. The obtained results indicate that the ion chelation and ion association might be the most probable mechanism of gold sorption onto LPPF. The study shows LPPF has the potential of application as an efficient sorbent for the extraction and determination of gold in water, gold alloys pharmaceutical and granite samples.

  10. Numerical study of boundary layer separation control using magnetogasdynamic plasma actuators

    SciTech Connect

    Kalra, Chiranjeev S.; Shneider, Mikhail N.; Miles, Richard B.

    2009-10-15

    In this study, an efficient, time dependent, two-dimensional Navier-Stokes numerical code for shockwave boundary layer interaction in air is developed. Nonthermal surface plasma actuation is evaluated for effective shockwave induced boundary layer separation control within supersonic inlets. Specifically, high speed magnetogasdynamic plasma actuators are of interest. In these, localized ionization is produced close to the wall surface and then the flow is accelerated using strong magnetic fields. To replicate the experiments done at large boundary layer thickness, the code is divided into time independent and time dependent regimes to significantly reduce computation time. Computational results are in good agreement with experiments in terms of the flow structure as shown by Schlieren imaging, acetone planar laser scattering, and the static pressure profile on the test section wall.

  11. Colloidally separated samples from Allende residues - Noble gases, carbon and an ESCA-study

    NASA Technical Reports Server (NTRS)

    Ott, U.; Kronenbitter, J.; Flores, J.; Chang, S.

    1984-01-01

    Results are presented which strengthen the hypothesis of heterogeneity among the carbon- and nitrogen-bearing phases of the Allende meteorite. These data also highlight the possibility of performing physical separations yielding samples in which some of the noble gas- and carbon-bearing phases are extraordinarily predominant over others. The conclusion, based on mass and isotope balance arguments, that a significant portion of the carbonaceous matter in Allende is likely to be gas-poor or gas-free need not weaken the case for carbonaceous carriers for the major noble gas components. The concept that acid-soluble carbonaceous phases contain a multiplicity of components, each of which may have formed under a multiplicity of different physical-chemical conditions, is reemphasized by the results of the present study.

  12. 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.

  13. 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.

  14. Study of selective heating at ion cyclotron resonance for the plasma separation process

    NASA Astrophysics Data System (ADS)

    Compant La Fontaine, A.; Pashkovsky, V. G.

    1995-12-01

    The plasma separation process by ion cyclotron resonance heating (ICRH) is studied both theoretically and experimentally on two devices: the first one called ERIC (Ion Cyclotron Resonance Experiment) at Saclay (France) [P. Louvet, Proceedings of the 2nd Workshop on Separation Phenomena in Liquids and Gases, Versailles, France, 1989, edited by P. Louvet, P. Noe, and Soubbaramayer (Centre d'Etudes Nucléaires de Saclay and Cité Scientifique Parcs et Technopoles, Ile de France Sud, France, 1989), Vol. 1, p. 5] and the other one named SIRENA at the Kurchatov Institute, Moscow, Russia [A. I. Karchevskii et al., Plasma Phys. Rep. 19, 214 (1993)]. The radio frequency (RF) transversal magnetic field is measured by a magnetic probe both in plasma and vacuum and its Fourier spectrum versus the axial wave number kz is obtained. These results are in agreement with the electromagnetic (EM) field calculation model based on resolution of Maxwell equations by a time-harmonic scheme studied here. Various axial boundary conditions models used to compute the EM field are considered. The RF magnetic field is weakly influenced by the plasma while the electric field components are strongly disturbed due to space-charge effects. In the plasma the transversal electric field is enhanced and the kz spectrum is narrower than in vacuum. The calculation of the resonant isotope heating is made by the Runge-Kutta method. The influence of ion-ion collisions, inhomogeneity of the static magnetic field B0, and the RF transversal magnetic field component on the ion acceleration is examined. These results are successfully compared with experiments of a minor isotope 44Ca heating measurements, made with an energy analyzer.

  15. Study of selective heating at ion cyclotron resonance for the plasma separation process

    SciTech Connect

    Compant La Fontaine, A.

    1995-12-01

    The plasma separation process by ion cyclotron resonance heating (ICRH) is studied both theoretically and experimentally on two devices: the first one called ERIC (Ion Cyclotron Resonance Experiment) at Saclay (France) [P. Louvet, {ital Proceedings} {ital of} {ital the} 2{ital nd} {ital Workshop} {ital on} {ital Separation} {ital Phenomena} {ital in} {ital Liquids} {ital and} {ital Gases}, Versailles, France, 1989, edited by P. Louvet, P. Noe, and Soubbaramayer (Centre d`Etudes Nucleaires de Saclay and Cite Scientifique Parcs et Technopoles, Ile de France Sud, France, 1989), Vol. 1, p. 5] and the other one named SIRENA at the Kurchatov Institute, Moscow, Russia [A. I. Karchevskii {ital et} {ital al}., Plasma Phys. Rep. {bold 19}, 214 (1993)]. The radio frequency (RF) transversal magnetic field is measured by a magnetic probe both in plasma and vacuum and its Fourier spectrum versus the axial wave number {ital k}{sub {ital z}} is obtained. These results are in agreement with the electromagnetic (EM) field calculation model based on resolution of Maxwell equations by a time-harmonic scheme studied here. Various axial boundary conditions models used to compute the EM field are considered. The RF magnetic field is weakly influenced by the plasma while the electric field components are strongly disturbed due to space-charge effects. In the plasma the transversal electric field is enhanced and the {ital k}{sub {ital z}} spectrum is narrower than in vacuum. The calculation of the resonant isotope heating is made by the Runge--Kutta method. The influence of ion--ion collisions, inhomogeneity of the static magnetic field {ital B}{sub 0}, and the RF transversal magnetic field component on the ion acceleration is examined. These results are successfully compared with experiments of a minor isotope {sup 44}Ca heating measurements, made with an energy analyzer. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  16. 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. PMID:14640746

  17. 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…

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. TANK 7 CHARACTERIZATION AND WASHING STUDIES

    SciTech Connect

    Lambert, D.; Pareizs, J.; Click, D.

    2010-02-04

    A 3-L PUREX sludge sample from Tank 7 was characterized and then processed through a series of inhibited water washes to remove oxalate, sodium, and other soluble ions. Current plans use Tank 7 as one of the feed sources for Sludge Batch 7 (SB7). Tank 7 is high in oxalate due to the oxalic acid cleaning of the sludge heels from Tanks 5 and 6 and subsequent transfer to Tank 7. Ten decant and nine wash cycles were performed over a 47 day period at ambient temperature. Initially, seven decants and seven washes were completed based on preliminary estimates of the number of wash cycles required to remove the oxalate in the sludge. After reviewing the composition data, SRNL recommended the completion of 2 or 3 more decant/wash cycles to ensure all of the sodium oxalate had redissolved. In the first 7 washes, the slurry oxalate concentration was 12,300 mg/kg (69.6% oxalate removal compared to 96.1% removal of the other soluble ions). After all ten decants were complete, the slurry oxalate concentration was 3,080 mg/kg (89.2% oxalate removal compared to 99.0% of the other soluble ions). The rate of dissolution of oxalate increased significantly with subsequent washes until all of the sodium oxalate had been redissolved after seven decant/wash cycles. The measured oxalate concentrations agreed very well with LWO predictions for washing of the Tank 7 sample. Highlights of the analysis and washing of the Tank 7 sample include: (1) Sodium oxalate was detected in the as-received filtered solids. 95% of the oxalate was insoluble (undissolved) in the as-received slurry. (2) No sodium oxalate was detected in the post-wash filtered solids. (3) Sodium oxalate is the last soluble species that redissolves during washing with inhibited water. In order to significantly reduce the sodium oxalate concentration, the sludge must be highly washed, leaving the other soluble anions and cations (including sodium) very low in concentration. (4) The post-wash slurry had 1% of the soluble anions

  4. Liquid effluent study: Ground water characterization data

    SciTech Connect

    Not Available

    1990-08-01

    This report is a support document to the Liquid Effluent Study Final Project Report (WHC 1990c). The focus is on sampling and analysis rationale, quality assurance (QA), data validation, and sampling conditions for the groundwater quality assessment. Interpretation of the groundwater data is provided in the final project report. 20 refs., 5 figs., 2 tabs.

  5. 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…

  6. 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

    2015-01-01

    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. PMID:26411597

  7. 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.

  8. 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.

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

    DOE PAGESBeta

    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.; et al

    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

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

    PubMed Central

    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.

    2015-01-01

    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. PMID:26411597

  11. Visualized study on the interaction between single bubbles and curved solid surface in flotation separation process.

    PubMed

    Yang, Liwei; Zhao, Yue; Yang, Jingjing; Li, Yanpeng; Meng, Qinglong

    2014-01-01

    The present study has been devoted to bubble-curved solid surface interaction in water, which is critical to the separation of suspended particles by air flotation. For this purpose, two particular stages of the interaction (collision and attachment) have been examined visually using high-speed photography in a laboratory-scale flotation column. The effects of the surface material and surfactant concentration on these two stages have been also studied quantitatively. The considered solid materials are the cleaned glass as hydrophilic surface and Teflon as hydrophobic surface. The experimental results show that the presence of surfactant significantly affects the collision and rebound process of a gas bubble, while there is no obvious effect of the surface material on the rebound process. An increase in surfactant concentration has been observed to suppress the rebound number and maximal distance of the bubble from the surface. Moreover, the three-phase contact time of the bubble is a strong function of the surfactant concentration and surface hydrophobicity as well as of the bubble diameter. Another important finding is that the bubble attachment is only observed at the hydrophobic Teflon surface below the surfactant CMC (critical micelle concentration). Results of this study are relevant for deep understanding of the attachment mechanism and to determine the proper conditions for a selective flotation process.

  12. Separating stressor influences from environmental variability: eight case studies from aquatic and terrestrial ecosystems

    SciTech Connect

    Luoma, Samuel N.; Clements, Will; Gerritsen, Jeroen; Hatch, Audrey; Jepson, Paul; Reynoldson, Trefor; Thom, Ronald M.

    2001-12-03

    It can be difficult to unambiguously establish the influences of a particular stressor or group of stressors in a complex ecosystem, except, perhaps, when the effects are extreme (Luoma and Carter, 1991). Yet this is a critical problem we face when attempting to understand the influences of human activities on ecosystems. Single experiments or studies are rarely adequate to establish cause and effect in complex ecosystems, and many of the individual approaches available to demonstrate stressor effects have important inadequacies. A multi-faceted body of work is usually at the center of most examples where stressor effects are explained. In this chapter seven case studies are presented where effects or influences of multiple stressors were explained and separated from natural variability. The goal of this chapter is to demonstrate that identification of stressor effects is tractable, although not necessarily simple; and to illustrate some specific strategies that have worked. We also present one case study where the quest for cause and effect is just beginning, to illustrate the range of challenges involved as a body of work begins to be established. The examples are from several different fields of ecology, they cover a variety of scales and a mix of disciplines.

  13. Mathematical study of hydrocyclone dispersed phase separation in clearing viscoplastic drilling fluids

    NASA Astrophysics Data System (ADS)

    Matvienko, O. V.; Evtyushkin, E. V.

    2011-03-01

    On the basis of rheodynamic equations, a numerical investigation of the flow structure of a viscoplastic fluid and dispersed phase separation in a hydrocyclone has been carried out. The proposed mathematical model will make it possible to calculate the separation indices and the velocity, pressure, and particle density fields in the apparatus.

  14. CANTON CAFO FIELD SITE STUDY - SITE CHARACTERIZATION AND CONTAMINANT IMPACTS

    EPA Science Inventory

    This presentation of CAFO research concerning the Canton CAFO field site study, including its characterization and contaminant impacts, was given at a NRMRL program review discussion of the CAFO Research Program.

  15. 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.

  16. Separation, detection and characterization of nanomaterials in municipal wastewaters using hydrodynamic chromatography coupled to ICPMS and single particle ICPMS.

    PubMed

    Proulx, Kim; Hadioui, Madjid; Wilkinson, Kevin J

    2016-07-01

    Engineered nanoparticles (ENP) are increasingly being incorporated into consumer products and reaching the environment at a growing rate. Unfortunately, few analytical techniques are available that allow the detection of ENP in complex environmental matrices. The major limitations with existing techniques are their relatively high detection limits and their inability to distinguish ENP from other chemical forms (e.g. ions, dissolved) or from natural colloids. Of the matrices that are considered to be a priority for method development, ENP are predicted to be found at relatively high concentrations in wastewaters and wastewater biosolids. In this paper, we demonstrate the capability of hydrodynamic chromatography (HDC) coupled to inductively coupled plasma mass spectrometry (ICPMS), in its classical and single particle modes (SP ICPMS), to identify ENP in wastewater influents and effluents. The paper first focuses on the detection of standard silver nanoparticles (Ag NP) and their mixtures, showing that significant dissolution of the Ag NP was likely to occur. For the Ag NP, detection limits of 0.03 μg L(-1) were found for the HDC ICPMS whereas 0.1 μg L(-1) was determined for the HDC SP ICPMS (based on results for the 80 nm Ag NP). In the second part of the paper, HDC ICPMS and HDC SP ICPMS were performed on some unspiked natural samples (wastewaters, river water). While nanosilver was below detection limits, it was possible to identify some (likely natural) Cu nanoparticles using the developed separation technology. PMID:26970748

  17. Separation, characterization and sexual heterogeneity of multiple putative odorant-binding proteins in the honeybee Apis mellifera L. (Hymenoptera: Apidea).

    PubMed

    Danty, E; Arnold, G; Huet, J C; Huet, D; Masson, C; Pernollet, J C

    1998-02-01

    According to precise molar mass determined by mass spectrometry and N-terminal sequence, some 25 odorant-binding-like proteins were characterized from the antennae and legs of worker and drone honeybees. Antennal specific proteins, composed of six different molecules, were classified into three subclasses according to N-terminal sequence homology. The major sexual difference was shown to lie in the relative abundance of these antennal specific proteins and in the occurrence of a drone-specific isoform. At least 19 other related proteins were found to occur in antennae and legs, forming another class showing homology with insect OBP. Genotype comparison of two honeybee races revealed a variability limited to this second class. Provided that these odorant-binding-like proteins are indeed able to bind odorants or pheromones, the question of whether their peculiar multiplicity contributes to the remarkable capacity of the honeybee to discriminate among a wide range of odor molecules is raised.

  18. Structural studies of the phase separation of amorphous FexGe100-x alloys

    NASA Astrophysics Data System (ADS)

    Lorentz, Robert D.; Bienenstock, Arthur; Morrison, Timothy I.

    1994-02-01

    Small-angle x-ray scattering and x-ray-absorption near-edge spectroscopy (XANES) experiments have been performed on amorphous FexGe100-x alloys over the composition range 0<=x<=72. The observed small-angle x-ray-scattering patterns were compared both with those calculated for a model assuming segregation of the alloys into particular phases and with scattering patterns calculated for voids in a homogeneous matrix. The x-ray-absorption near-edge-structure data were used to test for phase separation. No large-scale phase separation is observed in the semiconductor-metal transition region (15-25 at. % Fe), but fine-scale, kinetically limited phase separation or other types of composition fluctuations cannot be ruled out. The results also indicate that phase separation occurs for alloys with 37<=x<=72, with data consistent with separation into amorphous FeGe2 and Fe3Ge. Thus, ferromagnetic moment formation occurs in the phase-separated region, with the transition composition (40-43 at. % Fe) probably linked to a-Fe3Ge percolation, as hypothesized by Janot for the related FexSn100-x system. This phase separation explains the Mossbauer observation of ``magnetic'' and ``nonmagnetic'' Fe atoms in these alloys.

  19. An Experimental Study of Ice-Bed Separation during Sliding over a Hard Bed (Invited)

    NASA Astrophysics Data System (ADS)

    Iverson, N. R.; Petersen, B. B.

    2010-12-01

    Separation of sliding ice from hard beds plays a central role in theories of subglacial hydrology, sliding and surging, and erosion of subglacial bedrock. Despite a half-century of interest in cavities at glacier beds, there are no data that establish relationships between 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 drag on the bed, bedrock geometry, and cavity size. Cavity growth and shrinkage have been commonly estimated from glacier surface velocities but usually by making the uncertain assumption that vertical ice strain is uniform with depth. These problems are avoided by studying sliding and ice-bed separation experimentally with a recently constructed laboratory device. The device rotates a large confined ring (0.9 m O.D., 0.2 m wide , 0.2 m thick) of synthetic ice across a rigid or soft horizontal bed at a constant speed or shear stress, while applying a downward stress. A bath with circulating fluid, regulated to ~0.01 °C., surrounds the ice chamber. This bath keeps the ice at its pressure-melting temperature and the melt rate low. Initial experiments have been with a rigid bed, consisting of steps 0.18 m long and 0.035 m high at the ice-ring centerline, with stoss surfaces inclined uniformly at 11° and vertical lee surfaces. The steps are plastic of low thermal conductivity, so that regelation can be neglected. Imposed steady slip rates have, to date, ranged from ~20 to 200 m/a, under an effective pressure of ~1000 kPa. Cavities of steady size develop over periods of ~10-60 hours, depending upon the sliding speed and initial cavity size. Cavities do not change their size monotonically after a change in slip velocity but oscillate slowly one or more times about their steady size before attaining it. Cavities initiate at step edges and have weakly sigmoidal roofs. Measured drag on the bed is independent of slip

  20. Partition separation and characterization of the polyhydroxyalkanoates synthase produced from recombinant Escherichia coli using an aqueous two-phase system.

    PubMed

    Lan, John Chi-Wei; Yeh, Chun-Yi; Wang, Chih-Chi; Yang, Yu-Hsuan; Wu, Ho-Shing

    2013-10-01

    Polyhydroxyalkanoates (PHAs) are renewable and biodegradable polyesters which can be synthesized either by numerous of microorganisms in vivo or synthase in vitro. The synthesis of PHAs in vitro requires an efficient separation for high yield of purified enzyme. The recombinant Escherichia coli harboring phaC gene derived from Ralstonia eutropha H16 was cultivated in the chemically defined medium for overexpression of synthase in the present work. The purification and characteristics of PHA synthase from clarified feedstock by using aqueous two-phase systems (ATPS) was investigated. The optimized concentration of ATPS for partitioning PHA synthase contained polyethylene glycol 6000 (30%, w/w) and potassium phosphate (8%, w/w) with 3.25 volume ratio in the absence of NaCl at pH 8.7 and 4°C. The results showed that the partition coefficient of enzyme activity and protein content are 6.07 and 0.22, respectively. The specific activity, selectivity, purification fold and recovery of phaC(Re) achieved 1.76 U mg⁻¹, 29.05, 16.23 and 95.32%, respectively. Several metal ions demonstrated a significant effect on activity of purified enzyme. The purified enzyme displayed maximum relative activity as operating condition at pH value of 7.5 and 37°C. As compared to conventional purification processes, ATPS can be a promising technique applied for rapid recovery of PHA synthase and preparation of large quantity of PHA synthase on synthesis of P(3HB) in vitro.

  1. 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.

  2. 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.

  3. Particulate diesel-exhaust characterization study

    SciTech Connect

    Glaser, R.; Cooper, C.; Deye, G.; Ong, T.

    1983-01-01

    Several analyses were made of the diesel-exhaust particulates which were used in a study made to determine the effects of long-term exposure to coal dust and exhaust from diesel engines on laboratory animals. The diesel engine used was of a type used in underground-mining operations, and was equipped with a water scrubber in the exhaust line. Lipid chromatographic fluorescence detection of the solvent extracts of the diesel exhaust components showed fluorescing compounds covering a wide range of polarity to be present in the exhaust samples. Preparative fractions of solvent extracts of particulate diesel exhaust indicated that the majority of the mass recovered was in the nonpolar fraction. Sufficient quantities of nitroarenes were isolated for identification purposes; high-resolution mass spectroscopy with selected ion monitoring was used. 1-Nitropyrene and a nitrofluorene isomer were identified in several of the extract fractions. Both direct and enzyme-activated mutagens were present in the diesel particulate and scrubber water extract and the unextracted scrubber particulate. The authors conclude that the contents of the scrubber may represent a significant health hazard due to the presence of mutagens.

  4. A STUDY OF MULTISTAGE/MULTIFUNCTION COLUMN FOR FINE PARTICLE SEPARATION

    SciTech Connect

    Dr. Shiao-Hung Chiang

    1999-10-01

    A non-agitated multi-stage column was constructed and applied to wastewater treatment. Preliminary oil/water separation tests were performed. Excellent separation results verifies the multi-function feature of the multi-stage column. Hydrodynamic behavior is considered as the underlying cause for the separation performance. Therefore, a series of experiments were carried out to investigate the hydrodynamic parameters, including gas holdups and liquid circulating velocities. The experimental data will be used to create a mathematical model to simulate the multi-stage column process. The model will further shed light on the future scale-up of the MSTLFLO process.

  5. A Study of Multistage/Multifunction Column for Fine Particle Separation.

    SciTech Connect

    Chiang, S.

    1997-09-15

    A non-agitated multi-stage column was constructed and applied to wastewater treatment. Preliminary oil/water separation tests were performed. Excellent separation results verifies the multi-function feature of the multi-stage column. Hydrodynamic behavior is considered as the underlying cause for the separation performance. Therefore, a series of experiments were carried out to investigate the hydrodynamic parameters, including gas holdups and liquid circulating velocities. The experimental data will be used to create a mathematical model to simulate the multi-stage column process. The model will further shed light on the future scale-up of the MSTLFLO process.

  6. Structure and function of an inorganic-organic separator for electrochemical cells: Preliminary study

    NASA Technical Reports Server (NTRS)

    Bozek, J. M.

    1974-01-01

    The structure of a new separator material for electrochemical cells has been investigated. Investigation into details of the separator structure showed it to be multilayered and to consist mainly of a quasi-impervious organic skin, a porous region of mixed organic and inorganic material, and an area of nonuniformly treated substrate. The essential feature of the coating (slurry) is believed to be interconnected pores which allow ionic conductivity. The interconnected pores are believed to be formed by the interaction of the plasticizer and inorganic fibers. The major failure mode of silver zinc cells using such a separator (zinc nodules shorting adjacent plates) was investigated.

  7. A Comparative Study of Microphase Separation of Polyurethane Multiblock Copolymers with Different Soft Segment Chemistries.

    NASA Astrophysics Data System (ADS)

    Hernandez, Rebeca; Choi, Taeyi; Weksler, Jadwiga; Padsalgikar, Ajay; Xu, Lichong; Siedlecki, Christopher; Runt, James

    2008-03-01

    We focus in this study on three series of chemically well-defined polyurethanes (PUs) with the same hard segments (MDI-BDO) but different soft segment chemistries of interest in biomedical applications: 1000 g/mol aliphatic polycarbonate, polytetramethylenoxide and a mixed macrodiol of polydimethylsiloxane (PDMS) and polyhexamethylenoxide. Using quantitative small-angle X-ray scattering we demonstrate that the degree of hard/soft segment demixing varies greatly between the materials. For example, the PDMS-based copolymers exhibit a three phase, core-shell morphology, while the other copolymers exhibit a typical two phase structure. Additional analysis was conducted with a number of experimental probes including FTIR to assess inter- and intracomponent hydrogen bonding, and tapping mode AFM to characterize the nanoscale morphology.

  8. 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)

  9. 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

  10. 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

  11. Atomic-force-microscopy studies of phase separations in macromolecular systems

    NASA Astrophysics Data System (ADS)

    Kuznetsov, Yu. G.; Malkin, A. J.; McPherson, A.

    1998-09-01

    Atomic force microscopy (AFM) has been used to visualize events arising from the formation of intervening metastable phases at the surfaces of macromolecular crystals growing from solution. Crystals investigated were of the proteins canavalin, thaumatin, lipase, xylanase, and catalase, crystals of transfer RNA, and crystals of satellite tobacco mosaic virus. Two types of aggregates were observed. The first were small, linear and branched aggregates, perhaps fractile in structure. These were incorporated into growing crystals as impurities, and they produced defects of various kinds. The second aggregate form we infer to be liquid-protein droplets which were particularly evident in freshly mixed protein-precipitant solutions. Droplets, upon sedimentation, have two possible fates. In some cases they immediately restructured as crystalline multilayer stacks whose development was guided by and contiguous with the underlying lattice. These contributed to the ordered growth of the crystal by serving as sources of growth steps. In other cases, liquid-protein droplets formed distinct microcrystals, somehow discontinuous with the underlying lattice, and these were subsequently incorporated into the growing substrate crystal with the formation of defects. Scarring experiments with the AFM tip indicated that liquid-protein droplets with the potential to rapidly crystallize were a consequence of concentration instabilities near the crystal's surfaces. The AFM study suggests that phase separation and the appearance of aggregates having limited order is a common occurrence in supersaturated macromolecular solutions such as the protein-precipitant solutions used for crystallization.

  12. Experimental study of pedestrian inflow in a room with a separate entrance and exit

    NASA Astrophysics Data System (ADS)

    Liu, Xiaodong; Song, Weiguo; Fu, Libi; Fang, Zhiming

    2016-01-01

    Pedestrian inflow process frequently occurs in various pedestrian facilities in our daily life. Great importance should be attached to the study of this process. In this paper, we explore the pedestrian inflow process in a room with a separate entrance and exit. Two kinds of experiments are conducted: experiment 1 has no inactive persons and primarily focuses on analyzing the features of the normal pedestrian inflow process and analyzing the representative spatial parameters in the steady state, while experiment 2 involves the influence of the inactive persons. In order to quantitatively discuss the distribution of pedestrians in the steady state, we adopt several analytical methods, such as the Voronoi diagram method, proxemics, and point pattern analysis. Some features of the inflow process are captured. The distribution of pedestrians in the steady state is not uniform. The proxemics and attraction to the exit are both considered to affect pedestrians' distribution in the inflow process. The presence of inactive persons may have an impact on both the inflow and outflow processes. Practical suggestions are provided for the managers of pedestrian facilities.

  13. 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%.

  14. 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.

  15. A multi-method approach toward de novo glycan characterization: a Man-5 case study.

    PubMed

    Prien, Justin M; Prater, Bradley D; Cockrill, Steven L

    2010-05-01

    Regulatory agencies' expectations for biotherapeutic approval are becoming more stringent with regard to product characterization, where minor species as low as 0.1% of a given profile are typically identified. The mission of this manuscript is to demonstrate a multi-method approach toward de novo glycan characterization and quantitation, including minor species at or approaching the 0.1% benchmark. Recently, unexpected isomers of the Man(5)GlcNAc(2) (M(5)) were reported (Prien JM, Ashline DJ, Lapadula AJ, Zhang H, Reinhold VN. 2009. The high mannose glycans from bovine ribonuclease B isomer characterization by ion trap mass spectrometry (MS). J Am Soc Mass Spectrom. 20:539-556). In the current study, quantitative analysis of these isomers found in commercial M(5) standard demonstrated that they are in low abundance (<1% of the total) and therefore an exemplary "litmus test" for minor species characterization. A simple workflow devised around three core well-established analytical procedures: (1) fluorescence derivatization; (2) online rapid resolution reversed-phase separation coupled with negative-mode sequential mass spectrometry (RRRP-(-)-MS(n)); and (3) permethylation derivatization with nanospray sequential mass spectrometry (NSI-MS(n)) provides comprehensive glycan structural determination. All methods have limitations; however, a multi-method workflow is an at-line stopgap/solution which mitigates each method's individual shortcoming(s) providing greater opportunity for more comprehensive characterization. This manuscript is the first to demonstrate quantitative chromatographic separation of the M(5) isomers and the use of a commercially available stable isotope variant of 2-aminobenzoic acid to detect and chromatographically resolve multiple M(5) isomers in bovine ribonuclease B. With this multi-method approach, we have the capabilities to comprehensively characterize a biotherapeutic's glycan array in a de novo manner, including structural isomers at >/=0

  16. CD8+/FOXP3+-ratio in osteosarcoma microenvironment separates survivors from non-survivors: a multicenter validated retrospective study

    PubMed Central

    Fritzsching, Benedikt; Fellenberg, Joerg; Moskovszky, Linda; Sápi, Zoltan; Krenacs, Tibor; Machado, Isidro; Poeschl, Johannes; Lehner, Burkhard; Szendrõi, Miklos; Bosch, Antonio Llombart; Bernd, Ludger; Csóka, Monika; Mechtersheimer, Gunhild; Ewerbeck, Volker; Kinscherf, Ralf; Kunz, Pierre

    2015-01-01

    Osteosarcoma is the most common primary bone tumor characterized by juvenile onset, tumor heterogeneity, and early pulmonary metastasis. Therapeutic improvement stagnates since more than two decades. Unlike major malignancies, biomarkers as prognostic factors at time of diagnosis are missing. Disease rareness hampers study recruitment of patient numbers sufficient to outweigh tumor heterogeneity. Here, we analyzed in a multicenter cohort the osteosarcoma microenvironment to reduce effects of tumor cell heterogeneity. We hypothesized that quantitative ratios of intratumoral CD8+T-cells to FOXP3+T-cells (CD8+/FOXP3+-ratios) provide strong prognostic information when analyzed by whole-slide imaging in diagnostic biopsies. We followed recommendations-for-tumor-marker-prognostic-studies (REMARK). From 150 included cases, patients with complete treatment were identified and assigned to the discovery (diagnosis before 2004) or the validation cohort (diagnosis 2004–2012). Highly standardized immunohistochemistry of CD8+ and FOXP3+, which was validated by methylation-specific gene analysis, was performed followed by whole-slide analysis and clinical outcome correlations. We observed improved estimated survival in patients with CD8+/FOXP3+-ratios above the median (3.08) compared to patients with lower CD8+/FOXP3+-ratios (p = 0.000001). No patients with a CD8+/FOXP3+-ratio above the third quartile died within the observation period (median follow-up 69 mo). Multivariate analysis demonstrated independence from current prognostic factors including metastasis and response to neoadjuvant chemotherapy. Data from an independent validation cohort confirmed improved survival (p = 0.001) in patients with CD8+/FOXP3+-ratios above 3.08. Multivariate analysis proofed that this observation was also independent from prognostic factors at diagnosis within the validation cohort. Intratumoral CD8+/FOXP3+-ratio in pretreatment biopsies separates patients with prolonged survival from non

  17. 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.

  18. 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.

  19. Thermodynamic study of an unusual chiral separation. Propranolol enantiomers on an immobilized cellulase

    SciTech Connect

    Fornstedt, T.; Sajonz, P.; Guiochon, G. |

    1997-02-12

    The thermodynamics of interaction of (R)- and (S)-propranolol between an acetic acid buffer (pH = 4.7 and 5.5) and the protein cellobiohydrolase I immobilized on silica gel was studied between 5 and 45{degree}C. The equilibrium data were fitted to a biLangmuir adsorption isotherm with excellent agreement. One of the two Langmuir contributions is the same for both enantiomers and accounts for the nonspecific interactions between these compounds and most sites on the surfaces (type-I, nonselective sites). It has a large saturation capacity. The second contribution accounts for the chiral selective interactions (type-II sites). It has a lower monolayer capacity than the first. The interaction enthalpy and entropy on type-I sites are -1.1 kcal/mol and +0.1 cal/(mol K), respectively. For type-II sites, they are -1.9 kcal/mol and -2.6 cal/(mol K), respectively, for (R)-propranolol and +1.6 kcal/mol and +11.6 cal/(mol K), respectively, for (S)-propranolol at pH = 5.5. This explains why at this pH the retention time of the less-retained R enantiomer decreases with increasing temperature, while the retention time of the S enantiomer increases, causing a large increase of the separation factor when the temperature is raised from 5 to 45{degree}C. The saturation capacity of the chiral contributions depends strongly on the pH, and the retention times of both enantiomers decrease with increasing temperature at pH = 4.7. 46 refs., 6 figs., 5 tabs.

  20. 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

  1. 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…

  2. Kinetics of phase separation in polymer mixtures: A molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Singh, Awaneesh; Puri, Sanjay; Dasgupta, Chandan

    2014-06-01

    We present detailed results from a molecular dynamics (MD) simulation of phase-separation kinetics in polymer mixtures. Our MD simulations naturally incorporate hydrodynamic effects. We find that polymeric phase separation (with dynamically symmetric components) is in the same universality class as segregation of simple fluids: the degree of polymerization only slows down the segregation kinetics. For d = 2 polymeric fluids, the domain growth law is L(t) ˜ tϕ with ϕ showing a crossover from 1/3 → 1/2 → 2/3. For d = 3 polymeric fluids, we see the crossover ϕ = 1/3 → 1. Our MD simulations do not yet access the inertial hydrodynamic regime (with L ˜ t2/3) of phase separation in 3-d fluids.

  3. 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

    2015-01-01

    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.

  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. Experimental studies of flow separation and stalling on a two-dimensional airfoil at low speeds

    NASA Technical Reports Server (NTRS)

    Seetharam, H. C.; Wentz, W. H., Jr.

    1975-01-01

    Detailed measurements of flow fields associated with low-speed turbulent boundary layers were made for the 17% thick GA(W)-1 airfoil section at nominal angles of attack of 10 deg, 14 deg, and 18 deg, Reynolds number 2.2 x 10, and Mach number 0.13. The data include pressure and velocity surveys of the pre- and post-separated regions on the airfoil and the associated wake. The boundary layer characteristics including regions of separation on the airfoil are also presented.

  8. Nonaqueous battery with special separator

    SciTech Connect

    Lu, W.T.P.

    1988-04-26

    A nonaqueous secondary battery is described comprising a lithium negative electrode, a positive electrode with positive electrode active material, separator material, and electrolyte; characterized in that the separator material comprises microporous polypropylene radiation grafted with an olefinic monomer.

  9. The separation and characterization of a hydrogen getter product mixture: Part 2, measurement of product vapor pressures

    SciTech Connect

    Fircish, D.W.; Shell, T.R.

    1987-06-04

    HCPB is the acronym of an organic hydrogen getter compound used in weapon systems. When this material scavenges hydrogen by reacting with it, a number of compounds are formed, each of which is more volatile than HCPB. It is desirable to know the vapor pressure of these products in order to assess their migration potential within the weapon. In this study, individual compounds from a reacted HCPB mixture were isolated and their vapor pressures were measured. Three of the four fractions examined with a modified capacitance manometer were found to have vapor pressures under 1 mtorr; the fourth was measured at 92 +- 15 mtorr. An attempt was made to obtain boiling point data on the two liquid components of the getter mixture, but they decomposed before reaching their boiling points.

  10. 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.

  11. Comparison study of solid/liquid separation techniques for oilfield pit closures

    SciTech Connect

    Wojtanowicz, A.K.; Field, S.D.; Osterman, M.C.

    1987-07-01

    Vacuum filtration, belt-press filtration, screw-press filtration, and centrifuging techniques were evaluated in full-scale experiments for use in oilfield waste volume reduction. Centrifuging and belt-press filtration proved applicable to oilfield pit cleanups. Also, an effective chemical conditioning (coagulation and flocculation) was found for deliquoring seven types of oilfield waste slurries before separation.

  12. Study of the instabilities induced near the separator plate in atomization processes

    NASA Astrophysics Data System (ADS)

    Fuster, Daniel; Zaleski, Stephane

    2008-11-01

    This work presents current advances in the simulation of the primary atomization zone, paying a special attention to the effect of the separator plate on the flow patterns observed downstream. Gerris, a CFD Open Source code, is used to perform the simulations. The methods implemented on it combining adaptive quad/octree spatial discretisation, geometrical Volume-Of-Fluid interface representation, balanced-force continuum-surface-force surface tension formulation and height-function curvature estimation, have allowed us to carry out accurate simulations near the separator plate. The inclusion of the separator plate in the analysis have been shown to have a capital importance on the instabilities generated just after it. The influence of some operational parameters like the momentum ratio, the gas and liquid Reynolds numbers based on the thickness of the boundary layer, the density and viscosity ratios or the thickness and angle of the separator plate are investigated. The analysis of these phenomena is aimed at shedding some new insight into the physical mechanisms controlling atomization processes and to provide better basis for future theoretical analysis.

  13. 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,…

  14. A Case Study of Choice in Education: Separate Schools in Ontario.

    ERIC Educational Resources Information Center

    Lawton, Stephen B.

    Both Protestant and Catholic residents of Ontario's school districts have historically had the right to establish separate public elementary school boards and schools, and to levy taxes to support those schools, under most conditions. Only recently have all major political parties in Ontario agreed to funding Catholic public secondary schools…

  15. 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.

  16. 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

  17. 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.

  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. Numerical study of the phase separation in binary lipid membrane containing protein inclusions under stationary shear flow.

    PubMed

    Chen, Xiao-Bo; Shi, Hui-Ji; Niu, Li-Sha

    2009-03-26

    The phase separation of lipids is believed to be responsible for the formation of lipid rafts in biological cell membrane. In the present work, a continuum model and a particle model are constructed to study the phase separation in binary lipid membrane containing inclusions under stationary shear flow. In each model, employing the cell dynamical system (CDS) approach, the kinetic equations of the confusion-advection process are numerically solved. Snapshot figures of the phase morphology are performed to intuitively display such phase evolving process. Considering the effects from both the inclusions and the shear flow, the time growth law of the characteristic domain size is discussed.

  20. Renormalization-Group Theory Study of Superfluidity and Phase Separation of Helium Mixtures Immersed in Jungle-Gym Aerogel

    NASA Astrophysics Data System (ADS)

    Lopatnikova, Anna; Berker, A. Nihat

    1997-03-01

    Superfluidity and phase separation in ^3He-^4He mixtures immersed in jungle-gym (non-random) aerogel are studied by renormalization-group theory.(Phys. Rev. B, in press (1996)) Phase diagrams are calculated for a variety of aerogel concentrations. Superfluidity at very low ^4He concentrations and a depressed tricritical temperature are found at the onset of superfluidity. A superfluid-superfluid phase separation, terminating at an isolated critical point, is found entirely within the superfluid phase. These phenomena, and trends with respect to aerogel concentration, are explained by the connectivity and tenuousness of jungle-gym aerogel.

  1. Renormalization-group study of superfluidity and phase separation of helium mixtures immersed in a nonrandom aerogel

    NASA Astrophysics Data System (ADS)

    Lopatnikova, Anna; Nihat Berker, A.

    1997-02-01

    Superfluidity and phase separation in 3-4He mixtures immersed in a jungle-gym (nonrandom) aerogel are studied by renormalization-group theory. Phase diagrams are calculated for a variety of aerogel concentrations. Superfluidity at very low 4He concentrations and a depressed tricritical temperature are found at the onset of superfluidity. A superfluid-superfluid phase separation, terminating at an isolated critical point, is found entirely within the superfluid phase. These phenomena and trends with respect to aerogel concentration are explained by the connectivity and tenuousness of a jungle-gym aerogel.

  2. 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…

  3. 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.

  4. Abort separation study of a shuttle orbiter and external tank at hypersonic speeds

    NASA Technical Reports Server (NTRS)

    Bernot, P. T.

    1975-01-01

    The effects of several parameters on the relative motions of a space shuttle orbiter design and its external tank were determined during staging for the return-to-launch-site abort mode. The parameters included angle of attack, dynamic pressure, flight-path angle, pitch rate, elevon effectiveness and the use of thrust applied to the tank. The relative positions of each component were determined by a separation trajectory computer program which incorporated data obtained in wind-tunnel tests with the orbiter and tank in proximity. These tests were conducted at Mach 10.3 in a continuous-flow hypersonic tunnel. All separation cases were initiated at a constant Mach number of 10 with an assumed sideslip angle of 0 deg.

  5. Attachment Anxiety, Verbal Immediacy, and Blood Pressure: Results from a Laboratory-Analogue Study Following Marital Separation

    PubMed Central

    Lee, Lauren A.; Sbarra, David A.; Mason, Ashley E.; Law, Rita W.

    2011-01-01

    Marital separation and divorce increase risk for all-cause morbidity and mortality. Using a laboratory analogue paradigm, the present study examined attachment anxiety, language use, and blood pressure (BP) reactivity among 119 (n = 43 men, 76 women) recently separated adults who were asked to mentally reflect on their relationship history and separation experience. We created a language use composite of verbal immediacy from participants’ stream-of-consciousness recordings about their separation experience as a behavioral index of attachment-related hyperactivation. Verbal immediacy moderated the association between attachment anxiety and BP at the beginning of a divorce-specific activation task. Participants reporting high attachment anxiety who discussed their separation in a first-person, present-oriented and highly engaged manner evidenced the highest levels of BP at the start of the divorce-specific task. Results provide a deeper understanding of the association between marital dissolution and health and suggest that verbal immediacy may be a useful behavioral index of hyperactivating coping strategies. PMID:21647240

  6. Blind source separation methods applied to synthesized polysomnographic recordings: a comparative study

    PubMed Central

    Kachenoura, Amar; Albera, Laurent; Senhadji, Lotfi

    2007-01-01

    Blind Source Separation (BSS) problems, under the assumption of static mixture, were extensively explored from the theoretical point of view. Powerful algorithms are now at hand to deal with many concrete BSS applications. Nevertheless, the performances of BSS methods, for a given biomedical application, are rarely investigated. The aim of this paper is to perform quantitative comparisons between various well-known BSS techniques. To do so, synthetic data, reproducing real polysomnographic recordings, are considered. PMID:18002843

  7. Experimental studies using a low-energy RI beam separator at CNS

    NASA Astrophysics Data System (ADS)

    Teranishi, T.; Kubono, S.; Shimoura, S.; Notani, M.; Yanagisawa, Y.; Michimasa, S.; Ue, K.; Iwasaki, H.; Kurokawa, M.; Satou, Y.; Morikawa, T.; Saito, A.; Baba, H.; Lee, J. H.; Lee, C. S.; Fülöp, Zs.; Kato, S.

    2003-05-01

    Radioactive-ion (RI) beams of 10C, 14O, 12N and 11C with energies low 10 A MeV were produced by using a low-energy in-flight RI beam separator newly constructed by CNS, University of Tokyo. Using the 12N and 11C beams, some resonance states were identified in the proton elastic scattering 12N+p and 11C+p, respectively.

  8. 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.

  9. 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.

  10. Experimental Studies of Flow Separation of the NACA 2412 Airfoil at Low Speeds

    NASA Technical Reports Server (NTRS)

    Seetharam, H. C.; Rodgers, E. J.; Wentz, W. H., Jr.

    1997-01-01

    Wind tunnel tests have been conducted on an NACA 2412 airfoil section at Reynolds number of 2.2 x 10(exp 6) and Mach number of 0.13. Detailed measurements of flow fields associated with turbulent boundary layers have been obtained at angles of attack of 12.4 degrees, 14.4 degrees, and 16.4 degrees. Pre- and post-separated velocity and pressure survey results over the airfoil and in the associated wake are presented. Extensive force, pressure, tuft survey, hot-film survey, local skin friction, and boundary layer data are also included. Pressure distributions and separation point locations show good agreement with theory for the two layer angles of attack. Boundary layer displacement thickness, momentum thickness, and shape factor agree well with theory up to the point of separation. There is considerable disparity between extent of flow reversal in the wake as measured by pressure and hot-film probes. The difference is attributed to the intermittent nature of the flow reversal.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. Report of the Energy Research Advisory Board study group on advanced isotope separation

    SciTech Connect

    Not Available

    1980-11-01

    The Panel reviewed Advanced Isotope Separation (AIS) technology and Advanced Gas Centrifuge (AGC) programs in the context of potential needs and costs for uranium enrichment. The benefit of a successful AIS or AGC program would be a substantial reduction in enrichment costs below those of current centrifuge plants or below the power cost alone for gaseous diffusion plants. This report attempts to provide firm guidance for the next 2 to 3 years, at which time a further evaluation should guide decisions in regard to enrichment supply and development choices. On the basis of our perception of the long-term economic benefits of a successful AIS development, we support the continued pursuit of this option. In the interim, major requirements for enrichment must be satisfied. We assume that DOE will develop a firm funding plan for gaseous diffusion operations and power contracting to assure that the necessary supply of power will be available to meet the separative work commitments of the US enrichment enterprise. We recommend that the AIS program office further identify the key technical uncertainties of the various programs, thereby establishing the basis for near-term R and D leading to a decision whether and when to proceed with full-scale development. We believe that a stronger atomic vapor laser isotope separation (AVLIS) program would result from a consolidation of the Lawrence Livermore National Laboratory (LLNL) and Jersey Nuclear Avco Isotopes (JNAI) teams, leading to a more competitive AVLIS process. Hence, we recommend that DOE attempt to negotiate with JNAI to form a single, integrated, government-funded AVLIS program with appropriate elements of LLNL, JNAI and UCC-ND. We further recommend that JNAI be designated as lead laboratory in this program. We recommend that the DOE: continue with the first 2.2 million SWU increment of the gas centrifuge program, and continue the Advanced Gas Centrifuge development program, with high priority.

  18. Studies of high-field sections of a muon helical cooling channel with coil separation

    SciTech Connect

    Lopes, M.L.; Kashikhin, V.S.; Yonehara, K.; Yu, M.; Zlobin, A.V.; /Fermilab

    2011-03-01

    The Helical Cooling Channel (HCC) was proposed for 6D cooling of muon beams required for muon collider and some other applications. HCC uses a continuous absorber inside superconducting magnets which produce solenoidal field superimposed with transverse helical dipole and helical gradient fields. HCC is usually divided into several sections each with progressively stronger fields, smaller aperture and shorter helix period to achieve the optimal muon cooling rate. This paper presents the design issues of the high field section of HCC with coil separation. The effect of coil spacing on the longitudinal and transverse field components is presented and its impact on the muon cooling discussed. The paper also describes methods for field corrections and their practical limits. The magnetic performance of the helical solenoid with coil separation was discussed in this work. The separation could be done in three different ways and the performances could be very different which is important and should be carefully described during the beam cooling simulations. The design that is currently being considered is the one that has the poorest magnetic performance because it presents ripples in all three components, in particular in the helical gradient which could be quite large. Moreover, the average gradient could be off, which could affect the cooling performance. This work summarized methods to tune the gradient regarding the average value and the ripple. The coil longitudinal thickness and the helix period can be used to tune G. Thinner coils tend to reduce the ripples and also bring G to its target value. However, this technique reduces dramatically the operational margin. Wider coils can also reduce the ripple (not as much as thinner coils) and also tune the gradient to its target value. Longer helix periods reduce ripple and correct the gradient to the target value.

  19. Separation of Americium from Europium using Camphor-BisTriazinyl Pyridine: A Fundamental Study

    DOE PAGESBeta

    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.

  20. 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.

  1. 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.

  2. Removal of malaria-infected red blood cells using magnetic cell separators: A computational study.

    PubMed

    Kim, Jeongho; Massoudi, Mehrdad; Antaki, James F; Gandini, Alberto

    2012-02-15

    High gradient magnetic field separators have been widely used in a variety of biological applications. Recently, the use of magnetic separators to remove malaria-infected red blood cells (pRBCs) from blood circulation in patients with severe malaria has been proposed in a dialysis-like treatment. The capture efficiency of this process depends on many interrelated design variables and constraints such as magnetic pole array pitch, chamber height, and flow rate. In this paper, we model the malaria-infected RBCs (pRBCs) as paramagnetic particles suspended in a Newtonian fluid. Trajectories of the infected cells are numerically calculated inside a micro-channel exposed to a periodic magnetic field gradient. First-order stiff ordinary differential equations (ODEs) governing the trajectory of particles under periodic magnetic fields due to an array of wires are solved numerically using the 1(st) -5(th) order adaptive step Runge-Kutta solver. The numerical experiments show that in order to achieve a capture efficiency of 99% for the pRBCs it is required to have a longer length than 80 mm; this implies that in principle, using optimization techniques the length could be adjusted, i.e., shortened to achieve 99% capture efficiency of the pRBCs. PMID:22345827

  3. Removal of malaria-infected red blood cells using magnetic cell separators: A computational study

    PubMed Central

    Kim, Jeongho; Massoudi, Mehrdad; Antaki, James F.; Gandini, Alberto

    2012-01-01

    High gradient magnetic field separators have been widely used in a variety of biological applications. Recently, the use of magnetic separators to remove malaria-infected red blood cells (pRBCs) from blood circulation in patients with severe malaria has been proposed in a dialysis-like treatment. The capture efficiency of this process depends on many interrelated design variables and constraints such as magnetic pole array pitch, chamber height, and flow rate. In this paper, we model the malaria-infected RBCs (pRBCs) as paramagnetic particles suspended in a Newtonian fluid. Trajectories of the infected cells are numerically calculated inside a micro-channel exposed to a periodic magnetic field gradient. First-order stiff ordinary differential equations (ODEs) governing the trajectory of particles under periodic magnetic fields due to an array of wires are solved numerically using the 1st –5th order adaptive step Runge-Kutta solver. The numerical experiments show that in order to achieve a capture efficiency of 99% for the pRBCs it is required to have a longer length than 80 mm; this implies that in principle, using optimization techniques the length could be adjusted, i.e., shortened to achieve 99% capture efficiency of the pRBCs. PMID:22345827

  4. 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.

  5. PHASE SEPARATION IN PM 2000 FE-BASE ODS ALLOY: EXPERIMENTAL STUDY AT THE ATOMIC LEVEL

    SciTech Connect

    Capdevila, C.; Miller, Michael K; Russell, Kaye F; Chao, J.; Gonzalez-Carrasco, J. L.

    2008-01-01

    The coarsening of the three-dimensional microstructure resulting from phase separation during ageing at 748 K of a Fe-based PM 2000{trademark} oxide dispersion strengthened (ODS) steel has been investigated by atom probe tomography and hardness measurements. Phase separation resulted in the formation of isolated particles of the chromium-enriched {alpha}{prime} phase. The aluminum and titanium were found to preferential partition to the iron-rich {alpha} phase. The partitioning of aluminum is consistent with theoretical calculations. The change in the scale of the chromium-enriched {alpha}{prime} phase was found to fit a power law with a time exponent of 0.32 in accordance with that predicted by the classical Lifshitz, Slyozov and Wagner (LSW) theory. The solute concentrations of the coexisting {alpha} and {alpha}{prime} phases were estimated from concentration frequency distributions with the Langer-Bar-on-Miller (LBM) method and proximity histograms. The hardness was linearly related to the chromium content of the {alpha}{prime} phase.

  6. 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.

  7. 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).

  8. 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.

  9. 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). PMID:24556171

  10. Preparation and characterization of TiO2 anode film with spinodal phase separation structure in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Guli, Mina; Yao, Jianxi; Zhao, Jingyong; Rao, Wangping; Xiao, Li; Tian, Hongxin

    2013-10-01

    Low electronic transmission efficiency and high charge recombination are the existing problems of photoanode film in traditional dye sensitized solar cells (DSSCs). This paper put forward the photoanode TiO2 films with spinodal phase separation structure (SPSS) and continuous TiO2 skeleton which were triggered by the photopolymerization of organic monomers in a photomonomer-inorganic precursor system. The photoanode TiO2 films fabricated by different precursor solution compositions and different coating layers were characterized mainly by scanning electron microscopy (SEM), photocatalysis and photoelectric performance test. The results indicated that, the as-prepared TiO2 anode film with seven coating layers and heat treated at 500 °C showed higher photoelectric conversion efficiency at about 2% than that of other samples with less coating layers and lower heat treatment temperature. The film also showed excellent photocatalytic activity by using methylene blue (MB) dye as a model organic substrate under fluorescent lamp irradiation. It is suggested that the film with SPSS structure has the potential to improve the electronic transmission efficiency and reduce the carrier recombination due to its particular structure, higher surface area, and lack of bottleneck in electronic transmission. It is worth noting that the SPSS structure provides new ideas to develop new photoanode films and further improve the photoelectric conversion performance of the DSSC in future.

  11. 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).

  12. 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). PMID:27466152

  13. Study of the enantiomeric separation of oxfendazole and cetirizine using subcritical fluid chromatography on an amylose-based column.

    PubMed

    Toribio, L; del Nozal, M J; Bernal, J L; Cristofol, C; Alonso, C

    2006-07-21

    The enantiomeric separation of cetirizine and oxfendazole on a Chiralpak AD column using subcritical fluid chromatography has been studied in this work. The enantioseparation of cetirizine was only possible when 2-propanol was used as a modifier, obtaining better results in presence of the additives triethylamine (TEA) and trifluoroacetic acid (TFAA). On the contrary, 2-propanol provided the lowest enantioresolutions for oxfendazole, in this case the best results in terms of high resolution and short analysis time were obtained with ethanol. The study of the temperature effect revealed that in the case of cetirizine using 2-propanol, and oxfendazole using methanol, the separation was enthalpy-driven and the isoelution temperature was above the working range. Using ethanol or 2-propanol, the results showed that the oxfendazole enantioseparation was entropically driven and the isoelution temperatures were below the range studied.

  14. 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.

  15. EDTA separation and recombination of epithelium and connective tissue of human oral mucosa. Studies of tissue transplants in nude mice.

    PubMed

    Holmstrup, P; Dabelsteen, E; Harder, F

    1985-01-01

    A possible epithelial-mesenchymal interaction in determining epithelial histologic features of human oral mucosa was examined. The study comprised 74 biopsies of normal buccal mucosa and 54 biopsies of normal palatal mucosa. Epithelium was separated from connective tissue by the use of 1 mM ethylenediamine tetraacetate dihydrate. Self-recombined and cross-recombined epithelial and connective tissues and connective tissue sheets alone were transplanted to subcutaneous sites of nude mice. Histologic examination of cross-recombined palatal epithelium/buccal connective tissue transplants showed a change in keratinization pattern but no major change in number of epithelial cell layers as the result of connective tissue influence. Transplanted sheets of connective tissue after growth for 14 days showed that complete separation of biopsies from buccal mucosa had been obtained. However, palatal mucosa had been incompletely separated as evidenced by re-epithelialization of most of the connective tissue transplants. The consequences of the incomplete palatal epithelium-connective tissue separation are discussed.

  16. 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.

  17. Study on the performance improvement of the high temperature superconducting coil with several separated coils at the edges

    NASA Astrophysics Data System (ADS)

    Ishiguri, S.; Oka, T.; Fukui, S.; Ogawa, J.; Sato, T.

    2008-09-01

    In designing high temperature superconducting (HTS) coils, it is important to secure large magnetic fields and stored energy using shorter tape length. Thus, it is necessary to improve the transport current performance of the coils. The critical current and n-value of an HTS tape depend on magnetic fields and flux angles under constant temperature. Considering these dependencies, we established a model to analyze coil critical current. This model clarifies that relatively large electric fields are generated at the coil edges. This adversely affects the transport current performance. In this study, the coil edge is separated into several coils, keeping the total tape length constant. This increases the coil critical current, stored energy, central magnetic field, and also the coil volume, which contains vacancies created by the separation. To estimate coil performance, we calculated the stored energy density, whose denominator is the increased coil volume. This stored energy density reaches its maximum value when the number of the separated coils is eight. At this optimum separation, the central magnetic field increases by 13%, and the stored energy improves by 43%, compared to a rectangular coil wound with the same tape length.

  18. Property-close source separation of hazardous waste and waste electrical and electronic equipment - A Swedish case study

    SciTech Connect

    Bernstad, Anna; Cour Jansen, Jes la; Aspegren, Henrik

    2011-03-15

    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.

  19. 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.

  20. Deformability-based red blood cell separation in deterministic lateral displacement devices—A simulation study

    PubMed Central

    Krüger, Timm

    2014-01-01

    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. PMID:25584112

  1. 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.

  2. Experimental and analytical study of a conically diffused flow with a nearly separated boundary layer

    NASA Technical Reports Server (NTRS)

    Boldman, D. R.; Neumann, H. E.

    1973-01-01

    Turbulence measurements were obtained in the nearly separated flow in a 13 deg total angle of divergence conical diffuser coupled to a constant area tailpipe. Air at 207 newtons per square centimeter and 308 K provided an inlet velocity of about 51 meters per second at an inlet unit Reynolds number of 63.7 million per meter. Very high longitudinal turbulence intensities accompanied the diffusion process with peak values approaching 40 percent when normalized by the local centerline velocity. Predictions of the pressure recovery coefficient using a mixing length concept were good in the early stages of diffusion. In the latter stages of diffusion satisfactory predictions of the pressure recovery were obtained with an empirical method.

  3. 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.

  4. 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.

  5. 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.

  6. Rapid separation and characterization of active flavonolignans of Silybum marianum by ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry.

    PubMed

    Wang, Kuiwu; Zhang, Hong; Shen, Lianqing; Du, Qizhen; Li, Jianrong

    2010-12-01

    Ultra-performance liquid chromatography (UPLC) interfaced with the electrospray ionization (ESI) tandem mass spectrometer (MS(n)) was developed for the simultaneous determination of silychristins A (1) and B (2), silydianin (3), silybins A (4) and B (5), and isosilybins A (6) and B (7), major bioactive flavonolignans in silymarin, a herbal remedy derived from the milk thistle Silybum marianum. In this study, the seven major active flavonolignans including the diastereomers 1/2, 4/5, and 6/7 were completely separated using UPLC with an ACQUITY UPLC C(18) column and a MeOH/water/formic acid mobile phase system. The collision-induced dissociation (CID) MS(n) spectra of these flavonolignans were studied systematically using ESI-MS. The results with the present methodology show that UPLC-MS(n) can be useful for general screening of active natural products from plant extracts and for the specific quality control of silymarin.

  7. 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)

  8. 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.

  9. Preparation and characterization of gelatin from collagen biomass obtained through a pH-shifting process of mechanically separated turkey meat.

    PubMed

    Du, L; Keplová, L; Khiari, Z; Betti, M

    2014-04-01

    Gelatins were extracted from mechanically separated turkey meat following 2 different approaches. The first method was based on a 2-stage batch extraction at 50 and 60°C, respectively, whereas the second method consisted of recovering gelatin from a collagen biomass obtained during a pH-shifting process. The yield of gelatin produced by the latter method was twice that obtained by the former method (13.51 and 6.36%, respectively). The chemical composition, as well as the rheological and the functional properties, of all extracted gelatins were evaluated. Gelatin recovered from the collagen biomass had higher molecular weight components and significantly greater (P < 0.05) bloom value (353.2 g) compared with thermally extracted gelatins. However, gelatin extracted at 60°C possessed higher (P < 0.05) foaming properties, as well as better emulsifying activity, than gelatin extracted from the 50°C treatment and the collagen biomass. The present study revealed that high-quality gelatins can be prepared from mechanically separated turkey meat through precipitation and thermal solubilization of collagen biomass obtained during a pH-shifting process. PMID:24706977

  10. 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

  11. The Preparation and Characterization of INTEC Phase 2b Composition Variation Study Glasses

    SciTech Connect

    B. A. Staples; B. A. Scholes; L. L. Torres; C. A. Musick; B. R. Boyle; D. K. Peeler; J. D. Vienna

    2000-02-01

    The second phase of the composition variation study (CVS) for the development of glass compositions to immobilize Idaho Nuclear Technology and Engineering Center (INTEC) high level wastes (HLW) is complete. This phase of the CVS addressed waste composition of high activity waste fractions (HAW) from the initial separations flowsheet. Updated estimates if INTEC calcined HLW compositions and of high activity waste fractions proposed to be separated from dissolved calcine were used as the waste component for this CVS phase. These wastes are of particular interest because high aluminum, calcium, zirconium, fluorine, potassium, and low iron and sodium content places them outside the vitrification experience in the Department of Energy complex. Because of the presence of calcium and fluorine, two major zirconia calcine components not addressed in Phase I, a series of scooping tests, designated Phase 2a, were performed. The results of these tests provided information on the effects of calcium and fluoride solubility and their impacts on product properties and composition boundary information for Phase 2b. Details and results of Phase 2a are reported separately. Through application of statistical techniques and the results of Phase 2a, a test matrix was defined for Phase 2b of the CVS. From this matrix, formulations were systematically selected for preparation and characterization with respect to visual and optical homogeneity, viscosity as a function of melt temperature, liquidus temperature (TL), and leaching properties based on response to the product consistency test. The results of preparing and characterizing the Phase 2b glasses are presented in this document. Based on the results, several formulations investigated have suitable properties for further development. A full analysis of the composition-product characteristic relationship of glasses being developed for immobilizing INTEC wastes will be performed at the completion of composition-property relationship

  12. Hydrochloride salt co-crystals: preparation, characterization and physicochemical studies.

    PubMed

    Parmar, Vijaykumar K; Shah, Shailesh A

    2013-01-01

    Co-crystallization approach for modification of physicochemical properties of hydrochloride salt is presented. The objective of this investigation was to study the effect of co-crystallization with different co-crystal formers on physicochemical properties of fluoxetine hydrochloride (FH). FH was screened for co-crystallization with a series of carboxylic acid co-formers by slow evaporation method. Photomicrographs and melting points of crystalline phases were determined. The co-crystals were characterized by FTIR, DSC and PXRD methods. Solubility of co-crystals was determined in water and buffer solutions. Powder and intrinsic dissolution profiles were assessed for co-crystals. Physical mixtures of drug and co-formers were used for comparisons at characterizations and physicochemical properties evaluation stages. Four co-crystals of FH viz. Fluoxetine hydrochloride-maleic acid (FH-MA), Fluoxetine hydrochloride-glutaric acid (FH-GA), Fluoxetine hydrochloride-L-tartaric acid (FH-LTA) and Fluoxetine hydrochloride-DL-tartaric acid (FH-DLTA) were obtained from screening experiments. Physical characterization showed that they have unique crystal morphology, thermal, spectroscopic and X-ray diffraction properties. Solubility and dissolution studies showed that Fluoxetine hydrochloride-maleic acid co-crystal possess high aqueous solubility in distilled water, pH 4.6, 7.0 buffer solutions and dissolution rate in distilled water than that of pure drug. Co-crystal formation approach can be used for ionic API to tailor its physical properties. PMID:22686294

  13. Hydrochloride salt co-crystals: preparation, characterization and physicochemical studies.

    PubMed

    Parmar, Vijaykumar K; Shah, Shailesh A

    2013-01-01

    Co-crystallization approach for modification of physicochemical properties of hydrochloride salt is presented. The objective of this investigation was to study the effect of co-crystallization with different co-crystal formers on physicochemical properties of fluoxetine hydrochloride (FH). FH was screened for co-crystallization with a series of carboxylic acid co-formers by slow evaporation method. Photomicrographs and melting points of crystalline phases were determined. The co-crystals were characterized by FTIR, DSC and PXRD methods. Solubility of co-crystals was determined in water and buffer solutions. Powder and intrinsic dissolution profiles were assessed for co-crystals. Physical mixtures of drug and co-formers were used for comparisons at characterizations and physicochemical properties evaluation stages. Four co-crystals of FH viz. Fluoxetine hydrochloride-maleic acid (FH-MA), Fluoxetine hydrochloride-glutaric acid (FH-GA), Fluoxetine hydrochloride-L-tartaric acid (FH-LTA) and Fluoxetine hydrochloride-DL-tartaric acid (FH-DLTA) were obtained from screening experiments. Physical characterization showed that they have unique crystal morphology, thermal, spectroscopic and X-ray diffraction properties. Solubility and dissolution studies showed that Fluoxetine hydrochloride-maleic acid co-crystal possess high aqueous solubility in distilled water, pH 4.6, 7.0 buffer solutions and dissolution rate in distilled water than that of pure drug. Co-crystal formation approach can be used for ionic API to tailor its physical properties.

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. The study of exotic N approx equal 82 nuclei using the Daresbury recoil mass separator

    SciTech Connect

    McNeill, J.H.; Chishti, A.A.; Gelletly, W.; Hotchkis, M.A.C.; Varley, B.J.; Blomqvist, J.; Daly, P.J.; Piiparinen, M.; Woods, P.J.; Manchester Univ. . Schuster Lab.; Manne Siegbahn Inst.; Purdue Univ., Lafayette, IN . Dept. of Chemistry; Jyvaeskylae Univ. . Dept. of Physics; Edinburgh Univ. . Dept. of Physics)

    1989-01-01

    Experiments using the Daresbury Recoil Mass Separator have identified microsecond isomers in the exotic N {equals} 82, 83 nuclei {sup 153}Yb, {sup 153}Lu, {sup 154}Hf, and have established their decay schemes. The results for {sup 153}Lu and {sup 154}Hf, together with those for lighter N {equals} 82 isotones, provide an outstanding illustration of the dependence of E2 transition rates between J{sup n} states on the subshell occupation, and demonstrate that half-filling of the {pi}h{sub 11/2} subshell in the N {equals} 82 series occurs just below Z {equals} 71 {sup 153}Lu. The result of the isomer in the even-odd N {equals} 83 nucleus {sup 153}Yb shows that the isomerism is due to a low-energy E2 transition rather than an E3 transition as in lighter N {equals} 83 even-odd isotones, which is another consequence of the {pi}h{sub 11/2} subshell being about half-filled. Furthermore, the long-lived isomer observed in the odd-odd N {equals} 83 nucleus {sup 154}Lu also reflects that the {pi}h{sub 11/2} subshell is close to being half-filled. 23 refs., 12 figs., 4 tabs.

  20. A Pilot Study of an Acceptance-Based Separated Family Treatment for Adolescent Anorexia Nervosa

    PubMed Central

    Merwin, Rhonda M.; Zucker, Nancy L.; Timko, C. Alix

    2016-01-01

    The treatment of adolescent anorexia nervosa (AN) has improved significantly with the increased emphasis on family-based intervention. Yet despite advances, a substantial number of adolescents do not respond optimally to existing treatment models and thus there is a need for treatment alternatives that address barriers to recovery. We developed and piloted an acceptance-based separated family treatment (ASFT) with 6 adolescents with AN or subthreshold AN (eating disorder not otherwise specified, with the primary symptoms of restriction and severe weight loss). Treatment acceptability was adequate. Overall, parents rated the treatment as credible and expected improvement in their child's condition. Five of the 6 adolescents treated with ASFT restored weight to their ideal body mass index as indicated by age, height, and sex and determined by individual growth charts. Many demonstrated improved psychological health and adaptive functioning. There was evidence of broad effects, with parents reporting decreased anxiety and caregiver burden. ASFT holds promise as a treatment option for AN. The efficacy of this therapeutic approach should be tested in larger trials and compared to current family-based interventions to determine unique effects. PMID:27307691

  1. 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.

  2. 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. PMID:25981986

  3. 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.

  4. An experimental study of separation control on ultra-highly-loaded low pressure turbine blade by surface roughness

    NASA Astrophysics Data System (ADS)

    Sun, Shuang; Lei, Zhijun; Lu, Xingen; Zhao, Shengfeng; Zhu, Junqiang

    2015-06-01

    An experimental study is conducted to improve an aft-loaded ultra-high-lift low pressure turbine (LPT) blade at low Reynolds number (Re) in steady state. The objective is to investigate the effect of blade roughness on the performance of LPT blade. The roughness is used as a passive flow control method which is to reduce total pressure loss and expand LPT operating margin. The experiment is performed on a low-speed cascade facility. 3 roughness heights and 3 deposit positions are investigated in the experiment which forms a large test matrix. A three-hole probe is used to detect flow aerodynamic performance and a hotwire probe is used to detect the characteristic of suction boundary layer. Regional roughness can suppress separation loss and bring fairly low turbulent dissipation loss. Detailed surveys near the blade surface shows that the loss reduction is due to the disappearance of separation bubble from the early transition onset.

  5. 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.

  6. Design and studies on supramolecular ferrocene-porphyrin-fullerene constructs for generating long-lived charge separated states.

    PubMed

    D'Souza, Francis; Chitta, Raghu; Gadde, Suresh; Islam, D-M Shafiqul; Schumacher, Amy L; Zandler, Melvin E; Araki, Yasuyuki; Ito, Osamu

    2006-12-21

    Supramolecular ferrocene-porphyrin-fullerene constructs, in which covalently linked ferrocene-porphyrin-crown ether compounds were self-assembled with alkylammonium cation functionalized fullerenes, have been designed to achieve stepwise electron transfer and hole shift to generate long-lived charge separated states. The adopted crown ether-alkylammonium cation binding strategy resulted in stable conjugates as revealed by computational studies performed by the DFT B3LYP/3-21G(*) method in addition to the binding constants obtained from fluorescence quenching studies. The free-energy changes for charge-separation and charge-recombination were varied by the choice of different metal ions in the porphyrin cavity. Free-energy calculations suggested that the light-induced electron-transfer processes from the singlet excited state of porphyrins to be exothermic in all of the investigated supramolecular dyads and triads. Photoinduced charge-separation and charge-recombination processes have been confirmed by the combination of the time-resolved fluorescence and nanosecond transient absorption spectral measurements. In case of the triads, the charge-recombination processes of the radical anion of the fullerene moiety take place in two steps, viz., a direct charge recombination from the porphyrin cation radical and a slower step involving distant charge recombination from the ferrocene cation moiety. The rates of charge recombination for the second route were found to be an order of magnitude slower than the former route, thus fulfilling the condition for charge migration to generate long-lived charge-separated states in supramolecular systems.

  7. Going beyond 20 μm-sized channels for studying red blood cell phase separation in microfluidic bifurcations.

    PubMed

    Roman, Sophie; Merlo, Adlan; Duru, Paul; Risso, Frédéric; Lorthois, Sylvie

    2016-05-01

    Despite the development of microfluidics, experimental challenges are considerable for achieving a quantitative study of phase separation, i.e., the non-proportional distribution of Red Blood Cells (RBCs) and suspending fluid, in microfluidic bifurcations with channels smaller than 20 μm. Yet, a basic understanding of phase separation in such small vessels is needed for understanding the coupling between microvascular network architecture and dynamics at larger scale. Here, we present the experimental methodologies and measurement techniques developed for that purpose for RBC concentrations (tube hematocrits) ranging between 2% and 20%. The maximal RBC velocity profile is directly measured by a temporal cross-correlation technique which enables to capture the RBC slip velocity at walls with high resolution, highlighting two different regimes (flat and more blunted ones) as a function of RBC confinement. The tube hematocrit is independently measured by a photometric technique. The RBC and suspending fluid flow rates are then deduced assuming the velocity profile of a Newtonian fluid with no slip at walls for the latter. The accuracy of this combination of techniques is demonstrated by comparison with reference measurements and verification of RBC and suspending fluid mass conservation at individual bifurcations. The present methodologies are much more accurate, with less than 15% relative errors, than the ones used in previous in vivo experiments. Their potential for studying steady state phase separation is demonstrated, highlighting an unexpected decrease of phase separation with increasing hematocrit in symmetrical, but not asymmetrical, bifurcations and providing new reference data in regimes where in vitro results were previously lacking.

  8. Going beyond 20 μm-sized channels for studying red blood cell phase separation in microfluidic bifurcations.

    PubMed

    Roman, Sophie; Merlo, Adlan; Duru, Paul; Risso, Frédéric; Lorthois, Sylvie

    2016-05-01

    Despite the development of microfluidics, experimental challenges are considerable for achieving a quantitative study of phase separation, i.e., the non-proportional distribution of Red Blood Cells (RBCs) and suspending fluid, in microfluidic bifurcations with channels smaller than 20 μm. Yet, a basic understanding of phase separation in such small vessels is needed for understanding the coupling between microvascular network architecture and dynamics at larger scale. Here, we present the experimental methodologies and measurement techniques developed for that purpose for RBC concentrations (tube hematocrits) ranging between 2% and 20%. The maximal RBC velocity profile is directly measured by a temporal cross-correlation technique which enables to capture the RBC slip velocity at walls with high resolution, highlighting two different regimes (flat and more blunted ones) as a function of RBC confinement. The tube hematocrit is independently measured by a photometric technique. The RBC and suspending fluid flow rates are then deduced assuming the velocity profile of a Newtonian fluid with no slip at walls for the latter. The accuracy of this combination of techniques is demonstrated by comparison with reference measurements and verification of RBC and suspending fluid mass conservation at individual bifurcations. The present methodologies are much more accurate, with less than 15% relative errors, than the ones used in previous in vivo experiments. Their potential for studying steady state phase separation is demonstrated, highlighting an unexpected decrease of phase separation with increasing hematocrit in symmetrical, but not asymmetrical, bifurcations and providing new reference data in regimes where in vitro results were previously lacking. PMID:27190568

  9. Char separator

    DOEpatents

    Matthews, Francis T.

    1979-01-01

    Particulates removed from the flue gases produced in a fluidized-bed furnace are separated into high-and low-density portions. The low-density portion is predominantly char, and it is returned to the furnace or burned in a separate carbon burnup cell. The high-density portion, which is predominantly limestone products and ash, is discarded or reprocessed. According to another version, the material drained from the bed is separated, the resulting high-and low-density portions being treated in a manner similar to that in which the flue-gas particulates are treated.

  10. CENTRIFUGAL SEPARATORS

    DOEpatents

    Skarstrom, C.

    1959-03-10

    A centrifugal separator is described for separating gaseous mixtures where the temperature gradients both longitudinally and radially of the centrifuge may be controlled effectively to produce a maximum separation of the process gases flowing through. Tbe invention provides for the balancing of increases and decreases in temperature in various zones of the centrifuge chamber as the result of compression and expansions respectively, of process gases and may be employed effectively both to neutralize harmful temperature gradients and to utilize beneficial temperaturc gradients within the centrifuge.

  11. Bacterial adherence to separated modular components in joint prosthesis: a clinical study.

    PubMed

    Gómez-Barrena, Enrique; Esteban, Jaime; Medel, Francisco; Molina-Manso, Diana; Ortiz-Pérez, Alberto; Cordero-Ampuero, Jose; Puértolas, José A

    2012-10-01

    Bacterial adherence on total joint replacement implants may lead to biofilm formation and implant-related osteoarticular infection. It is unclear if different biomaterials in the prosthetic components are more prone to facilitate this bacterial adherence, although ultrahigh molecular weight polyethylene (UHMWPE) component exchange in modular systems has been clinically utilized in the early management of these infections. To clarify if the amount of clinically adhered microorganisms was related to the material or the component, we investigated retrieved implants from infected joint replacements. Thirty-two patients were revised after confirmed implant-related infection through positive cultures. Eighty-seven total joint components (hip and knee) were obtained and separately sonicated following a previously published protocol. Cultures were quantified, and detected colony forming units (CFU) were adjusted according to the component surface and compared based on the component material and location. Variable adherence of bacteria to chrome cobalt alloys, UHMWPE, hydroxyapatite coated components, and titanium alloys. The commonest isolated organisms were Staphylococcus epidermidis (23 of 87 components) and Staphylococcus aureus (10 of 87). Twelve components did not show any microorganism adhered despite location in an infected joint, with positive cultures in other components. A mixed linear model adjusted for random effects (the random effect being the infected patient) obtained convergence for the CFU/mm(2) variable, but could not confirm a significantly higher adherence to a particular component or to a particular biomaterial. Therefore, the bacterial adherence primarily depends on the infective microorganism and the response of each individual patient, rather than materials or components. PMID:22467526

  12. 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.

  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. Enantiomeric separation of tapentadol by capillary electrophoresis--study of chiral selectivity manipulation by various types of cyclodextrins.

    PubMed

    Znaleziona, Joanna; Fejős, Ida; Ševčík, Juraj; Douša, Michal; Béni, Szabolcs; Maier, Vítězslav

    2015-02-01

    The chiral recognition of the centrally acting analgesic agent tapentadol and its isomers with various cyclodextrins (CDs) was studied by capillary electrophoresis, focusing on the migration order of four stereoisomers. In the case of non-charged hydroxypropylated CDs (2-hydroxypropyl-β-CD, 2-hydroxypropyl-γ-CD) the beta derivative was able to discriminate the S,R- and R,S-isomers in acidic background electrolyte, whereas the gamma allowed the separation of S,S- and R,R-tapentadol, respectively. Dual CD system containing both hosts was used to separate all of four isomers. Negatively charged sulfated-α-CD at 1.0% (w/v) concentration in 100mM sodium borate buffer (pH 9.5) was capable of separating the isomers with favorable enantiomer migration order and the optimized method was able to determine 0.15% of chiral impurities of tapentadol in the presence of the last migrating clinically important R,R-isomer.

  15. Experimental study of flow separation control on a low- Re airfoil using leading-edge protuberance method

    NASA Astrophysics Data System (ADS)

    Zhang, M. M.; Wang, G. F.; Xu, J. Z.

    2014-04-01

    An experimental study of flow separation control on a low- Re c airfoil was presently investigated using a newly developed leading-edge protuberance method, motivated by the improvement in the hydrodynamics of the giant humpback whale through its pectoral flippers. Deploying this method, the control effectiveness of the airfoil aerodynamics was fully evaluated using a three-component force balance, leading to an effectively impaired stall phenomenon and great improvement in the performances within the wide post-stall angle range (22°-80°). To understand the flow physics behind, the vorticity field, velocity field and boundary layer flow field over the airfoil suction side were examined using a particle image velocimetry and an oil-flow surface visualization system. It was found that the leading-edge protuberance method, more like low-profile vortex generator, effectively modified the flow pattern of the airfoil boundary layer through the chordwise and spanwise evolutions of the interacting streamwise vortices generated by protuberances, where the separation of the turbulent boundary layer dominated within the stall region and the rather strong attachment of the laminar boundary layer still existed within the post-stall region. The characteristics to manipulate the flow separation mode of the original airfoil indicated the possibility to further optimize the control performance by reasonably designing the layout of the protuberances.

  16. 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.

  17. 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.

  18. Characterizing dense suspensions: two case studies from the pharmaceutical industry

    NASA Astrophysics Data System (ADS)

    Goldfarb, David J.; Khawaja, Nazia; Kazakevich, Irina; Bhattacharjee, Himanshu; Heslinga, Michael; Dalton, Chad

    2015-11-01

    Liquid suspensions of Active Pharmaceutical Ingredient powders are present as pharmaceutical dosage forms in the form of oral suspensions and injectables. We present two case studies, both dense (~ 30-40%) suspensions, in which the physical characterization of the product, specifically, particle size & shape and rheology were key to understanding the key product attributes as pertaining to the manufacturing process and to patient administration. For the one case study, an oral suspension, identifying variations in particle morphology during the wet milling of the product was key to the product understanding necessary to modify the milling process. Rheological measurements were applied as well. For the second case study, an injectable, results from different particle size measurement techniques and rheological measurements indicated the possibility of flocculation in a formulation. Additionally, measurements were obtained to assess the ``injectability'' of the product via rheometer and texture analyzer measurements and Poiseuille flow modeling. As a result, the relevant shear rate regime for this drug product administration was identified.

  19. X-ray diffraction and electron microscope study of phase separation in rod outer segment photoreceptor membrane multilayers.

    PubMed Central

    Gruner, S M; Rothschild, K J; Clark, N A

    1982-01-01

    Phase separation in artificially stacked multilayers of isolated bovine retinal rod outer segment (ROS) membranes has been examined via x-ray diffraction and electron microscopy. Specimens were prepared by isopotential spin drying followed with partial hydration by equilibration against moist gas streams. Upon dehydration, the multilamellar membrane phase assumes a binary phase composition consisting of concentrated protein-containing lamellae interspersed with microdomains of hexagonally packed tubes of lipid in a HII configuration. The HII lattice is geometrically coupled to the lamellar phase with one set of hexagonal crystal planes co-planar to the local membrane lamellae. The hexagonal microdomains bear a striking resemblance to the "paracrystalline inclusions" observed in fast-frozen, intact frog ROS (Corless and Costello. 1981. Exp. Eye Res. 32:217). The lamellar lattice is characterized by an unusually small degree of disorder. Sharp lamellar diffraction with a 120 A unit cell is observed (at near total dehydration) to a resolution of 6 A. A model consistent with the data is that a multilamellar array of ROS disks is stable as long as the external disk surfaces are kept sufficiently far apart. If the distance between the membranes is allowed to shrink below a certain critical value, the disk lipids spontaneously convert to a nonbilayer phase. This suggests that the structure of the ROS is stabilized by an internal framework that acts to keep the disks apart from one another and from the plasmalemma. Thus, the necessity of avoiding phase separations may provide a rationale for the peculiar morphology of the ROS. Images FIGURE 1 FIGURE 2 FIGURE 5 FIGURE 7 PMID:7139024

  20. 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.

  1. [Study of the Sporothrix schenkii (yeast forms) extract. Electrophoretic and immunoelectrophoretic analyses: characterization of enzymatic activities].

    PubMed

    Walbaum, S; Duriez, T; Dujardin, L; Biguet, J

    1978-07-28

    An extract from living yeast forms of S. schenckii was prepared. The yeasts originated from a shake culture in B.H.I. broth (Difco) incubated for 3 days at 35 degrees C in darkness; they were harvested, washed and disrupted with glass beads in a model MSK Braun mechanical cell homogenizer; a freezing-thawing was added to improve the extract. After electrophoretic separation in agarose gel, the extract's components were characterized by their enzymic activity; with this technique, 30 bands were revealed. These enzymic activities were also investigated on the antigenic fractions of the extract revealed by a rabbit hyperimmunserum: 16 among 22 immunoprecipitates are identified by their catalytic properties. Study of the earliest precipitating antibodies (appearing-order and enzymic caracterization) in rabbits just immunized completes this work. How to ameliorate the quality of the extract by culture and extraction conditions is also specified. PMID:692628

  2. A Kinetic Study of DDGS Hemicellulose Acid Hydrolysis and NMR Characterization of DDGS Hydrolysate.

    PubMed

    Chen, Hanchi; Liu, Shijie

    2015-09-01

    Liquid hot water (LHW) extraction was used as a pretreatment method to separate the hemicellulose fraction from dried distiller's grain with solubles (DDGS) into liquid phase. Acid hydrolysis using 3.264 % w/w sulfuric acid at 130 °C was performed to convert polysaccharides in LHW extract to monosaccharides. The structure characterization of DDGS in anomeric carbon region based on proton NMR and heteronuclear single quantum coherence (HSQC) during acid hydrolysis was studied in this work. It reveals that the sugar units in DDGS hemicelluloses are constructed with (1-4)-β-D-xylopyranose and α-L-arabinofuranosyl residues. A kinetic model is included to explain the changing concentration of monomer, oligomer, and sugar units. The model was further tested based on the changing concentration of five carbon sugar units during hydrolysis. PMID:26198022

  3. 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

  4. Characterization and Study of Transgenic Cultivars by Capillary and Microchip Electrophoresis

    PubMed Central

    Domínguez Vega, Elena; Marina, Maria Luisa

    2014-01-01

    Advances in biotechnology have increased the demand for suitable analytical techniques for the analysis of genetically modified organisms. Study of the substantial equivalence, discrimination between transgenic and non-transgenic cultivars, study of the unintended effects caused by a genetic modification or their response to diverse situations or stress conditions (e.g., environmental, climatic, infections) are some of the concerns that need to be addressed. Capillary electrophoresis (CE) is emerging as an alternative to conventional techniques for the study and characterization of genetically modified organisms. This article reviews the most recent applications of CE for the analysis and characterization of transgenic cultivars in the last five years. Different strategies have been described depending on the level analyzed (DNA, proteins or metabolites). Capillary gel electrophoresis (CGE) has shown to be particularly useful for the analysis of DNA fragments amplified by PCR. Metabolites and proteins have been mainly separated using capillary zone electrophoresis (CZE) using UV and MS detection. Electrophoretic chips have also proven their ability in the analysis of transgenic cultivars and a section describing the new applications is also included. PMID:25535077

  5. Characterization and study of transgenic cultivars by capillary and microchip electrophoresis.

    PubMed

    Domínguez Vega, Elena; Marina, Maria Luisa

    2014-01-01

    Advances in biotechnology have increased the demand for suitable analytical techniques for the analysis of genetically modified organisms. Study of the substantial equivalence, discrimination between transgenic and non-transgenic cultivars, study of the unintended effects caused by a genetic modification or their response to diverse situations or stress conditions (e.g., environmental, climatic, infections) are some of the concerns that need to be addressed. Capillary electrophoresis (CE) is emerging as an alternative to conventional techniques for the study and characterization of genetically modified organisms. This article reviews the most recent applications of CE for the analysis and characterization of transgenic cultivars in the last five years. Different strategies have been described depending on the level analyzed (DNA, proteins or metabolites). Capillary gel electrophoresis (CGE) has shown to be particularly useful for the analysis of DNA fragments amplified by PCR. Metabolites and proteins have been mainly separated using capillary zone electrophoresis (CZE) using UV and MS detection. Electrophoretic chips have also proven their ability in the analysis of transgenic cultivars and a section describing the new applications is also included. PMID:25535077

  6. 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.

  7. 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

  8. [Advances in multidimensional high performance liquid chromatography for separation technology in proteomic study].

    PubMed

    Gao, Mingxia; Guan, Xia; Hong, Guangfeng; Zhang, Xiangmin

    2009-09-01

    With the developments of proteomic study, multidimensional high performance liquid chromatography technology has attracted increasing interests due to its obvious advantages, such as rapid analysis, high automation and easy combination with mass spectrometry and so on. This review emphasizes the advances of multidimensional high performance liquid chromatography technology, including classical bottom-up methods, top-down techniques and array-based two-dimensional liquid chromatography system, which was designed and set up by our lab to improve the throughput. These techniques showed promising potential applications in proteomics study.

  9. 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…

  10. 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.

  11. Quantitative and qualitative approaches in the study of poverty and adolescent development: separation or integration?

    PubMed

    Leung, Janet T Y; Shek, Daniel T L

    2011-01-01

    This paper examines the use of quantitative and qualitative approaches to study the impact of economic disadvantage on family processes and adolescent development. Quantitative research has the merits of objectivity, good predictive and explanatory power, parsimony, precision and sophistication of analysis. Qualitative research, in contrast, provides a detailed, holistic, in-depth understanding of social reality and allows illumination of new insights. With the pragmatic considerations of methodological appropriateness, design flexibility, and situational responsiveness in responding to the research inquiry, a mixed methods approach could be a possibility of integrating quantitative and qualitative approaches and offers an alternative strategy to study the impact of economic disadvantage on family processes and adolescent development. PMID:21870673

  12. Separating the contributions of primary and unwanted cues in psychophysical studies.

    PubMed

    Dai, Huanping; Micheyl, Christophe

    2012-10-01

    A fundamental issue in the design and the interpretation of experimental studies of perception relates to the question of whether the participants in these experiments could perform the perceptual task assigned to them using another feature, or cue, than that intended by the experimenter. An approach frequently used by auditory- and visual-perception researchers to guard against this possibility involves applying random variations to the stimuli across presentations or trials so as to make the "unwanted" cue unreliable for the participants. However, the theoretical basis of this widespread practice is not well developed. In this article, we describe a 2-channel model based on general principles of psychophysical signal detection theory, which can be used to assess the respective contributions of the unwanted cue and of the primary cue to performance or thresholds measured in perceptual discrimination experiments involving stimulus randomization. Example applications of the model to the analysis of results obtained in representative studies from the auditory- and visual-perception literature are provided. In several cases, the results of the model-based analyses indicate that the effectiveness of the randomization procedure was less than originally assumed by the authors of these studies. These findings underscore the importance of quantifying the potential influence of unwanted cues on the results of psychophysical experiments, even when stimulus randomization is used. PMID:22844984

  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. 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.

  15. 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.

  16. Yucca Mountain Site Characterization Project exploratory studies facilities construction status

    SciTech Connect

    Allan, J.N.; Leonard, T.M.

    1993-12-31

    This paper discusses the progress to date on the construction planning and development of the Yucca Mountain Site Characterization Project (YMP) Exploratory Studies Facilities (ESF). The purpose of the ESF is to determine early site suitability and to characterize the subsurface of the Yucca Mountain site to assess its suitability for a potential high level nuclear waste repository. The present ESF configuration concept is for two main ramps to be excavated by tunnel boring machines (TBM) from the surface to the Topopah Spring Member of the Paintbrush Tuff Formation. From the main ramps, slightly above Topopah Spring level, supplemental ramps will be penetrated to the Calico Hills formation below the potential repository. There will be exploratory development drifts driven on both levels with the Main Test Area being located on the Topopah Spring level, which is the level of the proposed repository. The Calico Hills formation lies below the Topopah Spring member and is expected to provide the main geo-hydrologic barrier between the potential repository and the underlying saturated zones in the Crater Flat Tuff.

  17. Solid waste characterization, quantification and management practices in developing countries. a case study: Nablus district - Palestine.

    PubMed

    Al-Khatib, Issam A; Monou, Maria; Abu Zahra, Abdul Salam F; Shaheen, Hafez Q; Kassinos, Despo

    2010-05-01

    Solid waste management (SWM) is one of the most challenging issues faced by developing countries that suffer from serious pollution problems caused by the generation of large waste quantities. This paper presents the case study of SWM in the Nablus district - Palestine. Surveys for household residents' and SWM program operators, field investigations, on-site waste measurements and characterizations were conducted. Per capita waste generation rates varied between different localities although trends were similar. Overall, the majority of waste was organic (65.1% by weight), suggesting a strong resource recovery potential in terms of animal feed or compost. Recyclable waste (plastic, paper and card) made up 16.7% by weight the waste composition suggesting an incentive to introduce source separation. Household attitudes complemented the waste characterization study, revealing the main problems faced. SWM operators quoted on the current status, highlighting problems with disposing in unsanitary landfills, ineffective solid waste fees system, increasing solid waste quantities and lacking equipment and experienced personnel. To enhance sustainable SWM, public awareness, funding, expertise, equipment and facilities and other provisions currently lacking or inappropriate must be provided.

  18. Numerical Study of the ``End of the Vortex'' Phenomenon in a Hydrocyclone Separator

    NASA Astrophysics Data System (ADS)

    Chang, Yu-Fen; Pisarev, Gleb I.; Hoffmann, Alex C.

    2011-09-01

    The single-phase flow field in a hydrocyclone was studied numerically using the LES turbulence model. The hydrocyclone geometry and flow conditions are in accordance with previous experimental work. An important phenomenon in cyclone operation, the "end of the vortex," observed in experiments was reproduced in the simulations, where the vortex end deviated from the vortex axis and bent to the wall of the hydrocyclone body. As the vortex end attached to the wall, its rotation (precession) was visualized by monitoring the motion of the low-pressure spot caused by the vortex core on the wall.

  19. A general framework for characterizing studies of brain interface technology.

    PubMed

    Mason, S G; Jackson, M M Moore; Birch, G E

    2005-11-01

    The development of brain interface (BI) technology continues to attract researchers with a wide range of backgrounds and expertise. Though the BI community is committed to accurate and objective evaluation of methods, systems, and technology, the very diversity of the methods and terminology used in the field hinders understanding and impairs technology cross-fertilization and cross-group validation of findings. Underlying this dilemma is a lack of common perspective and language. As seen in our previous works in this area, our approach to remedy this problem is to propose language in the form of taxonomy and functional models. Our intent is to document and validate our best thinking in this area and publish a perspective that will stimulate discussion. We encourage others to do the same with the belief that focused discussion on language issues will accelerate the inherently slow natural evolution of language selection and thus alleviate related problems. In this work, we propose a theoretical framework for describing BI-technology-related studies. The proposed framework is based on the theoretical concepts and terminology from classical science, assistive technology development, human-computer interaction, and previous BI-related works. Using a representative set of studies from the literature, the proposed BI study framework was shown to be complete and appropriate perspective for thoroughly characterizing a BI study. We have also demonstrated that this BI study framework is useful for (1) objectively reviewing existing BI study designs and results, (2) comparing designs and results of multiple BI studies, (3) designing new studies or objectively reporting BI study results, and (4) facilitating intra- and inter-group communication and the education of new researchers. As such, it forms a sound and appropriate basis for community discussion.

  20. 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.

  1. A quantum chemistry study for ionic liquids applied to gas capture and separation.

    PubMed

    Damas, Giane B; Dias, Amina B A; Costa, Luciano T

    2014-07-31

    In recent years, the global climate change is in evidence and it is almost a consensus that it is caused by the greenhouse gases emissions. An alternative to reduce these emissions is carbon capture and storage (CCS), which employs solvents based on amine compounds. In this scene, ionic liquids (IL) have been investigated to a greater extent for this application. In this work, we make an evaluation of interactions between gases (CO2, SO2, and H2S) and anion/cation from IL, as well as cation-anion interactions. For this, quantum calculations under vacuum were performed at the B3LYP/6-311+G** level of theory and using the M06-2X functional, where dispersion effects are considered. Among the well-studied systems based on imidazolium cations and fluorinated anions, we also studied the tetraalkylammonium, tetraalkylphosphonium, ether-functionalized imidazolium based systems, and tetrahexylammonium bis(trifluoromethanesulfonyl)imide, [THA][Tf2N], as a potential prototype. The ion pairs evaluated include [Tf2N](-)-based IL, with alkyl chain varying from [C1mim](+) to [C8mim](+) and [C1mim](+)-based IL. We found that the anion becomes more available to interact with gas with the weakening of the cation-anion interaction. [THA][Tf2N] has a binding energy of -274.89 kJ/mol at the B3LYP/6-311+G** level of theory, which is considered energetically interesting to gas capture applications.

  2. 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.

  3. Fundamental studies of separation processes. Technical progress report, 15 August 1979-14 August 1980

    SciTech Connect

    Rogers, L.B.

    1980-01-01

    During the past year, four technical reports have been issued. These have dealt with relative retentions in gas chromatography of the sulfur isotopes in COS, CS/sub 2/ and SO/sub 2/, fractionations of oligomers in commercial polystyrene, identifications of classes of compounds removed from different types of carbonaceous materials by supercritical pentane, and a comparison of the speed of a system of multiple isothermal columns with that of a programmed-temperature column for the fractionation of a mixture of compounds covering a wide range of boiling points. Other studies have involved optimization of the recycle mode in gas chromatography, selective weighting of peaks in the measurement of information conveyed by a chromatogram, development of procedures for the isolations of various vanadium compounds from Venezuelan crude oil, and evaluation of the effect of organic ligand on the sensitivity of the flame emission signal observed for vanadium.

  4. 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.

  5. 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)

  6. 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.

  7. Hybrid Enrichment Verification Array: Module Characterization Studies Version 2

    SciTech Connect

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

    2015-12-01

    The work presented in this report is focused on the characterization and refinement of the 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. 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.

  8. Systematic analytical characterization of new psychoactive substances: A case study.

    PubMed

    Lobo Vicente, Joana; Chassaigne, Hubert; Holland, Margaret V; Reniero, Fabiano; Kolář, Kamil; Tirendi, Salvatore; Vandecasteele, Ine; Vinckier, Inge; Guillou, Claude

    2016-08-01

    New psychoactive substances (NPS) are synthesized compounds that are not usually covered by European and/or international laws. With a slight alteration in the chemical structure of existing illegal substances registered in the European Union (EU), these NPS circumvent existing controls and are thus referred to as "legal highs". They are becoming increasingly available and can easily be purchased through both the internet and other means (smart shops). Thus, it is essential that the identification of NPS keeps up with this rapidly evolving market. In this case study, the Belgian Customs authorities apprehended a parcel, originating from China, containing two samples, declared as being "white pigments". For routine identification, the Belgian Customs Laboratory first analysed both samples by gas-chromatography mass-spectrometry and Fourier-Transform Infrared spectroscopy. The information obtained by these techniques is essential and can give an indication of the chemical structure of an unknown substance but not the complete identification of its structure. To bridge this gap, scientific and technical support is ensured by the Joint Research Centre (JRC) to the European Commission Directorate General for Taxation and Customs Unions (DG TAXUD) and the Customs Laboratory European Network (CLEN) through an Administrative Arrangement for fast recognition of NPS and identification of unknown chemicals. The samples were sent to the JRC for a complete characterization using advanced techniques and chemoinformatic tools. The aim of this study was also to encourage the development of a science-based policy driven approach on NPS. These samples were fully characterized and identified as 5F-AMB and PX-3 using (1)H and (13)C nuclear magnetic resonance (NMR), high-resolution tandem mass-spectrometry (HR-MS/MS) and Raman spectroscopy. A chemoinformatic platform was used to manage, unify analytical data from multiple techniques and instruments, and combine it with chemical and

  9. Systematic analytical characterization of new psychoactive substances: A case study.

    PubMed

    Lobo Vicente, Joana; Chassaigne, Hubert; Holland, Margaret V; Reniero, Fabiano; Kolář, Kamil; Tirendi, Salvatore; Vandecasteele, Ine; Vinckier, Inge; Guillou, Claude

    2016-08-01

    New psychoactive substances (NPS) are synthesized compounds that are not usually covered by European and/or international laws. With a slight alteration in the chemical structure of existing illegal substances registered in the European Union (EU), these NPS circumvent existing controls and are thus referred to as "legal highs". They are becoming increasingly available and can easily be purchased through both the internet and other means (smart shops). Thus, it is essential that the identification of NPS keeps up with this rapidly evolving market. In this case study, the Belgian Customs authorities apprehended a parcel, originating from China, containing two samples, declared as being "white pigments". For routine identification, the Belgian Customs Laboratory first analysed both samples by gas-chromatography mass-spectrometry and Fourier-Transform Infrared spectroscopy. The information obtained by these techniques is essential and can give an indication of the chemical structure of an unknown substance but not the complete identification of its structure. To bridge this gap, scientific and technical support is ensured by the Joint Research Centre (JRC) to the European Commission Directorate General for Taxation and Customs Unions (DG TAXUD) and the Customs Laboratory European Network (CLEN) through an Administrative Arrangement for fast recognition of NPS and identification of unknown chemicals. The samples were sent to the JRC for a complete characterization using advanced techniques and chemoinformatic tools. The aim of this study was also to encourage the development of a science-based policy driven approach on NPS. These samples were fully characterized and identified as 5F-AMB and PX-3 using (1)H and (13)C nuclear magnetic resonance (NMR), high-resolution tandem mass-spectrometry (HR-MS/MS) and Raman spectroscopy. A chemoinformatic platform was used to manage, unify analytical data from multiple techniques and instruments, and combine it with chemical and

  10. Synthesis, characterization, and metabolism studies of fluspidine enantiomers.

    PubMed

    Holl, Katharina; Falck, Evamaria; Köhler, Jens; Schepmann, Dirk; Humpf, Hans-Ulrich; Brust, Peter; Wünsch, Bernhard

    2013-12-01

    The enantiomers of the potent σ1 ligand fluspidine (1) were prepared by using chiral preparative HPLC. Synthesis of racemic tosylate 2 and subsequent separation of enantiomers yielded (R)-2 and (S)-2 in excellent enantiomeric purities. The fluspidine enantiomers (R)-1 and (S)-1 were synthesized from (R)-2 and (S)-2 by nucleophilic substitution with tetra-n-butylammonium fluoride, affording (R)-1 with 99.6 % ee and (S)-1 with 96.4 % ee. Tosylates (R)-2 and (S)-2 can also serve as precursors for the radiosynthesis of enantiomerically pure radiotracers [(18) F](R)-1 and [(18) F](S)-1. The absolute configuration of the pure enantiomers was elucidated by comparison of their CD spectra with a calculated CD spectrum of a simplified model compound. In receptor binding studies, both enantiomers displayed very high σ1 receptor affinity and selectivity against the σ2 receptor. (R)-Fluspidine ((R)-1) is the eutomer, with a Ki value of 0.57 nM and a eudysmic ratio of 4. Incubation of (R)-1 and (S)-1 with rat liver microsomes led to the identification of seven and eight metabolites, respectively. Although the S-configured enantiomer formed additional metabolite (S)-1-3, it is metabolically more stable than (R)-1.

  11. Phase separation and ordering process in Al-Li alloys studied by small-angle neutron scattering and neutron diffraction

    SciTech Connect

    Furusaka, M.; Fujikawa, S.I.; Tranquada, J.M.

    1993-07-01

    To study phase separation kinetics of Al-9.5at.%Li polycrystalline alloys in which precipitates have ordered Al{sub 3}Li ({delta}{prime}) structure, profile analysis of small-angle neutron scattering and superlattice reflections (100) and (110) were done. A small-angle scattering instrument and a triple-axis spectrometer in elastic mode were used in the measurements. Strong texture was observed in the reflections. Therefore, measurements were done using the crystal orientation where the intensity of the reflection was at the maximum. Profiles of small-angle scattering and superlattice reflections were almost identical at higher momentum transfer side. At lower momentum transfer side, small-angle scattering showed interference effects, but superlattice reflection did not show any sign of interference. Integrated intensities of superlattice reflections were obtained and compared with small-angle scattering intensity. The order parameter was not saturated in the {delta}{prime} precipitates at the early stage of the phase separation process.

  12. Pharmacokinetic and pharmacodynamic study of a phospholipid-based phase separation gel for once a month administration of octreotide.

    PubMed

    Wang, Mengxin; Shan, Fengying; Zou, Yang; Sun, Xun; Zhang, Zhi-Rong; Fu, Yao; Gong, Tao

    2016-05-28

    As a natural somatostatin analog, octreotide acetate (OCT) has been extensively used in cancer treatment and growth hormone related diseases. The clinical application of OCT, however, is greatly limited by its short half-life, rapid elimination and clearance in vivo. In the current study, a high content phospholipid-based phase separation gel platform (PPSG) was presented, which could be injected in the soluble state and underwent rapid phase-separation into a gel-like implant after a single subcutaneous injection. OCT was dispersed homogeneously in the PPSG pre-gel solution to afford OCT-loaded PPSG (OCT-PPSG) after a single subcutaneous injection, which displayed controlled and sustained release profiles for up to 30days in rats, rabbits and Beagle dogs. OCT-PPSG showed a less significant burst phase followed by a steady plasma concentration of OCT compared with Sandostatin(®) (LAR) in Beagle dogs. Moreover, OCT-PPSG was demonstrated to show remarkable antitumor efficacy in both a primary rat model and a xenograft mouse model of hepatocellular carcinoma (HCC). PPSG thus represented a promising and viable in situ forming gel platform material for the long-term sustained release of peptides and protein drugs.

  13. 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.

  14. Synthesis, characterization and antimicrobial studies of Schiff base complexes

    NASA Astrophysics Data System (ADS)

    Zafar, Hina; Ahmad, Anis; Khan, Asad U.; Khan, Tahir Ali

    2015-10-01

    The Schiff base complexes, MLCl2 [M = Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)] have been synthesized by the template reaction of respective metal ions with 2-acetylpyrrole and 1,3-diaminopropane in 1:2:1 M ratio. The complexes have been characterized by elemental analyses, ESI - mass, NMR (1H and 13C), IR, XRD, electronic and EPR spectral studies, magnetic susceptibility and molar conductance measurements. These studies show that all the complexes have octahedral arrangement around the metal ions. The molar conductance measurements of all the complexes in DMSO indicate their non-electrolytic nature. The complexes were screened for their antibacterial activity in vitro against Gram-positive (Streptococcus pyogenes) and Gram-negative (Klebsiella pneumoniae) bacteria. Among the metal complexes studied the copper complex [CuLCl2], showed highest antibacterial activity nearly equal to standard drug ciprofloxacin. Other complexes also showed considerable antibacterial activity. The relative order of activity against S. Pyogenes is as Cu(II) > Zn(II) > Co(II) = Fe(II) > Ni(II) and with K. Pneumonia is as Cu(II) > Co(II) > Zn(II) > Fe(II) > Ni(II).

  15. Docetaxel loaded chitosan nanoparticles: formulation, characterization and cytotoxicity studies.

    PubMed

    Jain, Ankit; Thakur, Kanika; Kush, Preeti; Jain, Upendra K

    2014-08-01

    The primary objective of the present investigation was to explore biodegradable chitosan as a polymeric material for formulating docetaxel nanoparticles (DTX-NPs) to be used as a delivery system for breast cancer treatment. Docetaxel loaded chitosan nanoparticles were formulated by water-in-oil nanoemulsion system and characterized in terms of particle size, zeta potential, polydispersity index, drug entrapment efficiency (EE), loading capacity (LC), scanning electron microscopy (SEM), in vitro release study and drug release kinetics. Further, to evaluate the potential anticancer efficacy of docetaxel loaded chitosan nanoparticulate system, in vitro cytotoxicity studies on human breast cancer cell line (MDA-MB-231) were carried out. The morphological studies revealed the spherical shape of docetaxel loaded chitosan nanoparticles having an average size of 170.1±5.42-227.6±7.87nm, polydispersity index in the range of 0.215±0.041-0.378±0.059 and zeta potential between 28.3 and 31.4mV. Nanoparticles exhibited 65-76% of drug entrapment and 8-12% loading capacity releasing about 68-83% of the drug within 12h following Higuchi's square-root kinetics. An increase of 20% MDA-MB-231 cell line growth inhibition was determined by docetaxel loaded chitosan nanoparticles with respect to the free drug after 72h incubation.

  16. A comparative study of Sephadex, glass wool and Percoll separation techniques on sperm quality and IVF results for cryopreserved bovine semen.

    PubMed

    Lee, Hae-Lee; Kim, Sue-Hee; Ji, Dong-Beom; Kim, Yong-Jun

    2009-09-01

    The aim of this study was to compare the effects of spermatozoa separation techniques on sperm quality and in-vitro fertilization (IVF) results for cryopreserved bovine semen. Sephadex, glass wool and Percoll gradient separation techniques were used for sperm separation and sperm motility, morphology and membrane integrity were evaluated before and after separation. Also, cleavage and blastocyst developmental rate were investigated after IVF with sperm recovered by each separation technique. The motility of samples obtained by the three separation techniques were greater compared to the control samples (p < 0.05). The percentage of spermatozoa with intact plasma-membrane integrity, identified by 6-carboxyfluoresceindiacetate/ propidium iodide fluorescent staining and the hypo-osmotic swelling test, was highest in the glass wool filtration samples (p < 0.05). The cleavage and blastocyst rate of total oocytes produced from glass wool filtration samples were also higher than the control and Sephadex filtration samples (p < 0.05), but were not significantly different from Percoll separation samples. However, a significantly greater number of cleaved embryos produced by glass wool filtration developed to blastocyst stage than those produced by Percoll separation (p < 0.05). These results indicate that spermatozoa with good quality can be achieved by these three separation techniques and can be used for bovine IVF. In particular, it suggests that glass wool filtration would be the most effective method of the three for improving sperm quality and embryo production for cryopreserved bovine spermatozoa.

  17. Characterization study of heavy metal-bearing phases in MSW slag.

    PubMed

    Saffarzadeh, Amirhomayoun; Shimaoka, Takayuki; Motomura, Yoshinobu; Watanabe, Koichiro

    2009-05-30

    Slag products derived from the pyrolysis/melting and plasma/melting treatment of municipal solid waste (MSW) in Japan were examined for the characterization study of heavy metal-bearing phases using petrographic techniques. Detailed microscopic observations revealed that the shapes of heavy metal-rich inclusions are generally spherical to semi-spherical and their sizes range from submicron to scarcely large size spheres (over 100 microm). The experiments (both optical microscopy and electron probe microanalysis) indicated that Fe and Cu participate in mutual substitution and different proportions, and form mainly two-phase Fe-Cu alloys that bound in the silicate glass. This alloy characterizes the composition of more than 80% of the metal-rich inclusions. Other metals and non-metals (such as Pb, Ni, Sb, Sn, P, Si, Al and S) with variable amounts and uneven distributions are also incorporated in the Fe-Cu alloy. In average, the bulk concentration of heavy metals in samples from pyrolysis/melting type is almost six times greater than samples treated under plasma/arc processing. The observations also confirmed that slag from pyrolysis origin contains remarkably higher concentration of metallic inclusions than slag from plasma treatment. In the latter, the metallic compounds are separately tapped from molten slag during the melting treatment that might lead to the generation of safer slag product for end users from environmental viewpoint. PMID:18926624

  18. Multitechnique characterization of lapis lazuli for provenance study.

    PubMed

    Lo Giudice, Alessandro; Re, Alessandro; Calusi, Silvia; Giuntini, Lorenzo; Massi, Mirko; Olivero, Paolo; Pratesi, Giovanni; Albonico, Maria; Conz, Elisa

    2009-12-01

    Lapis lazuli is one of the oldest precious stone, being used for glyptic as early as 7,000 years ago: jewels, amulets, seals, and inlays are examples of objects produced using this material. Only a few sources of lapis lazuli exist in the world due to the low probability of geological conditions in which it can form, so that the possibility to associate the raw material to man-made objects helps to reconstruct trade routes. Since art objects produced using lapis lazuli are valuable, only nondestructive investigations can be carried out to identify the provenance of the raw materials. Ionoluminescence (IL) is a good candidate for this task. Similar to cathodoluminescence (CL), IL consists in the collection of luminescence spectra induced by megaelectronvolt ion (usually protons) irradiation. The main advantage of IL consists in the possibility of working in air while measuring simultaneously the composition of major and trace elements by means of complementary ion beam analysis techniques like particle-induced X-ray emission (PIXE) or particle-induced gamma-ray emission (PIGE). In the present work, a systematic study of the luminescence properties of lapis lazuli under charged particle irradiation is reported. In the first phase, a multitechnique approach was adopted (CL, scanning electron microscopy with microanalysis, micro-Raman) to characterize luminescent minerals. This characterization was propaedeutic for IL/PIXE/PIGE measurements carried out on significant areas selected on the basis of results obtained previously. Criteria to identify provenance of lapis lazuli from four of the main sources (Afghanistan, Pamir Mountains in Tajikistan, Chile, and Siberia) were proposed. PMID:19705108

  19. Multitechnique characterization of lapis lazuli for provenance study.

    PubMed

    Lo Giudice, Alessandro; Re, Alessandro; Calusi, Silvia; Giuntini, Lorenzo; Massi, Mirko; Olivero, Paolo; Pratesi, Giovanni; Albonico, Maria; Conz, Elisa

    2009-12-01

    Lapis lazuli is one of the oldest precious stone, being used for glyptic as early as 7,000 years ago: jewels, amulets, seals, and inlays are examples of objects produced using this material. Only a few sources of lapis lazuli exist in the world due to the low probability of geological conditions in which it can form, so that the possibility to associate the raw material to man-made objects helps to reconstruct trade routes. Since art objects produced using lapis lazuli are valuable, only nondestructive investigations can be carried out to identify the provenance of the raw materials. Ionoluminescence (IL) is a good candidate for this task. Similar to cathodoluminescence (CL), IL consists in the collection of luminescence spectra induced by megaelectronvolt ion (usually protons) irradiation. The main advantage of IL consists in the possibility of working in air while measuring simultaneously the composition of major and trace elements by means of complementary ion beam analysis techniques like particle-induced X-ray emission (PIXE) or particle-induced gamma-ray emission (PIGE). In the present work, a systematic study of the luminescence properties of lapis lazuli under charged particle irradiation is reported. In the first phase, a multitechnique approach was adopted (CL, scanning electron microscopy with microanalysis, micro-Raman) to characterize luminescent minerals. This characterization was propaedeutic for IL/PIXE/PIGE measurements carried out on significant areas selected on the basis of results obtained previously. Criteria to identify provenance of lapis lazuli from four of the main sources (Afghanistan, Pamir Mountains in Tajikistan, Chile, and Siberia) were proposed.

  20. Characterizing human retinotopic mapping with conformal geometry: a preliminary study

    NASA Astrophysics Data System (ADS)

    Ta, Duyan; Shi, Jie; Barton, Brian; Brewer, Alyssa; Lu, Zhong-Lin; Wang, Yalin

    2014-03-01

    Functional magnetic resonance imaging (fMRI) has been widely used to measure the retinotopic organization of early visual cortex in the human brain. Previous studies have identified multiple visual field maps (VFMs) based on statistical analysis of fMRI signals, but the resulting geometry has not been fully characterized with mathematical models. Here we test whether VFMs V1 and V2 obey the least restrictive of all geometric mappings; that is, whether they are anglepreserving and therefore maintain conformal mapping. We measured retinotopic organization in individual subjects using standard traveling-wave fMRI methods. Visual stimuli consisted of black and white, drifting checkerboards comprising rotating wedges and expanding rings to measure the cortical representations of polar angle and eccentricity, respectively. These representations were then projected onto a 3D cortical mesh of each hemisphere. By generating a mapped unit disk that is conformal of the VFMs using spherical stereographic projection and computing the parameterized coordinates of the eccentricity and polar angle gradients, we computed Beltrami coefficients to check whether the mapping from the visual field to the V1 and V2 cortical representations is conformal. We find that V1 and V2 exhibit local conformality. Our analysis of the Beltrami coefficient shows that selected regions of V1 and V2 that contain reasonably smooth eccentricity and polar angle gradients do show significant local conformality, warranting further investigation of this approach for analysis of early and higher visual cortex. These results suggest that such a mathematical model can be used to characterize the early VFMs in human visual cortex.

  1. 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.

  2. Gas separating

    DOEpatents

    Gollan, Arye Z. [Newton, MA

    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.

  3. A new classification paradigm of extracellular polymeric substances (EPS) in activated sludge: separation and characterization of exopolymers between floc level and microcolony level.

    PubMed

    Wang, Bin-Bin; Chang, Qing; Peng, Dang-Cong; Hou, Yin-Ping; Li, Hui-Juan; Pei, Li-Ying

    2014-11-01

    Extracellular polymeric substances (EPS) play a crucial role in the formation of activated sludge flocs. However, until now, the EPS are rather classified by the method used for extraction than by a theoretical consideration of their function and composition. In this paper, a new classification paradigm of EPS was proposed, which offered a novel approach to identify the role of EPS in the formation of activated sludge flocs. The current study gave an exploration to distinguish the EPS in the floc level (extra-microcolony polymers, EMPS) and in the microcolony level (extra-cellular polymers, ECPS). It was found that cation exchange resin treatment is efficient to disintegrate the flocs for EMPS extraction, however, inefficient to disaggregate the microcolonies for ECPS harvesting. A two-steps extraction strategy (cation exchange resin treatment followed by ultrasonication-high speed centrifugation treatment) was suggested to separate these two types of EPS in activated sludge flocs and the physicochemical characteristics of EMPS and ECPS were compared. The protein/polysaccharide ratio of ECPS was higher than that of EMPS and the molecular weight of proteins in EMPS and ECPS were found to be different. The ECPS contained higher molecular weight proteins and more hydrophobic substances than the EMPS contained. The result of excitation-emission matrix fluorescence spectroscopy analysis also showed that the EMPS and the ECPS have different fluorescent expressions and the components of EMPS were more diverse than that of ECPS. All results reported herein demonstrated that two different types of exopolymers exist in the activated sludge flocs and the inter-particle forces for aggregation of activated sludge flocs are not identical between the floc level and the microcolony level. It suggested that cation bridging interactions are more crucial in floc level flocculation, while the entanglement and hydrophobic interactions are more important in microcolony level cohesion.

  4. Aquifer characterization using geoelectrical modelling, a case study

    NASA Astrophysics Data System (ADS)

    Meyer, Rena; Sauter, Martin; Weller, Andreas

    2014-05-01

    Surface geophysical investigations offer inexpensive and complementary information for hydrogeological issues. The quality and feasibility of geophysical models can be improved considerably by incorporating geological and hydrogeological a-priori information. In the presented study, densely spaced surface geoelectrical measurements were performed at the hydrogeological testsite Stegemühle, Göttingen, Germany. Twelve parallel profiles, 100 m long, with an electrode spacing of 0.5 m were measured using the averaged half Wenner configuration. The study area consists of a gravel-sand partially confined aquifer. Thanks to former studies a good hydraulic and geological data base is available. Vertical electrical soundings (VES) as well as 2D and 3D inversions were carried out with the purpose of building a subsurface resistivity model of the aquifer. Commercial software (res2/3Dinv) as well as non-commercial inversion algorithms (VES4, AC2DSIRT) are applied for data analysis. The interpretation of geoelectrical models generally suffers an ambiguity due to the principle of equivalence that hinders the independent determination of layer resistivity and thickness. To overcome this problem, information from certain borehole profiles and conductivity logs were included to calibrate VES and constrain AC2DSIRT modelling. Inversions using AC2DSIRT with an initial model according to the calibrated results of VES generate a 2D resistivity distribution that is significantly more feasible in terms of root mean square and geological data than those without any constraints. Apart from this, a field specific linear relationship between electrical resistivity and hydraulic conductivity is determined at six well locations. This relation is used to extrapolate the hydraulic conductivity distribution over the whole study area. In conclusion, the presented field study shows the importance of integration of a-priori geological and hydrological information to improve the output of

  5. 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.

  6. Component separations.

    PubMed

    Heller, Lior; McNichols, Colton H; Ramirez, Oscar M

    2012-02-01

    Component separation is a technique used to provide adequate coverage for midline abdominal wall defects such as a large ventral hernia. This surgical technique is based on subcutaneous lateral dissection, fasciotomy lateral to the rectus abdominis muscle, and dissection on the plane between external and internal oblique muscles with medial advancement of the block that includes the rectus muscle and its fascia. This release allows for medial advancement of the fascia and closure of up to 20-cm wide defects in the midline area. Since its original description, components separation technique underwent multiple modifications with the ultimate goal to decrease the morbidity associated with the traditional procedure. The extensive subcutaneous lateral dissection had been associated with ischemia of the midline skin edges, wound dehiscence, infection, and seroma. Although the current trend is to proceed with minimally invasive component separation and to reinforce the fascia with mesh, the basic principles of the techniques as described by Ramirez et al in 1990 have not changed over the years. Surgeons who deal with the management of abdominal wall defects are highly encouraged to include this technique in their collection of treatment options.

  7. Characterizing parameters of Jatropha curcas cell cultures for microgravity studies

    NASA Astrophysics Data System (ADS)

    Vendrame, Wagner A.; Pinares, Ania

    2013-06-01

    Jatropha (Jatropha curcas) is a tropical perennial species identified as a potential biofuel crop. The oil is of excellent quality and it has been successfully tested as biodiesel and in jet fuel mixes. However, studies on breeding and genetic improvement of jatropha are limited. Space offers a unique environment for experiments aiming at the assessment of mutations and differential gene expression of crops and in vitro cultures of plants are convenient for studies of genetic variation as affected by microgravity. However, before microgravity studies can be successfully performed, pre-flight experiments are necessary to characterize plant material and validate flight hardware environmental conditions. Such preliminary studies set the ground for subsequent spaceflight experiments. The objectives of this study were to compare the in vitro growth of cultures from three explant sources (cotyledon, leaf, and stem sections) of three jatropha accessions (Brazil, India, and Tanzania) outside and inside the petriGAP, a modified group activation pack (GAP) flight hardware to fit petri dishes. In vitro jatropha cell cultures were established in petri dishes containing a modified MS medium and maintained in a plant growth chamber at 25 ± 2 °C in the dark. Parameters evaluated were surface area of the explant tissue (A), fresh weight (FW), and dry weight (DW) for a period of 12 weeks. Growth was observed for cultures from all accessions at week 12, including subsequent plantlet regeneration. For all accessions differences in A, FW and DW were observed for inside vs. outside the PetriGAPs. Growth parameters were affected by accession (genotype), explant type, and environment. The type of explant influenced the type of cell growth and subsequent plantlet regeneration capacity. However, overall cell growth showed no abnormalities. The present study demonstrated that jatropha in vitro cell cultures are suitable for growth inside PetriGAPs for a period of 12 weeks. The parameters

  8. Amidated pectin based hydrogels: synthesis, characterization and cytocompatibility study.

    PubMed

    Mishra, R K; Singhal, J P; Datt, M; Banthia, A K

    2007-01-01

    The design and development of pectin-based hydrogels were attempted through the chemical modification of pectin with diethanolamine (DA). Diethanolamine modified pectin (DAMP) was synthesized by the chemical modification of pectin with varying concentrations of DA (1:1,1:2,1:3 and 1:4) at 5 oC in methanol. The modified product was used for the preparation of the hydrogel with glutaraldehyde (GA) reagent. The prepared hydrogels were characterized by Fourier transform infrared (FTIR) spectroscopy; organic elemental analysis, and X-ray diffraction (XRD), and swelling, hemocompatibility and cytocompatibility studies of the prepared hydrogels were also done. FTIR spectroscopy indicated the presence of primary and secondary amide absorption bands. The XRD pattern of the DAMP hydrogel clearly indicated that there was a considerable increase in crystallinity as compared to parent pectin. The degree of amidation (DA) and molar and mass reaction yields (Ym and Yn) was calculated based on the results of organic elemental analysis. Drug release studies from the hydrogel membranes were also evaluated in a Franz's diffusion cell. The hydrogels demonstrated good water holding properties and were found to be compatible with B-16 melanoma cells and human blood.

  9. Preparation, characterization and adsorption behavior of tannin-modified poly(glycidylmethacrylate)-grafted zirconium oxide-densified cellulose for the selective separation of bovine serum albumin.

    PubMed

    Anirudhan, Thayyath Sreenivasan; Rejeena, Sylaja Raveendran; Tharun, Abdul Rauf

    2012-05-01

    Bovine serum albumin (BSA) is one of the major constituents of blood plasma and its recovery is a significantly useful subject for biomedical applications. In this study, a novel adsorbent, tannin-modified poly(glycidylmethacrylate)-grafted zirconium oxide-densified cellulose (TMPGZDC) was synthesized by graft copolymerization reaction of glycidylmethacrylate onto zirconium oxide-densified cellulose (ZDC) in the presence of N,N'-methylenebisacrylamide as cross-linker followed by tannin immobilization. The adsorbent was characterized using TG, XRD, SEM/EDS, FTIR and fluorescence analyses. The efficiency of the TMPGZDC to adsorb BSA from aqueous solutions was studied at different optimized conditions. The optimum pH for maximum adsorption was found to be 4.8 with the adsorption percentage of 97.8% for an initial concentration of 100 mg/L. Equilibrium was achieved within 30 min. The kinetic data were found to follow pseudo-first-order model which is based on solid capacity. The well agreement of equilibrium data with Langmuir isotherm and Redlich-Peterson isotherm models confirms the monolayer coverage of BSA onto TMPGZDC surface and the maximum adsorption capacity at 30°C was found to be 93.11 mg/g. Thermodynamic study revealed an exothermic adsorption process. TMPGZDC was found to be efficient in the selective adsorption of proteins. Spent adsorbent was effectively regenerated [correction of degenerated] with 0.1 M NaCl. The present investigation shows that TMPGZDC is a promising adsorbent for the recovery of BSA from aqueous solutions and protein mixtures.

  10. Crosswell electromagnetic imaging for geothermal reservoir characterization - a feasibility study

    NASA Astrophysics Data System (ADS)

    Samrock, Friedemann; Saar, Martin O.

    2016-04-01

    Most regions in the world do not have ready access to natural convective hydrothermal resources. To use deep geothermal heat as a viable energy resource in low-permeability formations, permeable fracture networks have to be created artificially to enable deep fluid circulation for advective heat transport to a production well. Such generation of enhanced geothermal systems (EGS) is studied in the "Deep Underground Geothermal (DUG)" laboratory at the Grimsel pass, Switzerland. Here, an underground experiment is conducted by hydraulically stimulating a pre-existing shear zone within crystalline rock. The objectives of this project are to better describe and understand the processes acting during reservoir generation. We perform a feasibility study to evaluate the capability of low-frequency crosswell electromagnetic (EM) tomography for mapping of stimulation-induced changes in electrical conductivity. First numerical results show that crosswell EM data are generally sensitive to the inter-well conductivity distribution, which is affected by properties such as interconnected porosity, permeability and the presence of fluids. It thereby provides important information for characterization of potential EGS reservoirs. We present a 3-D forward modeling and inversion study using synthetic data and under realistic conditions, these include the true borehole spacing and the observed electromagnetic noise level in the DUG laboratory. Based on these results we discuss the system requirements and the capability of crosswell EM to recover the inter-well structure and stimulation-induced changes. Besides the numerical study we report on the current status of instrumentation and realization of crosswell EM measurements at the DUG laboratory.

  11. Engineering Studies of a Pilot Plant for Laser Isotope Separation of CARBON-13 by Multiphoton Dissociation of Chlorodifluoromethane

    NASA Astrophysics Data System (ADS)

    Mehmetli, Bulent Ahmet

    Recent research in laser isotope separation by multiphoton dissociation (LISMPD) of ^{13 }C suggests that an LISMPD commercial process is more economical than the cryogenic CO distillation technology currently used to meet most of the world's ^ {13}C demand. In this dissertation, experimental studies of an engineering process for LISMPD of polyatomic molecules is examined. The experimental results have been obtained by MPD of chlorodifluoromethane (CF_2 HCl) to yield ^{13}C -enriched tetrafluoroethylene rm(C_2F _4). Emphasis is on research leading to the development of a practical chemical plant for the preparation of stable isotopes by this method. The experimental program has achieved the design, construction, and operation of a laboratory-scale ^{13}C separation apparatus and parametric dependences of enrichment factors and dissociated fractions. In this experiment, the reactant gas, industrial grade CF_2HCl, flows continuously along the axis of a stainless steel reaction cell. The beam of a commercial CO_2 TEA laser, delivering up to 3 J/pulse at a single wavelength, is focused into the cell to induce isotope-selective multiphoton dissociation. The ^{13}C-enriched reaction product, rm C_2F_4, is analyzed by mass spectroscopy for its isotopic content. Typical production rates of the setup are about 10 g/year ^{13}C at an enrichment of 15% or 1 g/year at an enrichment of 65%. The results of a detailed cost analysis, which takes into account different reaction conditions and laser types, showed that at production rates of 7,000 kg per year, the cost of ^{13}C can be as low as 4/g. This figure is about an order of magnitude less than the cost of ^13 C obtained by cryogenic distillation of CO. The design, construction, and operation of a CO _2 MOPA (Master Oscillator/ Power Amplifier) laser is proposed because a MOPA combines the advantages of favorable isotope separation reaction conditions of TEA lasers and the cheaper photons of cw discharges. Analytical

  12. Separator material for electrochemical cells

    DOEpatents

    Cieslak, W.R.; Storz, L.J.

    1991-03-26

    An electrochemical cell is characterized as utilizing an aramid fiber as a separator material. The aramid fibers are especially suited for lithium/thionyl chloride battery systems. The battery separator made of aramid fibers possesses superior mechanical strength, chemical resistance, and is flame retardant.

  13. Separator material for electrochemical cells

    DOEpatents

    Cieslak, Wendy R.; Storz, Leonard J.

    1991-01-01

    An electrochemical cell characterized as utilizing an aramid fiber as a separator material. The aramid fibers are especially suited for lithium/thionyl chloride battery systems. The battery separator made of aramid fibers possesses superior mechanical strength, chemical resistance, and is flame retardant.

  14. A comparative study of full Navier-Stokes and Reduced Navier-Stokes analyses for separating flows within a diffusing inlet S-duct

    NASA Astrophysics Data System (ADS)

    Anderson, B. H.; Reddy, D. R.; Kapoor, K.

    1993-06-01

    A three-dimensional implicit Full Navier-Stokes (FNS) analysis and a 3D Reduced Navier-Stokes (RNS) initial value space marching solution technique has been applied to a class of separate flow problems within a diffusing S-duct configuration characterized as vortex-liftoff. Both Full Navier-Stokes and Reduced Navier-Stokes solution techniques were able to capture the overall flow physics of vortex lift-off, however more consideration must be given to the development of turbulence models for the prediction of the locations of separation and reattachment. This accounts for some of the discrepancies in the prediction of the relevant inlet distortion descriptors, particularly circumferential distortion. The 3D RNS solution technique adequately described the topological structure of flow separation associated with vortex lift-off.

  15. A computational study of multiple surface-directed phase separation in polymer blends under a temperature gradient

    NASA Astrophysics Data System (ADS)

    Tabatabaieyazdi, Mohammad; Chan, Philip K.; Wu, Jiangning

    2015-10-01

    The surface-directed phase separation (SDPS) phenomena of a model binary polymer blend quenched into the unstable region of its binary symmetric upper critical solution temperature phase diagram is numerically investigated using a mathematical model composed of the nonlinear Cahn-Hilliard (CH) theory for phase separation along with the Flory-Huggins-de Gennes (FHdG) free energy functional. The SDPS occurs in a square domain with a linear temperature gradient along the horizontal direction and with all sides having short range surface potential h 1. The effects of different quench depth, diffusion coefficient, surface potential, and temperature gradient were studied numerically. The numerical results indicate that there is a simultaneous competition between the four surfaces in attracting the preferred polymer. The side with a higher surface potential would win the competition against the side with a lower surface attraction in the case of a uniform quench. The numerical results also indicated a later transition time for higher values of h 1. As surface potential increased, the transition time from complete wetting to partial wetting occurred at a later time on the surface. The impact of different temperature gradient ΔT*/Δx* values on the surface enrichment rate with fixed temperature {{T}1}* at one surface and higher temperature {{T}2}* at the opposite surface was studied for the first time within a multiple surface potential set up. The results showed that higher values of ΔT*/Δx* increased the growth rate of the preferred polymer on the surface adding to the thickness of the wetting layer. The transition time from complete wetting to partial wetting occurred slightly later at the lower temperature side.

  16. Study on selective separation of uranium(VI) by new N,N-dialkyl carboxy-amides

    SciTech Connect

    Suzuki, Shinichi; Sugo, Yumi; Kimura, Takaumi; Yaita, Tsuyoshi

    2007-07-01

    The Feasibility study (FS) on commercialized FR cycle systems has been carried out in Japan. In this Feasibility study, 'Advanced Aqueous' reprocessing was designed as a new reprocessing concept to enhance nuclear non-proliferation by recycling U, Pu and minor actinides (MA) with some fission products (FP). The crystallization and U(VI)/TRU(transuranics) co-extraction technique have been selected as candidate technique in the 'Advanced Aqueous' reprocessing. In JAEA, the result of Feasibility study was received and Fast Reactor Cycle Technology Development Project (FaCT) was started. In the nuclear spent fuel reprocessing, FBR spent fuels will coexist with LWR spent fuels for several decades until FBR cycle begins to operate. For the treatment of LWR spent fuels, high decontamination factor for FP was required for U(VI) storage, and solvent extraction technique was selected in the nuclear fuel treatment. In our laboratory, N,N-di-alkyl carboxy-amides have been developed as extractant based on solvent extraction technique for one of a back-up technology of 'Advanced Aqueous' reprocessing in FBR spent fuel treatments. N,N-di-alkyl carboxy-amides were noted as one of the alternative extractant of tri-butylphosphate (TBP) in the field of nuclear fuel reprocessing. Extraction behavior of U(VI) and Pu(IV) with N,N-di-alkyl carboxy-amides was almost similar to those with TBP. N,N-di-alkyl carboxy-amides have some advantages, namely, their complete incinerability (CHON principle) and high stability for hydrolysis and radiolysis. Their main degradation products are carboxylic acids and secondary amines which hardly affect the separation of U(VI) and Pu(IV) from fission products. Further, the synthesis of N,N-di-alkyl carboxy-amides was relatively easy with reaction of carboxylic chloride and secondary amine. The main purpose of this solvent extraction technique using N,N-di-alkyl carboxy-amides is selective separation of Uranium(VI) with branched N,N-di-alkyl carboxy

  17. Characterization of a Novel Murine Model to Study Zika Virus.

    PubMed

    Rossi, Shannan L; Tesh, Robert B; Azar, Sasha R; Muruato, Antonio E; Hanley, Kathryn A; Auguste, Albert J; Langsjoen, Rose M; Paessler, Slobodan; Vasilakis, Nikos; Weaver, Scott C

    2016-06-01

    The mosquito-borne Zika virus (ZIKV) is responsible for an explosive ongoing outbreak of febrile illness across the Americas. ZIKV was previously thought to cause only a mild, flu-like illness, but during the current outbreak, an association with Guillain-Barré syndrome and microcephaly in neonates has been detected. A previous study showed that ZIKV requires murine adaptation to generate reproducible murine disease. In our study, a low-passage Cambodian isolate caused disease and mortality in mice lacking the interferon (IFN) alpha receptor (A129 mice) in an age-dependent manner, but not in similarly aged immunocompetent mice. In A129 mice, viremia peaked at ∼10(7) plaque-forming units/mL by day 2 postinfection (PI) and reached high titers in the spleen by day 1. ZIKV was detected in the brain on day 3 PI and caused signs of neurologic disease, including tremors, by day 6. Robust replication was also noted in the testis. In this model, all mice infected at the youngest age (3 weeks) succumbed to illness by day 7 PI. Older mice (11 weeks) showed signs of illness, viremia, and weight loss but recovered starting on day 8. In addition, AG129 mice, which lack both type I and II IFN responses, supported similar infection kinetics to A129 mice, but with exaggerated disease signs. This characterization of an Asian lineage ZIKV strain in a murine model, and one of the few studies reporting a model of Zika disease and demonstrating age-dependent morbidity and mortality, could provide a platform for testing the efficacy of antivirals and vaccines.

  18. Characterization of a Novel Murine Model to Study Zika Virus

    PubMed Central

    Rossi, Shannan L.; Tesh, Robert B.; Azar, Sasha R.; Muruato, Antonio E.; Hanley, Kathryn A.; Auguste, Albert J.; Langsjoen, Rose M.; Paessler, Slobodan; Vasilakis, Nikos; Weaver, Scott C.

    2016-01-01

    The mosquito-borne Zika virus (ZIKV) is responsible for an explosive ongoing outbreak of febrile illness across the Americas. ZIKV was previously thought to cause only a mild, flu-like illness, but during the current outbreak, an association with Guillain–Barré syndrome and microcephaly in neonates has been detected. A previous study showed that ZIKV requires murine adaptation to generate reproducible murine disease. In our study, a low-passage Cambodian isolate caused disease and mortality in mice lacking the interferon (IFN) alpha receptor (A129 mice) in an age-dependent manner, but not in similarly aged immunocompetent mice. In A129 mice, viremia peaked at ∼107 plaque-forming units/mL by day 2 postinfection (PI) and reached high titers in the spleen by day 1. ZIKV was detected in the brain on day 3 PI and caused signs of neurologic disease, including tremors, by day 6. Robust replication was also noted in the testis. In this model, all mice infected at the youngest age (3 weeks) succumbed to illness by day 7 PI. Older mice (11 weeks) showed signs of illness, viremia, and weight loss but recovered starting on day 8. In addition, AG129 mice, which lack both type I and II IFN responses, supported similar infection kinetics to A129 mice, but with exaggerated disease signs. This characterization of an Asian lineage ZIKV strain in a murine model, and one of the few studies reporting a model of Zika disease and demonstrating age-dependent morbidity and mortality, could provide a platform for testing the efficacy of antivirals and vaccines. PMID:27022155

  19. Gas separating

    DOEpatents

    Gollan, A.

    1988-03-29

    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. 3 figs.

  20. Gas separating

    DOEpatents

    Gollan, A.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. 3 figs.